description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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BACKGROUND OF THE INVENTION
This invention relates to an apparatus for cleaning teeth while in the shower. More particularly, this invention relates to an apparatus which may be attached to a shower between the shower inlet pipe and shower head and which will deliver a jet stream of water into the mouth concomitant with showering.
Various methods and apparatus have been and are being used for cleaning the teeth and oral cavity. The most generally used apparatus is the conventional toothbrush containing a dentifrice in the from of a paste or gel. Of recent years apparatus have also been developed for applying a jet of water against the teeth. This method is often preferably to the use of a brush when cleaning teeth containing orthodontic appliances. A jet stream of water is often able to penetrate crevices and spaces between teeth and orthodontic appliances which cannot be reached by a brush thereby dislodging food particles and plaque which would otherwise not be removed. A problem associated with the use of either a tooth brush or a water jet dispenser is that a mirror, basin, walls and other areas adjacent thereto often become covered with water, toothpaste or particles that splatter from the open mouth during the cleaning process. As a result dentists see many people, teenagers with orthodontic appliances in particular, who avoid cleaning their teeth properly because it is a time consuming and messy procedure. Moreover, many water jet type of appliances fall into disuse because of the water splash problem and the necessity to clean up each time the appliance is used.
OBJECTS AND BRIEF DESCRIPTION OF THE INVENTION
It is therefore an object of the present invention to provide an apparatus for efficiently cleaning the teeth and oral cavity in general by a jet stream of water while taking a shower, thereby eliminating problems of water splashing and clean-up.
It is also an object of the present invention to provide an apparatus for cleaning teeth by a jet stream of water in a shower wherein the water flow and pressure through the apparatus and into the mouth may be regulated by means of a needle valve.
Another object of the invention is to provide an apparatus for cleaning teeth in a shower by a jet stream of water wherein the applicator nozzle may contain a dentifrice, fluoride, breath freshener, mouthwash, medicament or other material which may become mixed with the water passing through the applicator and applied to the mouth in the jet stream.
These and other objects may be accomplished by means of an apparatus in the form of a valve positioned intermediate the shower head and shower inlet pipe. The valve is threaded so as to thread onto the inlet pipe and into the shower head thereby becoming easily attachable to any conventional shower. The valve consists of a hollow body forming a water passageway from the inlet pipe to the shower head. An orifice is contained in the lateral side of the valve body at the bottom. A nipple or lip, which is integral with the valve body, surrounds the orifice on the outside of the valve and protrudes downwardly forming a hose connection. On the inside of the valve and surrounding the orifice is a circular or conoidal seat. In the valve body wall exactly opposite the orifice and in alignment therewith is a threaded aperture through which is threaded a valve needle having a circular pointed or conoidal end which seats into the area surrounding the orifice when the needle is threaded across the water passageway thereby sealing the orifice. The opposite end of the valve needle outside the valve body containsan enlarged end or knob which aids in turning the needle with the fingers.
A hose is connected at one end to the protruding nipple and at the other to an applicator having a spray nozzle. The applicator has an enlarged barrel like reservoir portion adjacent the hose connection adapted to hold a chemical composition such as a dentifrice, mouthwash, breath freshener, fluoride preparation and the like. The spray or jet nozzle is located at the end of the barrel portion opposite the hose connection.
The apparatus is operated in the shower by first turning on the shower to the desired temperature and then opening the valve needle a sufficient distance to provide for the correct amount of water and pressure leaving through the orifice and passing, via the hose through the applicator nozzle and into the mouth of the user.
DRAWINGS
FIG. 1 is a fragmentary perspective view of a shower having the apparatus of the present invention attached thereto.
FIG. 2 is a longitudinal cross section of the valve illustrated in FIG. 1 showing the operational function of the needle valve.
FIG. 3 is a front end view of the valve illustrated in FIG. 1.
FIG. 4 is a top view of the valve illustrated in FIG. 1.
FIG. 5 is a longitudinal cross section of one embodiment of an oral hygiene applicator suitable for use in the present invention.
DETAILED DESCRIPTION OF THE INVENTION
There is shown in FIGS. 1-5 a complete embodiment of the invention.
FIG. 1 shows in perspective the apparatus completely assembled in a shower and ready for use. The apparatus as shown in FIGS. 1 and 2 consists of an open hollow valve body 10 internally threaded at one end 11 for attachment to a shower inlet pipe 12 and outwardly threaded at the opposite end 13 for attachment of a shower head 14 thereon. The lateral sidewalls may be of uniform thickness or may be thicker in the central section intermediate ends 11 and 13 as shown in FIG. 2. An orifice 15 extends through one lateral sidewall and is of lesser diameter than the diameter of the main longitudinal passageway. A nipple 16, which is integral with the lateral sidewall, surrounds the orifice on the outside of the valve body 10 and forms an extension thereof. The nipple serves as a hose connection as will be more completely described hereinafter. The area immediately surrounding the orifice at the inside of the lateral sidewall is beveled to form a circular or conoidal seat 17. In the lateral sidewall opposite the orifice 15 and in alignment therewith a threaded aperture into which is inserted a threaded valve needle 18. The inner end 19 of the valve needle 18 is pointed to conoidal and dimensioned to engage firmly into seat 17 and seal orifice 15. The outer end of valve needle 18 contains a knob 20 to facilitate the threading of the valve needle across the hollow valve body. The valve needle 18 may be configured to be surrounded by an O ring or other sealing means. With the valve needle 18 firmly seated into valve seat 17 the orifice is sealed; however, by turning the knob 20 the valve nose 19 will be retracted from the valve seat 17 allowing water to be diverted from the hollow valve body and through the orifice 15.
As also shown in FIG. 2 the longitudinal passageway through valve body 10 is preferably stepped i.e., from a 1/2" ID to a 3/8"ID, thereby forming a step or seat 21 for seating a ring gasket 22 which seals the valve body 10 to the inlet pipe 12 when engaged thereon.
While not essential to the operation of the present invention, the valve body also preferably contains attaching means 23 as an integral part of the valve body for securing the oral hygiene applicator 24 thereto when not in use as will be more fully described.
A hose 25 is stretch fitted over nipple 16 and may be further secured by means of clamps if desired. The hose 25 is of sufficient length to be freely moved about in the shower by the user for the intended purpose. At the opposite end of hose 25 is the applicator 24. While any suitable applicator may be used the one illustrated in FIG. 5 is particularly useful. This applicator consists of two detachable pieces 26 and 27 which, when connected, form a lower barrel shaped cylindrical reservoir portion 28 and an upper nozzle portion 29. The two pieces interconnect along the barrel portion by means, e.g., interlocking threads, such that access is provided into the reservoir 28 for the addition of a dentifrice, mouthwash, breath freshener, fluoride preparation or other water soluble or dispersible composition thereto. The lowermost portion of applicator 24 consists of a hollow nipple 30 which serves as a hose connection and provides access for incoming water into the reservoir 28. The reservoir is of greater diameter than the nozzle and also serves as a handle for the applicator. The nozzle 29 is generally cylindrical and is located at the opposite end of the reservoir from the nipple 30. The nozzle tapers to a smaller diameter as it extends away from the reservoir and terminates in an orifice of a size predetermined to emit therefrom an appropriate jet stream of water. The tip 31 of the nozzle is preferably curved so as to terminate in a plane some 30 to 90 degrees from the longitudinal axis of the barrel and nozzle thereby making it easier for the user to direct the water jet into the desired position in the mouth.
The mouth 32 of the nozzle, preferably extends a small distance into the reservoir. This encourages mixing of chemical compositions within the reservoir by creating turbulence therein. Thus, materials placed in the reservoir, such as dentifrices, will be dissolved or suspended and enter the nozzle mouth from within the interior of the reservoir rather than being forced out the extreme end of the reservoir chamber, where larger undissolved or unsuspended particles may accumulate.
Various materials may be placed within the reservoir simply by disconnecting parts 26 and 27 and adding the desired amount of substance to the open reservoir chamber. Dentifrices, mouthwashes, breath fresheners, antiseptics, disinfectants, fluoride preparations or any other types of oral preparations, which are either water soluble or suspendible may be added to the reservoir.
The holder 23 on the valve body is preferably shaped to have two extending arms forming a semicircle in between adapted to functionally engage and hold the barrel like reservoir portion of the applicator 24 as illustrated in FIG. 1. The holder 23 may be positioned such that the applicator may be either vertical or horizontal when engaged.
The apparatus is preferably assembled so that the orifice 15 in the valve body 10 is pointed downward with the needle valve knob 20 forming the uppermost top of the assembly. In other words the needle valve is in a vertical position. However, other positions, such as the needle valve being horizontal may also be used, and any terminology, such as top or bottom, when referring to position is deemed to include all operable positions.
The apparatus is intended to be used only when the user is showering and thus no attempt is made to prevent water from passing through the shower head when using the oral hygiene applicator. The apparatus is preferably stored with the valve needle engaged in the valve seat sealing orifice 15. When using the apparatus, the shower is first adjusted to the proper temperature any desired dentifrice or other substance has been added to the applicator, the valve needle is rotated by the user to emit the proper amount of water through applicator nozzle 29 and out through tip 31 in the form of a jet spray. The jet of water is directed into the mouth and against the teeth thereby dislodging food particles, plaque and other foreign materials. This method is particularly beneficial in cleaning teeth containing braces or other forms of orthodontic appliances. There is no need to worry over water splashing and therefore a more thorough and rigorous cleaning process may be carried out than is possible at a bathroom basin or sink.
Although the invention as has been described is deemed to be that which would form the preferred embodiment thereof, it is recognized that departures may be made therefrom and still be within the scope of the invention which is not to be limited to the details disclosed but is to be accorded the full scope of the claims and any and all equivalent devices and apparatus. | An oral hygiene apparatus for attachment to a shower head assembly for cleansing the teeth and the oral cavity with a jet stream of water while showering. The apparatus housing is in the form of a hollow valve body which interconnects the shower inlet pipe with the shower head. A hose leading from a needle valve regulated orifice in the valve body connects to a nozzle applicator. The needle valve controls the flow of water into the orifice, through the hose and out the nozzle. The nozzle applicator contains a reservoir for holding a dentifrice, fluoride preparation, breath freshener and the like. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to an exhaust timing control device for a two-cycle engine and more particularly to an improved arrangement for controlling the flow of exhaust gases from the combustion chamber of an internal combustion engine so as to achieve good performance under all running conditions.
Like many factors in engine design, the timing of exhaust port opening is generally a compromise between good performance at low speeds and good performance at high speeds. Recently, however, it has been determined that the performance of an engine can be increased at the maximum end without sacrificing low speed running if a control valve is utilized in conjunction with the exhaust port so as to delay opening of the exhaust port at low speeds and to cause it to open earlier at high speeds. Such exhaust port controls are frequently employed in conjunction with two-cycle internal combustion engines wherein a main control valve varies the timing of opening of the exhaust port.
In order to further increase the performance of engines, frequently multiple exhaust ports are employed. Where an auxiliary exhaust port is provided, it is also desirable to vary its opening and closing in response to engine running conditions so as to improve performance. In conjunction with two-cycle internal combustion engines and other engines, it is not always possible to put the control for the auxiliary exhaust port directly at the exhaust port. For this reason, prior art type of auxiliary port controls have been on/off type of devices.
In conjunction with the running of prior art engines having both main and auxiliary exhaust ports and controls for each of them with the auxiliary port control being an on/off type of control. It has been found that there is a dip or valley in the torque and power curve that occurs at the time when the auxiliary port control is moved from its closed to its opened position. This can be seen in the curve D in FIG. 1. This is a power to speed curve and it will be seen that at the time when the auxiliary port control opens at approximately 8,000 rpm, there is a dip in the power curve which will coincide with a dip in the torque curve.
It is, therefore, a principal object of this invention to provide an improved exhaust timing control system for engines that will increase the performance at high ends without sacrificing performance under any other running condition.
It is a further object of this invention to provide an improved port control arrangement for engines that will increase maximum performance without any dip in the torque curve or power curve.
It is a further object of this invention to provide an improved port controlling arrangement for two-cycle internal combustion engines.
SUMMARY OF THE INVENTION
This invention is adapted to be embodied in an exhaust port system for an internal combustion engine that is comprised of a main exhaust port for discharging combustion products from the engine and an auxiliary exhaust port for discharging combustion products from the engine. Means are provided for sequentially opening and closing of the exhaust ports during a complete cycle of engine operation. Auxiliary exhaust port control means are provided for selectively opening and closing an auxiliary exhaust passage communicating with the auxiliary exhaust port in response to an engine condition for selectively precluding combustion products from flowing the auxiliary exhaust port even when the auxiliary exhaust port is opened. Means are provided for retarding the effective time of opening of the main exhaust port upon operation of the auxiliary exhaust port control means for providing a smoother power curve.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graphical view showing engine speed in relation to power with the curve D representing the prior art type of construction in the curve C representing the power curve of an engine constructed in accordance with an embodiment of the invention.
FIG. 2 is a cross-sectional view taken through a single cylinder of an internal combustion constructed in accordance with an embodiment of the invention.
FIG. 3 is an enlarged cross-sectional view taken generally along the line 3--3 of FIG. 2.
FIG. 4 is a developed view showing the porting arrangement for the engine.
FIG. 5 is a schematic view showing the complete engine and its controls in schematic fashion.
FIG. 6 is a graphical view showing the exhaust port timing of the main and auxiliary exhaust ports in accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now in detail to the drawings and initially primarily to FIGS. 2 and 3, an internal combustion engine constructed in accordance with an embodiment of the invention is identified generally by the reference numeral 11. Only a single cylinder engine is depicted because it is believed that those skilled in the art can readily understand how the invention can be practiced in conjunction with multiple cylinder engines. Also, although a reciprocating engine is shown, it is to be understood that certain facets of the invention may be employed in conjunction with other types of engines. The engine 11 is, in the illustrated and preferred embodiment, of the two-cycle crank case compression type. Certain facets of the invention, however, may also be applied to engines operating on other principals such as four strokes cycle engines.
The engine 11 is comprised of a cylinder block 12 having a cylinder bore 13 in which a piston 14 reciprocates. The piston 14 is connected to a connecting rod 15 for driving crankshaft 16 that is rotatably journaled in a crankcase chamber defined by the cylinder block 12 and a crankcase member 17.
A cylinder head 18 is affixed to the cylinder block 12 in a known manner and supports a spark plug 19 which is fired by a capacitor discharge ignition system indicated generally at 21 in FIG. 5.
A fuel air charge is delivered to the crankcase chamber in which the crankshaft 16 rotates from a suitable charge-forming device such as a carburetor 22. The carburetor 22 communicates with the crankcase chamber via a reed type check valve 23 so as to prevent reserve flow.
The charge which is compressed in the crankcase chamber during the descent of the piston 14 is transferred to the area above the piston through a plurality of scavenged passages 24 that extend from the crankcase chamber and which terminate in scavenge ports 25 spaced around the periphery of the cylinder bore 13 in a pattern as shown in FIG. 4.
The burnt charge is exhausted from the combustion chamber through a main exhaust port 26 and a pair of auxiliary exhaust ports 27 having a configuration and layout as also shown best in FIG. 4. It should be noted that the main exhaust port 26 is considerably larger than the auxiliary exhaust ports 27 and will open at an earlier time during the piston travel on its exhaust stroke and close at a later time than the auxiliary ports 27. The configuration illustrated has been found to provide maximum power under high output conditions. However, as is well known, the exhaust porting that provides maximum power will provide poor running at low speeds. For this reason, there is provided a control valve arrangement that will now be described.
As may be best seen in FIG. 3, the main exhaust port 26 communicates with a main exhaust passageway 28 which, in turn, communicates with an exhaust pipe 29 for discharging the exhaust gases to the atmosphere after having passed through a silencer (not shown). The auxiliary exhaust ports 27 each communicate with respective auxiliary exhaust passages 31 which merge in their downstream ends with the main exhaust passage 28.
A main control valve 32 is slidably supported in the cylinder head and cylinder block and has a valving portion that is adapted to obstruct a portion of the exhaust port 26 as best shown in FIG. 4. As the main control valve 32 is lowered from the fully opened position to the position shown in FIG. 4 the timing at which the main exhaust port 26 effectively opens will be retarded. By retarding the opening of the main exhaust port 26 at low and mid-range speeds the running of the engine will be improved since the high overlaps that provide maximum power also provide poor running at low speeds. The main control valve 32 is connected by means of a Boden wire cable 33 to an appropriate actuator, shown schematically at 34 in FIG. 5. The actuator 34 may be of any known type of servo device for effecting the movement of the main control valve 32.
As may be seen clearly from FIG. 3, there are provided a pair of auxiliary control valves 35 in the auxiliary exhaust passages 31. Because of the configuration of the exhaust port and cylinder block it is not practical to put the auxiliary control valves 35 in direct registry with the auxiliary exhaust ports 27. For this reason, the auxiliary control valves 35 are on/off valves in that they are either fully opened or fully closed.
A Boden wire cable 36 connects the auxiliary control valves 35 to a remote actuator shown schematically at 37 in FIG. 5. The auxiliary control actuator 37 may be of any known type of servo device.
Referring now to FIG. 5, the control mechanism for the main control valve 32 and auxiliary control 35 will be described. It will be noted that the engine 11 is provided with a magneto generator, indicated generally by the reference numeral 38, which outputs a charging current to a voltage regulator 39 which, in turn, charges a battery 41. In addition, the magneto generator 38 includes a trigger coil that outputs a trigger pulse a to the capacitor discharge ignition system 21 for initiating firing of the spark plug 19 through an ignition coil 42. As is well known in this art, the ignition coil 42 discharges when with a voltage signal c from a capacitor which has been charged from a generating coil of the magneto generator 38, which charging coil output is designated at b.
Because of the output of the pulser coil a or the generating coil b, the capacitor discharge ignition circuit 21 can also output a signal d that is indicative of the speed at which the engine 11 is operated. This engine speed signal is transferred to a computer circuit shown schematically at 43 that is programmed with the control for the main exhaust control valve 32 and the auxiliary exhaust control valves 35. These control signals include a timing varying signal e that is transmitted to the servo motor 34 for the main control valve 32 and either an opening control signal f 1 or a closing control signal f 2 to the servo motor 37 for the auxiliary control valves 35.
Although a wide variety of sequensive operations may be employed in conjunction with the invention, a particular sequence is shown in FIG. 6 which is fairly typical of the way the invention may be practiced. As will be noted from the curve A, the auxiliary control valves 35 are normally maintained in a closed position until the engine reaches a predetermined speed, 8,000 rpm in the illustrated embodiment, at which time the valves 35 are fully opened. On the other hand, the main control valve 32 is normally held in its lower most position H 1 which provides the maximum retard of the opening of the main exhaust port 26 at low and mid-range speeds. At some speed, 5,000 rpm in the illustrated embodiment, the main control valve 32 is opened with a ramp like function until the valve is fully opened at some pre-determined higher range speed.
However, in accordance with the invention and to avoid the torque or power dip as shown by the curve D in FIG. 1, at about the time the auxiliary control valves 35 are moved to their opened position, the degree of opening of the main control valve 32 is retarded or moved back toward its fully retarded position as shown by the line B-1 B-2. This modifying signal to the servo motors 34 is shown at e' wherein the control signal is delayed or retarded from what would be the normal condition at the speed at Which the auxiliary control valves 35 are open. As a result, it has been found that the torque curve and power curve will be smooth as shown by the curve C in FIG. 1. The control main control valve 32 then is continued open as on a ramp function as before until it is fully opened at, for example, 9,000 rpm in the illustrated example.
In the illustrated embodiment, the engine 11 is watercooled and for this reason the cylinder block 12 is provided with a cooling jacket 44. The remainder of the cooling system for the engine 11 can be considered to be conventional and since it forms no part of the invention, further description or illustration of it is not believed to be required to enable those skilled in the art to make and use the invention.
It should be apparent from the foregoing description that the described valving arrangement for the exhaust ports permits the attainment of very high power outputs without any sacrifice in low and mid-range performance. Although an embodiment of the invention has been illustrated and described, various changes and modifications may be made without departing from the spirit and scope of the invention, as defined by the appended claims. | An exhaust port controlling arrangement for an internal combustion engine having both main and auxiliary exhaust ports. A main control valve cooperates with the main exhaust port for varying the timing at which the exhaust port opens in response to engine speed. An on/off auxiliary control valve is positioned in a passage leading from the auxiliary exhaust port for opening and closing the flow through the auxiliary exhaust passage in response to an engine condition. Means retard the opening of the main exhaust port upon opening of the auxiliary exhaust ports to improve the power and torque curves of the engine. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of Invention
[0002] The present invention generally relates to semiconductor devices equipped with a test mode and a method for operating the same. More particularly, the present invention relates to a semiconductor device with a built-in measurement circuit that supports examinations of the semiconductor device when the semiconductor device is examined by a test apparatus such as an IC tester in a test mode.
[0003] 2. Description of Related Art
[0004] [0004]FIG. 3 shows a conventional semiconductor device. In the semiconductor device shown in FIG. 3, buffer circuits 101 , 102 , 103 , . . . , each having two inverters, are inserted as input circuits between input terminals 1 , 2 , 3 , . . . and an internal circuit 30 .
[0005] As shown in FIG. 3, when input data is applied to the input terminals 1 , 2 , 3 , . . . from a test apparatus such as an IC tester, the input data is supplied to the internal circuit 30 through the buffer circuits 101 , 102 , 103 , . . . , respectively. Therefore, when this type of semiconductor device is examined by using the test apparatus, logic levels to be inputted in the internal circuit need to be measured. For this purpose, it is proposed to provide a measurement circuit that operates in a test mode within the semiconductor device, to thereby measure logic levels that are inputted in the internal circuit. In the semiconductor device shown in FIG. 3, for example, AND circuits 21 , 22 , 23 , . . . , each including a NAND gate and an inverter, are provided as measurement circuits.
[0006] The AND circuits are connected to a series of the data input terminals in a chain like manner. More particularly, for example, input data from the second data input terminal 2 is supplied through the buffer circuit 102 to one of two inputs of the second AND circuit 22 . Also, an output from the AND circuit 21 that is connected to the second AND circuit 22 in an immediately proceeding stage is supplied to the other input of the AND circuit 22 . Furthermore, an output of the AND circuit 22 is supplied to one input of the AND circuit 23 , and input data from the third data input terminal 3 is inputted to the other input of the AND circuit 23 . In this manner, the multiple AND circuits are connected in a chain-like manner.
[0007] A test mode signal TEST is supplied through a test mode signal input terminal 60 to one input of the AND circuit 21 in the first stage. The test mode signal TEST is at high level in a test mode. Also, an output of one of the AND circuits in the last stage is supplied to one input of a selection circuit 70 . An output of the internal circuit 30 is supplied to the other input of the selection circuit 70 . The selection circuit 70 is controlled by the test mode signal TEST. The selection circuit 70 selects the output of the internal circuit 30 in a normal operation mode, and selects the output of the AND circuit in the last stage in a test mode. An output of the selection circuit 70 is read out through an output terminal 80 by an external device.
[0008] It is noted that, in the normal operation mode, the test mode signal TEST is at low level. Therefore, outputs from the AND circuits 21 , 22 , 23 , . . . are at low level without regard to the level of the input data. On the other hand, the test mode signal TEST is at high level in the test mode. Therefore, when input data on input systems other than an input system that is subject to measurement are fixed at high level, and the logic level of input data (for example, input data applied to the data input terminal 1 ) in the input system that is subject to measurement is changed, the logic level inputted in the input system of the internal circuit 30 is accordingly changed. The change is transferred through the AND circuits 21 , 22 , 23 , . . . that are connected in a chain-like manner, and outputted through the selection circuit 70 and then through the output terminal 80 . In this manner, the logic level of an input within the internal circuit 30 can be measured without regard to differences in the specification of the input circuits of the semiconductor device.
SUMMARY OF THE INVENTION
[0009] When the buffer circuits are used as input circuits in a manner shown in FIG. 3, a problem occurs when a power supply to a separate system that supplies input data is tuned off. In other words, in such an instance, the data input terminals of the semiconductor device are placed in a high-impedance state, an input to the buffer circuits may have a potential close to an intermediate potential between a power supply potential V DD and a power supply voltage V SS , i.e., a value of (V DD +V SS )/2. Alternatively, an input to the buffer circuits may have a potential close to a value of V DD /2 when a power supply voltage V SS is at a grounding potential. As a result, a drain current may constantly flow through the inverters that form the buffer circuits.
[0010] In order to prevent wasteful current from flowing even in the instance described above, some techniques are proposed. For example, an AND circuit 11 shown in FIG. 4 or an OR circuit 91 shown in FIG. 5 is used to form an input circuit instead of the buffer circuit 101 used in the semiconductor device shown in FIG. 3.
[0011] Referring to FIG. 4, the AND circuit 11 includes a NAND gate and an inverter. One of input terminals of the NAND gate is connected to the data input terminal 1 . The other input terminal of the NAND gate is supplied with a control signal C that is internally generated in the semiconductor device. Even when the data input terminal 1 is placed in a high-impedance state, an output of the NAND gate of the AND circuit 11 is always at high level if the control signal C is maintained at low level. Therefore, wasteful current does not flow.
[0012] Referring to FIG. 5, the OR circuit 91 includes a NOR gate and an inverter. One of input terminals of the NOR gate is connected to the data input terminal 1 . The other input terminal of the NOR gate is supplied with a control signal C bar that is internally generated in the semiconductor device. Even when the data input terminal 1 is placed in a high-impedance state, an output of the NOR gate of the OR circuit 91 is always at low level if the control signal C bar is maintained at high level. Therefore, wasteful current does not flow.
[0013] However, when the semiconductor device having an input circuit that is formed with the AND circuit 11 shown in FIG. 4 is tested, the output of the AND circuit 11 is fixed at low level and does not change even when the logic level on the data input terminal 1 is changed, unless the control signal C is changed to high level. Also, when the semiconductor device having an input circuit that is formed with the OR circuit 91 shown in FIG. 5 is tested, the output of the OR circuit 91 is fixed at high level and does not change even when the logic level on the data input terminal 1 is changed, unless the control signal C bar is changed to low level.
[0014] Accordingly, when the AND circuit 11 shown in FIG. 4 or the OR circuit 91 shown in FIG. 5 is inserted in an input system of the semiconductor device having a measurement circuit that uses the AND circuits 21 , 22 , 23 , . . . shown in FIG. 3, the logic level of an input in the input circuit cannot be measured unless the internal control signal is changed.
[0015] In view of the above, it would be desired to provide a semiconductor device having an input circuit and a method for operating the same, in which the logic level of an input on the input circuit can be measured by a test apparatus such as an IC tester even when a gate circuit that uses an internally generated control signal is used in a first stage of the input circuit.
[0016] A semiconductor device in accordance with one exemplary embodiment of the present invention has an internal circuit in which input data is gated and supplied to the internal circuit according to an internal control signal generated within the semiconductor device. The semiconductor device has N number (N being two or greater integers) of data input terminals for inputting input data, and a test mode input terminal for inputting a test mode signal. An OR device is provided for obtaining a logical sum of the internal control signal and the test mode signal. The semiconductor device also has N number of gate circuits that are supplied with the input data applied to the N data input terminals, respectively. When an output of the OR device is active, those of the N gate circuits responsive to the output of the OR device pass the input data applied to the data input terminals. The internal circuit is supplied with outputs of the N gate circuits. The semiconductor device has a first stage AND device and second through Nth stage AND devices. The first stage AND device has a first input that is supplied with an output of a first one of the N gate circuits and a second input that is supplied with the test mode signal. The second through Nth stage AND devices respectively have first input terminals that are supplied with outputs of second through Nth ones of the N gate circuits, respectively, and second input terminals that are supplied with outputs of the first through (N-1)th stage AND devices, respectively.
[0017] The semiconductor device may further include a selection circuit that selects an output of the internal circuit in a normal operation mode and selects an output of the Nth stage AND device in a test mode, and an output terminal that is supplied with an output of the selection circuit.
[0018] In the semiconductor device, the internal control signal and an output of the OR device may be active at high level. Alternatively, the internal control signal and an output of the OR device may be active at low level.
[0019] By a semiconductor device having the structure described above in accordance with the embodiment of the present invention, even when a gate circuit that uses an internally generated control signal is used in one of the input circuits in the first stage thereof, the operation of the gate circuit can be controlled by using a test mode signal. Therefore, the logic level of an input in the input circuits can be measured by using a test apparatus such as an IC tester.
[0020] Other features and advantages of the invention will be apparent from the following detailed description, taken in conjunction with the accompanying drawings that illustrate, by way of example, various features of embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] [0021]FIG. 1 schematically shows a structure of a semiconductor device in accordance with a first exemplary embodiment of the present invention.
[0022] [0022]FIG. 2 schematically shows a structure of a semiconductor device in accordance with a second exemplary embodiment of the present invention.
[0023] [0023]FIG. 3 schematically shows a structure of a semiconductor device including buffer circuits in an input system.
[0024] [0024]FIG. 4 shows an example of a gate circuit that is inserted in the input system of the semiconductor device.
[0025] [0025]FIG. 5 shows another example of a gate circuit that is inserted in the input system of the semiconductor device.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] Preferred exemplary embodiments of the present invention will be described below with reference to the accompanying drawings.
[0027] [0027]FIG. 1 shows a structure of a semiconductor device in accordance with a first exemplary embodiment of the present invention. Referring to FIG. 1, the semiconductor device has a plurality of data input terminals 1 , 2 , 3 , . . . , N. It is noted that FIG. 1 shows only three data input terminals, and fourth through Nth data input terminals are omitted to simplify the illustration. Input data are inputted to the respective data input terminals 1 , 2 , 3 , . . . , N from an external test apparatus. Also, the semiconductor device also has a test mode signal input terminal 60 . A test mode signal TEST that is at high level in a test mode is supplied to the test mode signal input terminal 60 from the external test apparatus.
[0028] The semiconductor device of the present embodiment includes AND circuits 11 , 12 , 13 , . . . N as gate circuits that gate the input data. The input data applied to the data input terminals 1 , 2 , 3 , . . . , N are supplied to an internal circuit 30 of the semiconductor device through the AND circuits 11 , 12 , 13 , . . . N that provide logical multiplication of the input data and an internal control signal C. It is noted that FIG. 1 shows only three AND circuits 11 , 12 , 13 as gate circuits, and fourth through Nth AND circuits are omitted to simplify the illustration. Each of the AND circuits 11 , 12 , 13 , . . . N include a NAND gate and an inverter. Input data is supplied to one of two inputs of each of the NAND gates from the corresponding one of the data input terminals, and an output from an OR circuit 50 is inputted in the other input of each of the NAND gates. The OR circuit 50 includes a NOR gate and an inverter. The internal control signal C that is internally generated in the internal circuit 30 is inputted in one of two inputs of the NOR gate of the OR circuit 50 and the test mode signal TEST is inputted to the other input of the NOR gate of the OR circuit 50 . The OR circuit 50 provides a logical sum of the internal control signal C and the test mode signal TEST.
[0029] Even when the internal control signal C is normally at low level in the test mode, the test mode signal TEST is at high level. As a result, the output of the OR circuit 50 is at high level. Therefore, when the logic levels of the data input terminals 1 , 2 , 3 , . . . , N are changed, outputs of the AND circuits 11 , 12 , 13 , . . . N are accordingly changed.
[0030] Furthermore, the semiconductor device includes AND circuits 21 , 22 , 23 , . . . , N as measurement circuits within the semiconductor device.
[0031] Each of the AND circuits 21 , 22 , 23 , . . . N includes a NAND gate and an inverter It is noted that FIG. 1 shows only three AND circuits 21 , 22 , 23 as measurement circuits within the semiconductor, and fourth through Nth AND circuits are omitted to simplify the illustration.
[0032] A first one ( 21 ) of the AND circuits as measurement circuits has a first input that is supplied with an output of a first one ( 11 ) of the AND circuits as gate circuits and a second input that is supplied with the test mode signal. Second one ( 22 ) through Nth AND circuits as measurement circuits have first inputs that are supplied with outputs of the second ( 12 ) through Nth ones of the AND circuits as gate circuits, respectively, and second inputs that are supplied with outputs of immediately preceding ones of the AND circuits as measurement circuits (i.e., the AND circuit 21 through (N-1)th AND circuit), respectively.
[0033] In one embodiment, for example, input data from the second data input terminal 2 is supplied through the AND circuit 12 (i.e., second gate circuit) to one of two inputs of the second stage AND circuit 22 . Also, an output from the AND circuit 21 in an immediately proceeding stage is supplied to the other input of the AND circuit 22 . Furthermore, an output of the AND circuit 22 is supplied to one of two inputs of the AND circuit 23 in the next stage, and input data from the third data input terminal 3 is inputted to the other input of the AND circuit 23 . In this manner, the multiple AND circuits are connected to one another in a chain-like manner.
[0034] The test mode signal TEST is supplied to one of two inputs of the AND circuit 21 in the first stage. Also, an output of the AND circuit in the measurement circuits in the last stage (i.e., the Nth stage AND circuit) is supplied to one of two inputs of a selection circuit 70 . An output of the internal circuit 30 is inputted to the other input of the selection circuit 70 . The selection circuit 70 is controlled by the test mode signal TEST. The selection circuit 70 selects the output of the internal circuit 30 in a normal operation mode, and selects the output of the AND circuit in the last stage in a test mode. An output of the selection circuit 70 is read out through an output terminal 80 by an external device.
[0035] It is noted that, in the normal operation mode, the test mode signal TEST is at low level. Therefore, outputs from the AND circuits 21 , 22 , 23 , . . . , N are at low level without regard to the level of the input data. On the other hand, the test mode signal TEST at high level is provided in the test mode. Therefore, when input data on the input systems other than the input system that is subject to measurement is fixed at high level, and the logic level of input data on the input system that is subject to measurement is changed, the change is transferred through the AND circuits 21 , 22 , 23 , . . . , N that are connected in a chain-like manner and through the selection circuit 70 , and outputted from the output terminal 80 . In this manner, inputted logic levels on the AND circuits 11 , 12 , 13 , . . . , N can be measured without regard to variations in the specification of the input circuits of the semiconductor device.
[0036] Next, a second exemplary embodiment of the present invention is described below with reference to FIG. 2. The second embodiment is different from the first embodiment in that OR circuits are used instead of the AND gates as gate circuits.
[0037] The semiconductor device of the second embodiment includes OR circuits 91 , 92 , 93 , . . . N as gate circuits that gate the input data. The input data applied to the data input terminals 1 , 2 , 3 , . . . , N are supplied to an internal circuit 30 of the semiconductor device through the OR circuits 91 , 92 , 93 , . . . N that provide logical sums of the input data and an internal control signal C bar. It is noted that FIG. 2 shows only three OR circuits 91 , 92 , 93 as gate circuits, and fourth through Nth OR circuits are omitted to simplify the illustration. Each of the OR circuits 91 , 92 , 93 , . . . N include a NOR gate and an inverter. Input data is supplied to one of two inputs of each of the NOR gates of the respective OR circuits 91 , 92 , 93 , . . . N from the corresponding one of the data input terminals, and an output from a NOR gate 51 is inputted in the other input of each of the NOR gates of the respective OR circuits 91 , 92 , 93 , . . . N. The internal control signal C bar that is internally generated in the internal circuit 30 is supplied through an inverter 52 to one of two inputs of the NOR gate 51 , and the test mode signal TEST is supplied to the other input of the NOR gate 51 . The inverter 52 inverts the internal control signal C bar to form an internal control signal C. The NOR gate 51 provides a logical sum of the internal control signal C and the test mode signal TEST, inverts its result and outputs the same.
[0038] When the internal control signal C bar is normally at high level in a test mode, the test mode signal TEST is at high level, and therefore an output of the NOR gate 51 is at low level. As a result, when logic levels on the data input terminals 1 , 2 , 3 , . . . , N are changed, outputs of the gate circuits 91 , 92 , 93 , . . . , N are accordingly changed.
[0039] The semiconductor device of the second embodiment has AND circuits 21 , 22 , 23 , . . . , N, each including a NAND gate and an inverter, a selection circuit 70 , and an output terminal 80 , in a similar manner as the first embodiment. Also, the semiconductor device of the second embodiment measures the logic levels of inputs to the internal circuit 30 in a similar manner conducted in the first embodiment.
[0040] It is noted that, in the exemplary embodiments described above, one type of internal control signal is used. However, the present invention is also applicable to other cases in which a plurality of internal control signals are used. In such cases, OR circuits in FIG. 1 or NOR gates 51 and inverters 52 in FIG. 2 may be provided in the same number of the internal control signals, respectively.
[0041] In accordance with the present invention, even when a gate circuit that uses an internal control signal is used in one of the input circuits in the first stage thereof, the operation of the gate circuit can be controlled by using a test mode signal. Therefore, the logic level of an input in the input circuits can be measured by using a test apparatus such as an IC tester.
[0042] While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention.
[0043] The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | A semiconductor device is provided having an internal circuit in which input data is gated and supplied to the internal circuit according to an internal control signal generated within the semiconductor device. The semiconductor device has N number (N being two or greater integers) of data input terminals for inputting input data, and a test mode input terminal for inputting a test mode signal. An OR device is provided for obtaining a logical sum of the internal control signal and the test mode signal. The semiconductor device also has N number of gate circuits that are supplied with the input data applied to the N data input terminals, respectively. When an output of the OR device is active, those of the N gate circuits responsive to the output of the OR device pass the input data applied to the data input terminals. The internal circuit is supplied with outputs of the N gate circuits. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for detecting simultaneous presentation of multiple documents. It particularly relates to such an apparatus used to detect the presence and passage of multiple documents along a track. The invention is hereinafter described with reference to its use in a document encoding machine wherein documents are passed along a track from an input pocket to one or more output stacks. It is to be understood that the present invention is not limited by this example to such particular use.
SUMMARY OF THE INVENTION
In a document encoding machine cheques or other documents are extracted one-by-one from an input pocket or stack to be sent along a track along which various reading or printing operations are executed upon the document. The processed document is then deposited in one or more output pockets. Typically the documents are sorted by type into the output pockets.
The extraction of documents, one-by-one from an input pocket, is not a perfect process. From time to time two or more documents can simultaneously be extracted from the input stack and sent along the track. When this happens, either the unwanted document passes undetected and unprocessed along the track, or else malfunction of the various document processing stages along the track occurs.
In the prior art it is known to shine a beam of light across the path of an oncoming document. If more than one downward step change in intensity of transmitted light across the document occurs, it is known that multiple documents have been presented to the track. It is then the normal procedure to stop the track and remove the multiple documents to be replaced in the input stack or pocket for reprocessing. If the documents have their leading edges aligned there is no way that multiple downward steps in transmitted light intensity can be detected since the multiple steps all occur at the same instant. The present invention seeks to overcome these difficulties.
The present invention consists in an apparatus for detecting simultaneous presentation of multiple documents having a multiple document detector set comprising: a driven member for imparting motive force to a document; an idler member, opposed to said driven member and co-operative with said driven member to grip documents there-between; and a velocity monitor; said driven member having a coefficient of friction against documents greater than the coefficient of friction of documents against each other; said idler member having a coefficient of friction against documents greater than the coefficient of friction of documents against each other; said idler member providing a document movement opposing force sufficient, when multiple documents are present between said idler member and said driven member, to cause sliding between documents; and said monitor monitoring relative peripheral velocity between said driven member and said idler member and providing a first output indicative of presentation of multiple documents when there is a difference between said relative peripheral velocities.
In the prior art it is known to stop the document track for extraction of a document for reprocessing, the present invention seeks to provide continuous document movement without stopping in an apparatus wherein a driven wheel is operative to continue to provide the motive force after the provision of the first output by the velocity sensor to cause separation between multiple presented documents. The present invention further seeks to provide improvement over the prior art by arranging that the velocity monitor, having once provided the first output indicative of the presence of multiple documents, is thereafter operative to provide a second output indicative of completion of document separation when the peripheral velocity of the driven wheel is equal to the peripheral velocity of the idler wheel.
The present invention further seeks to provide improvement over the prior art by providing a positive document separation facility along the track. The apparatus is provided with further document moving means operative to grasp a document from between the driven wheel and the idler wheel and to move the received document with a linear velocity greater than the peripheral velocity of the driven wheel. It is also a feature of the present invention that the further document moving means is inhibited from moving a document from between the driven wheel and the idler wheel with increased velocity until the velocity sensor provides a second output indicative of completion of document separation. Preferably, the present invention provides that the second document moving means comprises a second multiple document detector set. In the preferred embodiment the second multiple document detector set can select either a high peripheral velocity for the idler wheel and for the driven wheel or can select a standard peripheral velocity for the idler wheel and for the driven wheel equal to the peripheral velocity of the idler wheel and the driven wheel in the first or feeder multiple document detector set. When the first multiple document detector set indicates that it has detected multiple documents, the peripheral velocity of the driven wheel in the second multiple document detector set is set to the standard value equal to the peripheral velocity of the driven wheel in the first multiple document detector set. Once the first multiple document detector set indicates that it has completed separation of documents, this fact is signalled to the second multiple document detector set which sets the motor speed to drive the now separated document away from following documents with a higher velocity. In this way multiple documents are separated one from another along the track.
In one preferred embodiment of the invention the driven wheel is driven by a stepping motor receiving its stepping instructions from a monitor. The idler wheel has an idler wheel shaft encoder. The monitor compares the output of the shaft encoder with the number of steps administered by the stepping motor and provides a first output indicative of multiple documents if the peripheral velocities are not equal, and provides the second output, indicative of completion of separation of documents, if the peripheral velocities of the idler wheel and the driven wheel once again become equal. In another preferred embodiment of the invention, the motor is an ordinary motor which is speed regulated, and the driven wheel has a shaft upon which a driven wheel shaft encoder is mounted. The outputs from the driven wheel shaft encoder and the idler shaft encoder are compared by the monitor to determine whether a difference in peripheral velocity exists between the idler wheel and the driven wheel.
The present invention also provides that the monitor monitors the velocities of the driven wheel and of the idler wheel to determine whether or not a document is jammed in the track.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is further explained, by way of example, by the following description taken in conjuction with the appended drawings in which:
FIG. 1 shows a schematic block diagram of a multiple document detector set.
FIG. 2 is a projected view of a document moving along a document track with a second, multiple unwanted document shown in phantom outline.
FIG. 3 is a plan view of a multiple document detection station.
FIG. 4 is a side elevation of FIG. 3 looking in the direction of arrow X.
FIG. 5 is a side elevation of FIG. 3 looking in the direction of arrow Y.
FIG. 6 is a representative circuit capable of use with a shaft encoder as illustrated in FIGS. 4 and 5.
FIG. 7 is a flow chart representing the operation of the monitor of FIG. 1.
FIG. 8 is a plan view of an embodiment of the present invention wherein two document detector sets are provided in tandem.
FIG. 9 is a schematic block diagram of the embodiment of FIG. 8 showing the inter-relationship between monitors.
FIG. 10 is a flow chart illustrating the behaviour of the monitors in FIG. 9.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a schematic diagram of a multiple document detector set 10. A document track 12 (as will hereinafter be described) has a driven wheel on one side and an enclosed idler wheel on the other. A driven wheel angular velocity transducer 14 provides a signal indicative of the angular velocity of the driven wheel, on output line 16, to a monitor 18. An idler wheel angular velocity transducer 20 provides input to the monitor 18 via an output line 22. The monitor in turn provides a motor drive output 24, a first signal output 26 indicative of multiple documents being present on the track, and a second signal output 28 indicative of multiple documents having been separated. These latter functions and these components will be clarified in the following description.
FIG. 2 shows the document track and the manner in which multiple documents can move down the track.
The track 12 has a groove or slot 30 wherein documents 32, 34 can move as indicated by arrow 36. In FIG. 2 a first document 32 is shown in solid line while a second, undesired document 34, accompanying the first document 32 and which should have been separately fed into the track 12, is shown in phantom outline. Should the leading edge 38 of the wanted document 32 and the leading edge 40 of the unwanted document 34 be in alignment, it is impossible, using optical means looking for multiple steps of light transmission, to detect the presence of both documents. It is the object of the present invention to provide means whereby such wanted and unwanted documents can be detected. The invention further seeks, in a further embodiment, to provide means whereby the wanted document 32 and the unwanted document 34 can be separated to progress along the track 12 for individual processing.
Referring to FIG. 3, a driven wheel 42 is opposed by an idler wheel 44 to form a nip 46 over the groove 30 in the track 12. The driven wheel 42 is driven by a motor 48, FIG. 5 to rotate as indicated by arrow 50 which in turn, except when multiple documents 32, 34 are present, causes the idler wheel 44 to rotate as indicated by arrow 52. A document, held in the nip 46, is urged to move in the track 12 as indicated by arrow 54.
In FIG. 4, the idler wheel 44 is shown mounted on an angled shaft 56 upon which an optical disc 58 bearing successive light transmitting and opaque areas is interactive with an idler wheel photodetector 60. The idler wheel photodetector 60 and the idler wheel optical disc 58 together form the idler wheel angular velocity transducer 20 of FIG. 1.
The idler wheel shaft 56 has a slipping clutch 62 generally comprising a first plate 64 on the idler wheel shaft 56 and a fixed second plate 66, urged by a spring 68 against the first plate 64 to cause a predetermined rotation-opposing torque to be applied to the idler wheel shaft 56. As the driven wheel 42 rotates, the idler wheel shaft 56 rotates as indicated by arrow 70.
In FIG. 5 the driven wheel 42 is shown mounted on a shaft 72 along with a driven optical disc 74 which, like the idler wheel optical disc 58, bears alternate circumferential light transmitting and opaque areas which are sensed by a photodetector 76.
As will hereinafter be described, if the motor 48 is a stepping motor, the driven wheel optical disc 74 and the driven wheel photodetector 76 can be omitted. The driven wheel optical disc 74 and the driven wheel photodetector 76 together form the driven wheel angular velocity transducer 14 of FIG. 1.
Referring to FIG. 6 a light emitting diode 78 is connected via a first resistor 80 between a source of power 82 and ground 84. The light emitting diode 78 emits light which passes through the optical disc 58, 74. A second resistor 86 connects the collector 88 of the photo-transister 90 to the source of power 82 and the emitter 92 of the phototransistor 90 is connected to ground 84. As the optical disc 58, 74 rotates it intermittently blocks the light from the light emitting diode 78 to switch the phototransistor 90 between conducting and non-conducting states. The second resistor 86 develops the current change in the phototransistor 90 into a voltage which is applied as a first input to a voltage comparator 94. The second input of the voltage comparator 94 is provided from a reference voltage 96 and the comparator 94 provides output 98 which is logically indicative of whether or not the voltage on the collector 88 of the phototransistor 90 is larger or smaller than the reference voltage 96. It is generally to be understood that the first resistor 80, the second resistor 86 and the voltage comparator 94 will be provided within the monitor 18 of FIG. 1. As the idler wheel 42 or the driven wheel 44 rotates, the number of pulses at the output 98 of the comparator 94 in any unit time is proportional to the angular velocity of the driven wheel 42 and the angular velocity of the idler wheel 44. The angular velocities of the driven wheel 42 and the idler wheel 44 are in turn proportional to the linear peripheral velocities they posses in the nip 46. The monitor 18 counts the number of comparator 94 output pulses 98 over unit time intervals both from the idler wheel photodetector 60 and from the driven wheel photodetector 76 to determine whether or not the peripheral velocities of the driven wheel 42 and the idler wheel 44 are the same. If the output pulse rate in each instance falls within predetermined limits, either by comparison against some absolute value or by comparison against one another, the monitor 18 deems the peripheral velocities of the driven wheel 42 and the idler wheel 44 to be the same. If however, the peripheral velocities are not equal by more than a small predetermined amount, the monitor 18 determines that the peripheral velocites of the driven wheel 42 and of the idler wheel 44 are not the same.
It is to be understood that, while the figures show the driven wheel 42 and the idler wheel 44 to be of the same diameter, this need not be the case. The idler wheel optical disc 58 and the driven wheel optical disc 74 can provide different numbers of output pulses 98 for each revolution of their respective wheel 42, 44. In the preferred embodiment both wheels 42, 44 are of the same diameter and the respective optical discs 58, 74 give the same number of output pulses 98 for each revolution of their respective wheels 42, 44. The present invention also encompasses the situation where different numbers of output pulses 98 are received for each revolution of each wheel 42, 44. In this instance the monitor 18 compares the numbers of received pulses against an expected ratio, and should the ratio of the pulses received from the idler wheel photodetector 60 deviate by more than a predetermined amount in its ratio from the number of output pulses from the driven wheel photodetector 76, the monitor 18 determines that the driven wheel 42 and the idler wheel 44 do not possess the same peripheral velocity in the nip 46.
It is to be understood that the driven wheel angular velocity transducer 14 and the idler wheel angular velocity transducer 20 can be of other forms. For example, motor tachometers can be employed and their relative output voltages compared. It is only necessary that the driven wheel angular velocity transducer 14 and the idler wheel angular velocity transducer 20 be capable of providing a signal which can be monitored and assessed by the monitor 18.
In one embodiment of the invention, the driven wheel angular velocity transducer 14 is entirely omitted. Instead, the motor 48 is a stepper motor. A stepper motor executes an amount of rotation proportional to the number of angular steps it is commanded to execute. The monitor 18 provides step commands to the motor 48 on the motor drive output 24. The monitor 18, at the same time, monitors the output from the idler wheel angular velocity transducer 20. If any discrepancy is discovered by the monitor 18 between the expected output from the idler wheel angular velocity transducer 20 in light of the rate of steps applied to the motor 48 and the actual output of the idler wheel angular velocity transducer 20, the monitor 18 determines that the peripheral velocities of the driven wheel 42 and of the idler wheel 44 at the nip 46 are not the same.
It is a requirement of the present invention that the monitor 18 be capable of monitoring the peripheral velocities of the driven wheel 42 and of the idler wheel 44.
The driven wheel 42 is urged against the idler wheel 44 as generally indicated by arrows X, Y (FIG. 3). The material of the driven wheel 42 and the idler wheel 44 are chosen such that the driven wheel 42 and the idler wheel 44 each possess a coefficient friction against a document which is greater than the coefficient of friction of a document against another document. Suitable materials for the driven wheel 42 and the idler wheel 44 include neoprene, silicon rubber and other elastic polymers. It is a matter of choice depending upon the type of documents which are to be processed, to select suitable materials for the driven wheel 42 and the idler wheel 44.
Referring to FIG. 4, the idler wheel 44 is shown angled simply for any document 32, 34 passing along the track 12 to be urged down into the groove 30 as it traverses the nip 46 by the angled rotation of the idler wheel 44. The idler wheel 44 and the driven wheel 42 not only serve to detect multiple documents in the groove 30 of the track 12, but also serve to move documents 32, 34 along the track 12 and the present invention contemplates that plural multiple document detector sets can be provided along the track 12 as the prime or sole motive means for documents 32, 34.
FIG. 7 is a flow chart illustrating the actions of the monitor 18 of FIG. 1. The routine is entered from a first start operation 100 when the document encoding equipment is switched on. Control is immediately passed to a first test 102. In the first test 102, as documents 32, 34 move along a track, the monitor 18 monitors the periphral velocities of the driven wheel 42 and of the idler wheel 44 to see if they are the same. If the peripheral velocities of the idler wheel 44 and the driven wheel 42 are the same, control is returned by the first test 102 back to itself. If the peripheral velocity of the driven wheel 42 is not equal to the peripheral velocity of the idler wheel 44, control is passed to a first operation 103. The first operation 103 causes the monitor 18 provide the first output signal 26 indicative of multiple documents being present in the nip 46. The difference in peripheral velocity is caused by the predetermined torque, provided by the slipping clutch 62 on the idler wheel 44, causing the idler wheel 44 to grip the document 32 nearest thereto, that document sliding against the document next adjacent thereto. The driven wheel 42 continues to drive forward the document 34 nearest to the driven wheel 42, whereas the document 32 adjacent to the idler wheel 44 is retarded. When the two documents 32, 34 slide against one another, a difference appears in peripheral velocities between the driven wheel 42 and the idler wheel 44. The peripheral velocity difference persists so long as there are multiple documents in the nip 46. The multiple documents 32, 34 are separated one from another along the groove 30 by the driving action of the driven wheel 42 and the retarding action of the idler wheel 44 and the mutual slip between documents.
The first operation 103 passes control to a second test 104 which checks to see if the peripheral velocity of the driven wheel 42 has once again become equal to the peripheral velocity of the idler wheel 44. If the peripheral velocities are still unequal, the second test 104 returns to control to itself. If the peripheral velocities have again become equal, the second test 104 passes control to a second operation 106. The second operation 106 causes the controller 18 to provide the second output signal 28 indicative of separation of documents having been completed. When the driven wheel 42 has caused the document 34 adjacent thereto to have slid past the document 32 adjacent to the retarded idler wheel 44, only the document 32 which has so far been adjacent to the idler wheel 44 will remain within the nip 46. When only one document 32 remains in the nip 46 the driven wheel 42 entrains the idler wheel 44 through the document 32 such that their peripheral velocities once more become equal. This is indicative, as shown in the second operation 106, of a completion of the process of document separation. Had there been more than two documents in the nip 46, equal peripheral velocity between the driven wheel 42 and the idler wheel 44 would not have been achieved until just one document 32 remained in the nip 46.
The second operation 106 passes control to a third test 108 which tests to see if the last document 32 has exited from the nip 46. This can be done by any means known in the art such as photo-optic detection of the presence of a document in the proximity of the nip 46. If the last document 32 has not cleared the nip 46 the third test 108 returns control to itself. If the last document 32 has cleared the nip 46 the third test 108 passes control to a fourth test 110 which, using means known in the art, as indicated for the third test 108, checks to see if a new document has entered the nip 46. If photo-optic or other means indicate that a new document has entered the nip 46, the fourth test 110 passes control back to the first test 102. If not, the fourth test 110 passes control back to itself.
It is seen that the mechanism of FIGS. 1, 3, 4, 5 and 7 acts not only to detect multiple documents in the nip 46 but also acts to separate those documents 32, 34 and send them along the groove 30 in the track 12 one-by-one.
A problem exists in that there may not be adequate linear separation between multiple documents which have been presented to the nip 46, which have been separated by the nip 46, and, having been separated, which are sent along the track 12 for further processing. FIG. 8 shows a plan view of one means according to the present invention whereby this difficulty may be overcome.
A first multiple document detector set 10 acts as a feeder set to a second multiple document detector set 10'. The separation along the track 12 between the first document detector set 10 and the second multiple document detector set 10' is less than the length of a document 32, 34. As multiple documents 32, 34 in the nip 46 of the first multiple document detector set 10 are separated, the leading edge 112 of the document 34 adjacent to the driven wheel 42 in the first multiple document detector set 10 passes into the nip 46' between the driven wheel 42' and the idler wheel 44' of the second multiple document detector set 10'.
FIG. 9 shows a schematic block diagram of the connections between the monitors 18, 18' respectively in the first multiple document detector set 10 and the second multiple document detector set 10'.
The first monitor 18, as well as providing a first signal output 26 indicative of the presence of multiple documents to the outside world, also provides the first signal output 26 as an input to the second monitor 18'. The second signal output 28 of the first monitor 18, as well as being provided to the outside world, is also provided as a signal input, indicative of completion of document separation, to the second monitor 18'. The second monitor 18' can in turn provide its first signal output 26' not only to the outside world but also as an input to a further monitor 18" and can provide its second signal output 28', not only to the outside world, but also as a signal input to the third monitor 18". It is contemplated that as many multiple document detector sets can be provided along the length of the track 12 as are necessary to transport documents 32, 34 along the entire length of the track.
FIG. 10 is a flow chart showing the actions of each monitor 18, 18', 18" in FIG. 9. The operation is entered from a start operation 114 when the equipment is first switched on. Control is passed immediately to a test 116 which checks to see if the preceding monitor (i.e. Item 18 is the preceding monitor to Item 18' in FIG. 9, and likewise Item 18' is the preceding monitor to Item 18") has provided its first signal output 26 indicative of multiple documents 32, 34 being present in the nip 46. If multiple documents are not present in the preceding nip 46, the second monitor 18' sets the velocity of the motor 48 in a third operation 118 to a standard value which is the same as the motor velocity for the motor driving the preceding driven wheel 42. Control is then passed back to the test 116. If the test 116 detects output 26 from the preceding monitor 18 indicative of multiple documents being present in the nip 46 of the first, feeding multiple document detector set 10, control is passed to operation 120 where the speed of motor 48 in the second multiple document detector set 10' is set to the same standard value. Thus, as the two documents 32, 34 are separated with one of the documents 34 gripped in both nips 46, 46', the document 34 passing through both nips 46, 46' is driven at the same speed by both nips 46, 46'.
The operation 120 passes control to test 122 which tests to see if the first or feeding controller 18 has provided the second signal output 28 indicative of document separation having been completed. If document separation is not complete, control is passed back to the operation 120. If document separation is complete control is passed to operation 124 where the controller 18' in the second multiple document detector set 10 sets the velocity of the motor 48 in the second multiple document detector set 10' to a higher value which momentarily causes the document 34 which has been separated from another document 32 to be accelerated along the track 12 to create a linear separation along the track 12 between it 34 and the following document 32. In this manner separated documents 32, 34 are spaced along the track 12.
In those instances where a separated document 34 encounters subsequent nips 46 wherein a documents is already present, the system simply adopts procedures once again to separate documents. Thus, if more than two documents are presented in the first nip 46, a plural string of multiple document detector sets 10 will separate the documents despite there being less distance between the nips 46, 46' than the length of a document 34.
The subsequent document detector set 10' can be replaced by a simple speed control acting in the manner of FIG. 10 as simple, further document moving means, still achieving linear document separation.
The motor 48 can be an ordinary electric motor driven at a controlled speed, in which instance the monitor 18 provides a signal determining the speed of the motor 48. The multiple document detector set 10 may comprise more than simply a driven wheel 42 and an idler wheel 44. For example, the driven wheel 42 and the idler wheel 44 may be accompanied by one or more traction belts and other items.
It is to be understood hereinbefore and hereinafter that, when reference is made to a driven wheel as the driven member 42 or to an idler wheel 44 as an idler member, reference is also included to systems including document transport belts, drive belts and the like. It is simply necessary in the present invention that the idler member provide a movement opposing drag and that separation by mutual sliding between documents can take place. The present invention also provides for an idler wheel to be urged against a driven belt, or for a driven wheel to be urged against a retarded belt, or for two belts to come together to form a document separating nip.
The present invention further provides that the monitor 18 18' is functional to monitor the peripheral velocities of the idler member or wheel and of the driven member or wheel to measure the linear velocities of documents along the track. | A multiple document detector set having a driven wheel and an opposed idler wheel for gripping documents in a pinch created there-between. The idler wheel (44) is provided with a slipping clutch (62) for creating a rotation opposing torque. The idler wheel (44) and the driven wheel (42) each have a coefficient of friction against documents greater than the coefficient of friction of documents against one another. When multiple documents are introduced into the nip (46) one document (32) is held by the idler wheel (44) and the other document (34) is driven by the driven wheel (42). A monitor (18) detects whether or not the driven wheel (42) has the same periphral velocity as the idler wheel (44) and signals the presence of multiple documents if the peripheral velocities are not the same. The monitor (18) signals completion of separation of multiple documents when the peripheral velocites once again become the same. Tandom provision of multiple document detectors sets (10) along the length of a track (12) insures that large numbers of documents (32,34) simultaneously presented in the track (12) can be separated. The multiple document detector sets (10) are provided as the prime or even sole motive force for documents (34,32) along the track (12). | 1 |
BACKGROUND OF THE INVENTION
[0001] Angiogenesis, the development of new blood vessels from an existing vascular bed, is a complex multistep process that involves the degradation of components of the extracellular matrix and then the migration, proliferation and differentiation of endothelial cells to form tubules and eventually new vessels. Angiogenesis is important in normal physiological processes including, by example and not by way of limitation, embryo implantation; embryogenesis and development; and wound healing. Excessive angiogenesis is also involved in pathological conditions such as tumour cell growth and non-cancerous conditions such as neovascular glaucoma, rheumatoid arthritis, psoriasis and diabetic retinopathy. The vascular endothelium is normally quiescent. However, upon activation, endothelial cells proliferate and migrate to form a primitive tubular network which will ultimately form a capillary bed to supply blood to developing tissues including a growing tumour.
[0002] The G-protein-coupled receptors (GPCR) form an important class of peptide-binding receptors. The various members of the GPCR family mediate a wide variety of intercellular signals. Members of the GPCR family have seven helical domains which span the cell membrane and are linked by three extracellular loops and three intracellular loops.
SUMMARY OF THE INVENTION
[0003] The invention provides assays for the identification of compounds useful for the modulation of angiogenesis. Such compounds are useful for the treatment of angiogenesis related diseases. The methods of the invention involve cell-free and cell-based assays that identify compounds which bind to and/or activate or inhibit the activity of HB-954, a G protein-coupled receptor. The assays are optionally followed by an in vivo assay of the effect of the compound on angiogenesis and/or angiogenesis related diseases.
[0004] In addition, the invention provides nucleic acid molecules comprising a nucleotide sequence encoding all or a portion of HB-954, polypeptides comprising all or a portion of HB-954, antibodies directed against HB-954.
[0005] The invention also describes compounds which bind to and/or activate or inhibit the activity of HB-954 as well as pharmaceutical compositions comprising such compounds.
[0006] The invention also provides pharmaceutical compositions comprising a compound identified using the screening methods of the Invention as a well as methods for preparing such compositions by combining such a compound and a pharmaceutically acceptable carrier. Also within the invention are pharmaceutical compositions comprising a compound identified using the screening assays of the invention packaged with instructions for use.
DETAILED DESCRIPTION OF THE INVENTION
[0007] Surprisingly if was found that a GPCR, named HB-954, GenBank Accession number D38449 (see Example 1), has an endothelial preferred pattern of expression, and that levels of its mRNA are induced by two distinct proangiogenic pathways, ie. that of sphingosine-1-phosphate SPP sphingosine-1-phosphate and VEGF (see Table 1).
[0008] HB-954 is homologous to the Orexin Receptor family of GPCRs which recogize neuropeptide ligands. Surprisingly, the findings of the present invention now link the endothelial-specific GPCR HB-954, and its putative protein ligand to the biology of endothelial cells, and to the process of angiogenesis.
[0009] Hata et al. (Biochimica et Biophysica Acta Vol 1261(1) Mar. 14, 1995 pp 121-125) have originally described the full-length cDNA clone HB-954, isolated from a human fetal brain library. The amino acid sequence of HB-954 deduced by Hata et al. contains four putative glycosylation sites in the N-terminal part, seven presumed transmembrane domains, and a large cytosolic domain in the C-terminal part.
TABLE 1 Relative Levels of endothelial-specific GPCR mRNA expression detected with the 1834_at probe set on the Affymetrix HG U95A chip*. relative level of HB-954 mRNA expression tissue sample (from 3 independent experiments) quiescent EC 89.5 35.9 10.2 proliferating EC 92.4 123.4 29.1 SPP treated EC 156.1 174.4 119.9 VEGF treated EC 171.5 140.6 126.9 SPP + VEGF 160.6 84.8 242.1; treated EC 324.4 *Proliferating HUVECs were in continuous culture, all other HUVEC samples were synchronized by overnight incubation in growth factor depleted conditions and then stimulation with one of Sphingosine 1 Phosphate, VEGF or both for 6 hours. Negative values were adjusted to zero. All other cells and tissues tested with the exception of angiopoietin treated smooth muscle cells did not show detectable levels of expression.
Screening Assays
[0010] The present invention provides methods for identifying compounds which can be used for the modulation of angiogenesis and for the treatment of a angiogenesis related diseases. The methods entail identifying candidate or test compounds which bind HB-954 and/or have a stimulatory or inhibitory effect on the activity or the expression of HB-954. Preferably, the identification of candidate or test compounds is followed by further determining which of the compounds that bind HB-954 or have a stimulatory or inhibitory effect on the activity or the expression of HB-954 have an effect on angiogenesis in an in vivo assay (effective compounds of the invention).
[0011] Candidate or test compounds or agents which bind HB-954 and/or have a stimulatory or inhibitory effect on the activity or the expression of HB-954 are identified in assays that employ either cells which express a form of HB-954 (cell-based assays) or isolated HB-954 (cell-free assays). The various assays of the invention can employ a variety of forms of HB-954, such as full-length HB-954, a biologically active fragment of HB-954, or a fusion protein which includes all or a portion of HB-954.
[0012] The assay can be a binding assay entailing direct or indirect measurement of the binding of a test compound or known HB-954 ligand to HB-954.
[0013] Thus, in one aspect of the invention there is provided a method for identifying a compound useful for modulating angiogenesis, the method comprising the steps of: a) contacting a test compound with a HB-954 polypeptide and b) determining whether the test compound binds to the HB-954 polypeptide.
[0014] Binding of the test compound to the HB-954 polypeptide can be determined either directly or indirectly as described above. In one embodiment, the assay includes contacting the HB-954 polypeptide with a known compound which binds the HB-954 polypeptide to form an assay mixture, contacting the assay mixture with a test compound, and determining the ability of the test compound to interact with the HB-954 polypeptide, wherein determining the ability of the test compound to interact with the HB-954 polypeptide comprises determining the ability of the test compound to preferentially bind to the HB-954 polypeptide as compared to the known compound.
[0015] Preferred is a method wherein the binding to the HB-954 polypeptide is within a K D range of 10e −6 to 10e −13 preferably within a range of 10e −8 to 10e −12 .
[0016] The assay can be in a competitive binding format.
[0017] Thus, in a further aspect of the invention there is provided a method for identifying a compound useful for modulating angiogenesis, the method comprising: a) contacting a HB-954 ligand with a HB-954 polypeptide in the presence and absence of a test compound and b) determining whether the test compound alters the binding of the HB-954 ligand to the HB-954 polypeptide.
[0018] The assay can also be an activity assay, such as a cellular activity assay, entailing direct or indirect measurement of the activity of HB-954.
[0019] Thus, in another aspect of the Invention there is provided a method for identifying a compound useful for modulating angiogenesis, the method comprising: a) contacting a test compound with a cell expressing a HB-954 polypeptide and b) determining whether the test compound alters activity of the HB-954 polypeptide in said cell.
[0020] Determining the ability of the test compound to modulate the activity of the membrane-bound form of HB-954 can be accomplished by any method suitable for measuring the activity of HB-954, e.g., any method suitable for measuring the activity of a G-protein coupled receptor or other seven-transmembrane receptor.
[0021] The activity of a seven-transmembrane receptor can be measured in a number of ways, not all of which are suitable for any given receptor. Among the measures of activity are: alteration in intracellular Ca 2+ concentration, activation of phospholipase C, alteration in intracellular inositol triphosphate (IP 3 ) concentration, alteration in intracellular diacylglycerol (DAG) concentration, and alteration in intracellular adenosine cyclic 3′,5′-monophosphate (cAMP) concentration.
[0022] It can also be accomplished, for example, by determining the ability of HB-954 to bind to or interact with a target molecule. The target molecule can be a molecule with which HB-954 binds or interacts with in nature, for example, a molecule on the surface of a cell which expresses HB-954, a molecule on the surface of a second cell, a molecule in the extracellular milieu, a molecule associated with the internal surface of a cell membrane or a cytoplasmic molecule. The target molecule can be a component of a signal transduction a pathway which facilitates transduction of an extracellular signal (e.g., a signal generated by binding of a HB-954 ligand to HB-954) through the cell membrane and into the cell. The target molecule can be, for example, a second intracellular protein which has catalytic activity or a protein which facilitates the association of downstream signaling molecules with HB-954. A HB-954 ligand is one example of a HB-954 target molecule.
[0023] The screening assays of the invention may be combined with an in vitro or vivo assay entailing measuring the effect of the test compound on angiogenesis or angiogenesis related diseases.
[0024] Thus, the above methods of the invention may further comprise the steps of: c) adding a compound identified by a method of the invention to an assay for modulation of angiogenesis; d) determining whether the compound modulates angiogenesis; and e) identifying a compound that modulates angiogenesis as a compound useful for the treatment of angiogenesis related diseases.
[0025] As described in greater detail below, the test compound can be obtained by any suitable means, e.g., from conventional compound libraries. In one embodiment, the invention provides assays for screening candidate or test compounds which bind to or modulate the activity of a membrane-bound form of HB-954. Determining the ability of the test compound to bind to a membrane-bound form of HB-954 can be accomplished, for example, by coupling the test compound with a radioisotope or enzymatic label such that binding of the test compound to the HB-954-expressing cell can be measured by detecting the labeled compound in a complex.
[0026] In various embodiments of the above assay methods of the present invention, it may be desirable to immobilize the HB-954 polypeptide (or a HB-954 target molecule) to facilitate separation of complexed from uncomplexed forms of one or both of the proteins, as well as to accommodate automation of the assay. Binding of a test compound to the HB-954 polypeptide, or interaction of the HB-954 polypeptide with a target molecule in the presence and absence of a candidate compound, can be accomplished by methods well known in the art.
[0027] The screening assay can also involve monitoring the expression of HB-954. For example, modulators of expression of HB-954 can be identified in a method in which a cell is contacted with a candidate compound and the expression of HB-954 protein or mRNA in the cell is determined. The level of expression of HB-954 protein or mRNA the presence of the cadidate compound is compared to the level of expression of HB-954 protein or mRNA in the absence of the candidate compound. The candidate compound can then be identified as a modulator of expression of HB-954 based on this comparison. For example, when expression of HB-954 protein or mRNA protein is statistically significantly greater in the presence of the candidate compound than in its absence, the candidate compound is identified as a stimulator of HB-954 protein or mRNA expression. Alternatively, when expression of HB-954 protein or mRNA is statistically significantly less in the presence of the candidate compound than in its absence, the candidate compound is identified as an inhibitor of HB-954 protein or mRNA expression. The level of HB-954 protein or mRNA expression in the cells can be determined by methods described below.
[0000] Angiogenesis Related Diseases and Angiogenesis Models
[0028] “Angiogenesis related diseases” within the meaning of the invention include but are not limited to coronary artery disease, peripheral vascular disease, wound healing, islet cell transplantation, fracture and tendon repair, reconstructive surgery, tissue engineering, restenosis, cancer, age-related macular degeneration, diabetic retinopathy, rheumatoid arthritis, psoriasis, obesity, hemangioma/AIDS-related kaposi's sarcoma, atherosclerotic plaque rupture.
[0029] In a preferred embodiment effective compounds identified with the assays of the invention further described herein primarily inhibit the growth of blood vessels and are thus, for example, effective against a number of diseases associated with deregulated angiogenesis, especially diseases caused by ocular neovascularisation, especially retinopathies, such as diabetic retinopathy or age-related macular degeneration, psoriasis, haemangioblastoma, such as haemangioma, mesangial cell proliferative disorders, such as chronic or acute renal diseases, e.g. diabetic nephropathy, malignant nephrosclerosis, thrombotic microangiopathy syndromes or transplant rejection, or especially inflammatory renal disease, such as glomerulonephritis, especially mesangio-proliferative glomerulonephritis, haemolytic-uraemic syndrome, diabetic nephropathy, hypertensive nephrosclerosis, atheroma, arterial restenosis, autoimmune diseases, acute inflammation, fibrotic disorders (e.g. hepatic cirrhosis), diabetes, neurodegenerative disorders and especially neoplastic diseases (solid tumours, but also leukemias and other “liquid-tumours”, especially those expressing c-kit, KDR or flt-1), such as especially breast cancer, cancer of the colon, lung cancer (especially small-cell lung cancer), cancer of the prostate or Kaposi's sarcoma. An effective compound of the invention may inhibit the growth of tumours and is especially suited to preventing the metastatic spread of tumours and the growth of micrometastases.
[0030] The angiogenesis modulating activity of the compound can be tested in vitro by a variety of methods such as endothelial cell migration, proliferation, apoptosis, and tube formation. Additionally, more complex ex vivo (Nicosia R. F. and Ottinetti, A. Laboratory Investigation, 63, p115-122, 1990) and in vivo models can be used to assess the activity of angiogenesis modulating compounds (reviewed in Nat Med November 1997;3(11):1203-8). Common models for this include:
1. The matrigel angiogenesis model in which angiogenic: Ancellin N. et al., J. Biol. Chem. 277, 6667-6675, 2002. 2. The corneal pocket assay: Gimbrone, M. A. J., et al., J. Natl. Cancer Inst. 52, 413-427, 1974 3. The chick embryonic chorioallantoic membrane assay: Nguyen, M., et al., Microvascular Research, 47, 31-40, 1994.
[0034] The efficacy of the compounds of the invention as it relates to coronary artery disease and peripheral vascular diseases can be modeled as follows. The most commonly used coronary disease models is an ameroid constriction model (Lamping, K A at el., J. Pharmacol Exp. Ther 229, 359-363, 1984). A second model that may mimic the human condition more accurately is a repetitive occlusion model (Kersten J R et al., American J. Physiol. 268, H720-728, 1995). Rabbit, rat, and mouse have been used to model peripheral vascular diseases (Hershey J C et al., Cardiovascular Research 49, 618-625, 2001 and Mack C A et., J. Vascular Surgery, 27, 699-709, 1998).
[0035] The efficacy of the compound s of the invention as it relates to age-related macular degeneration or to diabetic retinopathy can be demonstrated in vivo as follows:
[0036] In vivo inhibition of choroidal neovascularization is modeled by a laser photocoagulation to rupture Bruch's membrane (Mori et al., American J. of Pathology, 159, 313-320, 2001). Ischemic retinopathy is modeled by first placing neonatal mouse in an hyperoxia environment with subsequent return to normal oxygen tension (Smith L E H et al., Invest. Ophthalmol. Vis. Sci. 35,101-111, 1994).
[0037] The antitumor efficacy of the compounds of the invention can be demonstrated in vivo as follows: In vivo activity in the nude mouse xenotransplant model: female BALB/c nude mice (8-12 weeks old), Novartis Animal Farm, Sisseln, Switzerland) are kept under sterile conditions with water and feed ad libitum. Tumors are induced either by subcutaneous injection of tumor cells into mice (for example, Du 145 prostate carcinoma cell line (ATCC No. HTB 81; see Cancer Research 37, 4049-58 (1978)) or by implanting tumor fragments (about 25 mg) subcutaneously into the left flank of mice using a 13-gauge trocar needle under Forene® anaesthesia (Abbott, Switzerland). Treatment with the test compound is started as soon as the tumor has reached a mean volume of 100 mm 3 . Tumor growth is measured two to three times a week and 24 hours after the last treatment by determining the length of two perpendicular axes. The tumor volumes are calculated in accordance with published methods (see Evans et al., Brit. J. Cancer 45, 466-8 [1982]). The antitumor efficacy is determined as the mean increase in tumor volume of the treated animals divided by the mean increase in tumor volume of the untreated animals (controls) and, after multiplication by 100, is expressed as T/C %. Tumor regression (given in %) is reported as the smallest mean tumor volume in relation to the mean tumor volume at the start of treatment. The test compound is administered daily by gavage.
[0038] As an alternative other cell lines may also be used in the same manner, for example:
the MCF-7 breast adenocarcinoma cell line (ATCC No. HTB 22; see also J. Natl. Cancer Inst. (Bethesda) 51, 1409-16 [1973]); the MDA-MB 468 breast adenocarcinoma cell line (ATCC No. HTB 132; see also In Vitro 14, 911-15 [1978]); the MDA-MB 231 breast adenocarcinoma cell line (ATCC No. HTB 26; see also J. Natl. Cancer Inst. (Bethesda) 53, 661-74 [1974]); the Colo 205 colon carcinoma cell line (ATCC No. CCL 222; see also Cancer Res. 38, 1345-55 [1978]);. the HCT 116 colon carcinoma cell line (ATCC No. CCL 247; see also Cancer Res. 41, 1751-6 [1981]); the DU145 prostate carcinoma cell line DU 145 (ATCC No. HTB 81; see also Cancer Res. 37, 4049-58 [1978]); and the PC-3 prostate carcinoma cell line PC-3 (ATCC No. CRL 1435; see also Cancer Res. 40, 524-34 [1980]).
[0046] The usefulness of a compound identified by the present invention in the treatment of arthritis as an example of an inflammatory rheumatic or rheumatoid disease can be demonstrated as follows:
[0047] The well-known rat adjuvant arthritis model (Pearson, Proc. Soc. Exp. Biol. 91, 95-101 (1956)) is used to test the anti-arthritic activity of compounds of the invention, or salts thereof. Adjuvant Arthritis can be treated using two different dosing schedules: either (i) starting time of immunisation with adjuvant (prophylactic dosing); or from day 15 when the arthritic response is already established (therapeutic dosing). Preferably a therapeutic dosing schedule is used. For comparison, a cyclooxygenase-2 inhibitor, such as 5-bromo-2-(4-fluorophenyl)-3-[4-(methylsulfonyl)phenyl]thiophene or diclofenac, is administered in a separate group.
[0048] In detail, male Wistar rats (5 animals per group, weighing approximately 200 g, supplied by Iffa Credo, France) are injected i.d. (intra-dermally) at the base of the tail with 0.1 ml of mineral oil containing 0.6 mg of lyophilised heat-killed Mycobacterium tuberculosis. The rats are treated with the test compound (3, 10 or 30 mg/kg p.o. once per day), or vehicle (water) from day 15 to day 22 (therapeutic dosing schedule). At the end of the experiment, the swelling of the tarsal joints is measured by means of a mico-calliper. Percentage inhibition of paw swelling is calculated by reference to vehicle treated arthritic animals (0% inhibition) and vehicle treated normal animals (100% inhibition).
[0049] On the basis of these studies, a compound identified by the present invention is appropriate for the treatment of inflammatory (especially rheumatic or rheumatoid) diseases.
[0050] In addition, there exist a number of transgenic models that are useful for angiogenesis and disease-relevant analyses e.g. cancer and cardiovascular diseases (reviewed in Hanahan D. et al., European. J. Cancer 32A,2386-2393, 1996 Carmellet, P. and Collen, D., J. of Pathology, 190, 387-405, 2000).
[0000] Test Compounds
[0051] Suitable test compounds for use in the screening assays of the invention can be obtained from any suitable source, e.g., conventional compound libraries. The test compounds can also be obtained using any of the numerous approaches in combinatorial library methods known in the art, including: biological libraries; spatially addressable parallel solid phase or solution phase libraries; synthetic library methods requiring deconvolution; the “one-bead one-compound” library method; and synthetic library methods using affinity chromatography selection.
[0052] Modeling of Compounds
[0053] Computer modeling and searching technologies permit identification of compounds, or the improvement of already identified compounds, that can modulate HB-954 expression or activity. Having identified such a compound or composition, the active sites or regions are identified. Such active sites might typically be ligand binding sites. The active site can be identified using methods known in the art including, for example, from the amino acid sequences of peptides, from the nucleotide sequences of nucleic acids, or from study of complexes of the relevant compound or composition with its natural ligand. In the latter case, chemical or X-ray crystallographic methods can be used to find the active site by finding where on the factor the complexed ligand is found.
[0054] Next, the three dimensional geometric structure of the active site is determined. This can be done by known methods, including X-ray crystallography, which can determine a complete molecular structure. On the other hand, solid or liquid phase NMR can be used to determine certain intramolecular distances. Any other experimental method of structure determination can be used to obtain partial or complete geometric structures. The geometric structures may be measured with a complexed ligand, natural or artificial, which may increase the accuracy of the active site structure determined.
[0055] Finally, having determined the structure of the active site, either experimentally, by modeling, or by a combination, candidate modulating compounds can be identified by searching databases containing compounds along with information on their molecular structure. Such a search seeks compounds having structures that match the determined | The invention describes assays for the identification of compounds useful for the modulation of angiogenesis. The methods of the invention involve cell-free and cell-based assays that identify compounds which bind to and/or activate or inhibit the activity of HB-954, a G protein-coupled receptor, optionally followed by an in vivo assay of the effect of the compound on angiogenesis. The invention also describes compounds which bind to and/or activate or inhibit the activity of HB-954 as well as pharmaceutical compositions comprising such compounds. In addition, the invention includes nucleic acid molecules comprising a nucleotide sequence encoding all or a portion of HB-954, gene therapy vectors comprising such sequences, polypeptides comprising all or a portion of HB-954 and antibodies directed against HB-954. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates to modular bridge building systems and particularly to temporary modular bridge building systems.
REVIEW OF THE ART KNOWN TO THE APPLICANT
[0002] Presently if a river, body of water or other obstacle such as boggy ground is to be crossed, then a number of systems exist that allow the rapid building of a bridge to allow vehicles to cross the obstacle. One such bridging system is the pontoon bridge wherein the deck of the bridge is supported by a series of floating boats or pontoons which are either tied together, or fixed in position by attachment to the deck or to the river bottom. In recent times a number of powered floating vehicles have been used which can be connected together such that the decks of the vehicles form a bridge.
[0003] Another form of such a bridge is the bailey bridge which is composed of pre-fabricated building components typically made from steel or steel alloys. The building components are assembled together to form a bridge which spans across the obstacle.
[0004] The bridging systems described above all suffer from a common problem in that they are formed from large heavy components which are relatively difficult to transport.
[0005] A bridging system is therefore required which is lightweight to facilitate its transport and which is quick and simple to assemble. Such a bridging system is disclosed within.
SUMMARY OF THE INVENTION
[0006] In it broadest aspect, the invention provides a modular bridging system comprising modules which inter-link to form a deck suitable for use as a buoyant walkway or roadway; and in which the means for causing successive modules to interlink comprises pegs which, in use, joint the facing surfaces of adjacent modules allowing the modules a limited relative up-and-down linked movement and, which are readily detachable when the deck is to be dismantled. A system of this type may be readily made from lightweight material such as plastics material, such that the modules and pegs used to form the walkway or roadway are easily transported. Additionally, the modules and pegs may be quickly assembled or dismantled without the need to use heavy lifting equipment.
[0007] Preferably the facing surfaces of adjacent modules are in close juxtaposition. The close juxtaposition of the facing surfaces allows the walkway/roadway to be walked on without the risk of people's feet falling into the gap between adjacent modules.
[0008] Preferably the modules are shaped such that when not in use they can be stored in a nested stack. The formation of a nested stack of modules enables the modules to be stacked one inside another, the nesting of modules in this way giving rise to a stack of modules which are more stable when stood upon each other.
[0009] The formation of a nested stack reduces the space required to store the modules. A stack of nested modules also have an increased stability as compared to a series of modules which are simply stacked one on top of the other. It is also worth noting that the upper and lower faces, in use, of the modules may incorporate ridges and corresponding indentations which allow the upper and lower faces to interengage as a means of improving the stability of a stack of modules whether they are nested or not.
[0010] Preferably the modules incorporate one or more orifices to allow the insertion of one or more poles which attach to plates such that a stack of the modules can be sandwiched between two such plates to form an assembly for storage purposes. In this way a stack of modules may be held together to form a single unit which may be readily moved rather than having to move separate modules one at a time.
[0011] Preferably the pegs incorporate a locking mechanism to lock the pegs to the modules. The use of pegs which incorporate a locking mechanism ensures that the pegs are not accidentally ejected from the point where they joint adjacent modules.
[0012] Preferably the pegs utilise a releaseable locking mechanism. The use of a releasable locking mechanism enables a bridge to be built from the modular bridging system described herein to be readily dismantled for transport to other locations.
[0013] Preferably the modules have a wider cross-section at their upper face, in use, than at their lower face. In this way a deck can be formed wherein the upper facing surfaces, in use, of adjacent modules may fit closely together whilst a gap is provided between adjacent lower facing surfaces which facilitates the passage of water around the interlinked modules.
[0014] Preferably, at least some of said modules have a tapered shape (with a narrow, and preferably pointed end, and a broad end) in plan view, in use. Modules incorporating the tapered shape may be used at the outer edges of the deck, with the narrow or pointed end facing in the direction of a water flow and away from the direction of the water flow.
[0015] The provision of modules with a tapered shaped at the outer edge facing in the direction of the water flow assists (i.e. upstream) the flow of water around and through the interlinked modules. The tapered shape of modules facing away from the direction of the water flow (i.e. downstream) helps to reduce the formation of eddies around the modules, further assisting the flow of water through and around the interlinked modules.
[0016] Preferably at least the sides, in use, of the modules are produced from a flexible, and preferably an elastomeric material. The production of the sides of the modules from flexible material, combined with at least the upper surface, in use, or potentially the upper and lower surfaces, in use, being made from a rigid material, provides a module which may be inflated for use and deflated for storage purposes, thus reducing the volume occupied by the modules for storage purposes. Elastomeric materials give further resilience to the units, and increased capacity for shock absorbance.
[0017] Preferably the system includes means to allow the modules to be at least partially deflated. It may be particularly useful when using the bridging system on uneven marshy ground to provide a module that compresses when a load is applied to the module. This compression is enabled by the expulsion of air from the module (i.e. deflation) due to the applied load. The module resumes its original shape once the applied load is removed.
[0018] Preferably the pegs incorporate one or more openings to assist the flow of water through the pegs. This feature further assists the flow of water through and around the interlinked modules reducing the overall resistance of the interlinked modules to the flow of water.
[0019] Preferably the pegs are sized such as to enable a selective increase or decrease of the distance between adjacent modules in use. The pegs may incorporate a central section, the size of said section being increased or decreased such that the spacing between adjacent modules may be increased or decreased.
[0020] Preferably panels are provided which fix to the upper surface, in use, of one or more modules and wherein successive panels interlock in a manner which provides additional rigidity to a deck formed from modules and panels. The use of interlocking panels in this way allows loads applied to an individual panel to be spread over a larger number of modules than would be the case if the load was applied directly to the modules. Thus the bridging system incorporating modules used in combination with panels provides improved buoyancy as compared to the system wherein the panels are not used.
[0021] In any aspect of the invention there is provided a module suitable for building a modular bridging system in accordance with any preceding claim and shaped such that when not in use it can interengage with one or more identical such modules to form a nested stack. The nesting of modules in this way reduces the volume of space occupied by the modules during storage.
[0022] In any aspect of the invention there is provided a peg suitable for building a modular bridging system characterised by the feature that the peg is generally I-shaped in cross-section. The I-shape of the pegs allows limited movement of adjacent modules in a vertical direction whilst preventing horizontal movement between adjacent modules.
[0023] Included within the scope of the invention is a modular bridging system as described herein with reference to and/or as illustrated by any appropriate combination of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a schematic perspective view of the upper face, in use, of a module according to the present invention.
[0025] FIG. 2 is a schematic perspective view of the lower face, in use, of a module according to the present invention
[0026] FIG. 3 is a schematic plan view of the upper face, in use, of a module according to the present invention.
[0027] FIG. 3A is a schematic plan view of the lower face, in use, of a module according to the present invention.
[0028] FIG. 4A is a schematic perspective view of two plates 4 and their associated poles used to form an assembly of stacked modules.
[0029] FIG. 4B is a schematic representation of an assembly formed from plates and associated poles and modules.
[0030] FIG. 5 is a schematic side view of a module according to the present invention.
[0031] FIG. 6A is a schematic side view of a peg according to the present invention.
[0032] FIG. 6B is a schematic front view of a peg according to the present invention.
[0033] FIG. 6C is a schematic plan view of the upper surface, in use, of a peg according to the present invention.
[0034] FIG. 6D is a schematic perspective view of a peg according to the present invention.
[0035] FIG. 7 is a schematic perspective view of a module with a section which is tapered in shape according to the present invention.
[0036] FIG. 7A is a schematic plan view of a module with a section which is tapered in shape according to the present invention.
[0037] FIG. 8 is a schematic perspective view of a reinforcing strut suitable for use with modules according to the present invention.
[0038] FIG. 9 a is a schematic view of a module which can be nested and which also incorporates an elastomeric diaphragm.
[0039] FIG. 9 is a schematic side view showing a stack of nested modules.
[0040] FIG. 10 is a schematic perspective view of an alternative embodiment of a module
[0041] FIG. 11 is a schematic plan view of a deck assembled using modules according to the present invention.
[0042] FIG. 12 is a schematic perspective view of a panel suitable for fixing to a deck formed according to the present invention.
[0043] FIG. 13 is a schematic plan view showing part of a deck formed according to the present invention wherein panels are shown which are attached or in the process of being attached to the deck.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0044] Referring initially to FIG. 1 , there is shown module 10 suitable for the construction of a modular bridging system, the module being manufactured principally from a plastics material, such as polyethylene, by a rotational moulding operation. The walls of the module 10 are thin in relation to their overall size such that the modules are hollow and filled with air such that they are buoyant when immersed in water. The modules are also sealed to prevent the entry of water into their interior.
[0045] Referring to FIGS. 3 and 3A , it can be seen that the module further comprises four receiving portions 31 into which I-shaped shaped pegs, described later, can be inserted.
[0046] The module also incorporates four orifices (elongate circular channels) 32 which extend from the upper face 12 of the module to the lower face 15 of the module. The walls of the orifices 32 A may act as stiffeners when the modules are produced solely from rigid plastic material to improve the overall strength of the modules, such that they can stand greater loads.
[0047] Referring to FIG. 4B , poles may be inserted through the orifices 32 of a stack of inter-engaged modules 43 and two plates 41 attached to the ends of the poles, by known means, to maintain the inter-engagement of the modules by formation of an assembly of modules, thus facilitating the storage and transport of the modules. The plates 41 and associated poles 42 may be more clearly seen on FIG. 4A .
[0048] The orifices 32 may also be used as attachment points for the attachment of posts for signs, railings and the like.
[0049] The module has a pattern on its upper face 12 , see FIG. 1 , and a corresponding pattern 14 on the lower surface 15 which can be seen more clearly in FIG. 2 .
[0050] Referring to FIG. 5 , it can be seen that the patterns on the upper face 12 , in use, comprise raised portions 51 and lowered portions 52 . Similarly, the patterns on the lower face 15 , in use, comprise raised portions 54 and lowered portions 53 . The raised portions 51 , 54 and lowered portions 52 , 54 being generally elongate ridges as can be seen clearly on FIGS. 1 and 2 . The upper face 12 and lower face are patterned such that the upper face of a first module will interengage with the lower face of a second module when placed in appropriate alignment atop the first module.
[0051] Referring to FIG. 1 and FIG. 3 , secondary raised portions 56 are provided on the upper face, in use, of the modules 10 which interengage with secondary recessed portions 57 on the lower faces of adjacent modules. The lower face 15 , in use, of the module includes secondary raised portions 56 A which interengage with secondary recessed portions 57 A on the upper face of adjacent modules when the modules are stacked. This interengagement of the secondary raised portions 56 , 56 A and secondary recessed portions 57 , 57 A prevents lateral movement of the stacked modules along the length of the ridges.
[0052] Referring to FIG. 3A it can be seen that the lower face 15 of the module is narrower than the top face 12 of the module. The side walls 33 of the module are generally curved in cross-section as can be seen more clearly on FIGS. 1 , 2 and 5 .
[0053] Referring now to FIG. 6A there is shown a peg suitable for linking adjacent modules to each other. The peg 61 is generally I-shaped in cross-section as can be seen by reference to FIG. 6C . The peg 61 is tapered along its length, as can be seen in FIG. 6A . The peg 61 is sized such that it fits into the receiving portions 31 of adjacent modules.
[0000] The peg 61 further comprises a releasable locking mechanism in the form of two resiliently deformable pins 62 . The pins may be integrally formed with the peg 61 which is produced from plastics material or alternatively produced from material which is more readily resiliently deformable such as sprung steel which is then attached to the peg 61 by known means. The peg joins the modules together by interlocking with a receiving portion, in the form of a recess 55 as shown in FIGS. 1 , 3 and 5 , the recess narrows from the top face of the module, in use, towards the lower face of the module. The receiving portion 31 of the modules generally narrows from the top face 12 , in use, towards the lower face 15 in order to better accommodate pegs.
[0054] The central section of the pegs as indicated by 63 on FIG. 6C may be increased in size or decreased in size to increase or decrease the size between adjacent modules as required in use.
[0055] Reference is now made to FIG. 3 wherein eight fixing points 34 in the form of threaded holes are indicated. These fixing points 34 enable the direct attachment of panels to the upper faces 12 of the modules such that the modules may be attached directly to temporary walkways and roadways, leading up to and on to the modular bridging system. The fixing points 34 also allow the direct attachment of panels to the upper face 12 of a deck formed from modular bridging system described herein.
[0056] Referring to FIGS. 7 and 7A there is shown a module 71 which incorporates a portion 72 which is generally tapered in shape. The module is attachable on three sides to other modules by the use of pegs which insert into the receiving portions 31 . For the sake of clarity, the pattern on the upper face of the module is not shown on FIG. 7 .
[0057] FIG. 8 shows a reinforcing strut, generally indicated by 81 , suitable for use with modules according to the present invention. The strut 81 is made from rigid light weight material such as aluminium or rigid plastics material such as glass reinforced polyethylene. The strut 81 is elongate and has a rectangular cross-section, and further incorporates engagement means 82 which are shaped to engage with the receiving portions 31 of the modules. The strut 81 also incorporates a rigid attachment means 83 A and 83 B to connect a first strut to a second strut, such that the two struts are rigidly attached to each other and do not allow the deflection of struts relative to each other.
[0058] If the modules are being used to cross a waterway a first module may be attached to a bank 121 as shown in FIG. 11 of the waterway using known means not shown or by the use of a trackway used to form a roadway which approaches the bank 121 of the waterway; this may be done using the fixing points 34 . Additional modules 10 are then interlinked to the first module by the use of pegs 61 .
[0059] Subsequently further modules are interlinked using pegs 61 to provide a deck across the waterway to the opposite bank 122 . The modules adjacent the second bank 122 of the waterway may also be attached to the bank by the use of known means or by the use of trackway used to create a roadway approaching the second bank of the waterway. Additionally modules 71 incorporating tapered portions may be used on the outer edges of the deck facing towards and away from the direction of the waterflow, as shown in FIG. 11 .
[0060] The use of modules 71 A with a tapered section facing towards the direction of water flow (i.e. upstream) assists the flow of water around and through the interlinked modules.
[0061] The tapered shape of the modules facing away from the direction of water flow (i.e. downstream) reduces the formation of eddies around the modules 71 B thus further assisting the flow of water through and around the interlinked modules.
[0062] The flow of water through the assembly is further facilitated by the lower faces of the 15 being narrower than the upper faces 12 of the modules, such that when the modules are interlinked by the use of pegs 61 the upper faces 12 of the modules can be juxtaposed to each other whilst a gap exists between the lower faces 15 of the modules. The gap between the lower faces of the modules facilitates the flow of water through the interlinked modules.
[0063] The I-shape of the pegs 61 , as previously described, allows limited vertical movement of adjacent modules relative to one another whilst preventing horizontal movement between adjacent modules. Thus the modules forming the deck have a limited capability to tilt as loads are applied to one side of the module thus reducing the strain exerted on the pegs holding the relevant adjacent modules together.
[0064] A deck formed from the interlinking of the modules, as described, may be disassembled by disengaging the locking mechanisms 62 and then withdrawing the pegs from the receiving portions of adjacent modules.
[0065] In fast-flowing water, as the modules are inter-linked they may have a tendency to become deflected by the flow of water in the direction of the water flow, such deflection resulting in the pegs linking the modules together coming under excessive strain that may in exceptional circumstances result in the pegs snapping. A strut 81 of the type previously described may be attached to appropriate rigid support means on the bank of the waterway, by known means, and the modules then attached to the rigid support strut 81 and to then each other by the use of pegs. The means used to attach the strut to the bank may provide for vertical movement of the struts to accommodate rising and falling water levels. Similarly, if the modules are attached to the tracking or walkway used to approach the bridging system, then mechanisms may be incorporated to accommodate rise and fall in water level. The deck formed from the inter-linked modules being used to then allow the attachment of a second strut to the first by the use of rigid attachment means 83 A and 83 B. Further modules can then be attached to the second strut and to the deck formed of interlinked modules. This process being repeated until a deck is produced across the waterway, the strut being ultimately connected to a second rigid support on the second bank of the waterway. The modules may also be attached to the banks of the waterway or to the walkway/roadway used to approach the waterway. The use of a series of struts in this way forms a reinforcing means which prevents the deflection of the inter-connected modules by a flow of water. Further struts may be used in the same way at other points in a deck formed from inter-linked modules to further reinforce the rigidity of the deck formed. It may be that the reinforcing struts 81 are only required during the initial assembly of the deck formed from inter-linked modules and once the modules are linked and anchored to the two opposing banks the reinforcing struts 81 may be removed. Additionally in fast flowing water the central sections of the pegs 63 may be increased in size to space the modules 10 further apart such that the water can more easily flow around the modules. It may then be necessary to utilise a plate-like material to cover the top of the deck formed to prevent objects and the feet of people using the bridge from entering the space between adjacent modules.
[0066] In a particularly preferred embodiment the modular bridge building system as described herein is used in combination with the ‘Constructional Panels’ described in earlier PCT patent application PCT/GB2004/004200 (WO2005035874). The panels 131 disclosed therein, see FIG. 12 , are provided with holes 132 to enable the panels to be connected to the modules 10 via the fixing points 34 in the modules 10 by the use of bolts. The bolts are sized to fit through holes 132 in the panel and engage with the threaded holes/fixing points 34 in the modules 10 . The holes 132 may be countersunk (not shown) in the upper face (in use) of the panel such that the head of the fixing bolt used does not protrude above the surface of the panel 132 . The panel also incorporates bores 133 for the receipt of lock members as described in earlier PCT application WO2005035874.
[0067] In use, once two modules 10 have been interlinked to each other by use of a peg 61 a panel 131 can then be used to more rigidly connect the modules to each other by the use of 4 bolts which fit through the holes in the panel 131 and then screw into the fixing points 34 in the modules. Further modules are then connected to the first two modules and subsequently further panels 131 are attached to the first panel according to the methods disclosed in PCT/GB2004/004200, the panels being connected to the modules on which they are situated rest by the use of bolts. In this way the upper face of the modules 10 can be covered by the use of such panels so that no gaps exist between adjacent panels to provide a deck which can readily be used as a walkway or driveway, without the problem of feet or other objects becoming inserted between adjacent modules.
[0068] Referring now to FIG. 13 , there is shown part of a deck formed of modules 10 and modules incorporating tapered portions 71 the modules being held together by the use of pegs 61 . A panel 131 A has been fixed to modules 10 A and 10 B by the use of bolts inserted through the holes 132 in the panel and which then screw into the threaded holes/fixing points 34 in the modules 10 A and 10 B. Subsequently panel 131 B has been interengaged with panel 131 A, as shown, by the engagement of the relevant tongue and groove portions and is then locked to panel 131 A by the use of the lock members 134 A and 134 B. The panel 131 B is then attached to modules 10 A and 10 C by the use of bolts fitted through the holes 132 in the panel 131 B and fixed the modules below by the use of the threaded holes 34 . Panels may be interlocked by the inter-engagement of tongue and grooved portions of adjacent panels and so the lock members are not an essential component of this particular embodiment.
[0069] Panel 131 C has its right hand edge engaged with the left hand edge of panel 131 A, with respective tongues and grooves fitted together. As such panel 131 C is slidable with respect to panel 131 A in the direction of panel 131 B such that it engages with panel 131 B. Panel 131 B is then locked to panel 131 C by the use of locking members 134 C and 134 D. Panel 131 C once locked to panel 131 B is then fixed to module 10 D by the use of bolts inserted through the holes 132 in the panel the bolts are then screwed to the fixing points 34 in modules 10 C and 10 D. In this way a deck, formed by the upper surface of the panels is built up, the panels making up the deck being attached to each other as well being fixed to the modules on which they are situated. Each of the modules 10 in turn is attached to adjacent modules by the use of pegs 61 . In this way a particularly rigid modular bridging system is provided wherein when load is applied to the upper surfaces of the panels 131 (in use), the load is distributed by the panels to a plurality of modules 10 such that the buoyancy to support the load is distributed to a plurality of modules 10 enabling larger loads to be supported than could be supported by a single module 10 , or by a module connected to adjacent modules by the use of pegs 61 alone.
[0070] The use of panels in this way may negate the need to use the struts 82 , as previously described, in fast flowing water.
[0071] In an alternative embodiment the modules as generally indicated by 90 , on FIG. 9 are shaped to allow them to form a nested stack for storage purposes. The upper face 9 , in use, of the modules being sized to fit (nest) within the opening 92 provided in the lower side, in use, of the module, to produce a nested stack of modules. The nested stack may then be held together by the use of poles in conjunction with plates as previously described with respect to FIGS. 4A and 4B . Alternatively the modules may include a diaphragm, indicated by the dotted line 93 as shown on FIG. 9 a , which allows the modules when appropriately shaped, to insert further into the body of the module into which it is inserted. The diaphragm allowing air to be entered into or withdrawn from an interior of the module through a valve.
[0072] In another preferred embodiment as shown in FIG. 10 the side walls 33 A of the modules as generally indicated by 100 , are produced from an elastomeric plastic material and a valve 95 is incorporated into the upper face of the module. The upper section 112 of the module, which incorporates the upper face 12 A and the lower section 115 which incorporates the lower face, as generally indicated by 15 A are made from rigid plastics material to which the elastomeric plastic is attached. Clearly the receiving portions 31 A, where the pegs fit, must be made of rigid plastics material to ensure the relative position of adjacent modules is maintained. In this particular embodiment the orifices 32 may be omitted or alternatively the sides of the orifices may be produced from a elastomeric polymer. A module is therefore provided which may be inflated and deflated by the use of the valve 95 , such that the volume of the module may be minimised for storage and transport purposes. Additionally the provision of such valves allow the modules to be inflated to varying levels such that when a deck is assembled on boggy/uneven ground the deck formed by the modules has a level upper surface. The valve 95 may alternatively be incorporated into the side of upper section 112 and for multiple valves 95 A may be provided.
[0073] A valve or multiple valves may be provided which allow a steady stream of air to escape from the interior of the module when a load is applied to the upper face 12 A of the module such that a cushioning effect is provided by the compression of the module when used on marshy or boggy ground. Additionally this type of system may also assist in providing what is perceived to be a more level walkway/trackway over terrain which is in parts submerged and in other parts not submerged as air will be ejected more quickly from modules which are resting on solid ground. The interior of the module may comprise a first chamber and second chamber wherein the release of air only occurs from one of the chambers the other chamber remaining filled with air and thus buoyant during normal use of the module. The first chamber 101 being incorporated above the dashed line A-A and the second chamber 102 being below the dashed line A-A. Once the load is removed from the module 100 the module returns to its original decompressed position and in so doing filling with air. The return to the original decompressed position may be achieved by providing some form of spring within the first chamber 101 , which compresses under the application of a load to the upper face 12 A of the module and then expands once the load is removed. Alternatively the side wall 33 A may be made of an elastromeric polymer which returns to its uncompressed state following the removal of the load, wherein air re-enters the first chamber 101 through the valve 95 and/or valves 95 A. In a further embodiment the modules may be filled with expanded plastics foam, such as polyurethane, foam to improve the strength of the modules whilst maintaining their buoyancy. This type of foam filled module may be particularly useful on boggy ground where some of the modules may be on solid ground and hence come under greater loads than those modules which are immersed in water. | A modular bridging system comprising modules ( 10 ) which inter-link to form a deck suitable for use as a buoyant walkway or roadway; and in which the means for causing successive modules to interlink comprises pegs ( 61 ; FIG. 6 A- 6 D) which, in use, joint the facing surfaces of adjacent modules allowing the modules a limited relative up-and-down linked movement and, which are readily detachable when the deck is to be dismantled. | 4 |
PRIORITY CLAIM
[0001] This application claims priority to Non-Provisional patent application Ser. No. 10/852,167 entitled “DUAL FUNCTION PROSTHETIC BONE IMPLANT AND METHOD FOR PREPARING THE SAME” filed on May 25, 2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention is related to a prosthetic bone implant made of a hardened calcium phosphate cement having an apatitic phase as a major phase, and in particular to a prosthetic bone implant comprising a dense cortical portion bearing the majority of load and a porous cancellous portion allowing a rapid blood/body fluid penetration and tissue ingrowth.
[0004] 2. Description of the Related Art
[0005] It is advantageous if a prosthetic bone implant is bioresorbable and is supportive at the same time. Accordingly, an article made of calcium phosphate will be preferable than that made of a metal, if the former has strength which is comparable to a human cortical bone. One way of making such a bone implant is by sintering a calcium phosphate powder, particularly a hydroxyapatite (HA) powder, into a block material at a temperature generally greater than 1000° C. Despite the fact that the high temperature-sintered HA block material has an enhanced strength, the bioresorbability of the material is largely sacrificed, if not totally destroyed, due to the elimination of the micro- and nano-sized porosity during the sintering process.
[0006] The conventional spinal fusing device is composed of a metallic cage and a bioresorbable material disposed in the metal cage, for example the one disclosed in U.S. Pat. No. 5,645,598. An inevitable disadvantage of this fusion device is the sinking of the metallic cage sitting between two vertebrae to replace or repair a defect spinal disk, because the hardness and the relatively small size of the cage wear out or break the bone tissue, and in particular the endplate of the vertebra.
SUMMARY OF THE INVENTION
[0007] A primary objective of the invention is to provide a prosthetic bone implant free of the drawbacks of the prior art.
[0008] The prosthetic bone implant constructed according to the present invention is made of a hardened calcium phosphate cement having an apatitic phase as a major phase, which comprises a dense cortical portion bearing the majority of load and a porous cancellous portion allowing a rapid blood/body fluid penetration and tissue ingrowth.
[0009] The prosthetic bone implant of the present invention is made by a novel technique, which involves immersing an article molded from two different pastes of calcium phosphate cement (CPC), one of them having an additional pore-forming powder, in a liquid for a period of time, so that the compressive strength of the molded CPC article is significantly improved after removing from the liquid while the pore-forming powder is dissolved in the liquid, creating pores in a desired zone or zones of the molded article.
[0010] Features and advantages of the present invention are as follows:
1. Easy process for different shape and size of the prosthetic bone implant of the present invention, so that the outer circumferential dense portion thereof can sit over the circumferential cortical portion of a bone and the porous portion thereof can contact the cancellous portion of the bone adjacent to a bone receiving treatment. 2. The dense cortical portion of the prosthetic bone implant made according to the present invention exhibits a high strength comparable to that of human cortical bone (about 110-170 MPa). The strength is adjustable by adjusting process parameters. 3. The dense cortical portion of the prosthetic bone implant made according to the present invention contains significant amount of micro- and nano-sized porosity, that improves bioresorbability thereof. Conventional high temperature-sintered HA block, on the other hand, does not possess sufficient micro/nano-sized porosity and is not bioresorbable. 4. The porous cancellous portion of the prosthetic bone implant made according to the present invention possesses a porosity greater than 40% in volume, prepferably 40-90%, allowing rapid blood/body fluid penetration and tissue ingrowth, thereby anchoring the prosthetic bone implant. 5. A wide range of medical application includes bone dowel, spacer, cavity filler, artificial disc and fixation devices for spine and other locations, to name a few.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIGS. 1 a to 1 d show schematic cross sectional views of four different designs of prosthetic bone implants constructed according to the present invention.
[0017] FIGS. 2 a to 2 f are schematic cross sectional views showing steps of a method for preparing a prosthetic bone implant according to one embodiment of the present invention.
[0018] FIGS. 3 a and 3 b are schematic vertical and horizontal cross sectional views of a prosthetic bone implant prepared according to another embodiment of the present invention, respectively.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Preferred embodiments of the present invention includes (but not limited to) the following:
1. A prosthetic bone implant comprising a cortical portion having two opposite sides, and a cancellous portion integrally disposed in said cortical portion and being exposed through said two opposite sides, wherein said cortical portion comprises a hardened calcium phosphate cement has a porosity of less than 40% in volume, and said cancellous portion comprises a porous hardened calcium phosphate cement having a porosity greater than 20% in volume, and greater than that of said cortical portion. 2. The implant according to Item 1, wherein the cortical portion is in the form of a hollow disk, and the cancellous portion is in the form of a column surrounded by the hollow disk. 3. The implant according to Item 2 further comprising a transitional portion between said column and said hollow disk surrounding said central cylinder, which has properties range from those of said cancellous portion to said cortical portion. 4. The implant according to Item 1, wherein the cortical portion is in the form of a disk having one or more longitudinal through holes, and the cancellous portion is in the form of one or more columns surrounded by said one or more longitudinal through holes. 5. The implant according to Item 1, wherein said hardened calcium phosphate cement of said cortical portion comprises an apatitic phase as a major phase giving rise to broadened characteristic X-ray diffraction peaks in comparison with a high-temperature sintered apatitic phase. 6. The implant according to Item 5, wherein said broadened characteristic the X-ray diffraction peaks are at 2-Theta values of 25-27° and 30-35°. 7. The implant according to Item 1, wherein said hardened calcium phosphate cement of said cortical portion is prepared without a high temperature sintering. 8. The implant according to Item 1, wherein said hardened calcium phosphate cement of said cortical portion comprises an apatitic phase as a major phase having a Ca/P molar ratio of 1.5-2.0. 9. The implant according to Item 1, wherein said hardened calcium phosphate cement of said cancellous portion comprises an apatitic phase as a major phase giving rise to broadened characteristic X-ray diffraction peaks in comparison with a high-temperature sintered apatitic phase. 10. The implant according to Item 9, wherein said broadened characteristic the X-ray diffraction peaks are at 2-Theta values of 25-27° and 30-35°. 11. The implant according to Item 1, wherein said hardened calcium phosphate cement of said cancellous portion is prepared without a high temperature sintering. 12. The implant according to Item 1, wherein said hardened calcium phosphate cement of said cancellous portion comprises an apatitic phase as a major phase having a Ca/P molar ratio of 1.5-2.0. 13. The implant according to Item 1, wherein said cortical portion comprises 10-90% in volume of said implant. 14. The implant according to Item 1, wherein said cortical portion has a porosity of less than 30% in volume. 15. The implant according to Item 1, wherein said cancellous portion has a porosity greater than 40-90% in volume. 16. A method for preparing a prosthetic bone implant comprising a cortical portion having two opposite sides, and a cancellous portion integrally disposed in said cortical portion and being exposed through said two opposite sides, said method comprises the following steps:
a) preparing a first paste comprising a first calcium phosphate cement and a first setting liquid; b) preparing a second paste comprising a second calcium phosphate cement, a pore-forming powder and a second setting liquid; c) i) preparing a shaped article in a mold having two or more cells separated by one more partition walls comprising introducing said first paste and said second paste into said two or more cells separately, and removing said one or more partition walls from said mold, so that said second paste in the form of a single column or two or more isolated columns is integrally disposed in the first paste in said mold; or ii) preparing a shaped article comprising introducing one of said first paste and said second paste into a first mold to form an intermediate in said first mold, placing said intermediate into a second mold after a hardening reaction thereof undergoes at least partially, and introducing another one of said first paste ad said second paste into said second mold, so that said second paste as a single column or as two or more isolated columns is integrally disposed in the first paste in said second mold; d) immersing the resulting shaped article from step c) in an immersing liquid for a first period of time so that said pore-forming powder is dissolved in the immersing liquid, creating pores in said single column or said two or more isolated columns; and e) removing the immersed shaped article from said immersing liquid.
17. The method according to Item 16 further comprising
f) drying the immersed shaped article.
18. The method according to Item 16, wherein said pore-forming powder is selected from the group consisting of LiCl, KCl, NaCl, MgCl 2 , CaCl 2 , NaIO 3 , KI, Na 3 PO 4 , K 3 PO 4 , Na 2 CO 3 , amino acid-sodium salt, amino acid-potassium salt, glucose, polysaccharide, fatty acid-sodium salt, fatty acid-potassium salt, potassium bitartrate (KHC 4 H 4 O 6 ), potassium carbonate, potassium gluconate (KC 6 H 1 O 7 ), potassium-sodium tartrate (KNaC 4 H 4 O 6 .4H 2 O), potassium sulfate (K 2 SO 4 ), sodium sulfate, and sodium lactate. 19. The method according to Item 16, wherein said first calcium phosphate cement comprises at least one Ca source and at least one P source, or at least one calcium phosphate source; and said second calcium phosphate cement comprises at least one Ca source and at least one P source, or at least one calcium phosphate source. 20. The method according to Item 19, wherein said first calcium phosphate cement comprises at least one calcium phosphate source, and said second calcium phosphate cement comprises at least one calcium phosphate source. 21. The method according to Item 20, wherein said calcium phosphate source is selected from the group consisting of alpha-tricalcium phosphate (α-TCP), beta-tricalcium phosphate (β-TCP), tetracalcium phosphate (TTCP), monocalcium phosphate monohydrate (MCPM), monocalcium phosphate anhydrous (MCPA), dicalcium phosphate dihydrate (DCPD), dicalcium phosphate anhydrous (DCPA), octacalcium phosphate (OCP), calcium dihydrogen phosphate, calcium dihydrogen phosphate hydrate, acid calcium pyrophosphate, anhydrous calcium hydrogen phosphate, calcium hydrogen phosphate hydrate, calcium pyrophosphate, calcium triphosphate, calcium phosphate tribasic, calcium polyphosphate, calcium metaphosphate, anhydrous tricalcium phosphate, tricalcium phosphate hydrate, and amorphous calcium phosphate. 22. The method according to Item 21, wherein said first calcium phosphate cement and said second calcium phosphate cement are identical. 23. The method according to Item 22, wherein said first calcium phosphate cement and said second calcium phosphate cement are tetracalcium phosphate. 24. The method according to Item 16, wherein the first setting liquid and the second setting liquid independently are an acidic solution, a basic solution, or a substantially pure water. 25. The method according to Item 24, wherein said acidic solution is selected from the group consisting of nitric acid (HNO 3 ), hydrochloric acid (HCl), phosphoric acid (H 3 PO 4 ), carbonic acid (H 2 CO 3 ), sodium dihydrogen phosphate (NaH 2 PO 4 ), sodium dihydrogen phosphate monohydrate (NaH 2 PO 4 .H 2 O), sodium dihydrogen phosphate dihydrate, sodium dihydrogen phosphate dehydrate, potassium dihydrogen phosphate (KH 2 PO 4 ), ammonium dihydrogen.phosphate (NH 4 H 2 PO 4 ), malic acid, acetic acid, lactic acid, citric acid, malonic acid, succinic acid, glutaric acid, tartaric acid, oxalic acid and their mixture. 26. The method according to Item 22, wherein said basic solution is selected from the group consisting of ammonia, ammonium hydroxide, alkali metal hydroxide, alkali earth hydroxide, disodium hydrogen phosphate (Na 2 HPO 4 ), disodium hydrogen phosphate dodecahydrate, disodium hydrogen phosphate heptahydrate, sodium phosphate dodecahydrate (Na 3 PO 4 .12H 2 O), dipotassium hydrogen phosphate (K 2 HPO 4 ), potassium hydrogen phosphate trihydrate (K 2 HPO 4 .3H 2 O), potassium phosphate tribasic (K 3 PO 4 ), diammonium hydrogen phosphate ((NH 4 ) 2 HPO 4 ), ammonium phosphate trihydrate ((NH 4 ) 3 PO 4 .3H 2 O), sodium hydrogen carbonate (NaHCO 3 ), sodium carbonate Na 2 CO 3 , and their mixture. 27. The method according to Item 16, wherein step c-i) further comprises allowing said first paste and said second paste undergoing a hardening reaction in said mold. 28. The method according to Item 16, wherein step c-i) further comprises pressurizing said first paste and said second paste in said mold after removing said one or more partition walls from said mold to remove a portion of liquid from said first paste and said second paste, so that a liquid/powder ratio of said first paste and of said second paste decreases; and allowing said first paste and second paste undergoing a hardening reaction in said mold. 29. The method according to Item 16, wherein step c-ii) further comprises allowing said intermediate undergoing a hardening reaction in said first mold, and allowing said another one of said first paste and said second paste undergoing a hardening reaction in said second mold. 30. The method according to Item 16, wherein step c-ii) further comprises pressurizing said one of said first paste and said second paste in said first mold to remove a portion of liquid therefrom before the hardening reaction of said intermediate is completed; allowing said intermediate undergoing a hardening reaction in said first mold; pressuring said another one of said first paste and said second paste in said second mold, so that a liquid/powder ratio of said another one of said first paste and of said second paste decreases; and allowing said another one of said first paste and second paste undergoing a hardening reaction in said second mold. 31. The method according to Item 28, wherein said pressuring is about 1 to 500 MPa. 32. The method according to Item 30, wherein said pressuring is about 1 to 500 MPa. 33. The method according to Item 16, wherein the immersing liquid is an acidic aqueous solution, a basic aqueous solution, a physiological solution, an organic solvent, or a substantially pure water. 34. The method according to Item 33, wherein the immersing liquid comprises at least one of Ca and P sources. 35. The method according to Item 33, wherein the immersing liquid is a Hanks' solution, a HCl aqueous solution or an aqueous solution of (NH 4 ) 2 HPO 4 . 36. The method according to Item 16, wherein the immersing in step d) is carried out for a period longer than 10 minutes. 37. The method according to Item 16, wherein the immersing in step d) is carried out for a period longer than 1 day. 38. The method according to Item 16, wherein the immersing in step d) is carried out at a temperature of about 10 and 90° C. 39. The method according to Item 38, wherein the immersing in step d) is carried out at room temperature. 40. The method according Item 17 further comprising cleaning said immersed shaped article before said drying; and heating the resulting dried shaped article at a temperature between 50 and 500° C.
[0066] Four different designs of prosthetic bone implants constructed according to the present invention are shown in FIGS. 1 a to 1 d . In FIG. 1 a , the prosthetic bone implant of the present invention has a dense cortical portion D 1 in the tubular form and a porous cancellous portion P 1 formed in the central through hole of the tubular cortical portion D 1 . Both the dense cortical portion D 1 and the porous cancellous portion P 1 are made of a hardened calcium phosphate cement having an apatitic phase as a major phase. In FIG. 1 b , the prosthetic bone implant of the present invention has a dense cortical portion D 1 in the tubular form; a cylindrical porous cancellous portion P 1 in the center of the tubular cortical portion D 1 ; and an annular transitional portion P 2 connecting the tubular cortical portion D 1 and the cylindrical cancellous portion P 1 . The transitional portion P 2 is made of a hardened calcium phosphate cement having an apatitic phase as a major phase, and a porosity gradient increasing from the lower porosity of the cylindrical cancellous portion P 1 to the higher porosity of the tubular cortical portion D 1 , which may be formed in-situ during molding of two different two different CPC pastes, one of them having an additional pore-forming powder for forming the cylindrical cancellous portion P 1 , and another one being a regular CPC powder for forming the dense cortical portion D 1 . The porous cancellous portion P 1 may be in the forms of isolated columns surrounded by the dense cortical portion D 1 as shown in FIGS. 1 c and 1 d . Other designs are also possible in addition to those shown in FIGS. 1 a to 1 d.
[0067] A suitable method for preparing the prosthetic bone implant of the present invention includes placing a tubular partition wall 10 in a hollow cylindrical mold 20 , as shown in FIG. 2 a ; pouring a first paste comprising a calcium phosphate cement and a setting liquid in the annular cell and a second paste comprising the calcium phosphate cement, a pore-forming powder and the setting liquid in the central cell, as shown in FIG. 2 b ; removing the partition wall and pressing the CPC pastes before hardening, as shown in FIG. 2 c , wherein a portion of the setting liquid is removed from the gap between the mold 20 and the press 30 and/or holes (not shown in the drawing) provided on the press 30 . The CPC paste will undergo a hardening reaction to convert into apatitic phase. The hardened disk is removed from the mold and is subjected to surface finishing to expose the central portion hardened from the second paste, as shown in FIG. 2 d , followed by immersing in a bath of an immersing liquid as shown in FIG. 2 e , where the pore-forming powder is dissolved in the immersing liquid while the hardened CPC thereof gaining compressive strength. The immersing may last from 10 minutes to several days. The composite disk so formed is washed with water after being removed from the bath, and dried and heated in an oven to obtain the prosthetic bone implant as shown in FIG. 2 f . The heating is conducted at a temperature between 50 and 500° C. for a period of several hours to several days, which enhance the compressive strength of the cortical portion of the prosthetic bone implant.
[0068] An alternative method for preparing the prosthetic bone implant of the present invention from the same raw materials includes pouring the second paste in a first mold, pressing the second paste to remove a portion of the setting liquid from the second paste before the hardening reaction is completed, so that the liquid/powder ratio in the second paste decreases, and allowing the hardening reaction undergo in the mold for a period of time, e.g. 15 minutes starting from the mixing of the CPC powder, the pore-forming powder and the setting liquid, to obtain a cylindrical block having a diameter of 7 mm. Then, the cylindrical block is removed from the first mold, and placed in the center of a second mold having a diameter of 10 mm. The first paste is poured into the annular space in the second mold, and a press having a dimension corresponding to the annular shape is used to pressure the first paste to remove a portion of the setting liquid from the first paste before the hardening reaction is completed, so that the liquid/powder ratio in the first paste decreases. Again, the first paste will undergo a hardening reaction to convert into apatitic phase. The hardened cylinder having a diameter of 10 mm is removed from the second mold, followed by immersing in an immersing liquid, where the pore-forming powder contained in the second paste is dissolved in the immersing liquid while the hardened CPC thereof gaining compressive strength, to obtain the prosthetic bone implant of the present invention, as shown in FIGS. 3 a and 3 b . It is apparently to people skilled in the art that the prosthetic bone implant shown in FIGS. 3 a and 3 b can also be prepared by changing the sequence of the molding of the first paste and the second paste with modifications to the second mold used in this alternative method.
[0069] The following examples are intended to demonstrate the invention more fully without acting as a limitation upon its scope, since numerous modifications and variations will be apparent to those skilled in this art.
PREPARATIVE EXAMPLE 1
Preparation of TTCP Powder
[0070] A Ca 4 (PO 4 ) 2 O (TTCP) powder was prepared by mixing Ca 2 P 2 O 7 powder with CaCO 3 powder uniformly in ethanol for 24 hours followed by heating to dry. The mixing ratio of Ca 2 P 2 O 7 powder to CaCO 3 powder was 1:1.27 (weight ratio) and the powder mixture was heated to 1400° C. to allow two powders to react to form TTCP.
PREPARATIVE EXAMPLE 2
Preparation of Conventional TTCP/DCPA-Based CPC Powder (Abbreviated as C—CPC)
[0071] The resulting TTCP powder from PREPARATIVE EXAMPLE 1 was sieved and blended with dried CaHPO 4 (DCPA) powder in a ball mill for 12 hours. The blending ratio of the TTCP powder to the DCPA powder was 1:1 (molar ratio) to obtain the conventional CPC powder. Particles of this C—CPC powder have no whisker on the surfaces thereof.
PREPARATIVE EXAMPLE 3
Preparation of Non-Dispersive TTCP/DCPA-Based CPC Powder (Abbreviated as ND-CPC)
[0072] The TTCP powder prepared according to the method of PREPARATIVE EXAMPLE 1 was sieved and blended with dried CaHPO 4 (DCPA) powder in a ball mill for 12 hours. The blending ratio of the TTCP powder to the DCPA powder was 1:1 (molar ratio). The resultant powder mixture was added to a 25 mM diluted solution of phosphate to obtain a powder/solution mixture having a concentration of 3 g powder mixture per 1 ml solution while stirring. The resulting powder/solution mixture was formed into pellets, and the pellets were heated in an oven at 50° C. for 10 minutes. The pellets were then uniformly ground in a mechanical mill for 20 minutes to obtain the non-dispersive TTCP/DCPA-based CPC powder (ND-CPC). The particles of this ND-CPC powder have whisker on the surfaces thereof.
[0000] Dense blocks
EXAMPLE 1
Effect of Immersion Time on Compressive Strength of CPC Block
[0073] To a setting solution of IM phosphoric acid solution (pH=5.89) the ND-CPC powder from PREPARATIVE EXAMPLE 3 was added in a liquid/powder ratio (L/P ratio) of 0.4, i.e. 4 ml liquid/10 g powder, while stirring. The resulting paste was filled into a cylindrical steel mold having a length of 12 mm and a diameter of 6 mm, and was compressed with a gradually increased pressure until a maximum pressure was reached. The maximum pressure was maintained for one minute, and then the compressed CPC block was removed from the mold. At the 15 th minute following the mixing of the liquid and powder, the compressed CPC block was immersed in a Hanks' solution for 1 day, 4 days, and 16 days. Each test group of the three different periods of immersion time has five specimens, the compressive strength of which was measured by using a AGS-500D mechanical tester (Shimadzu Co., Ltd., Kyoto, Japan) immediately following the removal thereof from the Hanks' solution without drying. The CPC paste in the mold was compressed with a maximum pressure of 166.6 MPa, and in the course of the compression the compression speeds were about 5 mm/min during 0˜104.1 MPa; 3 mm/min during 104.1˜138.8 MPa; 1 mm/min during 138.8˜159.6 MPa: and 0.5 mm/min during 159.6˜166.6 MPa. The measured wet specimen compressive strength is listed Table 1.
TABLE 1 Compressive Immersion time (Day) strength (MPa) Standard deviation (MPa) No immersion 37.3* 0.6 1 day 149.2 12.9 4 days 122.7 6.7 16 days 116.4 7.7 *This value was measured before the compressed CPC blocks were immersed in the Hanks' solution, and it was substantially the same for the compressed CPC blocks not immersed in the Hanks' solution measured a few days after the preparation.
[0074] It can seen from Table 1 that the compressive strength of the compressed CPC blocks is increased remarkably after one-day immersion in comparison with the non-immersed block, and declines a little for a longer immersion time.
EXAMPLE 2
Effect of Whiskers on Compressive Strength of TTCP/DCPA-Based CPC Block
[0075] The procedures of EXAMPLE 1 were repeated by using the C—CPC powder prepared in PREPARATIVE EXAMPLE 2 and the ND-CPC powder prepared in PREPARATIVE EXAMPLE 3. The maximum pressure used to compress the CPC paste in the mold in this example was 156.2 MPa. The results for one-day immersion time are listed in Table 2.
TABLE 2 Compressive Standard CPC powder strength (MPa) deviation (MPa) C-CPC (no whisker) 62.3 5.0 ND-CPC (with whisker) 138.0 8.2
[0076] It can be seen from Table 2 that the compressive strength, 62.3 MPa, of the immersed compressed CPC block prepared from the conventional CPC powder (no whisker) is about 1.7 times of that (37.3 MPa) of the non-immersed compressed CPC block in Table 1, and the compressive strength, 138.0 MPa, of the immersed compressed CPC block prepared from the non-dispersive CPC powder (with whisker) is about 3.7 times of that of the non-immersed compressed CPC block in Table 1
EXAMPLE 3
Effect of Whiskers on Compressive Strength of TTCP-Based CPC Block
[0077] Ca 4 (PO 4 ) 2 O (TTCP) powder as synthesized in PREPARATIVE EXAMPLE 1 was sieved with a #325 mesh. The sieved powder has an average particle size of about 10 μm. To the TTCP powder HCl aqueous solution (pH=0.8) was added according to the ratio of 1 g TTCP/13 ml solution. The TTCP powder was immersed in the HCl aqueous solution for 12 hours, filtered rapidly and washed with deionized water, and filtered rapidly with a vacuum pump again. The resulting powder cake was dried in an oven at 50° C. The dried powder was divided into halves, ground for 20 minutes and 120 minutes separately, and combined to obtain the non-dispersive TTCP-based CPC powder, the particles of which have whisker on the surfaces thereof. A setting solution of diammonium hydrogen phosphate was prepared by dissolving 20 g of diammonium hydrogen phosphate, (NH 4 ) 2 HPO 4 , in 40 ml deionized water. The procedures in EXAMPLE 1 were used to obtain the wet specimen compressive strength for one-day immersion time, wherein the maximum pressure to compress the CPC paste in the mold was 156.2 MPa. The results are shown in Table 3.
TABLE 3 Compressive Standard CPC powder strength (MPa) deviation (MPa) TTCP (no whisker) 79.6 8.8 TTCP (with whisker) 100 4.2
[0078] The trend same as the TTCP/DCPA-based CPC powder in Table 2 of EXAMPLE 2 can be observed in Table 3.
EXAMPLE 4
Effect of Molding Pressure on Compressive Strength of ND-CPC Block (in Low Pressure Regime: 0.09˜3.5 MPa)
[0079] The procedures of EXAMPLE 1 were repeated except that the maximum pressure used to compress the CPC paste in the mold was changed from 166.6 MPa to the values listed in Table 4. The period of immersion was one day. The results are listed in Table 4.
TABLE 4 Pressure for compressing the CPC paste in mold Compressive Standard (MPa) strength (MPa) deviation (MPa) 0.09 12.3 2.0 0.35 16.0 2.3 0.7 20.7 2.5 1.4 26.4 1.4 3.5 35.2 3.7
[0080] The data in Table 4 indicate that the compressive strength of the CPC block increases as the pressure used to compress the CPC paste in the mold increases.
EXAMPLE 5
Effect of Reducing Liquid/Powder Ratio During Compression of the CPC Paste in the Mold on Compressive Strength of ND-CPC Block
[0081] The procedures of EXAMPLE 1 were repeated except that the maximum pressure used to compress the CPC paste in the mold was changed from 166.6 MPa to the values listed in Table 5. The liquid leaked from the mold during compression was measured, and the liquid/powder ratio was re-calculated as shown in Table 5. The period of immersion was one day. The results are listed in Table 5.
TABLE 5 Pressure for compressing the L/P ratio (after Compressive Standard CPC paste in a portion of strength deviation mold (MPa) liquid removed) (MPa) (MPa) 1.4 0.25 26.4 1.4 34.7 0.185 75.3 3.9 69.4 0.172 100.4 6.8 156.2 0.161 138.0 8.2 166.6 0.141 149.2 12.9
[0082] The data in Table 5 show that the compressive strength of the CPC block increases as the liquid/powder ratio decreases during molding.
EXAMPLE 6
Effect of Post-Heat Treatment on Compressive Strength of CPC Block
[0083] The procedures of EXAMPLE 1 were repeated. The period of immersion was one day. The CPC blocks after removing from the Hanks' solution were subjected to post-heat treatments: 1) 50° C. for one day; and 2) 400° C. for two hours with a heating rate of 10° C. per minute. The results are listed in Table 6.
TABLE 6 Compressive Standard strength (MPa) deviation (Mpa) No post-heat treatment 149.2 12.9 50° C., one day 219.4 16.0 400° C., two hours 256.7 16.2
[0084] It can be seen from Table 6 that the post-heat treatment enhances the compressive strength of the CPC block.
[0000] Porous Blocks
EXAMPLE 7
Effect of KCl Content and Immersion Time on Compressive Strength of Porous CPC Block
[0085] To a setting solution of IM phosphoric acid solution (pH=5.89) the ND-CPC powder from PREPARATIVE EXAMPLE 3 was added in a liquid/powder ratio (L/P ratio) of 0.4, i.e. 4 ml liquid/10 g powder, while stirring. KCl powder in a predetermined amount was mixed to the resulting mixture by stirring intensively. The resulting paste was filled into a cylindrical steel mold having a length of 12 mm and a diameter of 6 mm, and was compressed with a gradually increased pressure until a maximum pressure of 3.5 MPa was reached. The maximum pressure was maintained for one minute, and then the compressed CPC block was removed from the mold. At the 15 th minute following the mixing of the liquid and powders, the compressed CPC block was immersed in a deionized water at 37° C. for 4 days, 8 days, and 16 days. The compressive strength of the specimens of the three different periods of immersion time was measured by using a AGS-500D mechanical tester (Shimadzu Co., Ltd., Kyoto, Japan) after the specimens were dry. The measured dry specimen compressive strength is listed Table 7.
TABLE 7 Dry compressive strength (MPa) Immersion time (Day) KCl/CPC ratio by weight 4 days 8 days 16 days 1 7.0 5.4 6.6 1.5 3.9 2.7 4.3 2 1.3 2.3 2.6
[0086] It can seen from Table 7 that the dry compressive strength of the porous CPC blocks decreases as the KCl/CPC ratio by weight increases.
EXAMPLE 8
Porosity and Compressive Strength of Porous CPC Blocks Prepared From Different Pore-Forming Powders
[0087] The procedures of EXAMPLE 7 were repeated by using sugar, K 1 , C 17 H 33 COONa and C 13 H 27 COOH instead of KCl. The immersion time was 14 days in deionized water. In the cases where the C 17 H 33 COONa and C 13 H 27 COOH were used, the CPC blocks were further immersed in ethanol for additional four days. The conditions and the results are listed in Table 8.
TABLE 8 Pore-forming powder S a) C.S. (MPa) b) Porosity (vol %) c) Sugar 1 4.1 58.4 KI 2 4.3 62.2 KI 3 1.7 75.5 C17H33COONa 1 8.0 56.0 C13H27COOH 2 5.9 60.1 a) S = Pore-forming powder/CPC by volume. b) C.S. = dry compressive strength (hereinafter abbreviated as C.S.). c) Porosity: Porosity (vol %) was measured by Archimedes' method, and calculated as in ASTM C830.
[0088] It can be seen from Table 8 that various powders which are soluble in water can be used in the preparation of a porous CPC block according to the method of the present invention.
[0000] Dual-Functional Block
EXAMPLE 9
[0089] To a setting solution of IM phosphoric acid solution (pH=5.89) the ND-CPC powder from PREPARATIVE EXAMPLE 3 was added in a liquid/powder ratio (L/P ratio) of 0.4, i.e. 4 ml liquid/10 g powder, while stirring. KCl powder in a ratio of KCl powder/CPC by volume of 2 was mixed to the resulting mixture by stirring intensively. The resulting paste was filled into a cylindrical steel mold having a length of 12 mm and a diameter of 7 mm, and was compressed with a gradually increased pressure until a maximum pressure of 3.5 MPa was reached. The maximum pressure was maintained for one minute, and then the compressed CPC block was removed from the mold at the 15 th minute following the mixing of the liquid and powders.
[0090] The resulting cylinder having a diameter of 7 mm was placed in another cylindrical steel mold having a diameter of 10 mm. To a setting solution of IM phosphoric acid solution (pH=5.89) the ND-CPC powder from PREPARATIVE EXAMPLE 3 was added in a liquid/powder ratio (L/P ratio) of 0.4, i.e. 4 ml liquid/10 g powder, while stirring. The resulting paste was filled into the gap between said cylinder and said another mold, and was compressed with a gradually increased pressure until a maximum pressure of 50 MPa was reached. The maximum pressure was maintained for one minute. At the 15 th minute following the mixing of the liquid and ND-CPC powder, the CPC/KCl composite block was immersed in a deionized water at 37° C. for 4 days. KCl powder was dissolved in the deionized water, and a dual-functional CPC block having a porous CPC cylinder surround by a dense CPC annular block was obtained.
[0091] The compressive strength of the specimen was measured by using a AGS-500D mechanical tester (Shimadzu Co., Ltd., Kyoto, Japan) after the specimens were dry. The measured dry specimen compressive strength is 68.8 MPa.
[0092] The porosities of the porous CPC cylinder and the dense CPC annular block were measured by Archimedes' method, and calculated as in ASTM C830, after the dual-functional CPC block was broken intentionally, and the results are 74% and 30%, respectively.
[0093] X-ray diffraction pattern of the powder obtained by grinding the dual-functional CPC block shows broadened characteristic X-ray diffraction peaks of apatite at 2θ=25-27° and 2θ=20-35° w ith a scanning range of 2θ of 20-40° and a scanning rate of 10/min. The results indicate that the powder is a mixture of apatite and TTCP with apatite as a major portion. | The present invention discloses a prosthetic bone implant made of a hardened calcium phosphate cement having an apatitic phase as a major phase, which includes a dense cortical portion bearing the majority of load and a porous cancellous portion allowing a rapid blood/body fluid penetration and tissue ingrowth. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to array cells and more particularly, the invention relates to circuitry for a CMOS array cell and a method for utilizing the circuitry for programming and erasing the cell.
2. Description of the Related Art
Typically in current technology, CMOS array cells for programmable logic devices (PLDs) are programmed and erased using Fowler-Nordheim tunneling (FNT) or channel hot carrier injection. A typical cell using FNT is depicted in FIG. 1. A CMOS inverter is formed with an NMOS transistor 10 and a PMOS transistor 12 with a merged floating gate 14. A capacitor 16 is coupled to the merged floating gate to form the array control gate (ACG) 18. A tunnel capacitor 20 is provided to charge and discharge the merged floating gate 14. A write signal applied to the gate 22 of pass transistor 24 controls programming and erasing of the floating gate 14 via the tunnel capacitor 20.
To program the cell of FIG. 1 (i.e., to add holes to the floating gate), the word control line 26 is raised to V pp (typically 12 v) and a voltage higher than V pp (typically 14 v) is applied to the gate 22 of pass transistor 24, turning "on" pass transistor 24. ACG 18, V ssp 28, and V ssn 30 are brought to ground. Electrons will then migrate off the floating gate 14 through the tunnel capacitor 20.
To erase the same array cell (i.e., add electrons to the floating gate), word control line 26 is brought to ground, and V cc (typically 5 V) is applied to gate 22 of pass transistor 24. ACG 18, V ssp 28, and V ssn 30 will be raised to V pp . Electrons will thus migrate onto the floating gate 14 through tunnel capacitor 20.
While FNT is popular, it requires high voltages and causes damage to tunneling oxide layers through which electrons travel during program or erase. Further, if pass transistor 24 is not used, the cell is essentially a two-terminal device (i.e., only V pp and GND), which requires that all cells in an array be programmed or erased at the same time.
Channel hot electron (CHE) injection is depicted in FIG. 2. A single NMOS transistor 50 is shown. Transistor 50 has a floating gate 52 and a control gate 54, as well as a drain 58, a source 60 and a substrate 62. For CHE injection a potential difference is created between the drain 58 and the source 60 by applying, for instance, 6 volts to the drain 58 and grounding the source 60. A potential difference is also created between the drain 58 and the control gate 54, by, for instance, applying an additional voltage of 9 volts to the control gate 54 while grounding the substrate 62. A current will then flow in the channel region 56 between the source 60 and drain 58 creating a pinchoff region in the channel by applying the source to drain voltage difference. With the gate voltage further applied, electrons in the channel region 56 gain energy from the electric fields created and can then surmount the energy barrier (approx. 3.1 eV) existing at the substrate surface 64 and cross from the channel region 56 to the oxide layer 66 at the pinchoff region. Once in the oxide layer 66, the electrons are pulled to the floating gate 52, driven by the potential difference electric field across the oxide layer 66. Channel hot hole (CHH) injection is accomplished in a similar manner on a PMOS device.
While channel hot carrier injection is advantageous in the respect that it utilizes three terminals, allowing individual cells to be erased or programmed at a given time, channel hot carrier injection generates a high current (approximately 1 mA) on the source-drain current path, which is not desirable for maintaining a low power device.
SUMMARY OF THE INVENTION
The present invention utilizes lower voltages during program and erase than Fowler-Nordheim tunneling, as well as lower current than channel hot carrier injection, resulting in a low power array cell.
Further, during program and erase, the present invention provides an array cell utilizing three terminals, thus, individual cells may be selected and isolated for programming or erasing.
In an embodiment, the present invention further utilizes a CMOS cell so that zero power is consumed during a read operation.
The present invention is an array cell comprising a first transistor, having a floating gate and a source-drain current path, and a second programmable and erasable transistor, having a floating gate and a source-drain current path. The source-drain current path of the second transistor is coupled to the source-drain path of the first transistor. The floating gate of the first transistor may be merged with the floating gate of the second transistor. Further, the second transistor is programmed and erased using avalanche hot carrier injection at a p-n junction of the second transistor. In addition, a depletion transistor having a gate connected to its source has a source-drain path supplying current to the second transistor of the array cell to limit current during avalanche injection.
BRIEF DESCRIPTION OF THE DRAWINGS
Further details of the present invention are explained with the help of the attached drawings in which:
FIG. 1 is a schematic diagram illustrating a memory cell utilizing Fowler-Nordheim tunneling;
FIG. 2 is a partial, cross-sectional view of a transistor in a memory cell utilizing channel hot electron erase;
FIG. 3 is a schematic diagram of a CMOS array cell;
FIG. 4 is a partial, cross-sectional view of part of the array cell shown in FIG. 3, utilizing avalanche hot carrier injection;
FIG. 5 is a graphical representation of a substrate current versus the voltage applied to an array cell during program and erase;
FIG. 6 is a schematic representation of one embodiment of the present invention;
FIG. 7 is a schematic representation of a second embodiment of the present invention;
FIG. 8 is a schematic representation of a third embodiment of the present invention; and
FIG. 9 is a partial, cross-sectional representation of a constructional model of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is a CMOS array cell configured to be programmed and erased utilizing controlled avalanche hot carrier injection. FIG. 3 shows an array cell formed by a CMOS inverter with a PMOS transistor 102 and an NMOS transistor 104. Drain 108 of transistor 102 is connected to drain 122 of transistor 104. The floating gates 107 and 117 of the respective transistors are merged to form merged floating gate 118. A capacitor 120 is coupled to the merged floating gate 118 to form the array control gate (ACG) 121.
It is desirable to use avalanche hot carrier injection to program and erase the cell of FIG. 3 as it will yield a lower power operation than other methods. Avalanche hot electron (AHE) injection is used to erase the array cell 100 by causing an avalanche breakdown in transistor 104, and is illustrated in FIG. 4. With AHE injection, no source-drain current is created. Rather, a high reverse-bias at p-n junction 123 is created by applying a high drain 122 to substrate 112 potential. (Source 116 may remain floating.) When the junction is reverse-biased and the oxide field is positive (i.e., gate potential is higher than the substrate), avalanche breakdown will occur, causing electrons generated at the p-n junction 123 to "inject" to the floating gate 118, thus erasing the cell 100. Similarly, if the oxide field is negative (i.e., the gate potential is lower than the substrate) holes generated at the p-n junction 123, rather than in the channel as in CHH injection, will inject to the floating gate 118, thus programming the cell 100 using avalanche hot hole (AHH) injection.
Although avalanche hot carrier injection uses lower voltages than other methods, one problem with using avalanche hot carrier injection is that a high substrate current (I sub ) may result. FIG. 5 shows a characteristic substrate current versus V ssp (the voltage applied at the drain 122 of transistor 104) applied for a particular cell during avalanche hot carrier injection. As shown by curve 150, breakdown occurs at a particular voltage V BD , and current substantially increases when even slightly higher voltages are applied. Such a high I sub is undesirable as it will demand all of the current from the current supply (i.e., a charge pump), making it impossible for other cells to reach breakdown (as they will be deprived of current), and thus to be erased or programmed. In other words, only the cell at the lowest breakdown voltage will have sufficient current to be erased or programmed. Therefore, while it is desirable to use avalanche hot carrier injection for programming and erasing, breakdown current must be controlled.
One embodiment of the present invention is depicted in FIG. 6. Array cell 300 is composed of transistor 302, transistor 304, and transistor 324. Transistor 302 has a source 306, a drain 308 and a floating gate 307. The substrate 310 of transistor 302 is connected to the source 306 of transistor 302. Transistor 302 typically acts as a switchable current source, allowing current to pass from its source 306 to its drain 308 (in a source-drain current path) when the voltage applied between gate 307 and V ssp reaches a particular threshold voltage.
Transistor 304 has a source 316, a drain 322 and a floating gate 317. The substrate 312 of transistor 304 is connected to ground 314. Transistor 304 is the transistor utilized particularly for programming and erasing the cell using avalanche hot carrier injection.
Further, floating gates 307 and 317 are merged to form a single merged floating gate 318. A capacitor 320 is coupled to the merged floating gate 318 to form the array control gate (ACG) 321.
A third transistor 324 is coupled to the source-drain paths of transistor 302 and transistor 304. In the embodiment shown in FIG. 6, this coupling includes drain 328 of transistor 324 coupled to drain 308 of transistor 302, and source 326 of transistor 324 coupled to drain 322 of transistor 304.
A reference voltage generator 332 is coupled to gate 330 of transistor 324. Reference voltage generator 332 provides a reference voltage V ref to the gate 330 of transistor 324. By adjusting the reference voltage to the gate 330 of transistor 324, current flowing through the source-drain path of transistor 324 can essentially be regulated. Thus, during a program or erase function, current will be able to flow from the source-drain path of transistor 302 through the source-drain path of transistor 324 to transistor 304. However, by adjusting V ref , the amount of current that reaches transistor 304 may be varied such that current does not significantly increase after breakdown occurs as shown by line 150 in FIG. 5, and, thus, current may be regulated.
While applying a voltage at gate 330 of transistor 324 will regulate the current through the source-drain path of transistor 324, the solution of FIG. 6 may require significant additional circuitry to generate a reference voltage. Therefore, another embodiment of the present invention creates a solution to the high breakdown current problem by providing a reference voltage with minimal additional circuitry. In FIG. 7 the circuitry is similar to that described in FIG. 6 with the exception that gate 330 of transistor 324 is connected to the source 326 of transistor 324 and also to the drain 322 of transistor 304. Further, transistor 324 is an n-type depletion MOS transistor, meaning that transistor 324 is ion implanted with an n-doped material 333, such as arsenic (As), which causes the threshold, V th , of transistor 324 to become approximately -1v (non-depletion NMOS transistors, or "enhancement" NMOS transistors, typically have a V th near 0.8v). Thus, even if the voltage at the gate of transistor 324 is 0 v, transistor 324 may still be "on" (current may flow in its source-drain current path).
During program and erase functions, current will flow from transistor 302 to transistor 304. In this manner transistor 324 will always be turned "on" (the condition for turning on the transistor, V gate -V th >V source , will always be true), and the voltage resulting at drain 322 of transistor 304 will be held relatively constant. Thus, transistor 324 acts like a "smart" resistor, automatically limiting the current that passes through it without having to independently evaluate and adjust V ref . The voltage at drain 322 of transistor 304 will be held near its breakdown voltage (approximately 8v) and in this manner, substrate current can be held to between approximately 1 and 10 μA. FIG. 5 graphically illustrates a characteristic curve for substrate current versus V ssp . Characteristic curve 152 depicts how current will be limited as V ssp is raised above breakdown voltage (V BD ).
FIG. 8 depicts yet another embodiment of the invention, and is similar to the embodiment described in FIG. 7, except gate 330 of transistor 324 is coupled to the drain 328 of transistor 324. This embodiment also provides current control as shown in FIG. 5 at curve 154.
FIG. 9 is a partial cross-sectional constructional diagram of the present invention. Transistor 302 is composed of an N + -doped well 602; two P + -doped wells 604, as well as two p - spacers 606. Transistor 324 is set on a P-substrate 610 and is composed of N + wells 612 as well as n- spacers 613. Transistor 324 also has an ion implanted region 614, typically implanted with an n-type material, which may be arsenic (As). Transistor 304 is set on P-substrate 610, and has N + wells 612. However, transistor 304 contains no spacer (i.e., no n - /p - doping). Lack of such a spacer reduces the breakdown voltage required to reach avalanche conditions, thus making this array cell a low power device during program and erase.
In operation to erase the array cell 300 shown in FIGS. 7 and 8 using AHE injection, (i.e., to add electrons to the floating gate 318) a voltage, typically between 7 and 12 volts, preferably 10 volts, should be applied to source 306 of transistor 302. A voltage equal to or higher should be applied to the ACG 321, preferably 10 to 11 volts. Best operation has been found when the source 316 is left floating, although grounding source 316 may also work. Substrate 312 of transistor 304 should be brought to a voltage substantially lower than that applied to ACG 321, preferably ground. With the above voltages applied, the p-n junction 616 (shown in FIG. 9) becomes reverse-biased, and electrons will "inject" onto the floating gate through the p-n junction.
To program array cell 300, using AHH injection (i.e., to add holes to the floating gate 318) a voltage, typically 7 to 12 volts, and preferably 10 volts, should be applied to source 306 of transistor 302. Source 316 of transistor 304, like above, is best left floating. Substrate 312 of transistor 304 should also be brought to a relatively low voltage, preferably ground. ACG 321, however, should also be brought to a relatively low voltage, similar to substrate 312, and preferably ground. Similar to erasing, the p-n junction 616 (shown in FIG. 9) becomes reverse-biased, and holes generated at the p-n junction will "inject" to the floating gate.
By using a CMOS cell structure, the present invention consumes low power during read. For examples referring to FIGS. 7 and 8, during a read operation, source 306 of transistor 302 (V ssp ) will typically be held at voltage V cc , the ACG voltage will be held at 1/2 V cc and the source 316 of transistor 304 (V ssn ) will typically be held to ground. It is further assumed that in a non-programmed and non-erased state the threshold of transistors 302 and 304 are 1/2 V cc . If the floating gate 318 is then programmed (positively charged), during read transistor 304 will be turned "on" and transistor 302 will be turned "off", causing the output to go to a "low" state. Alternatively, if the floating gate is erased (negatively charged) the n-type transistor 304 is turned off, the p-type transistor 302 is turned on, and the output is "high." In either case, current has no path from V cc to ground, thus little to no power will be drawn. Note that other voltages may be applied in place of V cc and the ACG voltage, and particular threshold conditions of transistors 302 and 304 may be set as indicated in U.S. patent application Ser. No. 08/426,741 entitled "Reference For CMOS Memory Cell Having PMOS and NMOS Transistors With a Common Floating Gate" which is incorporated herein by reference.
It should be understood that the particular embodiments described above are only illustrative of the principles of the present invention, and various modifications could be made by those skilled in the art without departing from the scope and spirit of the present invention. For instance, p-type transistors or n-type transistors could be substituted for transistors of the opposite type. Further, all n-type or all p-type transistors could be used, although this may sacrifice zero power operation during read. In addition, while the invention has been described in the context of an array, it is to be understood that such an array could be composed of a single stand-alone cell. Thus, the scope of the present invention is limited only by the claims that follow. | A low power CMOS array cell for use in a PLD device is disclosed. The cell utilizes controlled avalanche injection at the p-n junction of a transistor in the CMOS cell for programming and erasing, resulting in lower voltages than with Fowler-Nordheim tunneling and lower currents than channel hot carrier injection during program and erase. A depletion transistor having a gate connected to its source has a source-drain path supplying current to the CMOS cell to limit current required during avalanche injection. | 6 |
FIELD OF INVENTION
The present invention relates to the field of beverage bottles and fluid receptacles, and more specifically to a beverage cooler which has improved cooling efficiency and functionality over standard bottle storage and cooling devices.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a illustrates a side perspective view of one embodiment of a geometrically optimized beverage cooler with uniform size support contours for similar sized beverages.
FIG. 1 b illustrates a side perspective view of one embodiment of a geometrically optimized beverage cooler with non-uniform size support contours for beverages of varying sizes.
FIG. 1 c illustrates an exploded view of two geometrically optimized beverage coolers stacked.
FIG. 1 d illustrates a side perspective view of a second embodiment of a geometrically optimized beverage cooler.
FIG. 2 a illustrates a top view of one embodiment of a geometrically optimized beverage cooler.
FIG. 2 b illustrates a bottom view of one embodiment of a geometrically optimized beverage cooler.
FIG. 3 a illustrates a sectional view of one embodiment of a geometrically optimized beverage cooler.
FIG. 3 b illustrates a sectional view of an alternate embodiment of a geometrically optimized beverage cooler.
FIG. 4 a illustrates a top view of one embodiment of a lid for a geometrically optimized beverage cooler.
FIG. 4 b illustrates a sectional view of one embodiment of a lid for a geometrically optimized beverage cooler.
FIG. 4 c illustrates an exploded view of one embodiment of a geometrically optimized beverage cooler with lid.
FIG. 5 illustrates a side perspective view of one embodiment of a geometrically optimized beverage cooler with optional drip pan.
GLOSSARY
As used herein, the term “cooler” refers to any apparatus, container or receptacle for holding ice and cooling materials.
As used herein, the term “beverage container” refers to any fluid-filled container such as a bottle, can, carafe, vial or syringe, and is not limited to containers in which the beverage is a fluid.
As used herein, the term “angled surface” or “angled bottom surface” means angled relative to at least one horizontal and at least one perpendicular surface. An angled surface may include, but is not limited to a dome shape or a solid curved structure and may be comprised of one or more segments or angled structures.
As used herein, the term “perimeter ridge” refers to a raised edge of an object.
As used herein, the term “flattened perimeter area” refers to a level portion of a component which rests on a surface (e.g., table).
As used herein, the term “integrally constructed” means formed or created as a single piece or complete unit.
As used herein, the term “friction resistant structures” refers to a structural component including, but not limited to grooves, protuberances, contour, or deformations that reduces the resistance of one component against another.
As used herein, the term “fluted” means having at least one groove or furrow.
BACKGROUND
Consumers spend billions of dollars on bottled and canned beverages each year. The market for beer alone is in excess of $100 billion dollars, and more than 40 billion dollars of bottled water is sold year. Bottles may be made of glass, plastic or other materials. Cans are made of a variety of recyclable metals.
Most beverages are consumed in social settings, such as parties, bars, restaurants, and other events.
Beverage coolers (including chests, buckets, pails and other storage devices) are generally used by consumers to store and serve bottled beverages in settings where ice, rather than standard refrigeration, must be used to cool bottled and canned beverages. Chests are desirable because they hold a quantity of beverages and may be insulated or constructed to serve as portable refrigerators. Buckets (e.g., champagne buckets) may be ornamental or easy to transport. They are generally constructed with handles and prevent leaking of melting ice.
Coolers made of Styrofoam™ or other inexpensive materials are frequently sold at the point-of-purchase for these beverages. Additionally, beer and wine cooling devices are sold at retail outlets and command considerable shelf space in seasonal and non-seasonal markets. Coolers are profitable items for which competition is intense. For example, Walmart™ alone carries several dozen coolers in its stores simultaneously.
The cost of coolers and beer buckets can range from a few dollars to more than $80.00 to $100.00. Generally, Styrofoam™ containers dominate the low cost market and are sold at point-of-purchase. In addition, they are lightweight and stackable.
However, Styrofoam™ is environmentally hazardous, flakes easily and is unattractive to display. Styrofoam® is also not a material which is attractive for consumers to re-use and Styrofoam™ coolers are discarded at a high rate because of these issues, resulting in a short useful life.
Cooler and bucket devices known in the art also take up storage space, making it impractical to keep a number of devices on hand for occasional use (e.g., for parties, picnics or barbeques). Collapsible coolers directed at this problem are known in the art, but are cumbersome and often prone to mildew because they have numerous crevices.
In addition, the rectangular and/or rounded design of traditional coolers and buckets is not adapted for retail sale environments or for consumers who have not previously intended to purchase a cooler. Traditional chest-type coolers and buckets lack the visual appeal necessary for consumers to consider them as a point-of-purchase item (e.g., displayed near a register with limited counter space).
Additionally, the market is relatively untapped for consumers who want small receptacles for cooling and transporting beverages in the most popularly sold quantities: 6 packs, 12 packs, 24 packs and 30 packs.
Users of traditional coolers and buckets also need to manually push aside wet ice cubes to find a bottle. When multiple types of beverages are stored in a cooler, a user must lift the bottles out of the cooler in order to read the label.
It is desirable to have a device which makes beverages visible for selection based on a user's preference and easy for a user to grasp without the need for the user to grope through ice and cold water.
Little attention has been given to optimizing the geometric configuration of coolers and buckets so that less ice may be used, cooling efficiency may be optimized, and the weight of transporting the apparatus may be reduced.
Traditional coolers and buckets are not adapted for display and use on tables, buffets, and at other events, and their design does not encourage consumers to re-use them. Coolers and buckets look out of place on serving tables, rather than blend into the serving décor.
SUMMARY OF THE INVENTION
The present invention is a geometrically optimized beverage cooler, which positions fluid-filled containers (bottles, cans, vials, syringes, etc.) in an angled, upright, and evenly spaced position for serving and display. The device uniformly distributes ice and cold water around each bottle to maximize the effective cooling capacity of a given quantity of ice, thus reducing the amount of ice needed and the weight of the device during transport. Various embodiments of the apparatus include an ergonomically and structurally reinforced handle and an insulating lid having complementary contours.
DETAILED DESCRIPTION OF INVENTION
For the purpose of promoting an understanding of the present invention, references are made in the text to exemplary embodiments of a geometrically optimized beverage cooler, only some of which are described herein. It should be understood that no limitations on the scope of the invention are intended by describing these exemplary embodiments. One of ordinary skill in the art will readily appreciate that alternate but functionally equivalent materials, sizes, shapes and designs may be used. The inclusion of additional elements may be deemed readily apparent and obvious to one of ordinary skill in the art. Specific elements disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one of ordinary skill in the art to employ the present invention.
It should be understood that the drawings are not necessarily to scale; instead, emphasis has been placed upon illustrating the principles of the invention. In addition, in the embodiments depicted herein, like reference numerals in the various drawings refer to identical or near identical structural elements.
Moreover, the terms “substantially” or “approximately” as used herein may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related.
FIG. 1 a illustrates a side perspective view of one embodiment of a highly efficient geometrically optimized cooler 100 having cooler body 10 and uniform size support contours 20 a , 20 b , 20 c , 20 d , 20 e and 20 f which are evenly spaced to partially encase and support uniform size bottle structures at an angle of 90 to 150 degrees. The slope of angled bottom 50 (not shown) directs the angle at which the bottles are positioned when placed in geometrically optimized cooler 100 .
In other embodiments, support contours 20 a , 20 b , 20 c , 20 d , 20 e and 20 f may be adapted to encase fewer other types of fluid-filled containers such as cans, vials, carafes, glasses and syringes. Geometrically optimized cooler 100 may include more or fewer support contours 20 a , 20 b , 20 c , 20 d , 20 e and 20 f , and in other embodiments, support contours 20 a , 20 b , 20 c , 20 d , 20 e and 20 f may not be uniform to accommodate various sizes of fluid-filled containers. In still other embodiments, support contours 20 a , 20 b , 20 c , 20 d , 20 e and 20 f may not be symmetrical or evenly spaced.
Also visible in FIG. 1 is center column 30 which includes handle 40 . In various embodiments, center column 30 may be hollow, solid, cylindrical, angled, tapered, or have any other shape, size or proportions. In the embodiment shown, center column 30 is tapered and hollow allowing for stacking.
In the embodiment shown, geometrically optimized cooler 100 , center column 30 , and handle 40 are a singly molded component formed from an injection molding process. In other embodiments, geometrically optimized cooler 100 may be constructed of multiple components (e.g., a separately formed handle or insulating layer). In various embodiments, handle 40 may be rigid, semi-rigid or flexible.
In the embodiment shown, geometrically optimized cooler 100 is comprised of polyethylene plastic, but in other embodiments may be comprised of another type of plastic or materials having the following qualities: resistance to ultraviolet rays, ability to function under temperature variations, fluid impermeable, light weight and low cost. In various embodiments, geometrically optimized cooler 100 may be of any size or proportions.
FIG. 1 b illustrates a side perspective view of one embodiment of geometrically optimized beverage cooler 100 with support contours 20 a , 20 b , 20 c , 20 d , 20 e and 20 f of non-uniform sizes to accommodate beverage containers of varying sizes. In the embodiment shown, cooler body 10 further includes structural supporting perimeter ridge 12 , which prevents cooler from being deformed and provides structural support/integrity for cooler body 10 and support contours 20 a , 20 b , 20 c , 20 d , 20 e and 20 f by strengthening and adding rigidity.
FIG. 1 c illustrates an exploded view of two geometrically optimized coolers 100 a and 100 b illustrating their capability of being stacked.
FIG. 1 d illustrates a side perspective view of a second embodiment of geometrically optimized cooler 100 which has a larger area for holding fluid-filled containers and includes additional handles for carrying geometrically optimized cooler 100 .
FIG. 2 a illustrates a top view of highly efficient geometrically optimized cooler 100 illustrating angled bottom 50 , which is a contoured bottom surface which supports bottles or other containers placed in geometrically optimized cooler 100 . Angled bottom 50 forces bottles, cans or other fluid-filled containers to tilt outward against the inner surface of cooler body 10 and within support contours 20 a , 20 b , 20 c , 20 d , 20 e and 20 f.
Also visible in FIG. 2 a is handle 40 , which in the embodiment shown, is a flattened handle with a structural ridge along the perimeter for structural reinforcement and strength. In other embodiments, handle 40 may be curved, contoured to receive one or more fingers, or otherwise altered or enhanced without departing from the functionality of a handle. In still other embodiments, handle 40 may be constructed from different or additional components than that of cooler body 10 .
FIG. 2 b illustrates a bottom view of highly efficient geometrically optimized cooler 100 , further illustrating angled bottom 50 . In the embodiment shown, geometrically optimized cooler 100 has flattened perimeter area 45 which ensures that geometrically optimized cooler 100 remains level. In other embodiments, flattened perimeter area 45 may have a larger number of contact points (e.g., may have three separate contact points).
FIG. 3 a illustrates a sectional view of highly efficient geometrically optimized cooler 100 . Visible in FIG. 3 a are cooler body 10 , center column 30 , lid 80 , and handle 40 . In various embodiments, center column 30 may be tapered, hollow, or solid. Also visible in FIG. 3 a is structural and reinforcing handle rib 42 .
In the embodiment shown, cooler body 10 of geometrically optimized cooler 100 is comprised of a single layer 70 ; however, in other embodiments may be comprised of additional layers such as decorative material, insulating material or strengthening material. Cooler body 10 may have additional ribs, supports or structural contours, and may include apertures for inserting handles or for drainage.
FIG. 3 a also illustrates friction resistant structures 77 a and 77 b ( 77 b not visible), which are on the inner surface of center column 30 and prevent center columns 30 from adhering together when stacked. In various embodiments, friction resistant structures 77 a and 77 b may be grooves or protuberances or any other friction resisting contours or deformations.
FIG. 3 b illustrates a sectional view of an alternate embodiment of geometrically optimized cooler 100 , which includes optional insulating layer 75 which may be foam, rubber or any other insulating material or coating known in the art. Other embodiments may include optional outer layers (not shown), including ornamentation such as paint, decals, fabric, or any other material capable of being formed into an outer layer.
FIG. 4 a illustrates a top view of one embodiment of lid 80 for geometrically optimized cooler 100 . In the embodiment shown, lid 80 has lid contours 87 a , 87 b , 87 c , 87 d , 87 e and 87 f and lid aperture 83 adapted to receive center column 30 .
FIG. 4 b illustrates a sectional view of an alternate embodiment of lid 80 for geometrically optimized cooler 100 . In the embodiment shown, lid 80 further includes insulating layer 85 .
FIG. 4 c illustrates an exploded view of one embodiment of geometrically optimized beverage cooler 100 with lid 40 .
FIG. 5 illustrates an embodiment of geometrically optimized beverage cooler 100 with lid 40 in place. In the embodiment shown, geometrically optimized cooler further includes optional drip pan 90 .
In other embodiments, geometrically optimized beverage cooler 100 may further include additional structural features including, but not limited to a rotating base, or rubber feet. In various other embodiments, geometrically optimized beverage cooler 100 may include a drainage component including, but not limited to a drainage pan, drainage holes, or a drainage spout. | The present invention is a geometrically optimized beverage cooler, which positions fluid-filled containers (bottles, cans, vials, syringes, etc.) in an angled, upright, and evenly spaced position for serving and display. The device uniformly distributes ice and cold water around each bottle to maximize the effective cooling capacity of a given quantity of ice, thus reducing the amount of ice needed and the weight of the device during transport. Various embodiments of the apparatus include an ergonomically and structurally reinforced handle and an insulating lid having complementary contours. | 5 |
This is a continuation of application U.S. Ser. No. 08/156,653, filed on Nov. 22, 1993, now abandoned, which is a continuation of U.S. Ser. No. 08/005,204, filed Jan. 15, 1993, now abandoned, which is a continuation of U.S. Ser. No. 07/449,356, filed Dec. 21, 1989, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/301,192, filed Jan. 24, 1989, which issued as U.S. Pat. No. 5,235,049 on Aug. 10, 1993, and a continuation-in-part of U.S. Ser. No. 07/445,951, filed Dec. 13, 1989.
BACKGROUND OF THE INVENTION
The present invention relates to a soluble form of intercellular adhesion molecule (sICAM-1) as well as the DNA sequence encoding sICAM-1. sICAM-1 and ICAM-1 have substantial similarity, in that they share the first 442 NH 2-terminal amino acids of the extracellular domain. However, sICAM-1 differs from ICAM-1 at the C-terminus., and these changes confer solubility to sICAM-1. ICAM-1 is known to mediate adhesion of many cell types, including endothelial cells, to lymphocytes which express lymphocyte function-associated antigen-1 (LFA-1). ICAM-1 has the property of directly binding LFA-1. There is also evidence for LFA-1 mediated adhesion which is not via ICAM-1. Additionally, ICAM-1 has the ability to bind both LFA-1 and human rhinovirus. It has the property of inhibiting infection of rhinovirus and Coxsackie A viruses. It may be used to antagonize adhesion of cells mediated by ICAM-1 binding including ICAM-1/LFA-1 binding and thus be useful in treatment of inflammation, graft rejection, LFA-1 expressing tumors, and other processes involving cell adhesion. Based on the substantial similarity of the extracellular domains of ICAM-1 and sICAM-1, sICAM-1 has the properties identified for ICAM-1.
The major Human Rhinovirus Receptor (HRR) has been transfected, identified, purified and reconstituted as described in co-pending U.S. patent applications Ser. No. 262570 and 262428 filed Oct. 25, 1988 both now abandoned. This receptor has been shown to be identical to a previously described cell surface protein, ICAM-1. European Patent Application 0 289 949 describes a membrane associated cell adhesion molecule (ICAM-1) which mediates attachment of many cell types including endothelial cells to lymphocytes which contain LFA-1. This patent application provides a discussion of the present research in the field of intercellular adhesion molecules. It is important to note that the inventors specifically looked for an alternatively spliced mRNA for ICAM-1 and did not identify one. ICAM-1 was first identified based on its role in adhesion of leukocytes to T-cells (Rothlein, R. et al J. Immunol. 137: 1270-1274 (1986)) which has been shown to be mediated by the heterotypic binding of ICAM-1 to LFA-1 (Marlin et al, Cell 51: 813-819 (1987)). The primary structure of ICAM-1 has revealed that it is homologous to the cellular adhesion molecules Neural Cell Adhesion Molecule (NCAM) and Mylein-Associated Glycoprotein (MAG), and has led to the proposal that it is a member of the immunoglobulin supergene family (Simmons et al, Nature 331: 624-627 (1988); Staunton et al, Cell 52: 925-933 (1988) The DNA sequence of cDNA clones are described in the above referenced papers by Simmons et al and Staunton et al, supra, from which the amino acid sequence of ICAM-1 can be deduced. The ICAM-1 molecule has a typical hydrophobic membrane spanning region containing 24 amino acids and a short cytoplasmic tail containing 28 amino acids. The ICAM-1 of the prior art is an insoluble molecule which is solubilized from cell membranes by lysing the cells in a non-ionic detergent. The solubilized ICAM-1 mixture in detergent is then passed through a column matrix material and then through a monoclonal antibody column matrix for purification.
SUMMARY OF THE INVENTION
The present invention provides an endogenous alternatively spliced molecular species of ICAM-1 designated sICAM-l which displays an alternative MRNA sequence and which is soluble without the addition of a detergent.
The present invention provides purified and isolated human soluble intercellular adhesion molecule (sICAM-1), or a functional derivative thereof, substantially free of natural contaminants. sICAM-1 can be obtained from HeLa, He1 and primary transfectant cells thereof characterized by being soluble in the absence of nonionic detergents and being the translation product defined by a novel mRNA sequence. This natural product of human cells has the advantage of being secreted from cells in a soluble form and not being immunogenic. The natural soluble product differs from the natural insoluble product in that the soluble product contains a novel sequence of 11 amino acid residues at the C-terminus and does not contain the membrane spanning and cytoplasmic domains present in the insoluble form.
The present invention provides a purified and isolated DNA sequence encoding sICAM-1 as well as a host cell encoding said sequence.
The present invention provides a method of recovering soluble intercellular adhesion molecule in substantially pure form comprising the steps of:
(a) removing the supernatant from unlysed cells,
(b) introducing the supernatant to an affinity matrix containing immobilized antibody capable of binding to sICAM-1,
(c) permitting said sICAM-1 to bind to said antibody of said matrix,
(d) washing said matrix to remove unbound contaminants, and
(e) recovering said sICAM-1 in substantially pure form by eluting said sICAM-1 from said matrix.
Further purification utilizing a lectin or wheat germ agglutinin column may be used before or after the antibody matrix step. Other purification steps could include sizing chromatography, ion chromatography, and gel electrophoresis. Further purification by velocity sedimentation through sucrose gradients may be used. The antibody capable of binding to sICAM-1 could include antibodies against ICAM-1 or HRR.
The present invention includes polyclonal antibodies against sICAM-1.
The present invention further includes an antibody specific for sICAM-1, capable of binding to the sICAM-1 molecule and that is not capable of binding to ICAM-1. For a method for producing a peptide antisera see Green et al, Cell 28: 477-487 (1982).
The invention also includes a hybridoma cell line capable of producing such an antibody.
This invention further includes the therapeutic use of antibodies specifically directed to sICAM-1 to increase the adhesion of cells mediated by ICAM-1 and LFA-1.
The invention further includes a method for producing an antibody which is capable of binding to sICAM-1 and not to ICAM-1 comprising the steps of
(a) preparing a peptide-protein conjugate said peptide-protein conjugate specific to at least a portion of the unique 11 amino acid sequence present in sICAM-1,
(b) immunizing an animal with said peptide-protein conjugate,
(c) boosting the animals, and
(d) obtaining the antisera.
The antibodies would be capable of binding to sICAM-1 and not capable of binding to ICAM-1. The invention includes the hybridoma cell line which produces an antibody of the same specificity, the antibody produced by the hybridoma cell and the method of production.
The invention further includes a method of inhibiting lymphocyte function associated antigen (LFA-1) and intercellular adhesion molecule-1 (ICAM-1) interaction comprising the step of contacting LFA-1 containing cells with sICAM-1 or a functional derivative thereof. This method of inhibition of ICAM-1 adhesion has application in such disease states as inflammation, graft rejection, and for LFA-1 expressing tumor cells.
This invention further includes a method of diagnosis of the presence and location of an LFA-1 expressing tumor cell.
This invention further includes a method for substantially reducing the infection of human rhinoviruses of the major receptor group comprising the step of contacting the virus with sICAM-1 or a functional derivative thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B shows the nucleotide (SEQ ID NO: 10) and amino acid (SEQ ID NO: 11) sequence of sICAM-1.
FIG. 2 is a comparision of the C-terminal regions of sICAM-1 and ICAM-1. The nucleotide (SEQ ID NO: 12) and deduced amino acid (SEQ ID NO: 13) sequences of ICAM-1 and sICAM-1 (SEQ ID NO: 11) are shown beginning at amino acid residue 435. Dashes in the sICAM-1 sequence indicate missing nucleotides. The positions of the stop codons in both proteins are indicated by an asterisk.
FIG. 3 is a comparison of the structure of sICAM-1 and ICAM-1. The membrane spanning region of ICAM-1 is indicated by the stippled box and the cytoplasmic domain by the hatched box. The novel C-terminus of sICAM-1 is indicated by the solid box. The five predicted domains showing homology with immunoglobulin are numbered I to V.
FIGS. 4A, B and C show the ICAM-1 gene and its expression in HRR transfectants. FIG. 4A: Southern blot of HeLa (Lane 1), LTk- (Lane 2) and He1 (Lane 3) DNA restricted with Eco Ri and probed with the oligonucleotide ICAM-1; FIG. 4B: Northern blot of HeLa (Lane 1), Ltk- (Lane 2), and He1 (Lane 3). poly A+ RNA probed with the oligonucleotide ICAM-1; FIG. 4C: PCR amplification of CDNA prepared from HeLa (Lane 1), Ltk - (Lane 2) and He1 (Lane 3) poly A+ RNA. The primers used were from the N-terminal and C-terminal coding regions of ICAM-1 having the sequence ggaattcATGGCTCCCAGCAGCCCCCGGCCC SEQ ID NO: 1 and ggaattcTCAGGGAGGCGTGGCTTGTGTGTT SEQ ID NO: 2. Upper case denotes ICAM-1 sequence, lower case restriction site linkers. Lanes 1 and 2, 72 hour exposure, Lane 3, 90 minute exposure.
FIG. 5 is a gel showing the detection of the ICAM-1 and sICAM-1 mRNAs in HeLa and He1 cells. PCR amplification was performed on 100 ng single stranded CDNA using the primers PCR 5.4 (CTTGAGGGCACCTACCTCTGTCGG SEQ ID NO: 3) and PCR 3.4 (AGTGATGATGACAATCTCATACCG SEQ ID NO: 1). Extensions were performed at 72 C for 25 cycles and one tenth of the product was analysed on a 1% agarose/3% NuSieve gel. Lane 1, HeLa cDNA; lane 2, He1 cDNA; lane 3, LTK - cDNA; lane 4, ICAM-1 phage control; lane 5, sICAM-1 phage control; lane 6, ICAM-1+sICAM-1 phage control. Specific amplification products of 105 bp and 86 bp are indicated by the arrows.
FIG. 6 is a Western blot showing the synthesis of a soluble form of ICAM-1 protein by HeLa and HE1 cells. It demonstrates the existence of a protein species in the culture supernatant of HeLa and HE1 cells related to ICAM-1. Equivalent aliquots of cell lysates and culture supernatants were separated by SDS-PAGE, blotted onto nitrocellulose, and probed with a rabbit polyclonal antisera to ICAM-1 followed by 125 I protein A; a species migrating close to the position of membrane-bound ICAM-1 is seen in both HeLa and He1 culture supernatants.
FIGS. 7A and B are graphical representation of the cloned sICAM-1 and ICAM-1 plasmids.
FIG. 7A. pHRR3 is a full length cDNA encoding sICAM-1 obtained by PCR. Clones 19.1-3 and 4.5 are partial cDNA clones encoding sICAM-1 obtained from an He1 cDNA library in lambda GT11. Beneath the clones is a schematic of the sICAM-1 molecule. S denotes the signal peptide and I to V the IgG homologous domains. The solid box indicates the unique 11 amino acid C-terminus.
FIG. 7B. pHRR1 and pHRR2 are full length ICAM-1 cDNA clones obtained by PCR. The remaining ICAM-1 clones were obtained from an He1 cDNA library in lambda GT11. Beneath the clones is a schematic of the ICAM-1 molecule, showing the signal peptide (S), the five IgG homologous domains (I to V), the transmembrane region (TM) and the cytoplasmic domain (C).
DESCRIPTION OF THE PREFERRED EMBODIMENTS
One aspect of the present invention relates to the discovery of a soluble natural binding ligand to the receptor binding site of Human Rhinovirus (HRV) and which also binds to LFA-1. This soluble natural molecule is related to but distinct from the molecule designated "Intercellular Adhesion Molecule-1" or "ICAM-1" which is insoluble, bound to the cell membrane and possesses a typical hydrophobic membrane spanning region and a short cytoplasmic tail. The novel protein of the present invention has a DNA sequence which includes a significant difference from the published DNA sequence for ICAM-1. sICAM-1 contains most of the extracellular domain of ICAM-1, which includes the functional domains for multiple functions including HRV and LFA-1 binding, but lacks the membrane spanning and cytoplasmic domains. sICAM-1 retains the ability to bind HRV and LFA-1 and is secreted in a soluble form. The DNA sequence for sICAM-1 contains a deletion of 19 base pairs from nucleotide 1465 to 1483 according to the numbering of Staunton et al, sudra (1988). The remainder of the sICAM-1 clone matches the published ICAM-1 sequence with the exception of a substitution of a A for G at nucleotide position 1462 which changes Glu 442 to Lys, as shown in FIG. 1B. The sequence of amino acid residues in a peptide is designated in accordance with standard nomenclature such as Lehninger's Biochemistry, Worth Publishers, New York, N.Y. (1970). sICAM-1 is a natural product of HeLa and He1 cells and other human cells which should have the property of binding to and inhibiting the infection of human rhinovirus and Coxsackie A viruses. It also has the property of binding to LFA-1 and may be used to antagonize adhesion of cells mediated by ICAM-1/LFA-1 binding and thus be useful as a therapeutic in treatment of inflammation, graft rejection, suppression of LFA-1 expressing tumor cells and other processes involving cell adhesion. Isolated and purified sICAM-1 protein as a therapeutic would not possess the immunogenic problems associated with foreign proteins. The secretion of a soluble naturally occurring protein eliminates the problems associated with production and purification of an insoluble, cell membrane bound protein, since cell lysis is not required and thus continuous culture can be employed as well as simplified procedures for purification and isolation of sICAM-1.
Non-human mammalian cell lines which express the major human rhinovirus receptor gene have been previously identified and are the subject matter of copending U.S. patent application Ser. No. 262570 and 262428 filed Oct. 25, 1988, both now abandoned, and include references to the ATCC deposits for the cell lines. The major human rhinovirus receptor was identified with monoclonal antibodies which inhibit rhinovirus infection. These monoclonal antibodies recognized a 95 kd cell surface glycoprotein on human cells and on mouse transfectants expressing a rhinovirus-binding phenotype. Purified 95 Kd protein binds to rhinovirus in vitro. Protein sequence from the 95 kd protein showed an identity with that of ICAM-1; a cDNA clone obtained from mouse transfectants expressing the rhinovirus receptor had the same sequence published for ICAM-1, except for the A for G change previously described. Thus it was determined that the major human rhinovirus receptor and ICAM-1 were the same protein. A transfected mouse L-cell line designated HEI had been isolated which contained and expressed the HRR gene or ICAM-1 gene. The ICAM-1 terminology has been used although it is now recognized that HRR and ICAM-1 are interchangeable.
A randomly primed cDNA library was prepared in lambda GT1l from He1 polyA+ RNA. The library was screened in duplicate using two oligonucleotides derived from the published sequence of ICAM-1. Oligonucleotide ICAM-1 has the sequence GAGGTGTTCTCAAACAGCTCCAGCCCTTGGGGCCGCAGGTCCAGTTC SEQ ID NO: 5 and oligonucleotide ICAM-3 has the sequence CGTTGGCAGGACAAAGGTCTGGAGCTGGTAGGGGGCCGAGGTGTTCT SEQ ID NO: 6.
Eight positive clones were obtained from one screen and three were selected for further study. DNA sequencing of two of the clones showed identity with the published ICAM-1 sequence. The sequence of the third clone, lambda 19.1-3 was significantly different from the other two clones in that there was a deletion of 19 bp from nucleotide 1465 to 1483 according to the numbering of Staunton et al, supra. The 19 bp deletion was present in a second cDNA, lambda HE1-4.5 and independently confirmed using polymerase chain reaction (PCR) generated cDNA. Analysis of the cDNA sequence predicted the existence of a secreted form of ICAM-1 that is generated by an alternative splicing mechanism. Western blot identification of sICAM-1 from culture supernatants of He1 and HeLa cell lines confirm that the sICAM-1 MRNA sequence encodes a soluble form of ICAM-1 that does not associate with the cell surface but is released into the cell medium. An alternatively spliced MRNA generating a secreted form of another adhesion molecule (NCAM) has been identified (Glower et al, Cell 55:955-964 (1988)), although in NCAM an exon is incorporated into the mRNA while in the present invention an exon is deleted from the mRNA. No alternative mRNA sequence for ICAM-1 had previously been identified. (Staunton et al.)
sICAM-1 cDNA Clones
A randomly primed cDNA library was constructed in lambda GT11 from He1 poly A+ by Clontech Laboratories, Palo Alto, Calif. The library was screened with two 47 mer oligonucleotide probes from the middle of the ICAM-1 coding sequence. A positive clone designated 19.1-3 was isolated which had an insert of 1.5 kb; a second cDNA clone designated 4.5 which has an insert of 1.25 kb was isolated; and an additional cDNA clone pHRR-3 was obtained by subcloning the products of PCR amplification into Bluescript utilizing the Perkin-Elmer/Cetus DNA Amplification System, Perkin Elmer, Wellesley Mass., as shown in FIG. 4C, lane 3. These clones showed a significant difference from the published ICAM-1 sequence. They all contain a deletion of 19 base pairs from nucleotide 1465 to 1483 according to the numbering of Staunton et al, supra. In order to demonstrate directly that the s-ICAM mRNA is present in He1 cells and HeLa cels, a PCR experiment was performed using primers which flank the 19 bp region which is absent from the S-ICAM mRNA (FIG. 8). Using these primers the product from the ICAM-1 mRNA is 105 bp while the s-ICAM-1 product is 19 bp shorter i.e. 86 bp. This experiment shows that both HEI cells and HeLa cells contain both forms of the ICAM-1 MRNA while the control L-cells do not. A synthetic oligonucleotide designated PCR3.2 having the following sequence:
ggaattcTCACTCATACCGGGGGGAGAGCACATT SEQ ID NO: 7 was used to distinguish between cDNA clones containing the 19 bp deletion from clones not containing the 19 bp deletion. The synthetic oligonucleotide does not bind to cDNA clones which contain the 19 bp deletion. In addition, partial sequence of the cDNA 19.1-3 and PHRR-3 confirmed the 19 bp deletion. This data indicates that there are at least two different and distinct ICAM-1 species in He1 cells. The insoluble ICAM-1 of the prior art and a novel soluble form as described in the present invention.
The sequences of the deleted (sICAM-1) and the nondeleted (ICAM-1) forms of the Intercellular Adhesion Molecule-1 mRNA represented by the cDNA clones are shown in FIG. 2. The sequence at the point of deletion is AGGT consistent with an RNA splice junction. The removal of 19 bases from the mRNA shifts the reading frame and causes the two polypeptide sequences to diverge at amino acid residue 443. The deleted form (sICAM-1) contains an additional 11 residues followed by an in-frame termination codon. This molecule thus consists of 453 amino acids as compared to 505 amino acids for the nondeleted form. Beginning with the N-terminus of ICAM-1, sICAM-1 has 442 amino acids in common with ICAM-1. The deleted form (sICAM-1) contains a unique 11 amino acid C-terminus but lacks the membrane spanning (24 amino acids) and cytoplasmic tail 28 amino acids) domains of ICAM-1, as shown in FIG. 3.
ICAM-1 cDNA Clones
A plurality of methods may be used to clone genes. One method is to use two partially overlapping 47mer oligonucleotide probes. These two probes termed oligonucleotide ICAM-1 and oligonucleotide ICAM-3 were synthesized from the published ICAM-1 sequence. The ICAM-1 oligonucleotide was labeled to high specific activity and hybridized to a Southern blot under high stringency conditions. As shown in FIG. 4A, a single band of 4.4 kb was detected in HeLa, He1 and two primary HRR transfectant cell lines and was absent from Ltk- cells. This result confirms that the HRR transfectants contain the human ICAM-1 gene. The size of the fragment agrees with Simmons et al but differs from Staunton et al probably reflecting a restriction site polymorphism.
The ICAM-1 oligonucleotide was used to probe a Northern blot of poly A+ RNA from the same cell lines. As shown in FIG. 4B, an mRNA of 3.3 kb was detected in HeLa, HE1, and primary transfectant cell lines but was absent from Ltk - cells. The signal in He1 cells was many times stronger than the other cell lines indicating a much higher level of mRNA in HE1 cells. This is in agreement with the higher level of HRR (ICAM-1) expression in He1 cells. A second 2.4 kb RNA was also detected in He1 cells. These data confirm that the human ICAM-1 mRNA is expressed in HRR transfectants. See FIG. 4B.
The human ICAM-1 gene was isolated from the HE1 transfectant using polymerase chain reaction (PCR) amplification utilizing the Perkin-Elmer/Seats DNA Amplification System, Perkin Elmer, Wellesley Mass. PCR amplification was performed on single stranded cDNA made from HeLa, Ltd - and He1 RNA. Primers were made from the 5' and 3' coding regions of the published ICAM-1 sequence. ICAM-1 specific amplification products were detected by hybridization of a Southern blot of the PCR reactions using the ICAM-1 oligonucleotide. As shown in FIG. 4C, a single band of approximately 1600 bp which matches the predicted size was amplified from HeLa cells and He1 cells but was absent from Ltk - cells. The amplification product was cloned into Bluescript (Strategene, San Diego, Calif.) and two independent clones designated PHRR1 and PHRR2 were obtained. The complete sequence of PHRR2 showed 100% identity with the published ICAM-1 coding sequence with the exception of a single A to G change previously described.
A lambda GT11 library made from randomly primed HEI cDNA was screened with the ICAM-1 and ICAM-3 probes and eight positive clones were isolated. Six clones as shown in FIG. 7 were selected for further study and were analyzed by partial DNA sequencing. A total of approximately 1000 nucleotides of sequence derived from these clones showed identity with the ICAM-1 sequence.
Purification and Isolation of Soluble Protein
HeLa and He1 cells are grown under standard conditions in DMEM (Dulbecco's Modified Essential Media) with 10% Fetal Bovine Serum. Conditioned media from these cells is harvested and centrifuged or filtered to remove cells or cellular debris. The cell-membrane bound ICAM-1 is not present in the supernatant. This media is then absorbed to a monoclonal antibody-sepharose resin (the monoclonal antibody c78.4A being an example) in which the monoclonal antibody is directed to ICAM-1 or sICAM-1 and the unabsorbed proteins are washed from the resin with a physiological saline buffer, such as phosphate-buffered saline. The bound sICAM-1 is then eluted under conditions that preserve the native conformation of the protein, as described in copending application Ser. No. 262428 filed Oct. 25, 1988 now abandoned. The sICAM-1 may be further purified by lectin affinity chromatography, ion exchange chromatography, or gel filtration.
mRNA transcribed in vitro from cDNA encoding sICAM in the Bluescript vector (Strategene) was translated in vitro. In the absence of microsomal membranes, an unglycosylated protein with an apparent MW of 52,000 daltons was obtained; in the presence of microsomal membranes, a glycosylated species of 72,400 daltons was obtained which was sequestered within the microsomal membrane, indicating that the sICAM polypeptide is correctly translocated, processed, and glycosylated by the microsomal membranes.
cDNA's encoding tmICAM and sICAM in the CDM8 vector (Seed, B. and Aruffo, A. PNAS 84:3365 (1987) were transfected into COS cells and mouse L cells using the DEAE-dextran technique. AT 72 hra the cells were analyzed by two methods: (1) FACS analysis with anti-ICAM Mab (c78.4) for cell membrane expression of ICAM species and (2) metabolic labeling followed by immunoabsorption with anti-ICAM Mab of cell supernatants and cell lysates. The results from the metabolic labelling indicated intracellular accumulation of a 68,000 dalton species in sICAM-transfected cells but no detectable secretion of sICAM into the supernatant. These data are consistent with sICAM being secreted through the "Regulated" secretory pathway (R. B. Kelly, Science 230:25 (1985)).
Antibody probes specific for sICAM and for ICAM-1 were prepared. The synthetic peptides S-PEP,
P P G M R L S S S L W (C) SEQ ID NO: 8
derived from a unique 11 amino acid sequence at the C-terminus of sICAM, and P002, derived from the C-terminus of ICAM-1,
G T P M K P N T Q A T P P (C) SEQ ID NO: 9
was made and purified; the C-terminal C residues in parentheses were added to facilitate coupling of the peptides to protein carriers. The synthetic peptide was coupled to KLH (Keyhole Limpet Hemocyanin) by standard procedures and the conjugate injected into rabbits to produce anti-peptide antisera were shown to specifically bind to their respective peptide immunogens.
__________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 13(2) INFORMATION FOR SEQ ID NO:1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 31 bases(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: other nucleic acid(iii) HYPOTHETICAL: no(iv) ANTI-SENSE: no(ix) FEATURE:(A) NAME/KEY: PCR 5.1 (5'PCR primer)(B) LOCATION: 5'end of ICAM-1 coding sequence(D) OTHER INFORMATION: bp 1 = G; bp 2-7 = EcoRIsite; bp 8- 31 = 24 bases coding for the firsteight amino acid residues of hICAM-1(x) PUBLICATION INFORMATION:(A) AUTHORS: Greve, J.M., G. Davis, A.M. Meyer,C.P. Forte, S.C. Yost, C.W. Marlor, M.E.Kamarck, and A. McClelland(B) TITLE: The Major Human Rhinovirus Receptor isICAM-1(C) JOURNAL: Cell(D) VOLUME: 56(F) PAGES: 839-847(G) DATE: March 10, 1989(K) RELEVANT RESIDUES IN SEQ ID NO:1: FROM 1 TO31(xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:GGAATTCATGGCTCCCAGCAGCCCCCGGCCC31MetAlaProSerSerProArgPro(2) INFORMATION FOR SEQ ID NO:2:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 31 bases(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: other nucleic acid(iii) HYPOTHETICAL: no(iv) ANTI-SENSE: yes(ix) FEATURE:(A) NAME/KEY: PCR 3.1 (3'PCR primer)(B) LOCATION: 3'end of ICAM-1 coding sequence(D) OTHER INFORMATION: base 1 =G; base 2-7 =EcoRI site; base 8-31 = 24 basescomplementary to nucleic acid sequence codingfor last 8 amino acid residues of hICAM-1(x) PUBLICATION INFORMATION:(A) AUTHORS: Greve, J.M., G. Davis, A.M. Meyer,C.P. Forte, S.C. Yost, C.W. Marlor, M.E.Kamarck, and A. McClelland(B) TITLE: The Major Human Rhinovirus Receptor isICAM-1(C) JOURNAL: Cell(D) VOLUME: 56(F) PAGES: 839-847(G) DATE: March 10, 1989(K) RELEVANT RESIDUES IN SEQ ID NO:2: FROM 1 TO31(xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:GGAATTCTCAGGGAGGCGTGGCTTGTGTGTT31(2) INFORMATION FOR SEQ ID NO:3:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 24 bases(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: other nucleic acid(iii) HYPOTHETICAL: no(iv) ANTI-SENSE: no(ix) FEATURE:(A) NAME/KEY: PCR 5.4 (5'PCR primer)(B) LOCATION: nucleotides 1351 to 1374 of sICAM(xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:CTTGAGGGCACCTACCTCTGTCGG24LeuGluGlyThrTyrLeuCysArg5(2) INFORMATION FOR SEQ ID NO:4:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 24 bases(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: other nucleic acid(iii) HYPOTHETICAL: no(iv) ANTI-SENSE: yes(ix) FEATURE:(A) NAME/KEY: 3'PCR primer(B) LOCATION: complementary to nucleotides 1432 -1455 of sICAM(xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:AGTGATGATGACAATCTCATACCG24(2) INFORMATION FOR SEQ ID NO:5:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 47 bases(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: other nucleic acid(iii) HYPOTHETICAL: no(iv) ANTI-SENSE: yes(ix) FEATURE:(A) NAME/KEY: ICAM1 probe(B) LOCATION: complementary to nucleotides 565 to611 of ICAM- 1(x) PUBLICATION INFORMATION:(A) AUTHORS: Greve, J.M., G. Davis, A.M. Meyer,C.P. Forte, S.C. Yost, C.W. Marlor, M.E.Kamarck, and A. McClelland(B) TITLE: The Major Human Rhinovirus Receptor isICAM-1(C) JOURNAL: Cell(D) VOLUME: 56(F) PAGES: 839-847(G) DATE: March 10, 1989(K) RELEVANT RESIDUES IN SEQ ID NO:5: FROM 1 TO47(xi) SEQUENCE DESCRIPTION: SEQ ID NO:5:GAGGTGTTCTCAAACAGCTCCAGCCCTTGGGGCCGCAGGTCCAGTTC47(2) INFORMATION FOR SEQ ID NO:6:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 47 bases(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: other nucleic acid(iii) HYPOTHETICAL: no(iv) ANTI-SENSE: yes(ix) FEATURE:(A) NAME/KEY: ICAM3 probe(B) LOCATION: complementary to nucleotides 602 to648 of human ICAM(x) PUBLICATION INFORMATION:(A) AUTHORS: Greve, J.M., G. Davis, A.M. Meyer,C.P. Forte, S.C. Yost, C.W. Marlor, M.E.Kamarck, and A. McClelland(B) TITLE: The Major Human Rhinovirus Receptor isICAM-1(C) JOURNAL: Cell(D) VOLUME: 56(F) PAGES: 839-847(G) DATE: March 10, 1989(K) RELEVANT RESIDUES IN SEQ ID NO:6: FROM 1 TO47(xi) SEQUENCE DESCRIPTION: SEQ ID NO:6:CGTTGGCAGGACAAAGGTCTGGAGCTGGTAGGGGGCCGAGGTGTTCT47(2) INFORMATION FOR SEQ ID NO:7:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 34 bases(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: other nucleic acid(iii) HYPOTHETICAL: no(iv) ANTI-SENSE: yes(ix) FEATURE:(A) NAME/KEY: PCR 3.2 antisense(D) OTHER INFORMATION: base 1 =G; bases 2-7 =EcoR1 site; bases 8-10 = complementary to astop codon; bases 11-34 = 24 basescomplementary to nucleotides 1474-1497 ofICAM-1, nucleotide 1 being the ATG(xi) SEQUENCE DESCRIPTION: SEQ ID NO:7:GGAATTCTCACTCATACCGGGGGGAGAGCACATT34(2) INFORMATION FOR SEQ ID NO:8:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 12 amino acid residues(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE:(A) DESCRIPTION: peptide(iii) HYPOTHETICAL: no(v) FRAGMENT TYPE: modified C-terminal fragment(ix) FEATURE:(A) NAME/KEY: modified sICAM fragment(B) LOCATION: C-terminus of sICAM(D) OTHER INFORMATION: first 11 amino acidscorrespond to C-terminus of sICAM; lastresidue (Cys) added to faciliate coupling(xi) SEQUENCE DESCRIPTION: SEQ ID NO:8:ProProGlyMetArgLeuSerSerSerLeuTrpCys510(2) INFORMATION FOR SEQ ID NO:9:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 14 amino acid residues(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE:(A) DESCRIPTION: peptide(iii) HYPOTHETICAL: no(v) FRAGMENT TYPE: C-terminal fragment(ix) FEATURE:(A) NAME/KEY: modified ICAM fragment(B) LOCATION: C-terminus(D) OTHER INFORMATION: first 11 amino acidresidues correspond to the C-terminus ofICAM; last residue (Cys) added to faciliatecoupling(xi) SEQUENCE DESCRIPTION: SEQ ID NO:9:GlyThrProMetLysProAsnThrGlnAlaThrProProCys14510(2) INFORMATION FOR SEQ ID NO:10:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 1443 bases(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA to mRNA(iii) HYPOTHETICAL: no(iv) ANTI-SENSE: no(vi) ORIGINAL SOURCE:(A) ORGANISM: human(G) CELL TYPE: epithelial(H) CELL LINE: HeLa(vii) IMMEDIATE SOURCE:(A) LIBRARY: cDNA library(ix) FEATURE:(A) NAME/KEY: human sICAM cDNA to mRNA sequence(B) LOCATION: nucleotides 1 to 1435 numberedbeginning at ATG coding for first Met ofhuman sICAM protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:10:ATGGCTCCCAGCAGCCCCCGGCCCGCGCTGCCCGCACTCCTGGTC45MetAlaProSerSerProArgProAlaLeuProAlaLeuLeuVal51015CTGCTCGGGGCTCTGTTCCCAGGACCTGGCAATGCCCAGACATCT90LeuLeuGlyAlaLeuPheProGlyProGlyAsnAlaGlnThrSer202530GTGTCCCCCTCAAAAGTCATCCTGCCCCGGGGAGGCTCCGTGCTG135ValSerProSerLysValIleLeuProArgGlyGlySerValLeu354045GTGACATGCAGCACCTCCTGTGACCAGCCCAAGTTGTTGGGCATA180ValThrCysSerThrSerCysAspGlnProLysLeuLeuGlyIle505560GAGACCCCGTTGCCTAAAAAGGAGTTGCTCCTGCCTGGGAACAAC225GluThrProLeuProLysLysGluLeuLeuLeuProGlyAsnAsn657075CGGAAGGTGTATGAACTGAGCAATGTGCAAGAAGATAGCCAACCA270ArgLysValTyrGluLeuSerAsnValGlnGluAspSerGlnPro808590ATGTGCTATTCAAACTGCCCTGATGGGCAGTCAACAGCTAAAACC315MetCysTyrSerAsnCysProAspGlyGlnSerThrAlaLysThr95100105TTCCTCACCGTGTACTGGACTCCAGAACGGGTGGAACTGGCACCC360PheLeuThrValTyrTrpThrProGluArgValGluLeuAlaPro110115120CTCCCCTCTTGGCAGCCAGTGGGCAAGAACCTTACCCTACGCTGC405LeuProSerTrpGlnProValGlyLysAsnLeuThrLeuArgCys125130135CAGGTGGAGGGTGGGGCACCCCGGGCCAACCTCACCGTGGTGCTG450GlnValGluGlyGlyAlaProArgAlaAsnLeuThrValValLeu140145150CTCCGTGGGGAGAAGGAGCTGAAACGGGAGCCAGCTGTGGGGGAG495LeuArgGlyGluLysGluLeuLysArgGluProAlaValGlyGlu155160165CCCGCTGAGGTCACGACCACGGTGCTGGTGAGGAGAGATCACCAT540ProAlaGluValThrThrThrValLeuValArgArgAspHisHis170175180GGAGCCAATTTCTCGTGCCGCACTGAACTGGACCTGCGGCCCCAA585GlyAlaAsnPheSerCysArgThrGluLeuAspLeuArgProGln185190195GGGCTGGAGCTGTTTGAGAACACCTCGGCCCCCTACCAGCTCCAG630GlyLeuGluLeuPheGluAsnThrSerAlaProTyrGlnLeuGln200205210ACCTTTGTCCTGCCAGCGACTCCCCCACAACTTGTCAGCCCCCGG675ThrPheValLeuProAlaThrProProGlnLeuValSerProArg215220225GTCCTAGAGGTGGACACGCAGGGGACCGTGGTCTGTTCCCTGGAC720ValLeuGluValAspThrGlnGlyThrValValCysSerLeuAsp230235240GGGCTGTTCCCAGTCTCGGAGGCCCAGGTCCACCTGGCACTGGGG765GlyLeuPheProValSerGluAlaGlnValHisLeuAlaLeuGly245250255GACCAGAGGTTGAACCCCACAGTCACCTATGGCAACGACTCCTTC810AspGlnArgLeuAsnProThrValThrTyrGlyAsnAspSerPhe260265270TCGGCCAAGGCCTCAGTCAGTGTGACCGCAGAGGACGAGGGCACC855SerAlaLysAlaSerValSerValThrAlaGluAspGluGlyThr275280285CAGCGGCTGACGTGTGCAGTAATACTGGGGAACCAGAGCCAGGAG900GlnArgLeuThrCysAlaValIleLeuGlyAsnGlnSerGlnGlu290295300ACACTGCAGACAGTGACCATCTACAGCTTTCCGGCGCCCAACGTG945ThrLeuGlnThrValThrIleTyrSerPheProAlaProAsnVal305310315ATTCTGACGAAGCCAGAGGTCTCAGAAGGGACCGAGGTGACAGTG990IleLeuThrLysProGluValSerGluGlyThrGluValThrVal320325330AAGTGTGAGGCCCACCCTAGAGCCAAGGTGACGCTGAATGGGGTT1035LysCysGluAlaHisProArgAlaLysValThrLeuAsnGlyVal335340345CCAGCCCAGCCACTGGGCCCGAGGGCCCAGCTCCTGCTGAAGGCC1080ProAlaGlnProLeuGlyProArgAlaGlnLeuLeuLeuLysAla350355360ACCCCAGAGGACAACGGGCGCAGCTTCTCCTGCTCTGCAACCCTG1125ThrProGluAspAsnGlyArgSerPheSerCysSerAlaThrLeu365370375GAGGTGGCCGGCCAGCTTATACACAAGAACCAGACCCGGGAGCTT1170GluValAlaGlyGlnLeuIleHisLysAsnGlnThrArgGluLeu380385390CGTGTCCTGTATGGCCCCCGACTGGACGAGAGGGATTGTCCGGGA1215ArgValLeuTyrGlyProArgLeuAspGluArgGluCysProGly395400405AACTGGACGTGGCCAGAAAATTCCCAGCAGACTCCAATGTGCCAG1260AsnTrpThrTrpProGluAsnSerGlnGlnThrProMetCysGln410415420GCTTGGGGGAACCCATTGCCCGAGCTCAAGTGTCTAAAGGATGGC1305AlaTrpGlyAsnProLeuProGluLeuLysCysLeuLysAspGly425430435ACTTTCCCACTGCCCATCGGGGAATCAGTGACTGTCACTCGAGAT1350ThrPheProLeuProIleGlyGluSerValThrValThrArgAsp440445450CTTGAGGGCACCTACCTCTGTCGGGCCAGGAGCACTCAAGGGGAG1395LeuGluGlyThrTyrLeuCysArgAlaArgSerThrGlnGlyGlu455460465GTCACCCGCAAGCCCCCCGGTATGAGATTGTCATCATCACTGTGG1440ValThrArgLysProProGlyMetArgLeuSerSerSerLeuTrp470475480TAG1443(2) INFORMATION FOR SEQ ID NO:11:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 480 amino acid residues(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE:(A) DESCRIPTION: protein(iii) HYPOTHETICAL: no(vi) ORIGINAL SOURCE:(A) ORGANISM: human(B) CELL TYPE: epithelial(C) CELL LINE: HeLa cells(ix) FEATURE:(A) NAME/KEY: sICAM-1(D) OTHER INFORMATION: amino acid sequenceidentical to ICAM-1 protein sequence exceptfor residue 442, which is Lys rather thanGlu, and residues 443-453, which is novelsequence due to alternative splicing(xi) SEQUENCE DESCRIPTION: SEQ ID NO:11:MetAlaProSerSerProArgProAlaLeuProAlaLeuLeuVal51015LeuLeuGlyAlaLeuPheProGlyProGlyAsnAlaGlnThrSer202530ValSerProSerLysValIleLeuProArgGlyGlySerValLeu354045ValThrCysSerThrSerCysAspGlnProLysLeuLeuGlyIle505560GluThrProLeuProLysLysGluLeuLeuLeuProGlyAsnAsn657075ArgLysValTyrGluLeuSerAsnValGlnGluAspSerGlnPro808590MetCysTyrSerAsnCysProAspGlyGlnSerThrAlaLysThr95100105PheLeuThrValTyrTrpThrProGluArgValGluLeuAlaPro110115120LeuProSerTrpGlnProValGlyLysAsnLeuThrLeuArgCys125130135GlnValGluGlyGlyAlaProArgAlaAsnLeuThrValValLeu140145150LeuArgGlyGluLysGluLeuLysArgGluProAlaValGlyGlu155160165ProAlaGluValThrThrThrValLeuValArgArgAspHisHis170175180GlyAlaAsnPheSerCysArgThrGluLeuAspLeuArgProGln185190195GlyLeuGluLeuPheGluAsnThrSerAlaProTyrGlnLeuGln200205210ThrPheValLeuProAlaThrProProGlnLeuValSerProArg215220225ValLeuGluValAspThrGlnGlyThrValValCysSerLeuAsp230235240GlyLeuPheProValSerGluAlaGlnValHisLeuAlaLeuGly245250255AspGlnArgLeuAsnProThrValThrTyrGlyAsnAspSerPhe260265270SerAlaLysAlaSerValSerValThrAlaGluAspGluGlyThr275280285GlnArgLeuThrCysAlaValIleLeuGlyAsnGlnSerGlnGlu290295300ThrLeuGlnThrValThrIleTyrSerPheProAlaProAsnVal305310315IleLeuThrLysProGluValSerGluGlyThrGluValThrVal320325330LysCysGluAlaHisProArgAlaLysValThrLeuAsnGlyVal335340345ProAlaGlnProLeuGlyProArgAlaGlnLeuLeuLeuLysAla350355360ThrProGluAspAsnGlyArgSerPheSerCysSerAlaThrLeu365370375GluValAlaGlyGlnLeuIleHisLysAsnGlnThrArgGluLeu380385390ArgValLeuTyrGlyProArgLeuAspGluArgGluCysProGly395400405AsnTrpThrTrpProGluAsnSerGlnGlnThrProMetCysGln410415420AlaTrpGlyAsnProLeuProGluLeuLysCysLeuLysAspGly425430435ThrPheProLeuProIleGlyGluSerValThrValThrArgAsp440445450LeuGluGlyThrTyrLeuCysArgAlaArgSerThrGlnGlyGlu455460465ValThrArgLysProProGlyMetArgLeuSerSerSerLeuTrp470475480(2) INFORMATION FOR SEQ ID NO:12:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 240 bases(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA to mRNA(iii) HYPOTHETICAL: no(iv) ANTI-SENSE: no(vi) ORIGINAL SOURCE:(A) ORGANISM: human(G) CELL TYPE: epithelial(H) CELL LINE: HeLa(vii) IMMEDIATE SOURCE:(A) LIBRARY: cDNA library(ix) FEATURE:(A) NAME/KEY: partial human ICAM cDNA to mRNAsequence(B) LOCATION: nucleotides 1384 to 1623 numberedbeginning at ATG coding for first Met ofhuman ICAM protein(x) PUBLICATION INFORMATION:(A) AUTHORS: Greve, J.M., G. Davis, A.M. Meyer,C.P. Forte, S.C. Yost, C.W. Marlor, M.E.Kamarck, and A. McClelland(B) TITLE: The Major Human Rhinovirus Receptor isICAM-1(C) JOURNAL: Cell(D) VOLUME: 56(F) PAGES: 839-847(G) DATE: March 10, 1989(K) RELEVANT RESIDUES IN SEQ ID NO:10: FROM 1 TO240(xi) SEQUENCE DESCRIPTION: SEQ ID NO:12:ACTCAAGGGGAGGTCACCCGCAAGGTGACCGTGAATGTGCTCTCC45ThrGlnGlyGluValThrArgLysValThrValAsnValLeuSer51015CCCCGGTATGAGATTGTCATCATCACTGTGGTAGCAGCCGCAGTC90ProArgTyrGluIleValIleIleThrValValAlaAlaAlaVal202530ATAATGGGCACTGCAGGCCTCAGCACGTACCTCTATAACCGCCAG135IleMetGlyThrAlaGlyLeuSerThrTyrLeuTyrAsnArgGln354045CGGAAGATCAAGAAATACAGACTACAACAGGCCCAAAAAGGGACC180ArgLysIleLysLysTyrArgLeuGlnGlnAlaGlnLysGlyThr505560CCCATGAAACCGAACACACAAGCCACGCCTCCCTGAACCTATC223ProMetLysProAsnThrGlnAlaThrProPro6570CCGGGACAGGGCCTCTT240(2) INFORMATION FOR SEQ ID NO:13:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 221 bases(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA to mRNA(iii) HYPOTHETICAL: no(iv) ANTI-SENSE: no(vi) ORIGINAL SOURCE:(A) ORGANISM: human(G) CELL TYPE: epithelial(H) CELL LINE: HeLa(vii) IMMEDIATE SOURCE:(A) LIBRARY: cDNA library(ix) FEATURE:(A) NAME/KEY: partial human sICAM-1 cDNA to mRNAsequence(B) LOCATION: sequence from human sICAMcorresponding to nucleotides 1384 to 1623 ofhuman ICAM lacking bp 1407 to 1426,inclusive, of hICAM(xi) SEQUENCE DESCRIPTION: SEQ ID NO:13:ACTCAAGGGGAGGTCACCCGCAAGCCCCCCGGTATGAGATTGTCA45ThrGlnGlyGluValThrArgLysProProGlyMetArgLeuSer51015TCATCACTGTGGTAGCAGCCGCAGTCATAATGGGCACTGCAGGCCTCAGCAC97SerSerLeuTrpGTACCTCTATAACCGCCAGCGGAAGATCAAGAAATACAGACTACAACAGG147CCCAAAAAGGGACCCCCATGAAACCGAACACACAAGCCACGCCTCCCTGA197ACCTATCCCGGGACAGGGCCTCTT221__________________________________________________________________________ | The present invention relates to a soluble form of intercellular adhesion molecule (sICAM-1) and purified and isolated human sICAM-1. This invention also relates to a purified and isolated DNA sequence encoding sICAM-1. The extracellular domain of sICAM-1 and insoluble ICAM-1 are substantially the same. ICAM-1 is involved in the process through which lymphocytes attach to cellular substrates during inflammation and serves as the major human rhinovirus receptor (HRR). sICAM-1 therefore has both the property of reducing immune inflammation and inhibiting infection of rhinovirus and Coxsackie A virus. | 2 |
[0001] The invention relates to a supporting sleeve for use in a tube coupling and a tube coupling for use together with such a supporting sleeve, as disclosed in the preamble of the succeeding claims 1 and 9 .
PRIOR ART
[0002] Supporting sleeves are used in tube couplings, in particular in those which contain a clamping ring and/or a sealing ring, as an internal stiffening against compressing of a tube inserted in the coupling, in order to prevent that the tube collapses due to the pressure from outside exerted by the clamping ring and/or sealing ring. This may in particular occur when the tube is of a soft material, but also when the clamping ring and/or sealing ring exerts a high pressure against the outside of the tube. Thereby, the sealing around the tube and/or the retaining thereof may become insufficient.
[0003] NO Patent 149598 shows an example of a coupling which contains a supporting sleeve made integrally with a coupling housing.
[0004] Moreover, it is known to insert separate supporting sleeves in coupling housings. As examples reference is made to DE Patent Application 2450126, showing a supporting sleeve attached on the end of the tube inserted in the coupling housing in that the tube has internal grooves at the end. This solution makes it necessary to machine the tube end in order to form the grooves. EP Patent Application 0546405 shows a separate supporting sleeve having an end portion with a conical external shape, adapted to a conical surface in a coupling housing. Moreover, the end portion has an annular groove, into which the end of a tube can be inserted. The supporting sleeve will not be kept in place in the coupling housing before a second coupling housing has been screwed on.
[0005] With the present invention has been provided a supporting sleeve which in a simple manner is retained in a coupling housing upon insertion, and a tube coupling for use together with such a supporting sleeve.
[0006] The supporting sleeve and the tube coupling according to the invention are characterized by the features appearing from the preceeding claims 1 and 9 . Embodiments of the supporting sleeve are specified in the claims 2 - 8 .
SUMMARY OF THE INVENTION
[0007] Because the supporting sleeve has a collar which is externally conical, the supporting sleeve may simply be inserted in a cylindrical bore in the coupling housing, and because the diameter of the collar in undeformed state of the collar exceeds the diameter of the bore, the collar will in inserted state form an obstruction against pulling out the supporting sleeve. The bore in the coupling housing may have an annular groove into which the edge of the collar will protrude. The collar may have a correspondingly increased radial dimension, whereby the collar is deformed in the mounted state of the supporting sleeve.
[0008] Preferably the coupling housing comprises a second bore in the succession of the bore into which the supporting sleeve is inserted, and this second bore is adapted to an extension of the supporting sleeve, whereby the supporting sleeve is centered in the coupling housing and aligned with the longitudinal axis of the coupling housing. Without such a second bore there is a possibility of inserting the supporting sleeve in such a manner that it is not exactly aligned with the longitudinal axis of the coupling housing, and the retaining of the supporting sleeve may be impaired. Moreover, the insertion of a tube in the coupling housing may be more difficult. The second bore and the extension of the supporting sleeve also cause that the supporting sleeve is kept centered along the longitudinal axis even if it is subjected to an external strain, such as impacts or strokes.
[0009] The invention will in the following be explained with reference to the accompanying drawings, which show longitudinal sections through examples of a coupling with a coupling housing containing a supporting sleeve, according to the invention.
EXPLANATION OF THE DRAWINGS
[0010] [0010]FIG. 1 shows a coupling housing which contains a supporting sleeve according to the invention.
[0011] [0011]FIG. 2 shows a coupling socket which has been screwed onto the coupling housing and which contains a clamping ring and two O-rings, and a third O-ring is jammed between the coupling socket and the coupling housing.
[0012] [0012]FIG. 3 shows the coupling of FIG. 2 and the end of a tube having been inserted into the coupling.
[0013] [0013]FIG. 4 shows approximately the same as FIG. 2, and shows a coupling housing formed in accordance with the invention, somewhat differently shaped internally than the coupling housing shown in the FIGS. 1-3.
DESCRIPTION OF EMBODIMENTS
[0014] The Figs. show a supporting sleeve 1 according to the invention, comprising a first cylindrical portion 2 , an external conical collar 3 and an extension 4 . The supporting sleeve 1 is shown mounted in a coupling housing 5 , which in the example shown is formed with a nut portion 6 , for instance with an external hexagonal shape in order to be screwed by means of a wrench. Moreover, the coupling housing 5 comprises a first, externally threaded stub 7 for screwing on of a coupling socket which in screwed-on state may contain a clamping ring and/or a sealing ring around the cylindrical portion of the supporting sleeve 2 , and a second, externally threaded stub 8 for attaching the coupling housing 5 to another member. Instead of being formed with the stub 8 the coupling housing may be symmetrical about a transverse middle plane and comprise two oppositely directed stubs 7 for screwing on of two coupling sockets, whereby the coupling may be used for joining two tubes. Thereby, each half of the coupling will contain a supporting sleeve 1 .
[0015] The supporting sleeve 1 is in the examples shown made as a single piece. The cylindrical portion 2 constitutes the active part of the supporting sleeve, by stiffening a tube being inserted in the coupling against external pressure from a clamping ring and/or a sealing ring which in the mounted state surround the tube externally of the portion 2 , as shown in FIG. 3. An annulus 9 for insertion of the end of a tube into the coupling housing externally of the portion 2 is mainly adapted to the wall thickness of the inserted tube. The collar 3 causes that the supporting sleeve 1 is retained, and constitutes an end abutment for an inserted tube. The extension 4 constitutes a guide for the supporting tube 1 during insertion into the coupling housing 5 and ensures that the supporting sleeve 1 will be aligned with the longitudinal axis of the coupling housing. In the example shown the extension 4 has a somewhat smaller length and outer diameter than the portion 2 , because the extension 4 is not to be exposed to external pressure.
[0016] The collar 3 has in the example shown a conical shape externally as well as internally, and in such a manner that the external conus angle is smaller than the internal conus angle; i.e. that the axial thickness of the collar 3 decreases radially outwardly. This means that the stiffness of the collar also decreases outwardly. The collar 3 may also be planar on the upper side.
[0017] The circumferential edge of the collar 3 is in the example shown somewhat deformed upon insertion, and will press against the wall of the bore due to its elasticity. Due to the conicity of the collar 3 the collar will tend to widen if an attempt is made to pull the supporting sleeve 1 out of the coupling housing, and the resistance against pulling out will increase. The bore in the coupling housing 5 may, as shown in FIG. 4, have an annular groove 17 at the inner end, for accommodating the edge of the collar 3 . The collar 3 may have a correspondingly increased radial dimension, whereby the collar is deformed in the mounted state of the supporting sleeve. Also with such an embodiment the collar 3 will tend to widen if an attempt is made to pull the supporting sleeve 1 out of the coupling housing 5 .
[0018] [0018]FIG. 2 shows the same coupling housing 5 and the same supporting sleeve 1 as FIG. 1. A coupling socket 10 is here screwed onto the coupling housing 5 , and contains a clamping ring 11 and two O-rings 13 and 14 . A third O-ring 15 causes sealing between the coupling housing 5 and the coupling socket 10 .
[0019] [0019]FIG. 3 shows the same coupling as FIG. 2 and in addition an end of a tube 16 having been inserted into the coupling by being forced through the clamping ring 11 and the O-rings 13 and 14 . It appears that an edge 12 on the clamping ring has been forced somewhat into the tube wall, for retaining of the tube.
[0020] [0020]FIG. 4 shows mainly the same as FIG. 3, the difference being that the coupling housing 5 is formed with an annular groove 17 at the bottom of the bore which defines the annulus 9 accomodating the tube 16 , whereby the outer edge of the collar 3 on the supporting sleeve 1 has expanded into the annular groove 17 when the insertion of the supporting sleeve 1 has been completed. As the collar 3 has a somewhat larger radial dimension than the annular groove 17 , the edge of the collar 3 presses against the wall of the annular groove 17 . Thereby, the supporting sleeve 1 is locked in the bore.
[0021] The supporting sleeve does not need to be unitary as shown. For instance, the collar 3 may be a part mounted on the remainder of the supporting sleeve. The collar 3 may for instance be fastened by being snapped into an annular groove in the portion 2 , by being pressed onto the portion 2 or by being glued to the portion 2 . This is particularly of interest if it is desirable that the collar is to be of another material than the remainder of the supporting sleeve.
[0022] In particular plastics are suited as material for the supporting sleeve, or at least for the collar 3 , and preferably hard plastics. When the collar 3 constitutes a separate part, the remainder of the supporting sleeve may for instance be of metal.
[0023] The supporting sleeve 1 will give a large resistance against being pulled out, as long as it is aligned with the longitudinal axis of the coupling housing. When the tube has been removed from the coupling housing (upon screwing off the coupling socket 10 which contains the clamping ring 10 and/or the sealing rings 13 and 14 ), the supporting sleeve may, however, be forced into a somewhat inclined position, whereby the retention thereof in the bore is weakened, and it may be pulled out of the coupling housing 5 . | A supporting sleeve that is to be used in a tube coupling. The supporting sleeve causes an internal stiffening against compression of the end of a tube inserted in the coupling. The supporting sleeve is a separate part that is mounted in a bore in the coupling. The supporting sleeve includes a deformable collar that externally is conical and narrows in the direction of insertion. The edge of the collar has a diameter mainly corresponding to or exceeding the diameter of the bore. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a data processing terminal and a method and a program for causing the same to transfer to a desired tag and more particularly to a method of searching for and displaying part of a home page including a desired tag.
[0003] 2. Description of the Background Art
[0004] It is a common practice with a Web terminal or similar data processing terminal to use HTML (Hyper Text Markup Language) browser software for watching a homepage. The HTML browser software will be simply referred to as an HTML browser hereinafter. Also, other browser software will be simply referred to as a browser. Assume that the operator of the data processing terminal desires to make inquiries about a homepage, which the operator is watching with the HTML browser. Then, the operator usually searches for a portion where the mail address attribute, e.g., MailTo of an anchor tag or, in the case of an HTML browser capable of recognizing a telephone number, PhoneNo or similar telephone number attribute is indicated.
[0005] Because the HTML browser lacks means for directly searching for the tag or the attributed mentioned above, the operator is required to confirm a content designated by an anchor tag while scrolling the homepage with eye. It is to be noted that a tag refers to control information buried in a homepage. The operator is required to perform the above operation even when watching an XML (extensible Markup Language) file.
[0006] Thus, it is extremely difficult for the operator of the conventional data processing terminal to search a homepage for a desired tag or a desired attribute. For example, a browser installed in a mobile personal telephone or a PDA (Personal Digital Assistant) cannot display the entire source file at a time because of the limited area of a display screen available therewith, making it extremely difficult for the operator to grasp an attribute from the entire source file.
[0007] Technologies relating to the present invention are also disclosed in, e.g., Japanese Patent Laid-Open Publication Nos. 10-293767, 11-306205, 2000-181840 and 2002-16849 and WO 98/12871.
SUMMARY OF THE INVENTION
[0008] It is an object of the present invention to provide a data processing terminal capable of directly searching a home page for a desired tag or a desired attribute and easily transferring to the position of the desired tag or that of the desired attribute, and a method and a program for causing the same to transfer to the above position.
[0009] A data processing terminal of the present invention is configured to perform transfer to a position where, among data provided by a data provider, a tag representative of control information buried in the data exists. The terminal includes a data acquirer for acquiring the data from the data provider via a communication network, a tag analyzer for analyzing tags included in the data acquired by the data acquirer, a display device for displaying the data on the basis of the result of analysis output from the tag analyzer, and a tag searcher for searching the data for a desired tag input from the outside. The display device displays part of the data corresponding to the tag searched for by the tag searcher.
[0010] A method and a program for causing the above data processing terminal to transfer to the position of a desired tag are also disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken with the accompanying drawings in which:
[0012] [0012]FIG. 1 is a schematic block diagram showing a data processing terminal embodying the present invention;
[0013] [0013]FIG. 2 is a flowchart demonstrating a specific procedure to be executed by a tag analyzer included in the illustrative embodiment;
[0014] [0014]FIG. 3 is a schematic block diagram showing an alternative embodiment of the present invention implemented as a Web terminal;
[0015] [0015]FIG. 4 is a flowchart showing a specific operation of an HTML tag analyzer included in the embodiment of FIG. 3;
[0016] [0016]FIG. 5 shows specific transition of a picture effected by an HTML browser included in the embodiment of FIG. 3;
[0017] [0017]FIG. 6 is a flowchart showing a specific operation of the HTML tag analyzer representative of another alternative embodiment of the present invention;
[0018] [0018]FIG. 7 shows specific transition of a picture effected by the HTML browser included in the embodiment of FIG. 6;
[0019] [0019]FIG. 8 shows specific transition of a picture effected by the HTML browser representative of still another alternative embodiment of the present invention; and
[0020] [0020]FIG. 9 is a flowchart demonstrating a specific procedure to be executed by the tag analyzer representative of a further embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] Referring to FIG. 1 of the drawings, a data processing terminal embodying the present invention is shown and generally designated by the reference numeral 1 . As shown, the data processing terminal 1 is generally made up of a received data processing section 11 , an input device 12 , a display device 13 and a recording medium 14 and connected to a data provider 2 via a communication network 100 .
[0022] The communication network 100 may be any one of Internet, intranet and other communicating means. Also, the data provider 2 may be any one of data providing means of the kind providing a file that can be designated by a tag in the event of, e.g., display, e.g., an XML server, an HTML server, an XHTML (extensible Hyper Text Markup Language) server or a data base. A tag refers to control data buried in a file to be provided, as stated earlier.
[0023] The received data processing section 11 includes an input controller 111 , a display layout circuit 112 , a tag analyzer 113 including a tag searcher 113 a , and a data acquirer 114 . The received data processing section 11 , which may be constituted by software, is implemented by a computer, not shown, capable of executing a program stored in the recording medium 14 . The input controller 111 controls the input device 12 .
[0024] The received data processing section 11 transfers information on the data provider 2 input via the input device 12 to the data acquirer 114 and then acquires data from the data acquirer 2 via the communication network 100 . When the received data processing section 11 receives data from the data provider 2 , the tag analyzer 113 analyzes tags included in the received data. Subsequently, display data generated by the display layout circuit 112 are displayed on the display device 13 .
[0025] [0025]FIG. 2 demonstrates a specific procedure to be executed by the tag analyzer 113 . The operation of the illustrative embodiment will be described with reference to FIGS. 1 and 2. First, transfer to the position of a desired tag or that of a desired attribute and included in the display data appearing on the display device 13 will be described. It is to be noted that the procedure shown in FIG. 2 is included in the program of the recording medium 14 to be executed by the computer. The following description will concentrate on transfer to part of the display data where PhoneNo is described by way of example. PhoneNo is one of telephone number tag attributes customary with browser software (simply browser hereinafter) that can recognize telephone numbers.
[0026] Before the procedure of FIG. 2, the operator of the data processing terminal 1 , watching the display data on the display device 13 , inputs a character train indicative of a desired tag or a desired attribute on the input device 12 , which is controlled by the input controller 111 . The operator then presses a processing start key, not shown, located at an adequate position. In response, the tag searcher 113 a included in the tag analyzer 113 determines whether or not a tag character train to be searched for is designated (step S 1 , FIG. 2). If the answer of the step S 1 is positive (YES), then the tag searcher 113 a searches the received data for the tag character train. (step S 2 ).
[0027] Subsequently, the tag analyzer 113 determines, based on the result of the step S 2 , whether or not the designated tag character train is present in the display data being watched (step S 3 ). If the answer of the step S 3 is YES, then the tag analyzer 113 generates display data representative of a portion including the desired tag (step S 5 ) and delivers the display data thus generated to the display layout circuit 112 . The display layout circuit 112 lays out the display data and causes the display device 13 to display the resulting display data.
[0028] On the other hand, if the answer of the step S 1 is negative (NO), then the tag analyzer 113 determines that received data are to be displayed for the first time or redisplayed. In this case, the tag analyzer 113 analyzes tags included in the received data as usual (step S 4 ) and then generates display data corresponding to the received data (step S 5 ).
[0029] As stated above, the illustrative embodiment realizes easy transfer to the position of a desired tag included in display data, which correspond to received data. This makes it unnecessary for the operator to scroll display data while watching the display data and confirm a content designated by an anchor tag with eye, thereby noticeably simplifying transfer to a desired tag position.
[0030] Reference will be made to FIG. 3 for describing an alternative embodiment of the present invention and implemented as a Web terminal. As shown, the Web terminal, generally 3 , includes an HTML browser 31 , an input device 32 , a display device 33 and a recording medium 34 and connected to an HTML server 4 via Internet 200 .
[0031] The HTML browser 31 includes an input controller 311 , an HTML data acquirer 314 , an HTML tag analyzer 313 including a tag searcher 313 a , and a display layout circuit 312 . Generally, the HTML browser 31 is constituted by software and implemented by a computer, not shown, which is associated with the Web terminal 3 and executes a program stored in the recording medium 34 . The input controller 311 controls the input device 32 .
[0032] The HTML browser 31 transfers a URL (Uniform Resource Locator) input via the input device 32 to the HTML data acquirer 314 and then acquires HTML data from the HTML server 4 via Internet 200 . Subsequently, in the HTML browser 31 , the HTML tag analyzer 313 analyzes tags included in the HTML data. Thereafter, homepage display data arranged by the display layout circuit 312 are displayed on the display device 33 .
[0033] [0033]FIG. 4 demonstrates a specific procedure to be executed by the HTML tag analyzer 313 while FIG. 4 shows specific transition of a picture effected by the HTML browser 31 . The operation of the Web terminal 3 will be described with reference to FIGS. 3 through 5. It is to be noted that the procedure shown in FIG. 4 is included in the program of the recording medium 34 to be executed by the computer.
[0034] Transfer to the position of a desired tag or that of a desired attribute included in a homepage being watched will be described hereinafter. Again, the following description will concentrate on transfer to part of the homepage where. PhoneNo is described by way of example.
[0035] First, the operator of the Web terminal 3 , watching a homepage (picture P 1 , FIG. 5), inputs a character train (PhoneNo) indicative of a desired tag or a desired attribute, which is indicated in italic in the picture P 1 for distinction. A picture P 2 in FIG. 5 shows the resulting condition of the homepage. The operator then presses a processing start key, not shown, located at an adequate position. In response, the HTML tag analyzer 313 causes its tag searcher 313 a to determine whether or not a tag character train to be searched for is present (step S 1 , FIG. 4). If the answer of the step S 11 is YES, then the tag searcher 313 a searches the HTML data for the tag character train (PhoneNo) (step S 12 ).
[0036] The tag analyzer 313 determines, based on the result of search performed by the tag searcher 313 a , whether or not the tag character train is present (step S 13 ). If the answer of the step S 13 is YES, meaning that the designated tag character train (PhoneNo) is present on the homepage, then the HTML tag analyzer 313 generates display data corresponding to a portion including the designated tag (step S 15 ).
[0037] The homepage display data thus generated are laid out by the display layout circuit 312 and then displayed on the display device 33 (pictureP 3 , FIG. 5). As a result, in the illustrative embodiment, the picture P 3 , describing <A HREF=“PhoneNo:0312345678”>call</A>on the homepage, appears on the display device 33 ; “call” to which transfer is made is indicated in italics.
[0038] On the other hand, if the answer of the step S 11 is NO, then the tag analyzer 313 determines that received data are to be displayed for the first time or redisplayed. In this case, the tag analyzer 313 analyzes tags included in the received HTML data as usual (step S 14 ) and then generates homepage display data (step S 15 ).
[0039] It should be noted that the telephone number attribute PhoneNo shown and described is merely a specific tag attribute to be searched for and may be replaced with any other character train representative of, e.g., a mail address attribute MilTo. In such a case, too, transfer to the position of the desired tag will be effected if the tag is present on a homepage.
[0040] With the configuration described above, the illustrative embodiment achieves the same advantage as the previous embodiment.
[0041] [0041]FIG. 6 shows a specific operation of the HTML tag analyzer representative of another alternative embodiment of the present invention and also practicable with the Web terminal 3 shown in FIG. 3. The operation of the illustrative embodiment will be described with reference to FIGS. 3, 6 and 7 . It is to be noted that the procedure shown in FIG. 6 is included in the program of the recording medium 34 to be executed by the computer.
[0042] In the illustrative embodiment, because the number of tags available with a homepage is limited, the HTML tag analyzer searches for all tags present on an HTML file (step S 21 , FIG. 6). The tags thus searched for are displayed in the form of a pop-up menu (step S 22 ) (see a picture P 2 ′, FIG. 7). When the operator selects desired one of the tags included in the pop-up menu, steps S 23 through S 27 are sequentially executed in the same manner as the steps S 11 through S 15 of FIG. 4. As a result, homepage display data are generated, laid out by the display layout circuit 312 , and then displayed on the display device 33 (see a picture P 3 , FIG. 7).
[0043] In the picture P 2 ′ of FIG. 7, a telephone number attribute PhoneNo and a mail address attribute MailTo searched for in the step S 21 are shown as appearing in the form of a pop-up menu by way of example.
[0044] With the configuration described above, the illustrative embodiment achieves the same advantage as the previous embodiments.
[0045] [0045]FIG. 8 shows specific transition of a picture effected by an HTML browser representative of still another alternative embodiment of the present invention. As shown, the transition differs from the transition of FIG. 7 in that a picture P 4 , which allows the operator to select the range of tags to be listed in the pop-up menu P 2 ′ beforehand, appears before the pop-up menu P 2 ′. More specifically, when the operator inputs the range of search (“where to contact” in FIG. 8) beforehand, the illustrative embodiment searches for, e.g., PhoneNo and MailTo without searching every tag of the HTML file and displays them in the pop-up menu P 2 ′.
[0046] With the configuration described above, the illustrative embodiment achieves the same advantage as the previous embodiments.
[0047] [0047]FIG. 9 shows another specific operation of the tag analyzer representative of a further alternative embodiment of the present invention. This embodiment is also practicable with the data processing terminal shown in FIG. 1 and will therefore be described with reference to FIGS. 1 and 9. It is to be noted that the procedure shown in FIG. 9 is included in the program of the recording medium 14 to be executed by the computer. The illustrative embodiment is applied to transfer to a tag position included in an XML file.
[0048] As shown in FIG. 9, the tag analyzer 113 searches the XML file for all tags present therein (step S 31 ) and then excludes “TITLE” and other reserved words of general use, which are not effective for information search, from the range of search (step S 32 ). Further, the tag analyzer 113 lowers the ranking of tags not defined by DTD (Document Type Definition), i.e., searches for tags defined by DTD prior to the others (steps S 33 and S 34 ). One or both of the steps S 32 and S 33 may be executed, as the case may be.
[0049] The tags of the XML file thus searched for are displayed in order of ranking in the form of a pop-up menu (step S 35 ). When the operator selects a desired tag in the pop-up menu, i.e., when a tag character train to be searched for is input (YES, step S 36 ), the tag searcher 113 a searches the XML data for the designated tag character train (step S 37 ).
[0050] The tag analyzer 113 determines, based on the result of search performed by the tag searcher 113 a , whether or not the desired tag character train is present in the display data (step S 38 ). If the answer of the step S 38 is YES, then display data corresponding to the desired tag are generated (step S 40 ), laid out by the display layout circuit 112 , and then displayed on the display device 13 .
[0051] If the answer of the step S 38 is NO, meaning that the operator has not selected any tag listed in the pop-up menu, then the tag analyzer 113 determines that received data are to be displayed for the first time or redisplayed. In this case, the tag analyzer 113 analyzes tags included in the received data as usual (step S 39 ) and then generates display data corresponding to the received data (step S 40 ).
[0052] With the configuration described above, the illustrative embodiment also achieves the same advantage as the previous embodiments.
[0053] In summary, in accordance with the present invention, it is possible to directly search for a desired tag or a desired attribute on a homepage and easily, immediately transfer to a position where the attribute exists. This makes it unnecessary for the operator to confirm a content designated by an anchor tag with eye while scrolling a homepage, thereby noticeably simplifying transfer to a desired tag position. This is also true with a mobile personal telephone, PDA (Personal Data Assistant) or similar personal apparatus whose display screen is small.
[0054] Various modifications will become possible for those skilled in the art after receiving the teachings of the present disclosure without departing from the scope thereof. | A data processing terminal of the present invention is configured to perform transfer to a position where, among data provided by a data provider, a tag representative of control information buried in the data exists. The terminal includes a data acquirer for acquiring the data from the data provider via a communication network, a tag analyzer for analyzing tags included in the data acquired by the data acquirer, a display device for displaying the data on the basis of the result of analysis output from the tag analyzer, and a tag searcher for searching the data for a desired tag input from the outside. The display device displays part of the data corresponding to the tag searched for by the tag searcher. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method capable of stably drawing an optical fiber with a gas-seal system and an apparatus for implementing the method
[0003] 2. Description of the Background Art
[0004] Optical fibers are produced by the following process. First, an optical fiber preform made of silica glass or another material is fed into a drawing apparatus. The leading-end portion of the optical fiber preform is heated and softened in the drawing furnace. The softened leading end is drawn downward to reduce the diameter. The drawing furnace is provided with a muffle tube and a heater, which are made of carbon in many cases. In this case, these members must be protected from oxidation by using an inert gas as the atmospheric gas in the furnace. In addition, the surface of the optical fiber preform must be maintained clean during the drawing operation in order to secure longitudinal uniformity of the drawn optical fiber. To meet the foregoing two requirements, the drawing furnace is structured so as not to make contact with the optical fiber preform, and the space between the muffle tube and the optical fiber preform is filled with an inert gas to form a gas-seal structure so that the oxidation of the muffle tube and the heater can be prevented, in many cases.
[0005] An example of the gas-seal structure is shown in the published Japanese patent application Tokukaishou 62-176938. In this example, the inert gas is fed by blowing it onto the optical fiber preform at the top portion of the drawing furnace. The blown inert gas hits the optical fiber preform to divide into an upward-flowing stream and a downward-flowing stream. The upward-flowing stream prevents oxygen from entering at the clearance between the optical fiber preform and the muffle tube. The downward-flowing stream prevents oxygen from entering from under by flowing toward a shutter located at the bottom portion of the drawing furnace after suppressing the upward flow of the atmospheric gas due to the heat in the furnace. The above-described gas streams maintain the pressure inside the drawing furnace higher than that of the atmosphere at all times.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is to offer a method capable of stably drawing an optical fiber with a gas-seal system and an apparatus for implementing the method.
[0007] According to the present invention, the foregoing object is attained by offering the following method of drawing an optical fiber. This method comprises the following steps:
[0008] (a) feeding an optical fiber preform into a drawing furnace;
[0009] (b) adjusting the inner diameter of a seal ring located at the top portion of the drawing furnace while feeding the optical fiber preform;
[0010] (c) feeding a gas into the drawing furnace such that the gas hits the optical fiber preform and produces a stream that flows out at the clearance between the seal ring and the optical fiber preform; and
[0011] (d) drawing the optical fiber by heating and softening the leading-end portion of the optical fiber preform.
[0012] The above-described step of adjusting the inner diameter of the seal ring may be performed based on the diameter of the optical fiber preform. The foregoing step may also be performed in such a way that the inside pressure of a muffle tube placed in the drawing furnace becomes constant.
[0013] According to one aspect of the present invention, the present invention offers the following apparatus for drawing an optical fiber by heating the leading-end portion of an optical fiber preform while feeding it into a drawing furnace. This apparatus comprises:
[0014] (a) a gas-sealing structure comprising a seal ring and a gas feeder capable of blowing a gas against the optical fiber preform;
[0015] (b) a seal-ring actuator capable of adjusting the inner diameter of the seal ring; and
[0016] (c) a controller for controlling the seal-ring actuator.
[0017] Advantages of the present invention will become apparent from the following detailed description, which illustrates the best mode contemplated to carry out the invention. The invention can also be carried out by different embodiments, and its several details can be modified in various respects, all without departing from the invention. Accordingly, the accompanying drawing and the following description are illustrative in nature, not restrictive.
BRIEF DESCRIPTION OF THE DRAWING
[0018] The present invention is illustrated to show examples, not to show limitations, in the figures of the accompanying drawing. In the drawing, the same reference numeral and sign refer to a similar element.
[0019] In the drawing:
[0020] [0020]FIG. 1 is a schematic diagram showing an embodiment of the optical fiber-drawing apparatus of the present invention.
[0021] [0021]FIG. 2 is a schematic diagram showing a relative position between the opening of a seal ring and a small-diameter optical fiber preform.
[0022] [0022]FIG. 3 is a schematic diagram showing a relative position between the opening of a seal ring and a large-diameter optical fiber preform.
[0023] [0023]FIG. 4 is a schematic diagram showing a relative position between a seal ring and an optical fiber preform when the optical fiber preform is in an eccentric position with respect to the drawing apparatus.
[0024] [0024]FIG. 5 is a graph showing the relationship between the diameter and longitudinal position of optical fiber preforms A, B, C, and D used in individual embodiments.
[0025] [0025]FIG. 6 is a graph-showing the relationship between the maximum deviation of the diameter of the glass fiber and the corresponding longitudinal position of the optical fiber preform A from which the diameter-measured position of the glass fiber is drawn.
[0026] [0026]FIG. 7 is a graph showing the relationship between the maximum deviation of the diameter of the glass fiber and the corresponding longitudinal position of the optical fiber preform B from which the diameter-measured position of the glass fiber is drawn.
[0027] [0027]FIG. 8 is a graph showing the relationship between the maximum deviation of the diameter of the glass fiber and the corresponding longitudinal position of the optical fiber preform C from which the diameter-measured position of the glass fiber is drawn.
[0028] [0028]FIG. 9 is a graph showing the relationship between the maximum deviation of the diameter of the glass fiber and the corresponding longitudinal position of the optical fiber preform D from which the diameter-measured position of the glass fiber is drawn.
[0029] [0029]FIG. 10 is a graph showing the relationship between the diameter and longitudinal position of an optical fiber preform used in a comparative example.
[0030] [0030]FIG. 11 is a graph showing the relationship between the maximum deviation of the diameter of the glass fiber and the corresponding longitudinal position of the optical fiber preform used in the comparative example from which the diameter-measured position of the glass fiber is drawn.
DETAILED DESCRIPTION OF THE INVENTION
[0031] [0031]FIG. 1 is a schematic diagram showing an embodiment of the optical fiber-drawing apparatus of the present invention. A drawing apparatus 10 is equipped with a preform feeder 11 directly above a drawing furnace 20 . The preform feeder 11 has a clamp 12 , which holds a glass rod 31 attached to the top portion of an optical fiber preform 30 . As the preform feeder 11 descends, the optical fiber preform 30 is fed into the drawing furnace 20 .
[0032] The drawing furnace 20 is provided with a seal ring 14 U at the top portion to seal its interior against the atmosphere. Directly above the seal ring 14 U, a preform diameter monitor 13 is located to measure the diameter of the optical fiber preform 30 on a noncontact basis. Under the seal ring 14 U, a gas feeder 16 is located to feed an inert gas 15 , such as Ar, N, or He, into the drawing furnace 20 .
[0033] [0033]FIG. 2 is a schematic diagram showing a relative position between the opening of the seal ring 14 U and a small-diameter optical fiber preform 30 . FIG. 3 is a schematic diagram showing a relative position between the opening of the seal ring 14 U and a large-diameter optical fiber preform 30 . FIG. 4 is a schematic diagram showing a relative position between the seal ring 14 U and an optical fiber preform 30 when the optical fiber preform 30 is in an eccentric position with respect to the drawing apparatus. As shown in FIGS. 2 to 4 , the seal ring 14 U is composed of a so-called iris diaphragm 14 a . The iris diaphragm 14 a is operated with a seal-ring actuator 14 b so that the size of the central opening 14 c can be adjusted according to the passing optical fiber preform 30 . When the optical fiber preform 30 is in an eccentric position with respect to the drawing furnace 20 , as shown in FIG. 4, a base plate 14 d supporting the iris diaphragm 14 a is shifted right and left and backward and forward with a seal-ring shifter 14 e so that the optical fiber preform 30 can pass through the center of the seal ring 14 U.
[0034] The drawing furnace 20 is equipped at its center with a cylindrical muffle tube 21 made of carbon to allow the optical fiber preform 30 to pass through it. The drawing furnace 20 is also equipped at the outside of the muffle tube 21 with a heater 22 . A differential pressure gauge 23 is located at the bottom portion of the drawing furnace 20 to measure the pressure difference between the inside of the drawing furnace 20 and the outside atmosphere. The drawing furnace 20 is also equipped at its bottom end with a shutter 14 L, which is a seal ring similar in function to the above-described seal ring 14 U located at the top end.
[0035] A cooling pipe 50 is located under the drawing furnace 20 to cool the drawn glass fiber 40 a . A fiber diameter monitor 51 is located under the cooling pipe 50 to measure the diameter of the drawn glass fiber 40 a.
[0036] Under the fiber diameter monitor 51 , a first coating section 52 a is located to apply a coating material onto the drawn glass fiber 40 a to form a first coating, and, in succession, a second coating section 52 b is located to apply a coating material to form a second coating. Under the second coating section 52 b , a curing section 53 is located to cure the first and second coatings at the same time. When an ultraviolet cure resin (UV resin) is used for the coating, the first coating section 52 a applies a UV resin for the first coating onto the glass fiber 40 a , the second coating section 52 b applies a UV resin for the second coating, and the curing section 53 cures them by the irradiation of ultraviolet with ultraviolet lamps. When a thermosetting resin is used for the coating, the curing section 53 employs a heating device.
[0037] Thus, a drawn and coated optical fiber 40 b is formed. The optical fiber 40 b passes through a guide roller 54 by the pulling force of a capstan 55 and is wound onto a take-up reel 57 to complete the production.
[0038] The following members are connected to a controller 60 for controlling the seal-ring actuator to feed back signals of measured data or to send and receive signals for actuating directions and other information: the preform feeder 11 , the preform diameter monitor 13 , the seal-ring actuator 14 b , the seal-ring shifter 14 e , the heater 22 , the differential pressure gauge 23 , the fiber diameter monitor 51 , and the capstan 55 .
[0039] Next, the method of drawing an optical fiber of the present invention is explained below by referring to FIG. 1. The controller 60 controls the preform feeder 11 to descend the optical fiber preform 30 to feed it into the drawing furnace 20 . The diameter of the optical fiber preform 30 is measured by the preform diameter monitor 13 located directly above the seal ring 14 U, and the measured data is sent to the controller 60 . The controller 60 controls the seal-ring actuator 14 b based on the measured data of the diameter to adjust the iris diaphragm 14 a so that the difference between the inner diameter of the seal ring 14 U and the diameter of the optical fiber preform 30 can become constant.
[0040] The inert gas 15 is blown into the drawing furnace 20 from the gas feeder 16 so as to hit the optical fiber preform 30 . After hitting the optical fiber preform 30 , the inert gas 15 divides into an upward-flowing stream 15 U and a downward-flowing stream 15 L. The upward-flowing stream 15 U flows out at the clearance between the seal ring 14 U and the optical fiber preform 30 , preventing the ingress of the outside air and dust into the drawing furnace 20 . On the other hand, the downward-flowing stream 15 L flows downward through the space between the optical fiber preform 30 and the muffle tube 21 . This stream not only prevents the adhesion of impurities such as dust on the surface of the optical fiber preform 30 but also prevents the oxidation of the muffle tube 21 resulting from the contact with oxygen.
[0041] The glass fiber 40 a drawn out of the drawing furnace 20 passes through the shutter 14 L and is cooled at the cooling pipe 50 . The fiber diameter monitor 51 measures the diameter of the glass fiber 40 a to feed back the data to the controller 60 . The controller 60 controls the drawing speed of the capstan 55 based on the fed-back data of the diameter. For example, if the measured diameter is excessively small, the drawing speed is decreased. If the diameter is excessively large, the drawing speed is increased.
[0042] Subsequently, the glass fiber 40 a is coated with a coating material at the first and second coating sections 52 a and 52 b . The coating material is cured at the curing section 53 to form the coating. The coated optical fiber 40 b passes through the guide roller 54 by the pulling force of the capstan 55 and is wound onto the take-up reel 57 to complete the production.
[0043] [0043]FIG. 5 is a graph showing the relationship between the diameter and longitudinal position of optical fiber preforms A, B, C, and D used in individual embodiments. FIG. 6 is a graph showing the relationship between “the maximum deviation of the diameter of the glass fiber” and the corresponding longitudinal position of the optical fiber preform A from which the diameter-measured position of the glass fiber is drawn. Here, the expression “the maximum deviation of the diameter of the glass fiber” is used to mean the maximum difference between the predetermined diameter and the diameter of the glass fiber measured within a length of 1,000 mm including the plotted point in FIG. 6. The controller 60 controlled the seal-ring actuator 14 b based on the data of the diameter of the optical fiber preform 30 measured at the position directly above the seal ring 14 U. Thus, the controller 60 adjusted the iris diaphragm 14 a so that the difference between the inner diameter of the seal ring 14 U and the measured data of the diameter of the optical fiber preform 30 could become constant. While this adjustment was performed, the optical fiber preform A was drawn.
[0044] The time needed for the optical fiber preform A to move from the position of the preform diameter monitor 13 to the position of the seal ring 14 U is determined by the feeding speed of the optical fiber preform A. Therefore, after the diameter of the optical fiber preform A is measured, the inner diameter of the seal ring 14 U is adjusted by delaying the time for the foregoing movement. As can be seen from FIG. 6, this drawing method enables the stable drawing of an optical fiber preform throughout its length.
[0045] [0045]FIG. 7 is a graph showing the relationship between the maximum deviation of the diameter of the glass fiber and the corresponding longitudinal position of the optical fiber preform B from which the diameter-measured position of the glass fiber is drawn. The optical fiber preform B is drawn while the controller 60 controls the seal-ring actuator 14 b to adjust the iris diaphragm 14 a so that the area of the clearance between the seal ring 14 U and the optical fiber preform B can become constant. As can be seen from FIG. 7, this drawing method also enables the stable drawing of an optical fiber preform throughout its length.
[0046] [0046]FIG. 8 is a graph showing the relationship between the maximum deviation of the diameter of the glass fiber and the corresponding longitudinal position of the optical fiber preform C from which the diameter-measured position of the glass fiber is drawn. The optical fiber preform C is drawn by the following method. First, before the drawing operation, the relationship between the diameter and longitudinal position of the optical fiber preform C is obtained as shown in FIG. 5. The relative vertical position between the drawing furnace and the optical fiber preform C is also measured. During the drawing operation, based on these data, the controller 60 controls the seal-ring actuator 14 b to adjust the inner diameter of the iris diaphragm 14 a . More specifically, as soon as the position “0 mm” of the preform shown in FIG. 5 arrives at the position of the seal ring 14 U, the adjustment of the inner diameter of the seal ring 14 U is started. The diameter of the optical fiber preform C at the position of the seal ring 14 U at a specific time can be calculated from the feeding speed of the optical fiber preform C and the data shown in FIG. 5. As can be seen from FIG. 8, this drawing method also enables the stable drawing of an optical fiber preform throughout its length.
[0047] The inside pressure of the drawing furnace 20 may be controlled to be constant together with the above-described control. This pressure control can be performed by controlling the amount of the gas fed into the drawing furnace 20 based on the data of the inside pressure measured by the differential pressure gauge 23 .
[0048] [0048]FIG. 9 is a graph showing the relationship between the maximum deviation of the diameter of the glass fiber and the corresponding longitudinal position of the optical fiber preform D from which the diameter-measured position of the glass fiber is drawn. The optical fiber preform D is drawn by the following method. During the drawing operation, the inside pressure of the drawing furnace 20 is measured by the differential pressure gauge 23 . The inside pressure at the time the clearance between the seal ring 14 U and the optical fiber preform D is adjusted to be 2 mm, is used as a reference. During the drawing operation, the controller 60 controls the seal-ring actuator 14 b to adjust the inner diameter of the iris diaphragm 14 a so that the inside pressure of the drawing furnace 20 can become constant. As can be seen from FIG. 9, this drawing method also enables the stable drawing of an optical fiber preform 30 throughout its length.
[0049] The control for maintaining the inside pressure constant may be performed simultaneously with the earlier-described control for maintaining the difference between the diameter of the optical fiber preform and the inner diameter of the seal ring constant.
[0050] When a plurality of preform diameter monitors are provided, the amount of positional change in the center axis of the optical fiber preform can be measured. In the above-described control of the inner diameter of the seal ring 14 U, when the optical fiber preform 30 is in an eccentric position with respect to the 5 seal ring 14 U, as shown in FIG. 4, the controller 60 controls the seal-ring shifter 14 e to shift the seal ring 14 U so that the optical fiber preform 30 can pass through the center of the seal ring 14 U. This operation prevents the optical fiber preform 30 from coming into contact with the seal ring 14 U after becoming off-center with respect to the seal ring 14 U. As a result, the optical fiber preform can be drawn with an increased stability.
[0051] [0051]FIG. 10 is a graph showing the relationship between the diameter and longitudinal position of an optical fiber preform used in a comparative example. FIG. 11 is a graph showing the relationship between the maximum deviation of the diameter of the glass fiber and the corresponding longitudinal position of the optical fiber preform used in the comparative example from which the diameter-measured position of the glass fiber is drawn. In the comparative example, the optical fiber preform was drawn by using a muffle tube having an inner diameter of 80 mm and a seal ring having an inner diameter of 72 mm. As can be seen from FIGS. 10 and 11, when the preform diameter decreased to 69 mm, the maximum deviation of the diameter of the glass fiber increased. When the preform diameter further decreased to the vicinity of 68 mm, the maximum deviation abruptly increased in excess of 5 μm. Observation of the furnace after the drawing operation revealed marks of oxidation on the inner surface of the carbon muffle tube. In FIG. 11, the sign “X” shows the occurrence of the abrupt increase in the maximum deviation of the diameter of the glass fiber.
[0052] As described above, when the gas seal structure is employed, the variation in the clearance between the gas-feeding opening and the optical fiber preform must be maintained small. If the clearance varies, the ratio between the upward-flowing stream and the downward-flowing stream produced by the gas blown from the opening varies. More specifically, if the decreased preform diameter increases the clearance, the percentage of the stream flowing upward increases, decreasing that of the downward-flowing stream. As a result, the velocity of the downward-flowing stream decreases, making it extremely difficult to suppress the upward-flowing stream of the atmospheric gas due to the heat of the furnace. Consequently, the gas flow becomes unstable. This condition increases the variation in the diameter of the drawn glass fiber. Moreover, the outside air may enter the furnace through part of the shutter, deteriorating the inside members of the furnace by oxidation.
[0053] The above-described problem-creating tendency becomes noticeable as the preform diameter increases. In comparison with a small-diameter preform, even a small variation in the preform diameter relatively increases the variation in the area of the clearance at the gas-sealing portion. As a result, a stable drawing operation cannot be performed.
[0054] The method of and apparatus for drawing an optical fiber of the present invention can maintain the clearance between the optical fiber preform and the seal ring constant even when the diameter of the optical fiber preform 30 varies longitudinally. This feature enables the stabilized drawing operation. Consequently, the diameter of the drawn glass fiber 40 a can be maintained constant. Furthermore, the useful life of the muffle tube 21 can be increased by suppressing its oxidation.
[0055] The present invention is described above in connection with what is presently considered to be the most practical and preferred embodiments. However, the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
[0056] In the above explanation, the drawing furnace used in the embodiment has a shutter. However, the method and apparatus of the present invention can be implemented without using the shutter.
[0057] The entire disclosure of Japanese patent application 2002-329914 filed on Nov. 13, 2002 including the specification, claims, drawing, and summary is incorporated herein by reference in its entirety. | A method capable of stably drawing an optical fiber with a gas-seal system and an apparatus for implementing the method. The method produces an optical fiber 40 b by drawing the optical fiber preform 30 by heating and softening the leading-end portion of it while feeding it into a drawing furnace 20 . The drawing furnace 20 allows a gas 15 to blow against the optical fiber preform 30 . The inside of the drawing furnace 20 is sealed with a seal ring 14 U and a shutter 14 L located at the top and bottom portions of it, respectively. While the gas 15 is fed, the inner diameter of the seal ring 14 U is adjusted according to the diameter of the optical fiber preform 30 . Consequently, even when the preform diameter varies, the clearance between the seal ring 14 U and the optical fiber preform 30 can be maintained constant, thereby enabling a stable drawing operation. | 2 |
RELATED APPLICATION
[0001] This application is a continuation-in-part application of U.S. application Ser. No. 10/090201, entitled Water-Based Drilling Fluid Additive Containing Talc & Carrier which was filed on Mar. 5, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to a drilling fluid additive system manufactured by a process comprising: admixing colloidal solids such talc with a carrier (such as cellulose or a combination of oil and glycol) to create a suspended mixture to thereby allow the solids to be pre-wet with the carrier; admixing copolymer beads to the suspended mixture to thereby allow the beads to be pre-wet with the carrier and to form a drilling fluid additive mixture; and admixing hydrophilic clay, a pH controller, a fluid loss controller, and a dispersant to the drilling fluid additive mixture. More specifically, the present invention relates to an improved method of enhancing the surface of a cake wall of a well bore by adding a drilling fluid system to the well bore manufactured by the following method: admixing talc with cellulose or a combination of oil and glycol and then admixing polymer beads to the mixture, and subsequently adding this mixture with a mixture of hydrophilic clay, a pH controller, a fluid loss controller, and a dispersant.
[0004] 2. Description of the Related Art
[0005] New technology in drilling for oil and gas now includes horizontal drilling. The horizontal drilling concept exposes more surface area of the producing zone than the conventional vertical drilling operations. For example, if a producing zone is fifty feet in thickness and a vertical well is drilled through such a zone, then only fifty feet of the producing zone will be exposed for production. In contrast, a horizontally drilled well may penetrate the producing sand or zone by one thousand feet or more. The amount or volume of oil or gas production is directly proportional to the horizontal penetration in feet into the producing sand or zone. In horizontal or directional drilling where the drill pipe must bend in order to achieve the desired penetration into the producing zone, friction becomes a major problem. The primary source of friction is directly related to the adhesion of the drilling assembly to the wall cake which lines the drilled well bore. The capillary attractive forces generated by the adhesion of the drilling assembly to the wall cake are directly proportional to the amount or footage of the drilling assembly exposed to the surface of the wall cake.
[0006] In horizontal or directional wells, many methods have been used in order to reduce friction between the drilling assembly and the wall cake. One such method would be to add a liquid lubricant to the drilling fluid in order to reduce the coefficient of friction of the drilling fluid. These liquid lubricants include oils, such as hydrocarbon based oils, vegetable oils, glycols, etc. These liquid lubricants will usually reduce the coefficient of friction of the drilling fluid resulting in a reduction of friction between the drilling assembly and the wall cake of the well bore.
[0007] When the liquid lubricant is added to the drilling fluid, it has several options as to how it will react. One option is that the lubricant remains isolated and does not mix well with the drilling fluid. A second option is that the lubricant emulsifies with the water in the drilling fluid to form an oil-in-water emulsion. Still another option is the oil attaching itself to the commercial solids in the drilling fluid or to the drilled cuttings or drilled solids. In certain circumstances, some of the liquid lubricant might be deposited or smeared onto the wall cake of the well bore. The ideal scenario would be to have all of the liquid lubricant deposited on the wall cake.
[0008] Those experienced in drilling fluid engineering know that a thin, tough, pliable, and lubricious wall cake is most desirable. The integrity of a wall cake is determined by several factors. The thickness of a wall cake is directly proportional to the amount of liquid leaving the drilling fluid, and being forced into the wall of the well bore by hydrostatic pressure. The thickness of the wall cake is also determined by the type and particle size of the solids in the drilling fluid. Particle Size Distribution, or PSD is important to the wall cake integrity. Experts in drilling fluids also know that materials such as bentonite clay, starches, lignites and polymers are all used to build acceptable wall cakes. It is known in the prior art that various food grade vegetable oils are acceptable lubricants when used alone in water-based drilling fluids. It is also known in the prior art that round co-polymer beads when used alone in water-based drilling fluids function as a good friction reducer. However, much more is required to improve the wall cake integrity and lubricity of most well bores. In addition, there is no technology or process in the prior art that improves the lubrication or friction reducing capacity of the copolymer beads.
[0009] Furthermore, the solids control equipment used on the drilling rigs today is far superior as to what was used 15 to 20 years ago. In the past, drilling rig shale shakers would probably be limited to screen sizes of about 20-40 mesh on the shakers. These coarser mesh screens would allow pieces of shale and the drilled formation to pass through the shaker screens back into the drilling fluid and then recirculated back down the well bore. As these larger than colloidal size particles make their way back up the well bore to the surface, the action of the drilling assembly rotating within the well bore forces these larger particles into the surface of the well bore. For example: a 20×20 mesh shaker screen would allow a drilled cutting sized at 863 microns or 0.0340 inches to pass through it and then the cutting would be returned to the well bore and some of these 863 micron cuttings would eventually be embedded into the wall cake. This would give the wall cake surface a texture resembling that of coarse sandpaper. These larger particles would allow the drilling fluid to channel and pass between the drilling assembly and the wall cake thereby reducing the negative effect of the capillary attractive forces generated by the close contact of the drilling assembly with the wall cake. The instances of the drilling assembly becoming stuck to the wall cake when less efficient solids control equipment, such as shale shakers, was used much less than it is today. The more efficient shale shakers today are a great improvement for the drilling fluids but the instances of sticking the drilling assembly are higher. The reason for a higher rate of stuck drilling assemblies today could be blamed on cleaning the drilling fluid to efficiently. Today many drilling rigs utilize cascading shale shakers, which eventually pass the drilling fluid through 200 mesh or 74 micron screens. This is very positive for controlling the percentage of drilled solids in the drilling fluid but it also affects the texture or surface of the wall cake. The finer the solids on the surface of the wall cake are, the greater the capillary attractive forces will be between the drilling assembly and the wall cake.
[0010] The present invention provides a method of enhancing the surface of the wall cake. In order to accomplish this, the invention provides a method, which adds something to improve the texture of the surface of the wall cake, and then adds something to prevent large amounts of water from leaving the drilling fluid then passing through the wall cake into the formation. The present invention also provides a carrier for the colloidal solids and beads, which also acts as a lubricant for the drilling fluid. The present invention further provides a process that reduces the effect of capillary attractive forces between the drilling assembly and the wall cake, thereby reducing the tendency of the drilling assembly to become stuck. In high angle directional wells where down hole motors are used to rotate the drill bit and the drill pipe remains stationary, it is important that the drilling assembly can slide as the drilling bit cuts more holes. The present invention improves the ability to slide while drilling as stated above.
SUMMARY OF THE INVENTION
[0011] In one embodiment, the present invention relates to a drilling fluid additive system manufactured by a method comprising of admixing talc with an oil and a glycol to create a suspended mixture to thereby allow the talc to be pre-wet with the oil and the glycol; admixing copolymer beads to the suspended mixture to thereby allow the beads to be pre-wet with the oil and the glycol and to form a drilling fluid additive mixture, the talc and the beads having an affinity for oils, esters, glycols, cellulose and olefins; and admixing hydrophilic clay, a pH controller, a fluid loss controller, and a dispersant to the drilling fluid additive mixture.
[0012] In another embodiment, the beads are comprised of styrene and divinylbenzene. In still another embodiment, the beads have a specific gravity from about 1.0 to about 1.5 and a size from about 40 microns to about 900 microns. In yet another embodiment, the talc has a size range from about 2 microns to about 40 microns.
[0013] In still yet another embodiment, the oil and the glycol function as a lubricant. In a further embodiment, the oil consists essentially of oils, hydrocarbon oils, vegetable oils, mineral oils, paraffin oils, synthetic oils, diesel oils, animal oils and soybean oil and mixtures thereof. In still a further embodiment, the glycol consist essentially of polypropylene glycol, polyethoxylated glycol, polybutylene glycol, polyethylene glycol, propylene glycol, polyester polyol-poly(oxyethylene-oxy) propylene glycol, polyoxyalkylene glycol ethers and mixtures thereof.
[0014] In yet a further embodiment, the oil and the glycol comprises from about 10% to about 98% of the additive mixture, the talc comprises from about 2% to about 50% of the additive mixture, and the beads comprises from about 2% to about 50% of the additive mixture. In still yet a further embodiment, the system further comprises a weighting agent, said weighting agent consisting essentially of barium sulfate (barite), calcium carbonate, hematite, and salts. In another further embodiment, the system further comprises a surfactant, the surfactant being a nonionic surfactant. In still another further embodiment, the surfactant comprises a polyethoxylated glycol. In still yet another further embodiment, the pH controller consist essentially of caustic acid, potassium hydroxide and sodium hydroxide
[0015] In another embodiment, the fluid loss controller consists essentially of lignites, polyacrylamide and graphite uintaite (Gilsonite”) glycol dispersions. In still another embodiment, the hydrophilic clay consists essentially of bentonite, kaolin clay and viscosifiers. In yet another embodiment, the dispersant consists essentially of lignite and lignosulfonate. In still yet another embodiment, the system further comprises a chemical inhibitor, the chemical inhibitor consisting essentially of gypsum, lime, potassium chloride, potassium hydroxide, magnesium sulfate and calcium sulfate.
[0016] In a further embodiment, the method of manufacturing a drilling fluid additive system, the method comprising: shearing colloidal talc with cellulose to create a suspended mixture to thereby allow the talc to be coated with the cellulose and to form a drilling fluid additive mixture; and admixing hydrophilic clay, a pH controller, a fluid loss controller, and a dispersant to the drilling fluid additive mixture. For purposes of this invention, cellulose applies to both the liquid and solid (powder) forms of cellulose and the term coated shall apply to dry and wet coatings and/or treatments of cellulose. In one embodiment, the talc is pre-wet with the liquid cellulose. In another embodiment, the talc is coated with solid (powder) cellulose.
[0017] In still a further embodiment, the method further comprises admixing polymeric beads to the drilling fluid additive mixture after coating the talc with the cellulose, the talc and the beads having an affinity for oils, esters, glycols, cellulose and olefins. In yet a further embodiment, the beads have a specific gravity from about 1.0 to about 1.5 and a size from about 40 microns to about 900 microns, the beads comprise of styrene and divinylbenzene.
[0018] In still yet a further embodiment, the talc has a size range from about 2 microns to about 40 microns. In another embodiment, the cellulose comprises from about 5% to about 98% of the additive mixture, the talc comprises from about 2% to about 50% of the additive mixture, and the beads comprises from about 2% to about 50% of the additive mixture. In still another embodiment, the pH controller consists essentially of caustic acid, potassium hydroxide and sodium hydroxide. In yet another embodiment, the fluid loss controller consists essentially of lignites, polyacrylamide and graphite uintaite (Gilsonite”) glycol dispersions. In still yet another embodiment, the hydrophilic clay consists essentially of bentonite, kaolin clay and viscosifiers. In a further embodiment, the dispersant consists essentially of lignite and lignosulfonate.
[0019] In still a further embodiment, the method further comprises adding a weighting agent, said weighting agent consisting essentially of barium sulfate (barite), calcium carbonate, hematite, and salts. In yet a further embodiment, the method further comprises adding a surfactant, the surfactant being a nonionic surfactant. In still yet a further embodiment, the method further comprises adding a chemical inhibitor, the chemical inhibitor consisting essentially of gypsum, lime, potassium chloride, potassium hydroxide, magnesium sulfate and calcium sulfate. In another further embodiment, the cellulose consists essentially of polyanionic cellulose, polyanionic cellulose polymer, and carboxymethyl cellulose. In still another further embodiment, the method further comprises adding said system to a wellbore.
[0020] In yet another further embodiment, the present invention relates to a method of enhancing the surface of a wall cake of a well bore, the method comprising: shearing colloidal talc with an oil and a glycol to create a suspended mixture to thereby allow the talc to be pre-wet with the oil and the glycol; admixing copolymer beads to the suspended mixture thereby allowing the beads to be pre-wet with the oil and the glycol; adding the suspended mixture to a water-based drilling fluid to form a system, the drilling fluid comprising hydrophilic clay, a pH controller, a fluid loss controller, and a dispersant; and adding the system to a well bore.
[0021] In another embodiment, the beads have an affinity for oils, esters, glycols, cellulose and olefins; the beads have a specific gravity from about 1.0 to about 1.5 and a size from about 40 microns to about 900 microns; the beads are comprised of styrene and divinylbenzene. In still another embodiment, the talc has an affinity for oils, esters, glycols, cellulose and olefins; the talc has a size range from about 2 microns to about 10 microns. In yet another embodiment, the oil consists essentially of oils, hydrocarbon oils, vegetable oils, mineral oils, paraffin oils, synthetic oils, diesel oils, animal oils and soybean oil and mixtures thereof.
[0022] In a further embodiment, the glycol consists essentially of polypropylene glycol, polyethoxylated glycol, polybutylene glycol, polyethylene glycol, propylene glycol, polyester polyol-poly(oxyethylene-oxy) propylene glycol, polyoxyalkylene glycol ethers and mixtures thereof. In yet a further embodiment, the method further comprises adding a surfactant, said surfactant comprises a polyethoxylated glycol. In still a further embodiment, the method further comprises adding a weighting agent, the weighting agent consisting essentially of barium sulfate (barite), calcium carbonate, hematite, and salts. In still yet a further embodiment, the method further comprises adding a chemical inhibitor, the chemical inhibitor consisting essentially of gypsum, lime, potassium chloride, potassium hydroxide and calcium sulfate.
[0023] In another embodiment, the pH controller consists essentially of caustic acid, potassium hydroxide, lime and sodium hydroxide; the fluid loss controller consists essentially of lignites and polyacrylamide; the hydrophilic clay consists essentially of bentonite, kaolin clay and viscosifiers; and the dispersant consists essentially of lignite and lignosulfonate.
[0024] In another further embodiment, the talc comprises from about 2% to about 50% of the additive mixture, the oil and the glycol comprises from about 10% to about 98% of the additive mixture, and the beads comprises from about 2% to about 50% of the additive mixture.
[0025] In another embodiment, the present invention relates to a water-based drilling fluid additive comprising talc and at least one carrier wherein the carrier may be oils, esters, glycols, cellulose and olefins or combinations thereof. In still another embodiment, the talc is coated or treated with the carrier converting the surface of the talc to a carrier treated or coated surface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The accompanying drawings are included to provide a further understanding of the present invention. These drawings are incorporated in and constitute a part of this specification, illustrate one or more embodiments of the present invention, and together with the description, serve to explain the principles of the present invention.
[0027] [0027]FIG. 1 is a graph representing talc particle size versus volume in percent; and
[0028] [0028]FIG. 2 is a graph representing the percent of beads suspended in oil versus the talc concentration as percent by weight of oil.
[0029] Among those benefits and improvements that have been disclosed, other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
DETAILED DESCRIPTION OF THE INVENTION
[0030] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various forms. The figures are not necessary to scale, some features may be exaggerated to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention.
[0031] The present invention provides a process that includes selecting specific materials having different particle sizes and then pre-wetting each particle with an environmentally acceptable lubricant prior to adding these particles to the water-based drilling fluid. This process produces much improved wall cake integrity and lubricity. The present invention also teaches that food grade vegetable oils are excellent carriers for various solid friction reducers and wall cake enhancers. The present invention has also discovered that pre-wetting the round copolymer beads with a food grade vegetable oil prior to adding the copolymer beads to the drilling fluid improves the lubrication or friction reducing capacity of the copolymer beads. The other criterion is that the products and its components have to be environmentally friendly.
[0032] In accordance with the manufacturing process of the present invention, talc powder is sheared with an environmentally friendly oil or liquid lubricant, which repels water. The shearing should continue until each organophilic or hydrophobic talc particle is coated with the oil or liquid lubricant. In one embodiment, the talc powder most preferred would be one with a particle size from about 1 micron to about 20 microns and one which would produce a bell shaped curve having the majority of the particles in the 2 micron to 8 micron size, as shown in FIG. 1.
[0033] The polymeric beads of the present invention should be a solid particle, preferably round and have a specific gravity close to 1.0 and have a size from about 100 microns to about 900 microns. The beads must also have an affinity for oils, esters, olefins and glycols, etc. It was determined that a copolymer bead manufactured by Dow Chemical comprised of styrene and divinylbenzene would be acceptable.
[0034] The colloidal solids of the present invention should have a size range of 2-10 microns since tests have proven that this particle size will bridge sandstone having a permeability of 200 md. The solids must also have an affinity for oils, esters, olefins and glycols, etc. In one embodiment, the solids are talc. The talc of the present invention also functions as an excellent suspending agent in both oils and glycols. FIG. 1 depicts a graphical representation of the particle size of talc and Table 1, as set forth below, represents the result statistics for the particle size for talc:
TABLE 1 Particle Size Statistics For Talc Dist. Type: Vol Concentration = 0.0136% Vol Density = 2.650 g/cub. cm Spec. SA = 0.5176 sq. m/g Mean Diameters: D (v, 0.1) = 2.40 um D (v, 0.5) = 5.28 um D (v, 0.9) = 11.68 um D [4, 3] = 6.30 um D [3, 2] = 4.37 um Span = 1.760E+00 Uniformity = 5.495E−01 Size Low (um) In % Size High (um) Under % 0.31 0.00 0.36 0.00 0.36 0.00 0.42 0.00 0.42 0.00 0.49 0.00 0.49 0.00 0.58 0.00 0.58 0.00 0.67 0.00 0.67 0.00 0.78 0.00 0.78 0.00 0.91 0.00 0.91 0.02 1.06 0.02 1.06 0.32 1.24 0.35 1.24 0.94 1.44 1.29 1.44 1.83 1.68 3.12 1.68 2.51 1.95 5.62 1.95 2.94 2.28 8.57 2.28 5.05 2.65 13.62 2.65 6.89 3.09 20.51 3.09 7.96 3.60 28.47 3.60 7.81 4.19 36.29 4.19 8.89 4.88 45.18 4.88 9.49 5.69 54.67 5.69 9.05 6.63 63.72 6.63 8.60 7.72 72.33 7.72 7.61 9.00 79.94 9.00 6.35 10.48 86.29 10.48 5.02 12.21 91.31 12.21 3.70 14.22 95.01 14.22 2.47 16.57 98.95 16.57 1.46 19.31 99.68 19.31 0.73 22.49 100.00 22.49 0.27 26.20 100.00 26.20 0.05 30.53 100.00 30.53 0.00 35.56 100.00 35.56 0.00 41.43 100.00 41.43 0.00 48.27 100.00 48.27 0.00 56.23 100.00 56.23 0.00 65.51 100.00 65.51 0.00 76.32 100.00 76.32 0.00 88.91 100.00 88.91 0.00 103.58 100.00 103.58 0.00 120.67 100.00 120.67 0.00 140.58 100.00 140.58 0.00 163.77 100.00 163.77 0.00 190.80 100.00 190.80 0.00 222.28 100.00 222.28 0.00 258.95 100.00 258.95 0.00 301.68 100.00
[0035] The carrier of the present invention may be selected from different oils, olefins, esters, fatty acids, cellulose and glycols. In another embodiment, the carrier may be synthetic oils, diesel oils, rice oils, cottonseed oils, corn oils, safalour oils, linseed oils, coconut oils, vegetable oils, mineral oils, and paraffin oils. In still another embodiment, the carrier is soybean oil. The oil coating on the hydrophobic talc particles enhances the plugging action of the talc across or into micro fractures in sands, shale and other substances down hole.
[0036] In a further embodiment, the present invention relates to a method of manufacturing a drilling fluid additive whereby talc and copolymer beads are added to soybean oil and mixed or sheared until each particle of talc and copolymer bead is oil wet. A first sample was produced by addition of 350 grams of soybean oil with 5 grams of talc and 100 grams of polymer beads to the oil, and then mixing all the components for 10 minutes using a Waring blender. After blending, the mixture was placed in a beaker for observation. The mixture appeared homogeneous and initially resembled buttermilk. After 5 minutes, the beads began to settle. After one hour, all the beads settled to the bottom of the beaker and some of the oil began separating from the mixture and clear oil was present at the upper portion of the beaker. After sitting overnight (10 hours later), the upper portion of the beaker was clear oil and the bottom portion was the talc, beads and oil. Pouring the clear oil off exposed that the beads had settled and packed tightly preventing the beads from pouring out of the beaker. This sample could not be placed in a drum or tank for shipping because the beads would settle and plug the drum or tank.
[0037] A second sample was produced by adding talc to the oil and eliminating the beads initially. It was discovered that the oil accepted approximately 40% by weight of talc. After sitting overnight, there was no separation between the talc and the oil. At that point, small additions of beads were added to the above mixture. The addition of 2% by weight of beads to the talc/oil mixture was encouraging. The beads settled slightly but did not pack off. As the concentration of the beads was increased in the mixture, it was discovered that the beads remained suspended in the mixture. FIG. 2 depicts graphical representations of the talc concentration as percent (%) by weight of oil versus the percent (%) of beads suspended in oil. FIG. 2 illustrates that as the talc concentration as a percent (%) by weight of the oil increases, the suspension qualities of the liquid oil increases. As FIG. 2 illustrates, the talc concentration of 20 percent by weight of the liquid oil suspends 100 percent of the copolymer beads.
[0038] The second sample was then heated to 150 degrees Fahrenheit for 24 hours and the copolymer beads remained suspended. The mixture was then cooled to 35 degrees Fahrenheit for 24 hours and the copolymer beads remained suspended. It was also discovered that the optimum concentration of the beads was from about 20 percent to about 30 percent by weight of the oil, and the concentration of the talc should be around 20 percent by weight of oil. Although this sample appears to be the best, the concentration may vary.
[0039] The specific examples throughout the specification will enable the present invention to be better understood. However, they are merely given by way of guidance and do not imply any limitations. Example 1 conducted tests on a 9.9 pounds per gallon (ppg) water-based drilling fluid and Example 2 conducted tests on a 16.9 pounds per gallon (ppg) water-based drilling fluid. Example 3 conducted tests on the reduction of capillary forces in both the 9.9 ppg drilling fluid of Example 1 and the 16.9 ppg drilling fluid of Example 2.
EXAMPLE 1
[0040] Test 1: Rheology & HPHT Results
[0041] In Example 1, a 9.9 pound per gallon water-based drilling fluid was tested for the (a) the compatibility of the drilling fluid-such as rheology; and the yield point and gels in particular; (b) the high pressure high temp fluid loss-HPHT; (c) the filter cake wt./gram; and (d) the filter cake thickness (in inches). Parameters were first tested on the base mud. By comparison, 2 percent (%) by volume of the oil, talc and the beads mixture was added to the base drilling fluid and mixed for 5 minutes on a waring blender. In Test 1 & Table 2, the following rheology and HPHT results were noted:
TABLE 2 Rheology & HPHT Results BASE & 2% % REDUC- BASE TALC MIXTURE TION Density 9.9 PH Meter 10.3 600 rpm 19 22 300 rpm 11 13 200 rpm 8 10 100 rpm 5 6 6 rpm 2 1 3 rpm 2 1 PV @ 120 F. 8 9 YP 3 4 Gels 10 sec/10 min 2/13 1/17 HPHT @ 200 Deg F./ml 12.0 8.0 33% Cake Wt./g 5.9 5.4 8% Cake Thickness/inch 3/32 2/32 33% MBT/pbb 30 Solid/Oil/Water 10/00/90
[0042] The results of Example 1, Test 1 indicate the following: the talc, bead and oil mixture was very compatible with the mud rheology with only slight increases in yield point and gels. The HPHT fluid loss was reduced from 12.0 to 8.0; a 33% reduction, which is excellent. The cake in weight in grams was reduced from 5.9 grams to 5.4 grams, an 8% reduction. The cake thickness in inches was reduced from 3/32 to 2/32, a 33% reduction, which is also excellent.
EXAMPLE 1
[0043] Test 2: Dynamic Filtration
[0044] In Example 1, Test 2, the following dynamic filtration criteria were tested: (a) Fluid loss versus time; (b) Filter cake wt/gram; and (c) Filter cake thickness in inches. The dynamic filtration data of Example 1, Test 2 is set forth in Table 3 below:
TABLE 3 DYNAMIC FILTRATION 5 Darcy, 50 Micron Filter Media 200 Degrees F., 600 rpm @ 1000 PSI for 60 Minutes Fluid Loss (ml) BASE & 2% TIME (Minutes) BASE TALC MIXTURE % REDUCTION Initial Spurt 1.5 trace 15 12.6 5.8 30 17.0 10.0 45 21.2 14.0 60 24.0 16.8 30% Cake Wt/g 10.7 5.8 46% Cake Thickness/Inch 3/32 2/32 33%
[0045] The results of Example 1, Test 2 are as follows: after 60 minutes, the dynamic fluid loss was reduced from 24.0 ml to 16.8 ml, a 30% reduction, which is excellent. The cake weight in grams was reduced from 10.7 grams to 5.8 grams, a 46% reduction, which is also excellent. The cake thickness was reduced from {fraction (3/32)} to {fraction (2/32)}, a 33% reduction, which is excellent.
EXAMPLE 1
[0046] Test 3: Lubricity Test
[0047] Table 4 below shows the test results of the lubricity of the additive as torque is applied.
TABLE 4 LUBRICITY TEST @ 60 rpms Co-efficient of Friction of Water (0.33-0.36) = 0.33; i.e. reading at 150 inch pounds is 33 Lubricity Reading (electric current required to sustain 60 rpm at applied torque) Applied BASE & 2% Torque/Inch Pounds BASE TALC MIXTURE % REDUCTION 100 10 11 150 16 16 200 21 21 300 31 28 400 44 37 500 66 50 600 80 65 19%
[0048] The lubricity results of Example 1, Test 3 indicate an improvement in lubrication was about 19% at the 600 reading on the lubricity tester.
EXAMPLE 1
[0049] Test 4: Texture of Dynamic Filter Cake Surfaces
[0050] The texture of the filter cake surfaces and the surfaces of the base mud were also tested. The results were as follows: the texture of the surface of the base mud was extremely smooth and shinny. The texture of the Dynamic Filter Cake Surface of the base mud treated with 2% by volume of the talc, bead and oil mixture was shinny and the copolymer beads could be seen impregnated in the cake as well as protruding on the surface of the cake.
EXAMPLE 2
[0051] Test 1: Rheology & HPHT Results
[0052] In Example 2, a 16.9 pound per gallon water-based drilling fluid was tested for the (a) the compatibility of the drilling fluid-such as rheology; and the yield point and gels in particular; (b) the high pressure high temp fluid loss-HPHT; (c) the filter cake wt./gram; and (d) the filter cake thickness (in inches). Parameters were first tested on the base mud. By comparison, 2 percent (%) by volume of the oil, talc and the beads mixture was added to the base drilling fluid and mixed for 5 minutes on a waring blender. In Example 2, Test 1, the following rheology and HPHT results were noted in Table 5 below:
TABLE 5 Rheology & HPHT Results BASE & 2% % BASE TALC MIXTURE REDUCTION Density 16.9 PH Meter 10.4 600 rpm 53 56 300 rpm 30 32 200 rpm 22 25 100 rpm 13 15 6 rpm 2 3 3 rpm 1 2 PV @ 120 F. 23 24 YP 7 8 Gels 10 sec/10 min 4/19 5/27 HPHT @ 300 Deg F./ml 15.0 13.2 12% Cake Wt./g 27.2 18.7 31% Cake Thickness/inch 6/32 4/32 33%
[0053] The results of Example 2, Test 1 indicate the following: in Test 2, Table 5, the talc, beads and oil mixture was very compatible with the mud rheology with little change points and gel. The HPHT fluid loss was reduced from 15.0 to 13.2, a 12% reduction, which is somewhat less than expected. The cake weight in grams was reduced from 27.2 grams to 18.7 grams, a 31% reduction, which is a very good result. The cake thickness was reduced from {fraction (6/32)} to {fraction (4/32)}, a 33% reduction.
EXAMPLE 2
[0054] Test 2: Dynamic Filtration
[0055] In Example 2, Test 2, the following dynamic filtration criteria were tested: (a) Fluid loss versus time; (b) Filter cake wt/gram; and (c) Filter cake thickness in inches. The dynamic filtration data of Example 2, Test 2 is set forth in Table 6 below:
TABLE 6 DYNAMIC FILTRATION 10 Darcy, 35 Micron Filter Media 300 Degrees F., 600 rpm @ 1000 PSI for 60 Minutes Fluid Loss (ml) BASE & 2% TIME (Minutes) BASE TALC MIXTURE % REDUCTION Initial Spurt 1.0 0.5 15 25.2 17.6 30 38.0 25.0 45 46.0 31.4 60 53.2 36.0 32% Cake Wt/g 91 62 32% Cake Thickness/Inch 18/32 12/32 33%
[0056] The results of Example 2, Test 2, Table 6 are as follows: after 60 minutes, the dynamic fluid loss was reduced from 24.0 ml to 16.8 ml, a 32% reduction, which is an excellent result. The cake weight in grams was reduced from 91 grams to 62 grams, a 32% reduction, which is a very good result. The filter cake was reduced from {fraction (18/32)} to {fraction (12/32)}, a 33% reduction, which is also an excellent result.
EXAMPLE 2
[0057] Test 3: Lubricity Test
[0058] Table 7 below shows the test results of the lubricity of the additive as torque is applied.
TABLE 7 LUBRICITY TEST @ 60 rpms Co-efficient of Friction of Water (0.33-0.36) = 0.33; i.e. reading at 150 inch pounds is 33 Lubricity Reading (electric current required to sustain 60 rpm at applied torque) Applied BASE & 2% Torque/Inch Pounds BASE TALC MIXTURE % REDUCTION 100 14 9 150 23 12 200 30 15 300 46 20 400 60 23 500 76 25 600 92 28 70%
[0059] The lubricity results of Example 2, Test 3 indicate an improvement in lubrication was about 70% at the 600 reading on the lubricity tester, which is an excellent result.
EXAMPLE 2
[0060] Test 4: Texture of Dynamic Filter Cake Surfaces
[0061] The texture of the filter cake surfaces and the surfaces of the base mud were also tested. The results were as follows: the texture of the surface of the base 16.9 ppg mud was smooth and shinny. The texture of the Dynamic Filter Cake surface of the base mud treated with 2% by volume of the talc, bead and oil mixture was shinny and the copolymer beads could be seen impregnated in the cake as well as protruding on the surface of the cake.
EXAMPLE 3
[0062] Reduction in Capillary Attractive Forces of Examples 1& 2
[0063] In Example 3, the (dynamic) filter cake of the base mud was placed on a flat surface and a piece of glass _inch thick and four inches square was placed flat on the surface of the base mud filter cake and allowed to sit for thirty minutes. An attempt was then made to lift the glass from the filter cake. As the glass plate was lifted, the filter cake followed and it was as though the filter cake was glued to the glass.
[0064] The (dynamic) filter cake of the base mud to which 2% of the additive of the present invention was added was placed on the flat surface and the same process discussed above was duplicated. It was found that the piece of glass easily separated from the filter cake surface, which was treated with the additive of the present invention. The results show that the additive mixture of the present invention definitely reduced, if not, eliminated the capillary attractive forces of the wall cake.
[0065] Since the above tests were conducted in open air on the counter top, it was determined that the same tests should be conducted while totally submerged in the drilling fluid. In running the same tests with the filter cake and the 4 inch piece of glass completely submerged in the drilling fluid, it would be concluded that no air would be present in the filter cake or the glass surface and such a test would resemble a wellbore filled with drilling fluid. This test results were as follows: the glass plate stuck more firmly to the submerged water-based mud wall cakes than it did in open air; and the glass plate would not stick to the wall cakes of the water-based muds, which were treated with the 2% by volume of the drilling fluid additive of the present invention.
[0066] Numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the attendant claims attached hereto, this invention may be practiced otherwise than as specifically disclosed herein. | A drilling fluid additive system is provided wherein the system is manufactured by a method comprised of admixing colloidal solids such as talc with a carrier such as oils and glycols or talc with cellulose to create a suspended mixture to thereby allow the colloidal solids to be pre-wet or coated with the carrier; and then admixing copolymer beads to the suspended mixture to allow the beads to be pre-wet or coated with the carrier; and then adding the suspended mixture with a mixture comprised of hydrophilic clay, a pH controller, a fluid loss controller, and a dispersant. | 2 |
[0001] The present application claims priority to U.S. Provisional Patent Application No. 62/010,723, entitled Personal Video Conference Lighting Assembly, filed on Jun. 11, 2014, the disclosure of which hereby is incorporated by reference as if fully restated herein.
[0002] This application incorporates by reference the disclosure of U.S. Design Patent Application No. 29/493597, entitled Personal Video Conference Lighting Assembly, filed on Jun. 11, 2014, as if fully restated herein.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The invention relates in general to a lighting assembly and, more particularly, to a lighting assembly to be used for, among other things, personal video conferencing and video streaming applications—such as, but not limited to, Internet video streaming applications.
[0005] 2. Description of Related Art
[0006] As personal computing devices—such as desk top computers, lap top computers, notebook computers, tablet computers, smart phones, as well as others—become smaller, less costly, and more powerful, their use proliferates. Many of personal computing devices are usable with external video cameras, or themselves include integrated video cameras.
[0007] Additionally, as global information networks—such as the Internet—proliferate, individuals, government organizations, and businesses increasingly are using personal computing devices for video conferencing. Video conferencing quickly is becoming a common mode of communication, as it allows participants in remote locations to meet and converse with one another as if they were present in the same room. Such video conferences may involve conversations between individuals, or conferences between groups, and may include, without limit, topics such as personal activities, commerce, academics, or telemedicine.
[0008] In any setting, proper lighting makes a tremendous difference in how people appear, and thus how they communicate, during a video conference or distance education session. Typical indoor ambient lighting—such as in an office or home setting—can be inadequate for video conferencing. Improper lighting can create harsh shadows during video conferencing, or otherwise hide or obscure the nuances of facial expression, eye-contact, or other critical aspects of non-verbal communication. Thus, proper lighting, which helps to convey these features, is important for effective communication. This is especially important, as the Internet allows speakers of different languages to interact with each other via videoconferencing applications.
[0009] Additionally, as personal computing devices become smaller and more portable, the need exists for a small, portable lighting assembly. Such an assembly allows users to engage in video conferencing easily, with effective lighting, anywhere an Internet connection is available. Moreover, given the typical proximity of the user's eyes to the video camera of a personal computing device during personal video conferencing, it is desirable that a lighting assembly would be configured to minimize eye strain or user discomfort.
SUMMARY OF THE INVENTION
[0010] Generally provided herein is a personal video conference lighting assembly that is lightweight, portable, and provides sufficient illumination to portray nuances of facial expression, eye-contact, or other critical aspects of non-verbal communication. The personal video conference lighting assembly provides lighting sufficient for a variety of personal video conferencing applications, such as personal communications, business, distance learning, and telemedicine. In a non-limiting embodiment, the personal video conference lighting assembly engages easily with a personal computing device and is easily operated by a user. Desirably, the personal video conference lighting assembly also provides high-quality illumination that minimizes eye strain and user discomfort.
[0011] Disclosed herein is a lighting assembly for use with personal computing devices. According to an embodiment, the lighting assembly includes a housing forming an interior cavity, in which a light emitting diode (LED) circuit board may be situated. At least one LED may be positioned to emit light through a front portion of the housing to illuminate the face of a user during video conferencing. Desirably, the LEDs may be configured to provide converging light that is continuous—minimizing hot spots and bands of illumination. In an embodiment, this may be accomplished through the use of optics, such as beam shaper optics. Thus, user eye strain and discomfort may be minimized. Additionally, the intensity of the light and a user's ability to control the orientation of the LED housing in certain embodiments may further contribute to user comfort during use of the lighting assembly.
[0012] In an embodiment, the housing may be connected to a neck that enables an orientation of the housing to be adjusted by the user. The neck may connect to a base unit. The base unit may have at least one support mechanism that allows the base unit to be positioned at a variety of angles. In a non-limiting embodiment, the support mechanism may include at least one rotatably-retractable leg unit. The base unit also may have a mechanism on its front portion to aid in the support of a personal computing device thereon.
[0013] In another embodiment, the neck connects the LED housing to a clipping mechanism that engages a personal computing device without a base unit. In accordance with another embodiment, the housing connects to the clipping mechanism without the use of a neck. These embodiments may allow the user to adjust the orientation of the housing without moving the personal computing device, or the housing may remain fixed with respect to the personal computing device.
[0014] Various non-limiting embodiments of the present invention enable varying degrees of ease of mobility, allowing a user to move about freely and untethered during video conferencing, while maintaining adequate and consistent light levels for enhanced camera imaging. Thus, a user may use the lighting assembly to illuminate his or her facial features during video conferencing in a manner that provides high-quality imaging, while minimizing discomfort.
[0015] These and other features and characteristics of the present invention, as well as the methods of operation and functions of the related elements of structures and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following description and the appended claims with reference to the accompanying drawings, all of which form a part of this specification, wherein like reference numerals designate corresponding parts in the various figures. As used in the specification and the claims, the singular form of “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is an exploded perspective view of an embodiment of a personal video conference lighting assembly including a base unit;
[0017] FIG. 2A is a rear view of the personal video conference lighting assembly of FIG. 1 ;
[0018] FIG. 2B is a side view of the personal video conference lighting assembly of FIG. 1 ;
[0019] FIG. 3 is an exploded perspective view of an arm clip member that may be included in the personal video conference lighting assembly of FIG. 1 ;
[0020] FIG. 4 is a front view of an LED board of the personal video conference lighting assembly;
[0021] FIG. 5A is a side view of the personal video conference lighting assembly showing a leg member in a deployed position;
[0022] FIG. 5B is a side view of the personal video conference lighting assembly according to FIG. 5A showing a leg member and leg support member in a deployed position;
[0023] FIG. 5C is a side view of the personal video conference lighting assembly according to FIG. 5A showing a leg member and leg support member in another deployed position;
[0024] FIG. 5D is a front view of the personal video conference lighting assembly of FIG. 5A ;
[0025] FIG. 6A is a front view of an embodiment of a personal video conference lighting assembly including a clipping mechanism;
[0026] FIG. 6B is a side view of the personal video conference lighting assembly according to FIG. 6A ;
[0027] FIG. 7A is a front view of an embodiment of a personal video conferencing assembly including a clipping mechanism;
[0028] FIG. 7B is a side view of the personal video conferencing assembly according to FIG. 7A ;
[0029] FIG. 8 is a front view of an embodiment of an LED housing and flexible neck;
[0030] FIG. 9A is a front view of an embodiment of a personal video conferencing assembly including a clipping mechanism, neck, and power supply housing;
[0031] FIG. 9B is a rear view of the personal video conferencing assembly including a clipping mechanism, neck, and power supply housing;
[0032] FIG. 10A is a front view of an embodiment of an LED housing;
[0033] FIG. 10B cross-sectional side view of the LED housing taken along line A-A in FIG. 10A ;
[0034] FIG. 11A is a top view of an embodiment of optics according to the present invention;
[0035] FIG. 11B is a side view of optics according to FIG. 11A ;
[0036] FIG. 11C is a bottom view of the of the optics according to FIG. 11A
[0037] FIG. 12A is a front perspective view of an embodiment of personal video conferencing assembly;
[0038] FIG. 12B is a rear perspective view of the personal video conferencing assembly according to FIG. 12A ;
[0039] FIG. 13A is a front view of an embodiment of an LED housing, depicting the emission of light, wherein optics are not included;
[0040] FIG. 13B is a front view of an embodiment of an LED housing, depicting the emission of light, wherein optics are included
[0041] FIG. 14 is a bottom view of an embodiment of an LED housing.
DETAILED DESCRIPTION OF THE INVENTION
[0042] For purposes of the description hereinafter, the spatial orientation terms and derivatives thereof shall relate to the embodiment as it is oriented in the drawing figures. However, it is to be understood that the invention may assume various alternative variations, except where expressly specified to the contrary. It is also to be understood that the specific devices illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments. Hence, specific dimensions and other physical characteristics related to the embodiments disclosed herein are not to be considered as limiting.
[0043] With reference to FIGS. 1 and 2 A- 2 B, an embodiment of lighting assembly 10 is shown that includes a base unit 40 on which a personal computing device may be placed. FIG. 2A shows a rear view of an embodiment shown in FIG. 1 . This non-limiting embodiment of lighting assembly 10 includes an LED housing 20 having a generally horizontally-elongated shape. LED housing 20 includes a front portion 21 and a back portion 22 , which may be fastened together with mechanical fasteners 24 , or other methods of fastening, such as adhesive or complimentary interlocking parts. An embodiment of LED housing 20 is shown in FIGS. 8 and 10 A- 10 B as well.
[0044] With reference to FIGS. 9B and 14 , back portion 22 of LED housing 20 may include a port 25 disposed at a substantially central portion thereof, and may be affixed to a first end 31 of neck 30 . Embodiments of neck 30 may be rigid or flexible. Embodiments of neck 30 may allow a user to adjust the orientation of LED housing 20 in order to optimize illumination of a user's face and/or other object during video conferencing. Adjustment of the angle and/or orientation of LED housing 20 also may contribute to user comfort.
[0045] With reference to FIGS. 6A and 6B , an embodiment of neck 30 may be rigid, and may be comprised of plastic, aluminum, or some other equivalent material, whereupon angle and/or orientation of LED housing 20 may be effected by pivots 26 or swivels attached to LED housing 20 and/or neck 30 . In an embodiment depicted in FIGS. 2A and 2B , a second end 32 of neck 30 may be attached to a top portion 41 of the base unit 40 . Neck 30 , LED housing 20 , and base unit 40 desirably include suitable connectors to enable first end 31 of neck 30 to connect with LED housing 20 and to enable second end 32 of neck 30 to connect with base unit 40 . Alternatively, in an embodiment, LED housing 20 may be connected to base unit 40 without neck 30 .
[0046] FIGS. 1 and 2A depict an embodiment of a power supply housing 50 . In an embodiment, power supply housing 50 may be situated in base 40 . Power supply housing 50 may be accessible through power supply housing cover 51 . In an embodiment, power supply housing cover 51 may be accessible to the user through rear portion 42 of base 40 . In an embodiment shown in FIG. 1 , at least one battery 52 may serve as a power supply for the lighting assembly 10 , and may provide power to at least one LED 61 , as shown in FIG. 4 .
[0047] In an embodiment depicted in FIGS. 2 B and 5 A- 5 D, at least one leg member 80 may be used to support assembly 10 . With reference to FIG. 2B , at least one leg member 80 may be disposed on rear portion 42 of base unit 40 in a manner that allows leg member 80 to rotatably deploy from at least one pivot point 81 , wherein one end of leg member 80 remains rotatably connected to base unit 40 by means of pins or other pivoting mechanism, not shown.
[0048] Further referencing FIGS. 1 and 2 A- 2 B, an embodiment of leg member 80 may include at least one substantially vertical member 83 . Vertical members 83 may be connected by a substantially horizontal cross member 84 . Each vertical member 83 connects to base unit 40 at a pivot point 81 . In an embodiment, leg member 80 may be U-shaped. Alternatively, base unit 40 may include at least one leg member 80 without cross member 84 . In another embodiment, multiple cross members 84 may be used. Yet another embodiment may include a configuration of vertical members 83 and at least one cross member 84 that is not U-shaped. The at least one leg member 80 may be rotatably connected to rear portion 42 of base unit 40 at pivot points 81 , and may rotate out from the base unit 40 to a set angle, or a plurality of angles.
[0049] Base unit 40 may include a ledge member 45 which, when deployed, extends outwardly from a lower area 46 of front portion 47 of base unit 40 . Ledge member 45 may be retracted into a storage position by rotating it in the direction of arrow A in FIG. 5C into a recess 92 in front portion 47 of base unit 40 , and may be held in place in said recess by pins, rods, friction fit, or other manners known in the art. In an embodiment, ledge member 45 may slidably deploy from inside base unit 40 , and may be held in position by friction forces or a locking mechanism. Ledge member 45 may be used to provide support for a personal computing device 11 , such as a tablet computer, on base unit 40 when ledge member 45 is in a deployed position.
[0050] FIGS. 1 and 5D depict embodiments of lighting assembly 10 wherein a personal computing device 11 may be supported or secured on base unit 40 by means of at least one arm clip member 70 , which may be included on the side portions 48 of base unit 40 . As more thoroughly shown in FIG. 3 , each arm clip member 70 may include a clip portion 71 , an upper arm portion 72 and a lower arm portion 73 , which constrain clip portion 71 and allow it to rotate in the direction shown by arrow B, so as to aid in securing a personal computing device to front portion 47 of the base unit 40 . In an embodiment, clip portion 71 may have rigid or semi-rigid engaged and retracted positions.
[0051] Further referencing FIG. 3 , upper arm portion 72 and lower arm portion 73 may engage each other closely, for example by means of a dovetail joint 75 . Mechanical fasteners, adhesives, or other means known in the art also may be used to engage upper arm portion 72 and lower arm portion 73 . Upper arm portion 72 and lower arm portion 73 also may be attached to each other with a bracket 76 . Bracket 76 may be comprised of galvanized steel, and may include notches 77 which engage springs, not shown, that assist in the engagement of the personal computing device by arm clip members 70 . Springs may connect notches 77 to base unit 40 or to another arm clip member 70 . Springs may aid in retraction of arm clip member 70 when they are not engaging a personal computing device 11 , and/or to aid arm clip members 70 in supporting or securing a personal computing device 11 . As depicted in FIG. 1 , in an embodiment, arm clip members 70 may horizontally slidably connect to base unit 40 , allowing arm clip members 70 to extend laterally, and for clip portion 71 to engage personal computing device 11 of various sizes. Line D in FIG. 1 depicts an embodiment of the path of lateral extension of arm clip member 70 . In another embodiment a friction member 103 , such as a foam or rubber pad, may be affixed to front portion 47 of the base unit 40 , as shown in phantom lines in FIG. 12A . Friction member 103 may assist in supporting a personal computing device 11 on base unit 40 by means of friction forces, either alone or in combination with arm clip members 70 and/or ledge member 45 .
[0052] As depicted in FIG. 1 , an embodiment of LED housing 20 may comprise a front portion 21 and back portion 22 . When engaged, front portion 21 and back portion 22 may comprise interior cavity 23 , which encloses LED circuit board 60 therein. LED housing 20 may be affixed to neck 30 by means of male and female connectors. In an embodiment, male and female connectors may include a hex nut 34 disposed in port 25 , and threaded male connector 35 disposed on first end 31 of neck 30 . Neck 30 may include a hollow portion, not shown, through which a power wire, not shown, may be run. A power wire may run between the LED housing 20 and a power supply housing 50 , and operatively connect the LED board 60 to a power supply, providing LEDs 61 with electricity. In an embodiment shown in FIG. 1 , electrical current is provided from at least one battery 52 disposed in power supply housing 50 . Other embodiments may include another power supply known in the art.
[0053] With reference to FIG. 1 , power supply housing 50 may be disposed inside base unit 40 in an embodiment. One or more batteries 52 may be disposed within power supply housing 50 , but it should be understood that various numbers or sizes of batteries 52 , or a different power supply known in the art, may be used to power LEDs 61 .
[0054] With reference to FIGS. 5A-5C , an embodiment of lighting assembly 10 may be powered from an external power source. In an embodiment, electrical power may be provided through an external cable, such as an electrical cable, USB cable, micro-USB cable, or other cable known in the art, which may be removably inserted into first connector port 105 . First connector port 105 may be operatively connected to LED circuit board 60 . Multiple connector ports—such as second connector port 106 —also may be included in lighting assembly 10 , so that power may be supplied through various types or standards of cables or connectors. One or more connector ports may be included in assembly 10 , and may be disposed, in non-limiting embodiments, on base unit 40 , or LED housing 60 . In an embodiment, a USB or similar cable connected to first connector port 105 or second connector port 106 may be used to operatively connect to personal computing device 11 . Power for lighting assembly 10 may be drawn from personal computing device 11 , which may serve as a primary or secondary power supply for assembly 10 . In an embodiment, power drawn from an external source, such as a personal computing device 11 , may be used to recharge batteries 52 disposed in power supply housing 50 . It should be understood that connector ports 105 and 106 also may be included in embodiments without base unit 40 , such as those depicted in FIGS. 9A and 9B .
[0055] With reference to FIG. 1 , base unit 40 additionally is shown to house two arm clip members 70 , as described above. Front portion 47 and rear 42 portion of base unit 40 may be attached using mechanical fasteners, adhesive, a combination of the two, or by another manner known in the art.
[0056] Lighting assembly 10 may include at least one LED 61 . FIG. 4 depicts an embodiment of an LED circuit board 60 on which is disposed a plurality of LEDs 61 . Five LEDs 61 are shown on LED circuit board 60 depicted in FIG. 4 , but it should be understood that more or fewer could be included in other embodiments. In an embodiment, LEDs 61 may be configured to emit light within the warm range on the Kelvin scale, or between 2000K-3500K. In another embodiment, LEDs 61 may be emit light at approximately 3200K. In another embodiment, LEDs 61 may emit light in the cool range of the Kelvin scale, or between 5100K-10000K. In another embodiment, LEDs 61 may emit light at approximately 5600K on the Kelvin scale. Additionally, LEDs 61 may have a +82 color rendering index.
[0057] Lighting assembly 10 also may include an input device 62 . With further reference to FIG. 4 , input device 62 may be disposed on LED circuit board 60 , and may be accessible to a user through front portion 21 of LED housing 20 . Input device 62 may control the output of power to the LEDs 61 , and may comprise a switch.
[0058] Input device 62 may be used to control a plurality of outputs of light from LEDs 61 . Multiple intensities of light output may help assembly 10 provide proper lighting to users with various skin tones, or in various levels of background light. In an embodiment, a plurality of outputs may be accomplished simply by turning on or off individual LEDs 61 on the LED circuit board 60 . A user may choose to turn on various LEDs 61 or groups of LEDs 61 by making multiple depressions of input device 62 . In a non-limiting embodiment, pressing input device 62 once may result in half of the LEDs 61 on board 60 being turned on. A second depression of input device 62 may result in the remaining LEDs 61 being turned on. Depressing input device 62 a third time may result in all LEDs 61 turning off. This may be accomplished by the use of switches, or other manners known in the art. LED circuit board 60 may include logic and a controller to control light output. In an embodiment, the output, brightness, or intensity of light emitted from LEDs 61 may be varied by using at least one resistor 102 , which may be included on an embodiment of the LED circuit board 60 , as shown in phantom lines on FIG. 4 . In an embodiment, resistor 102 is a variable resistor.
[0059] With further reference to FIGS. 5A-5C , in an embodiment, software on personal computing device 11 may be used to control LEDs 61 through a USB or other cables operatively connected to personal computing device 11 and lighting assembly 10 at first connector port 105 or second connector port 106 .
[0060] With further reference to FIG. 4 , an embodiment of LED circuit board 60 and LEDs 61 do not include adjustable pulse width modulation circuitry. In another embodiment, input device 62 turns on and off LEDs 61 without varying light output. In other embodiments, input device 62 may be disposed on base unit 40 , neck 30 , or power supply housing 50 , as depicted phantom lines in FIG. 9B .
[0061] Direct light from LEDs may cause eye strain or discomfort to users. Discomfort may be exacerbated if a user is positioned only a few feet from the LEDs 61 when they are emitting light. In an embodiment, assembly 10 is configured to illuminate a user in a manner that minimizes bright spots and light bands, and may decrease user discomfort and eye strain as well. FIG. 10B , depicts a cross section of an embodiment of LED housing 60 shown in FIG. 10A . In the non-limiting embodiment depicted in FIG. 10B , optics 63 may be positioned in front portion 21 of LED housing 20 , between a user and LEDs 61 , so that light emitted by LEDs 61 passes through optics 63 prior to reaching a user. An embodiment of optics 63 depicted in FIG. 10B includes a clearance space 69 in which LED 61 may be seated. Optics 63 may include support structure 67 , which may position optics 63 over LED 61 in a desired configuration, or such that LED-side optical surface 65 is a desired distance from LED 61 . Support structure 67 may be attached to LED board 60 by means of adhesives, or in another manner known in the art. In an embodiment at least one substantially transparent or translucent cover portion 68 may be placed holes 64 in front portion 21 of LED housing 20 between optics 63 and a user. Cover portion 68 may protect optics 63 from scratching or other damage. In an embodiment, cover portion 68 may help to shape the light emitted by LEDs 61 , as further described below.
[0062] An embodiment of optics 63 is depicted in FIGS. 11A-11C . Optics 63 may shape the light emitted by LEDs 61 . Light emitted by LED 61 enters optic 63 at an LED-side 65 , travels through optics 63 , and exits optics at observer-side surface 66 . In an embodiment, optics 63 shape or narrow the rays of light emitted by LEDs 61 , so that the beams converge on a user. FIG. 13A depicts an example of a LED housing 20 , in which light is emitted by LEDs 61 through holes 64 in front portion 21 of LED housing 20 , and wherein optics 63 are not included. FIG. 13B shows the shaping of light rays in an embodiment of the present invention wherein an embodiment of optics 63 is included between LEDs 61 and a user. Optics 63 may provide continuous light coverage over a user, while minimizing bright points or “hot spots” on the user. Optics 63 also may reduce bands of bright areas, which may occur in other configurations, such as when light emitted by LEDs 61 do not pass through optics 63 , as described above. Thus, embodiments of assembly 10 which include optics 63 may provide high-quality illumination, and may decrease eye strain and user discomfort, during video conferencing. The beam shape may be optimized by adjusting the distance of optics 63 from LEDs 61 during fabrication of assembly 10 . In an embodiment observer side surface 66 of optics 63 is positioned about six millimeters from LEDs 61 . In an embodiment seen in FIG. 10B , optics 63 may possess a clearance space 69 configured to receive an LED 61 , so that the optical medium surrounds the surface of LED 61 from which light is emitted. Optics 63 may be substantially clear, and may include a frosted finish. In a further embodiment, optics 63 are not colored diffuser lenses. Optics 63 may be comprised of polycarbonate, or other material in the art known to possess the optical qualities necessary for shaping light emitted by LEDs 61 . Optical surfaces of optics 63 may possess an optical polish. Embodiments of optics 63 may include total internal reflection (“TIR”) lenses. An embodiment of optics 63 may comprise multiple media with different optical properties, such as different indices of refraction.
[0063] With reference to FIGS. 11B-11C , embodiments of optics 63 may include a support structure 67 to aid in proper placement over LEDs 61 . A non-limiting example of optics 63 is the Carclo® model 10413 10 mm square medium frosted optic, available from Carclo Optics in Latrobe, Pa. However, it should be understood that other optics known in the art to shape beams of light to provide continuous light coverage on a user, while minimizing bright points or “hot spots” on the user, may be used as well.
[0064] In another embodiment, a user's ability to adjust the orientation of LED housing 20 , and to control the intensity of light emitted from LEDs 61 , further may contribute to user comfort and quality of illumination for video conferencing.
[0065] FIGS. 5A-5C are side views of an embodiment of assembly 10 including a leg support member 85 which may be rotatably connected to base unit 40 with pins, rods, or in some other manner, to allow it to rotate out from a pivot point 86 at one end of leg support member 85 . Leg support member 85 may connect to the base unit 40 at one or more pivot points 86 . Leg support member 85 further may rotate in the direction shown by arrow C in FIG. 5C so that, when deployed, leg support member 85 may engage leg member 80 to allow assembly 10 to support a personal computing device on base unit 40 at various, set angles. In an embodiment, leg support member 85 may include at least one notch 87 in which leg member 80 may be disposed when leg member 80 also is in a deployed position. An embodiment of the leg support member 85 depicted in FIGS. 5A-5C includes two sets of notches 87 , but it should be understood that more, or fewer notches, may be included in various embodiments of the present invention.
[0066] In another embodiment, leg member 80 requires no leg support member 85 . As seen in an embodiment depicted in FIG. 2A leg member 80 may retract rotatably into a complementary-shaped recessed area 49 in rear portion 42 of base unit 40 . FIGS. 12A-12B disclose another embodiment wherein leg member 80 may deploy from rear portion 42 of base unit 40 . In an embodiment, angle of deployment of leg member 80 may be set by friction fit, ratcheting system, or another manner known in the art.
[0067] FIGS. 6A and 6B show another embodiment of assembly 10 . Power supply housing 50 is not shown in FIG. 6B for clarity. In this embodiment, back portion 22 of the LED housing 20 is connected via pivot 26 to the neck 30 . Other embodiments may allow LED housing 20 to be rotatably connected to neck 30 as well. An embodiment of neck 30 in FIG. 6B is depicted as being rigid and adjustable in height with a thumb screw 36 . However, it should be understood that neck 30 also could be flexible as earlier described, an embodiment of which is depicted in FIG. 8 . Neck 30 attaches to a clipping mechanism 95 that engages a personal computing device. Clipping mechanism 95 may include a front portion, 37 , a back portion 38 , and a spring 39 which biases front portion 37 and back portion 38 about a pivot 91 . In an embodiment, front 37 and back 38 portions of clipping mechanism 95 may be separated about pivot 91 to engage the front and back of the personal computing device display, whereupon spring 39 biases front 37 and back 38 of clipping mechanism 95 into contact with front and back portions of a personal computing device 11 . Clipping mechanism 95 may be configured not to obscure a camera 104 integrated in the personal computing device 11 , such as a tablet computer. Power supply housing 50 may be incorporated in this embodiment substantially as described below.
[0068] FIGS. 7A and 7B depict an embodiment of lighting assembly 10 wherein LED housing 20 includes a clipping mechanism 95 without neck 30 . FIGS. 7A and 7B do not show power supply housing 50 for clarity. Front portion 37 of clipping mechanism 95 is configured not to obscure a camera 104 integrated into personal computing device 11 . Back portion 38 of clipping mechanism 95 may attach to back portion 22 of the LED housing 20 with a steel rivet, adhesive, pivot, or another manner known in the art. Power supply housing 50 may be incorporated in this embodiment substantially as described below.
[0069] In an embodiment depicted in FIGS. 9A-9B , power supply housing 50 is attached to back portion 38 of clipping mechanism 95 . Power supply housing 50 may be configured to receive at least one battery 52 , or other power supply known in the art, in order to provide electrical current to LED board 60 and LEDs 61 . Power supply housing 50 may be positioned on, or comprise, back portion 38 of clipping mechanism 95 , below LED housing 20 and neck 30 . When clipping mechanism 95 is engaged on the personal computing device, power supply housing 50 may be positioned behind the back portion of the display of the personal computing device 11 , so that power supply housing 50 does not obscure the camera or display thereof.
[0070] Although assembly 10 has been described in detail by illustrative embodiments, it is to be understood that such detail is solely for that purpose and that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover modifications and equivalent arrangements. For example, it is to be understood that the present invention contemplates that, to the extent possible, one or more features of any embodiment can be combined with one or more features of any other embodiment.
[0071] It is to be understood that the invention may assume various alternative variations, except where expressly specified to the contrary. It is also to be understood that the specific devices illustrated in the attached drawings, and described in the specification, are simply exemplary embodiments of the invention. Although the invention has been described in detail for the purpose of illustration based on what is currently considered to be the most practical and preferred embodiments, it is to be understood that such detail is solely for that purpose and that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover modifications and equivalent arrangements that are within the spirit and scope thereof. For example, it is to be understood that the present invention contemplates that, to the extent possible, one or more features of any embodiment can be combined with one or more features of any other embodiment. | A lighting assembly for use in connection with personal video conferencing includes a plurality of LEDs and can be mounted easily to a personal computing device. The lighting assembly can include a tiltable base that supports the personal computing device at various angles. The LEDs can be configured to emit converging, overlapping light that provides a continuous field of light on the user, and minimizes hot spots, bands of light, and user discomfort. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to Chinese Patent Application No. 201510135464.8 filed on Mar. 26, 2015 in the China Intellectual Property Office, the contents of which are incorporated by reference herein.
FIELD
[0002] The subject matter herein generally relates to a fingerprint identification device and a manufacturing method of the fingerprint identification device.
BACKGROUND
[0003] A fingerprint identification device can be an optical identification device, a resistive identification device, or a capacitive identification device. The capacitive identification device can include a plurality of sensor electrodes arranged on a substrate and a plurality of leads to transmit signals from the plurality of sensor electrodes. The quantity of the leads increases as higher resolution of fingerprint identification is required. Thus, when a finger touches the capacitive identification device, the leads arranged around the sensor electrodes are prone to generate signal interference.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] Implementations of the present technology will now be described, by way of example only, with reference to the attached figures.
[0005] FIG. 1 is an isometric view of a fingerprint identification device according to the present disclosure.
[0006] FIG. 2 is a cross sectional view of the fingerprint identification device of FIG. 1 taken along line II-II of FIG. 1 .
[0007] FIG. 3 is an enlarged view of circled part III of FIG. 2 .
[0008] FIG. 4 is an exploded view of the fingerprint identification device of FIG. 1 .
[0009] FIG. 5 is a flowchart of a manufacturing method of the fingerprint identification device according to the present disclosure.
DETAILED DESCRIPTION
[0010] It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein can be practiced without these specific details. In other instances, methods, procedures, and components have not been described in detail so as not to obscure the related relevant feature being described. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features. The description is not to be considered as limiting the scope of the embodiments described herein.
[0011] Several definitions that apply throughout this disclosure will now be presented.
[0012] The term “coupled” is defined as connected, whether directly or indirectly through intervening components, and is not necessarily limited to physical connections. The connection can be such that the objects are permanently connected or releasably connected. The term “comprising,” when utilized, means “including, but not necessarily limited to”; it specifically indicates open-ended inclusion or membership in the so-described combination, group, series and the like.
[0013] FIG. 1 illustrates a fingerprint identification device 10 utilizing capacitive fingerprint identification. The fingerprint identification device 10 defines a contact sensing surface 191 touchable by external objects such as a finger of a user.
[0014] FIGS. 2-4 illustrate that the fingerprint identification device 10 can include a contact protection layer 190 , a fingerprint identification sensor 100 , and a fingerprint identification controller 180 . The contact protection layer 190 covers the fingerprint identification sensor 100 to protect the fingerprint identification sensor 100 . A surface of the contact protection layer 190 is defined as the contact sensing surface 191 . The fingerprint identification sensor 100 is located on the fingerprint identification controller 180 and electrically coupled to the fingerprint identification controller 180 . When the contact sensing surface 191 is touched, the fingerprint identification sensor 100 senses fingerprint information and transmits the fingerprint information to the fingerprint identification controller 180 . The fingerprint identification controller 180 can include a plurality of interfaces 181 to receive the fingerprint data.
[0015] The contact protection layer 190 can be an anti-fingerprint (AF) film made of carbon matrix composite such as diamond-like carbon (DLC) and amorphous diamond. In the embodiment, the fingerprint identification controller 180 can be an application specific integrated circuit (ASIC).
[0016] The fingerprint identification sensor 100 can include a conductive layer 150 , a first insulating layer 140 , a plurality of sensor electrodes 120 , a substrate 110 , a plurality of leads 130 , a protection adhesive 170 , and a second insulating layer 160 .
[0017] The substrate 110 can include a top surface 111 , a bottom surface 112 opposite to the top surface 111 , and a side surface 113 coupled between the top surface 111 and the bottom surface 112 . In the embodiment, the substrate 110 can be made of strengthened glass, toughened glass, ceramic, sapphire, PET, or FPC.
[0018] The plurality of sensor electrodes 120 are arrayed on the top surface 111 . The fingerprint identification controller 180 is located below the bottom surface 112 . The plurality of leads 130 are arranged on the substrate 110 . One end of each of the plurality of leads 130 is electrically coupled to a sensor electrode 120 , and the other end of each of the plurality of leads 130 is electrically coupled to a controller interface 181 .
[0019] In detail, the one end of each of the plurality of leads 130 extends along the side surface 113 to the top surface 111 to couple with the sensor electrodes 120 , while the other end of each of the plurality of leads 130 extends along the side surface 113 to the bottom surface 112 , to couple with the controller interface 181 . The other end of each of the plurality of leads 130 can include a connecting pad 131 to couple with the controller interface 181 .
[0020] The protection adhesive 170 covers the plurality of leads 130 to fix and protect the plurality of leads 130 . In the embodiment, the protection adhesive 170 can be polymethyl methacrylate (PMMA) or epoxy resin. A thickness of the protection adhesive 170 is about 10-100 micrometers. The second insulating layer 160 covers the bottom surface 112 except for the plurality of connecting pads 131 . In the embodiment, the plurality of leads 130 can be made of indium tin oxide (ITO), silver (Ag), copper (Cu), gold (Au), or aluminium (Al).
[0021] The plurality of sensor electrodes 120 is arranged in two columns. A width of each electrode of the plurality of sensor electrodes 120 is about 20-200 micrometers. In the embodiment, the sensor electrodes 120 can be made of indium tin oxide (ITO), zinc oxide (ZnO), carbon nanotubes (CNT), silver nanowire, or grapheme.
[0022] The first insulating layer 140 covers the plurality of sensor electrodes 120 . The first insulating layer 140 and the second insulating layer 160 can be made of the same material.
[0023] The conductive layer 150 is arranged on the first insulating layer 140 . The conductive layer 150 defines a plurality of openings 151 corresponding to the plurality of sensor electrodes 120 . A size of each of the plurality of the openings 151 is larger than a size of each electrode of the plurality of sensor electrodes 120 . A gap (as shown in FIG. 3 ) D is defined from a side edge of the opening 151 to an edge of a sensor electrode 120 facing the side edge of the opening 151 . In the embodiment, a width of the gap D is 0-30 micrometers. A width of the each opening of the plurality of openings 151 is 80-260 micrometers. In the embodiment, the openings 151 are formed by yellow light etching or laser etching.
[0024] The conductive layer 150 is grounded to prevent signal interference when the finger touches the top surface 111 . The conductive layer 150 is electrically coupled to a ground pin of the controller interface 181 .
[0025] The contact protection layer 190 covers the conductive layer 150 and the plurality of sensor electrodes 120 . The protection adhesive 170 is located between the contact protection layer 190 and the second insulating layer 160 to protect the leads 130 .
[0026] A change in equivalent capacitance between a fingerprint ridge and a fingerprint valley causes a capacitance change when the contact sensing surface 191 is touched by a finger. A fingerprint ridge or fingerprint valley can be identified by the sensor electrodes 120 according to the capacitance change, thereby obtaining fingerprint data of the finger. The sensor electrodes 120 transmit the fingerprint data to the fingerprint identification controller 180 .
[0027] FIG. 5 illustrates a flowchart of the manufacturing method of the fingerprint identification device. The method is provided by way of example, as there are a variety of ways to carry out the method. Each block shown in FIG. 5 represents one or more processes, methods, or subroutines which are carried out in the example method. Furthermore, the order of blocks is illustrative only and the order of the blocks can change. Additional blocks can be added or fewer blocks may be utilized without departing from the scope of this disclosure. The example method can begin at block 401 .
[0028] At block 501 , a substrate 110 is provided. The substrate 110 can include a top surface 111 , a bottom surface 112 opposite to the top surface 111 , and a side surface 113 coupled between the top surface 111 and the bottom surface 112 .
[0029] At block 502 , a first conductive film is formed in the top surface 111 of the substrate 110 , and is patterned to form a plurality of the sensor electrodes 120 and the leads 130 . A second conductive film is formed in the bottom surface 112 of the substrate 110 and is patterned to form the plurality of connecting pads 131 . One end of each lead of the plurality of leads 130 extends along the side surface 113 to the top surface 111 , to couple with the sensor electrodes 120 . In the embodiment, the first conductive film and the second conductive film are patterned by yellow light etching or laser etching.
[0030] At block 503 , a first insulating layer 140 is formed to cover the sensor electrodes 120 and a second insulating layer 160 is formed on the bottom surface 112 . The plurality of connecting pads 131 is thus exposed.
[0031] At block 504 , a conductive layer 150 is formed on the first insulating layer 140 . In detail, a conductive material layer is deposited on the first insulating layer 140 and a plurality of openings 151 are defined to correspond to the plurality of sensor electrodes 120 . A size of each opening of the plurality of openings is larger than a size of each electrode of the plurality of sensor electrodes 120 . A gap (shown in FIG. 3 ) D is defined between the opening 151 and sensor electrode 120 . In the embodiment, a width of the gap D is 0-30 micrometers. A width of each opening of the plurality of openings 151 is 80-260 micrometers. In the embodiment, the openings 151 are formed by yellow light etching or laser etching.
[0032] At block 505 , a protection adhesive 170 is formed on the side surface 113 to cover the plurality of leads 130 . In the embodiment, the protection adhesive 170 is formed by spray or printing technology.
[0033] At block 506 , a contact protection layer 190 is formed on the conductive layer 150 .
[0034] At block 507 , the fingerprint identification controller 180 is assembled on the bottom surface 112 to couple with the plurality of connecting pads 131 .
[0035] It is to be understood that even though numerous characteristics and advantages of the present embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only; and changes may be in detail, especially in the matter of arrangement of parts within the principles of the embodiments, to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. | A fingerprint identification device includes a fingerprint identification controller and a fingerprint identification sensor. The fingerprint identification sensor includes a substrate having a top surface, a bottom surface opposite to the top surface, and a side surface coupled between the top surface and the bottom surface. Sensor electrodes are arranged on the top surface, electrical leads couple the sensor electrodes and the fingerprint identification controller. The coupling leads extend from the top surface along the side surface to the bottom surface. | 6 |
FIELD OF THE INVENTION
This invention is directed to the field of measurement and testing, and more particularly, to a novel wafer bow and warp station.
BACKGROUND OF THE INVENTION
Information representative of the degree of the bow and/or warp of semiconductor wafers is useful during many of the phases of the integrated circuit fabrication process. Bow and warp stations are called upon to provide the necessary information, and in such a way that the confidence level of the bow and warp data is not limited by the mechanical tolerances of the station. In the past, this has necessitated the provision of such precisely machined wafer receiving fixtures as optically-flat stationary platforms and precision-machined moveable platforms. As will be appreciated, such approaches not only produce costs that exponentially grow with the degree of mechanical tolerance provided but also result in comparatively-complex and/or difficult-to-use and maintain stations.
SUMMARY OF THE INVENTION
The bow and warp station of the present invention is based in the recognition that it is possible to electronically determine the mechanical fixturing induced errors and to compensate the bow and warp profile accordingly so that bow and warp data acquisition with a precision very much better than the manufacturing tolerances of the mechanical fixture of the station thereby becomes achievable.
In general terms, the present invention contemplates a measurement station having a sensor for obtaining input data representative of an intended characteristic associated with one or more identifiable locations of an object to be measured. A fixture is contemplated for supporting the object in such a way that the sensor can obtain input data representative of the intended characteristic associated with the one or more identifiable locations of the object. First signal processing means are contemplated operative in response to the input data for separating the input data into a fixture-related error component and an intended characteristic-related desired component. Second signal processing means are contemplated operative in response to the input data and to the fixture-related error component to provide output data only representative of the intended characteristic associated with the object at the one or more identifiable locations thereof.
In the preferred embodiment, the present invention discloses a wafer bow and warp station that includes a processing means operatively coupled to a capacitive sensing head and to an X, θ, and Z moveable vacuum chuck assembly. The bow and warp station is operative to obtain an X calibration and a θ calibration of the X, θ, and Z assembly fixture errors, and is operative thereafter to provide X-error and θ-error compensated bow and warp data. The capacitive sensing head is operative to provide first input data representative of the distance to the median center line of each of a plurality of identifiable right side-up locations of a wafer controllably positioned successively therein by the X, θ, and Z movable vacuum chuck assembly. The first data is stored in memory with each wafer location being uniquely identified by reference to the X and θ coordinates of the X, θ, and Z assembly relative to a home position. The capacitive sensing head is further operative to provide second data of the wafer locations of the wafer in an upside-down condition as controllably positioned therein successively by the X, θ, and Z movable vacuum chuck assembly, and the second data is stored in memory with each wafer location being uniquely identified with respect to its inverted position relative to the home position of the X, θ, and Z assembly. First signal processing means are disclosed operative in response to the first rightside-up and the second upside-down data to separate the X dependant errors for each wafer location, which is stored in memory. The capacitive sensing head is further operative to respectively provide third and fourth data representative of the distance to the median wafer centerline of each of the wafer locations of the upside-down wafer respectively relative to first and second preselected offsets in the θ coordinate defined relative to the home position of the X, θ, and Z assembly. The upside-down third and fourth data for the first and second θ-offset starting positions for each wafer location are stored in corresponding memory locations, uniquely identified with respect to the differently offset starting positions of the X, θ, and Z assembly. Second signal processing means are disclosed operative in response to the third and fourth data to separate the θ dependant errors for each wafer location, which is stored in memory. Third signal processing means are disclosed for compensating the X and the θ dependant fixture-induced errors out of the first data, and the bow/warp station of the present invention therewith provides high-confidence bow/warp output data with a tolerance not limited by the mechanical tolerances of the X, θ, and Z assembly. Since the X and θ dependant errors are repeatable run-to-run, the X and θ calibration sequence needs only be performed once. Thereafter, and for subsequent wafers high-confidence bow and warp profiles are simply obtained by compensating the measurement data for the already determined X and θ dependent fixture-induced errors. The processing means preferably includes a central control processor and a bow/warp station processor slaved to the central control processor. The first, second, third, and fourth data preferably are compiled for each measurement run by sampling wafer locations in concentric rings on outer wafer regions and by sampling selected wafer locations on inner regions of the wafer.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features and attendant advantages of the present invention will become apparent as the invention becomes better understood by referring to the following solely exemplary and non-limiting detailed description of a preferred embodiment thereof, and to the drawings, wherein:
FIG. 1 is a block diagram illustrating one exemplary system where a bow and warp station constructed in accordance with the present invention has exemplary utility;
FIG. 2 is a block diagram illustrating the bow and warp station constructed in accordance with the present invention;
FIG. 3 is a flow chart illustrating the way the dedicated bow and warp station processor executes the central control processor commands downloaded thereto of the bow and warp station constructed in accordance with the present invention;
FIG. 4 is a pictorial diagram useful in explaining the way machining tolerances introduce X and θ dependant error components of the bow and warp station constructed in accordance with the present invention;
FIG. 5 shows in FIGS. 5A through 5D thereof schematic memory diagrams useful in explaining the way the plural wafer sample locations are uniquely identified of the bow and warp station constructed in accordance with the present invention;
FIG. 6 shows a flow chart in FIGS. 6A and 6B thereof illustrating the presently preferred flow of processing of the central control processor of the bow and warp station constructed in accordance with the present invention;
FIG. 7 is a pictorial diagram useful in illustrating the presently preferred way the wafer to be profiled is sampled in outer and in inner regions thereof of the bow and warp station constructed in accordance with the present invention; and.
FIG. 8 is a flow chart illustrating the presently preferred processing sequence for normal measurement after the fixture has been calibrated.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The principles that underlie the present invention have exemplary utility as a bow/warp station to be described, but are applicable to any measurement system and situation where the measurements taken of a sample to be measured are subject to undesirable sample fixture induced measurement error components. Referring now to FIG. 1, generally designated at 10 is a block diagram illustrating one exemplary system where the bow and warp station of the present invention has exemplary utility. The system 10 includes a central control processor 12 operatively connected to an alignment station 14, a bow and warp station 16, and a sample mover 18. The sample mover 18 may, for example, be a pair of spaced rubber belts, for moving samples, such as semiconductor wafers, sequentially through the alignment station 14 and bow and warp station 16. The belts may be of the type shown and described in commonly assigned U.S. Utility patent application Ser. No. 725,159 now U.S. Pat. No. 4,722,059, incorporated herein by reference. The wafers may, for example, be loaded on the belts by automated wafer elevators, not shown, to the left of the figure. The elevators may be of the type described and claimed in commonly assigned U.S. Utility patent application Ser. No. 379,559 now abandoned as part of F.W.C. Ser. No. 851,297 now abandoned, incorporated herein by reference.
The central control processor 12 is operative to actuate the sample mover 18 to move each wafer into the alignment station 14. Although any suitable means may be employed to align the wafer, it is preferred that the wafer alignment station disclosed and claimed in commonly assigned U.S. Pat. No. 4,457,664 entitled WAFER ALIGNMENT STATION, incorporated herein by reference, be employed. The central control processor is then operative to command the alignment station to center the wafer about its centroid and selectively orient its flat or other fiducial indicia in a predetermined orientation. After the wafer is centered and oriented, the central processor is operative to command the sample mover 18 to move the centered and oriented wafer into a wafer-receiving fixture of the bow and wafer station 16. The bow and warp station 16 is then operative to compile a first data base to be described that profiles the centered and oriented wafer. The wafer is then removed from the bow and warp station 16, is flipped-over, and is positioned back into the alignment station. The central control processor then moves the centered and flipped over wafer into the bow and warp station, and it is operative to compile a second data base to be described that profiles the same points but of the centered and flipped over wafer. The processor 12 is then sequentially operative to command the bow and warp station to compile third and fourth data bases to be described each with respect to a different relative orientation of the flipped-over and centered wafer and wafer fixture. The first, second, third, and fourth data bases are selectively combined in a manner to be described to separate out fixture-related errors induced into the measurements from the desired wafer-related characteristics. The processor 12 is then operative to command the sample mover to move the wafer either to other selected wafer characterization stations or to an automated wafer elevator for unloading, both not shown, to the right of the figure. Once the fixture-related errors are determined, the measurements on subsequent wafers moved into the bow and warp station are readily profiled after compensating the measurement data for the same fixture induced errors.
Referring now to FIG. 2, generally designated at 20 is a block diagram illustrating the bow and warp station constructed in accordance with the present invention. The bow and warp station 20 includes a vacuum chuck 22 for removably holding a wafer 24 (or other sample), and a sensor generally designated 26 positioned near the chuck 22 that is operative to measure the distance to a preselected surface of any region of the wafer 24 brought into operative proximity with the sensor. The wafer 24 is of unknown, typically non-zero, bow and/or warp. The sensor 26 preferably consists of a first probe 28 designated "A", and a second spaced-apart probe 30 designated "B" defining therebetween a measuring head generally designated 32. The probes 28, 30 are preferably capacitive sensors. Probe 30 is fixably mounted to a support 34. Probe 28 is mounted in an arm 36 that is threadably fastened as at 38 for relative motion with respect to the support 34 so that the size of the head 32 can be controllably adjusted. An analog signal conditioning unit 39 designated "A+B" connected to the output of the probes 28, 30 is operative to provide an analog signal representative of the sum of the probe A and probe B outputs of successive ones of a plurality of preselected points of the wafer to be described that are successively positioned in the head 32. An analog signal conditioning unit 40 designated "A-B" connected to the output of the probes 28, 30 is operative to provide an analog signal representative of the difference of the probe A and probe B outputs of successive ones of a plurality of preselected points of the wafer to be described that are successively positioned in the head 32. As will readily be appreciated by those skilled in the art, the "A+B" output represents wafer thickness, while the "A-B" output represents distance, for example to the wafer median centerline, for each wafer location. A multiplexer 41 is coupled to the A+B and to the A-B outputs of the units 39,40. The "A+B" output is useful for flatness profiling, among other things, as disclosed and claimed in commonly assigned U.S. utility patent application Ser. No. 572,695 entitled WAFER FLATNESS STATION, incorporated herein by reference. The "A-B" output, as such, is used for bow and warp measurement and compensation to be described. An analog to digital converter 42 is connected to the output of the multiplexer 41 for providing data preferably representative of the distance to the wafer median surface of each preselected wafer location. While any suitable probes 28, 30 may be employed, it is preferred that the capacitive gauging system disclosed and claimed in commonly assigned U.S. Pat. No. 3,990,005 entitled CAPACITIVE THICKNESS GAUGING FOR UNDERGROUNDED ELEMENTS, incorporated herein by reference, be employed.
An X, θ, and Z assembly 44 is operatively connected to the vacuum chuck 22 for rotating the chuck abouts it axis θ radians, for moving the vacuum chuck along an X axis, and for moving the chuck along a Z axis. The X, θ, and Z assembly 44 is responsive to a plurality of control signals to be described to controllably manipulate the chuck to position successive ones of the preselected plurality of locations of the wafer 24 into proximity with the capacitive sensing head 32 that are preferably selected to cover the entire special extent of the wafer 24 during compilation of the first, second, third, and fourth data bases. While any suitable X, θ, and Z assembly can be employed, the X, θ, and Z assembly shown and described in the above-incorporated U.S. Patent entitled WAFER ALIGNMENT SYSTEM is presently preferred.
A dedicated bow and warp station processor 46 is connected to the analog to digital converter 42 over a data bus 48. The processor 46 is operatively connected to the X, θ, and Z assembly 44 over the data bus 48 via conventional latched drivers 50. The processor 46 has RAM 52 and PROM 54 associated therewith in the usual manner. A central control processor 56 is connected to the data bus 48 via a communication link, preferably an IEEE 488 bus 58 and an IEEE 488 interface 60. The processor 46 is slaved to the central control processor 56 and executes instructions to be described downloaded thereto by the central control processor 56 that command it to controllably rotate and translate the chuck 22 to bring the preselected wafer points that are located about the center area of the wafer and then to bring preselected points that are located surrounding the center area of the wafer into the capacitive sensing head. Concurrently therewith, the processor 46 reads the output of the A/D converter 42 for each such point and writes it into a RAM memory location via the bus 48. As appears more fully below, the address of each such location for the several data bases corresponds to the special location of the associated center or surrounding point location on the wafer as determined by the state of the X, θ, and Z assembly 44. After data collection is complete, the processor 46 sends the data back to the central control processor.
The processor 46 is operative in response to the commands downloaded thereto by the central control processor 56 to produce X, θ, Z and vacuum control signals via the data bus 48 to the drivers 50 for controlling the state of actuation of an X stepper motor, a θ stepper motor, a Z actuator, and the condition of the vacuum. In response to the X control signal, the shaft of the X stepper motor is controllably turned and rotates a worm gear the threads of which engage a threaded housing slidably mounted in linear guide rails for controlling the position of the chuck along the X axis. Likewise, the θ coordinate of the chuck is controlled by the shaft of the θ stepper motor over a belt and wheel assembly in response to the θ control signal, and the Z coordinate of the chuck is controlled by the Z actuator in response to the Z control signal. The "ON" and the "OFF" state of the vacuum applied to the vacuum chuck is controlled by a vacuum line, when "ON", the wafer is sucked-down by the chuck, and when "OFF", it is released from the chuck.
Referring now to FIG. 3, generally shown at 60 is a flow chart illustrating the operation of the slaved bow and warp station processor according to the present invention. The control processor 56 downloads commands to the CPU 46, which accepts the commands from the central processor as shown by a block 62. The bow and warp station processor 46 decodes the commands and fetches from the PROM 54 (FIG. 2) the code that specifies the corresponding X, θ, Z and vacuum actuators to move successive ones of a plurality of preselected points within the capacitive sensing head 32 (FIG. 2) as shown by a block 66, and the bow and warp station processor continues until execution of the commands are completed as shown by a block 68. For each wafer location point the processor is operative to store the corresponding value of the analog to digital converter 40 (FIG. 2) in a corresponding one of the first, second, third, and fourth data tables in RAM 42 (FIG. 2) to be described at preselected address locations thereof that respectively correspond to the position of each point of the wafer as determined by the θ motor rotary position and X motor rotary position as shown by a block 70. As shown by a block 72 after the measurements for each command to be decribed are completed, the bow and warp station processor is operative to send the data back to the control processor.
Referring now to FIG. 4, generally designated at 74 is a pictorial diagram useful in explaining the way that the X, θ and Z assembly introduces undesirable error components in the bow/warp measurements. The X drive subassembly includes a rail-guided carriage schematically illustrated at 76 that follows the threads of an X worm drive coupled to the shaft of the X stepper motor, both not shown. Ideal rails, ones that are perfectly true, are schematically illustrated by a solid line 78, and the actual guide rails, ones that are true to the extent of their mechanical and machining tolerances, are schematically illustrated by an undulatory line designated 80. The maximum change therebetween is schematically illustrated by an arrow 82 designated "D". In a practicable embodiment, the actual versus the ideal rails can vary on the order of ±0.004 inches (±101.6 microns). As will be appreciated, the actual variation therebetween locally displaces the wafer 24 in the Z direction producing an A-B error component directly proportional to the difference from the ideal rail.
The θ drive subassembly includes the θ stepper motor coupled via a belt and wheel arrangement to the chuck 22 that is journaled in bearings for θ rotation about the Z axis. The ideal spin axis is schematically illustrated by a dashed line 84, while the actual spin axes are multiple as schematically illustrated by lines 86. The differences between the actual spin axis and the ideal spin axis introduce an error in the Z position of the wafer 24 that varies with the X and θ displacement, and it is produced by such mechanical sources as non-true bearing races and wafer-to-shaft non-perpendicularity. In a practicable embodiment and for an exemplary 150 mm wafer, the Z-error at the chuck is approximately ±0.0022 inch (±56.25 microns). In accordance with the present invention, these platform induced error components are electronically determined separately as an X dependant component and as a θ dependant component. The X calibration and the θ calibration are both determined for repeatable X, θ, and Z assembly performance. The X-calibration is further determined for θ coordinate invariance and, the θ-calibration is further determined for X coordinate invariance.
X-CALIBRATION
The first measurement (M 1 ) for each wafer location to be described brought into the capacitive sensing head can be expressed as having a desired wafer related component (M w ) and an undesired fixture related component (M c ), as follows:
M.sub.1 (X, θ)=M.sub.w (X, θ)+M.sub.c (X, θ) (1)
where M 1 , M w , and M c are inatrices.
The M 1 (X, θ) data is schematically illustrated generally at 88 in FIG. 5A in a table format, and it is compiled and temporarily stored in the RAM 52 (FIG. 2) in such a way that each of the plural locations of the wafer to be bow/warp profiled to be described is assigned to a unique address location thereof determined by that (X, θ) coordinate pair that represents the corresponding X and θ position of the X, θ and Z assembly as the measurements are taken (block 70 of FIG. 3) of the corresponding locations of the wafer relative to a first predetermined X, θ, and Z "home" position. As illustrated by an arrow 90 in FIG. 5A, the M 1 data for the several wafer locations successively brought into the sensing head by the X, θ, and Z assembly are serially stored in RAM beginning within the (0,0) address location until the data table is filled.
After measurement of all of the preselected locations of the wafer is completed, the wafer is flipped-over, and brought into the bow and warp station for measurement of its flip-side relative to the first home position. The measurements (M 2 ) for each wafer location to be described brought into the capacitive sensing head of the flipped-over wafer likewise have a wafer related component (M w ) and a fixture-related component (M c ). The measurements of the same but flipped-over wafer locations can be shown to be the negative of the backward frontside measurements for the rightside-up wafer, and is expressed as follows:
M.sub.2 (X, θ)=-M.sub.w (X,-θ)+M.sub.c (X, θ) (2)
where M 2 , M w , and M c are matrices.
The M 2 data is schematically illustrated generally at 92 in FIG. 5b in a table format, and it is temporarily compiled in the RAM 52 (FIG. 2) such that each of plural wafer locations to be described successively brought into the capacitive sensing head are written into the address locations provided therefor but in reverse order as illustrated by an arrow 94 as determined by the (X, θ) coordinate pair of the X, θ and Z assembly defined relative to the same "home" position as for the front-side wafer measurements.
The M 1 and M 2 data are combinable by matrix addition to separate out the chuck-related X dependant error component (M c (X, θ)) representative of the X-fixture induced errors, as follows:
M.sub.1 +M.sub.2 =M.sub.2 (X, θ)-M.sub.w (X,-θ)+M.sub.c (X, θ)+M.sub.c (X, θ), (3)
which after cancellation and term rearrangement, becomes:
M.sub.c (X, θ)=(M.sub.1 (X, θ)+M.sub.2 (X, θ))/2. (4)
θ-CALIBRATION
After measurement of the flipped-over wafer is completed and the M 2 data table is filled, the flipped-over wafer is released by the chuck and the chuck alone is rotated a preselected number of steps (θ 1 ) in the θ direction defining a second "home" position offset from the old "home" position by the preselected θ 1 offset. The flipped-over wafer is then chucked and the same preselected locations thereof are brought into the capacitive sensing head for measurement, and as expressed in matrix format, are as follows:
M.sub.3 (X, θ)=M.sub.w (X, θ)+M.sub.c (X, θ-θ.sub.1) (5)
The M 3 data is schematically illustrated generally at 96 in FIG. 5C in a table format, and it is temporarily compiled in the RAM 52 (FIG. 2) in such a way that each wafer location to be described is stored at an associated RAM address location that represents the corresponding X and θ coordinate of the X, θ, and Z assembly as the measurements are taken (block 70 in FIG. 3) for the corresponding locations of the wafer relative to the first offset "home" position as shown by an arrow 98.
After measurements of the flipped-over wafer relative to the first "offset" home position is completed and the M 3 data table is filled, the wafer is released by the chuck and the chuck is again rotated a preselected number of steps (θ 2 ) different from θ 1 to define a third "home" position different from the second "home" position used for compiling the M 3 data table. The wafer is chucked again, and the same preselected wafer locations are brought into the capacitive sensing head for measurement relative to the third "home" position, the resulting measurements (M 4 ) being expressed as follows:
M.sub.4 (X, θ)=M.sub.w (X, θ)+M.sub.c (X, θ-θ.sub.2) (6)
The M 4 data is schematically illustrated generally at 100 in FIG. 5d in a table format, and it is temporarily compiled in the RAM 52 (FIG. 2) in such a way that each wafer location to be described is stored at an associated RAM address location that represents the corresponding X and θ position of the X, θ, and Z assembly as the measurements are taken (block 70 of FIG. 3) for the corresponding locations of the wafer relative to the third offset "home" position as shown by an arrow 102.
To separate out of the measurements the θ-dependent Z-error component, first combine equations (2) and (5) by matrix substraction as follows:
M.sub.2 (X, θ)-M.sub.3 (X, θ)=M.sub.w (X, θ)+M.sub.c (X, θ)-M.sub.w (X, θ)-M.sub.c (X, θ-θ.sub.1), (7)
By algebraic manipulation, equation (7) can be written:
i.sub.1 (θ)=M.sub.c (θ)-M.sub.c (θ-θ.sub.1), (8)
where i 1 (θ) is an intermediate variable defined as equal to the left hand side of equation (7).
Take now the fourier transform of equation (8), as follows:
I.sub.1 (ω)-W(ω)-W(ω-θ.sub.1), (9)
where I 1 (ω) is the fourier transform of i 1 (θ), W(ω) is the fourier transform of M c (θ), and where W(ω-θ 1 ) is the fourier transform of M c (θ-θ 1 ).
Equation (9) can be written as follows:
I.sub.1 (ω)=W(ω)(1-e.sup.-jθ.sbsp.1.sup.ω). (10)
Next, combine equations (2) and (6) by matrix subtraction, as follows:
M.sub.2 (X, θ)-M.sub.4 (X, θ)=M.sub.w (X, θ)+M.sub.c (X, θ)-M.sub.w (X, θ)-M.sub.c (X, θ-θ.sub.2) (11)
rearrange, and then simplify equation (11), as follows:
i.sub.2 (θ)=M.sub.c (θ)-M.sub.c (θ-θ.sub.2), (12)
where i 2 (θ) is a second intermediate variable defined to be equal to the left hand side of equation (1).
Then take the fourier transform of equation (12), as follows:
I.sub.2 (ω)=W(ω)-W(θ-θ.sub.2), (13)
where I 2 (ω) is the fourier transform of i 2 (θ), and where W(ω) and W(ω-θ 2 ) respectively are the fourier transforms of M c (θ) and M c (θ-θ 2 ).
Equation (13) can be written as:
I.sub.2 (ω)=W(ω)(1-e.sup.-jθ.sbsp.2.sup.ω) (14)
Equations (10) and (14) are then combinable by a preselected weighting function to smooth-out undesirable noise-effects. Preferably, the weighting function is in the form of a linear combination, as follows:
I.sub.3 (ω)=α(ω)I.sub.1 (ω)+β(ω)I.sub.2 (ω), (15)
where I 3 (ω) is a third variable defined to be equal to the linear combination, α(ω) is equal to |δ| 2 γ/(|γ| 2 +|δ| 2 ), β(ω) is equal to |γ| 2 δ/|γ| 2 +|δ| 2 , γ is equal to 1/(1-e -j θ.sbsp.1.sup.ω), and where δ is equal to 1/(1-e -j θ.sbsp.2.sup.ω).
The inverse fourier transform of equation (15), w 3 (X, θ), then, represents the θ dependent error component of the X, θ, and Z assembly.
In the preferred embodiment the number of steps (θ n ) of the θ motor is selected to be equal to one hundred (100) steps, and as appears below, it is important that the offsets in the θ coordinates, namely θ 1 , θ 2 , be selected to be relatively prime with each other and with θ n ; otherwise, and as will be appreciated, δ and γ blow up mathematically. In the preferred embodiment, θ 1 is selected to be equal to seventeen (17) steps and θ 2 is selected to be equal to twenty-three (23) steps.
Referring now FIG. 6, generally designated at 104 is a flow chart illustrating the operation of the central control processor of the bow and warp station constructed in accordance with the present invention. As shown by a block 106, the central control processor is operative to send a command to the alignment station 14 (FIG. 1) to align the wafer just moved into the station about its centroid and to orient its flat in space, and waits until the alignment is complete as shown by a block 108. As shown by a block 110, the central control processor is then operative to send a command to the sample mover 18 (FIG. 1) to move the aligned sample such that the centroid of the sample is positioned in the capacitive sensing head 32 (FIG. 2), and waits until the motion is complete as illustrated by a block 112. As shown by a block 114, the central control processor is then operative to send a command to the bow and warp station processor to measure the center area of the sample.
The central control processor waits until the data representative of the center area of the wafer has been received as shown by a block 116. The "measure center area of sample" command is executed by the bow and warp station processor in accordance with the instructions corresponding thereto stored in its PROM control table. As shown in FIG. 7, the bow and warp station processor is preferably operative to move the chuck from its "home" position along the X axis to a position 118 designated by a "X" intermediate the periphery of the water and the center point, and then actuates the vacuum to pick up the wafer. The processor is then operative to actuate the X stepper motor to bring the wafer center point designated by a dot 120 within the capacitive sensing head of the sensor. The processor is then operative to release the wafer, and to actuate the X, θ stepper motors to move the chuck back to its home position. The processor is then operative to pick up the wafer, and then to move three wafer points 122, 123, 124 located on an inner ring of the wafer successively within the capacitive sensing head. For each of the points 120, 122, 123, 124, the corresponding measurement is temporarily stored in RAM.
Returning now to FIG. 6, the processor is operative to store the wafer data received back from the bow and warp station processor in the appropriate M 1 data table locations (FIG. 5A) as shown by a block 126. As shown by a block 128, the central control processor is then operative to send a command to the sample mover 18 (FIG. 1) to move the sample so that the center of the sample is over the center of the vacuum chuck at its "home" position, and waits until the motion is complete as shown by a block 130. As shown by a block 132, the central control processor is then operative to send a command to the bow and warp station processor to measure the area of the wafer surrounding the center area of the wafer.
The bow and warp station processor accepts the command to measure the area surrounding the center area of the wafer downloaded thereto by the central control processor, and decodes the command and fetches from the PROM 54 (FIG. 2) the code that specifies the corresponding X, θ, Z and vacuum control signals that implement the "surrounding area measure" command. The processor is then operative to produce control signals to the X, θ, Z and vacuum actuators to move successive ones of a plurality of preselected points selected to cover the entire area of the sample surrounding the center area of the sample within the capacitive measuring head. The bow and warp station processor executes the "surrounding area measure" command in preferred embodiment as shown in FIG. 7. The area surrounding the center area of the sample is measured by successively taking a plurality of predetermined data points arrayed in concentric rings beginning with an outermost ring first and working inwardly therefrom until the innermost ring is taken. Preferably, the central control processor instructs the bow and warp station processor to do each such ring sequentially. The bow and warp station processor is operative to actuate the vacuum to pick up the wafer at its center point 134 and to actuate the X stepper motor to translate the chuck until an outermost ring 136 is positioned in the capacitive sensing head as shown in FIG. 7. The processor is then operative to actuate the θ stepper motor to successively bring a plurality of preselected points, three being specifically illustrated as "dots", located on the outermost ring 136 successively into proximity with the capacitive sensing head. The bow and warp station processor rotates the θ stepper motor taking the measurements for the complete ring. For each such ring point location the processor is operative to store the reading of the analog to digital converter 42 (FIG. 2) in the data table in RAM 52 (FIG. 2) at preselected address locations thereof that respectively correspond to the position of each such point on the ring 136 as determined by the θ motor rotary position and the X motor rotary position relative to the "home" position. Preferably, one hundred (100) steps of the θ motor are selected to cover one full rotation thereof. After the points of the outermost ring are collected in local bow and warp memory, the processor is operative to transmit the data back to the central control processor as shown by the block 72 (FIG. 3).
Returning now to FIG. 6, the central control processor waits until the data for the outermost ring is collected as shown by a block 138, and is then operative to store the received data representative of the distance of the wafer median center line of the points along the outermost ring as shown by a block 140. If the innermost ring has not yet been collected as shown by a block 142, the central control processor is operative to send a command to the bow and warp station processor to continue spinning the wafer and to move it to the next inner ring position 144 (FIG. 7) as shown by a block 145. The bow and warp control processor receives the command for the next innermost ring, and the just described process is repeated. As shown by a block 146, after the innermost ring is collected, the central control processor is operative to send a command to the bow and warp control processor to stop the spinning of the sample, to move the vacuum chuck to its nominal "home" position and drop the sample, and waits until the motion is complete as shown by a block 148.
As shown by a block 150, the central processor then stores the transmitted data sent thereto by the bow and warp station in the first data table M 1 in its associated memory.
The wafer is then flipped-over, and placed back on the sample mover, and the same steps (106-116, 126-132, 138-150) are repeated by the central processor as shown by a block 152. The data for the flipped-over wafer is the reverse of the backward frontside data, and it is stored by the same process in the second data table M 2 (FIG. 5b) in the central control processing RAM.
As shown by a block 154, the processor is then operative to send a "rotate θ 1 " command to the bow and warp station processor. The processor waits until the command is executed thereby as shown by a block 156.
After the θ assembly is preferably rotated by seventeen (17) steps, the steps described above in obtaining the M 1 and M 2 data bases are repeated, and the resulting data representative of the distance to the median center line of the wafer locations relative to the θ 1 offset "home" position are stored in the third data table M 3 (FIG. 5c) in CCP RAM as shown by a block 158.
As shown by blocks 160, 162, 164, the central control processor then obtains the fourth data table M 4 (FIG. 5d) in its RAM by repeating the same steps, but preferably with a 23 step offset in the "home" position of the θ sub-assembly.
As shown by a block 166, the CCP processor is then operative to separate the X dependant errors from the wafer-related components by means of software implementing equations (1) through (4) described above, and to separate out the θ dependant errors from the wafer-related component by means of software implementing equations (5) through (15), described above, as shown by a block 168, which are stored in memory.
As shown by a block 170, the central control processor is then operative to compensate the measurement data for the X and θ error components leaving only data representative of the wafer related component as shown by a block 170. This data can be suitably manipulated to determine, among other things, the warp and bow of the wafer as shown by a block 172. A representative computational algorithm for the warp determination is as follows: warp (X, θ)=M 1 (X, θ)-(M c (X, θ)+W 3 (X, θ)).
Referring now to FIG. 8, generally designated at 180 is a flow chart illustrating the normal measurement sequence. Wafers subsequently moved into the bow and warp station are bow and warp profiled by first obtaining the M 1 (X, θ) data as shown by a block 182, and the already determined X-calibration (M c (X, θ) and the θ-calibration (W 3 (X, θ)) fixture errors are compensated out as shown by a block 184. As shown by a block 186, the compensated measurement data can then be processed to provide the high confidence bow and warp profiles of the preferred embodiment.
Many modifications of the presently disclosed invention will become apparent to those skilled in the art without departing from the scope of the appended claims. | The present invention discloses apparatus and method for electronically determining and compensating mechanical fixture induced errors from desired object related information in a measurement system such that data acquisition is obtained with a precision very much better than the manufacturing tolerances of the mechanical fixture. In the preferred embodiment, bow and warp profiles of a semiconductor wafer are obtained with an X, θ, and Z moveable wafer-receiving chuck that have an accuracy very much better than the mechanical tolerances of the X, θ, and Z moveable chuck. The system provides for measurement of objectrelated information in plural orientations. Signal processing is disclosed for separating out of the object related information X and θ fixture induced error contributions to the data arising from mechanical tolerance of the fixture. Signal processing is disclosed for compensating bow and warp profiles of semiconductor wafers in accordance with the X and θ contributions fixture induced error are disclosed in order to provide a measurement accuracy not limited by the mechanical tolerances of the X, θ, and Z moveable wafer after receiving chuck. | 6 |
FIELD OF THE INVENTION
The present invention relates generally to improved apparatus for selectively diverting a flow of exhaust to the dump body of the truck to provide heat to a dump truck body.
BACKGROUND
A dump truck includes a dump body (or bed) for receiving material therein. Typically, the body can be raised by a hydraulic system so as eject the material from the bed at an appropriate time. Thereafter, the body can be lowered so that additional material may be loaded therein.
During certain weather conditions, the material in the body has a tendency to adhere to the contact surfaces of the body (e.g. during cold weather conditions) thereby resisting ejection of the material from the bed. To overcome this problem, it is known to provide a duct system within the body for receiving a flow of exhaust generated by the truck engine so that the flow of exhaust may be passed through the body, thereby heating the contact surfaces. Examples of such heated-body systems are disclosed in U.S. Pat. No. 2,974,997 by Parsely et al, and U.S. Pat. No. 5,797,656 by Kauk et al, the disclosures of both of which are incorporated herein by reference, to the extent not inconsistent herewith. By providing heat to the body in the aforesaid manner, the tendency of the material to adhere to the contact surfaces of the body during freezing weather is reduced.
Recently, stricter environmental regulations have been passed. The new regulations will require enhanced filtering of particulates via a Diesel Particulate Filter (DPF). The DPF traps particulates with a filter. When the filter becomes full, an additional burner activates to burn off the particulates at a higher temperature than that of the exhaust under normal operating conditions.
When the DPF activates (known as the “regeneration” cycle, or “regen” for short), then the exhaust gas increases from the normal 500-900 degrees Fahrenheit to as high as 1100 degrees Fahrenheit. This temperature can weaken or damage an aluminum dump body. It can also damage the paint on a steel dump body.
Attempts to address this problem have included a plastic liner to line the dump body. In practice, this has limited effectiveness, since material may undesirably adhere to the plastic liner under certain conditions. An alternative attempt to address this issue includes a separate fuel-powered heater to heat the dump body. This has the disadvantage of extra weight and complexity for an additional heat-generating system, as well requiring additional fuel for supplying the additional heat-generating system. Therefore, what is needed is the ability to heat the dump body of a truck having a diesel particulate filter, without the aforementioned disadvantages.
SUMMARY OF THE INVENTION
The present invention provides a system for providing heat to the dump body of a dump truck. The system of the present invention is suitable for use with truck equipped with a diesel particulate filter. When enabled, the system controls the exit path of exhaust gas such that it is routed to the body dump body during normal operating conditions. In one embodiment, when the diesel particulate filter enters a regeneration cycle, high heat is produced. The system then routes the exhaust gas as to bypass the dump body to avoid heat damage from the higher temperature exhaust gas. In another embodiment, the system partially diverts the exhaust gas, such that a portion of the exhaust gas enters the dump body during the regeneration cycle of the diesel particulate filter, providing heat to the dump body during the regeneration cycle, yet restricting the flow of exhaust gas, thereby preventing damage to the dump body.
The present invention further provides a system for providing heat to the dump body of a dump truck using exhaust, comprising a diesel engine, an exhaust stack having a venting end, and a diesel particulate filter, the exhaust gas of said diesel engine routed to the input of the diesel particulate filter, the exhaust output from the diesel particulate filter routed to an exhaust temperature control module, the exhaust temperature control module having temperature sensing means, and exhaust diverting means, whereby the exhaust gas is diverted to the dump body when the exhaust gas is at or below a predetermined threshold, and the exhaust gas bypasses the dump body when the exhaust gas exceeds a predetermined threshold.
The present invention further provides an exhaust diverting means that comprises:
an air cylinder, said air cylinder connected to an extension member; an air supply conduit connected to the air cylinder; an air flow controller disposed inline with said air supply conduit; a temperature sensor, the temperature sensor disposed to provide a temperature signal to the air flow controller; a diverter control arm having a first and second end; the first end of the diverter control arm connected to the extension member; and the second end of the diverter control arm connected to a diverter; whereby the temperature signal causes activation of the air cylinder, moving the extension member, thereby moving the diverter control arm, and establishing the position of the diverter.
The present invention further provides an operator control, whereby the operator control is disposed to disable and enable the air flow controller, thereby providing the truck operator with the capability to disable the system.
The present invention further provides an operator control comprising a temperature selection control, whereby a predetermined threshold temperature of the air flow controller is adjustable by the operator.
The present invention further provides an operator control comprising a temperature selection control having a lower selectable limit of about 650 degrees Fahrenheit, and an upper selectable limit of about 800 degrees Fahrenheit.
The present invention further provides a system comprising:
a second air flow controller disposed inline with said air supply conduit; and a second temperature sensor, the temperature sensor disposed to provide a temperature signal to the second air flow controller. This provides an additional margin of safety.
The present invention further provides a system comprising an exhaust diverting means comprising:
an electrically actuated magnetic control cylinder, the cylinder connected to an extension member; an electric supply conduit connected to the cylinder; a switch disposed inline with the electric supply conduit; a temperature sensor, the temperature sensor disposed to provide a temperature signal to the switch; a diverter control arm having a first and second end; the first end of the diverter control arm connected to the extension member; and the second end of the diverter control arm connected to a diverter; whereby the temperature signal causes activation of the electrically actuated magnetic control cylinder, moving the extension member, thereby moving the diverter control arm, and establishing the position of the diverter.
The present invention further provides a system comprising an exhaust diverting means that comprises a heat sensitive coil spring actuator disposed to control the position of a diverter, whereby the heat sensitive coil spring actuator is configured to actuate at a predetermined temperature, thereby establishing the exit path of the exhaust gas.
The present invention further provides a system wherein the exhaust temperature control module is mounted to the venting end of the exhaust stack.
The present invention further provides a system for providing heat to the dump body of a dump truck using exhaust, comprising a diesel engine, an exhaust stack having a venting end, and a diesel particulate filter, the exhaust gas of the diesel engine routed to the input of the diesel particulate filter, the exhaust output from the diesel particulate filter routed to an exhaust temperature control module, the exhaust temperature control module having temperature sensing means, and exhaust diverting means, whereby the exhaust gas is diverted to the dump body when the exhaust gas is at or below a predetermined threshold, and the exhaust gas bypasses the dump body when the exhaust gas exceeds a predetermined threshold, wherein the exhaust diverting means comprises:
an air cylinder, the air cylinder connected to an extension member; an air supply conduit connected to the air cylinder; at least one air flow controller disposed inline with the air supply conduit; at least one temperature sensor, each of the temperature sensors disposed to provide a temperature signal to a corresponding air flow controller; a diverter control arm having a first and second end; the first end of said diverter control arm connected to the extension member; and the second end of the diverter control arm connected to a diverter; whereby the temperature signals cause activation of the air cylinder, moving the extension member, thereby moving the diverter control arm, and establishing the position of the diverter. If any one of the temperature signals indicates that the temperature exceeds a predetermined threshold, then the air cylinder is deactivated, and exhaust gas bypasses the dump body. This provides an additional margin of safety.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a prior art dump truck, identifying the dump body and exhaust stack.
FIG. 2 shows a block diagram of an exhaust system that utilizes the present invention.
FIGS. 3A and 3B show additional details of an embodiment of the exhaust temperature control module of the present invention.
FIGS. 3C and 3D show additional details of alternative embodiments of the exhaust temperature control module of the present invention.
FIG. 4 shows another alternative embodiment of the exhaust temperature control module of the present invention.
FIG. 5 shows a dump truck equipped with the exhaust temperature control module of the present invention.
DETAILED DESCRIPTION
FIG. 1 shows a prior art dump truck 100 , having a dump body 104 , and an exhaust stack 108 . In this prior art dump truck, exhaust gas will either exit via exhaust stack 108 , or pass through the dump body 104 , depending on whether the dump body is in a horizontal or tilted orientation. This system works satisfactorily when no DPF is present. However, with a DPF, the exhaust gas is too hot to safely enter the truck body 104 during the DPF regen cycle. The present invention addresses this problem.
FIG. 2 shows a block diagram of an exhaust system 200 that utilizes the present invention. In this case, a diesel engine 204 outputs exhaust gas via conduit 206 to a DPF 208 . The exhaust gas of the DPF 208 is output via conduit 210 to the exhaust temperature control module (ETC) 212 of the present invention. Exhaust gas is output from the ETC 212 via conduit 222 , which leads to the exhaust stack of the dump truck (in which case the exhaust gas bypasses the dump body), or via conduit 226 , which leads to the dump body of the dump truck. Hence, ETC 212 establishes the exit path of the exhaust gas. In some operating modes, the exhaust gas may be output via both conduit 222 and conduit 226 simultaneously, in varying amounts, to maintain a desired temperature range of exhaust gas output to conduit 226 . Other elements that are not depicted in this block diagram, but may be present, include muffler devices, and other pollution control devices, such as catalytic converters, as is well known in the art.
FIG. 3A shows additional detail of an embodiment of the exhaust temperature control module 212 of the present invention. In this embodiment, exhaust gas travels from the engine 204 via conduit 206 , and enters DPF 208 . The exhaust gas exits DPF 208 via conduit 210 , and enters ETC module 212 . Within ETC module 212 , exhaust may be routed to conduit 322 , which leads to the exhaust stack (e.g. 108 of FIG. 1 ), or routed to conduit 326 , which leads to the dump body (e.g. 104 of FIG. 1 ) to provide heat to the dump body. An air cylinder 304 moves extension member 312 when supplied with air. Extension member 312 is connected to diverter control arm 316 . Diverter control arm 316 is attached to pivot joint 320 . Inside the exhaust pipe 323 , diverter 336 is connected to diverter control arm 316 . As shown in FIG. 3A , the air cylinder is biased such that when no compressed air source is fed into air cylinder 304 , all exhaust gas is routed via conduit 322 , and is sent to the exhaust stack. Compressed air is supplied to air cylinder 304 via air supply conduit 309 . The flow of compressed air to air supply conduit 309 is controlled by air flow controller 308 , which is disposed inline with air supply conduit 309 . Air flow controller 308 provides compressed air to air cylinder 304 upon detecting a safe temperature from temperature sensor 328 . Temperature sensor 328 provides a temperature signal via signal path 332 . The temperature sensing means may be implemented by a variety of technologies, including, but not limited to, thermocouples, thermistors, RTD (resistance temperature detectors), and thermal imaging devices. In one embodiment of the present invention, the temperature signal provided by temperature sensor 328 is a binary signal that indicates if a predetermined temperature threshold is exceeded. In another embodiment of the present invention, the temperature signal is an analog signal whose voltage varies in a predetermined relationship to temperature. In yet another embodiment of the present invention, the temperature signal is a digital communication signal, providing temperature values in packets or a data stream that is received by air flow controller 308 . Air flow controller may also be configured to restrict compressed air flow via operator control 343 . Operator control 343 is preferably located within the cab of the truck. In this way, an operator can disable the dump body heat when the conditions do not require it. This may be the case when the ambient temperature is above freezing, when the dump body is raised, or when the dump body is empty. Operator control 343 may optionally provide a temperature selection control for adjustment of the predetermined threshold temperature for diverting the exhaust gas to the dump body. For example, the control may provide for adjusting the threshold temperature in a range from 650 degrees Fahrenheit to 800 degrees Fahrenheit.
As shown in FIG. 3B , when air cylinder 304 is supplied with compressed air, it causes extension member 312 to extend. This causes diverter 336 to move to a position that directs the majority of the exhaust gas to conduit 326 , which supplies the exhaust gas to the dump body, thereby providing heat to the dump body. When the DPF 208 initiates a regen cycle, the exhaust gas will rise from approximately 500-900 degrees Fahrenheit to approximately 1,100 degrees Fahrenheit. The air flow controller 308 is preferably configured to stop the flow of compressed air when the exhaust gas temperature at the temperature sensor 328 exceeds about 700 degrees Fahrenheit, thereby diverting exhaust gas via conduit 322 to the exhaust stack (as shown in FIG. 3A ). This ensures that the dump body, which is usually aluminum or steel, is not subject to excessive heat.
In one embodiment, it is contemplated that the flow controller will either route exhaust gas to the exhaust stack (via conduit 322 ), or route exhaust gas to the dump body (via conduit 326 ). However, it is also contemplated that an embodiment may provide more precise temperature control via a variable positioning of the diverter 336 , such that a portion of the exhaust gas is allowed to flow through conduit 322 , and a portion is simultaneously allowed to flow through conduit 326 , thereby allowing for more precise control of the exhaust gas entering the dump body.
FIG. 3C shows an alternative embodiment of the exhaust temperature control module 212 of the present invention. In this embodiment, an electrically actuated magnetic control cylinder 404 is used in place of an air cylinder. In this embodiment, the electric supply to cylinder 404 is delivered via electric conduit 409 , and is controlled by switch 408 . Switch 408 provides electric current to cylinder 404 upon detecting a safe temperature from temperature sensor 328 .
FIG. 3D shows an alternative embodiment of the exhaust temperature control module 212 of the present invention. In this embodiment, heat sensitive coil spring actuator 446 controls the diverter 336 . When the temperature of actuator 446 exceeds a predetermined level, the diverter 336 moves to block conduit 326 , and allows exhaust to vent to the exhaust stack via conduit 322 .
FIG. 4 shows an alternative embodiment of the exhaust temperature control module 212 of the present invention. In this embodiment, two temperature sensors ( 328 A, 328 B) are used. Temperature sensor 328 A provides a temperature signal via signal path 322 A to air flow controller 308 A. Temperature sensor 328 B provides a temperature signal via signal path 332 B to air flow controller 308 B. In this arrangement, an extra margin of safety is provided by having air flow controllers 308 A and 308 B in series, each controlled with independent temperature sensors ( 328 A and 328 B) and signal paths ( 332 A and 332 B). If either one of the air flow controllers ( 308 A, 308 B) stops the flow of compressed air to air cylinders 304 , the exhaust gas will be diverted to the exhaust stack via conduit 332 . In this way, if one temperature sensor or signal path fails, the redundancy of multiple temperature sensors and signal paths allows for the exhaust gas to be diverted via conduit 332 to the exhaust stack, thereby preventing excessively hot exhaust gas from entering the dump body.
FIG. 5 shows a dump truck 500 equipped with the exhaust temperature control module 512 of the present invention, and a DPF (not shown). In this embodiment, an exhaust temperature control module (ETC) 512 (similar to the ETC 212 described previously) is adapted to mount to the venting end of exhaust stack 108 . Electrical and compressed air supplies (not shown) are also provided to ETC 512 . When the ETC is operating in a mode to provide heat to the dump body 104 , it routes exhaust gas via conduit 526 . When the ETC is operating in a mode to prevent exhaust gas from entering the dump body 104 , it routes exhaust gas to the atmosphere via conduit 522 . In this way, the present invention can be adapted to a dump truck with no modification to the exhaust system prior to the point where the exhaust would be output to the atmosphere.
Although the descriptions above contain many specific details, these should not be construed as limiting the scope of the invention, but merely as providing illustrations of some of the presently preferred embodiments of this invention. For example, exhaust gas diverting mechanisms may be used, such as an electrically actuated magnetic control cylinder, or a heat sensitive coil spring actuating the diverter. Various types of signaling arrangements can be used in addition to, or instead of monitoring the temperature, such as monitoring a DPF activation signal directly from the DPF device or the engine. Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given. | A system for providing heat to the dump body of a dump truck is disclosed. The disclosed system is suitable for use with truck equipped with a diesel particulate filter. When enabled, the system controls the exit path of exhaust gas such that it is routed to the dump body during normal operating conditions. In one embodiment, when the diesel particulate filter enters a regeneration cycle, high heat is produced. The system then routes the exhaust gas as to bypass the dump body to avoid heat damage from the higher temperature exhaust gas. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a water-absorbent cellulosic/acrylic spunlaced fabric having improved wickability and water retention capabilities, composite water-absorbent sheet materials and articles made therefrom, and the use of such materials and articles to protect other materials from damage by water and aqueous soiling, especially such as hospital bedding.
2. Description of the Related Art
Water-absorbent spunlaced fabrics of synthetic acrylic and cellulosic fibers, and a method for their manufacture, are known for use in reusable diapers as taught, for example, in U.S. Pat. No. 3,485,709 (Evans). Absorbent spunlaced fabrics, and their manufacture, of acrylic and polyester fibers useful as wipers, coverstock for sanitary napkins, diapers, and the like are known as taught, for example, in U.S. Pat. No. 5,093,190 (Kwok et al.). Reusable, washable, multilayered urine-absorbent, bed pads having a soft pervious outer sheet, and an impermeable outer sheet, with a non-woven layer of absorbent material, such as a mixture of rayon and polyester fibers, in between is known from U.S. Pat. No. 4,664,959 (Dagenais et al.). Another reusable incontinent underpad is the subject of U.S. Pat. No. 5,085,653 (Levy) comprising a pervious woven or knit fabric layer, a nonwoven absorbent layer and an impervious film layer. The absorbent layer can be a blend of polyester, rayon, or 100% polyester, rayon, or cotton.
Improvements in the wickability and liquid retention capabilities of absorbent fabrics for such applications continue to be sought in an effort to provide more effective protection and comfort in use. This is especially true concerning reusable hospital bed pads for incontinent adult patients, where the weight of the patient tends to cause pooling of the urine beneath the patient, which is not readily wicked away by presently used bed pads. Present pads, for example, may consist of a woven polyester/cotton top layer, an internal absorbent layer of polyester or polyester/rayon in a nonwoven fabric, a urethane or vinyl waterproof bottom sheet to which is bonded a knit polyester or nylon fabric to provide a non-slip surface on the bed, as taught in U.S. Pat. No. 5,085,653 (Levy).
SUMMARY OF THE INVENTION
This invention provides an improved spunlaced water-absorbent fabric comprised of a mixture of acrylic and synthetic cellulosic fibers wherein the improved fabric consists essentially of about 25 but less than 50 percent, by weight, of crimped acrylic fibers having a denier per filament (dpf) of about 0.75 to about 3.0 and a length from about 0.75 to about 3.0 inches and complementally about 75 to more than 50 percent of crimped, synthetic, hydrophilic cellulosic fibers having a dpf of from about 0.75 to about 3.0 and a length from about 0.75 to about 3.0 inches.
More preferably, for best water-wicking and retention properties and desired fabric bulk the fabric consists essentially of 30 to 40% of the acrylic fibers and correspondingly 70 to 60% of the cellulosic fibers and has a basis weight of 3.0 to 5.0 oz/yd 2 . For best performance, the cellulosic fibers consist essentially of solvent spun unmodified cellulose, as opposed to those made using regenerated xanthated cellulose, commonly known as viscose rayon. The "unmodified" cellulosic fibers are preferably of substantially round cross-section to achieve the best overall performance of wicking and bulk.
Such fabrics have been found to provide an outstanding combination of absorbent properties including high wick rates and essentially quantitative liquid retention as compared to similar combinations of cellulosic and polyethylene terephthalate fibers, and fabrics of 100% of the same cellulosic fibers. The fabric preferably is sufficiently entangled to provide integrity through wash cycling in normal use. This can be achieved while minimizing the loss of fabric thickness by using wider spaced jets in the manufacturing process at lower pressure.
Both the synthetic hydrophilic cellulosic fibers and the acrylic fibers are preferably of substantially round cross-section for the best wicking and retention performance, although non-round fibers, such as those having a known crenulated cross-section can be used.
DETAILED DESCRIPTION OF THE INVENTION
The acrylic fibers of this invention are comprised of polymers and copolymers of polyacrylonitrile, such as available commercially under the trademarks such as "Orlon", "Creslan" and "Acrilan".
The cellulosic fibers can be any hydrophilic, synthetic cellulose-based fiber such as viscose rayon but preferably are of solvent spun cellulose such as "lyocel" sold by Courtaulds Corporation.
For use in hospital bed pads for incontinent patients it is preferred that the acrylic fibers in the absorbent fabric contain a biocide, for example, one commercially known as "Microban", which can be introduced in the acrylic polymer solution during spinning. Biocide-containing acrylic fibers are commercially available, for example, "Biocryl" from the Mann Industrial Company. For use in hospital applications such as in bed pads, it is preferred that a biocide, or antimicrobial agent, be used that kills MRSA bacteria, i.e., methicillin resistant Staphyloccocus aureus.
The absorbent spunlaced fabrics of this invention can be prepared by methods known in the art as taught, for example, in U.S. Pat. No. 3,485,709 (Evans) and 5,093,190 (Kwok et al.), mentioned above, the entire disclosures of which are incorporated herein by way of reference.
Useful, but non-limiting, absorbent articles which can incorporate the absorbent fabric of this invention can be constructed as described for example in U.S. Pat. Nos. 5,085,653 (Levy) and 4,664,959 (Dagenais et al.), the entire disclosures of which are incorporated herein by way of reference. Other applications include protective absorbent sheet, bandage, and garment structures incorporating the subject absorbent fabrics and other uses of highly absorbent synthetic fabrics as already known in the art.
Typically, a 4.0 oz/yd 2 fabric of the invention is made at 13 YPM windup speed to give a 5.4 lbs/in/hr rate of production. The jet profile is optimized for that throughput and can be adjusted as the speed or basis weight are changed. Important features of the jet profile are preferably the use of 7 mil jets spaced at 10 per inch to provide the first effective needling (in consolidation) and their use in the "power" positions to effect most of the real entanglement (this provides bulk and integrity which can be hard to get with smaller bore jets and more closely spaced jets.) Typical needling jet profiles for hydroentangling the absorbent layers of this invention on conventional apparatus are shown in Table I.
TABLE I______________________________________ PRES- JET SIZE HOLES/INCH SUREPOSITION NO. MILS NO. PSIG______________________________________CONSOLIDATOR 1 7 10 800CONSOLIDATOR 2 7 10 750WASHERBELT 1 5 40 400WASHERBELT 2 5 40 600WASHERBELT 3 5 40 800WASHERBELT 4 5 40 OFFWASHERBELT 5 7 10 1800WASHERBELT 6 7 10 1800DRUMWASHER 1 5 40 400DRUMWASHER 2 5 40 600DRUMWASHER 3 5 40 800DRUMWASHER 4 5 40 0FFDRUMWASHER 5 7 10 1800DRUMWASHER 6 7 10 1200______________________________________
Each of the 7/10 jets provides 0.30 horsepower hour-pounds force per pound of fabric (vs. 0.20 for "stable fabric") and at 1" of jet distance is in excess of 1 MM poundals per square inch second energy flux, using the calculations shown by Kwok in U.S. Pat. No. 5,093,190.
______________________________________WASHER IMPACT TIMES ENERGY(IXE) AND JET FLOW CALCULATION______________________________________BASIS WT. 4.00 OZ/YD.sup.2 LINE SPEED 13 YDS/MINPIH 5.42 JET LENGTH 57 IN(LBS/IN-HR) LINE 4______________________________________BELT WASHERPOSITION DIAMETER TYPE PRESSURE IXE GPM______________________________________1 5 40 400 0.15 202 5 40 600 0.41 253 5 40 800 0.84 284 5 40 0 0.00 05 7 10 1800 6.09 216 7 10 1800 6.09 21TOTALS 13.57 115______________________________________DRUM WASHER1 5 40 400 0.15 202 5 40 600 0.41 253 5 40 800 0.84 284 5 40 0 0.00 05 7 10 1800 6.09 216 7 10 1200 2.21 17TOTALS 9.69 111______________________________________OTHER JETSCONS. 7 10 800 -- 14NO.CONS. 7 10 750 -- 13NO.TOTAL IXE = 23TOTAL FLOW = 253______________________________________
DESCRIPTION OF TEST METHODS USED
The Absorbent Capacity is the numerical average of the GATS absorbency and the intrinsic absorbency reported as a percent. These measurements are averaged to get a number for a "partially loaded" fabric since the intrinsic absorbency is not under a load and the GATS uses about 350 kg per square meter loading.
The 80% Absorbency Challenge method uses 80% of the absorbency reported to challenge the fabric with artificial urine at 100° F. and then see how much is lost on vertical suspension for one minute.
Wick Rate is measured by the INDA STM 10.1 method.
Heat Loss is the cooling rate in °F. on challenging the bedpads with 80% of their capacity in artificial urine at 100° F.
Details are as follows:
GRAVIMETRIC ABSORBENCY TESTER (GATS), % ABS.
Equipment: Gravimetric Absorbency Tester from M&K systems or equivalent. Die of 2" diameter and a 2" diameter weight of 712 grams, flat on the bottom.
Procedure: Cut out four 2" diameter samples from product. Allow the samples to condition in the lab at 72° F. and 50% RH a minimum of 4 hours. Weigh the samples to the nearest 0.001 gram and record.
Set up GATS apparatus and set range to 20 g and print point to 0.02 g.
After pressing "yes" to start, place the sample and weight on the plate above the single orifice at the same time, allow to run until weight loss on the balance stops, usually less than 1 minute and 30 seconds.
Calc.: 100×GATS weight/sample weight=% ABS.
INTRINSIC ABSORBENCE
Cut out 2 strips of product 1"×8" each. Measure 3.5" from each end of strip and mark on opposite sides. Cut strip going from mark to mark. This will give two samples per strip that are 4.5" long measured to the point.
Weigh each sample to the nearest 0.0001 gram. Suspend the sample at the farthest corner from the acute point and immerse in water. (Water should be at room temperature, about 72° F.) Allow to soak for 1 minute, remove and allow to drain for a minute. Immediately weigh to nearest 0.0001 gram and record.
Calc.: 100×(grams wet--grams dry)/grams dry=% ABS. Take an average of 4 results minimum.
LIOUID RETENTION TESTING (80% CHALLENGE TEST)
Equipment: 400 ml beaker, 100 ml burette, 125 ml separatory funnel, thermometer referenced to NBS, lab stands, burette holder, ring holder ( for separatory funnel), 6" watch glasses, 90° clamp and 12" rod, stopwatch or lab timer, blotter paper cut into 5.75" circles.
Reagent: Artificial urine.
Procedure: Set up first ring stand with burette holder near top and ring holder near bottom so that the separatory funnel is 1" above the base and the burette drains into the funnel. Set up the second ring stand beside the first with a rod parallel to and about 12" above its base. Place a watch glass centering under the separatory funnel and under the horizontal bar. Set up a stopwatch or timer close by.
The product to be tested should have been washed at least twice. Cut 6" square samples from the bedpad, 5 per item and weigh; use the average weight to calculate the challenge. [(Int. ABS+GATS ABS)/200]×0.80×avg. weight=ml challenge. Weigh the blotter paper disk to 0.01 gram and place in the watch glass under the horizontal bar. (Note: Up to three of the disks may be needed, depending upon liquid not retained.)
Heat artificial urine in the 400 ml beaker to 42° C. Fill the burette with it and deliver the calculated ml challenge to the separatory funnel. Place the thermometer into the separatory funnel. When the temperature drops to 38° C. drop the liquid onto a sample fabric and start timer; drop time should be less than 1 minute.
After 2 minutes elapsed time hang the sample by one corner over the blotter disk. Small binder clips can be used to do this. Suspend for 1 minute then quickly remove. Weigh the blotter. Calculate the weight lost to the blotter. [(wet weight--dry weight)/ml delivered]×100=% loss.
WICKING RATE METHOD (FROM INDA STM)
Apparatus: Glass beaker--250 ml capacity, indelible pencil, ruler, stopwatch.
Test Specimens: Cut 3 strips 25 mm (1 in.) wide and 100-150 mm (4-6 in.) long with the long dimension in the machine direction. Cut an additional 3 specimens with the long direction in the cross direction. Mark each strip with an indelible pencil 3 nun (1/8 in.) and 28.4 mm (11/8 in.) from one end.
Procedure: Clamp the strips at the unmarked end so that they hang vertically. Lower the strips into the beaker containing approximately 100 ml of distilled water at 21±1.1° C. (70°±2° F.) immersing them to the 3 mm (1/8 in.) mark. With a stopwatch record the time for the water to rise 25.4 mm (1 in.). Alternatively measure the height in millimeters to which the water rises in 5 minutes.
Calculation and Report: Average the results of 3 tests in each direction and report the results for each.
HEAT LOSS TEST
Purpose of Test: Determine the rate at which a given liquid will dissipate heat over a period of time from sample fabrics.
Equipment: Minolta/Land Cyclops, Compac 3 IR Thermometer and compatible data logger or comparable. An NBS 160° referenced thermometer, 100 ml burette, 100 ml beakers, 400 ml beakers, 6" diameter watch glasses, 14"×14"×1" styrofoam block, a 32" wide×24" deep×12" high board enclosure open on the top and from (to cut down drafts).
Reagents: Artificial urine.
Procedure: Ensure product samples have been through at least 2 wash cycles. Cut out the samples as 5.75" diameter circles and allow to condition in the lab at 72° F. and 50% RH for at least 4 hours. Weigh 5 samples to the nearest 0.01 gram and average the weight. Use this average as a base for the determination of 80% of the fabrics capacity as follows: [(Int. ABS+GATS ABS)/200]×0.80×average weight=ml where ml is the milliliters of artificial urine to be used.
Heat artificial urine to 42° C. Pour about 50 ml into a burette and dispense the required ml into a 100 ml beaker. Using a mercury thermometer, allow the liquid to cool to 38° C. then immediately pour onto the sample laid on a watch glass, setting on the styrofoam block. Start the data logger attached to the IR thermometer which is aimed on the center of the sample from 24" distance. Collect data on the IR temperature on 10 second intervals for 5 minutes.
Test a minimum of 3 samples and average the results. Use the temperature loss at selected intervals to characterize the cooling.
ARTIFICIAL URINE RECIPE
______________________________________Urine %______________________________________Urea 1.94Sodium Chloride .80Magnesium Sulphate .10Calcium Chloride .06Water 97.10______________________________________
An example of a preferred article using a fabric of this invention is a bed pad having a first layer of an open mesh, circular knit, raschel or tricot fabric of hydrophobic polyester, or polyolefin (e.g., polyethylene or polypropylene) fibers, and weighing 1.5 to 3.5 oz/yd 2 . The knit should be soft, pliant, and comfortable to a patient and have cover sufficient to minimize strikeback. Suitable commercially available pervious fabrics are "Coolmax" farbic by Deer Creek Fabrics, Stamford, CN and "Taltech" polypropylene fabric by D. V. Talbott Co., Minneapolis, MN. Two layers of a spunlaced absorbent fabric of the invention are used, as the absorbent inner layer, which contain 33% by weight round acrylic fibers containing an effective amount, i.e., less than 1%, of an antimicrobial agent for MRSA bacteria and 67% round, solvent spun, unmodified cellulosic fiber, such as "Tencel", and having a basis weight of 4.0 oz/yd 2 . A waterproof barrier layer is used which, to reduce slippage against a bed sheet, has a brushed or unbrushed tricot or single knit polyester fabric laminated to its outer surface a vinyl or polyurethane film; such as 6 oz/yd 2 vinyl sheet and a 2.2 oz. polyester jersey knit fabric laminate.
The two spunlaced layers and first knit layer can be sewn together in parallel straight lines running in one direction several inches apart as needed. This composite layer is also outer seam sewn with rounded corners.
The final pad composite, if desired, can be dot-adhesively laminated so that the former tri-layer composite and the latter vinyl/knit laminate become an integral composite structure having the desired integrity, such as to endure multiple laundry washing cycles.
The performance of a bed pad using an absorbent fabric of this invention is compared with two commercially used pads. The test pad of the invention is as described above. One control for the test was a commercialpad made by "Medline". Another control for comparison was a pad made by "Dundee". After two washings the pads are tested with the following results:
______________________________________Pad Type Test Medline Dundee______________________________________Absorbence Capacity, % 410 397 310Absorbence, 80% challenge, 4.2 22.2 23.6% lossWick rate, seconds/inch 2.8 14.8 13.6Heat Loss, °F.1 minute 6.7 5.0 5.63 minutes 12.2 10.5 10.95 minutes 15.5 13.4 14.2______________________________________
EXAMPLE
A spunlaced, water-absorbent fabric is prepared by making a blend of 35% by weight of 2.2 decitex, 25.4 mm long, crimped, antimicrobial "Biocryl" acrylic fiber and 65% by weight of 1.7 decitex, 25.4 mm, crimped "Tencel" solvent-spun, unmodified cellulosic fibers having a substantially round cross-section. The blend is formed into a web and subjected to a hydroentangling process of the type taught in U.S. Pat. No. 3,485,709 (Evans) using a water jet profile substantially as shown in Table I. The resulting fabric is stable to disentanglement and has a basis weight of 150 grams per square meter (GSM) and is over 1.0 mm thick.
Using the absorbent fabric, a bedpad is constructed in which two layers of the absorbent fabric are plied with a top layer of a warp knit fabric of hydrophobic polypropylene fibers containing apertures between the knit yarns of about 0.9 to 1.0 mm, effective diameter at a density of 25 apertures per cm 2 . The three layers are stitched together along the length of the composite with stitching at a spacing of about 9 to 10 cm and outer seam sewn with rounded corners in a bedpad size and shape.
A bottom sheet layer is attached to the 3-layer composite only at the edges which sheet layer has a basis weight of about 280 GSM. Of this, about 25 GSM is from a stabilized knit fabric of polyester filaments laminated to a sheet of plasticized polyvinylchloride, such as "Vintex" which can withstand laundrying but still be soft.
In tests with incontinent adult hospital patients, the pad is found to provide improved absorbency, with better wicking and less pooling, and stays cooler as compared to commercially used bedpads involving absorbent combinations of rayon and polyethylene terephalate fibers. | Spunlaced fabric having improved water absorbency containing a blend of certain hydrophilic cellulosic and acrylic fibers and layered absorbent materials made therefrom. | 3 |
FIELD OF THE INVENTION
The invention relates to a cable clamping apparatus, more particularly to a cable clamping apparatus for use in computer testing and assembly.
DESCRIPTION OF RELATED ART
An important feature of a computer's performance is the quality of signals transmitted through its cables. Therefore, it is very important to test the cables and ensure their quality.
A conventional method for testing the flexibility of cables is to use a cable bend-test device. However, it is expensive to use a cable bend-test device.
Generally there is a twisting-test apparatus to test the hinges on a notebook computer, which includes a test platform and a rocker. During the testing a main body of the notebook computer is fixed on the test platform, a top cover of the notebook computer is fixed on the rocker by a mounting device, the twisting-test apparatus manipulates the top cover to test the hinges which connect the top cover and the main body. However, the twisting-test apparatus is not configured for testing cables.
The principium of the twisting-test apparatus can, however, be used to test the flexibility of cables.
What is needed is a cable clamping apparatus that can cooperate with associated devices, such as a twisting-test device, used in the testing and assembly of computers to test cables.
SUMMARY OF THE INVENTION
An exemplary cable clamping apparatus for clamping cables, the cable clamping apparatus includes a base, a sliding member forming a plurality of dentations, and a blocking board forming a plurality of dentations corresponding to spaces between the dentations of the sliding member; wherein the blocking board is mounted on the base, the sliding member slides on the base to press against the blocking board, and the dentations of the sliding member cooperate with the dentations of the blocking board to clamp the cables. The cable clamping apparatus further comprises a mounting member and a screw, wherein the mounting member is mounted on the base, the sliding member is mounted between the blocking board and the mounting member, a screw hole is defined in the mounting member, a hole is defined in the sliding member corresponding to the screw hole, the screw is passed through the screw hole in the mounting member, and received in the hole.
Other advantages and novel features will become more apparent from the following detailed description when taken in conjunction with the accompanying drawing, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded, isometric view of a cable clamping apparatus in accordance with a first preferred embodiment of the present invention;
FIG. 2 is an enlarged view of a sliding member of FIG. 1 ;
FIG. 3 is an enlarged view of a blocking board of FIG. 1 ;
FIG. 4 is an assembled view of FIG. 1 ; and
FIG. 5 is an assembled view of a cable clamping apparatus in accordance with a second preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Refers to FIG. 1 , a cable clamping apparatus in accordance with a first preferred embodiment of the present invention includes a base 10 , a mounting member 20 , a screw 30 , a sliding member 40 , and a blocking board 50 .
A pair of elongated through holes 11 is defined at opposite ends in the base 10 consecutively. A first depressed portion 12 is formed on one side of the base 10 and a second depressed portion 14 is formed on the other side of the base 10 for the mounting member 20 and the blocking board 50 to be mounted thereon. The first depressed portion 12 defines two locating holes 13 and the second depressed portion 14 defines two locating holes 15 . The base 10 defines a receiving space 16 at a center thereof, for receiving the sliding member 40 and the blocking board 50 . A pair of elongated guiding grooves 17 is defined on an underside of the base 10 along opposite sides of the receiving space 16 consecutively and oriented in a same direction of the through holes 11 .
The mounting member 20 includes a base-plate 21 , and a protrusion 22 extending up from the base-plate 21 . A through hole 23 is defined in each end of the base-plate 21 , corresponding to the locating holes 13 of the first depressed portion 12 . A screw hole 24 is defined in a center portion of the protrusion 22 with an axis perpendicular to the axes of the through holes 23 .
Referring to FIG. 2 , the sliding member 40 has a generally rectangular-shaped configuration. The sliding member 40 includes a main body 41 , and a pair of guiding flanges 42 extending from opposite ends of a bottom of the main body 41 . A hole 43 (see FIG. 1 ) is defined in a center of a face of the main body 41 corresponding to the screw hole 24 of the protrusion 22 . The hole 43 does not pass all the way through the main body 41 . A plurality of dentations 44 is formed on an opposite face of the main body 41 .
Referring to FIG. 3 , the blocking board 50 includes a supporting member 51 and a bent portion 52 bent perpendicularly from an edge of the supporting member 51 . A plurality of dentations 53 is formed on the bent portion 52 corresponding to spaces between the dentations 44 of the main body 41 . Two screw holes 54 are defined in the supporting member 51 corresponding to the locating holes 15 in the second depressed portion 14 .
Referring to FIG. 4 , in assembly, the mounting member 20 is mounted on the base 10 , by known means such as two screws 25 received through the through holes 23 of the base-plate 21 of the mounting member 20 , into the locating holes 13 of the first depressed portion 12 . The blocking board 50 is mounted on the base 10 by known means such as two screws 35 extending through the screw holes 54 in the supporting member 51 of the blocking board 50 , into the locating holes 15 in the second depressed portion 14 . The bent portion 52 of the blocking board 50 extends into the receiving space 16 and out of a bottom of the base 10 . The sliding member 40 is inserted through the receiving space 16 from the bottom of the base 10 oriented such that the two guiding flanges 42 of the sliding member 40 are received in the guiding grooves 17 of the base 10 . The main body 41 extends out of a top of the base 10 . The screw 30 is passed through the screw hole 24 in the protrusion 22 of the mounting member 20 , and received in the hole 43 on the main body 41 of the sliding member 40 . Thus the sliding member 40 can be urged along a direction to abut the blocking board 50 , tapping cables therebetween, or urged along an opposite direction thereby increasing a distance between the sliding member 40 and the blocking board 50 , guided by the screw 30 and the guiding grooves 17 , the action being accomplished by rotation of the screw 30 .
The cable clamping apparatus can be advantageously used to replace a cable bend-twist device. The cable clamping apparatus cooperates with the twisting-test device in the following way: first, the cable clamping apparatus is mounted on a test platform of the twisting-test device by means of fasteners such as screws 100 passed through the through holes 11 be received by the test platform. Then a cable 200 is clamped by the cable clamping apparatus and an end of the cable 200 is tied to a rocker of the twisting-test device. Finally, parameters are set such that the twisting-test device bends the clamped cable in a desired manner testing the flexibility of the cable.
Referring to FIG. 5 , a cable clamping apparatus in accordance with a second preferred embodiment of the present invention. The cable clamping apparatus has a similar configuration to the first embodiment. A plurality of notches 62 is formed in the bent portion 52 of the blocking board 50 , corresponding to the dentations 44 on the main body 41 of the sliding member 40 . The dentations 44 of the main body 41 cooperatively engage with the notches 62 on the bent portion 52 to form at least an occluding member to clamp a cable 200 in order to prevent the cable 200 from gliding up and down.
It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments. | A cable clamping apparatus for clamping cables, the cable clamping apparatus includes a base, a sliding member forming a plurality of dentations, and a blocking board forming a plurality of dentations corresponding to spares between the dentations of the sliding member; wherein the blocking board is mounted on the base, the sliding member slides on the base to press against the blocking board, and the dentations of the sliding member cooperate with the dentations of the blocking board to clamp the cables. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to GB 0523106.3, filed 12 Nov. 2005.
BACKGROUND OF THE INVENTION
The present invention relates to a cooling arrangement and, more particularly, to a cooling arrangement utilised in a gas turbine engine with regard to inter-blade platforms.
It will be understood that the efficiency and output of a gas turbine engine is related directly to turbine gas temperature. In such circumstances it is desirable to operate a gas turbine engine at the highest temperature possible. At such temperatures it is necessary to provide cooling of components within the gas turbine engine in order to remain within acceptable temperature ranges for the materials from which various components are formed.
One of the most difficult locations to cool in a gas turbine engine is the inter-blade platform structure of the high-pressure turbine stage. In the past, embedded convective holes have been used, along with various film cooling configurations. However, these cooling schemes have proved problematic from a stress concentration point of view. The platform gas washed surfaces are highly-stressed both mechanically, due to the centrifugal loading, and thermally, due to the temperature gradients present. Drilling cooling holes has been successful in reducing the metal temperature level associated thermal gradients but these holes have significantly increased the local three-dimensional stress levels in the component and so have been counter-productive in terms of a desire for improved extension of component life.
More recently, as described in U.K. Patent application number 0304329.6, a cooling arrangement has been proposed which utilises a damper below a junction between platforms in order to release coolant. It will be understood that cooling air taken from the compressor used to cool the hot turbines is not used to extract work from the turbine. Extracting coolant, therefore, has an adverse effect on engine operating efficiency and it is, therefore, necessary to utilise cooling air as effectively as possible in order to reduce the amount of cooling air extracted. The controlled leakage of coolant through a series of staggered slots machined or cast into contact surfaces of a “Cottage Roof” damper is used to provide cooling about the platform. The coolant air is used initially to cool the disc post or zone between two disc fir tree mounting root serrations and this is bled from the cavity beneath the blade platform surfaces through the slots in the damper surface in order to cool the surfaces of the damper and the platform edges and then the coolant emerges into the gap or junction between two neighbouring platforms. The spent coolant then impingement cools the adjacent platform edge before escaping radially into the gas path and becoming entrained with the strong hot gas flows about the platform.
Although the “Slotted Cottage Roof Damper” arrangement described in the UK Patent application 0304329.6 provides distinct improvements and advantages over the previous approach, it will be appreciated that improvements can still be made. A primary disadvantage relates to the angle and, to a lesser extent, the velocity of the spent coolant emerging from the junction gap between neighbouring platform edges. In short, the spent coolant rapidly mixes with the hot gas-flows and, therefore, does not provide any significant cooling effect.
SUMMARY OF THE INVENTION
In accordance with the present invention there is provided an annular array of aerofoils for a gas turbine engine, the array defining a cooling arrangement, the arrangement comprising a junction gap between two overlapping platforms of adjacent aerofoils and a damper radially inwardly of the junction gap, a damper surface and a platform surface arranged to have a coolant flow passing between them in use, the arrangement characterised in that the junction gap is at an angle relative to a radial line to angularly present a coolant flow in use adjacent to an exit of the junction gap.
Preferably, the junction gap is angled ø at 60 degrees, but may be angled between 30 and 75 degrees. The angle of the junction gap varies along the length of the platforms.
Preferably, the damper surface has a ridge with surfaces either side and the angle of the junction gap is substantially aligned with one of the surfaces.
Normally, the junction gap forms a slot which is continuous along the length of the platforms.
Normally, the ridge is directly radially inward the slot.
Preferably, the surfaces are arranged such that respective coolant flows over both surfaces merge at the ridge to form the coolant flow presented adjacent to the exit of the junction gap.
Normally, the slot has an exit configured to present the coolant flow adjacent to the junction gap.
Preferably, the exit is arranged to present the coolant flow at a substantially consistent angle to gas flows over the platforms in use.
Typically, the exit comprises edges of each platform and one edge is displaced relative to the other edge.
Typically, one edge is displaced above the other edge such that the coolant flow is presented adjacent to the junction gap downstream of the raised component edge.
Preferably, a gas turbine engine includes an annular array of aerofoils as described in the above paragraphs.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which:—
FIG. 1 is a schematic cross-section of a prior cooling arrangement;
FIG. 2 is a schematic plan view of a cooling arrangement; and
FIG. 3 is a schematic cross-section of a cooling arrangement in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
As indicated above, a recent improved cooling arrangement for platform structures and particularly in an annular array of aerofoils in a gas turbine engine utilises a damper with a sloped ridge surface incorporating grooves through which coolant flows in order to cool the platform as well as the damper. This configuration is commonly referred to as a “Cottage Roof”. FIG. 1 is a schematic cross-section of a prior cooling arrangement 1 , generally described in U.K. Patent application number 0304329.6. Thus, the arrangement 1 has a first platform 2 and a second platform 3 , secured upon the mounting 4 , with a gap 5 between them. As indicated above, generally, in use these platforms and associated blades will be subject to high temperatures. Blade aerofoil coolant 6 will pass through conduits 7 in those aerofoils. The present cooling arrangement particularly relates to mounting disc and under-platform coolant flows 8 .
As described previously, these coolant flows 8 are utilised to cool the platforms 2 , 3 . A damper 10 is presented and generally is in contact with opposed platform cavity surfaces 12 , 13 . It will be noted that the damper 10 has a roof-like cross-section with a ridge 11 and diverging slopes either side which engage the surfaces 12 , 13 . Grooves are provided between the damper 10 and the surfaces 12 , 13 so that coolant flow can pass between these surfaces 12 , 13 and the damper 10 to exit through a slot 14 into a space 15 above the platforms 2 , 3 . This ejected and spent coolant flow 16 mixes with hot gas flows 17 as a result of operation of the blade aerofoils. In such circumstances, the platform section 2 will generally be considered a pressure surface whilst the platform section 3 will generally be considered a suction surface. As the coolant flow 16 rapidly and turbulently mixes with the hot gas flow 17 , it will be understood that some cooling effectiveness with regard to that flow 16 is lost, particularly with regard to potential in suction surface marked with XXXXX on the platform 3 . Ideally, so-called film cooling where a coolant gas lingers about a surface could be utilised in order to protect the platform 3 from hot gas impingement.
FIG. 2 provides a schematic plan view of the cooling arrangement depicted in FIG. 1 . As can be seen, the damper 10 incorporates slots 20 in order to present coolant flow 16 . This flow 16 as indicated mixes with hot gas flow 17 about aerofoils 21 and so normally provides little cooling effect.
It will be appreciated that the limitations with the prior cooling arrangement depicted in FIGS. 1 and 2 concerns the loss of coolant effect upon particularly the suction surface XXXXX of the platform 3 . This is generally due to the angle and, to a lesser extent, the velocity of the spent coolant which emerges from the exit of the slot 14 in the junction gap between the juxtaposed platforms 2 , 3 . As a direct result of the fact that the coolant emerges across the gas path 17 , that is to say perpendicular to the gas platform washed surfaces, there is no film cooling protection felt on the platform 3 suction surface XXXXX. It will be understood that this is due to the emerging stream of coolant from the slot being at a very different angle to the hot gas flow 17 direction and, consequently, the coolant 16 does not linger or “stick” by forced laminar flow to the platform 3 surface but rather becomes entrained and vigorously mixed with the hot gas flow 17 , so destroying any potential film cooling effect. It will also be understood that the aerodynamic mixing losses associated with the emerging coolant are substantial and this may have a detrimental effect on turbine efficiency and so the specific fuel consumption of the gas turbine engine overall. Further problems with this prior arrangement relate to the possibility that there may be an unpredictable positive or negative step between juxtaposed platform edges as a result of component dimensional tolerance stack-up. Such steps between the edges of the opposed platforms may again prove detrimental to aerodynamic component and turbine efficiency.
Finally, with regard to the prior cooling arrangement depicted in FIGS. 1 and 2 , it will be understood that the junction gap which creates the slot may change during engine cycling as a result of more expansion or less relative expansion between the components. Although there may not be an actual ‘pinch point’ where the platforms effectively engage and lock up with each other, there will be a point normally at the highest gas temperature condition experienced when the junction gap has a minimum dimension. During this period of minimum dimensions, the velocity of the emerging coolant 16 will reach a maximum so that if the cold or start-up gap has been set too narrowly then the coolant flow rate may be affected.
FIG. 3 provides a schematic cross-section of a cooling arrangement 31 for an annular array of aerofoils 52 in accordance with the present invention. Thus, two neighbouring blade platforms 32 , 33 are damped and cooled using a “cottage roof” damper 34 as described previously with regard to FIG. 1 . However, in the present cooling arrangement 31 , pressure surface 35 of the platform 32 has been slightly extended circumferential and a corresponding platform suction surface 36 has been shortened to form a partially overlapping seal arrangement. Coolant 37 leaks from the under platform cavity 38 through the damper surfaces in grooves upon surface 39 on either side of the roof ridge 40 and convectively cools the damper 34 and platform 32 , 33 edges. Coolant air 29 in the cavity 38 is taken from the usual compressor stages and coolant network. There is a junction gap 30 between platforms 32 , 33 . An emergent coolant flow 41 then cools by impingement the neighbouring platform edges 43 , 44 .
The coolant flow 29 meets in a continuous stream and flows between the juxtaposed neighbouring platform edges 32 , 33 in a continuous slot formed between the adjacent platform edges as a junction gap to emerge as coolant flow 41 . The coolant flow 41 emerges as a continuous film onto the platform suction surface XX before becoming entrained by hot gas secondary flows 42 that are a characteristic of a rotating aerofoil endwall geometry. The gentle mixing of the coolant 41 within the secondary flow hot gas 42 is achieved by consistently directing the film in substantially the same direction as the secondary flows 42 . In addition, a platform pressure surface YY and the suction surface XX are designed with a negative step at an exit 45 with respect to the hot gas secondary flow 42 direction. This step is effectively filled in with the emergent spent cooled flow 41 through the junction gap between the adjacent platforms 32 , 33 . As a consequence, the arrangement 31 is less sensitive to gas path discontinuities due to dimensional geometries. In short, the arrangement 31 is made such that there will always be a negative step between surface YY and surface XX. Similarly, the circumferential gap between neighbouring blade platforms 32 , 33 which effectively controls the exit Mach number of the flow 41 will be less important from an aerodynamic loss point of view as the coolant 41 is being directed in substantially the same direction as the hot mainstream secondary flow.
In view of the above it will be appreciated that the present cooling arrangement 31 utilises a “Cottage Roof” damper including slots for projection of coolant flow whereby there is a proportion of coolant passing over each sloped surface until combined to pass through the slot between the platforms. This slot, as indicated, is at the junction gap between the platforms and is at an angle ø relative to a radial line 50 . Although any angling of the junction gap is beneficial, a preferred range of angles ø is between 30 and 75 degrees and as shown in FIG. 3 the angle is approximately 60 degrees. The angle is preferably aligned with one of the slopes of the damper. In such circumstances the coolant flow emerges from the slot for appropriate film retention against the suction surface XX of the platform 33 for cooling effect and less turbulent loss with the hot gas flow 42 .
Furthermore, angling the junction gap may be more complex where either different flow pattern occurs within the space between aerofoils or where the platform edges are curved in the axial direction. In either of these circumstances, the angle of the junction gap may vary along the length or edge of the platforms.
In the above circumstances it will be appreciated that the damper 34 utilised in accordance with the present arrangement will be similar to that utilised with regard to FIGS. 1 and 2 . However, in an area immediately above the ridge 40 of the damper 34 , rather than as described previously with respect to FIG. 1 , the coolant flow components 39 passing over the respective slopes of the damper 34 to merge and project vertically upwards, it will be understood that one flow component 39 a will be generally aligned with the gap between the platform 32 , 33 whilst the other flow component 39 b will normally be presented across that flow component 39 a . In such circumstance there may be some coolant flow turbulence created directly above the ridge 40 . In such circumstances, generally, as illustrated in FIG. 3 , a mixing zone may be created to utilise or diminish the effects of such turbulence upon cooling within the arrangement 31 .
The junction gap 30 is a slot which is normally continuous along the length of the platforms 32 , 33 between the blades. In such circumstances a uniform film will be created upon the suction surface XX of the platform 33 to achieve efficient coolant effects.
It will be noted that in the cooling arrangement 31 there is now a lack of symmetry between the respective coolant flow components on either sloped side of the roof ridge 40 , namely flow components 39 a or 39 b of the damper 34 . It will be noted that the coolant flow component 39 a on the pressure side of the damper wets a greater surface than the coolant flow component 39 b on the suction side XX. In order to address this disparity the grooves on one side of the damper 34 may be increased or decreased in relative cross-section and the number and angular presentation of the grooves may be altered to achieve best cooling performance. | Cooling with regard to high-pressure turbine platforms is important in order to maintain gas turbine engine efficiency. Cottage Roof dampers located below junction gaps between adjacent platforms have been used but tend to present spent coolant flow at a high angle relative to hot gas flows about the aerofoil blades. The present arrangement has the junction gap angled such that the emergent coolant flow remains adjacent to the suction side to create a coolant film lingering above that suction side of the platform. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of U.S. application Ser. No. 10/360,988, “Chip Level Hermetic and Biocompatible Electronics Package Using SOI Wafers”, filed Feb. 7, 2003, the disclosure of which is incorporated herein by reference, which claims the benefit of U.S. Provisional Application No. 60/440,806, “Chip Level Hermetic and Biocompatible Electronics Package Using SOI Wafers”, filed Jan. 17, 2003, the disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to a hermetic integrated circuit and a method of making an integrated electronic circuit by utilizing silicon-on-insulator (SOI) techniques.
BACKGROUND OF THE INVENTION
[0003] This invention relates to electrically insulating thin film processes that are hermetic and that are used to encapsulate integrated circuits (ICs) for the purpose of forming a protective package for an electronic circuit, where the ICs are applicable to devices that are implanted in living tissue, such as neural prostheses or retinal electrode arrays. The package may have electrical feedthroughs to connect electrically to the outside environment. The electric circuit may interface with the outside environment optically (for example, infrared or laser) or via electromagnetic means, such as radio frequency (RF) and thus it may not need an exposed feedthrough. Additionally, the hermetic film may be made selectively electrically conductive in certain regions to facilitate signal transmission or power transmission.
[0004] The main drawback to thin film packaging of electronic circuits that are implanted in living tissue is that the process is typically three-dimensional since the entire IC needs to be packaged (encapsulated in a thin film). This results in long deposition times that add cost and that could exceed the thermal budget of the electronic circuits, thereby destroying the device. The invention describes a device and means for reducing the required deposition process time by allowing an equivalent package to be constructed in a two-dimensional deposition that covers several chips at the same time at the wafer level.
SUMMARY OF THE INVENTION
[0005] In accordance with a preferred embodiment of this invention, the apparatus of the instant invention is a hermetic and biocompatible electronics package that is made by applying silicon-on-insulator (SOI) technology and thin film deposition technology to enable large-scale production of individual integrated circuits for electronic packages that may be implantable in living tissue.
[0006] The SOI wafer is diced partially through its thickness. The spaces between the chips, die, or reticules are scored or semi-diced by one of several known means, in order to produce three-dimensional streets. The depth of these three-dimensional streets passes completely through the silicon layer and partially through the insulating layer. The three-dimensional streets are then coated along with the silicon layer to yield a hermetic electronics package that is suitable for implantation in living tissue.
[0007] In accordance with an alternative embodiment, the thin silicon layer may be transparent to light, thus allowing light to strike a photodetector on the surface away from the light source. This may have application in neural prostheses or retinal electrode arrays, for example, where light passes through the integrated circuit, strikes a photodetector, which in turn stimulates the retina to enable vision in a non-functioning eye. In this case, it passes through the insulator then through the silicon/integrated circuit layer.
[0008] A further embodiment places discrete electronic circuit components in the street area of the integrated circuit. The discrete component is then coated and thus part of the hermetically sealed, implantable electronics package.
[0009] The novel features of the invention are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings.
OBJECTS OF THE INVENTION
[0010] It is an object of the invention to produce a hermetically sealed integrated circuit using silicon-on-insulator technology and thin film deposition technology.
[0011] It is an object of the invention to produce a light transparent thin-layered integrated circuit chip using silicon-on-insulator techniques.
[0012] It is an object of the invention to produce a discrete integrated circuit that has discrete electronic components hermetically protected wherein select components are located in the street area of the integrated circuit.
[0013] Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 illustrates a cross sectional side view of the silicon-on-insulator chip assembly.
[0015] FIG. 2 depicts a cross sectional side view of the silicon-on-insulator chip assembly showing the insulating thin film.
[0016] FIG. 3 depicts a cross sectional side view of a single silicon-on-insulator chip.
[0017] FIG. 4 illustrates a cross-sectional side view of a light transparent insulator with a photoelectric cell.
[0018] FIG. 5 depicts a hermetically coated silicon-on-insulator IC with a discrete component.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] Starting with a base substrate wafer facilitates reducing process time. A silicon-on-insulator (SOI) wafer is used as the starting substrate as opposed to a standard silicon wafer. The invention is not limited to a silicon wafer, and it is envisioned that alternative semiconductors may be employed, such as gallium arsenide. In the case, where the integrated circuit (IC) is suitable for implantation in living tissue, a silicon-on-sapphire (SOS) or a silicon-on-diamond (SOD) wafer forms alternate embodiments, because the insulating layer is both biocompatible and bio-inert. A preferred embodiment is to the broader class of SOI wafers for electronic circuits for forming ICs for electronic circuits.
[0020] Using these wafers, the circuitry is designed using an electronics process that is known to one skilled in the art (e.g., 0.5 um CMOS) and this process is conducted to produce a wafer of functional die, such as ICs or chips). Typically, such wafers are post-processed, such as being thinned and polished, then diced into individual chips that are placed into their own packages. In a preferred embodiment, a wafer 2 is diced part of the way through, such that the spaces between the chips, die, or reticules are semi-diced by one of several known means in order to produce a three-dimensional street 8 having a depth that passes completely through a silicon layer 6 and partially through an insulator substrate 4 , as shown in FIG. 1 .
[0021] The insulator substrate 4 is preferably comprised of silica, although in alternative embodiments it may be comprised of glass or oxide materials that are electrical insulators. For implantation in living tissue, the insulator substrate 4 is preferably selected from a group of materials that are biocompatible and bio-inert, such as sapphire, diamond, silica, or oxide ceramics.
[0022] The main advantage of such a technique is that it eliminates the need to cover the back of the ICs with an electrically insulating and hermetic thin film, while permitting a single coating deposition process at the wafer level. The wafer level deposition of the insulating thin film 10 covers the sides of the three-dimensional street 8 , eliminating the need for any further deposition coatings. Choices for the deposition process for the insulating thin film 10 and material selection are known in the art. Candidate materials include diamond, such as ultra-nanocrystalline diamond (UNCD) or ceramics, such as alumina.
[0023] The thin film process is preferably a physical vapor deposition such as Ion Beam Assisted Deposition (IBAD), which like physical vapor deposition processes, is line-of-sight deposition, it none the less is capable of uniformly covering high aspect ratio features. In an alternative embodiment, a CVD process (which is not line of sight), such as microwave plasma chemical vapor deposition (MPCVD), is selected because it is also well suited to this requirement as it naturally fills in regions such as the three-dimensional street 8 . After a blanket deposition of the insulating thin film 10 over the entire wafer (which may be accomplished in several layers) the resulting structure appears as presented in FIG. 2 .
[0024] A further alternative embodiment utilizes an IC package that is at least partially transparent to light 14 , as illustrated in FIG. 4 , where the light 14 is preferably visible light. In alternative embodiments, the light 14 may include other types of electromagnetic radiation that is detectable with a sensor that is specific to the transmitted radiation. By using an SOI device, the insulator 12 may be chosen to have favorable transmission properties for electromagnetic radiation 14 . A preferred embodiment has a photoelectric cell 16 , which includes, but is not limited to, photo detectors, cadmium sulfide crystals, light sensors, phototransistors, or photodiodes that are located on a surface away from the light source.
[0025] In alternative embodiments, the photoelectric cell 16 may be any electronic circuit that responds to exposure to electromagnetic radiation 14 by generating an electric impulse. In FIG. 4 , the photoelectric cell 16 is located in the silicon layer 6 and is separated from the transparent insulator 12 by a portion of the silicon layer 6 . The invention is not limited to silicon layer 6 and it is envisioned that alternative semiconductor materials may be employed, such as gallium arsenide. In alternative embodiments, the photoelectric cell 16 is in direct contact with transparent insulator 12 . The photoelectric cell 16 may be located on the surface of the insulator 12 , in an alternative embodiment.
[0026] A preferred application is a device such as a neural prosthesis where the prosthesis may alternately be a retinal electrode array or demultiplexer, wherein the transmitted light 14 stimulates a photoelectric cell 16 , which in turn stimulates the retina, enabling a non-functioning eye to detect and see visible light. Alternative embodiments enable other types of electromagnetic radiation 14 , such as infrared or ultraviolet radiation, to be detected after the radiation passes through the transparent insulator 4 .
[0027] In yet another embodiment, FIG. 5 , a discrete electronic component 20 is placed in a hole 24 that passes part of the way through the thickness of insulator substrate 4 . The hole 24 is formed by any of the techniques that are know in the art, such as reactive ion etching, laser ablation, wet etching, dry etching, or combinations of these techniques. The hole 24 is filled with an electrically insulating fill 22 , preferably epoxy. After final dicing into a packaged chip, the discrete component 20 is hermetically protected in the three-dimensional street 8 of the hermetically packaged and implantable IC, having been covered with the electrically insulating thin film 10 . In a preferred embodiment, the discrete component 20 is a capacitor, although in alternative embodiments the discrete component 20 may be a resistor, filter, inductor, or a combination of these electronic circuitry elements.
[0028] The advantages of this packaging approach for an implantable IC chip is that all electronic circuitry is in a single package with internal electrical leads that are hermetically sealed in the package, thereby eliminating the need for external connections and feedthroughs, which are notoriously difficult to hermetically seal for long-term living tissue implant applications.
[0029] The chips can be singulated completely by a second dicing cut in the previously formed three-dimensional street 8 using known techniques, such as laser cutting, standard dicing, or a similar procedure. The resulting packaged chip is depicted in FIG. 3 .
[0030] Using the disclosed techniques, a wafer that contains numerous discrete chips, perhaps hundreds of discrete chips, is packaged in a fraction of the time that it previously took to package just one chip.
[0031] 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, the invention may be practiced otherwise than as specifically described. | The invention is directed to a hermetically packaged and implantable integrated circuit for electronics that is made my producing streets in silicon-on-insulator chips that are subsequently coated with a selected electrically insulating thin film prior to completing the dicing process to yield an individual chip. A thin-layered circuit may transmit light, allowing a photodetector to respond to transmitted light to stimulate a retina, for example. Discrete electronic components may be placed in the three-dimensional street area of the integrated circuit package, yielding a completely integrated hermetic package that is implantable in living tissue. | 7 |
THE PRIOR ART
It is known in the art of molding in plaster molds for the production of ceramic hollowware to support a plurality of such molds between a pair of frames mounted for rotation to successive positions during casting and in which the molds are retained between the frame members of one of said frames and an inflatable cell on the inner surface of the other of said frames by friction. U.S. Pat. No. 3,691,266, issued Sept. 12, 1972, discloses such an apparatus and method for molding ceramic hollowware.
While said prior art apparatus as disclosed in U.S. Pat. No. 3,691,266 and the method disclosed therein work very well for many applications, it has been found that for large molds used when casting large pieces of ceramic hollowware, the friction between the molds and the frame on one side and between the molds and the inflatable cell on the other side is insufficient to prevent the molds from slipping with respect to the frames during those steps of the process in which the weight of the molds and the slip therein is not directed downwardly against one of the frames but is exerted parallel thereto.
Additionally, for very small molds the cell must be inflated to such a degree that its point of contact with the mold becomes minimal and, further, as this limit is approached, the vulcanized seams of the cell are severely stressed.
Still further, it has been found that dumping of the excess slip in one sudden step results in a "sucking-in" or implosion of the casting wall in certain sizes of castings and for certain wall thicknesses.
BRIEF SUMMARY OF INVENTION
It has been found that by the use of a retaining member on one of the rotatable frames of a casting frame and the provision of cooperating grooves or notches on the cooperating molding halves, that much larger molds may be utilized without danger of the mold slipping with respect to the cooperating holding frames. It has also been found that by use of dual inflatable cells much smaller molds may be accommodated and castings may even be made with larger and smaller molds in the same frame thus permitting intermixing of mold sizes. The method of this invention also contemplates the pouring of the excess slip from the molds in at least two steps or stages thus preventing the sucking-in or implosion of the casting wall.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view, partially broken away, of a mold carriage assembly embodying the invention;
FIG. 2 is another perspective view of the mold carriage assembly but with the molds shown in place on one of the rotatable frame members;
FIG. 3 is a partial perspective view in which the upper frame member has been lowered to its operative position in opposition to the first frame member;
FIG. 4 is a partial perspective view of the carriage in the mold-filling position;
FIGS. 5, 6 and 6A are cross-sectional views in which the molds are positioned with their filler openings in various positions with respect to said carriage;
FIGS. 7 - 14 show various positions of the carriage during molding of hollowware articles.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The device of the present invention comprises a rotatable carriage generally indicated by the numeral 10 having end frame members 12 and 14 journaled in a fixed frame 16 by means of stub shaft 18 fixed to the end frame 12 and passing rotatably through a journal 20 mounted upon the fixed frame 16. A similar stub shaft 22 is fixed to the other end frame member 14 and passes through a cooperating journal 24 similar to the journal 20. The stub shaft 22 extends well beyond the journal 24 and has fixed thereon a sprocket wheel 26 having a chain 28 trained thereabout. The chain 28 extends downwardly and is also trained about a driving sprocket 30 fixed to the shaft 32 of a gear reducer 33 driven by an electric motor 34. An idler sprocket 36 shown only in the cutaway portion of FIG. 4 offsets the chain drive 28 towards the front of the apparatus as shown in order to permit the positioning of a collecting trough 38 beneath the carriage 10 for reasons that will hereinafter be apparent.
Mounted to the end frame members 12 and 14 is a first frame 40 and a second frame 42. The frame 40 comprises a first pair of metal, rectangular, tubular members 44 welded at one end to the end frame member 14 and at the opposite end to the end frame member 12. Between the members 44 are metal frame members 46 positioned transversely between members 44 and welded at their ends to said members 44. Toward the rear of frame 40 a second pair of frame members 45 are welded at their ends to end frame members 12 and 14. Extending transversely between frame members 45 are cross members 47. The upper surfaces of the longitudinal frame members 44 and 45 (the upper surface as viewed in FIG. 1) serve to support molds 50 as hereinafter more fully described. Running along the upper surface of one of the frame members 44 is a retaining member 48. The retaining member projects upwardly along the length of the member 44 and may be a bar, angle iron, channel member or any other cross section desired. As shown, the retaining member 48 is an upstanding flange welded to the upper surface of the frame member 45.
The other frame member 42 comprises opposite L-shaped end members 52 and 54 including a long upright arm 52a and 54a, respectively, and a shorter horizontal arm 52b and 54b, respectively, (upright and horizontal having reference to the showing in FIG. 1). The outer end of the arm 52b is pivoted at 56 to the end frame member 12 and the outer end of the arm 54b is pivoted at 58 to the end frame member 14. Longitudinal frame members 62 similar or identical in construction to the frame members 44 are welded at their opposite ends to the L-shaped end members 52 and 54. Between the members 62 and parallel therewith is a central frame member 64 which may be U-shaped in cross section, i.e. channel-shaped. The central channel member 64 is welded at its opposite ends to L-shaped end members 52 and 54. Positioned within the longitudinal channel member 64 is a dual cell inflatable member 60 having separate cells 60a and 60b each of which extends the full length, or substantially the full length, of the frame member 64. The inflatable member 60 may be of any suitable length of the frame member 64. The inflatable member 60 may be of any suitable material, but preferably each cell 60a and 60b comprises two overlying sheets of fabric-reinforced-synthetic rubber vulcanized together along their longitudinal and end edges. The adjacent walls of the cells 60a and 60b in the area indicated at 60c are vulcanized together as well. The entire assembly 60 of the two-celled-inflatable device is held in place by means of ties 68 which extend entirely around the inflatable device 60 and also around the longitudinal frame member 64. The ties 68 are preferably expandable strips of rubber located at chosen intervals along the length of the inflatable device 60. Metal cross braces 66 extend between the longitudinal members 62 and the channel member 64 in the frame 42 in order to lend rigidity and strength to the frame. The members 66 may be of any shape desired, but as shown, comprise rectangular tubular metal members welded to the longitudinal members 44, 45, 62 and 64 at their points of juncture.
As above mentioned, the frame 42 is pivoted at 56 and 58 and the access of movement runs through both pivots 56, 58. A stop member 72 secured as by welding to the end member 12 is engaged by the arm 52b of th L-shaped frame member 52 when the frame 42 is in its open position as shown in FIG. 1. A similar stop 73 is secured to the end member 14 and the horizontal leg 54b of the L-shaped end member 54 bears against the stop 73 when the frame 42 is in the open position in the same manner as just mentioned with respect to the leg 52b and the stop 72.
Torsion bars 70 and 74 are provided for aiding in counter-balancing the weight of the frame 42 in order to assist the operator in opening and closing the frame. The torsion bar 70 has one end secured in a plate 71 fixed to the bottom (as viewed in FIG. 1) of the L-shaped member 52. The other end of the bar 70 is secured in a plate 75 fixed to the end member 12 of the carriage 10. The torsion bar 74 is mounted in plates 77 and 79 fixed respectively to the members 52 and 14. It will be appreciated that torsion bars 70 and 74 are non-rotatably mounted in their respective plates 71, 75 and 77, 79. It will also be appreciated that as the frame 42 is pivoted about its pivots 56, 58, there will be a twisting or untwisting force applied to the torsion bars 70 and 74 depending upon the direction of movement about the pivot access 56, 58 and the pre-set twist that may be applied to the torsion bars 70, 74 when the device is assembled. Preferably, the torsion of the bars 70, 74 is adjusted in such manner that it is neutral in the 45° position - i.e. halfway between the fully open position shown in FIG. 1 and the fully closed position shown in FIG. 3. In this way, the torsion bars 70, 74 may assist both during the opening and the closing of the frame 42.
A suitable latch mechanism may be provided to latch the pivoted frame 42 in its closed position. As shown, it comprises a bell crank 69 mounted on a shaft 76 passing through one of the cross-frame members 66. The bell crank 69 at its opposite ends carries rods 78 extending through openings 80 in the end frames 52, 54 and (when the frame is closed) into openings 82 in the end walls 12 and 14. It will be appreciated that a handle, not shown, is fixed to the opposite end of shaft 76 and that by rotation of the bell crank 69 the rods 78 may be moved into and out of engagement with openings 82.
As shown in FIG. 3, there is a valve stem 84 mounted to extend through and to be exposed on the outer surface of the channel member 64 when the frame member 42 is in its closed position as shown in FIG. 3. The valve stem 84 communicates with the inflatable cells 60a and 60b with both cells being inflated simultaneously. The two cells 60a and 60b inflate simultaneously due to an opening 61 through the adjacent vulcanized walls of the two cells 60a and 60b. This opening 61 is in the area 60c previously mentioned where the two separate cells are vulcanized together.
The trough 38 is preferably a fabric reinforced rubber material which extends beneath the device. As shown in FIG. 4, it is preferred to use two separately operated machines back to back. As generally indicated in FIG. 4, the first machine is indicated at 100 and the second machine arranged back to back with the first is indicated at 101. The trough 38 extends beneath both machines whereby it may serve two molding devices and is supported by the front legs 17 on the two devices. As shown in FIGS. 1 and 4, the trough 38 is supported by the legs 17 of the frame 16 on the device generally indicated at 100. The opposite edge of the trough 38 is similarly supported from the front legs (not shown) of the device 101.
The trough 38 may be supported in any one of a number of ways from the legs 17; however, as shown in FIG. 4, the support comprises a lower metal bar 19 welded to the legs 17. Another metal bar 21 overlies the edge of the trough 38 and is screwed by means of screws or bolts 23 to the fixed bar 19 thus clamping the trough 38 tightly between the fixed bar 19 and the removable bar 21. It will be noted that the idler sprocket 36 shown in FIG. 4 in dotted lines offsets the chain 21 so that the chain passes by the edge of the trough 38.
While the normal position of the molds is such that the filler opening 50c faces outwardly between the frames 40 and 42 as shown in FIGS. 3, 4 and 7 - 14, the design of the frames 40 and 42 permits of alternate arrangements as shown in FIGS. 5, 6 and 6a.
As shown in FIG. 5, the mold 50 has its filler opening 50c positioned between the frame members of the frame 40. Specifically, the opening 50c is positioned between the inner frame member 44 of the pair of frame members 44 and the inner frame member 45 of the pair of frame members 45. It will be appreciated that the opening 50c could as well have been shown positioned between the pair of members 44 or between the pair of members 45. While many mold shapes lend themselves to positioning of the filler opening 50c facing outwardly between the frames 40 and 42 as shown in FIGS. 1 - 4, certain shapes and sizes of molds are more conveniently handled if it is possible to fill the same by turning the side of the mold uppermost and filling through the frame and the side of the mold as shown in FIG. 5. It will be appreciated that the design of the frame 40, contrary to prior devices, easily lends itself to the use of such side filling molds since it provides spaces between the pair of members 44, the pair of members 45, and between the inner members of the pairs 44 and 45. It will be appreciated that when filling a mold through the frame 40 and through the side of the mold as shown in FIG. 5, it is necessary to rotate the carriage 10 180° from the position shown in FIG. 3 as compared with a rotation of 90° when the opening 50c is positioned between the frames 40 and 42 as shown in FIGS. 1 - 4. That is to say, that only a 90° rotation is required to bring the molds from the position shown in FIG. 3 to the filling position shown in FIG. 4 whereas if side filling is used then, in that event, a 180° rotation to the position shown in FIG. 5 is required.
FIGS. 6 and 6a show other positions for the filler opening 50c which may be utilized with the frames 40, 42 of the carriage 10 of this invention. As shown in FIG. 6, the opening 50c is also on the side of the mold, but it is the opposite side to that shown in FIG. 5. As shown in FIG. 6, the filler opening 50c is positioned between the frame members 64 and one of the frame members 62 of the upper pivoted frame 42. This position has the advantage that immediately upon closure of the upper frame 42 the molds 50 may be filled without rotating the carriage 10.
FIG. 6a shows the opposite situation from that shown in FIGS. 1 - 4 in that the mold opening 50c is positioned to the rear of the device (to the left as viewed in FIG. 1). In certain sizes and shapes of molds, this arrangement is advantageous despite the fact that there may be some slight difficulty in filling the molds in view of the location of the torsion bars 70 and 74. For these molds, however, the torsion bars 70 and 74 present very little problem since they are not of large cross-sectional size. It will be appreciated that in order to arrange the opening 50c of the molds uppermost as shown in FIG. 6a, the carriage 10 must be rotated 90°, but in the opposite direction from that used when moving from FIG. 3 to FIG. 4. Accordingly, the carriage 10 permits the filling of the molds 50 from any one of the four sides and it requires only that the carriage 10 be rotated to position the openings 50c upwardly. It will be obvious to anyone skilled in the art that the following operational sequence, which is directed to the use of molds with their openings directed as shown in FIGS. 3 and 4, will be slightly changed by the use of molds having their openings 50c in one of the other positions illustrated by FIGS. 5, 6 and 6a.
A manual switch 86 is provided for operating the motor 34 in either direction and for stopping the motor with the carriage 10 in any desired position. A timer 88 for operating the motor automatically is also provided.
OPERATION
The sequence of operation of the device and steps of the method are shown schematically in FIGS. 7 - 14. As shown in FIG. 7, the pivoted frame 42 is open and the molds 50 have been placed in position resting upon the upper surfaces of the frame members 44 and 45. The molds 50 comprise upper mold half 50a and lower mold half 50b and have filler openings 50c. A notch 90 in the lower mold half 50b is positioned in cooperating relationship with the retaining member 48. The notch 90 is shaped in such a manner as to be readily engaged with the retaining member 48 and yet to firmly position and retain the molds 50 against any movement to the left or right as viewed in FIG. 7. The molds 50 may be all of the same size or of varying sizes, but all will have their filler opening 50c positioned in the same direction. As shown, the filler opening is toward the right in FIG. 7. Other positions for the filler opening are possible as explained below. The operator then pivots the frame 42, as shown in FIG. 8, until it resides in the position shown in FIG. 9 at which point he latches the frame 42 in position by rotating the bell crank 69. He then inflates the inflatable cells 60a and 60b by applying an air hose of a conventional type 92 to the inflation valve. This expands both of the cells 60a, 60b against the upper surface of all of the molds 50 and presses against the molds 50 with sufficient firmness to hold them in place. The operator then rotates the mold assembly 90° to the upright position shown in FIG. 10 by operating the motor actuation switch 86. He then fills all the molds 50 with a conventional ceramic slip supplied through a hose 94 filling the molds 50 through openings 50c. The timer 88 is then actuated. The timer runs for any predetermined period of time which may be adjustable and which is determined by the desired thickness of the ceramic component of the slip that is to be built up in the inner surface of the mold. At the conclusion of the preset time, the timer actuates the motor 34 and the motor in turn rotates the carriage 10 to a first pouring position such as that shown in FIG. 11. While FIG. 11 shows the carriage 10 as having been moved approximately 90° to the left (counter-clockwise in the figures) from the position of FIG. 10, the actual position of the carriage in FIG. 11 depends upon the setting of the timer 88 which is set to rotate the carriage 10 for a predetermined number of seconds. It is only necessary that at this first pouring stage the outlet 50c be tipped far enough to permit at least the beginning of the pouring of the excess slip from the molds. As shown in FIG. 11, the position of the outlet 50c will permit approximately half or a bit more of the excess slip to be poured.
The carriage 10 remains in the position of FIG. 11 (or other chosen pouring position) for a dwell time determined by yet another adjustment on the timer mechanism 88.
Upon the completion of the dwell time in the position shown in FIG. 11 the timer will then operate the motor 34 again to rotate the carriage 10 to the second pouring stage or step as shown in FIG. 12 in which the mold opening 50c is positioned downwardly. When all of the excess slip has been poured from the molds in the position of FIG. 12 of the carriage 10, the operator then operates the motor control 86 to rotate the motor 34 in the opposite direction to return the carriage to the position shown in FIG. 13 which, it will be appreciated, is the same as the position of FIGS. 7 - 9 and represents a rotation of 270° from the position shown in FIG. 12. The operator then unlatches the pivoted frame 42 by rotation of the bell crank 69 and again tips the pivoted frame 42 upwardly into its open position. He then removes the "spare" from the pouring neck or opening 50c of the mold in conventional manner and lifts the upper half 50a of each mold upwardly, tilting them backwards to lean against the pivoted frame 42 as shown in FIG. 14. The formed ceramic ware 96 may then be removed from the lower supporting mold halves 50b.
It will be appreciated that instead of the two pouring stations as shown in FIGS. 11 and 12 the timing device 88 may be so construction as to provide for more than two pouring stages with a variable dwell time adjustable for each stage. Similarly, the timing device could be so constructed as to provide for very slow but continuous rotation of the carriage 10 from the position shown in FIG. 10 to that shown in FIG. 12. For such an operation, the speed reducing gear 33 is replaced with a variable speed device and the speed thereof made subject to the control of the timer 88. Further, the timer 88 may advantageously be interlocked with the manual motor operating device 86 to prevent manual operation of the motor 34 during that portion of the cycle in which the timer 88 controls rotation of the carriage 10 -- i.e. from completion of the filling of the molds in FIG. 10 to completion of emptying of the molds in FIG. 12. | A rotatable carriage for supporting split-type plaster molds for molding ceramic hollowware is disclosed, in which the molds are retained between two frames rotatable to a succession of positions in which the molds are retained in place between the framework of one of said frames and a dual cell inflatable member on the inner face of the other of said frames. The first of said frames includes a retaining member engaging the outer surface of said mold to prevent said mold from slipping relative to said frames. A new casting method is disclosed in which the slip is poured from the filled molds in at least two steps with the rotatable frames being rotated to a different position for each of said pouring steps. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. provisional application 60/837,225 filed Aug. 10, 2006; and U.S. provisional application 60/840,292 filed Aug. 25, 2006, both incorporated by reference in their entireties.
FIELD OF THE INVENTION
[0002] This invention relates to health care information systems.
BACKGROUND
[0003] The last decade has seen an explosion of scientific insight into the molecular pathways affecting normal and diseased cells, rapidly translating into molecularly targeted therapeutic options for patients. The era of customized medicine and target-specific therapy has arrived. Increasingly therapeutic choices will be made based on the patient's specific gene profile, the tumor specific over-expression of receptors and the stage of the life-cycle of the disease. With this rapid evolution of both fundamental biology and the rapid translation of this knowledge into clinical medicine there is an increasing need for all stakeholders in the management of health care to access real time and objective information upon which to base therapeutic decisions in an evidence-based fashion. With the advent of these next generation technologies both as approved drugs (Herceptin, Avastin, Tykarb, Tarceva, Irressa, Erbitux, Gleevec etc) and drugs in clinical development, the need for the practicing physician and the patient to access and implement up to date clinical information are now paradoxically greater than when the therapeutic choices were fewer.
[0004] These issues are present in many areas of health care. While the examples in this application describe life-threatening diseases such as cancer, the same applications are intended for all life-threatening diseases afflicting patients such as cardiac disease, neurodegenerative disease, diabetes, infections, transplantation, inflammatory disease, etc. The complexity is highlighted in, for example, the war against cancer. For the past 50 years the armamentarium available to oncologists and cancer patients has been cytotoxic medicines that act in some fashion to poison the cell to stop division and hormonal therapies which deprive cancer cells of steroidal growth factors. In the last decade an exponential gain has occurred in the knowledge of specific receptors which are over-expressed in tumor cells. Discovery efforts have led to the elucidation of a multitude of receptor types (Her2, MEK, mTOR, FT, SPARC etc) and a network of messenger molecules at the intra-cellular level. These and others provide potential targets for next generation therapeutics and currently over 300 molecules are under development. The receptors and pathways involved in cancer and its progression are complex. There are multiple intersecting receptors and pathways, many of which undergo cross-talk and interactivity. Of clinical relevance, one or more of the receptors and the response in any one patient may differ from those of another patient with the same cancer type. Thus, there are responders and non-responders in patients with the same cancer type with differing molecular profiles. Such complexity suggests a need for specific treatments and carefully evaluated treatment choices. What is efficacious in one patient may have a greater, lesser, or absence of an effect in another. The knowledge and efficacy specificity is evolving dramatically and represents a huge challenge to the practicing clinician to keep abreast of the optimal cocktails of drugs under varying molecular conditions, and clearly almost impossible for the lay patient to maintain state of the art knowledge in the highly technical field of molecular medicine. An integrated active information system, including but not limited to a seamless, real time system, based on objective state of the art evidence, customized to the specific and event-driven episodes of the disease as it progresses, is sorely needed. Such a system would have substantial positive implications in both the practice and cost of medicine.
[0005] The complexities involved in the day to day operational activities affecting drug innovation, drug manufacture, clinical trial management, drug reimbursement and drug distribution, combined with the specific and personalized dynamic affecting doctor-patient relationships in situations whereby the patients face life-threatening crises, are enormous. The complexity of these interrelations and interactions, as well as the absence of working knowledge of all aspects of the above supply chain of a medicament (from discovery to administration to a patient) have prevented the creation of a seamless, fully integrated, real-time interconnectivity which would allow for the implementation of clinical decisions to provide best practices in patient care, with the most cost-effective method of providing such care, with the same quality standards provided whether treatment is provided in an academic tertiary center or whether from a rural remote setting, with the opportunity to avoid medication errors.
[0006] There are multiple unmet needs facing each element of the health care supply chain, including clinical information needs, drug development clinical trial needs, supply needs and cost-containment needs, which would benefit from being addressed in a comprehensive system. Nonlimiting examples of such needs include:
[0007] With the rapid expansion of targeted and customized drug development, there is a need for the innovator to access patient populations with appropriate phenotypes for clinical trial accruals.
[0008] With the rapid expansion of both preclinical and clinical knowledge of multiple new clinical protocols, there is the need for the practicing clinician and payor to maintain state of the art awareness of best practices and evidence-based pathways.
[0009] With the rapidity and breadth of clinical trial development, there is the need for patients to be aware of newly approved drugs or clinical protocols addressing their specific disease and perhaps their specific tumor receptor type.
[0010] With the ability to intervene early and prevent life-threatening conditions such as infection, thereby preventing hospitalization, there is a need for both patient and physician to access timely alert systems allowing preventative intervention and hence cost-savings.
[0011] With complexities of next generation drug manufacture involving the production of, for example, complex protein molecules, nanoparticles and monoclonal antibodies, there is a need for real time understanding of demand to accommodate the long lead times necessary to ensure adequate supply both at the clinical trial stage and approved stage of the drugs life-cycle.
[0012] With standards of care differing from location to location and physician to physician there is a need to standardize care based on evidence-based protocols.
[0013] With the large number of medication errors resulting in serious adverse events and death, there is a need to reduce such errors via electronic checks and use of bar coding.
[0014] With the poor compliance in patients regarding following prescribed medications, there is a need to monitor and alert patients and physicians when this occurs.
SUMMARY
[0015] To date, no system exists which adequately integrates the needs of a diverse community of entities with interests linked by the treatment of a patient, for example, the care-giver, the physician, the innovator, the clinical trial manager, the payor, the manufacturer and the supplier. The present method and system is directed to this. In some embodiments in accordance with the present invention, an integrated system links any one or more of the care-giver, the physician, the innovator, the clinical trial manager, the payor, the manufacturer and the supplier. In some embodiments an integrated system links all of the care-giver, the physician, the innovator, the clinical trial manager, the payor, the manufacturer and the supplier. Such an integrated information system, including but not limited to one which provides connectivity via the web in real-time, would revolutionize the practice of health care and create tremendous advances in the supply chain. Such advances include but are not limited to:
accelerating clinical development of next generation therapeutics, promoting evidence-based best practices, providing transparency and access of information to patients in real-time including medical information relevant to their daily care, providing efficiency and real-time support tools, for example, alerts to one or more of care-givers or patients, allowing rapid and timely preventative or therapeutic intervention in the entire life-cycle of that patient's disease, allowing transparency to the payor in the patients day to day care and both provider and patient's needs with ultimate cost savings in best practices and preventative care, allowing for cost savings through the efficiency, preventative and supply aspects of health care management throughout the life-cycle of the disease, allowing standardized quality standards of care, minimizing medication errors, and ensuring compliance with prescribed medications and completing dosage.
[0025] In some embodiments an integrated system in accordance with the invention provides any one or more of the benefits described herein. In some embodiments an integrated system provides any one or more of the benefits described hereinabove. In some embodiments an integrated system described herein provides all of these benefits. In some embodiments an integrated system described herein provides all of the benefits described herein. In some embodiments an integrated system described herein provides all of the benefits described hereinabove.
[0026] Contemplated is a computer enabled method for exchange of patient related medical data, comprising the acts of: providing a patient record having data pertaining to a patient, the record being held by a first health care organization; communicating over a computer network at least a portion of the record to a second health care organization, thereby establishing a shared patient record; and allowing access to the shared patient record over the computer network by a third health care organization. Further, the computer network is, e.g., the Internet and the access is via a conventional web browser.
[0027] Further, each of the organizations is one, e.g., of a physician's office, hospital, pharmacy, and insurer, payor for medical care, drug manufacturer, drug distributor, drug developer, clinical trial manager, laboratory, or test facility. Further, the data includes at least one of the patient's genotype, gene-over-expression, or specific drug response. Further, the method includes: establishing a database relating to a clinical trial of a drug, medical device, or procedure; and storing at least a part of the shared patient record in the database. Further, the method includes accessing the database to show a particular patient's medical status and clinical trial status.
[0028] The method further includes: providing a distribution function; and accessing the shared patient record by the distribution function; wherein the distribution function determines distribution of drugs, medical devices, or medical supplies to the patient. Further, the distribution function performs activities selected from the group consisting of calculating drug doses, managing local drug inventories, and managing central location drug inventories. The method further comprises providing a database of general clinical data; associating data from a patient record with the database; and providing the associated data from the database to a health care provider.
[0029] The method further includes: receiving a patient record including medical test results; determining a predetermined condition in the test results; and updating the shared patient record according to the predetermined condition. The method further includes: accessing the shared patient record; and providing data from the shared patient record to one of a robotic health care device, a patient monitoring device, or a medication compliance monitor.
[0030] Further contemplated is a system to perform this method and including computer code conventionally executed at a web server computer to carry out the method and accessed via a client software application running in a conventional web browser at a client computer. The server and client software (programs) may be coded in any convenient computer language.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 shows one example of architecture of the system described herein.
[0032] FIG. 2 shows flow of a transaction using the FIG. 1 system, involving a patient seeing a physician, obtaining a prescription, and filling it.
[0033] FIG. 3 shows interconnections between elements of FIGS. 1 and 2 .
DETAILED DESCRIPTION
[0034] One example of an integrated information system described herein may utilize the Internet and its associated well known client-server technologies. The Internet provides a means to create a unique architecture to accomplish a web-based real-time seamless integration between a plurality of stakeholders (actors) involved in the supply, provider and consumer chains of both approved drugs and next generation drugs in clinical development. In some embodiments the integrated systems described herein provide a technology platform that connects any two or more of the patient, the patient's specific genotype, the prescribing physician, the payor, the drug manufacturer, the distributor, the innovator, drug developer and clinical trial manager. In some embodiments the integrated systems described herein provide a technology platform that connects each of the patient, the patient's specific genotype, the prescribing physician, the payor, the drug manufacturer, the distributor, the innovator, drug developer and clinical trial manager. In some embodiments the integrated systems described herein provide real-time information on a case by case basis of the most optimized therapeutic pathways, based on objective analyses of the therapeutic options available to the patient. In some embodiments the integrated systems described herein operate seamlessly and in real-time.
[0035] Also, see U.S. Pat. No. 6,012,035 to Freeman, Jr. et al, U.S. Pat. No. 6,845,393 to Murphy et al, and U.S. Pat. No. 7,069,308 to Abrams, all incorporated herein by reference in their entireties. These show various elements and linkages between people and organizations employing communications networks, useful in embodiments of the present system.
[0036] In light of the rapid evolution of medicine and the recent findings that there are responders and non-responders to specific therapy depending on a patient's disease, such as a tumor type, as well as depending on the stage of the life-cycle of the disease, such as a tumor, this system provides a “virtual consultant” system (software) to the prescribing physician by linking the patient's specific characteristics, for example the genotype and level of gene expression, to up to date knowledge. In some variations the knowledge pertains to one or more of approved targeted therapeutics as well as next generation technologies in development. By making this information and evidence-based pathway options available in real-time to both patient and physician, the doctor patient relationship may be enhanced, and allow informed clinical decisions and best practices to be more easily implemented.
[0037] Furthermore the system may be configured to provide medical alerts to one or more of patient, treating physician, and care-givers on a timely or real time-basis allowing for rapid and timely intervention. In some variations the integrated systems described herein provide medical alerts to each of the patient, treating physician, and care-giver. Such alerts may prevent or minimize the need for hospitalization by averting deterioration in patients struggling with disease. Such alerts include but are not limited to any one or more of changes in biological markers, changes in biochemical and hematological status, changes in radiological status. In some variations the integrated systems described herein are configured to respond to each of changes in biological markers, changes in biochemical and hematological status, changes in radiological status. This system allows not only for rapid and efficient notification of the patient and physician, but also may be configured to indicate treatments based on evidence-based analyses of the best therapeutic options needed to address the patient's health status.
[0038] A key element in the system architecture is the integration and interfacing of currently decentralized systems (referring to patients 10 and providers 14 , 40 , 42 , 46 , 38 , 50 , 54 ) with centralized databases providing one or more of updated evidence based pathway options, payor inputs, clinical trial inputs, inventory management controls and distribution (see FIG. 1 ).
[0039] These interconnected systems include any one or more of:
Patient Medical Records 12 a , 12 b , 12 c , 12 d , 12 e : These electronic records are maintained by the physician's office 14 or other care provider organizations respectively 40 , 42 , 46 , 38 , 50 , 54 as a record of the patient's medical history including, for example, the patients molecular profile status, biochemical marker status, clinical and radiological status and genotype 11 . In some variations the integrated systems described herein provide one or more of interfaces and alerts relating to therapeutic options or interventions relating to the patients clinical status and all of these together collectively are the shared Patient Medical Record 13 .
[0041] In one embodiment, the combined clinical analysis together with the biological markers triggers an automatic drop down menu of best practice pathways. In some variations these pathways are generated in a separate, periodically or continuously updated data base (the evidenced-based clinical pathway). In some variations such pathways are generated by any one or more of thought leaders, practicing physicians, third part organizations or guidelines, such as NCCN guidelines, and periodically or continuously updated to interface with the Patient Medical Record via a virtual (computer based) consultant program 60 .
[0042] In some variations, with abnormal laboratory results alerts are transmitted to the shared Patient Medical Record 13 informing the patient of the need to take a certain action such as resume a medication, return to the doctor's office for a repeat blood test, etc. In some variations a system of alerts to one or more of patient and physician will occur after or in anticipation of adverse drug interactions or drug to drug interactions. With regard to the care-giver, the Patient Medical Record will allow the physician to establish the record of the treatment protocol and allow the pharmacist and nurse to execute the order. In some variations a bar-coding system ensures that inadvertent incorrect drug administration is minimized. One (non-limiting) version of a process for doing this is shown in FIG. 2 with various elements having the same reference numbers as in FIG. 1 .
Patient Medical Record 13 : A web-based seamless interface between the various medical Records 12 a , . . . , 12 e allows patient transparency and portability Payor or insurer Interface: A seamless interface between other information systems, such as the payor data accumulator and the Patient Medical Record 13 allows, for example, for clarity of patient eligibility criteria, reimbursement status and obligations between provider 14 , payor 40 and patient Clinical Trial Interface 20 : In some variations, similar to the evidenced based pathway data base, a separate periodically or continuously updated clinical trial data base is interfaced with the Medical Records 12 a , . . . , 12 e . In some variations an automatic drop down menu of, for example, ongoing trials which covers the patient's current clinical and molecular status. This clinical trial interface is upgradeable for electronic data capture of patients who elect to enter into such clinical trials and linked to a centralized Clinical Trial Manager Center 38 for centralized data capture Logistic Center Interface 24 : The Medical Record 13 is linked to both a local (e.g., physician's office 14 , pharmacist 54 or hospital 50 ) drug storage system and a centralized logistic distribution center 26 . This interface 24 provides mechanism for calculating dose, inventory management at the infusion site, bar coding for inventory management and safety, inventory management at centralized distribution center and supply management from such center.
[0047] Connectivity to Remote Robotic Monitoring Systems 32 : The Medical Records 12 a , 12 e and Clinical Trial Interface 38 systems have the capability to interface with a multitude of robotic monitoring and therapeutic (including minimally invasive and surgical procedures) systems currently existing or in development, allowing both remote monitoring of the patient's status as well as remote alerts and prompts for treatment intervention and even for remote management of procedures. Examples of remote technology with which interconnectivity is possible include but are not limited to:
Wireless broadband platforms such as Motiva developed by Philips Electronics. Remote Robotic Health-care Giver 38 such as the Remote Presence Robot developed by Intouch Health. Remote Patient Monitoring Devices 40 such as Personal Watcher developed by HomeFree Systems whereby vital signs are monitored via a wearable watch monitor. Medication Compliance Monitors 44 such as those in development by Tyco International, Eaton Corp (Home Key System) and Accenture (On-line medicine cabinet).
[0052] In some embodiments the integrated systems described herein link any one or more of the individual databases, information sources, and parties described herein. In some embodiments the integrated systems described herein link some or all of the individual databases, information sources, and parties described herein.
[0053] The following properties of each interconnective element of FIGS. 1 and 2 shown further in FIG. 3 are parts of the above describe distributed data base 70 and provide for a holistic, integrated delivery of health care across the entire spectrum of the health care network including the chain involving physician 14 , patient 10 , patient care facility 50 , patient caregiver 74 , diagnostic service provider 78 , drug dispenser 54 , drug distributor 46 , drug manufacturer 42 , drug innovator 80 , clinical trial manager 38 , and payor 40 . This integrated system will simultaneously and in an integrated fashion address critical issues facing health care today including:
Providing standardized quality of care to the patient, whether the patient is a remote rural setting or in an urban tertiary care environment, based on evidence-based outcomes. Limiting medication errors which account for thousands of adverse events and death annually. Maintaining patient privacy. Providing timely and preventative interventions avoiding complications requiring costly and life-threatening hospitalization. Providing state of the art customized care based on patient's diagnostic genotype and pathological biomarkers and state of the art clinical medicine and clinical trials. Saving health care costs by providing efficient delivery of health care throughout the continuum including treatment, drug costs and efficient payor approval process.
[0060] Patient Medical Record # 1 of FIG. 3 is the final and validated Medical Record 13 . Any entries between other “shadow” records (records 2 to 8 of FIG. 3 ) require conventional validation processes and tools prior to acceptance in the Medical Record 13 . This Record 13 will be portable and establish HIPPA compliant methods to maintain patient privacy. This Record will provide efficient time-saving and knowledge gathering tools to allow the physician to provide evidence-based care with national quality standards by allowing the physician real-time access to the following information and data:
Patient's full prior history including all diagnostic tests and pathological findings. Patient's current clinical, diagnostic lab and imaging studies. Based on the patient's current clinical, genotype and pathological status, immediate real-time access to current standards of care with regard to diagnostic testing and therapeutic interventions. Such access is provided by the National evidence-based standards data base 68 which may interconnect with the patient's profile via the depicted interconnective data base. Real-time access to the patient's diagnostic services data including access to real-time remote monitoring devices. Interconnectivity with the patient shadow charts in which the patient may enter data, symptoms etc. and physician will have sole authority to add to the Patient's Medical Record information from the patient's shadow chart. Physician alerts regarding abnormal diagnostic data (tied to interactive alerts and intervention recommendations from the National standards data base 68 ). Interactivity with the Payor Medical Record # 6 and Practice Management Record # 8 generated as a result of patient care 90 to ensure payor coverage for therapeutic and diagnostic intervention and reducing the need for manual confirmation of benefits.
[0068] Patient Medical Record (# 2 of FIG. 3 ). The feature of this Record 13 is the ability to establish a “shadow” record based on the initial inputs from the Patient Medical Record # 1 and all the validated inputs from Records 1 to 8 of FIG. 3 . This Record is comprehensive and allows the patient to transport his or her life-time information from care-giver to care-giver. The treating care-giver is able to receive inputs from the patient but will only add it to the final Medical Record 13 upon validation or approval by the physician or other care-giver.
[0069] The Record 13 provides the patient the following benefits:
Access to state of the art treatment pathways based on evidence-based outcomes. Access to diagnostic information in real-time allowing preventative interventions. Access to medication bar code information, avoiding medication errors. Compliance tools to remind the patient of the need of therapeutic, diagnostic intervention including compliance with treatment plan. Access to knowledge of insurance status.
[0074] The remaining Records # 3 to # 8 in FIG. 3 have similar or related content and functionality according to the indicated use and associated medical provider entity (as shown in FIG. 3 ) involved with that particular record.
[0075] Further, in the development of next generation therapeutics (drugs, devices, treatments) as well as the delivery of current medical care, huge inefficiencies exist, adding to the cost of health care and reducing the quality of such care by medication errors, delays in innovative drug development and delays and inefficiency of information transfer between patient, physician, healthcare giver, diagnostic services, clinical trial operations and drug distributor and manufacturer. To date, seamless and integrated web-based systems linking each of these entities and providing significantly increased efficiencies have not been developed and are sorely needed. The interactive web-based system described in this application provides methods to directly address issues described below, but is not so limited. For example:
Doctor-Patient Communication: Through the direct interconnectivity between the various Medical Records 12 a , . . . , 12 e , mundane and inefficient administrative patient care tasks such as appointment scheduling or rescheduling can occur through web-based communication. This communication includes question-answer interaction relating to the patient's status and progress. Since the entire body of patient data is available to the physician or other caregiver instantaneously, the physician has more time to spend with the patient instead of managing administrative tasks. Each medical record is structured such that the entire record (rather than just individual pages) can be accessed or printed by a computer with a single key stroke, for maximal portability. This has some similarities to the known Vista system, implemented currently in the VA (Veteran's Administration) health care system. Clinical-Investigator-clinical trial monitor communication (e.g., for drug and device and treatment trials): The current method of validating a clinical trial case report with the actual patient chart is highly inefficient and usually requires the physical travel of the clinical trial monitor to the clinical sites. Instead, with the current system this monitoring can be done from any location using the national clinical trial database 86 . Drug Dispensing-administration interaction: By bar coding the medication (or its container) and associating the bar code with the Medical Records as well as with the insurer reimbursement system and the drug inventory management system 88 , there are multiple points of validation so as to prevent the patient from receiving an incorrect medication. If such an event happens, upon detection by the present system an alert is provided to warn the healthcare giver. Such an alert is triggered by a bar code patient identifier on, e.g. the patient's ID bracelet, for both in or out patients. The interconnectivity of these bar codes from drug manufacturer, distributor, payor, physician, patient and pharmacist and further being tied to robotic dispensing systems is highly advantageous.
[0079] This disclosure is illustrative but not limiting; further modifications will be apparent to those skilled in the art in light of this disclosure, and are intended to fall within the scope of the appended claims. | Web-based system and computer enabled method for storage and distribution of medical information pertaining to patient care. This allows various actors in the medical care field to exchange information pertaining to particular patients in the form of electronic medical records. | 6 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a method and apparatus for the improved recovery of C2 and/or C3 and heavier components from hydrocarbon gases.
[0002] In conventional processes for extracting propane and C2 and/or C3 bearing gases are treated by a combination of expansion of heavier components from hydrocarbon gases (or compression followed by expansion) heat exchange and refrigeration to obtain a partially condensed stream which is collected in a feed separator having a pressure typically in the order of 50 to 1100 psia and a temperature in the order of −50° to −200° F. These conditions of course can vary substantially, depending on the pressure and temperature conditions necessary to achieve partial condensation for a particular gas, and the pressure and temperature at which the feed is available to the process. The liquid resulting from partial condensation is supplied to a fractionation column called a “heavy ends fractionation column” as a mid-column feed while the vapor from the feed separator is used to generate reflux by partially condensing the overhead vapors from the heavy ends fractionation column through appropriate heat exchange means. In a typical system the heavy ends fractionation column will operate at a pressure less than that of the feed separator (possibly allowing for a small pressure drop as the partially condensed liquid passes from the separator to the heavy ends fractionation column) and the heavy ends fractionation column overhead vapors leave at a temperature in the order of −120° to −160° F. for C2 and heavier recovery and −20° to −70° F. for C3 and heavier recovery. The heat exchange of these overhead vapors against the residue vapors from the light ends fractionation column provides partial condensate which is used as a reflux to the light ends fractionation column.
[0003] Pre-cooling of the gas before it is expanded to the light ends fractionation column pressure will commonly result in formation of a high-pressure condensate. To avoid damage to the expander, the high pressure condensate, if it forms, is usually separated in the feed separator, separately expanded through a Joule-Thomson valve and used as a further feed to the mid-portion of the heavy ends fractionation column.
[0004] Refrigeration in such a process is sometimes entirely generated by work expansion of the vapors remaining after partial condensation of the high pressure gas to the light ends fractionation column operating pressure. Other processes may include external refrigeration of the high pressure gases to provide some of the required cooling.
[0005] When processing natural gas, feed is typically available at line pressure, of 900 to 1100 psia. In such case expansion to a pressure in the order of 150 to 500 psia is common. In an alternate process, facilities may be designed to extract propane or propylene from refinery gases. Refinery gases commonly are available a pressure of 50 psia to 250 psia. In this case, at the convenience of the process designer, the light ends fractionation column may be designed to operate at a pressure below the pressure of the refinery gas which is available, i.e., perhaps 50 to 100 psia, so that work expansion can be used to supply refrigeration to the process. This will result in lower light ends fractionation column temperatures and will increase potential heat leakage and other engineering problems associated with cryogenic temperatures. It is also possible in this case to compress the refinery gas to a higher pressure so that it may be thereafter expanded in a work-expansion machine to afford refrigeration to the overall process.
[0006] A typical flow plan of a process for separating C3 and heavier hydrocarbons from a gas stream is illustrated in U.S. Pat. No. 4,251,249 to Jerry G. Gulsby.
SUMMARY OF THE INVENTION
[0007] In one embodiment of the invention, there is described a process for separating a hydrocarbon gas containing at least methane, ethane and C3 components into a fraction containing a predominant portion of the ethane and lighter components and a fraction containing a predominant portion of the C3 and heavier components or a predominant portion of the methane and lighter components and a fraction containing a predominant portion of the C1 and/or C2 and heavier components, in which process
[0000] (a) the feed gas is treated in one or more heat exchangers, and expansion steps to provide at least one partly condensed hydrocarbon gas, providing thereby at least one first residue vapor and at least one C2 or C3-containing liquid which liquid also contains lighter hydrocarbons; and
(b) at least a portion of the C2 or C3-containing liquids is directed into a distillation column wherein said liquid is separated into a second residue containing lighter hydrocarbons and a C2 or C3-containing product; comprising:
(1) cooling said second residue to partially condense it;
(2) intimately contacting at least part of one of said first residue vapors with at least part of the liquid portion of the partially condensed second residue in at least one contacting stage and thereafter separating the vapors and liquids from said contacting stage;
(3) supplying the liquids thereby recovered to the distillation column as a liquid feed thereto; and
(4) directing the vapors thereby recovered into heat exchange relation with said second residue from the distillation column, thereby to supply the cooling of step (1), and thereafter discharging said residue gases; the improvement comprising:
(5) withdrawing a portion of the first residue vapor;
(6) cooling said portion of the first residue vapor to partially condense it;
(7) intimately contacting at least part of one of said first residue vapors with at least part of the liquid portion of the partially condensed portion of the first residue in at least one contacting stage and thereafter separating the vapors and liquids from said contacting stage;
(8) supplying the liquids thereby recovered to the distillation column as a liquid feed thereto; and
(9) directing the vapors thereby recovered into heat exchange relation with said portion of the first residue from the separator, thereby to supply the cooling of step (6), and thereafter discharging said residue gases;
the improvement further comprising:
(10) withdrawing a portion of the C2 or C3 containing liquid from the separator;
(11) directing said portion of the C2 or C3 containing liquid from the separator into a heat exchange relationship with the liquid product from the contacting device;
(12) cooling said portion of the C2 or C3 containing liquid from the separator;
(13) intimately contacting at least part of one of said first residue vapors with at least part of the C2 or C3 containing liquid from the separator in at least one contacting stage and thereafter separating the vapors and liquids from said contacting stage;
(14) supplying the liquids thereby recovered to the distillation column as a liquid feed thereto;
(15) directing the vapors thereby recovered into heat exchange relation with said portion of the first residue from the separator, thereby to supply the cooling of step (6), and thereafter discharging said residue gases; and
(16) directing the liquids thereby recovered into heat exchange relation with said portion of the C2 or C3 containing liquid from the separator, thereby to supply the cooling of step (11), and thereafter discharging said liquids to a heavy ends fractionation column.
[0008] The contacting step (2) is carried out in a feed separator/absorber which includes fractionation means for vapor/liquid counter-current contact and
[0000] (i) wherein said partly condensed second residue is introduced into said separator/absorber above or at an intermediate point in said fractionation means, whereby the liquid portion of it passes downwardly through said fractionation means; and
[0009] (ii) wherein said partly condensed portion of the first residue is introduced into said separator/absorber above or at an intermediate point in said fractionation means, whereby the liquid portion of it passes downwardly through said fractionation means; and wherein said portion of the cooled C2 or C3 containing liquid from the separator is introduced into said separator/absorber above or at an intermediate point in said fractionation means, whereby the liquid portion of it passes downwardly through said fractionation means; and
[0000] (iii) said at least part of one of said first residue vapors is supplied to said separator/absorber below said fractionation means, whereby the first residue vapor rises through said fractionation means in counter-current contact with the liquid portion of the partly condensed second residue.
[0010] The fractionation means in said separator/absorber provide the equivalent of at least one theoretical distillation stage arranged to contact at least part of one of said first residue vapors with the liquid portion of the partly condensed second residue.
[0011] The fractionation means in said separator/absorber provide the equivalent of at least three theoretical distillation stages arranged to contact at least part of one of said first residue vapors with the liquid portion of the partly condensed second residue.
[0012] At least part of one of said first residue vapors are co-mingled with the liquid portion of the partially condensed second residue, liquid portion of the partially condensed portion of the first residue and portion of the cooled C2 or C3 containing liquid from the separator.
[0013] At least part of one of said first residue vapors are comingled with both the liquid portions and vapor portions of said partially condensed second residue, partially condensed portion of the first residue vapor and portion of the cooled C2 or C3 containing liquid from the separator.
[0014] Further, there is described an apparatus for separating a hydrocarbon gas containing at least methane, ethane and C3 components into a fraction containing a predominant portion of methane and ethane and lighter components and a fraction containing a predominant portion of the C2 or C3 and heavier components in which apparatus
[0000] (a) one or more heat exchange means and one or more expansion means are provided which are cooperatively connected to provide at least one partly condensed hydrocarbon gas, providing thereby at least one first residue vapor and at least one C3-containing liquid which liquid also contains lighter hydrocarbons; and
(b) a distillation column connected to receive at least one of said C2 or C3-containing liquids which is adapted to separate the C2 or C3-containing liquids into a second residue containing lighter hydrocarbons and a C2 or C3-containing product;
the improvement comprising:
(1) heat exchange means connected to said distillation column to receive said second residue and to partially condense it;
(2) heat exchange means connected to said distillation column to receive said a portion of the first residue and to partially condense it;
(3) contacting and separating means connected to receive at least part of one of the first residue vapors and at least part of the liquid portion of the partially condensed second residue and partially condensed first residue vapor and to comingle said vapor and liquid in at least one contacting stage, which means include separation means for separating the vapor and liquid after contact in said stage;
(4) said means (2) and (3) being further connected to supply the liquids separated therein to the distillation column as a liquid feed thereto;
(5) said means (2) and (3) also being connected to direct the vapors separated therein into heat exchange relation with said second residue and portion of the first residue from the distillation column in said heat exchange means (1); and
(6) heat exchange means connected to said distillation column to receive said liquids and to cool the portion of the C2 or C3 containing liquid from the separator.
[0015] The contacting and separating means includes fractionation means for countercurrent vapor/liquid contact and wherein said means is connected to receive the portion of one of first residue vapors to be treated therein below said fractionation means and to receive the portion of said liquids from the partially condensed second residue, portion of the partially condensed first residue and portion of the cooled C2 or C3 containing liquid from the separator to be treated therein above or at an intermediate point in said fractionation means said fractionation means thereby being adapted so that the first residue vapors rise there-through in countercurrent contact with partially condensed second residue and portion of the partially condensed first residue and being further adapted so that the portion of the C2 or C3 containing liquid from the separator is cooled by the liquids exiting the fractionation means.
[0016] The fractionation means includes vapor/liquid contacting means which are the equivalent of at least one theoretical distillation stage.
[0017] Thecontacting and separating means (2) comprise means for comingling at least part of one of said first residue vapors with the liquid portion of the partially condensed second residue, liquid portion of the partially condensed portion of the first residue and portion of the cooled C2 or C3 containing liquid from the separator.
[0018] The contacting and separating means (2) comprise means for comingling at least part of one of said first residue vapors with both the liquid and vapor portion of said partially condensed second residue, said partially condensed portion of the first residue and portion of the cooled C2 or C3 containing liquid from the separator.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a schematic of a hydrocarbons separation process according to the invention.
[0020] FIG. 2 is a schematic of an alternative embodiment of a hydrocarbons separation process according to the invention.
[0021] FIG. 3 is a schematic of a preferred embodiment of a hydrocarbons separation process according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0022] The present invention provides an improved process for recovering C2 and/or C3 and heavier components from hydrocarbon-bearing gases. In the improved process of the present invention the overhead vapor from the heavy ends fractionation column and a portion of the first residue vapor from the separator are partly condensed and at least a portion of the C2 or C3 containing liquid from the separator into a heat exchange relationship with the liquid product from the contacting device and then at least the respective liquid condensates and cooled liquid are combined with at least the vapor from the partially condensed feed gases described above in the heavy ends fractionation column feed separator which, in the present invention, also acts as an absorber. The feed separator/absorber is designed to afford one or more contacting stages. Usually such stages are assumed for design purposes to be equilibrium stages, but in practice this need not be so. Vapor from the feed separator/absorber passes in heat exchange relation to the overhead from the heavy ends fractionation column, thereby providing partial condensation of the heavy ends fractionation column overhead vapor and portion of the first residue vapor, and liquid from the feed separator/absorber is supplied to the heavy ends fractionation column as an upper or top liquid feed to the column.
[0023] If the separator/absorber contains an absorption section, such as packing, or one or more fractionation trays, these stages will be assumed to correspond to a suitable number of theoretical separation stages. Our calculations have shown benefits with as few as one theoretical stage, and greater benefits as the number of theoretical stages is increased. We believe that benefits can be realized even with the equivalent of a fractional theoretical stage. The partially condensed heavy ends fractionation column overhead, partially condensed portion of the first residue vapor, and at least a portion of the cooled C2 or C3 containing liquid from the separator are supplied above or at an intermediate point of this section, and the liquid portions of these streams passes downward through the absorption section. The partially condensed feed stream is usually supplied below the absorption section, so that the vapor portion of it passes upwardly through it in countercurrent contact with the liquids from the partially condensed heavy ends fractionation column overhead. The rising vapor joins the vapors which separate from partially condensed heavy ends fractionation column overhead above the absorption section, to form a combined residue stream.
[0024] While described above with respect to a preferred embodiment in which overhead, a portion of the first residue vapors are condensed and, at least a portion of the cooled C2 or C3 containing liquid from the separator are used to absorb valuable ethane, propane, etc. from the expander outlet vapors, we point out that the present invention is not limited to this exact embodiment. Advantages can be realized, for instance, by treating only a part of the expander outlet vapor in this manner, or using only part of the overhead condensate or none of the separator liquid as an absorbent in cases where other design considerations indicate that portions of the expander outlet or overhead condensate should bypass the feed separator-/absorber. We also point out that the feed separator/absorber can be constructed as either a separate vessel, or as a section of the heavy ends fractionation column.
[0025] In the practice of this invention there will necessarily be a pressure difference between the separator/absorber and the heavy ends fractionation column which must be taken into account. If the overhead vapors pass through the condenser and into the separator without any boost in pressure, the feed separator/absorber will assume an operating pressure slightly below the operating pressure of the heavy ends fractionation column. In this case the liquid feed withdrawn from the separator/absorber can be pumped to its feed position in the heavy ends fractionation column. An alternative is to provide a booster blower in the vapor line to raise the operating pressure in the overhead condenser and separator/absorber sufficiently so that the liquid feed can be supplied to the heavy ends fractionation column without pumping. Still another alternate is to mount the feed separator/absorber at a sufficient elevation relative to the feed position of the liquid withdrawn therefrom that the hydrostatic head of the liquid will overcome the pressure difference.
[0026] In still another alternative, all or a part of the partially condensed heavy ends fractionation column overhead and all or part of the partially condensed feed can be combined, such as in the pipe line joining the expander output to the feed separator/absorber and if thoroughly intermingled, the liquids and vapors will mix together and separate in accordance with a relative volatility of the various components of the total combined streams. In this embodiment the vapor-liquid mixture from the overhead condenser can be used without separation, or the liquid powder thereof may be separated. Such co-mingling is considered for purposed of this invention as a contacting stage.
[0027] In still another variation of the foregoing, the partially condensed overhead vapors can be separated, and the all or a part of the separated liquid supplied to the separator/absorber or mixed with the vapors fed thereto.
[0028] The present invention provides improved recovery of propane or propylene per amount of horsepower input required to operate the process. An improvement in operating horsepower required for operating a heavy ends fractionation column process may appear either in the form of reduced power requirements for external refrigeration, reduced power requirements for compression or recompression, or both. Alternatively, if desired, increased C3 recovery can be obtained for a fixed power input.
[0029] Turning to the figures, FIG. 1 is a schematic of a hydrocarbon separation process according to the invention. A hydrocarbon bearing gas natural gas is fed through line 20 to a warm gas/gas exchanger 22-E3000 and then to a chiller 22-E3400. Refrigeration is supplied through line 52 and 53 with some refrigerant removed through a valve assembly before entering the chiller.
[0030] The chiller has a line 54 which will withdraw refrigeration for recompression and liquefaction. The cooled gas stream is fed through line 21 through a cold gas/gas exchanger 22-3100 to a cold separation column 22-D1000.
[0031] The hydrocarbon gas stream will be separated into two streams with the tops leaving through line 22 and the bottoms through line 25 to line 16 . The bottoms will pass through a valve in line 26 for flow control and will rejoin line 26 to line 35 where they will enter subcooler 22-E3200. These cooled hydrocarbon gases leave the subcooler through line 36 and enter light ends fractionation column 22-T2000. The hydrocarbon gas stream that is not diverted will continue through line 37 to the light ends fractionation column 22-T2000 at the top of the column.
[0032] The tops from the cold separation column 22-D1000 will leave through line 22 and reach a junction with line 24 . Line 24 will also contain a valve assembly PV which is used to control the flow of the stream in Line 24 . The remainder of the tops from the cold separation column flow through line 23 through an expander/compressor 22-X6000. This expanded hydrocarbon gas stream will be fed through line 29 into the light ends fractionation column 22-T2000.
[0033] The tops from the light ends fractionation column 22-T2000 will leave through line 39 and pass through line 40 where they will pass through cold gas/gas exchanger 22-E3100 and warm gas/gas exchanger before passing through line 55 to an expander/compressor 22-C6000 where the compressed gas stream will enter and expander/compressor discharge cooler 22-E4100 through line 59 . The discharged gas stream will exit through line 58 and for sales or further processing as required.
[0034] Line 56 contacts line 55 and some of the hydrocarbon gas will be drawn off before entering the expander/compressor 22-C6000 and recovered for use as fuel gas. A valve assembly is present in line 56 for controlling the quantity of the material to be used as fuel gas.
[0035] The bottoms from the light ends fractionation column 22-T2000 will exit through line 31 . These bottoms comprise an intermediate liquid stream that required further fractionation. Line 31 is in fluid communication with a transfer pump 22-P5000A/B which directs the bottoms from the light ends fractionating column to line 33 and into the top of a heavy ends fractionation column 22-T2100.
[0036] Part of the bottoms from the cold separator column 22-D1000 are diverted through line 27 where they will pass through a level control valve that flows through line 28 into the heavy ends fractionating column.
[0037] A stream comprising a cooler, intermediate product liquid is withdrawn from the heavy ends fractionation column 22-T2100 through line 41 which is fed to a side heater 22-E3800 which will heat the stream and return it through line 42 to a point lower in the heavy ends fractionation column from which it was withdrawn. Another side steam is withdrawn from the heavy ends fractionation column 22-T2100 through line 43 which is fed to a heavy ends fractionation column reboiler 22-E3700 which will heat the side stream. This stream is fed to a trim reboiler 22-E4000 where it will be further heated before being returned through line 44 to a point lower in the heavy ends fractionation column from which it was withdrawn. Line 45 will supply hot oil from a hot oil supply (not shown) to the trim reboiler 22-E4000 while line 46 will return hot oil from the trim reboiler.
[0038] A line at the bottom of the heavy ends fractionating column will remove some of the hydrocarbon comprising mainly of Cts and less volatile hydrocarbons or C3s and less volatile hydrocarbon and direct it to a valve in line 51 , Line 51 receives bottoms from the heavy ends fractionating column 22-T2100. Line 47 feeds the bottoms from the heavy ends fractionating column and feeds them to a heavy ends fractionating column bottoms pump 22-P5100A/B which feeds the bottoms through line 49 to a product exchanger 22-E3600 which feeds the bottoms through line 50 to the product pump 22-P5200A/B. This pump directs the bottoms through line 51 where they can be directly fed to a pipeline.
[0039] A valve in line 49 will allow bypass of the product exchanger 22-E3600 and divert the flow to an air or water cooled heat exchanger when the plant is operated in the C3 and heavier recovery mode. After cooling, these bottoms can be fed back into line 49 for feeding to the product exchanger 22-E3600.
[0040] The tops from the heavy ends fractionation column 22-T2100 will exit through line 34 and pass through a subcooler 22-E3200. Line 38 exits the subcooler 22-E3200 and connects to a valve PV. The tops from the heavy ends fractionation column will be fed through line 30 into the light ends fractionation column 22-T2000 where they will be further fractionated for reentry back into the heavy ends fractionation column as a reflux stream.
[0041] FIG. 2 represents an alternative embodiment of the present invention. In this alternative description all the designations as employed in describing FIG. 1 are re-employed and mean the same for the description of the unit operations taking place. In FIG. 2 , a liquid/liquid exchanger is present between the heavy ends fractionation column and the light ends fractionation column.
[0042] The bottoms from the cold separator column 22-D1000 will be fed through line 25 to a junction connecting to a valve LV and line 28 for entry into the heavy ends fractionation column. The feed through line 26 will connect with a liquid/liquid exchanger 22-E3900 and pass through into the light ends fractionation column 22-T2000.
[0043] FIG. 3 represents another alternative embodiment of the present invention. In this alternative description all the designations as employed in describing FIG. 1 are re-employed and mean the same for the description of the unit operations taking place. In FIG. 3 , the bottoms from the light ends fractionation column 22-T2000 are fed through line 31 to the light ends fractionation column bottoms pump 22-P5000A/B which feeds the bottoms through line 32 and valve LVI to subcooler 22-E3200. Valve LVI may be opened and closed to divert some of the bottoms back to the bottom of the light ends fraction column.
[0044] The bottoms fed to the subcooler 22-E3200 are now lower in temperature and are fed through line 33 into heavy ends fractionation column 22-T2100 where they will be further fractionated.
[0045] While this invention has been described with respect to particular embodiments thereof, it is apparent that numerous other forms and modifications of the invention will be obvious to those skilled in the art. The appended claims in this invention generally should be construed to cover all such obvious forms and modifications which are within the true spirit and scope of the invention. | A process for separating a hydrocarbon gas into a fraction containing a predominant portion of the methane or ethane and lighter components and a fraction containing a predominant portion of the C2 or C3 and heavier components in which the feed gas is treated in one or more heat exchange and expansion steps; partly condensed feed gas is directed into a separator wherein a first residue vapor is separated from a C2 or C3-containing liquid; and C2 or C3-containing liquids at substantially the pressure of separation are directed into a distillation column wherein the liquid is separated into a second residue to recover a C2 or C3-containing product. A portion of the vapor and/or a portion of the liquid from the first hydrocarbon vapor/liquid separation is further cooled and introduced into a fractionation column to increase the C2 or C3 and heavier hydrocarbons recovery from the natural gas stream. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention concerns a device and process for an antenna array with switchable wide angle or directional characteristic, comprised of individual antennas for increasing the directional resolution and angular coverage, in the sense of monopulse-antenna, of which the total antenna mean radiation pattern or directional characteristic is characterized by a sum diagram and a differential diagram, wherein the individual antennas are connected via a network of phase-shifters or hybrid junctions, wherein the antenna array includes a sum input for selecting the individual antennas, so that the antenna mean radiation pattern or directional characteristic exhibits a sum diagram, and wherein the antenna array includes a differential input for selecting the individual antennas so that the antenna mean radiation pattern or directional characteristic exhibits a differential diagram.
In automobile short-range sensor technology, as well as in mobile communications, there is an increasing demand for sector-wide coverage of large angle areas. This problem is presently addressed by the employment of separate individual antennas respectively serving sectors. If the antenna characteristic (this term being used herein to mean aerial radiation pattern or directional characteristic) is to be switchable and/or adaptively adjustable, or, as the case may be, if for space saving or aesthetic reasons a large number of individual antennas is not appropriate, then antenna arrays must be employed. In the case of large main lobe breadths and large slewing angles, the slewing angle which can be realized is strongly limited on the basis of strongly increasing “grating-lobes”.
2. Description of the Related Art
The conventional technique for solving this problem involves employment of conformal, or angle preserving, array antennas. Such antennas presently remain in part in the research stage or are still too expensive for employment in series production.
From U.S. Pat. No. 4,044,359 a device is known, which is designed for suppressing interfering signals. Herein, by the targeted interaction of two antenna systems, directional information is obtained, which is subsequently used for improved suppression of interfering transmissions.
In the reference by Kuga et al. (Kuga, Nobuhiro et al., Beam-Switched planar array antenna for mobile communications, Electronics and Communications in Japan, Part 1, Vol. 81, No. 3, 1998, pp 57-63) an antenna array with large angle coverage is described, wherein the individual angular distributions are covered by means of the switchable arrangement of antenna groups, which exhibit two switchable antenna characteristics respectively offset by 180°. For example, herein two antenna groups arranged at right-angles to each other are shown, wherein these four segments cover an angle area of 360°.
Patent publication DE 27 09 758 B2 shows an emitter group arranged in a circular shape for finding the azimuthal direction. Herein already multiple antennas lying along a segment of a circle are assembled into an emitter group and driven via a circuit matrix network. These individual emitter groups are driven in the sense of a monopulse antenna, which utilizes a sum diagram and one single differential diagram. The high angular resolution of the antenna array is herein achieved by suitable arrangement (here circular shaped, for angle coverage of 360°) of the individual emitter groups and by the comparison of the respective received signals with each other.
In the literature, Skolnik (Skolnik, M., Radar Handbook, 2 nd ed., McGraw-Hill Inc., New York) describes diverse antenna arrays which are suitable for operation as monopulse antennas (see in particularly p. 6.24, table 6.1). It is herein however presumed according to FIG. 6.19 (p. 6.23), that the antenna arrays utilize one sum and one individual differential characteristic. As for the particularly noteworthy feature, reference is made to the problem arising with respect to the directional effect of the antenna characteristic, which is based upon the fact that during the dimensioning of the antenna a compromise must be found between the efficiency of the summation characteristic of the antenna and the differential characteristic of the antenna.
The conference handout of Hannan (Hannan, P., Loth, P., A Monopulse Antenna Having Independent Optimization of the Sum and Difference Modes, IRE Int. Conv. Rec., pt.1, March 1961) concerns the problem of finding an optimal compromise with respect to the efficiency of sum and differential characteristics of the antenna diagram. For this, an antenna array is described, which is comprised of individual antennas, which are connected with each other at a fixed phase relationship via coupling with a network comprised of a hybrid junctions. In this manner it is achieved that the angle area of the emission lobe of the differential characteristic is efficiently narrowed.
The selection schematics which can be found in the literature are always based on the presumption that there will always be two groups of antenna elements provided next to each other and arranged counter-phasic to each other.
SUMMARY OF THE INVENTION
It is thus the task of the invention to provide a process and a suitable device, with which it becomes possible to sector-wise cover a large angle area with conventional high frequency elements and antenna elements.
This task is solved in that at least one of the phase shifters or hybrid junctions of the network is switchable, so that the antenna mean radiation pattern or directional characteristic exhibits further differential diagrams by the resulting change of the phase behavior due the selection of the individual antennas, or in that at least one of the phase shifter or hybrid junctions of the network is switched, such that the antenna mean radiation pattern or directional characteristic exhibits further differential diagrams due to the resulting change of the phase behavior upon the selection of the individual antennas. In accordance therewith antenna elements are driven such that the individual elements are individually operable and can be selected to be either in-phase or in phase-opposition relative to each other.
BRIEF DESCRIPTION OF THE DRAWINGS
Beginning with an equally spaced arrangement of four antenna elements, the invention will be described in greater detail in the following on the basis of the illustrative embodiments shown in the figures. There is shown
FIG. 1 the simulated antenna diagrams, depending upon differing selections of the antenna elements,
FIG. 2 a schematic circuit diagram of the inventive device and
FIG. 3 an exemplary embodiment of the inventive device.
DETAILED DESCRIPTION OF THE INVENTION
Of course the invention is not limited to the provision and control of precisely four antenna elements, but rather can be expanded to any other number of elements as required.
The below discussed illustrative embodiment is based upon an equally distanced arrangement of four antenna elements. In order to represent an in-phase or, as the case may be, phase-opposition selection of the elements, in the following the symbols ‘+’ and ‘−’ are employed, wherein the elements indicated with the same symbol are driven in-phase to each other and at the same time are driven 180° phase delayed in phase-opposition to the other antenna elements.
FIG. 1 shows antenna diagrams with respect to three differing selects of the antenna elements. This concerns an arrangement or array of micro strip conductors which are arranged in four lines or rows and are spaced apart with the 0.54 multiple of the wave length of the operating frequency. By constructive measures the side lobes of the antenna arrangements were surpressed by 8 dB (Tapering: Cos on Pedestal).
In a case of the in-phase driving of all elements (++++) an antenna diagram with a broadside main lobe 1 is produced. Another antenna diagram 2 is produced by an alternating in-phase/counter-phase driving of the elements (++−−). This diagram 2 includes two identical main lobes, which diverge by ±30° from the main emission direction of the broadside main lobe 1 . By alternating in-phase/counter-phase driving of the elements (+−+−) two identical main lobes are produced as shown in diagram 3 deviating form the main emission direction of the broadside main lobe 1 by ±60°.
From this variability of the orientation or directionality of the antenna main lobe there results a coverage of a angle area of approximately −70° to +70° in a spatial plane, in the case of the employment of antenna elements with main lobe breadths (broadside) of approximately 30°. The total angle area can thus in this case be divided into five switchable sectors. In advantageous manner this relationship can be realize by means of the arrangement of a planar array, which is comprised of four antenna elements, which are arranged in a row with a separation of 0.54 λ (λ=wave length of the emitted wave) to each other. Therein the antenna elements can be single emitters or also antenna rows.
FIG. 2 shows a schematic circuit diagram for the inventive device. The device is comprised of a 3 dB four grid hybrid junction 4 , two three grid power dividers 5 , a change-over or reversing switch 6 for alternating connection of the input and output of the antenna elements 8 and 9 , the antenna elements (single emitters or lines) 7 through 10 , as well as the connecting lines between the components. The effective connecting line lengths between the antenna elements 7 through 10 and the inputs of the three grid power divider 5 are the same length, in order to take under consideration the influence of the change-over switch. By the connection of the three grid power divider 5 , the inputs of the 3 dB four grid hybrid junction 4 are connected with the three grid power divider 5 with and without a λ/4-detour line. Thereby, at the outputs of the 3 dB four grid hybrid junction 4 , the sums and differences of the input signals can be taped off. This corresponds to a phase-monopulse circuit.
The inventive device can be used for sending as well as for receiving operations. The in-phase selection (++++) of the antenna elements 7 through 10 is therein independent of the position of the change-over switch. The communication between the sender-receiver electronics and the antenna elements 7 through 10 occurs in this case via the sum channel 11 . The in-phase/phase-opposition selection (++−− or, as the case may be, +−+−) of the antenna elements 7 through 10 is on the other hand controlled by the switch 6 . The communication between the sender/receiver electronics and the antenna elements 7 through 10 occurs in both cases of the in-phase/phase-opposition selection via the differential channel 12 . Therein the positioning of the switch 6 into position A results in a selection pattern (++−−) which results in the antenna diagram 2 shown in FIG. 1 . The positioning of the switch 6 into position B subsequently produces the selection signal (+−+−), which produces antenna diagram 3 .
One possibility of an advantageous embodiment of the inventive device is shown in FIG. 3 . The embodiment shown here corresponds essentially to the schematic circuit diagram of the inventive device shown in FIG. 2 , with the difference that here the double switch 6 is realized by two 3 dB hybrid junctions 13 and 14 , two switches 15 operated in synchrony, and two conductor segments 16 and 17 . The two conductor segments 16 and 17 are shown differing in the length, so that the length difference corresponds to an uneven multiple of the half wave length of the waves conductor through the device. The two 3 dB hybrid junctions 13 and 14 are herein switched in series, wherein one output of 13 is coupled directly with one input of 14 , while the coupling of the other output from 13 occurs via be switch 15 and one of the two conductor segments 16 or 17 .
According to the example represented in FIG. 2 , the position of the switch 6 in position A corresponds to a selection pattern (++−−), which results in the antenna diagram 2 represented in FIG. 1 . The position of the switch 6 in position B, which results in a longer conductor path by λ/2 in comparison to switch position A (180° phase shift), produces as a consequence the selection pattern (+−+−), which produces antenna diagram 3 . The switch 6 can be constructed as a simple double switch according to FIG. 3 , which makes it possible to switch between one circuit of the length L and one circuit of the length L+λ/2 (wherein λ corresponds to the half of the operating frequency of the antenna arrangement). On the other hand, it is also conceivable to realize the switch 6 by means of the switching of a 3 dB hybrid junction.
During an operation of a sender/receiver unit generally a determination of the direction of entry of a received wave is of interest, that is, it is to be determined in which of the main lobes of the antenna arrangement the wave would enter. This is above all difficult to determine when, as in the inventive device, the individual main lobes of the antenna arrangement are constructed identically. In order to determine an entry direction, it would for example be possible, according to the phase-monopulse process, to measure the phase angle of the output of the differential channel.
In advantageous manner it is possible also to employ the possibility of the individual control of the inventive device in such a manner that the antenna diagram is deformed by a non-symmetric selection (for example: (+++−)) of the antenna elements 7 through 10 . The entry direction of the received wave can then be determined by a comparison of the change of the received signal at the output of the differential channel with the signal which is received via the undeformed antenna diagram. For producing the non-symmetric switching, (for example: (+++−)), a switchable 180° detour line could in advantageous manner be provided in the input to antenna element 9 . If then this detour line is employed together with the selection according to switch position A then there results the non-symmetric antenna diagram.
It is however also conceivable, to further develop the inventive device in such a manner, that one single or individual antenna element is placed with suitable spacing beside the antenna array, so that in the additive complete diagram of the antenna arrangement one of the two main lobes is completely or partially suppressed. From a comparison of the output signal of the device without taking into consideration the supplemental antenna element, with the additive output signal of the total device, the entry or reception direction of the received signal can be determined. | In order in simple manner to switchably cover a wide angle in sectors using an antenna array with broad main lobe, an antenna elements are so arranged, that the elements can be individually selected, so that some elements of the array can be operated in-phase and other elements operated in phase-opposition relative to each other. In order to determine the entry direction of a received signal, it is possible to operate the antenna array with non-symmetric antenna diagram, or however also to additively influence the symmetry of antenna characteristic by the use of a supplemental receiver element. | 7 |
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a data transmission apparatus that is connected with digital and/or analog signal sources.
In general, when a digital signal is used in data transmission its reliability can be improved with ease by the addition of a so-called error correcting code, such as a cyclic redundancy check code (CRC), a parity code or the like. Also, a bus-line system in which one line can be commonly utilized by a plurality of systems can be effected with ease.
In the case of an analog transmission in which the information is provided by voltage values or the like, there are drawbacks in that attenuation thereof is proportional to the transmission distance and the analog transmission system is susceptible to noise. Also, the analog transmission system cannot utilize means for improving a reliability, such as the CRC code, a parity code or the like. Therefore, the analog transmission system is not too suitable for long distance data transmission. Nevertheless, the analog transmission system can transmit data of a plurality of levels in addition to binary data of "1" and "0" in the digital signal transmission and is considered an effective means in short distance transmission.
The assignee of the present application has previously proposed an apparatus in which a memory integrated circuit (IC) is mounted inside of a magnetic tape cassette used in a VTR and a circuit board having an electrical contact is also formed therein. When such magnetic tape cassette is loaded in the VTR, the contact is brought in contact with a detection terminal of the VTR, so that inherent information relating to in the cassette that is stored in the memory IC (tape length, tape remaining amount, the number of times that the tape has been used, rental tape identity, or other tape information concerning record contents, such as table of contents, etc.) can be read out. Then, such information is displayed and operation of the VTR is controlled accordingly (see Japanese patent application No. 4-165444). In this case, information is read out from the VTR in a digital fashion.
Further, the assignee of the present application has previously proposed an apparatus in which a circuit board having similar contacts formed thereon is mounted on a magnetic tape cassette used in a VTR. When the contacts are short-circuited, opened or connected via resistors, the VTR can determine these conditions of the contacts so that the VTR side can detect and employ various information (tape thickness, kinds of magnetic materials, etc.) inherent in the magnetic tape cassette (Japanese patent application No. 4-209470). That is to say, the information discrimination can be carried out in an analog fashion.
When there are present a magnetic tape cassette from which information must be read out in a digital fashion and a magnetic tape cassette which must be discriminated in an analog fashion, the VTR must discriminate them satisfactorily and read out information from the magnetic tape cassette in a digital fashion or discriminate such magnetic tape cassette in an analog fashion. This requirement for a VTR to deal with tape cassettes in both a digital and analog fashion has presented several problems not only in the design of compatible hardware but, also, in the operating systems that can accept both kinds of data.
Thus, the problem solved by this invention relates to a magnetic tape cassette from which information must be read out in a digital fashion and a magnetic tape cassette which must be satisfactorily discriminated in an analog fashion to thereby carry out the digital reading or analog discrimination.
OBJECT AND SUMMARY OF THE INVENTION
Therefore, it is an object of the present invention to provide a system for transmitting information about the contents of a tape cassette to a video tape recorder that can eliminate the above-noted drawbacks inherent in previously proposed systems.
According to a first aspect of the present invention, there is provided a data transmitting apparatus to which a digital signal source or analog signal source is connected through an arbitrary number of electrical contacts. This apparatus is comprised of means for applying voltages to arbitrary ones of the plurality of contacts via predetermined resistors, comparators or the like respectively connected to the arbitrary contacts through switches for discriminating potentials developed at the arbitrary contacts, and a data processing circuit connected to the arbitrary contacts through the switches, wherein the digital signal source or analog signal source connected to the plurality of contacts is discriminated by using a discriminating signal from the comparators.
According to a second aspect of the present invention, there is provided the data transmitting apparatus described above, which further comprises a detector for detecting the connection of the digital signal source or analog signal source, wherein the switches are switched to the discriminating comparators by a signal from the detector and the switches are switched to the data processing circuit side when the discriminating signal is a predetermined signal.
According to a third aspect of the present invention, there is provided the data transmitting apparatus just described, wherein after the switches are switched to the data processing circuit side, the data processing circuit outputs a predetermined signal and when a predetermined returned signal is not output, it is determined that the analog signal source is connected to the data transmitting apparatus.
According to a fourth aspect of the present invention, there is provided the data transmitting apparatus of the above-described second aspect of the present invention, wherein after the switches are switched to the data processing circuit side, the data processing circuit outputs a predetermined signal and it is determined on the basis of a content of its output returned signal whether the contact or the transmission line is malfunctioning.
According to the present invention, the digital signal source and the analog signal source can be discriminated from each other satisfactorily and possible troubles with contacts or the like can be detected.
The above and other objects, features, and advantages of the present invention will become apparent from the following detailed description of illustrative embodiments thereof to be read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing a circuit arrangement of a data transmitting apparatus according to a first embodiment of the present invention;
FIG. 2 is a table used to explain the operation of the data transmitting apparatus of FIG. 1;
FIG. 3A is a diagram showing an example of a data format of the present invention;
FIG. 3B is a flowchart useful in explaining operation of the data transmitting apparatus of the present invention;
FIG. 4 is a diagram showing a circuit arrangement of the data transmitting apparatus according to a second embodiment of the present invention;
FIG. 5 is a diagram useful in explaining operations of a corresponding VTR;
FIG. 6 is another diagram useful in explaining operation of a corresponding VTR;
FIG. 7 is a diagram showing a circuit arrangement of the data transmitting apparatus according to a third embodiment of the present invention;
FIG. 8 is a flowchart useful in explaining operation of the data transmitting apparatus of FIG. 7;
FIG. 9A is a diagram showing a circuit arrangement of the data transmitting apparatus according to a fourth embodiment of the present invention; and
FIG. 9B is a diagram showing a circuit arrangement of the data transmitting apparatus according to a fifth embodiment of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
In FIG. 1, reference letter A depicts a data transmission apparatus side, that is, a transmitting and receiving apparatus provided in a VTR. Reference letter B depicts a digital circuit board constituting a transmitting and receiving apparatus on which a memory IC serving as a digital signal source is mounted and in which contacts are formed. Further, reference letter C depicts a circuit board constituting a transmitting apparatus which disconnects or connects contacts serving as analog signal sources and which includes resistors. These circuit boards B and C are connected to the transmitting and receiving apparatus A through contacts and signal paths to d.
The circuit board B serving as the digital signal source includes a digital circuit such as a memory IC (not shown) or the like. In the circuit board B, the contact a is connected to a voltage source Vcc and the contact d is connected to ground. The contacts b and c are connected to internal bus lines 21, 22, respectively, that are connected to the memory IC (not shown). A data output field effect transistor device (FET) 23 and a data input buffer circuit 24 are connected to the bus line 21 connected to the contact b. A clock input buffer circuit 25 is connected to the bus line 22 connected to the contact c.
In the circuit board C serving as the analog signal source, the contact a is not connected and the contact d is connected to ground. Further, the contacts b and c are also connected to ground through resistors 31 and 32, respectively, each having an arbitrary resistance value.
For operation with such circuit boards B and C, the transmitting and receiving apparatus A is constructed as follows. As shown in FIG. 1, the contact a is connected to the voltage source Vcc and the contact d is connected to ground. Further, the contacts b, c are respectively connected through predetermined resistors 1, 2 to the voltage source Vcc. The contacts b, c are also connected through respective fixed contacts of change-over switches 3, 4 to a serial data line (SDL) and a serial clock line (SCL) of a data processing circuit 5, respectively. The data processing circuit 5 can be advantageously constructed as a microcomputer.
Further, the contacts b, c are connected through the other fixed contacts of the change-over switches 3, 4 to comparing input terminals of comparators 6, 7 and 8, 9, respectively, Voltage-dividing circuits formed of resistors 10, 11, 12 and 13, 14, 15 are connected to the voltage source Vcc, respectively, and voltages developed at respective voltage-dividing points are connected to reference input terminals of the comparators 6, 7 and 8, 9, respectively. The output signals from the comparators 6, 7 and 8, 9 are supplied to data input terminals ID0, ID1 and ID2, ID3 of the data processing circuit 5.
Accordingly, the contacts b, c are held at potentials of Vcc when the circuit board B in the disabled state is connected, because the FET device 23 and the buffer circuits 24, 25 all become open drains or open collectors and the resistors 1, 2 serve as pull-up resistors.
When the circuit board C is connected, if the resistance values of the resistors 1, 2 are taken as R and the resistance values of the resistors 31, 32 of the circuit board C are taken as either infinity (open), R, or 0 (short-circuit), then the potentials developed at the contacts b, c are set to Vcc, 1/2Vcc, or 0 (ground potential), respectively. If the resistance values of the resistors 10 to 15 are all set to the same value, then the comparators 6, 7 and 8, 9 can judge when the potential is 2/3Vcc or more, which is stated (2) when the potential is 1/3Vcc or more but less than 2/3Vcc, which is state (1) and when the potential is less than 1/3Vcc, which is state (0).
Therefore, according to this embodiment the three above states (2) to (0) can be judged by connecting the change-over switches 3, 4 to the comparators 6 to 9. For example, the nine different states shown in FIG. 2 can be judged. Thus, it is possible to know various information, such as thickness of tape, kinds of magnetic material, etc., inherent in a cassette when the analog circuit board C is connected to the apparatus.
In FIG. 2, when the contacts b, c are both in state (2) it cannot be determined whether the potential is Vcc because the resistance values of the resistors 31, 32 of the circuit board C are both infinity (open) or because the disabled circuit board B is connected to the apparatus. In this case, the change-over switches 3, 4 are respectively connected to the data processing circuit 5 side and the circuit boards B, C are judged according to the following procedure.
FIG. 3A shows an example of a data format that comprises start condition data, a 7-bit slave address, 1-bit read condition data, 1-bit acknowledge data (ACK), 8-bit data, 1-bit not acknowledge data (NACK), and stop condition data.
As shown in FIG. 3B, when the start condition data is output at step [1A] of the transmitting and receiving apparatus A at the data processing circuit 5, the start condition data is recognized at step [1B] at the circuit board B side. When the slave address is output at the next step [2A], the slave address is input at step [21B]. It is determined in the next step [22B] whether the address is the address of the circuit board B. If the address is not the address of the circuit board B as represented by a NO at step [22B], then the processing returns to step [1B].
If it is determined at step [22B] that the address is the address of the circuit board B, then the acknowledge (ACK) low potential is output at step [3B]. It is determined at step [3A] whether the acknowledge (ACK) is at low potential and if it is not at low potential, the circuit board C is connected and it is determined that the resistance values of the resistors 31, 32 are both infinity (open) and the potential is Vcc. Then, operation is ended.
After the acknowledge is output at step [3B], predetermined 8-bit data, for example, "00000000", is output at step [4B]. The 8-bit data is input at step [41A] and it is determined in step [42A] whether or not the input data is correct. If the data is correct, then the NACK high potential is output at step [5A]. Further, it is determined in step [5B] whether or not NACK is at high potential. If it is not at high potential, then the processing returns to step [4B].
After NACK is output at step [5A], the stop condition data is output at step [6A], and other processing is executed at step [7A]. When the stop condition data is recognized at step [6B], the termination processing is executed at step [7B] and then the processing returns to step [1B].
Therefore, the selected one of the circuit boards B and C that is connected to the apparatus can be determined. When the circuit board B is connected to the apparatus, the change-over switches 3, 4 are fixed to the data processing circuit 5 side, respectively, and data is input and output in a method according to ordinary bus-line processing or the like. If it is determined in step [42A] that the input data is not correct, then the NACK high potential is not output, so that the 8-bit data is repeatedly output in step [4B]. If that data is repeatedly output an arbitrary number of times, it is determined that a malfunction of the contacts or of the transmission line has occurred. Then, an alarm or the like is generated.
As described above, according to this embodiment the digital signal source and the analog signal source can be discriminated satisfactorily and a malfunction of the contacts or of the transmission lines can be detected.
FIG. 1 shows a system using four contacts a, b, c and d, and FIG. 3 shows an example of a general purpose bus protocol for microcomputer using two lines of SDL and SCL. According to this protocol, a master CPU (not shown) supplies a slave address to the slave CPU, slave memory, or the like through the SDL line and the slave side acknowledges the slave address and returns the acknowledge to the master side. Thus, this protocol plays the role of an ordinary chip select (nCS), where n represents a negative logic.
Therefore, the three lines SDL, SCL, and nCs that are normally required to effect communication can be cut down to two lines, represented by SDL and SCL.
The present invention can also be applied to a system using a more general chip select and, as shown in FIG. 4, the transmitting and receiving apparatus A is connected through five contacts a, b, c, d, e to the digital circuit board B and to the analog circuit board C. The contact a is connected to the voltage source Vcc, and the contact e is connected to ground GND. The contacts b, c, d are connected to the lines SDATA, SCK, nCS, in that order. In accordance therewith, there are required three pull-up resistors 41, 42 and 43.
A microcomputer that is typically utilized in the VTR generally includes a serial transfer I/O port. The inside system of the VTR is arranged by using such serial transfer I/O port and FIG. 5 shows such internal system of the VTR.
Referring to FIG. 5, as serial transfer terminals there are provided a serial input terminal SIN, a serial output terminal SOUT, and a serial transfer clock output terminal SCLK. In order to select an equipment on which the serial transmission and reception are effected, the chip select signal (nCS) is output from the I/O port of the microcomputer 50. The three serial transfer terminals SIN, SOUT, SCLK are typically used in the internal bus of the VTR.
As shown in FIG. 5, input data supplied from the SIN terminal is converted into parallel data by a serial-to-parallel (S/P) converter 51. At that time, there is generated a reception interrupt signal (RXT INT) 54 indicative of the reception of data. Then, the microcomputer 50 executes the data reception processing.
When data is transmitted, output data is set in a parallel-to-serial (P/S) converter 52. When the data transfer is ended, a transmission interrupt signal (TXT INT) 55 is generated to enable the microcomputer to know the end of transfer. The important transfer clock is generated by a clock generating circuit 53 and fed to convertors 51, 52 and at the output clock SCLK.
According to the serial transfer I/O port, the transmission and reception of data can be processed automatically by the microcomputer 50. In addition, the interrupt occurs in the data transmission and reception, so that the work of the software can be reduced considerably. This function is indispensable to a multi-microprocessor system, that is, a system for controlling a number of microcomputers in linkage, that is generally utilized in the VTR. For this reason, the serial transfer I/O port is connected to the internal bus of the VTR.
FIG. 6 shows an example of the multi-microprocessor system typically utilized inside the VTR, which a microcomputer that generally controls the mode is operated as a main CPU 56 to control the internal bus 57, that is, the microcomputer has an initiative for the clock SCK and the chip select nCs. Other microcomputers are operated as sub CPUs 56-1, 56-2, . . . 56-n to effect the processing organically under the control of the main CPU56. The number of sub CPUs, 56-n, is generally different depending upon the VTR.
Considering the case in which the data transmission apparatus shown in FIG. 4 is applied to the internal bus of the VTR. In the case of the system that is connected to the outside through contacts, such system must be protected from static electricity of high voltage or the like. When the internal bus is merely connected to the contacts, if some trouble occurs, then all CPUs, etc., that are connected to the internal bus are damaged fatally. To obviate the aforesaid defect, the internal bus is connected to the contacts through buffers. With this arrangement, only the buffers are damaged even if trouble occurs.
FIG. 7 shows such an example of the data transmission apparatus according to the present invention, in which buffers 74 through 77 function to protect CPUs or the like from being damaged. The reason that the direction of the buffer 74 is opposite to that of the other buffers 75 to 77 is to collect two lines DIN, DOUT as one line SDATA. The direction of data is switched by the main CPU56 shown in FIG. 6. When analog data is read, the internal buses 81 are connected through buffers 78, 79, 80 to voltage comparators corresponding to the comparators 6, 7, 8, 9 of FIG. 1. Outputs of these voltage comparators are supplied to the I/O port of the main CPU. The buffers 74 to 77 and the buffers 78 to 80 form two groups that function as the switches 3 and 4 in the embodiment of FIG. 1.
When the digital circuit board B and the analog circuit board C in FIG. 7 can be connected to the internal buses 81 of the VTR, the main CPU can control the digital circuit board B and the analog circuit board C in a manner similar to controlling other sub CPUs or the like connected to the internal buses. Therefore, the overall software arrangement can be simplified and debugging can be made easy.
In the processing procedure of this system initially, signals are switched to the side of the buffers 78 to 80 and voltage levels are recognized by the voltage comparators. The comparison of the voltage levels is the exactly the same as that of FIG. 2, to which contact d is added, though not shown.
That is to say, similarly to the contacts b and c provided when the above-mentioned circuit board C is connected, the states of (2), (1), (0) in the contacts b, c, and d can be discriminated. Thus, twenty-seven (3×3×3) different states can be discriminated, thereby making it possible to determine information, such as tape thickness, kinds of magnetic material, tape grade or the like, inherent in the magnetic tape cassette, for example, when the circuit board C is connected.
Nevertheless, in FIG. 7, when the contacts b, c, and d are all set in the states (2), it cannot be determined whether the resistance values of the resistors within the analog circuit board C are infinite (open) and held at Vcc or held at Vcc because the inoperative digital circuit board B is connected. Accordingly, in this case, the signals are switched to the side of buffers 74 to 77 and the circuit boards B and C are discriminated by the following procedure.
More specifically, in FIG. 8 the buffer 74 is set in the active mode and the buffer 75 is set in the inactive mode, whereby the SDATA is switched to the DIN direction of the internal bus in step [81]. Then, nCS=low potential is established in step [82] and the 8-bit data (01010101) of a predetermined memory address is read out in step [83]. If the data thus read is 11111111, then it is determined that the circuit board is the analog circuit board C.
If the data thus read is not 01010101, then it is determined in step [85] that there is some trouble with the contact or the like. If the data thus read is 01010101, then it is determined that the circuit board is the digital circuit board B. To make sure of it, steps [86], [87] and [88] are executed, that is, arbitrary data is written in another address and the data thus written is read out to examine whether the data thus read is a correct value.
If the value of the data thus read is correct, then it is determined that the circuit board is the normal digital circuit board B. Also, it can be understood that the respective lines SDATA, SCK and nCS, the respective contacts and the buffer are operated correctly. If the value of the data thus read is not correct, then it is determined that the digital circuit board B or the like is in trouble. If reading and writing of data are carried out a plurality of times, then a reliability of judged results will be increased.
As described above, according to this embodiment apparatus, the digital signal source and the analog signal source can be discriminated from each other satisfactorily, and also any trouble with the contacts or the like can be detected.
In the above-mentioned apparatus, under the condition that the contacts b, c or contacts b, c, d are all in the so-called state (2), the circuit boards B, C must be discriminated from each other. Also, under this condition, the contacts b, c or contacts b, c, d of the circuit board C are all made open and the cassette body does not need any circuit arrangement or the like. Accordingly, if this state is set to the most standard cassette information, then a manufacturing cost of the most standard cassette can be made low.
Further, in the above-mentioned apparatus the connection upon insertion of the cassette of the circuit boards B, C is detected by a system control circuit (not shown) or the like. If the change-over switches 3, 4 are respectively switched to the comparators 6 to 9 by this detected signal in FIG. 1 and the signal is switched to the buffers 74 to 77 by this detected signal in FIG. 7, then the succeeding processing can be executed smoothly.
In FIG. 3, because the acknowledge ACK is returned from the circuit board side as an answer, it is determined on the basis of this answer whether or not the digital circuit board is in the normal condition. In FIG. 8, such an answer is not obtained, so that the data is written in another different address and read out therefrom so as to check the state of the digital circuit board. Needless to say, if the steps [85] to [88] in FIG. 8 are added to the processing in FIG. 3, then it can be determined more accurately whether the digital circuit board is in the normal condition.
More specifically, the judgement of the analog circuit board C in step [3A] in FIG. 3B and step [4] in FIG. 8 must be carried out with care. That is, if any one of the contacts is deformed and is therefore not correctly brought in contact with the analog circuit board C, then a correct voltage value cannot be read out, that is, voltage levels at the contacts b, c or contacts b, c, d cannot be judged accurately. From this standpoint, some collective countermeasures, such as increasing the reliability of the mechanism or the like must be taken and also, it is important to set the decision making based on the voltage level so as to error on the side of safety.
One-chip microcomputers incorporate therein an A/D converter at the input and output section thereof so as to form the so-called analog input and output. In this arrangement, the terminal thereof can be switched as the A/D converter of analog input or input and output terminal of digital signal in use. Thus, the functions of the switches 3, 4 in FIG. 1 can be realized by software.
When the apparatus shown in FIG. 1 utilizes such one-chip microcomputer, such as shown in FIG. 9A, the contacts b, c are directly connected to an input and output section I/O of the one-chip microcomputer 50 and resistors 1, 2, which as pull-up resistors when a digital signal is input and also serve as voltage-dividing resistors when an analog signal is input, are connected to the contacts b and c, thereby making it possible to execute a function similar to the above function.
FIG. 9B shows a circuit arrangement in which the above-mentioned function is realized relative to the circuit of FIG. 7. As shown in FIG. 9B, outputs of the buffers 78, 79, 80 are connected to an I/O port of a main CPU 81 which is one-chip microcomputer having an A/D converter input and output function. The switching function can be realized by the buffers 74 to 77 and the buffers 78 to 80. In this example, the buffers cannot be omitted because it is dangerous if the internal bus of the VTR is directly connected to the terminals. Also, abnormal communication must be avoided when the resistors are directly connected to the bus line under the condition that the analog circuit board is connected.
In the case of FIG. 9A, the one-chip microcomputer 50 also provides the buffer function, so that if high-voltage static electricity is applied to the contacts or the like, then only the one-chip microcomputer 50 is damaged and the other circuits are prevented from being damaged.
Further, in this case, the A/D converter at the input and output section has 8-bit=256 resolution, for example, however, when the above-mentioned apparatus is applied to the magnetic tape cassette of the typical VTR, for example, it is desirable to use inexpensive resistors of low accuracy as the resistors 31, 32 on the circuit board C. Also, considering that resistance values change due to moisture on the resistors or the like, proper resolutions are more than 2/3Vcc, which is state (2), more than 1/3Vcc and less than 2/3Vcc, which is state (1), and about less than 1/3Vcc, which is state (0). Therefore, when the above 8-bit microcomputer is used, if the value that results from A/D-converting the input potential is classified into the range of states (2) to (0) and the input value is judged, then the similar function to the above can be realized.
The present invention can be applied to the case that the SDATA line in FIG. 7 is divided into two lines DIN and DOUT of the internal bus. In this case, there will be six contacts provided.
Furthermore, in the circuit shown in FIG. 1 and the protocol shown in FIG. 3, a 5-contact system in which contacts are provided only for the analog input and output may be considered. This method is similarly effected in FIG. 7 and the number of contacts can be increased freely. At any rate, a concept on the fundamental portion can be made by the present invention.
According to the present invention, the digital signal source and the analog signal source can be discriminated from each other satisfactorily and any trouble with the contact or the like can be detected. | A digital signal source and an analog signal source, such as might be contained in a video tape cassette, can be discriminated from each other in a video tape recorder by providing only a minimum of electrical contacts. A first contact is connected to a voltage source and a fourth contact is connected to ground, while second and third contacts are connected through resistors to the voltage source. The second and third contacts are respectively connected through fixed contacts of two change-over switches to a serial data line and to a serial clock line of a data processing circuit, and those contacts are also respectively connected through the other fixed contacts of the change-over switches to comparing input terminals of a group of comparators. A voltage-dividing circuit formed of resistors is connected to the voltage source and the voltages developed at respective voltage-dividing points are supplied to reference input terminals of the comparators and output signals from the comparators are supplied to data input terminals of a data processing circuit in the video tape recorder. | 6 |
BACKGROUND AND SUMMARY OF THE INVENTION
The invention pertains to the processes and materials used to reduce the reflection of electromagnetic waves off a wall of a structure or infrastructure.
It is more specifically designed for a process to fasten an intrinsic element absorbing electromagnetic waves onto a wall of a structure, moving or not, or an infrastructure.
There are known methods used to reduce the electromagnetic wave reflectivity of a structure or infrastructure and thereby reduce their radar signature. These methods are essentially and principally comprised of camouflage covers, such as nets covering the structure or infrastructure. Thus, a net made of material that absorbs electromagnetic waves is used, and this net is attached to the structure, for example, with fastening straps or cables. Such a method can be quite cumbersome to use, particularly for structures or infrastructures containing moving parts.
Other methods proposed were the use of rigid panels including a synthetic resin as the matrix with an imbedded element that absorbs electromagnetic waves. However, although perfectly suited to make infrastructures or to protect flat surfaces and simple shapes, these panels are very difficult to use for the protection of moving structures, or non-flat surfaces or complex shapes. Moreover, any damage to part of the panel is very difficult to repair and most often requires the replacement of the entire panel.
To correct these drawbacks, the invention proposes a process to fasten an intrinsic element absorbing electromagnetic waves such as a net, for example, onto a wall of a structure or infrastructure which will enable it to be attached simply and reliably to any surface of any shape, even by unspecialized persons, and to easily repair damaged parts with a simple sealing or filling of these parts.
Accordingly, the invention is designed for a process to fasten an intrinsic element absorbing electromagnetic waves onto a wall of a structure or infrastructure, characterized as follows in that it consists of:
applying a coating onto a surface of the aforesaid wall by means of a syntactic foam that is transparent to electromagnetic waves and that has the rheological properties of a mastic;
placing the aforesaid intrinsic absorbent element into or onto the aforesaid syntactic foam coating;
letting the aforesaid syntactic foam harden.
Of course, for the coating to adhere to the wall, it is usually necessary to clean the surface of the wall, namely by degreasing or sand blasting, for example; these operations are those that are normally conducted to prepare a surface prior to applying a coat of paint or applying any type of coating.
The syntactic foam is a composite material including as its matrix, a resin such as an epoxy resin, polyester, phenolic, silicone, for example, and a volume-reduction filler consisting of hollow or porous microspheres, such as, for example, microscopic particles of glass, plastic, zeolite, vermiculite, and having a low density.
BRIEF DESCRIPTION OF THE DRAWING
The single figure represents the variation of the reduction of reflectivity of a flat surface as a function of frequency of the electromagnetic waves.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
These different syntactic foams that may be used for the invention shall preferably be those with a density less than or equal to 600 kg/m 3 .
Preferably, the matrix of the syntactic foams suitable for the invention is made of a resin polymerizing at ambient temperature, and most advantageously at a temperature between approximately 18° C. and approximately 30° C. By selecting this resin, the coating can be hardened without requiring a thermal process and a costly facility.
In addition, to obtain (working) pot lives that are compatible with implementation of the process, it is preferable to use a system with two components, a component A containing the resin filled with the microscopic particles and various additives, if any, and a component B containing the resin hardening agent.
The systems suitable for the invention are those that offer a (working) pot life on the order of approximately 2 hours or longer pot life. In effect, this length of time is long enough for an application of the coating onto the wall and setting the absorbing element before the syntactic foam hardens.
The duration of polymerization of the syntactic foam is not critical, but the preferred systems have a polymerization duration on the order of 24 to 48 hours at ambient temperature.
As additives, the following can be used, for example, dyes, texture agents, structural fillers that do not conduct electricity, viscosity modifiers, or agents that promote bonding.
Moreover, the syntactic foams suitable for the invention must be transparent to electromagnetic waves, and therefore possess the following dielectric properties:
permittivity less than 2
dielectric loss factor less than 5×10 -2
Any element absorbing electromagnetic waves that is intrinsic, i.e., which can itself form an absorbent surface capable of reducing the reflectivity of a wall, is suitable for the invention. The following can be listed as absorbent elements marketed in the form of nets, felt, fabric, reticulate foam, or unwoven fabric. As an example, there are the absorbent nets sold by the company PLESSEY under the names ENA-1, or LAO.
The wall onto which the absorbent coating is applied must reflect electromagnetic waves. However, this property can be obtained simply with a layer or a reflecting element forming this wall, specifically in the case of a composite wall, or, for example, with a reflecting coating alone.
Hence, the layer or reflecting element may be, for example, a composite material such as carbon-epoxy or metallic composites, metallic fabrics, metal-resin composite, or a reflecting paint.
According to the invention, it is possible, preferably after hardening the syntactic foam, to coat the surface of the resultant coating with paint or any other protective layer.
The invention is especially useful to make coatings that absorb electromagnetic waves with a frequency of over 2 GigaHertz (GHz), preferably between 6 GHz and 100 GHz, and most advantageously between 6 and 40 GHz.
According to another characteristic of the invention, an additional layer of syntactic foam may be applied after setting the intrinsic element, thereby completely embedding that element in the syntactic foam. This additional layer is also designed to protect the intrinsic element from exterior forces.
The thickness of the layer or layers of syntactic foam is not critical, but should preferably be as thin as possible, to be compatible with the conditions of use of the treated structure.
To improve the adherence of the syntactic foam onto the wall to be coated, it is possible to either add a bond-promoting additive to the foam, or to coat the surface of the wall with an adhesive called a "primary" consisting, for example, of an epoxy resin.
The invention will be better illustrated in light of the example below and the attached figure both given on an indicative basis only, and other advantages, details, and purpose of the invention will appear more clearly.
The coating of a metallic wall is performed with an element absorbing electromagnetic waves, according to the invention process.
For this, after sand blasting and cleaning, specifically degreasing the wall exposed to the electromagnetic waves, this surface is coated with a thin layer of adhesive, an epoxy resin: the resin Redux 410 sold by MAPROCHIM.
In a second phase, a syntactic foam is prepared by mixing the two components of the foam with epoxy resin matrix and glass microscopic particles marketed by the company Hexcel, under the name "Rezomix 114/L"
______________________________________component A: 100 parts by weightcomponent B (hardening agent): 40 parts by weight______________________________________
A paste is obtained with viscosity ranging between 100 P and 200 P, density on the order of 58 kg/m 3 . The pot life at 20° C. of the resulting mixture is on the order of 5 hours.
This paste is applied to the surface of the wall by any customary processes, and namely the technique of base coating the wall. A net absorbing electromagnetic waves is then placed onto the surface of the syntactic foam already applied. This net is sold by the company Plessey under the name ENA-1. After this operation, a new layer of syntactic foam is applied following a technique similar to that used for the application of the first layer.
It is then left to harden at ambient temperature (20° C.) for 48 hours.
The effectiveness of the coating made in this manner is tested by measuring, at different frequencies, the reduction of reflectivity of the wall compared with a non-coated metal. The measurements obtained are illustrated in the single figure which represents the variation of the reduction of reflectivity Drefl of a flat surface in dB as a function of frequency F of the electromagnetic waves expressed in GHz.
The process of the invention is simple to perform and does not require any particular technical know-how on the part of the person performing the coating.
Moreover, since the syntactic foam can be obtained by a simple mixture of two components, this coating can be done anywhere and does not require any special equipment.
In addition, if part of the coating is damaged, it can be easily repaired by sealing or puttying of the damaged part-this repair can even be performed by an unskilled person.
The coating process of this invention, in addition to providing the property of reducing reflectivity of the wall, also offers a heat-insulating coating.
It is also clear that it is possible to coat any surface of any shape because of the use of a paste or mastic. This results in the capability of an unskilled person to perform the coating operation without special equipment, and also the mobility or the use of the coated structure is not affected. Moreover, since a syntactic foam is used, this coating does not entail an overloaded weight for the structure. | The invention pertains to a process to fasten an intrinsic element absorbing electromagnetic waves onto a wall of a structure or infrastructure.
The process of the invention consists of coating a surface of a wall of a structure by means of a syntactic foam with the rheologic properties of a mastic and being transparent to electromagnetic waves, then placing an element absorbing electromagnetic waves into or onto the syntactic foam coating, and letting the syntactic foam harden. The process can be used to place an element absorbing electromagnetic waves onto surfaces of any shape and in a simple manner without requiring special equipment. | 7 |
This application, filed Sep. 5, 1997, is a continuation of U.S. application Ser. No. 08/253,896, filed Jun. 3, 1994, now abandoned. Ser. No. 08/253,896 is a continuation of Ser. No. 08/027,273, filed Mar. 5, 1993 now abandoned, which is a continuation of Ser. No. 07/464,700, filed Jan. 16, 1990, now abandoned; Ser. No. 07/464,700 is a continuation of Ser. No. 07/370,244, filed Jun. 22, 1989, now abandoned, and of Ser. No. 07/336,563, filed Apr. 10, 1989, now abandoned, which is a continuation of Ser. No. 07/127,145, filed Dec. 1, 1987, now abandoned; Ser. Nos. 07/370,244 and 07/127,145 are both continuations-in-part of parent Ser. No. 07/099,368, filed Sep. 21, 1987, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to improved impact absorbing compressible composites. These composites can be shaped into smooth compound curves and find application wherever high efficiency impact absorption is called for such as in athletic wear, in seating systems, in vehicle interior padding materials and the like.
2. Background Information
There is a well-recognized need for high performance materials for spreading or absorbing impacts. In recent years, athletes, athletic equipment manufacturers and sports medicine professionals have recognized the need for improved impact absorbing materials in athletic equipment. These materials find application as heel pads and foot sole pads in shoes to absorb the shock of foot strike and as cushioning points under football or hockey pads such as shoulder pads, thigh pads, hip pads and the like to name but a few typical applications. Similar needs may be found in seating systems and in vehicle interiors, to name but a few representative fields in which impact absorption is a major interest.
One common approach to impact absorption in the past has involved using felts or blocks of a soft padding material. Padding materials known heretofore include cotton padding, horsehair padding, foam rubber, foamed plastics, sponge rubber and the like. In these designs, the inherent resilience of the padding material is employed to absorb and disperse the applied impact. These designs have the disadvantage that they often “bottom out” or fully compress on severe impacts of the type regularly encountered during use such as in athletic equipment or in vehicle interiors and thus provide minimal protection. When made thicker to avoid this problem, they become cumbersome and can interfere with the design of the article being padded, and in the case of athletic equipment can interfere with the wearer's freedom and performance.
Impact absorbers have also been proposed which employ fluid-filled bladders such as cushioning air sacks These devices rely upon the compressibility of the enclosed fluid to provide the desired shock absorbing. In some embodiments of these devices, the fluid is fully enclosed and can not escape. In others, the fluid is gradually and controllably forced out of the bladder during the impact with the rate of release being selected to prevent exhaustion of the fluid during the impact event. While effective as shock absorbers, these devices can have the failing of ballooning or otherwise expanding in one region when another region is being compressed. This can lead to discomfort or at minimum give an unnatural or unstable feel to the user. In the case of footwear, this problem can lead to an unstable foot plant with increased opportunity for injury. Another issue with this type of pad has related to problems in forming shapes based on compound curve and to retaining structural integrity with the above-described ballooning.
Representative patents in the field of shock absorbing or impact absorbing devices include U.S. Pat. No. 4,513,449, SHOCK ABSORBING ATHLETIC EQUIPMENT; U.S. Pat. No. 4,370,754, VARIABLE PRESSURE PAD; U.S. Pat. No. 4,453,271, PROTECTIVE GARMENT; U.S. Pat. No. 4,217,705, SELF-CONTAINED FLUID PRESSURE FOOT SUPPORT DEVICE, all issued to Donzis, U.S. Pat. No. 4,446,634 for FOOTWEAR HAVING IMPROVED SHOCK ABSORPTION; U.S. Pat. No. 4,397,104 for INFLATABLE SOLE-SHOE; U.S. Pat. No. 2,863,230 for CUSHIONED SOLE AND HEEL FOR SHOES; U.S. Pat. No. 4,229,889 for PRESSURIZED POROUS MATERIAL CUSHION SHOE BASE; U.S. Pat. No. 4,637,716 for METHOD FOR MAKING ELASTOMERIC SHOE SOLES; U.S. Pat. No. 4,635,384 for FOOTWEAR SOLE; U.S. Pat. No. 4,610,099 for SHOCK-ABSORBING SHOE CONSTRUCTION; and U.S. Pat. No.4,571,853 for SHOE INSERT.
It is an object of the present invention to provide an improved impact absorbing composite. It is desired that this composite provide superior shock absorbing performance and also be capable of being formed into complex compound curve shapes, be durable and hygieiic.
STATEMENT OF THE INVENTION
An improved impact absorbing composite has now been found. This composite is capable of dispersing and absorbing impacting forces with high efficiency. The composite is characterized by a structure including a flexible plastic wall (enclosure) defining an internal cavity. This flexible enclosure is made of a material that is generally impermeable to air and is capable of having its internal pressure changed. The internal cavity of the enclosure is filled with a foam core. This core is held in place by the cavity walls. Importantly, the core is intimately adhered (glued, bonded or the like) on substantially all of its external surfaces to the internal surface of the cavity. In preferred embodiments, the wall and the core are prestressed by one another. That is, the core presses out against the wall and the wall pushes in against the core. The intimate adherent contact between the foam core and the outer wall gives rise to an unexpected degree of product integrity and unexpectedly superior impact absorbing capabilities.
In preferred embodiments, the composite has a valve or fitting communicating with the cavity so that the pressure within the cavity can be altered. This permits the composite to be adjusted to accommodate varying impacts. The invention can thus include in combination such a composite together with a device for pressurizing its cavity.
Also in preferred embodiments, the foam core is an open-celled foam or a reticulated foam so that the pressure within the core is uniform. Urethane polymers have been found to be excellent for forming the cavity and the foam and are preferred materials of construction.
In other aspects, the composites of the invention can employ cores having a plurality of different foams arranged parallel or perpendicular to the impact direction. This permits differing densities and impact resistances to be present at different positions on the composite. The impact absorbers of this invention can be used in conjunction with other materials or layers including without limitation, cosmetic or hygienic overlayers, other shock-absorbing layers or the like.
In yet another aspect, this invention provides a variety of methods for fabricating these composites. All of these methods are characterized by creating an adherent bond between the foam core and the outer layer and by pressurizing the core to a value effective to provide efficient impact absorption.
One such method involves shaping the wall surface to create a cavity, sizing and shaping the foam core so as to fully fill the cavity and preferably prestress the wall and core, adhering and enclosing the core within the cavity and adjusting the pressure within the cavity to a value effective to provide efficient impact absorption.
Another fabrication method involves shaping the wall surface to create a cavity, sizing and shaping the core so as to partially fill the cavity, placing the core within the cavity forming an elastomeric foam and preferably an open-celled or reticulated foam in situ within the cavity so as to fill the space between the preshaped foam and the cavity wall and to adhere the cavity wall to the core and preferably prestress the wall and core, and adjusting the pressure within the cavity to a value effective to provide efficient impact absorption.
Yet another fabrication method involves shaping the wall surface to create a cavity, forming a cavity-wall-adherent open-celled or reticulated foam core in situ within the cavity so as to fill the cavity and preferably prestress the wall and core, and adjusting the pressure within the cavity to a value effective to provide efficient impact absorption.
A further fabrication method involves sizing and shaping the foam core, forming the outer wall in situ around and adherent to the foam core such as by shrinking a film a core-adherent material around the core or by applying a layer of uncured wall material, such as a solution of wall-forming polymer, around and adherent to the core and then curing the uncured wall material, thereby creating a cavity enclosing and preferably prestressing the core, and adjusting the pressure within the cavity to a value effective to provide efficient impact absorption.
The present shock absorbing composites can be employed in a wide range of applications. One excellent application is as heel pads and/or sole pads for shoes, especially sport shoes, where they serve to absorb foot strike impact with high efficiency.
The composites of this invention are characterized by being easily formed in compound curve forms, by being very light weight and by being hygienic. They are further characterized by being adjustable in pressure, and thus in impact cushioning capacity. This permits them to serve in a wide range of applications with widely variable impacts.
DETAILED DESCRIPTION OF THE INVENTION
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be described herein with reference being made to the accompanying drawings. Where practical in the drawings, a common reference numeral is used for the same part when it appears in more than one FIG IN the drawing:
FIG. 1 is an exploded perspective view of the components of an impact absorber of this invention;
FIG. 2 is an cut away cross-sectional view of a shock absorber of this invention;
FIG. 3 is a partially schematic cross sectional view of an impact absorbing heel pad not embodying this invention. This heel pad has a wall defining a pressure-tight cavity but does not have a foam core adhered to and filling its inner surface. This figure illustrates the flaw in this design that an impact can be absorbed but at the same time ballooning occurs;
FIG. 4 is similar to FIG. 3 but illustrates that with the present invention ballooning is prevented;
FIG. 5 is a perspective view of an alternative foam core for use in this invention. This core has a plurality of differing compression strength foams arranged parallel to the impact force;
FIG. 6 is a cut away cross-sectional view of another alternative embodiment of the impact absorber of this invention in which the wall material defining the cavity is further shed to provide a supportive column;
FIG. 7 is another cross sectional view of the absorber shown in FIG. 6 taken along line 7 - 7 ′;
FIG. 8 is an exploded perspective view of the components of the absorber of FIGS. 6 and 7;
FIG. 9 is a perspective view of an alternative embodiment of the impact absorber of this invention. This embodiment employs a core which has a plurality of differing compression strength foams arranged perpendicular to the impact force;
FIG. 10 is phantom top view of a core configuration for use with closed cell foam materials;
FIG. 11 is a cross sectional view of the core shown in FIG. 10 taken along line 11 - 11 ′;
FIG. 12 is a phantom top view of another core configuration for use with closed cell foam materials;
FIG. 13 is a cross sectional view of the core shown in FIG. 12 taken along line 13 - 13 ′;
FIG. 14 is a cut away cross sectional view of a shoe containing a shock absorber of the present invention and additionally having a pump for pressurizing the core of the absorber;
FIG. 15 is a cross sectional view of an automotive dash board incorporating an impact absorber of this invention;
FIGS. 16 and 17 are two views of an additional representative application or the shock absorbers of this invention as a foot pad;
FIG. 18 is a perspective view of a shoulder pad under pad application or the shock absorbers of this invention; and
FIGS. 19 and 20 are graphs illustrating the effectiveness of the impact absorbers of this invention and their adaption to various body weights and to various impacts.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2 in more detail, these figures illustrate an impact absorber 10 . Impact absorber 10 includes a foam core 11 and top and bottom wall sections 12 and 14 which when joined define a cavity 15 . A layer of adhesive 16 is present between essentially all of the inner surface of cavity 15 and the outer surface of foam core 11 . This layer is shown on core 11 but could as well be on the inside surface of the wall or on both the core and the wall as desired. When wall sections 12 and 14 are joined, the cavity which they define is pressure tight. It is possible to equip the impact absorber with a valve or fitting such as valve 16 . Valve 16 is a “Halkey-Roberts” type urethane valve which is shown in FIG. 1 in its pre-assembly form. After incorporation, the top end of valve 16 is cut off flush with the surface of the shock absorber as shown in FIG. 2 . Any equivalent form of valve or pressure control aperture can be used, if desired. This valve allows the pressure in the interior (cavity 15 ) of the impact absorber to be adjusted, as desired, by adding or removing fluid from the cavity.
The outer wall of the impact absorber is formed of flexible plastic. The materials used to form the wall can be selected from the film-forming flexible plastics. Virtually any plastic can be used so long as it is resistant to bacterial attack, flexible and shapable into the forms and configurations desired. Useful film-forming plastics include poly(urethane)s both of the poly(ether) and the poly(ester) form, poly(ester)s such as poly(ethylene terphthalate), flexible poly(vinyl)s, elastomeric poly(olefin)s such as poly(isoprene), poly(isobutylene), and neoprene, low density poly(ethylene)s and the like.
In the embodiment shown in FIGS. 1 and 2, the outer wall is preshaped into the desired configuration and then the foam core is adhered to it. In another embodiment, the outer wall can be formed around the foam core. One way to accomplish this is to use a liquid polymer precure solution or suspension which is applied to the outer surface of the core and then cured. Another way to accomplish this is to use plastic sheet stock and laminate it to the core or shrink it around the core. In any of these alternative modes of construction, it is essential that there be a strong adherent bond between the wall and essentially the entire outer surface of the core.
Of the plastics useful in forming the films, preference is given to the flexible poly(urethane)s because of their ready availability. These materials are available from J. P. Stevens Company and Deerfield Urethane,Inc., to name but two regular suppliers. Representative useful plastic films include the Deerfield “Dureflex” poly(urethane) films. These materials can be preformed, as in FIGS. 1 and 2 or they can be used as stock goods. When a liquid is used to apply the outer wall, it is typically a solution of a prepolymer or resole resin. Vinyl films can be used in this application. A typical vinyl film is the vinyl adhesive sealant produced by W. R. Grace and marketed by Eclectic Products as Eclectic 6000 adhesive sealant. These materials are solvented in halocarbons such as perchloroethylene and the like. A preferred liquid coating is based on the polyurethanes. Again, the nonrigid urethane polymers are preferred. The solutions known in the art for forming flexible urethane films are very suitable for this application. Typical urethane polymer solutions include the reaction product of a diisocyanate such as toluene diisocyanate or hexamethylene diisocyanate with a polyol such as a polyether polyol. These reaction products are commonly produced in a mixed solvent system such as a polar solvent (for example, Butyl Cellosolve, Cellosolve Acetate, butyl Carbitol, or diacetone alcohol or the like) in combination with an aromatic solvent such as toluene, benzene, or hydrocarbon distillate fractions heavy in aromatics and having a boiling range in the range of from about 140 to 240° C. This outer wall, when applied as a liquid can be dried (solvent removed) and cured by the application of heat and/or the application of a curing catalyst such as an amine. Other curing modalities such as photocuring can be employed as well, if appropriate. The liquid wall-forming compositions can contain plasticizers and builders and the like, if desired. The particular conditions used for forming the outer wall are conventional for processing polymers such as the urethanes which are preferred and are known to those of skill in the polymer arts.
The outer wall, whether supplied as a preformed structure, a cured liquid overcoat or a shrunk or adhered layer of stock goods is commonly from about 1 to 200 mils in thickness with thicknesses in the range of from about 2 to 50 mils being preferred and excellent results being attained with thicknesses of from about 3 to about 35 mils.
The core of the impact absorber is a foam. This foam is preferably an open-celled foam, that is a foam in which the various cells are in communication with each other and with the outer surface of the foam. Similar properties are achieved with a reticulated foam, that is a foam which has been treated to break down membranes which separated various cells. Foam rubber, foamed latex, vinyl foams and the like can be used. The preferred foam material for use in the core is poly(urethane) foam. Representative foams include the “Ensolite” foams sold by Uniroyal Plastics Co., Inc. and the flexible urethane foams sold by the E. R. Carpenter Company.
Typical densities for the foam core range from between about 0.5 to about 15 pounds per cubic foot.
Preferred foam densities are from about 2 to 10 pounds per cubic foot.
It will be appreciated that because the foam core is adhered to the outer wall it is in effect a structural member. The adhered foam serves to prevent the ballooning of the device as previously described. This duty puts strain upon the foam of the core. If the foam separates under this strain it can result in a loss of integrity of the device. With this potential problem in mind, it is possible to reinforce the foam by including filaments or fibers or fabrics in it. Typical reinforcements can be inorganic materials such as fiberglass or carbon fiber; natural organic fibers such as silk, cotton, wool or the like or synthetic organic fibers such as urethane fibers, nylon filaments, nylon fabrics, aramid filaments and fabrics, and the like. This reinforcement can be laminated into the foam, incorporated into the foam or otherwise compounded into the foam as is known by those skilled in the art.
In the embodiment shown in FIGS. 1 and 2, the internal foam core is preshaped to fit tightly within the outer wall of the impact absorber.
This intimate fit may be accomplished in other ways as well. For one, the core can be foamed in place within the wall structure using injectable flexible foam forming materials known in the art. With the preferred urethane foams, a typical foaming mixture can include a polyether polyol, a diisocyanate such as toluene diisocyanate, water, and amine and organotin catalysts. This mixture generally contains polymeric fillers and flexibilizers (plasticizers) as well. The added water reacts with the isocyanates to produce an amine plus carbon dioxide gas which foams the liquid. Other foaming agents such as gases including carbon dioxide, nitrogen, air or the like as well as low boiling liquids, (commonly low-boiling fluorocarbons and the like) can also be added. By controlling the amount of foaming material added and the cure conditions, the core so formed can, if desired, prestress the outer wall as is preferred. The in situ cores can be closed-cell foams, open-celled foams or reticulated foams as desired.
In a hybrid form of construction, the foam core can be a composite of a preshaped foam body which does not completely fill the cavity created by the outer wall and an added foam-in-place layer between the wall and the preshaped body. This form of fabrication has the advantage that the desired intimate fit is achieved with a minimum of preshaping and fitting while at the same time the preshaped core provides a measure of dimensional stabilty and integrity to the composite during fabrication.
The third component of the impact absorbers of this invention is an adhesive for affixing the foam core to the wall. This adhesive is most conveniently an activated adhesive such as a light activated adhesive, UV activated adhesive or heat activated adhesive so as to permit the parts to be fitted together and then bonded. A typical heat-activated adhesive is the Royal Adhesive DC5 11324 material sold by Uniroyal. This adhesive is a two part poly(urethane)/isocyanate adhesive which has the added advantage of being water-based. When applied to the foam and/or wall it dries to a non-tacky surface which permits easy assembly. This material heat-activates at 300-325° F. to form a tough adherent bond. Other useful adhesives can include epoxy adhesives, contact cement type poly(urethane) adhesives such as the Uniroyal “Silaprenes”, the 3M “Scothgrip” adhesives and the isoprene contact cements. In general, one can employ as adhesive any material which will bond the foam to the outer wall with a strength which will not be exceeded by the forces of impact applied to the impact absorber or by the forces applied by the pressure applied to the impact absorber.
In the fabrication methods in which a liquid solution of prepolymer is applied to the core to create the outer layer or in which the core is foamed in place, it is often the case that the required intimate bond between the core and the outer wall is formed directly without the need for added adhesive.
The outer wall portions of the impact absorber are joined together such as by the use of adhesive or by heat sealing or the like to give a fluid impermeable wall to which the inner core is bonded. After the fusing together of the wall components, the impact absorber can be trimmed and, if desired, further shaped to conform to the environment of use.
The core of the present impact absorbers contain a fluid. Gases and in particular air are very suitable fluids. Liquids and gells could be used as well, if desired.
Turning to FIGS. 3 and 4, the advantages of the impact absorber of this invention are graphically illustrated. In each of these figures a shoe 30 is shown together with foot 31 impacting downward into a heel pad shown as 32 (in FIG. 3 —not according to the invention) and as 10 (in FIG. 4 —in accord with this invention). In the case of heel pad 32 , the downward pressure of the heel causes the center of the pad 34 to be severely depressed while permitting the edges 35 and 36 to balloon up. This can be uncomfortable and unstable. With pad 10 the center 33 depresses somewhat but there is minimal ballooning.
Turning now to FIG. 5, a variation of the core 11 is shown. This core (core 50 ) is fabricated from a plurality of foams of differing properties, for example density. As shown, the core includes a series of plugs. 51 A, 51 B, etc of firm density foam inserted into the body of core 11 . This can result in a light weight core having the firmness of the plugs. This is merely a representative configuration and one could as well have one entire section of the core with one density foam and another section with another density. One could also vary the core based on other properties, such as the ability of a region of the foam to take a set or the like. The various core sections are adhered to the outer wall of the impact absorber as is shown in FIGS. 1 and 2. One could form a core of this type by placing preshaped pieces of one foam in the cavity and then foaming in place the other material, if desired.
The plastic wall of the impact absorber can have structural properties and contribute to the rigidity and shock absorbing properties of the device. FIGS. 6, 7 and 8 illustrate an embodiment 60 of the impact absorber which includes a depression or “column” 61 in its structure so as to provide additional wall surface and structure in that region of the absorber. In this embodiment as shown in FIG. 8, the valve 16 is illustrated being laminated into the composite as the top 12 is joined to the bottom 14 .
FIG. 9 illustrates other variations which may be employed without departing from the spirit of this invention. FIG. 9 shows impact absorber 80 . The foam core of absorber 80 is fabricated from several different foams including foam section 81 , section 82 , section 83 and section 84 . These sections are all adhered to the wall 12 / 14 . Valve 16 is again provided to permit the pressure of the core to be altered and controlled. The various core sections can be adhered to one another, if desired. If they are adhered to one another, it must be borne in mind that the glue layers or the like between the various sections can serve as barriers for the transport of fluid between the various sections. If such fluid communication is desired, gaps must be left in the glue layers or glues which are fluid-permeable must be used.
Absorber 80 includes several other features which can be incorporated into the present absorbers. An exterior pad 85 is provided. This can provide additional shock absorbancy. A top layer 86 is also present. This can be a cosmetic over layer or can be provided as a replaceable hygienic layer.
In the absorbers shown in FIGS. 1, 6 and 9 , the means for adjusting the pressure (valve 16 ) has been in communication with the foam core itself and has relied upon the open-cell foam structure of the core to distribute the applied pressure throughout the core and thus provide a uniform level of support throughout the absorber. While this structure is very suitable, one can also employ closed-cell foams, if desired. FIGS. 10 and and FIGS. 12 and 13 respectively illustrate two representative configurations for a closed-cell foam core. In the configuration shown in FIGS. 10 and 11, the core 87 contains an aperture 88 into which the pressure adjusting valve 16 can fit. This aperture 88 communicates with a network of channels 89 spaced throughout the core so as to transmit and distribute the pressure applied to aperture 88 . In this embodiment, the network of channels is contained by and enclosed by the closed-cell foam core. This means that the core itself can contribute to the containment of the pressure applied to the channels. This offers the advantage that localized stress on the outer wall is avoided or minimized and possible failures due to rupture at localized stress points are minimized.
The configuration shown in FIGS. 12 and 13 is substantially the same as that shown in FIGS. 10 and 11 with the exception that aperture 97 communicates with a network of passages 98 which are not fully contained within the core. This configuration does not offer the localized stress relief of the configuration of FIGS. 10 and 11 but would be less expensive and simpler to produce.
Turning to FIG. 14 an additional embodiment of the impact absorber is shown as foot pad 90 housed within the sole portion of shoe 95 . Foot pad 90 includes the foam core 11 and adherent outer wall 12 / 14 described herein. Pad 90 is equipped with a built in pump to alter the pressure within its core. This pump includes a one way check valve 16 which admits air into pump cavity 91 . Pump cavity 91 is compressed and released to give a region of low pressure so that air can enter through valve 16 . When the cavity 91 is depressed again, this forces the newly admitted air through passage 92 into the core 11 , thus increasing its pressure. This process is repeated until the proper pressure is attained. Shoe 95 also includes a collar 93 . This can be formed with the same structure as pad 90 with an internal core adhered to the walls. Such a collar would be very effective at absorbing the shock which would occur as the wearer's foot comes up in the shoe and impacts it or would be effective as a protection to the wearer's ankle and achilles tendon region.
FIG. 15 illustrates that the present invention finds application in many areas beyond athletic equipment. It illustrates an automotive dashboard structure 101 having an impact pad 100 on its face as well as phantom steering wheel 102 . Impact pad 101 includes core 11 , wall 12 / 14 and valve 16 . Such a pad can provide efficient dashboard impact protection for the occupants of the automobile in the event of a crash.
FIGS. 16 and 17 illustrate in two views a ventilated footpad 110 for use in shoes. Pad 110 has a complex shape which requires numerous compound curves. In its application as a shoe footpad, pad 110 will be subjected to a wide variation in impacts depending upon the weight of the runner using it and the runner's lightness of footstrike. It is of substantial advantage to adjust the pressure within the pad with valve 16 to accommodate these variations.
FIG. 18 illustrates another embodiment of the present invention, an underpad 180 for use in conjunction with contact sports shoulder pads. Underpad 180 has a structure which includes numerous compound curves and a plurality of “Swiss-cheese” holes through its structure. The compound curve-forming ability and the plurality of holes permit the pad to conform to and bend over the wearer's shoulder with comfort and breathability. It is a special advantage that the present invention makes these complex curves possible and provides superior shock and impact absorption in such settings.
The effectiveness of the present invention can be demonstrated by comparative tests. A series of impact tests were run on a standard state-of-the-art basketball shoe. The same tests were then performed on the same model shoe which had been modified by replacing a portion of its sole structure (the heel pad region) with an impact absorber of this invention. The impact absorber was fabricated from 35 mil flexible poly(urethane). The core was about ½ inch thick open-cell poly(urethane) foam of 5 lbs per cubic foot density. The foam core slightly prestressed the outer wall by being somewhat oversized and was adhered to the walls using a heat activated water-based urethane adhesive. Tests were run with the core sealed at atmospheric pressure and with the core pressurized to 5 and 10 psig. FIGS. 19 and 20 present the results of these tests. In each figure line A is the results observed with the prior art shoe. It can be seen that for a given application of energy to the shoe, i.e. a given impact, the shoe transmits a certain peak force and a certain acceleration, (in G's) to the wearer. Lines B show the results achieved when the atmospheric bladder is used. They show that the force and acceleration transmitted to the wearer is significantly reduced. Importantly, this reduction occurs over the entire range of applied energies. Thus the effectiveness of the present absorbers is substantially universal and will be observed with hard impacts such as may result with heavy athletes and also with lighter impacts such as may result with lighter weight athletes, etc.
Lines C show that even better shock absorbancy is achieved when a positive pressure is applied to the bladders. Similar results were obtained with the 5 and 10 pound pressures which suggest that in practical terms these pressures may be quite adequate. On the basis of these tests, it is believed that pressures in the range of 0 to about 20 psig are preferred.
The present invention has been described herein in detail with respect to a number of preferred embodiments and configurations. It will be appreciated, however, that modifications and changes to various aspects of these embodiments may be made while still coming with in the spirit and scope of this invention which is as defined by the following claims. | An improved composite for absorbing and dispersing impacting forces is disclosed. The composite includes a flexible plastic enclosure defining an internal cavity. The flexible enclosure is generally impermeable to air and capable of having its internal pressure changed. The composite further includes a foam core filling the cavity and retained within the cavity and adhered on substantially all of its external surface to the internal surface of the cavity. The cavity can be pressurized for higher impact absorbance. Methods for fabricating the composites are disclosed, as well. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority under 35 USC §119 to Japanese Patent Application Nos. 2008-090535 and 2008-329893, filed on Mar. 31 and Dec. 25, both 2008, the entire contents of which are herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an image forming apparatus and a duplicator, such as a copier, a fax, a printer, etc., and in particular, to a sheet feed tray capable of accurately holding a leading end of the topmost surface of a stack bundle of envelop like recording or printing mediums at its leading end in a sheet feeding direction at a prescribed position of a separation or conveyance mechanism while providing fine quality of constant conveyance.
[0004] 2. Discussion of the Background Art
[0005] Different from a case of a plain sheet, when plural envelope like printing mediums, such as a medicine envelop, a mailing envelope, etc., are stacked in a bundle state, the stacking height varies. For example, when plural envelopes each including a glue longitudinal margin at its widthwise center (e.g. a general envelop) are stacked in the bundle state, the center rises. When side corner of the envelope are accordion folded (e.g. a medicine envelope) to increase an inclusion amount, the thickness of each of the sides becomes twice larger than that of its center, so that a center of the envelope becomes extraordinary thin in comparison with the envelope sides when stacked in the bundle state. When a stacked bundle is depressed to decrease the thickness and accordingly thickness variation as well as the volume thereof, a performance of separating the envelopes deteriorates.
[0006] The Japanese Registered Patent No. 3,542,689 attempts such that a stack use bottom plate is longitudinally divided into plural pieces to be separately pushed up by springs, respectively, so that the topmost surface of a bundle of medicine envelopes pressure contacts a conveyance roller at the leading end in the sheet feeding direction. In such a medicine envelope feeder, to separate and convey the envelopes from the bundle one by one, the bundle needs to uniformly pressure contact the conveyance roller in the axial direction of the conveyance roller. However, in such a separate bottom lift up system, when a spring coefficient is different from others and the envelope bundle decreases, a height of each of the bottom plates gradually becomes different from the other. As a result, a pressure contact force of the envelope stack against the conveyance roller made by bottom plates becomes uneven, so that qualities of separation and conveyance of the stacked envelope deteriorate.
[0007] Further, due to the above-mentioned difficulty, the separate bottom lift up system can not employ a system widely used in a sheet feeding device of an electro-photographic image forming apparatus, in which a leading end of the topmost surface of a sheet bundle is held at a prescribed height and is separated and conveyed by a pick up roller and a sheet feed roller. Specifically, when plural sheet feeding cassettes each having the spring system bottom plate separation construction are piled up, and a stack height detection device is arranged in the vicinity of the pick up roller arranged almost at the widthwise center, the stack height of medicine envelopes becomes lower at the center than its both side ends. As a result, the both side ends contact the bottom plate of the sheet-feeding tray arranged above even the stack height detection device recognizes the height as being appropriate. Specifically, the envelope bundle sometimes causes a problem of separation and conveyance, such as deformation of the bottom plate, breakage of a lifting device, etc., in the worst case.
SUMMARY OF THE INVENTION
[0008] Accordingly, an object of the present invention is to improve such background arts technologies and provides a new and novel sheet-feeding tray. Such an new and novel sheet feeding tray includes a frame member, and freely upwardly swingable plural bottom plates arranged on the frame member side by side perpendicular to a sheet feeding direction. The bottom plates cooperatively support a stack of envelope recording mediums. A lifting device having plural curvature sections is provided. The plural curvature sections are respectively arranged below the bottom plates to scuff and lift the lower surface of the plural bottom plates at a section downstream of the sheet feeding direction.
[0009] The plural curvature sections each include a different outline in accordance with a difference of a decreasing amount of a thickness of the stack during sheet feeding. The different outlines enable the topmost surface of the stack to be almost horizontal.
[0010] In another embodiment, each of plural bottom plates includes one of a concave and convex portion and a friction-decreasing member on the recording medium stacking surface extending in the sheet feeding direction.
[0011] In another embodiment, the lifting device includes one of a concave and convex portion and a friction decreasing member on the surface of the curvature section scuffing the bottom plates.
[0012] In yet another embodiment, the width of the most downstream end in the sheet feed direction of each of the plural bottom plates is different from that at a portion scuffing the bottom plate.
[0013] In yet another embodiment, the swinging center of one of the at least two bottom plates is different from the other.
[0014] In yet an other embodiment, each of the plural bottom plates includes one of a concave and convex section or a hole engageable with the lifting member at the upstream end in the sheet feed direction.
[0015] In yet another embodiment, the lifting member is formed from a single member.
[0016] In yet another embodiment, the lifting member includes at least two cams and a rotational shaft fitting into the at least two cams, each of said at least two cams including a fitted position.
ADVANTAGE
[0017] According to one embodiment of the present invention, even if a stacking height, and accordingly, a number of large envelope like recording mediums decreases, the height of the topmost surface of the envelope like recording mediums can be constant at its leading section enabling stable separation and conveyance. As a result, a freedom of arrangement of a height detection sensor can be increased while avoiding damage of a lifting device and deformation of a bottom plate.
BRIEF DESCRIPTION OF DRAWINGS
[0018] A more complete appreciation of the present invention and many of the attendant advantages thereof 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, wherein:
[0019] FIG. 1 schematically illustrates a construction of an exemplary image forming apparatus;
[0020] FIG. 2 illustrates an exemplary sheet feed tray according to one embodiment of the present invention;
[0021] FIG. 3 is conceptual chart illustrating an exemplary bottom plate lifting mechanism;
[0022] FIG. 4A illustrates an exemplary condition of a bottom plate when a bottom plate lifting operation starts;
[0023] FIG. 4B illustrates an exemplary condition of the bottom plate when sheet feeding starts;
[0024] FIG. 4C illustrates an exemplary condition of the bottom plate when a recording medium is absent;
[0025] FIG. 5 is a chart illustrating an exemplary sequence of bottom plate lifting;
[0026] FIG. 6 is a chart illustrating an exemplary variation of a stacking height of envelope like recording mediums in a widthwise direction appearing when stacked;
[0027] FIG. 7 is a side elevation view illustrating an exemplary stacking condition at a section where a lot of envelope like recording mediums overlap;
[0028] FIG. 8 is a side elevation view illustrating an exemplary stacking condition at a section where a few envelope like recording mediums overlap;
[0029] FIG. 9A is a chart illustrating an outer circumferential outline of a disc cam arranged at a thinner portion of the stack;
[0030] FIG. 9B is a chart illustrating an outer circumferential outline of a disc cam arranged at a thicker portion of the stack;
[0031] FIG. 10 is a graph illustrating a relation between a swinging angle and a height of a leading end of the bottom plate which uniquely changes in accordance with a difference of an outline of an outer circumference of a cam contacting a bottom plate when recording mediums are not stacked and a central bottom plate piece is higher than others;
[0032] FIG. 11A is a chart illustrating a condition where a bottom plate piece start rising as a cam shaft rotates from when a cam shaft rotation angle is zero and the bottom plate piece supporting a thicker side of a stack of recording mediums is positioned lowest;
[0033] FIG. 11B is a chart illustrating a condition where the shaft rotation angle is maximum while the bottom plate piece supporting a thicker side of the stack of recording mediums is positioned highest;
[0034] FIG. 11C is a chart illustrating a condition where the camshaft rotation angle is zero and the bottom plate piece supporting a thinner side of the recording medium is positioned lowest;
[0035] FIG. 11D is a chart illustrating a condition where the cam shaft rotation angle is maximum and the bottom plate supporting the thinner side of the stack of recording mediums is positioned highest;
[0036] FIG. 12 is a chart illustrating a modification of the cam arranged on the thinner side of the stack of recording mediums capable of aligning the height of all of the bottom plate pieces when the recording medium are not stacked;
[0037] FIG. 13 is a graph illustrating a condition where a relation between a change of a swinging angle and a height of a leading end of the bottom plate uniquely changes in accordance with a difference of an outline of an outer circumference section of a cam contacting a bottom plate when the height of the bottom plate pieces are aligned and recording mediums are not stacked;
[0038] FIG. 14A is a chart illustrating a condition where a bottom plate piece start rising as a cam shaft rotates from when a cam shaft rotation angle is zero and a bottom plate piece supporting a thicker side of a stack of recording mediums is positioned lowest;
[0039] FIG. 14B illustrates an exemplary condition of the bottom plate when sheet feeding starts;
[0040] FIG. 14C is a chart illustrating a condition where the cam shaft rotation angle is maximum while the bottom plate piece supporting a thicker side of the stack of recording mediums is positioned highest;
[0041] FIG. 14D is a chart illustrating a condition where the camshaft rotation angle is zero and the bottom plate piece supporting the thinner side of the stack of recording mediums is positioned lowest;
[0042] FIG. 14E illustrates an exemplary condition of the bottom plate when sheet feeding starts;
[0043] FIG. 14F is a chart illustrating a condition where the cam shaft rotation angle is maximum and the bottom plate piece supporting the thinner side of the stack of recording mediums is positioned highest;
[0044] FIG. 15 is a perspective view illustrating a modification of a combination of bottom plate separated pieces;
[0045] FIG. 16 is a chart illustrating an exemplary cam member including a cam-scuffing surface having convex and concave portions arranged in parallel to a sheet feeding direction;
[0046] FIG. 17 is a perspective view illustrating another modification of a combination of separated bottom plate pieces;
[0047] FIG. 18 is a perspective view illustrating yet another modification of a combination of separated bottom plate pieces;
[0048] FIG. 19 is a chart illustrating an exemplary bottom plate piece swingably attached to a tray body having a base end side shaped to fit into either a concave piece or a convex hook formed on the tray body;
[0049] FIG. 20 is a perspective view illustrating an exemplary an arm like curvature piece integrally formed on a rotation shaft of the bottom plate-lifting device for lifting the bottom plate by scuffing the lower surface thereof;
[0050] FIG. 21 is a perspective view illustrating an exemplary can having plural fitting positions around the cam shaft circumferential direction; and
[0051] FIG. 22 is a perspective view illustrating another cam having plural fitting positions around the camshaft circumferential direction.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0052] Referring now to the drawing, wherein like reference numerals designate identical or corresponding parts throughout several views, In particular in FIG. 1 , an outline of an image forming apparatus of a laser printer including a sheet feed tray according to one embodiment of the present invention is described. As shown, in an image formation section including a photoconductive member, an exposure device, and a developing device or the like, an image formed by an electro-photographic system is primarily transferred onto an intermediate transfer belt 20 . At a second transfer section, the image is transferred by a second transfer roller 22 pressure contacting the intermediate transfer belt 20 onto a recording medium. When detected by a detection device, not shown, at a sheet feed start position, a recording medium is launched by a sheet feeding mechanism from one of a sheet cassette 24 and a manual sheet feed tray 26 to the second transfer section via a pair of registration rollers 28 . After having been subjected to a transfer process, the image is fixed by a fixing device 30 and is ejected onto a sheet ejection tray 34 by a sheet ejection roller 32 when a simplex image is formed. Whereas when a duplex image is formed, the recording medium having the fixed image on its one side is fed again via a sheet inversion device 36 and is led to the second transfer section. Then, the other side is subjected to image transfer and fixing process is ejected onto the sheet ejection tray 34 .
[0053] Now, the sheet feeding cassette 24 having an envelope like recording medium use sheet feed tray is described according to one embodiment of the present invention with reference to FIG. 2 . The sheet feeding cassette 24 includes a frame member like tray body 4 having a handle section 2 , a pair of side fences 6 a and 6 b slidably supported on the tray body 4 , and an end fence 8 freely slidably supported by the tray body 4 at both front and the rear sides in the sheet feeding direction. Also included is a swingable bottom plate 10 supported by a pin on the tray body 4 at its base end to mount a stack of recording mediums. Further included is a cam structure arranged below the bottom plate 10 for pressurizing a leading end of a stack of recording mediums against a pick up roller, not shown.
[0054] The bottom plate 10 is divided into three bottom plate pieces 10 A to 10 C in a sheet cassette widthwise direction. Each of these bottom plate pieces 10 A to 10 C is commonly attached to the tray body 4 by a supporting pin 11 as a swingable center at their base end, so that each of front sides thereof is upwardly movable around the supporting pin. A lifting device for upwardly moving the bottom plate includes a camshaft 12 and plural disc cams 13 a to 13 C secured and penetrated by the camshaft 12 . The disk cams 13 A to 13 C each includes a prescribed shape corresponding to each of the bottom plate pieces 10 A to 10 C, wherein two of those ( 13 A and 13 C) are common. When the sheet cassette 24 is inserted into the apparatus body, the camshaft 12 engages with a coupling of a gear-attached motor 9 as shown in FIG. 3 so that the bottom plate can be lifted. When the disc cam 13 rotates as the camshaft 12 rotates, the bottom plate pieces change their rotation angles along the lines of the outer circumferential sections of respective disc cams (e.g. prescribed outlines) contacting a bottom plate.
[0055] Now, a lifting operation of the bottom plate pieces accompanying the rotation of the disc cam is described with reference to FIG. 4 , wherein a bottom plate is lifter and detected by a detection device. When the bottom plate is located at the lowest position as shown in FIG. 4A and a power is supplied and the detection device detects presence of the sheet cassette (the tray) in step S 1 , the gear-attached motor 9 starts rotating and drives the disc cam 13 via the camshaft 12 and swings the bottom plate 10 , so that the recording medium is lifted up. When the bottom plate swings and the topmost surface of the stack of the recording mediums reaches a prescribed position and the effect is detected by a first filler 25 constituting a upper surface detection device in step S 2 and a second filler 27 constituting a recording medium detection device in step S 3 , the driving device stops driving as shown in FIG. 4B . Thus, a prescribed pressure is always applied to the pick up roller 23 at the stopping position. When the pick up roller 23 rotates, the sheet-feeding roller conveys the recording medium to the pair of registration rollers 28 . As mentioned, FIG. 4B illustrates a condition where the bottom plate 10 is lifted and the recording medium 21 is ready for sheet feeding. Herein after, an operation starting from when the cam shaft 12 rotates from the bottom plate lowermost position of FIG. 4A to when it stops in a condition as shown in FIG. 4B is called a sheet lifting operation.
[0056] When the recording medium is conveyed to the image formation section, and the upper surface of the stack lowers, the driving device operates and lifts the bottom plate until the upper surface can be detected, because the upper surface detection device detects nothing. As far as the recording mediums remain on the bottom plate, lifting and non-lifting of the bottom plate are repeated. As shown in FIG. 4C , when no recording medium exists on the bottom plate, the second filler 27 slips into a detection hole 29 formed on the bottom plate and positions therebelow, and detects that the recording medium has gone from the bottom plate. Such an effect is then displayed on an operation section, not shown. When an operator attempts to withdraw the sheet cassette from the apparatus body, a coupling between the cam shaft 12 and the driving device disengages with the camshaft 12 of the sheet cassette, and the bottom plate returns by its gravity to the lowest position, so that the sheet cassette can be detached.
[0057] Now, an exemplary outline shape of the outer circumferential scuffing section of the disc cam having a function of lifting the bottom plate piece is described. Herein below it is premised that thickness variation of envelope like recording mediums is symmetrical in the widthwise direction when stacked. At that moment, as recognized from FIG. 6 , a thickness of stack varies in the widthwise direction, and accordingly, each of the leading ends of the bottom plate pieces 10 A and 10 C supporting the recording medium take lower positions (Hc=Ha) as shown in FIG. 7 , while the central bottom plate piece 10 B takes a higher position (Hb) (also see FIG. 8 ). Legend Hsf represents an upper surface of the recording medium when sheet feed starts.
[0058] The image forming apparatus controls the camshaft 12 to rotate so that the upper surface comes to the height Hsf. Herein below, it is premised that the camshaft and the bottom plate-swinging shaft are arranged on the same level and a thickness of the bottom plate is neglected.
[0059] The outline shape of the disc cams contacting and lifting the bottom plate pieces meets the following condition at the outer circumferential scuffing sections when the rotation angle of the camshaft theta (θ) is zero, i.e., the bottom plate exists at the lowest position;
Hb 0 (Height of the bottom plate piece 10 B)>Ha 0 (Height of the bottom plate pieces 10 a, 10 c )
[0061] When the rotation angle of the camshaft theta is maximum (θ=θmax), all of the heights of the bottom plate pieces 10 a to 10 c amounts to Hsf. As the rotation angle of the camshaft changes from zero to maximum, the cam outer circumference needs to increase a distance between the scuffing portion and the camshaft. For example, the change shows a clothoid curve gradually increasing a distance. For example, the outline shape is shown in FIG. 9 meeting the following formulas, wherein “A” represents a rotation angle of curvature radius, alpha 1 and 2 represent increase rates of the curvature radius:
[0000] Disc cam 13 b: R 1=alpha1 ×A+Hb 0
[0000] Disc cam 13 a: R 2=alpha2 ×A+Ha 0
[0062] The increase rates of the curvature radius correspond to changes of a thickness at the center and both sides from when the stack of envelope like recording mediums is maximum to when the last recording medium remains. Such increase rates are previously experienced as follows:
Alpha 1:Alpha 2=1:2
[0064] When respective disc cams including an outline of FIG. 9 are used, the leading end height of the bottom plate piece 10 b is higher than that of the leading end height of both sides of the bottom plate pieces 10 a and 10 c when the envelope like recording mediums are not stacked. A relation between the camshaft rotation angle theta (θ) and the bottom plate height established from when the stack of the envelope like recording mediums is lifted to when the topmost recording medium bundle contacts and fed by the pickup roller is illustrated in FIG. 10 . Exemplary conditions of respective bottom plate pieces when the camshaft rotation angle is both zero and maximum are illustrated in FIG. 11 .
[0065] Depending on a cam shape, a contact position on the bottom plate largely deviates as the cam rotates, and the height of the bottom plate cannot correspond to the outline of the cam. In such a situation, by providing a convex shape to the can contact section on the bottom plate, deviation of the contact position is suppressed and the change in the height of the bottom plate can correspond to the outline of the cam.
[0066] When no recording medium exists and the heights of the bottom plate pieces are not the same with each other, the recording mediums are hardly set correctly. Then, the height should be aligned by shaping the cam for central bottom plate piece use by cutting away the upper side thereof as shown in FIG. 12 . A relation between the camshaft rotation angle theta (θ) and the bottom plate height established when the stack of the envelope like recording mediums is lifted and the topmost recording medium contacts and fed by the pickup roller while using the above-mentioned central bottom plate piece use cam is illustrated in FIG. 13 . Exemplary conditions of respective bottom plate pieces when the camshaft rotation angle is zero, and the sheet feed start time angle theta 1 (θ 1 ), as well as the maximum angle (θmax) are illustrated in FIG. 14 .
[0067] As mentioned heretofore, height variation of the stack of the envelope recording mediums can be corrected and the topmost surface of the recording mediums in the sheet feed front side can be held flattened. With provision of plural disc cams having a different outer circumferential scuffing outline, the relation between the bottom plate angle and the bottom plate height shown in FIG. 2 can be appropriately changed in accordance with a type of the envelope like recording medium. In this example, the disc cam and the camshaft are used as a bottom plate-lifting device. However, the other lifting member can be employed as far as it includes an outline corresponding to a change in a thickness of an envelope like printing mediums. For example, a curvature outline can be formed on an arm piece integral with the rotation shaft as mentioned later in detail with reference to FIG. 20 to correspond to the change of the thickness of the envelope like printing mediums.
[0068] Now, a modification of division bottom plate piece combination is described with reference to FIG. 15 . To reduce conflicting force between stacked recording mediums and a bottom plate, convex beads 14 are provided on the bottom plates 10 a to 10 c. However, instead of the beads, confliction reduction members can be attached. Similarly, convex beads can be provided on the rear side of the bottom plates 10 a to 10 c, i.e., on the side of the bottom plate-lifting device (i.e., cam) to reduce lifting between the bottom plate and the bottom plate elevation device. Specifically, by arranging the convex beads 15 on the outer circumferential scuffing surface of the cam 13 , scuffing confliction caused on the bottom plate is reduced. Instead of the bead, a miler (a name of commodity) sheet, a Teflon™ sheet and the like can be attached.
[0069] Now, yet another modification of the division bottom plate piece combination is described with reference to FIG. 17 . The central bottom plate piece 10 b ′ becomes sharp at a tip more than the base end. In accordance with the shape of the central bottom plate piece 10 b ′, the side end use bottom plate pieces 10 a ′ and 10 c ′ become wider toward their tips. With such a shape, when a curled radius of a stack of envelope like recording mediums is small, a close contact performance of the central bottom plate piece 10 b ′ relation to the central region of the stack can be improved.
[0070] Another modification of the division bottom plate piece combination of FIG. 18 shows a construction in that a rotational center of one of bottom plate pieces is differentiated from the above-mentioned modifications. In contrast to the drawing, the central bottom plate piece can be shorter. Thus, by changing the rotational center of the bottom plate piece different from that rotating around the same axis, a relation between a rotation angle and a height can be changed even if the same disc cams are used as mentioned earlier.
[0071] FIG. 19 illustrates an attempt for simplifying an assembling operation for assembling a bottom plate and a sheet feed tray. Specifically, one of a convex or concave section and a hole is formed on a bottom plate piece at its base end to fit into a concave piece 16 or a convex hook 17 formed on a tray body. Thus, the fitting section serves as a rotation center of the bottom plate.
[0072] FIG. 20 illustrates an example, in which plural arm like curvature pieces 19 a to 19 c are provided integral with a rotation shaft 18 , which is included in a bottom plate lifting device 18 , to lift the bottom plate while scuffing the lower surface of the bottom plate. The plural arm like curvature pieces 19 a to 19 c are made of the same material such as iron, brass, aluminum, etc., and resin, ABS, POM, and PC resin. A curved outlines of the arm like curvature pieces correspond to changes in a thickness of each of corresponding positions of envelope like printing mediums.
[0073] The outline shape of the outer circumferential scuffing section of the cam member for lifting the bottom plate is determined to uniquely change a bottom plate leading end as the bottom plate changes its rotation angle, and is thus different in accordance with a type of an envelope like recording medium. However, it is experienced that a process of the outline change is almost the same even when a type of recording medium is different and the thickness of the stack varies. Then, a structure capable of changing a fitting position of a shaft fitting into a cam member in a rotation direction is changed as described with reference to FIG. 21 .
[0074] As shown, a concave and convex section is formed around a shaft hole on a cam member 13 ′ and engages with a pin section attached to the camshaft 127 . After engagement, a securing member, such as an E-letter shaped ring, a stopping ring, etc., prevents a shaft direction movement of the cam member 13 ′.
[0075] Otherwise, a fastening device can reduce a diameter of the hole of the cam member to prevent the shaft direction movement of the cam member 13 ′. As shown in FIG. 22 , a sprain state groove is formed on a shaft inner surface of the cam member” and is engaged with a sprain state groove formed on the surface of the camshaft 12 ″. Similar to the example as described with reference to FIG. 21 , a fixing member such as an E-letter shaped ring, a stopping ring, etc., prevents a shaft direction movement of the cam member 13 ′ after engagement.
[0076] Obviously, numerous additional modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described herein. | A sheet feeding tray includes a frame member, and freely upwardly swingable plural bottom plates arranged on the frame member side by side perpendicular to a sheet feeding direction. The bottom plates cooperatively support a stack of envelope recording mediums. A lifting device having plural curvature sections is provided. The plural curvature sections are respectively arranged below the bottom plates to scuff and lift the lower surface of the plural bottom plates at a section downstream of the sheet feeding direction. The plural curvature sections each include a different outline in accordance with a difference of a decreasing amount of a thickness of the stack during sheet feeding. The different outlines enable the topmost surface of the stack to be almost horizontal. | 1 |
This application is a continuation-in-part of U.S. patent application Ser. No. 10/064,248, filed Jun. 25, 2002 now U.S. Pat. No. 6,484,509 and assigned to the same assignee hereof.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to a method for cooling the combustion chamber and venturi used in a gas turbine engine for reducing nitric oxide emissions and to a structure for improved cooling effectiveness of a venturi throat region. Specifically a method is disclosed for cooling the combustion chamber/venturi to lower nitric oxide (NOx) emissions by introducing preheated cooling air into the premix chamber for use in the combustion process.
2. Description of Related Art
The present invention is used in a dry, low NOx gas turbine engine typically used to drive electrical generators. Each combustor includes an upstream premix fuel/air chamber and a downstream combustion chamber separated by a venturi having a narrow throat constriction that acts as a flame retarder. The invention is concerned with improving the cooling of the combustion chamber which includes the venturi walls while at the same time reducing nitric oxide emissions.
U.S. Pat. No. 4,292,801 describes a gas turbine combustor that includes upstream premix of fuel and air and a downstream combustion chamber.
U.S. Pat. No. 5,117,636 and U.S. Pat. No. 5,285,631 deal with cooling the combustion chamber wall and the venturi walls. The patents state that there is a problem with allowing the cooling air passage to dump into the combustion chamber if the passage exit is too close to the venturi throat. The venturi creates a separation zone downstream of the divergent portion which causes a pressure difference thereby attracting cooling air which can cause combustion instabilities. However, it is also essential that the venturi walls and combustion chamber wall be adequately cooled because of the high temperatures developed in the combustion chamber.
The present invention eliminates the problem discussed in the prior art because the cooling circuit for the venturi has been adjusted such that the cooling air no longer dumps axially aft and downstream of the venturi throat into the combustion zone. In fact, cooling air flows in the opposite direction so that the air used for cooling the combustion chamber and the venturi is forced into the premix chamber upstream of the venturi, improving the efficiency of the overall combustion process while eliminating any type of cooling air recirculation separation zone aft of the venturi as discussed in the U.S. Pat. No. 5,117,636.
Recent government emission regulations have become of great concern to both manufacturers and operators of gas turbine combustors. Of specific concern is nitric oxide (NOx) due to its contribution to air pollution.
It is well known that NOx formation is a function of flame temperature, residence time, and equivalence ratio. In the past, it has been shown that nitric oxide can be reduced by lowering flame temperature, as well as the time that the flame remains at the higher temperature. Nitric Oxide has also been found to be a function of equivalence ratio and fuel to air (f/a) stoichiometry. That is, extremely low f/a ratio is required to lower NOx emissions. Lowering f/a ratios do not come without penalty, primarily the possibility of “blow-out”. “Blow-Out” is a situation when the flame, due to its instability, can no longer be maintained. This situation is common as fuel-air stoichiometry is decreased just above the lean flammability limit. By preheating the premix air, the “blow-out” flame temperature is reduced, thus allowing stable combustion at lower temperatures and consequently lower NOx emissions. Therefore, introducing the preheated air is the ideal situation to drive f/a ratio to an extremely lean limit to reduce NOx, while maintaining a stable flame.
In a dual-stage, dual-mode gas turbine system, the secondary combustor includes a venturi configuration to stabilize the combustion flame. Fuel (natural gas or liquid) and air are premixed in the combustor premix chamber upstream of the venturi and the air/fuel mixture is fired or combusted downstream of the venturi throat. The venturi configuration accelerates the air/fuel flow through the throat and ideally keeps the flame from flashing back into the premix region. The flame holding region beyond the throat in the venturi is necessary for continuous and stable fuel burning. The combustion chamber wall and the venturi walls before and after the narrow throat region are heated by the combustion flame and therefore must be cooled. In the past, this has been accomplished with back side impingement cooling which flows along the back side of the combustion wall and the venturi walls where the cooling air exits and is dumped into combustion chamber downstream of the venturi.
The present invention overcomes the problems provided by this type of air cooling passage by completely eliminating the dumping of the cooling air into the combustion zone downstream of the venturi. The present invention does not permit any airflow of the venturi cooling air into the downstream combustion chamber whatsoever. At the same time the present invention takes the cooling air, which flows through an air passageway along the combustion chamber wall and the venturi walls and becomes preheated and feeds the cooling air upstream of the venturi (converging wall) into the premixing chamber. This in turn improves the overall low emission NOx efficiency.
BRIEF SUMMARY OF THE INVENTION
An improved method for cooling a combustion chamber wall having a flame retarding venturi used in low nitric oxide emission gas turbine engines that includes a gas turbine combustor having a premixing chamber and a secondary combustion chamber and a venturi, a cooling air passageway concentrically surrounding said venturi walls and said combustion chamber wall. A plurality of cooling air inlet openings into said cooling air passageway are disposed near the end of the combustion chamber.
The combustion chamber wall itself is substantially cylindrical and includes the plurality of raised ribs on the outside surface which provide additional surface area for interaction with the flow of cooling air over the combustion cylinder liner. The venturi walls are also united with the combustion chamber and include a pair of convergent/divergent walls intricately formed with the combustion chamber liner that includes a restricted throat portion. The cooling air passes around not only the cylindrical combustion chamber wall but both walls that form the venturi providing cooling air to the entire combustor chamber and venturi. As the cooling air travels upstream toward the throat, its temperature rises.
The cooling air passageway is formed from an additional cylindrical wall separated from the combustion chamber wall that is concentrically mounted about the combustion chamber wall and a pair of conical walls that are concentrically disposed around the venturi walls in a similar configuration to form a complete annular passageway for air to flow around the entire combustion chamber and the entire venturi. The downstream end of the combustion chamber and the inlet opening of the cooling air passageway are separated by a ring barrier so that none of the cooling air in the passageway can flow downstream into the combustion chamber, be introduced downstream of the combustion chamber, or possibly travel into the separated region of the venturi. In fact the cooling air outlet is located upstream of the venturi and the cooling air flows opposite relative to the combustion gas flow, first passing the combustion chamber wall and then the venturi walls. The preheated cooling air is ultimately introduced into the premix chamber, adding to the efficiency of the system and reducing nitric oxide emissions with a stable flame.
The source of the cooling air is the turbine compressor that forces high pressure air around the entire combustor body in a direction that is upstream relative to the combustion process. Air under high pressure is forced around the combustor body and through a plurality of air inlet holes in the cooling air passageway near the downstream end of the combustion chamber, forcing the cooling air to flow along the combustor outer wall toward the venturi, passing the throat of the venturi, passing the leading edge of the venturi wall where there exists an outlet air passageway and a receiving channel that directs air in through another series of inlet holes into the premix chamber upstream of the venturi throat. With this flow pattern, it is impossible for cooling air to interfere with the combustion process taking place in the secondary combustion chamber since there is no exit or aperture interacting with the secondary combustion chamber itself. Also as the cooling air is heated in the passageway as it flows towards the venturi and is introduced into the inlet premix chamber upstream of the venturi, the heated air aides in combustor efficiency to reduce pollutant emissions.
The outer combustor housing includes an annular outer band that receives the cooling air through outlet apertures upstream of the venturi. The air is then directed further upstream through a plurality of inlet air holes leading into the premix chamber allowing the preheated cooling air to flow from the air passageway at the leading venturi wall into the premix area.
The combustion chamber wall includes a plurality of raised rings to increase the efficiency of heat transfer from the combustion wall to the air, giving the wall more surface area for air contact. Although a separate concentric wall is used to form the air cooling passageway around the combustion chamber and the venturi, it is possible in an alternative embodiment that the outer wall of the combustor itself could provide that function.
In an alternate embodiment of the present invention, a venturi is disclosed that includes a throat region and incorporates a cooling passageway having a reduced cross sectional area proximate the throat region to provide improved cooling effectiveness. The venturi also incorporates a plurality of raised ridges spaced at a predetermined distance from the venturi throat region and from adjacent raised ridges along the cooling passageway such that the raised ridges disturb the cooling flow passing through the passageway, and when used in conjunction with the reduced cross sectional area proximate the throat region, provide a more effective heat transfer mechanism at the venturi throat region.
It is an object of the present invention to reduce nitric oxide (NOx) emissions in a gas turbine combustor system while maintaining a stable flame in a desired operating condition while providing air cooling of the combustor chamber and venturi.
It is another object of this invention to provide a low emission combustor system that utilizes a venturi for providing multiple uses of cooling air for the combustor chamber and venturi.
And yet another object of this invention is to lower the “blow-out” flame temperature of the combustor by utilizing preheated air in the premixing process that results from cooling the combustion chamber and venturi.
And yet a further object of this invention is to provide a gas turbine combustion system utilizing a venturi with a cooling passageway that provides improved cooling to a venturi throat region through cooling passageway geometry changes.
In accordance with these and other objects, which will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a side elevational view in cross-section of a gas turbine combustion system that represents the prior art, which shows an air cooling passage that empties into and around the combustion chamber.
FIG. 2 shows a gas turbine combustion system in a perspective view in accordance with the present invention.
FIG. 3 shows a side elevational view in cross-section of a gas turbine combustor system in accordance with the present invention.
FIG. 4 shows a cut away version in cross section of the combustion chamber and venturi and portions of the premix chamber as utilized in the present invention.
FIG. 5 shows a cross-sectional view, partially cut away of the cooling air passageway at the upstream end of the venturi in the annular bellyband chamber for receiving cooling air for introducing the air into the premix chamber.
FIG. 6 is a cut away and enlarged view of the aft end of the combustion chamber wall in cross-section.
FIG. 7 shows a cross section view of an alternate embodiment venturi in a combustion liner in accordance with the present invention.
FIG. 8 shows a cross section view of an alternate embodiment venturi in accordance with the present invention.
FIG. 9 shows a detail cross-section view of the venturi throat region of an alternate embodiment in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, an existing gas turbine combustor well known in the prior art 110 is shown. The combustor 110 includes a venturi 111 , a premixing chamber 112 for premixing air and fuel, a combustor chamber 113 and a combustion cap 115 . As shown in this prior art combustor, cooling air represented by arrows flows under pressure along the external wall of the venturi 111 . The cooling air enters the system through multiple locations along the liner 110 . A portion of the air enters through holes 120 while the remainder runs along the outer shell. The cooling air, which is forced under pressure, with the turbine compressor as the source, enters the system through a plurality of holes 121 . As seen in FIG. 1 the cooling air impinges and cools the convergent/divergent walls 127 of the venturi 111 , which are conically shaped and travel downstream through the cylindrical passage 114 cooling the walls of combustion cylinder chamber 113 . The cooling air exits along the combustion chamber wall through annular discharge opening 125 . This air is then dumped to the downstream combustion process. A portion of the cooling air also enters the premixing zone through holes 126 . The remaining cooling air proceeds to the front end of the liner where it enters through holes 123 and the combustion cap 115 . The portion of the cooling air that does not enter through holes 123 enters and mixes the gas and fuel through area 124 . U.S. Pat. No. 5,117,636 discusses the prior art configuration of the venturi shown in FIG. 1 . Problems are discussed regarding the cooling air exiting adjacent the venturi 111 through passage exit 125 which interferes with the combustion process and mixture based on what the '636 Patent states as a separation zone.
The present invention completely alleviates any of the problems raised in the '636 Patent.
Referring now to FIGS. 2 and 3, the present invention is shown as gas turbine combustor 10 including a venturi 11 .
The venturi 11 includes a cylindrical portion which forms the combustor chamber 13 and unitarily formed venturi walls which converge and diverge in the downstream direction forming an annular or circular restricted throat 11 a . The purpose of the venturi and the restricted throat 11 a is to prevent flash back of the flame from combustion chamber 13 .
Chamber 12 is the premix chamber where air and fuel are mixed and forced under pressure downstream through the venturi throat 11 a into the combustor chamber 13 .
A concentric, partial cylindrical wall 11 b surrounds the venturi 11 including the converging and diverging venturi walls to form an air passageway 14 between the venturi 11 and the concentric wall 11 b that allows the cooling air to pass along the outer surface of the venturi 11 for cooling.
The outside of the combustor 10 is surrounded by a housing (not shown) and contains air under pressure that moves upstream towards the premix zone 12 , the air being received from the compressor of the turbine. This is very high pressure air. The cooling air passageway 14 has air inlet apertures 27 which permit the high pressure air surrounding the combustor to enter through the apertures 27 and to be received in the first portion 45 of passageway 14 that surrounds the venturi 11 . The cooling air passes along the venturi 11 passing the venturi converging and diverging walls and venturi throat 11 a . Preheated cooling air exits through outlet apertures 28 which exit into an annular bellyband chamber 16 that defines a second portion 46 (FIG. 4) of the passageway 14 . The combustor utilizes the cooling air that has been heated and allowed to enter into premix chamber 12 through apertures 29 and 22 . Details are shown in FIGS. 5 and 6. Note that this is heated air that has been used for cooling that is now being introduced in the premix chamber, upstream of the convergent wall of the venturi and upstream of venturi throat 11 a . Using preheated air drives the f/a ratio to a lean limit to reduce NOx while maintaining a stable flame.
Referring now to FIG. 4, the cooling air passageway 14 includes a first portion 45 having a plurality of spacers 14 a that separate venturi 11 from wall 11 b . The bellyband wall 16 defines a radially outer boundary of the second portion 46 of the passageway 14 and provides a substantially annular chamber that allows the outside pressure air and the exiting cooling air to be received into the premix chamber 12 . At the downstream end of the combustion chamber 13 , defined by the annular aft end of venturi 11 , there is disposed an annular air blocking ring 40 which prevents any cooling air from leaking downstream into the combustion chamber. This alleviates any combustion problems caused by the cooling air as delineated in the prior art discussed above.
Referring now to FIG. 5 the air passageway 14 is shown along the venturi section having the convergent and divergent walls and the throat 11 a with cooling air passing through and exiting through apertures 28 that go into the air chamber formed by bellyband wall 16 . Additional air under a higher pressure enters through apertures 32 and forces air including the now heated cooling air in passageway 14 to be forced through apertures 22 and 29 into the premix chamber 12 .
FIG. 6 shows the aft end portion of the combustion chamber 13 and the end of venturi 11 that includes the blocking ring 40 that is annular and disposed and attached in a sealing manner around the entire aft portion of the venturi 11 . The cooling air that enters into passageway 14 cannot escape or be allowed to pass into any portions of the combustion chamber 13 . Note that some air is permitted into the combustor 10 well beyond combustion chamber 13 through apertures 30 to 31 which are disposed around the outside of the combustor 10 and for cooling the aft end of the combustor.
The invention includes the method of improved cooling of a combustion chamber and venturi which allows the air used for cooling to increase the efficiency of the combustion process itself to reduce NOx emissions. With regard to the air flow, the cooling air enters the venturi outer passageway 14 through multiple apertures 27 . A predetermined amount of air is directed into the passageway 14 by element 17 . The cooling air is forced upstream by blocking ring 40 which expands to contact the combustor 10 under thermal loading conditions. The cooling air travels upstream through the convergent/divergent sections of the first portion 45 of passageway 14 where it exits into the second portion 46 of passageway 14 through apertures 28 in the venturi 11 and the combustor 10 . The cooling air then fills a chamber created by a full ring bellyband 16 . Due to the pressure drop and increase in temperature that has occurred throughout the cooling path, supply air which is at an increased pressure is introduced into the bellyband chamber 16 through multiple holes 32 . See FIGS. 4 and 5. The cooling air passes around multiple elements 18 which are located throughout the bellyband chamber 16 for support of the bellyband under pressure. The cooling air is then introduced to the premix chamber through holes 22 and slots 29 in the combustor 10 . Undesired leakage does not occur between the cooling passageway 14 and the premixing chamber 12 because of the forward support 19 which is fixed to the combustor 10 and venturi 11 . The remainder of the cooling air not introduced to passageway 14 through apertures 27 passes over the element 17 and travels upstream to be introduced into the combustor 10 or cap 15 . This air is introduced through multiple locations forward of the bellyband cavity 16 .
It is through this process, rerouting air that was used for cooling and supplying it for combustion, that lowers the fuel to air ratio such that NOx is reduced without creating an unstable flame.
Referring now to FIGS. 7-9, an alternate embodiment of the present invention is shown in detail. In this alternate embodiment, improvements have been made in the venturi throat region to enhance cooling effectiveness. As with the preferred embodiment and shown in FIG. 7 , a venturi 60 is positioned within a liner 61 having a first generally annular wall 62 . Liner 61 contains a premix chamber 63 for mixing fuel and air and a combustion chamber 64 proximate venturi 60 such that premixing chamber 63 is in fluid communication with combustion chamber 64 . First generally annular wall 62 contains at least one first aperture 65 and at least one second aperture 66 , radially outward of premix chamber 63 . It is preferable that both first aperture 65 and second aperture 66 comprise a plurality of first and second apertures spaced circumferentially about wall 62 .
Referring now to FIGS. 8 and 9, venturi 60 includes a second generally annular wall 67 having a first converging wall 68 abutting a first diverging wall 69 at a first plane 70 that is generally perpendicular to first generally annular wall 62 . Venturi 60 further contains a throat portion 11 A at first plane 70 such that throat portion 11 A is positioned between premix chamber 63 and combustion chamber 64 . Second generally annular wall 67 is positioned radially inward from first generally annular wall 62 and has an aft end 71 adjacent to at least one first aperture 65 . Referring to FIG. 7, venturi 60 further includes a third generally annular wall 72 radially outward of second generally annular wall 67 and radially inward of first generally annular wall 62 . Referring to FIG. 9, third generally annular wall 72 contains a second converging wall 73 and a second diverging wall 74 connected at a first region of curvature 75 proximate first plane 70 and having a first radius R1. In order to improve the cooling effectiveness along second generally annular wall 67 at throat region 11 A, the geometry of third generally annular wall 72 proximate first region of curvature 75 changes to restrict the area for cooling flow through first portion 45 of passageway 14 proximate throat 11 A. Second converging wall 73 contains a first convergent member 73 A and a second convergent member 73 B, and second diverging wall 74 contains a first divergent member 74 A and a second divergent member 74 B, such that second convergent member 73 B and second divergent member 74 B are located adjacent first region of curvature 75 . Furthermore, first divergent member 74 A is oriented at an angle α 1 relative to first plane 70 , second divergent member 74 B is oriented at an angle α 2 relative to first plane 70 , first convergent member 73 A is oriented at an angle α 3 relative to first plane 70 , and second convergent member 73 B is oriented at an angle α 4 relative to first plane 70 . In order to form the restricted flow areas, the respective convergent and divergent members are oriented at angles such that α 2 <α 1 and α 4 <α 3 , thereby forming a first region of reduced cross sectional area A1 between first diverging wall 69 and second divergent member 74 B and a second region of reduced cross sectional area A2 between first converging wall 68 and second convergent member 73 B. In the preferred configuration of this alternate embodiment, angles α 1 and α 3 are at least 40 degrees and angles α 2 and α 4 are equal such that, for optimum heat transfer along throat region 11 A, first reduced cross sectional area A1 is substantially equal to second reduced cross sectional area A2.
Referring back to FIG. 7, venturi 60 contains a passageway 14 for flowing air to cool second generally annular wall 67 . Passageway 14 extends from at least one first aperture 65 to at least one second aperture 66 in liner 61 . Passageway 14 includes a first portion 45 located radially inward from third generally annular wall 72 and radially outward of second generally annular wall 67 as well as a second portion 46 radially outward of first portion 45 where second portion 46 extends from first portion 45 to at least one second aperture 66 . A substantially annular bellyband wall 80 is located radially outward from first generally annular wall 62 thereby defining the radially outer boundary of second portion 46 of passageway 14 . At least one third aperture 81 is located in first generally annular wall 62 and communicates with second portion 46 . It is preferable that at least one third aperture 81 comprises a plurality of third apertures which are spaced circumferentially about first generally annular wall 62 and radially outward of venturi 60 for communicating cooling flow from first portion 45 with second portion 46 . Further characteristics of passageway first portion 45 , which are shown in FIGS. 8 and 9, include at least one first aperture 65 located radially outward of first portion 45 and first portion 45 having a second region of curvature 76 with radius R2 proximate throat region 11 A. In the preferred configuration of this alternate embodiment first radius R1 is smaller than second radius R2 with second radius R2 being at least 0.150 inches.
Referring now to FIG. 9, a plurality of raised ridges 77 and 77 A are located throughout first portion 45 of passageway 14 and fixed along second generally annular wall 67 such that they extend into first portion 45 . Raised ridges are utilized to interrupt the cooling air flowing through first portion 45 causing a turbulent flow, which results in improved heat transfer. In the preferred configuration of the alternate embodiment, raised ridges 77 and 77 A are round in cross section having a diameter D1, typically at least 0.031 inches. Though raised ridges 77 and 77 A can be manufactured integral to second generally annular wall 67 , it is preferred that raised ridges 77 and 77 A are fixed to second generally annular wall by a means such as brazing or welding. This configuration results in an equivalent function to integral ridges, and for raised ridges of circular cross section results in a lower manufacturing cost. Raised ridges 77 are spaced along second generally annular wall 67 at a distance L1 that for the preferred configuration of this alternate embodiment is typically between four and fifteen times diameter D1. Raised ridges 77 A, which are immediately adjacent throat region 11 A, are spaced a distance L2 from throat region 11 A where L2 is typically between five and twenty-five times diameter D1. Distance L2 varies as a function of diameter D1 in order to provide the optimal heat transfer effect. The combination of third generally annular wall 72 geometry, spacing L1 and L2 of raised ridges 77 and 77 A, and the resulting wake region and associated turbulence to the cooling flow from raised ridges 77 and 77 A serve to improve overall heat transfer effectiveness proximate venturi throat region 11 A.
Extending from aft end 71 is a blocking ring 40 that is in sealing contact with first generally annular wall 67 . Blocking ring 40 is utilized to prevent cooling air that is in first portion 45 of passageway 14 from flowing directly into combustion chamber 64 without first flowing through second portion 46 of passageway 14 and into premix chamber 63 .
Through utilizing this venturi structure, not only are emissions reduced by improving overall combustion efficiency through introducing cooling air from passage 14 into the combustion process, but cooling effectiveness within passageway 14 at throat 11 A is improved due to a more efficient passageway geometry proximate first plane 70 .
While the invention is been described and is known as presently the preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment but, on the contrary, it is intended to cover various modifications and equivalent arrangements within the scope of the following claims. | A method for providing cooling air to the venturi and the combustion chamber in a low NOx emission combustor as used in a gas turbine engine that includes the steps of providing an annular air passage surrounding said combustion chamber and venturi where said cooling air under pressure enters the combustion chamber/venturi near the aft portion of the combustion chamber, passing the air along the combustion chamber, past the venturi where the air exits near the front portion of the convergent area of the venturi. The method prevents any channel/passage cooling air from being received into the combustion chamber, and at the same time, introduces the outlet of the cooling air, after the air has passed over the combustion chamber of the venturi and has been heated, back into the premix chamber thereby improving the efficiency of the combustor while reducing and lowering NOx emission in the combustion process. In an alternate embodiment, a venturi is disclosed that incorporates a cooling passageway have a region of reduced area proximate a venturi throat region. The reduced area in conjunction with a plurality of raised ridges, located along the cooling passageway, for disturbing the cooling flow, enhance overall cooling effectiveness and improve venturi throat heat transfer. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a vanity case of the type in which a receptacle member and a cover member are hinged together at respective rear ends and the cover member is maintained in a closed position with respect to the receptacle member by engagement of latch means formed on the front ends of both members.
2. Description of the Prior Art
Various attempts and efforts have hitherto been made in order to facilitate an opening operation of the cover member, and a push piece has been proposed and found effective. For example, U.S. Pat. No. 4,276,893 discloses such a push piece which is slidably arranged in a recess formed in a marginal portion of the receptacle member. The push piece includes an enlarged head to provide an inclined surface which, upon inward movement of the push piece, acts on a nose of the cover and forces the latter upwardly to thereby release the engagement of latch means. U.S. Pat. No. 4,366,829 also discloses a similar push piece having an elastic member for urging it outwardly. In these vanity cases, however, the force acting on the nose is in a direction perpendicular to the inclined surface and therefore includes a force component in a horizontal direction, which component tends to urge the nose toward the inner wall of the recess where one of the latch means is formed. It would be thus understood that a user has to press the push piece with a relatively large force in order to open the cover since the horizontal force component tends to strengthen the engagement between the latch means. This is not desirable in view of the nature of the vanity case.
U.S. Pat. No. 4,387,730, discloses another type of push piece in which one of the latch means is formed on the push piece so that the inward movement of the latter separates its latch from the other, stationary latch to release the engagement. Further inward movement of the push piece causes an inclined surface thereof to force up the cover. An enlarged head for providing the inclined surface renders the entire push piece thick and bulky.
Also, U.S. Pat. No. 4,399,826 teaches an L-shaped push piece which is pivotally secured to the receptacle in such a manner that one end of the push piece acts on the nose to force up the cover when the push piece is rotated. The rotation is caused only by pressing a lower portion remote from the pivot of the other end of the push piece, which requires a somewhat delicate operation.
Further, U.S. Pat. Nos. 4,679,576 and 4,683,899 disclose a push piece having a front wall and an arm integrally formed with the front wall through a thin flexible section which permits the arm to swing relative to the front wall. The arm, upon inward movement of the push piece, acts on the nose to force the cover in upward and forward directions. The recess, however, should have a dimension sufficiently large to permit the sliding movement of the front wall and the swinging motion of the arm.
Thus, all of the prior art, vanity cases are still unsatisfactory with regard to handling ability and/or the size for the push piece, and it is therefore an object of the invention to provide a vanity case having an improved operability with a reduced space for a push piece.
SUMMARY OF THE INVENTION
According to the invention, a vanity case comprises a receptacle member, a cover member hinged with the receptacle member at the rear end thereof, latch means for maintaining the cover member in a closed position with respect to the receptacle member, a push piece and stationary abutment means. The push piece has formed therein a center opening and an arm swingably connected to the rear wall defining the center opening, and is slidably movable along the longitudinal direction of the vanity case. The arm has a portion extending forwardly from the rear wall and adjacent at least one of the receptacle and cover members in the closed position of the cover member. The stationary abutment means is arranged to, upon rearward movement of the push piece, abut against the arm and cause the arm to swing relative to the rear wall with the front portion of the arm moving in the center opening, thereby forcing the receptacle and cover members away from each other.
Other objects, features and advantages of the invention will be apparent from the following detailed description thereof when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinally sectioned view of a vanity case according to an embodiment of the invention;
FIG. 2 is an enlarged perspective view showing a push piece of the vanity case in FIG. 1;
FIG. 3 is an enlarged fragmentary view of the vanity case;
FIG. 4 is a view similar to FIG. 3 showing an operation of the push piece;
FIG. 5 is an enlarged partly sectioned perspective view illustrating a push piece according to another embodiment of the invention;
FIG. 6 is a fragmentary sectional view of a vanity case incorporating the push piece of FIG. 5;
FIG. 7 is a similar view showing an operation of the push piece;
FIG. 8 is a perspective view of a push piece according to another embodiment of the invention;
FIGS. 9 and 10 are fragmentary sectional views of a vanity case having the push piece of FIG. 8;
FIG. 11 is a partly sectioned perspective view of a push piece according to another embodiment of the invention;
FIGS. 12 and 13 are a perspective view and a longitudinally sectioned view, respectively, of a push piece according to another embodiment of the invention, in the form as molded;
FIG. 14 is a perspective view of the push piece of FIGS. 12 and 13 in the form ready for assembly;
FIG. 15 is a fragmentary section of a vanity case incorporating the push piece of FIG. 14;
FIGS. 16 and 17 are views similar to FIG. 15 showing an operation of the push piece;
FIGS. 18 and 19 are views similar to FIGS. 15 and 16, respectively, for illustrating a slightly modified example;
FIG. 20 is a longitudinal section of a vanity case according to another embodiment of the invention;
FIG. 21 is an enlarged perspective view of a push piece of the vanity case in FIG. 20;
FIG. 22 is a fragmentary perspective view illustrating a nose of the vanity case;
FIG. 23 is an enlarged fragmentary view of the vanity case;
FIG. 24 is a similar view showing an operation of the push piece;
FIG. 25 is also a view similar to FIG. 23 showing a modified, reverse arrangement;
FIG. 26 is a fragmentary sectioned view of a vanity case according to still another embodiment of the invention;
FIG. 27 is a perspective view showing a push piece in FIG. 26;
FIG. 28 is a view similar to FIG. 26 showing an operation of the push piece;
FIG. 29 is a perspective view of a push piece according to further embodiment of the invention; and
FIGS. 30 and 31 are fragmentary sectioned views of a vanity case incorporating the push piece of FIG. 29.
DETAILED DESCRIPTION OF THE INVENTION
Referring first to FIGS. 1 to 4 of the drawings, a vanity case 10 includes a receptacle member 12 having a concave portion 14 formed on the upper surface of the receptacle for containing cosmetic material. The front marginal portion of the receptacle 12 is centrally provided with a box-like recess 16 which opens in an upward direction. A first latch tongue 18 is formed on an inner vertical surface 20 defining the recess 16. The receptacle 12 is hinged at its rear end and by means of a pin 22 with a cover member 24 which has a mirror 26 attached thereto. A nose 28 extends downwardly from the cover 24 at a position corresponding to the recess 16, and a second latch tongue 30 is formed on the nose 28 to face the first one 18. The arrangements are such that when the cover 24 is closed over the receptacle 12, the latch tongues 18 and 30 engage with each other to thereby maintain the cover 24 in the closed position.
The front wall 32 defining the recess 16 is drilled or otherwise formed to have a hole 34 that is aligned with a slit 36 extending rearwardly from the inner wall 20 of the recess 16. Slidably fitted through the hole 34 is a plate-like body 40 of a push piece 38 which extends across the recess 16 and is also slidably fitted in the slit 36. As shown in FIG. 2, the push piece 38 comprises the body 40 having a center opening 42 formed therethrough, and an arm 44 which is connected at one end thereof to the rear surface defining the opening 42 at a connected section 46 in such a manner that the arm 44 may be swingable relative to the body 40 in a direction toward and away from the opening 42 and that the arm normally extends forwardly and downwardly. In the illustrated embodiment, the push piece 38 is integrally molded of synthetic resin material having the property of flexibility, and the connecting section 46 is formed thin to permit the swinging motion of the arm 44 relative to body 40.
In assembly, the push piece 38 is inserted through the hole 34 with the arm 44 being manually held within the opening 42, and is secured to the receptacle 12 by a projection or a stopper 48 formed on the lower surface of the body 40 adjacent the front of opening 42. When the cover 24 is in the closed position of FIG. 3, the stopper 48 engages with the inner surface of front wall 32 to project the front end of the body 40 beyond the wall 32. A lower portion of the nose 28 is positioned within the opening 42 and its lower inner end is in contact with the upper surface of the arm 44. The lower surface of the arm 44 is close to a corner 50 defined between the slit 36 and the vertical surface 20.
In order to open the cover 24, the front end of the body 40 is pushed inwardly. As the body 40 moves inward, the lower surface of arm 44 abuts against the corner 50 and is raised toward the opening 42. With this swinging motion, the arm upper surface presses the lower inner end of the nose 28 upwardly and forwardly to thereby release the engagement between the first and second latch tongues 18 and 30, as shown in FIG. 4. Because the forwardly directed pressure to the nose 28 weakens such engagement, the latch release operation can be made with a small force. Upon removal of the force applied to the body 40, the push piece 38 returns to its normal position due to a resilient force exerted in the section 46.
It should be noted here that the push piece may be mounted on the cover 24, and one might imagine such arrangements by viewing the figures upside down. Also, it is not essentially necessary that the nose 28 enter into the opening 42 in the closed position of the cover. The lower end of the nose may assume a position above the opening and the arm may swing until its upper surface comes to a level above the opening. A bulged lower surface of the arm will enable such a large stroke of swinging motion. Further, the arm lower surface may abut against any portion other than the corner 50. For example, such corner may be chamfered and provided with a projection extending toward the arm for contact therewith.
FIG. 5 illustrates a push piece 70 according to another embodiment of the invention, which includes a front wall 72 and side walls 74--74 defining a U-shape in plan view. A plate-like body 76 extends rearwardly from a vertical center of the front wall 72 and is formed with an opening 78 below which an arm 80 is arranged. This arm 80 is of an inverted L-shape comprising a horizontal portion 82 and a vertical portion 84 joined together at a corner 86 at which the arm 80 is integrally and swingably connected to the rear surface defining the opening 78 such that the upper surface of horizontal portion 82 normally extends substantially along the lower end of the opening 78.
The push piece 70 is mounted in an upwardly and forwardly opened recess 88 of the receptacle 12 with the rear end of body 76 being loosely fitted in the slit 36. Provided on the side walls 74 are projections 90 which are fitted in grooves 92 on the side surfaces defining the recess 88 in such a manner as to permit sliding movement of the push piece 70. When the cover 24 is maintained in the closed position as shown in FIG. 6, the arm horizontal portion 82 is close to the lower end of the nose 28 extending into the opening 78 while the vertical portion 84 is at its lower portion closely adjacent a corner 94 that is provided by a step 96 on the inner surface 20.
By pushing the front wall 72 inwardly, the push piece 70 moves while being guided by the grooves 92 and slit 36. This movement causes the vertical portion 84 to abut against the corner 92, followed by swinging or tilting of the arm 80 relative to the body 76. Therefore, the horizontal portion 82 presses the nose 28 upwardly to release the engagement between the latch tongues 18 and 30, as seen from FIG. 7.
In the present invention one of the latch tongues may be formed on the push piece, and several examples are illustrated in the drawings.
A push piece 100 in FIG. 8 is similar to that of FIG. 2 except that it has a pawl 102 extending upwardly from the body 40 at a position adjacent the rear end of the opening 42 and that a pair of resilient wings 104 extend from the rear side surfaces of the body 40 to project outwardly and rearwardly. When the push piece 100 is mounted in the recess 16 of the receptacle 12, the rear ends of wings 104 abut against a wall of a tray 108, which also defines the recess 16, to urge the body 40 forwardly where a first latch tongue 106 formed on the pawl 102 engages with the second tongue 30 to keep the cover 24 in the closed position of FIG. 9. A step 110 is formed on the lower surface of body 40 to restrain the forward displacement of the push piece 100. The tray 108 has a front margin 112 which conceals the recess 16 and has a through-hole 114 to permit the nose 28 to enter into the recess 16.
An inwardly directed pressure applied to the front end of body 40 causes the push piece 100 to retract against the resilient force of wings 104, resulting in the first latch tongue 106 separating from the second one 30 to release the engagement. At the same time, the arm 44 is raised into the opening 42 and presses the nose 28 upwardly so that the cover 24 lifts up sufficiently for a subsequent manual opening operation (FIG. 10). If desired, the arm 44 may normally abut against the corner 50 so that, upon inward movement of the push piece 100, the arm presses the nose 28 before the engagement of latch tongues is released. Such an arrangement makes it possible to open the cover 24 to a larger angle as the second latch tongue 30 is disengaged from the first one 18 by a snap action.
FIG. 11 shows a push piece 120 which is similar to the push piece 70 of FIG. 5 but includes a first latch tongue 122 and resilient wings 124 as in the example just described above. The operation of this push piece 120 will be apparent from FIGS. 6, 7, 9 and 10, and further description is therefore omitted.
A push piece 130 in FIG. 12 comprises a plate-like body 132 having a U-shape in plan view to define an opening 134, a cross bar 136 extending between the rear ends of arms of the body 132 and having a first latch tongue 138 at its front surface, and an arm 140 integral with the bar 138 through a thin flexible section 142 and having a base portion 144 and a hook portion 146 which is bent substantially at a right angle relative to the base portion 144. This push piece is integrally molded in the shape shown in FIGS. 12 and 13 wherein the base portion 144 of arm 140 extends rearwardly parallel with the body 132 and the hook portion 146 extends downwardly. Before assembly, the arm 140 is folded at 142 so that the base portion 144 extends forwardly and downwardly to position the end of hook portion 146 within the opening 134, as illustrated in FIG. 14. When the push piece 130 is mounted in the recess 16 of the receptacle 12, the arm base portion 144 abuts against the corner 50 and urges the push piece 130 forwardly to engage a step 148 on the body 132 with the front wall 32 defining the recess 16.
The cover 24 is maintained in the closed position by engagement of its latch tongue 30 with the first latch tongue 138 of the push piece 130. The arm base portion 144 is below the nose 28 while its hook portion 146 is forward of the nose 28 with a substantial space therebetween (FIG. 15). With these arrangements, when the body 132 is pushed inwardly, the cross bar 136 moves in a direction away from the nose 28 to release the engagement and, at the same time, the corner 50 causes the arm 140 to swing about the section 142 so that the hook portion 146 is close to the lower portion of the nose 28 as seen from FIG. 16. Further inward movement of the push piece 130 results in the hook portion 146 lifting the nose 28 to open the cover 24 (FIG. 17). The push piece 130, upon removal of the pressure, will return to its normal position by a resilient force exerted at the section 142. The return movement may be promoted by providing resilient wings such as 104 in FIG. 8 which wings also can ensure stable engagement of the latch tongues.
In a slightly modified arrangement of FIGS. 18 and 19, the arm hook portion 146 normally is closely adjacent to the front lower edge of the nose 28 so that, upon inward movement of the push piece 130, the hook portion 146 starts to press the nose 28 upwardly before the engagement is released. This results in an elastic deformation of the arm base portion 144, which will spring the nose 28 upwardly immediately after the first latch tongue 138 is disengaged from the second one 30.
The present invention is also applicable to a "three parts" vanity case having a tray disposed between the receptacle and cover to provide two chambers for containing cosmetic tools such as a puff along with the cosmetic material. One example thereof is illustrated in FIG. 20 in which a tray 150 as well as the cover 24 is hinged with the receptacle 12 at rear ends thereof. A first chamber 152 is defined in the receptacle 12 to contain a puff while a second chamber 154 is defined in the tray 150 to contain cosmetic material. The front marginal portion of the tray 150 is formed with a through-hole 156 which permits a nose 158 of the cover 24 to extend therethrough into a recess 162 of the receptacle 12 where a second latch tongue 160 on the nose 158 is engaged with a first tongue 164 on the inner wall defining the recess 162.
A slit 166 extends from the front edge of the tray 150 to a portion near the second chamber 154, and a push piece 168 is slidably fitted in the slit 166 across the through-hole 156. As best shown in FIG. 21, this push piece 168 comprises a plate-like body 170 having a center opening 172 which is aligned with the through-hole 156, and a pair of spaced arms 174 extending in the opening 172. Each arm 174 is connected to the upper end of the rear wall defining the opening 172 through a thin flexible section 176 that allows swinging movement of the arm 174. Normally, the base portion of the arm 174 extends downwardly and forwardly and its end portion includes a flat surface 178 substantially parallel with the upper surface of the body 170. The nose 158 has shoulders 180 (FIG. 22) to permit the lower portion of nose 158 to pass through a space between the arms 174. Thus, when the cover 24 is closed over the receptacle 12, the flat surfaces 178 of arms 174 abut the shoulders 180. Also, the downwardly inclined lower surfaces of the arms 174 are in contact with a corner 182 defined between the slit 166 and the rear end of the hole 156, as seen from FIG. 23.
The push piece 168 is slidably moved rearwardly when its front end projecting from the front edge of the tray 150 is pushed. This movement causes the arms 174 to swing upwardly about the sections 176, whereby the flat surfaces 178 press the nose 158 at the shoulders 180 to release the engagement of the latch tongues 160 and 164 (FIG. 24).
The above arrangements may be reversed, that is, the nose 158 may be provided on the receptacle 12 to extend through the tray 150 into the recess 162 in the cover 24 and the arms 174 may be adapted to press down the nose 158 when the push piece 168 is moved rearwardly. See FIG. 25. Also, the push piece 168 may be provided with resilient wings such as 104 in FIG. 8 to urge the body 170 forwardly.
In a modified example illustrated in FIGS. 26 through 28, the tray 150 has third and fourth latch tongues 182 and 184 which are formed on the inner surface defining the through-hole 156 at positions above and below the slit 166, respectively, and which are offset relative to each other in the transverse direction. The third latch tongue 182 is arranged to engage with a first tongue 186 that is formed on a first nose 188 extending upward from the receptacle 12 to maintain the tray 150 in the closed position, while the fourth latch tongue 184 is adapted to keep the cover 24 in the closed position through engagement with a second tongue 190 that is formed on a second nose 192 extending downward from the cover 24. A push piece 194 has first and second arms 196 and 198 arranged side by side in a center opening 200 and aligned in opposite directions. Thus, the first arm 196 is connected through a thin section 202 to the lower end of the rear wall and extends upwardly and forwardly to provide a downwardly facing flat surface 204, while the second arm 198 connected at 206 to the upper end of the rear wall extends downwardly and forwardly to provide an upwardly facing flat surface 208.
When the vanity case is in the closed position of FIG. 26, the first arm 196 is closely adjacent the upper end of first nose 188 at the flat surface 204 and abuts at the inclined upper surface against a corner 210 defined between the inner surface of the through-hole 156 and the upper surface of the slit 166. Also, the second arm 198 is closely adjacent the lower end of second nose 192 at the flat surface 208 and abuts at the inclined lower surface against a corner 212 between the through-hole 156 and the slit lower surface. An inward movement of the push piece 194 causes the first arm 196 to swing downwardly and the second arm 198 to swing in the opposite direction, whereby the flat surfaces 204 and 208 press the noses 188 and 192 downwardly and upwardly, respectively. Thus, the engagements between 182 and 186 and between 184 and 190 are released simultaneously to open the cover 24 and the tray 150. If desired, engagement release timings may be varied so that the inward movement of the push piece 194 first opens the cover 24 and then the tray 150, or vice versa. This can be achieved by, for example, differentiating longitudinal positions of the corners 210 and 212.
The third and fourth latch tongues may be provided on the push piece instead of on the tray, as shown in FIGS. 29 through 31. The third latch tongue 222 is formed on a first pawl 224 which extends downwardly from the rear wall of a push piece 220 adjacent the section 202, and the fourth latch tongue 226 is formed on a second pawl 228 extending upwardly adjacent the section 206. The tray 150 has first and second cavities 230 and 232 that are formed on the inner surface defining the through-hole 156 at positions corresponding to the first and second pawls 224 and 228, respectively, to permit the sliding movement thereof. With these arrangements, the inward movement of the push piece 220 separates its latch tongues 222 and 226 away from the first and second tongues 186 and 190, respectively, to release the engagements. At the same time, the first arm 196 presses down the receptacle 12 through the nose 188 while the second arm 198 presses up the cover 24 through the nose 192. As in the example of FIG. 8, the push piece 220 may be provided with resilient wings for normally urging the piece forwardly.
Although the present invention has been described with reference to preferred embodiments thereof, many modifications and alterations may be made within the spirit of the invention. | In a vanity case including a receptacle, a cover hinged with the receptacle and latch members for maintaining the cover in a closed position, a push piece is provided which is slidably movable along the longitudinal direction of the vanity case. The push piece has a center opening and an arm swingably connected to a rear wall defining the center opening, the arm having a portion extending forwardly from the rear wall and adjacent at least one of the receptacle and cover in the closed position. A stationary abutment is provided for, upon rearward movement of the push piece, abutting against the arm and causing it to swing relative to the rear wall with the front portion of the arm moving in the center opening, thereby forcing the receptacle and cover away from each other. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. Ser. No. 10/260,465, filed Oct. 1, 2002.
FIELD OF THE INVENTION
The present invention relates to removal of SO x and NO x and mercury with oxidants, and more particularly, the present invention relates to removal of SO x , NO x , and Hg with staged gas/liquid contact.
BACKGROUND OF THE INVENTION
In the pollution control field, several approaches are used to remove sulfur oxides and other contaminants from a flue gas produced by the burning of a fossil fuel in order to comply with Federal and State emissions requirements. One approach involves locating and utilizing fossil fuels lower in sulfur content and/or other contaminants. A second approach involves removing or reducing the sulfur content and/or other contaminants in the fuel, prior to combustion, via mechanical and/or chemical processes. A major disadvantage to the second approach is the limited cost effectiveness of the mechanical and/or chemical processing required to achieve the mandated reduction levels of sulfur oxides and/or other contaminants.
By and large, the most widely used approaches to removing sulfur oxides and/or other contaminants from flue gas involve post-combustion clean up of the flue gas. Several methods have been developed to remove the SO 2 species from flue gases.
A first method for removing SO 2 from flue gas involves either mixing dry alkali material with the fuel prior to combustion, or injection of pulverized alkali material directly into the hot combustion gases to remove sulfur oxides and other contaminants via absorption or absorption followed by oxidation. Major disadvantages of this first method include: fouling of heat transfer surfaces (which then requires more frequent soot blowing of these heat transfer surfaces), low to moderate removal efficiencies, poor reagent utilization, and increased particulate loading in the combustion gases which may require additional conditioning (i.e. humidification or sulfur trioxide injection) of the gas if an electrostatic precipitator is used for downstream particulate collection.
A second method for removing SO 2 from flue gas, collectively referred to as wet chemical absorption processes and also known as wet scrubbing, involves “washing” the hot flue gases with an aqueous alkaline solution or slurry in a gas-liquid contact device to remove sulfur oxides and other contaminants. Major disadvantages associated with these wet scrubbing processes include: the loss of liquid both to the atmosphere (i.e., due to saturation of the flue gas and mist carry-over) and to the sludge produced in the process; and the economics associated with the construction materials for the absorber module itself and all related auxiliary downstream equipment (i.e., primary/secondary dewatering and waste water treatment subsystems). A typical wet scrubbing system is shown in FIG. 1 .
A third method, collectively referred to as spray drying chemical absorption processes and also known as dry scrubbing, involves spraying an aqueous alkaline solution or slurry which has been finely atomized via mechanical, dual-fluid or rotary type atomizers, into the hot flue gases to remove sulfur oxides and other contaminants. Major disadvantages associated with these dry scrubbing processes include: moderate to high gas-side pressure drop across the spray dryer gas inlet distribution device, and limitations on the spray down temperature (i.e., the approach to flue gas saturation temperature) required to maintain controlled operations.
There are several methods for controlling NO x emissions. Selective Catalytic Reduction (SCR) is the most common method. In these processes, ammonia is injected and mixed with the flue gas at low to medium temperatures. The mixture then flows across a catalyst (often vanadium based over a stainless steel substrate) and the N x is reduced to N 2 . The problems with SCR systems is the high initial cost, high cost of ammonia which is thermally or chemically decomposed, and the introduction of ammonia into the gas stream causing problems with the formation of ammonium bisulfate and ammonia slip the atmosphere. Selective Non-catalytic Reduction (SNCR) methods are also employed. In these processes ammonia or urea in injected into hot flue gases resulting with a direct reaction forming N 2 . The problems with SNCR systems is the challenges with mixing and maintaining prober residence time and operating conditions for the reactions to take place optimally, sensitivity to changes in operating load, the high cost of ammonia which is thermally or chemically decomposed (even more than SCRs), and the introduction of ammonia into the gas stream causing problems with the formation of ammonium bisulfate and ammonia slip (as high as 50 ppm or higher) to the atmosphere.
NO x removal through injection of sodium bicarbonate (NaHCO 3 ) has been demonstrated by NaTec and others.
In the prior art for wet chemical NO x reduction, the use of oxidants such as hydrogen peroxide is employed. Hydrogen peroxide is an oxidizing agent for organic and inorganic chemical processing as well as semi-conductor, applications bleach for textiles and pulp, and a treatment for municipal and industrial waste. Hydrogen Peroxide (H 2 O 2 ) is an effective means of scrubbing Nitrogen Oxides. It has been used for many years. The use of H 2 O 2 and HNO 3 to scrub both NO and NO 2 is an attractive option because the combination handles widely varying rates of NO to NO 2 , adds no contaminants to the scrubbing solution or blow-down/waste stream and allows a commercial product to be recovered from the process, i.e. nitric acid or ammonium nitrate.
Gas scrubbing is another common form of NO x treatment, with sodium hydroxide being the conventional scrubbing medium. However, the absorbed NO x is converted to nitrite and nitrate which may present wastewater disposal problems. Scrubbing solutions containing hydrogen peroxide are also effective at removing NO x , and can afford benefits not available with NaOH. For example, H 2 O 2 adds no contaminants to the scrubbing solution and so allows commercial products to be recovered from the process, e.g., nitric acid. In its simplest application, H 2 O 2 and nitric acid are used to scrub both nitric oxide (NO) and nitrogen dioxide (NO 2 )—the chief components of NO x from many utility and industrial sources.
There are several other processes which also use hydrogen peroxide to remove NO x . The Kanto Denka process employs a scrubbing solution containing 0.2% hydrogen peroxide and 10% nitric acid while the Nikon process uses a 10% sodium hydroxide solution containing 3.5% hydrogen peroxide. A fourth process, the Ozawa process, scrubs NO x by spraying a hydrogen peroxide solution into the exhaust gas stream. The liquid is then separated from the gas stream, and the nitric acid formed is neutralized with potassium hydroxide. The excess potassium nitrate is crystallized out, and the solution reused after recharging with hydrogen. In addition to the methods cited above in which NO x is oxidized to nitric acid or nitrate salts, a series of Japanese patents describe processes and equipment for reducing NO x to nitrogen using hydrogen peroxide and ammonia.
Also worth mentioning is the fact that H 2 O 2 is used for the measurement of Nitrogen Oxide in the Standard Reference Method 7 of the Code of Federal Regulations (CFR) promulgated test methods published in the Federal Register as final rules by the US Environmental Protection Agency (EPA). In this procedure, an H 2 O 2 solution is used in a flask to effectively capture the NO x . This, however is a slow reaction that requires several hours to complete.
There are two primary reasons that H 2 O 2 has not gained widespread use as a reagent for removal of NO x in utility and large industrial applications. The first is that it is not a selective oxidant. Most of these sources also contain other species, primarily, SO 2 which are also effectively removed with hydrogen peroxide. Thus, a large quantity of H 2 O 2 would be required compared to the amount of NO x removal sought. Even after a limestone scrubber, the amount of SO 2 present in flue gas may be equal to or greater than the amount of NO x .
The second reason that H 2 O 2 has not gained widespread use is the cost, especially when much more is required due to reactions with SO 2 , for example, which can be better done prior to the H 2 O 2 stage.
The overall reactions are:
3H 2 O 2 +2NO→2HNO 3 +2H 2 O 1)
H 2 O 2 +2NO 2 →2HNO 3 2)
H 2 O 2 +SO 2 →H 2 SO 4 3)
Oxidation utilizing gases have been demonstrated in the art. It has been shown that over 90% of gas phase NO can be converted to NO 2 rapidly by ClO 2 at an applied rate of approximately 1.2 kg ClO 2 /kg NO. This of course requires proper mixing conditions. ClO 2 is a much stronger oxidizer than hydrogen peroxide, sodium chlorate or sodium chlorite and would be a preferred oxidizer. Ozone is also a possibility, but has orders of magnitude greater capital costs relative to ClO 2 generators.
Sulfur dioxide reacts with chlorine dioxide in the gas phase to form sulfuric and hydrochloric acid.
2ClO 2 +5SO 2 +6H 2 O→5H 2 SO 4 +2HCl 4)
Assuming SO 2 is the dominant species in the ClO 2 reaction in the presence of SO 2 and NO, then it is advisable, according to this invention, to add ClO 2 after having scrubbed out SO x to keep the economics of adding ClO 2 good.
A different process employs a proprietary oxidizing compound plus dilute sulfuric acid in a first stage and an irreversible process involving proprietary solutions and chemistries in a second stage. The system operates at greater than 99% efficiency on both NO and NO 2 and will accommodate ambient temperature gas streams.
The prior art also does not teach simultaneous removal of mercury and NO x , especially elemental mercury (Hg°) removal. The prior art does teach limited capture of mercury using activated carbon and capture of oxidized mercury (Hg +2 such as in the form of HgCl 2 ) (U.S. Pat. No. 6,503,470 to Nolan, et al.) in wet scrubbers that use an alkali reagent. This process also uses additives such as sodium hydrogen sulfide (NaHS) or other sulfides to chemically bind with the mercury to form compounds such as HgS.
SUMMARY OF THE INVENTION
One object of one embodiment of the present invention is to provide an improved method for scrubbing flue gas streams.
A further object of one embodiment of the present invention is to provide a method of scrubbing Hg compounds from a flue gas stream, comprising a scrubbing operation, including: contacting a flue gas stream containing Hg, SO x and NO x compounds with a sorbent for removing at least a portion of said SO x , Hg and NO x compounds present in said stream to provide a partially cleaned flue gas stream; and contacting said partially cleaned flue gas stream with an oxidant to oxidize and capture substantially all residual Hg remaining in said stream.
Yet another object of one embodiment of the present invention is to provide a method of scrubbing NO x compounds from a flue gas stream containing said NO x compounds, a scrubbing operation, including: contacting a flue gas stream containing SO x and NO x compounds with a sorbent for removing at least a portion of said SO x and NO x compounds present in said stream to provide a partially cleaned flue gas stream; and contacting said partially cleaned flue gas stream with an oxidant to oxidize and capture substantially all residual NO x remaining in said stream.
A host of advantages are realized by practicing the methodology of the invention. One advantage is that a high removal of SO 2 and NO x (NO, NO 2 , and dimers) is achieved with essentially all of the acid gas and air toxics (including NO x ) in the flue gas being removed. Particularly convenient is the fact that NO x is removed without the use of ammonia and no SCR (Selective Catalytic Reduction) system is required for NO x removal. The methodology also results in the high removal of Hg without the use of expensive activated carbon systems; in the preferred embodiment, all emissions removal is accomplished in a single, staged tower.
It has been found that the oxidant will also effectively remove any SO 2 in the flue gas with the overall cost of this ultra high removal system being lower than a system with multiple vessels.
In terms of other features, less physical space is required than conventional multi-step processes which would employ separate vessels and much more equipment in the gas stream; the amount of oxidant required is reduced, since almost all the sulfur compounds and some of the NO x and Hg are removed prior to the oxidant stage.
The process permits many choices for reagents for SO 2 control in the first add-on stage with sodium alkalis being the preferred reagents due to gas phase reactions in the stage, production of sodium sulfate, the ability to regenerate the sodium alkali, and conveniently, carbon injection equipment is not required as Hg and other air toxics are removed by the staged process steps.
Further advantages include: each stage can be custom designed to meet the pollutant removal characteristics of the constituents removed in each individual stage; the chemistry of each stage is independently controlled and monitored to optimize the performance; each stage is isolated to prevent contamination of reagents/solutions; and the solutions in each stage are handled separately.
Having thus described the invention, reference will now be made to the accompanying drawings illustrating preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a prior art scrubber arrangement;
FIG. 2 is a scrubber arrangement according to the present invention;
FIG. 3 is a prior scrubber arrangement incorporating a wet electrostatic precipitator (WESP) for the purpose of removing condensables, like H 2 SO 4 which forms from SO 3 gas and water;
FIG. 4 is a graphical representation of data in accordance with the present invention; and
FIG. 5 is a further graphical representation of data in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Wet scrubbing systems such as that shown on FIG. 1 and globally denoted by numeral 10 use lime, limestone, soda ash, sodium, magnesium, and calcium or other compounds for scrubbing. They also can employ any of a number of additives to enhance removal, control chemistry, and reduce chemical scale. These systems are adequate at removing SO 2 up to maybe 90-98%, but do not effectively remove NO x or Hg.
In the combined system of the present invention, the flue gas is scrubbed by wet scrubbing using prior art technologies like that shown on FIG. 1 for partial removal of SO 2 (partial removal means less than 100% or typically 90-95% such as is known in the prior art for calcium based scrubbers).
The gas could be, optionally, conditioned by injection of absorbents, reagents, or sorbents to reduce a portion of the inlet SO 3 . Some sulfur dioxide, hydrochloric acid, NO x or other acid gases may also be removed by the injection. This can be by wet or dry injection with almost any alkali at any of several possible and known locations or temperature zones from the source of the flue gas to the scrubber inlet. However, dry sodium bicarbonate injection is preferred since it will react with the SO 3 , NO x and SO 2 and other acid gasses including HCl, HF, H 2 S, etc. in the gas stream. When injection of sorbents is employed, the need for a wet electrostatic precipitator such as that shown on FIG. 3 is eliminated. H 2 SO 4 is not formed since SO 3 is effectively removed upstream of the wet scrubbing system.
Following the optional injection step, SO 2 and acidic NO x compounds such as NO 2 , N 2 O 3 and N 2 O 5 and their associated dimmers, i.e. N 2 O 4 are removed in the wet scrubber. In the prior art with sodium bicarbonate injection, the conversion of NO to NO 2 was considered undesirable since the NO 2 was a brown gas that was not captured by the downstream equipment. In this case, the wet scrubber effectively captures some of the NO 2 , N 2 O 5 , etc. Some of the NO is captured directly by the sodium bicarbonate.
In the prior art, including U.S. Pat. No. 6,143,263 and U.S. Pat. No. 6,303,083, Method and System for SO 2 and SO 3 Control by Dry Sorbent/Reagent Injection, and Wet Scrubbing, there is no teaching for NO x removal in any form as the NO x is known to be primarily in the form of NO which is not effectively captured with conventional based sorbents such as lime, limestone, or sodium.
The present invention is a one to three step add-on technology. This applies to all scrubbing systems for gases that contain SO 2 , NO x , and Hg such as from the combustion of coal or other industrial fuels or from chemical processes. This also applies to both new applications or modifications of existing units.
For the one stage add-on step, all or almost all SO 2 is removed by the prior art system such as a high efficiency scrubber that employs a reagent based on sodium, magnesium, buffered calcium, etc. High removal of SO 2 is not necessary, but is preferred. If the SO 2 removal is low, then it will be removed by the oxidant. This will require a significant quantity of a higher cost reactant.
For a 2-stage add-on step, the first a stage is added to effectively remove all or almost all of the remaining SO 2 . This uses a tray like a bubble cap tray (not shown) or a separate vessel (not shown) to keep the 2 nd -stage SO 2 reagent stream separate from the lower stage acid gas absorber stage. This is done preferably, using a soluble scrubbing solution such as a sodium or magnesium based reagent (hydroxide, carbonate, sulfite, bicarbonate, bisulfite, etc. and may include buffering agents, additives, organic acids, etc.) with the appropriate mass transfer surfaces including any combination of sprays, packing, trays, etc.
Therefore, for both cases, all or almost all of the SO 2 is removed prior to the oxidant stage.
In the oxidant stage, NO x (primarily in the form of NO, NO 2 , or other dimers) and mercury (elemental and oxidized) are removed. Like the first stage of the 2-stage add-on step, this uses a tray like a bubble cap tray or a separate vessel (neither of which are shown) to keep the reagent, in this case an oxidant stream, separate from the lower stages. Mass transfer surfaces such as additional trays, sprays or packing are added as required. The result is that the gas leaving this stage is essentially free of all SO X and has at up to 90% or more of the mercury and NO x removed. This eliminates Hg, SO X , and NO x contamination in the final stage.
An optional add-on stage is used as a final wash. This would be used to make sure any byproduct from the oxidant such as chlorine gas, NO 2 , etc. is washed from the flue gas. The final wash, if required, would be with water or an appropriate solution.
A preferred embodiment (see FIG. 4 ) therefore consists of 2 to 5 or more stages. In a five stage system, the first stage is a dry injection step. The second stage is the wet acid gas scrubber using conventional steps known in the art and denoted by numeral 12 . The third stage is a polishing step to remove the remaining SO 2 . The preferred embodiment of the third stage (first add-on stage) is a reaction zone that uses a sodium carbonate (Na 2 CO 3 ), caustic soda (NaOH) or sodium bicarbonate (NaHCO 3 ) reactant. This would produce sodium sulfate by the following overall reactions:
2NaHCO 3 +SO 2 +½O 2 →Na 2 SO 4 +2CO 2 ↑+H 2 O 5)
Na 2 CO 3 +SO 2 +½O 2 →Na 2 SO 4 +CO 2 ↑+H 2 O 6)
2NaOH+SO 2 +½O 2 →Na 2 SO 4 +H 2 O 7)
The sodium carbonate, caustic soda, or sodium bicarbonate (or other reactants) can be purchased. Sodium bicarbonate can be regenerated on site using the processes developed by Airborne Pollution Control. Caustic soda can be produced on site using electrochemical methods from sodium sulfate. In this case, sodium sulfate is split and reacted with ammonia to produce NaOH and (NH 4 ) 2 SO 4 . The NaOH is used in the scrubber and the (NH 4 ) 2 SO 4 can be sold as a fertilizer.
The forth stage is the oxidant stage is used to remove NO x and/or mercury. One embodiment of the oxidant stage would be an integral reaction zone that recirculates an aqueous solution of oxidant and reaction products to effectively remove all the NO x and much of the mercury, simultaneously. No sulfur oxides would be removed in this step as they are effectively removed prior to the oxidant stage.
The fifth stage is the final wash.
Other embodiments would use 2, 3, 4, 5 or more stages depending upon the pollutants that will be removed and the operating conditions. For example, Stage 1 of the preferred embodiment, would not be required if SO 3 was not present, Stages 1 and 2 are not required if there is no SO x present, and Stage 5 is not required if species that require a final wash are not present. The oxidant would be selected depending upon the desired level of removal of NO x and/or Hg.
The following is a partial list of oxidants that are useful for capture of NO x and/or Hg or Hg compounds:
1) Hydrogen Peroxide 2) Hydrogen Peroxide/Nitric Acid Solution (H 2 O 2 /HNO 3 ) 3) Hydrogen Peroxide/Nitric Acid/Hydrochloric Acid Solution (H 2 O 2 /HNO 3 /HCl) 4) Sodium Chlorate Solution (NaClO 3 ) 5) Sodium Chlorite Solution (NaClO 2) 6) Sodium Hypochlorite Solution (NaClO) 7) Sodium Perchlorite Solution (NaClO 4 ) 8) Chloric Acid Solution (HClO 3 ) 9) Oxone Solution (2KHSO 5 —KHSO 4 —K 2 SO 4 Triple Salt) 10) Potassium Chlorate Solution (KClO 3 ) 11) Potassium Chlorite Solution (KClO 2 ) 12) Potassium Hypochlorite Solution (KClO) 13) Potassium Perchlorite Solution (KClO 4 ) 14) Potassium Permanganate (KMnO 4 ) 15) Potassium Permanganate/Sodium Hydroxide Solution
other oxidants or combinations of oxidants are possible. Further, sodium carbonate and sodium bicarbonate or other alkalis can be substituted for the sodium hydroxide solutions used for pH adjustment and to provide the ions for complete reactions. Oxidants can be selected to remove just NO x , remove just Hg or simultaneously remove both NO x and Hg. Additionally, gaseous oxidants such as ozone, O 3 , or Chloride dioxide, ClO 2 , can be injected into the gas that has had all or most of the SO 2 removed. With proper mixing and sufficient residence, the oxidation of NO or Hg in the gas phase by gaseous oxidants occurs. Gaseous oxidants are capable of oxidizing NO not only to NO 2 but also to N 2 O 5 which rapidly reacts with water or alkaline solutions to form nitric acid or nitrates.
Bench-scale screening of potential solutions for capturing NO x and Hg° was performed using a simple gaseous mixture (Hg°+NO+NO 2 +CO 2 +H 2 O+N 2 +O 2 ) and an impinger sampling train similar to that described in the American Society of Testing and Materials Method D6784-02 (Ontario Hydro method). Testing has identified solutions that effectively removed both NO x and Hg°. The results are shown in the table below:
TABLE 1
BENCH SCALE TEST RESULTS
Hg Removal
NO x Removal or NO
(Hg Total
Solution
Conversion to NO 2
and Hg°)
Hydrogen Peroxide
Low
Low
Nitric Acid (40%) + Hydrogen
30-40%
30-40%
Peroxide
Acidified Potassium Permanganate
30-40%
~100%
Chloric Acid
Low
30-40%
0.1 M NaClO pH adjusted to 3.74
~100%
~100%
using HCl
0.25 mole/L KMnO 4 + 2.5 mole/L
~98% (about 4 ppm
~100%
NaOH (pH of 11.3)
passed through)
0.1 M NaClO, pH adjusted to 6
75-95%
~100%
NaClO pH adjusted to 5 using HCl
~70%
~100%
The results show that there are several possible solutions from which to choose. Even the situations that show medium removal ranges such as (Nitric Acid (40%)+Hydrogen Peroxide) or Acidified Potassium Permanganate will remove at higher rates with an appropriate modification to the mass transfer means. The oxidant selected, will then be based on economics, availability, desired level of capture, and/or desired end product.
Further results are shown on FIGS. 3 & 4 , with FIG. 3 illustrating mercury removal as a functioning time using NaClO at pH 5.73 and FIG. 4 illustrating mercury and NO x removal as a function of time using 0.1 M NaClO solution at pH 8. The proposed reactions with Sodium Hypochlorite (NaOCl) and NO x and Hg are:
2NO+3NaClO+2NaOH→2NaNO 3 +3NaCl+H 2 O 8)
2NO+3NaClO+Na 2 CO 3 →2NaNO 3 +3NaCl+CO 2 ↑ 9)
2NO+3NaClO+2NaHCO 3 →2NaNO 3 +3NaCl+2CO 2 ↑+H 2 O 10)
2NO 2 +NaClO+2NaOH→2NaNO 3 +NaCl+H 2 O 11)
2NO 2 +NaClO+Na 2 CO 3 →2NaNO 3 +NaCl+CO 2 ↑ 12)
2NO 2 +NaClO+2NaHCO 3 →2NaNO 3 +NaCl+2CO 2 ↑+H 2 O 13)
2Hg+4NaClO+2H 2 O→2HgCl 2 +4NaOH+O 2 14)
In these reactions, an additional source of sodium such as bicarbonate, carbonate or hydroxide is provided to balance the reaction and in order to limit the potentially deleterious reaction of liberating Cl 2 gas. Thus the washing step would not be required. Sodium Chlorite (NaClO 2 ), Sodium Chlorate (NaClO 3 ) and Sodium Perchlorite (NaClO 4 ) can also be used for removal of NO x and Hg.
The products of the NO x reactions can be regenerated by the Airborne Process™ by the reactions:
NaNO 3 +H 2 O+NH 3 +CO 2 →NaHCO 3 ↓+NH 4 NO 3 15)
NaCl+H 2 O+NH 3 +CO 2 →NaHCO 3 ↓+NH 4 Cl 16)
Although embodiments of the invention have been described above, it is not limited thereto and it will be apparent to those skilled in the art that numerous modifications form part of the present invention insofar as they do not depart from the spirit, nature and scope of the claimed and described invention. | A method of scrubbing mercury compounds and nitrogen oxides from a gas stream employing a scrubbing operation. The method involves the contact of the stream which contains mercury, SO x and NO x compounds with a sorbent to remove at least a portion of the latter compounds. This results in a partially cleaned stream. The method further involves contacting the latter stream with an oxidant to oxidize and remove substantially all residual nitrogen oxides, mercury and mercury compounds remaining in the stream. | 5 |
FIELD OF THE INVENTION
The present invention relates to a learning method for an automatic transmission of a vehicle and a system thereof, and more particularly, to a learning method and system for an automatic transmission of a vehicle when a down-shift is performed during an up-shift.
BACKGROUND OF THE INVENTION
A vehicle automatic transmission performs shifting to a target shift-speed by controlling a plurality of solenoid valves that in turn control hydraulic pressure based on a variety of factors related to vehicle driving, such as a vehicle speed and throttle valve open-angle. For instance, when a driver trans-positions a select lever into a desired shift range, a manual valve transforms its port configuration, and therefore hydraulic pressure from a hydraulic pump is delivered to corresponding friction elements under control of the solenoid valves.
In the process of controlling shifting of the shift-speed, there is an element to be released, which is originally engaged, and there is also an element to be engaged (referred to as “engaging element” hereinafter), which is originally disengaged. The timing for engaging and disengaging elements to be engaged and disengaged is important to enhance shift quality in an automatic transmission, therefore, much of the recent progress in shift control methods relates to providing proper engaging and disengaging timing of friction elements. The engaging and disengaging timing can be modulated by control of hydraulic pressure supplied to the friction element, and the hydraulic pressure is controlled by a hydraulic duty applied to the solenoid valves.
When the driver releases the accelerator pedal, a transmission control unit (referred to as “TCU” hereinafter) determines that a higher shift-speed is preferable, and accordingly an up-shift of the automatic transmission will occur, which is called a lift-foot-up shift. For example, when the accelerator pedal is released while the vehicle is being driven in a third shift-speed, with the select lever being disposed in a drive “D” range, the TCU starts a shift from the third shift-speed to a fourth shift-speed. However, if the accelerator pedal is depressed again before the up-shift is completed, the TCU must perform a down-shift to either the third shift-speed or a lower one.
When a down-shift is necessary when an up-shift has not been completed, the prior art usually performs the down-shift only after the up-shift is completed. This lengthens the period of time elapsed for shifting and therefore deteriorates acceleration of the vehicle. Further, even when the prior art starts a down-shift control while the up-shift is not complete, the prior art does not provide an appropriate learning method for the down-shift. This causes shift shock during the down-shift when clearance of the clutch has changed-due to abrasion or because of tolerance stack-up, and therefore deteriorates the durability of the automatic transmission.
SUMMARY OF THE INVENTION
The present invention provides a method and a system for learning a hydraulic duty for an engaging element of a down-shift, based on an amount of overrun incurred in the down-shift such that a minimal overrun is induced in the down-shift because of the learned hydraulic duty.
A learning system for an automatic transmission according to an embodiment of the invention comprises a revolution speed detector detecting at least one of engine revolution speed and turbine revolution speed; and a transmission control unit, wherein the transmission control unit performs a learning method according to the present invention.
A learning method for an automatic transmission according to a further embodiment of the invention comprises detecting an amount of overrun produced during a down-shift occurring in an up-shift; determining whether the amount of overrun is greater than a predetermined level; and modifying a hydraulic duty for an engaging element of the down-shift on the basis of the amount of overrun and a determination in whether the amount of overrun is greater than a predetermined level.
Preferably, modifying a hydraulic duty comprises performing one of adding or subtracting a correction value to the hydraulic duty, the correction value being calculated based on the amount of overrun. The correction value may be calculated as increasing as the difference between a amount of overrun and the predetermined level increases. More preferably, the correction value is added to the hydraulic duty when the amount of overrun is greater than the predetermined level, and subtracted from the hydraulic duty when the amount of overrun is less than the predetermined level. The predetermined level is preferably defined as a least amount of overrun such that a tie-up shock is not incurred.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention, and, together with the description, serve to explain the principles of the invention:
FIG. 1 is a block diagram of a learning system for an automatic transmission of a vehicle according to a preferred embodiment of the present invention;
FIG. 2 is a flowchart showing a learning method for an automatic transmission of a vehicle according to a preferred embodiment of the present invention;
FIG. 3 is a graph showing how a correction rate of a correction value is dependent on the amount of overrun according to a preferred embodiment of the present invention; and
FIG. 4 is a graph showing how an overrun of a down-shift is reduced as a learning process is multiply-performed, according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the present invention will hereinafter be described in detail with reference to the accompanying drawings.
As shown in FIG. 1, the learning system according to the embodiment of this invention includes a vehicle driving-state detecting unit 2 for detecting a plurality of factors related to the vehicle driving-state, a transmission control unit (referred to as “TCU” hereinafter) 20 for controlling a speed-shift based on the factors detected by the vehicle driving-state detecting unit 2 , and an actuator unit 18 for performing the speed-shift under the control of the TCU 20 . TCU 20 may include a memory and CPU as generally known in the art such that it may be programmed to contain and execute instructions for controlling actuator unit 18 according to the present invention as described herein.
The vehicle driving-state detecting unit 2 includes a throttle valve open-angle detector 4 , a vehicle speed detector 6 , a select lever position detector 8 , a hydraulic fluid temperature detector 10 , an engine-speed detector 12 , and pulse generators-A 14 and -B 16 .
The throttle valve open-angle detector 4 detects an open-angle of a throttle valve, the select lever position detector 8 detects the position of a select lever such as neutral “N”, drive “D”, second “2”, and low “L” ranges. The pulse generators 14 and 16 respectively detect a turbine-speed of a turbine disposed in a torque converter of the automatic transmission, and a revolution speed of-an output-shaft of the automatic transmission.
The actuator unit 18 , preferably disposed in the automatic transmission, includes a solenoid valve for controlling hydraulic pressure for a shift, and the TCU 20 controls shifting by sending a hydraulic duty signal to the solenoid valve.
FIG. 2 illustrates how the hydraulic duty is learned by the TCU 20 . When a down-shift occurs during an up-shift at step S 100 , the TCU 20 detects the revolution speed of the engine, or more preferably, the revolution speed of the transmission turbine at step S 110 . The TCU 20 then calculates an amount of overrun, produced during the down-shift, at the detected revolution speed at step S 120 . Accordingly, the TCU 20 determines whether the amount of overrun is larger than a predetermined level, for example, 30 rpm, at step S 130 . When the amount of overrun is determined to be larger than 30 rpm at step S 130 , the TCU 20 calculates a correction value |α| of the hydraulic duty Pr, and adds the correction value |α| to the current hydraulic duty Pr at step S 140 .
When the amount of overrun is determined not to be larger than 30 rpm at step S 130 , the TCU 20 calculates a correction value |α| of the hydraulic duty Pr, and subtracts the correction value |α| from the current hydraulic duty Pr at step S 150 .
The hydraulic duty Pr is a hydraulic duty for controlling hydraulic pressure supplied to an engaging element of the down-shift. If the correcting steps S 140 and S 150 are initially performed, current hydraulic duty Pr will be the same as an originally set value. The hydraulic duty Pr corrected at either step of S 140 and S 150 is used for a hydraulic duty for controlling a next down-shift. The correction value |α| depends on how much overrun has been detected at step S 110 , and FIG. 3 shows the dependency. As shown in FIG. 3, an exemplary correction rate for the correction value |α| increases as a difference between the amount of overrun and the predetermined level increases. As learning steps S 100 -S 150 are performed repeatedly, the amount of overrun will converge to the predetermined level of 30 rpm, because the hydraulic duty Pr is repeatedly learned. The actual correction value and correction rate will vary based on size or capacity of the engine or transmission as determined by a person of ordinary skill in the art in view of the teachings of the present invention. Preferably, the predetermined overrun speed (30 rpm in the example above) can be set based on the measured output torque profile of the transmission. Larger values, such as 50 or 100 rpm, may be selected, but factors such as a lower pressure to secure an improved shift feel must be balanced with the unacceptability of large overrun speeds. For these reasons, smaller predetermined overruns speeds are generally preferred; however, a person skilled in the art may calibrate this value in the event that the transmission torque profile is unacceptable, i.e., an undesirable level of shift shock occurs.
For example, using the correction rate as illustrated in FIG. 3, at an overrun of about 200 rpm, the correction value |α| is about 1%. Adjusting the duty control by +1% as in step s 140 may lead to a reduced overrun of about 80 rpm in a particularly sized engine. In this case, in a second iteration, a correction value of about 0.3% would be added to approach convergence with the predetermined overrun value of 30 rpm. In the event that the overrun correction caused a reduction in overrun to under 30 rpm, for example to 20 rpm, then a value of about −0.1% would be added in step s 150 to approach convergence.
A further example, with a different capacity transmission or engine is illustrated in FIG. 4 . In this example, when the amount of overrun is initially about 200 rpm, hydraulic duty is corrected by +2.5% and resultantly the amount of overrun is reduced to 80 rpm in a second performance of a down-shift. During the second performance of the down-shift, the hydraulic duty is learned still more, by an additional 1.0%, such that the hydraulic duty is corrected by a total of 3.5%. Resultantly, the amount of overrun is reduced to near the predetermined level, 30 rpm.
Even if no overrun is detected at step S 110 , the hydraulic duty Pr is learned such that eventually the amount of overrun will converge to the predetermined level, which decreases the possibility of tie-up of the transmission, and reduces shift-shock.
As shown above, this invention enables a more rapid shift and prevents a tie-up because a hydraulic duty for an engaging element in a down-shift is learned on the basis of an overrun, which enhances shift-feel and increases durability of an automatic transmission of a vehicle.
While this invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | In order to enable a more rapid shift and to prevent tie-up from occurring when a down-shift occurs during an up-shift, an amount of overrun produced during the down-shift is detected, and a hydraulic duty for an engaging element of the down-shift is modified by performing one of adding and subtracting a correction value, the correction value being calculated based on the detected amount of overrun, such that the amount of overrun will converge to a predetermined minimal level. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an optical card processing apparatus which uses a light beam to record information on and/or reproduce information from a card-shaped recording medium.
2. Description of Related Art
As shown in FIG. 7, a conventional optical card processing apparatus of this type includes a card holder 9 having a card holding section 90 on its top side, and a guide mechanism 91 on which the card holder 9 is reciprocatively mounted. The card holding section 90 is provided with strip-shaped card retaining plates 93 on both sides of the top of a card support plate 92, as shown in FIG. 8, and card insertion grooves 94 are formed between the card retaining plates 93 and the top side of the card support plate 92. When both side edges of an optical card 8 are inserted into the guide insertion grooves 94, these side edges of the optical card 8 are held in a pressed state to secure the card.
A reversibly rotatably drive motor 96 is connected to the card holder 9 via a belt 95. Situated above the card holder 9 is an optical head 97 for recording information on and/or reproducing information from the optical card 8. The optical head 97 has an objective lens (not shown) whose focusing is controlled in such a manner that an irradiating beam produced at recording/reproduction has its focal point formed on the surface of the information recording medium of the optical card 8 at all times. Accordingly, when the card holder 9 is reciprocated relative to the optical head 97 by the drive motor 96, recording information on and/or reproducing information from an information track of the optical card 8 is carried out while focusing control is performed in such a manner that a fluctuation in the distance between the card surface and the objective lens is made to approach zero. Such fluctuation is caused by deformation of the optical card 8 and vibration of the the same that occurs when the card holder is reciprocated.
FIG. 9 illustrates the entirety of the optical card 8 as well as a portion of the card shown in enlarged form. The optical card 8 undergoes a data reading (reproduction) or data writing (recording) operation performed by an optical processing apparatus. The optical card is not limited to that of the type which undergoes recording/reproduction optically but also covers optical cards of the type subjected to recording/reproducing electromagnetically. An information recording zone 80 of the optical card 8 is provided with a number of information recording tracks 81 defined by track guides 82. Bits representing information are recorded on these tracks 81 in the form of pits (in the case of a card capable of undergoing recording/reproduction optically). The track guides 82 are for the purpose of causing the recording/reproduction optical head to follow the tracks on the card (tracking control).
Since the card holder 9 is so arranged that the two longitudinal side edges of the four edges of the optical card 8 are held by the retaining plates 93, the front and rear edges of the optical card 8 are the free edges when the card is being held by the card holder 9. Consequently, in the event that the optical card sustains warping or curvature in such a manner that its four sides rise, as shown in FIG. 10a, or in such a manner that its front and rear side edges bow upwardly, as depicted in FIG. 10b recording/reproduction performance suffers. Specifically, the curvature cannot be corrected by the card holding section 90 and a large focal-point error is produced by such buckling at the time of recording/reproduction.
FIG. 8 illustrates the warped optical card 8 in a state held by the card holder 9. The state of the information recording zone 80 of the optical card 8 which appears between the retaining plates 93 is such that portions A, B near the front and rear edges of the card rise while the central portion C is recessed.
FIG. 11 illustrates conditions under which focal-point error is produced when reproducing recorded information from the optical card 8 wrapped as shown in FIG. 8. It will be appreciated that focal-point error fluctuates in dependence upon the deformation at the front and read edge portions A, B and the central portion C.
When the optical card 8 warped in this manner is conveyed back and forth, the degree of card vibration is great and therefore the focusing control mechanism within the optical head 97 cannot follow up the vibration. The result is a large focal-point error and poor recording/reproduction performance. In order to suppress the occurrence of this vibration, it is necessary to reduce the speed at which the card holder 9 is fed, but this makes it difficult raise the speed of the recording/reproduction operation.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide an optical card processing apparatus wherein the manner in which an optical card is held by a card holder is specially contrived to correct optical card deformation and suppress the occurrence of vibration, whereby focal-point error attributed to curvature and vibration of the card is reduced and feed velocity raised to realize high-speed recording/reproduction.
According to the present invention, the foregoing object is attained by providing an optical card processing apparatus for performing at least one of recording information on and reproducing information from a rectangular optical card by reciprocating a card holder, which holds the optical card, relative to an optical head, characterized in that the card holder is provided with holding means for holding, in a pressed state, at least three sides of the optical card.
When the optical card is set in the card holder, at least three sides of the card are held in a pressed state. Therefore, even if the card is deformed such as by undergoing warping or curvature, the deformation is sufficiently corrected. Moreover, in comparison with the conventional arrangement in which two sides of the card are held, there are fewer free ends of the card that are capable of vibrating.
As a result, curvature of the optical card and card vibration ascribable to is free ends are reduced, thereby diminishing focal-point error at recording/reproduction to improve recording/reproduction performance. In addition, the feed velocity of the card holder can be raised to make possible high-speed recording/reproduction.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view illustrating the internal mechanism of an optical card processing apparatus according to an apparatus of the present invention;
FIG. 2 is a sectional view longitudinally of the apparatus of FIG 1;
FIG. 3 is a sectional view transversely of the apparatus of FIG. 1;
FIG. 4 is a sectional view of a card holder and illustrates an optical card in the process of being received by the card holder;
FIG. 5 is a sectional view of the card holder and illustrates the optical card in a state held by the card holder;
FIG. 6 is a bottom view of the card holder and illustrates the optical card in a state held by the card holder;
FIG. 7 is a perspective view showing an optical card processing apparatus according to the prior art;
FIG. 8 is a perspective view of a prior-art card holder and shows a warped optical card in the held state;
FIG. 9 is a plan view of an optical card and shows an information recording zone in enlarged form;
FIGS. 10a and 10b are perspective views showing an optical card which has undergone curvature; and
FIG. 11 is a graph showing a change in focal-point error with the passage of time when reproducing recorded information from the optical card of FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 through 3 illustrate the internal mechanism of an optical card processing apparatus according to an embodiment of the present invention.
The optical card processing apparatus includes a case 10 having a card insertion slot 1, a pair of guide rods 11 arranged in parallel within the case 10 for reciprocatively supporting a card holder 2, an optical head 5 disposed below the holder traveling path on the side near the card inlet slot 1, and a holder feed mechanism 4 similarly disposed below the holder traveling path rearwardly of the optical head 5.
The guide rods 11 in the card holder 2 freely slidably support bearings 21 provided on both sides of the card holder 2, and the latter is further provided with a card holding mechanism 20 for holding, in a pressed state, the four sides of the rectangular card 8, namely the two longitudinal sides and the front and rear sides of the card.
The card holding mechanism 20 comprises a card support plate 22 constituting the bottom face of the card holder 2, a retaining plate 23 for pressing the optical card 8 against the card support plate 22, a pressurizing mechanism 24 for causing the retaining plate 23 to apply pressure to the card support plate 22, and a release mechanism 3 for urging the retaining plate 23 upward to release the optical card 8 from the held state.
The card support plate 22 is formed as a unitary body having a front wall 2a, rear wall 2b and longitudinal side walls 2c, 2d constituting the card holder 2, and the plate floor is formed to have a rectangular widow 25 in which the information recording zone 80 of the optical card 8 is situated. Accordingly, when the optical card 8 is set on the card support plate 22 with its information recording zone 80 facing downward, the two longitudinal sides of the optical card 8 are supported by two longitudinal side portions 22c, 22d of the card support plate 22, and the front and rear sides of the card are supported by front and rear end portions 22a, 22b of the card support plate 22.
The retaining plate 23 has a size corresponding to that of the optical card 8. One end of the retaining plate 23 is pivotally supported on the rear end portion 22b of the card support plate 22, and the other end of the retaining plate 23 is free to swing up and down. An arm member 26 projecting from one side of the retaining plate 23 to outside is attached to the retaining plate 23.
The pressuring mechanism 24 includes a mounting wall 27 spanning the two side walls 2c, 2d of the card holder 2, and two coil springs 28 disposed between the mounting wall 27 and the upper surface of the retaining plate 23 on both its longitudinal side portions.
The release mechanism 3 includes such components as a cam mechanism and solenoid, and is disposed on a side portion rearwardly of a card loading/ejecting mechanism 7, described later. The release mechanism 3 is equipped with a vertically operated actuating member 30. By elevating the actuating member 30, the arm member 26 of the retaining plate 23 is urged upwardly to tilt up the retaining plate 23. By lowering the actuating member 30, the upward urging force is eliminated and the retaining plate 23 is returned to the horizontal state.
The rear wall 2b of the card holder 2 is provided with a guide shaft 12 at right angles to the direction of holder movement. A slide member 13 is freely slidably disposed on the guide shaft 12 and is linked to the holder feed mechanism 4.
The holder feed mechanism 4 includes two vertical rotary shafts 40a, 40b freely rotatably provided on a fixed frame provided inside the case 10, pulleys 41a, 41b fixed to upper ends of the respective rotary shafts 40a, 40b, an endless belt 42 wound about the pulleys 41a, 41b, and a connecting pin 43 provided on the endless belt 42 at an appropriate location and freely rotatably connected to the slide member 13.
A pulley 45 is supported on the lower end of the rotary shaft 40b and is coupled via transmission means 44 such as a belt to an output shaft of a drive motor 46 which rotates in one direction. Attached to the lower end of the other rotary shaft 40a is an encoder 47 for detecting the amount of feed of the card holder 2.
The optical head 5 is supported on a lead screw 50 and a guide shaft 51 that are disposed orthogonal to the direction of travel of the card holder 2. The lead screw 50 is driven by a reversibly rotatable head feed motor 52. When the motor 52 is actuated, the optical head 5 is shifted by the guide shaft 51 and lead screw 50 in the direction perpendicular to the feed direction of the optical head 8, thereby accessing the information recording tracks 81.
Provided on the inner side of the card insertion slot 1 are a sensor 6 for sensing an introduced optical card 8, and the card loading/ejecting mechanism 7 actuated in response to a detection output from the sensor 6 to automatically transport the optical card 8 into and out of the card holding mechanism 20 of the card holder 2.
The card loading/ejecting mechanism 7 comprises a driving roller 70 disposed at a position above the holder travel path in the vicinity of the card insertion slot 1, and a loading auxiliary mechanism 71 disposed below the holder travel path at a position opposing the driving roller 70.
The loading auxiliary mechanism 71 comprises a driven roller 72 and a solenoid 73 for raising and lowering the driven roller 72 nd is so situated that when the driven roller 72 is raised it will pass through the rectangular window 25 in the card holder 2 and contact the driving roller 70.
The driving roller 70 is driven reversibly by a loading motor 74 so that the optical card 8 placed in the card insertion slot 1 is clamped between the roller 70 and the driven roller 72 to be introduced to the card holder 2 and then fed out to the card insertion slot 1 following processing.
In FIG. 1, numeral 29 denotes a hole formed in the retaining plate 23 in order that the driving roller 70 may project below the retaining plate 23. Numeral 25a in FIG. 6 denotes a cut-out, which communicates with the rectangular window 25, for allowing the driven roller 72 to project above the card support plate 22.
The operation of the card processing apparatus constructed as set forth above will now be described.
In a standby state prior to insertion of the optical card 8, the card holder 2 is situated in the vicinity of the card insertion slot 1 and the retaining plate 23 of the card holder 2 is in a state in which it is urged upwardly by the actuating member 30 of the release mechanism 3. Consequently, the card support plate 22 of the card holder 2 and the retaining plate 23 are spaced apart from each other, as a result of which the optical card 8 is capable of being received on the card support plate 22.
If the optical card 8 is now inserted from the card insertion slot 1 and sensed by the sensor 6, the loading motor 74 of the card loading/ejecting mechanism 7 begins operating and the driving roller 70 is rotated. In the standby state, the driven roller 72 of the loading auxiliary mechanism 71 is elevated to a position opposing the driving roller 70, so that the inserted optical card 8 is clamped between the driving roller 70 and driven roller 72 and introduced to the card holder 2. When the optical card 8 is conveyed n to a fixed position on the card support plate 22, the driven roller 72 of the loading auxiliary mechanism 71 is lowered, as shown in FIG. 5, after which the actuating member 30 of the release member 3 descends and the retaining plate 23 presses the optical card 8 against the card support plate 22 of the card holder 2 owing to the spring force of the coil spring 28 in the pressuring mechanism 24. The loading motor 74 is stopped to cease rotation of the driving roller 70.
FIG. 6 illustrates the optical card 8 in a state held on the card support plate 22 by the retaining plate 23. The information recording zone 80 of the optical card 8 is situated opposite the position of the rectangular window 25, and the four sides of the optical card 8 are held clamped between the card support plate 22 and the retaining plate 23 while in intimate contact with the front end portion 22a, rear end portion 22b and both longitudinal side portions 22c, 22d of the card support plate 22. Accordingly, even if the optical card 8 undergoes curvature, such deformation is correctd by pressure applied by the coil spring 28. Since all four sides of the optical card 8 are held, there are no free ends to vibrate.
When the optical card 8 is held on the card holder 2, the holder feed mechanism 4 begins operating in conjunction with the card holder and the endless belt 42 is caused to travel by drive supplied by the motor 46. As a result, the connecting pin 43 on the endless belt 42 pulls the card holder 2 along the guide shafts 11 via the slide member 13 to shaft the card holder 2 in a first direction (from the side of the insertion slot toward the interior of the case 10).
When the connecting pin 43 reaches the outer periphery of the pulley 41b, the pin slides the slide member 13 in the width direction of the card holder 2 and the pulley 41b makes a half revolution to shift the slide member in a second direction opposite the first direction mentioned above (namely toward the insertion slot 1). Thereafter, through an operation similar to that involving the first direction, the connecting pin 43 shifts the guide holder 2 in the second direction along the guide shafts 11 via the slide member 13. Thus, the card holder 2 is reciprocated by continuous rotation of the drive motor 46 in one direction.
When the holder 2 is moved in the second direction, the optical head 5 moves relative to the information recording track 81 of the optical card 8 to record and/or reproduce information.
When the guide holder 2 beings to return to the initial position, the head feed motor 52 is actuated and the optical head 5 accesses the tracks on the optical card 8 while traveling along the guide shaft 51 and lead screw 50, after which the same card feeding operation is repeated.
Though the foregoing embodiment is so adapted that all four sides of the optical card 8 are held in a pressed state, an arrangement can be adopted in which three sides of the optical card 8 are held in a pressed state.
In the present embodiment, the optical card 8 is introduced and extracted by the loading/ejecting mechanism 7 while inclined with respect to the card holder 2. In other words, when the optical card 8 is introduced to the card holder 2 and when it is ejected from the card holder 2, the information recording zone 80 of the optical card 8 does not contact the front edge portion 22a and rear edge portion 22b (and of course, the two side portions 22c, 22d) of the card support plate 22. Accordingly, damage to the information recording zone 80 of the optical card 8 owing to contact between the zone and any mechanical member can be prevented before it occurs.
As many apparently widely different embodiments of the present invention can be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims. | An optical card processing apparatus includes a holder feed mechanism (4) for reciprocating a card holder (2) holding an optical card (8), an optical head (5) for recording information on and/or reproducing information from the optical card held by the card holder, and a card holding mechanism provided on the card holder for pressingly holding at least three sides of the optical card. Deformation of the optical card can be corrected and vibration thereof suppressed by the card holding mechanism. As a result, focal-point error due to card curvature and vibration is reduced and optical cards can be fed at a higher speed. | 6 |
BACKGROUND
This application relates to a retention feature for retaining a thrust washer against rotation in a planetary gear system.
Planetary gear systems are well known, and have been utilized to provide a gear change between an input and an output. A sun gear rotates about a central axis, and a ring gear rotates about the same center but outwardly of the sun gear. A plurality of planet gears are positioned to transmit rotation from the sun gear to the ring gear.
In one known type of planetary gear system, the planet gears are mounted on stationary shafts positioned inwardly of the ring gears. The planet shaft provides an inner race for bearings which support the planet gears. Also, thrust washers sit at both ends of the planet shaft, and provide axial thrust surfaces against the end surfaces of the planet gears.
One application of a planetary gear system is in an air turbine starter system. In an air turbine starter system, air is delivered across a turbine rotor to drive the rotor. The rotor drives a sun gear, which drives a ring gear through planet gears. The ring gear in turn drives a starter output shaft for a gas turbine engine.
In such applications, the asymmetry and clearances of the planet gears tend to induce an axial force, which reacts against the thrust washers. Those reacted gear forces attempt to rotate the thrust washers, which must remain stationary relative to the fixed housing. The thrust washers serve to provide a designated durable surface for that relative motion and loading. In the prior art, the thrust washers received a simple pin to limit rotation.
SUMMARY
A bushing for use in a planetary gear system has a cylindrical body portion defining a bore extending along a central axis to be received on a planetary gear shaft. A tab extends axially beyond a nominal body portion of the bushing and is received in a notch in a thrust washer adjacent to the bushing to prevent rotation of the thrust washer.
A gear cage and an air turbine starter incorporating the bushing, along with a method of installing the bushing are also disclosed and claimed.
These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an air turbine starter assembly.
FIG. 2 shows a portion of a gear cage.
FIG. 3A shows a perspective view of a flanged bushing.
FIG. 3B is a cross-sectional view through the flanged bushing of FIG. 3A .
FIG. 3C is an end view of the flanged bushing of 3 A.
FIG. 4A shows a thrust washer.
FIG. 4B is a cross-sectional view of the FIG. 4A thrust washer.
FIG. 5A is a cross-sectional view through a second bushing.
FIG. 5B is an end view of the sleeve.
FIG. 6A shows another thrust washer.
FIG. 6B is a cross-sectional view of the FIG. 6A thrust washer.
FIG. 7A shows yet another thrust washer.
FIG. 7B is a cross-sectional view of the FIG. 7A thrust washer.
DETAILED DESCRIPTION
An air turbine starter assembly 20 may be associated with an aircraft, or other systems including a gas turbine engine as shown in FIG. 1 . A source of hot air 22 , which may be from an auxiliary power unit, as typically utilized while on the ground, delivers hot, high pressure air into an inlet 24 . The high pressure air flows across a turbine rotor 26 , causing the turbine rotor 26 to rotate. As the turbine rotor 26 rotates, it rotates an output shaft 28 through a planetary gear system. The output shaft 28 may be utilized as a starter, to initiate operation of a main gas turbine engine 30 .
The planetary gear system includes a sun gear 34 that is driven by a rotor shaft 32 that rotates with the turbine rotor 26 . The sun gear 34 in turn drives a plurality of planet gears 40 . The planet gears 40 include output gear teeth 41 , which drive a ring gear 42 . The ring gear 42 drives the output shaft 28 through a mechanical clutch connection.
The planet gears 40 rotate about a stationary planet shaft 44 . The stationary planet shaft 44 includes an end flange 46 that is fixed to prevent rotation relative to a housing 38 . Needle bearings 300 support the gear 40 on stationary shaft 44 .
As shown in FIG. 2 , a thrust washer 100 sits on one end face of the planet gear 40 , and the combined pair of thrust washers 134 and 136 sit on an opposed end. A bushing 102 includes a nominal body portion press-fit into the housing bore, and has a protruding axial tab 106 at one end extending into a notch 108 in the thrust washer 100 . The tab 106 prevents rotation of the thrust washer 100 . A flange 112 is formed at an outboard end of the bushing 102 , and serves to position the bushing against the counterbore surface 116 in the housing 38 .
FIG. 3A shows a detail of the bushing 102 , including the flange 112 and tab 106 .
The bushing 102 is shown in cross-section in FIG. 3B . A nominal body portion 111 is the portion which is force-fit into a housing bore. The flange 112 is also illustrated. The tab 106 extends axially from the nominal body portion 111 . As shown, the nominal body portion 111 extends for an axial length d 0 , while the tab extends for an axial length d 1 . The tab 106 has an inner curved surface positioned from a center axis by a radius R 1 . The outer periphery of tab 106 is defined by R 3 . The outer periphery of body 111 is defined by D 1 which is the surface contacting the housing bore.
As shown in FIG. 3C , the bushing 102 has the tab 106 extending over a circumferential width d 2 . The d 2 dimension is a side-to-side dimension, generally extending circumferentially. In the embodiment shown, the sides are generally parallel to each other, and the distance would thus be measured between the parallel sides. An alternate embodiment could have those surfaces radiating from center, for which d 2 would be an arc length or an angular dimension.
FIG. 4A shows the thrust washer 100 having oil grooves 118 on one face, and a notch 108 . A countersunk bore 114 can also be seen in FIG. 4B . As shown, the notch 108 extends for a circumferential width d 3 . As also shown in FIG. 4B , the inner most bore of the washer 100 (that length not including the countersunk bore 114 ) extends for an axial dimension d 4 .
In one embodiment, d 0 was 0.386″ (0.980 cm); d 1 was 0.100″ (0.254 cm); d 2 was 0.125″ (0.317 cm); d 3 was 0.196″ (0.498 cm); and d 4 was 0.108″ (0.274 cm). In that same embodiment, D 1 was 0.766″ (1.94 cm), and R 1 was 0.303″ (0.770 cm), and R 3 was 0.373″ (0.947 cm).
In embodiments, a ratio of d 1 to d 0 is between 0.2 and 1.0; a ratio of d 2 to d 3 is between 0.60 and 0.98; and a ratio of d 1 to d 4 is between 0.20 and 0.98.
Returning to FIG. 2 , at an opposed end of the planet gear 40 , is a flangeless bushing 130 , which is also press-fit into the gear cage housing bore, and positioned by bottoming on the bushing end face 160 . Bushing 130 also has a tab or an extension 132 extending inboard, which engages into the notch 142 in thrust washer 136 and into notch 140 in thrust washer 134 . Thrust washers 134 and 136 function together as a spherical joint, in which thrust washer 134 nests into thrust washer 136 . Thrust washer 136 has a notch 142 extending through its entire axial length, while thrust washer 134 has notch 140 extending a finite axial distance. The tab 132 of the bushing 130 extends within the notches 140 and 142 in the washers 134 and 136 to prevent rotation of those washers.
FIG. 5A shows the bushing 130 . Tab 132 extends from the nominal body portion 146 . As shown, the outer periphery of the nominal body portion 146 is at a diameter D 3 . The inner curved surface of the tab 132 is at a radius R 2 . The tab 132 extends for an axial distance of d 5 , while the nominal body portion 146 extends for an axial dimension of d 6 .
FIG. 5B is an end view of the bushing 130 , and shows the tab 132 . Tab 132 extends for a side-to-side dimension d 7 , measured circumferentially. In the embodiment shown, the sides are generally parallel to each other, and the distance would thus be measured between the parallel sides. An alternate embodiment could have those surfaces radiating from center, for which d 2 would be an arc length or an angular dimension.
The washer 136 is illustrated in FIG. 6A . As can be seen between FIGS. 6A and 6B , a concave face 158 is formed on one side, and spaced from a perpendicular face 156 . A notch 142 extends through the entire axial thickness of the washer 136 . As shown in FIG. 6A , the width of the notch 142 is defined as d 8 .
FIG. 6B shows the washer 136 has the notch 142 extending for an axial length d 9 .
FIG. 7A shows the washer 134 . Washer 134 has a notch 140 with a width d 10 . Also, oil grooves 301 can be seen.
FIG. 7B shows the mating thrust washer 134 . Washers 134 and 136 nest together, as mentioned above. Washer 134 has a notch 140 extending to an end surface 138 , with a depth d 11 . A convex face 150 is spaced from a relatively perpendicular face 152 .
In one embodiment, d 5 was 0.191″ (0.485 cm); d 6 was 0.413″ (1.04 cm); d 7 was 0.125″ (0.317 cm); d 8 was 0.196″ (0.498 cm); d 9 was 0.070″ (0.178 cm); d 10 was 0.196″ (0.498 cm); and d 11 was 0.140″ (0.356 cm). In that same embodiment, D 3 was 0.746″ (1.90 cm) and R 2 was 0.323″ (0.820 cm). In embodiments, a ratio of d 5 to d 6 is between 0.20 and 1.0; a ratio of d 7 to d 8 is between 0.60 and 0.98; and a ratio of d 5 to the sum of d 9 and d 11 was between 0.2 and 0.98.
Both distances d 2 and d 7 could be defined as side-to-side distances measured circumferentially about an axis. Of course, the sides are generally parallel to each other, and the distance would thus be measured between the parallel sides. An alternate embodiment could have those surfaces radiating from center, for which d 2 would be an arc length or an angular dimension.
The tabs and grooves are sized such that there is a small clearance between the outer periphery of the tab and the inner periphery of the groove. Still, the tabs will prevent relative rotation of the grooves, and their respective component features.
This assembly provides a secure way of preventing rotation of the washers 134 , 136 and 100 , without requiring extra components.
This method of assembly and rotation restriction provides increased contact area between the tab sides and slot edges, thereby reducing the unit load per area. This notably reduces the contact stresses, and improves wear life of the mating parts.
The disclosed combinations will increase the life of the assembly by increasing a contact area, thereby reducing stress and wear. The assembly of the embodiments is improved by reducing part count, thereby reducing inventory and related costs. In addition, there are reduced assembly operations and labor, and an ease of assembly benefits. As an example, the disclosed combinations eliminate blind assembly, such as inserting narrow pins into a blind hole.
Although an embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention. | A bushing for use in a planetary gear system has a cylindrical body portion defining a bore extending along a central axis to be received on a planetary gear shaft. A tab extends axially beyond a nominal body portion of the bushing and is received in a notch in a thrust washer adjacent to the bushing to prevent rotation of the thrust washer. A gear cage and an air turbine starter incorporating the bushing, along with a method of installing the bushing are also disclosed. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention:
The present invention relates to a constant-velocity driving arrangement for a camera shutter of the type in which a sector is driven by a motor.
2. Description of the Prior Art:
Camera shutters capable of performing many various exposure modes by driving a sector with a motor are put to practical use. Since a battery is used as a motor driving power supply, the speed of travel of the sector tends to change due to variations in the battery voltage, resulting in errors in the amount of exposure.
Shutter devices of the type in which a sector is driven by a motor are widely used in camera electronically controlled. Such a shutter device can perform many various exposure modes, but is problematic in that the exposure accuracy is poor since the rotational speed of the motor depends on the voltage of a battery which is a source of drive energy for the shutter device. To solve the above problem, it has been customary to provide a higher battery voltage setting than the rated voltage of the motor, and to supply a constant voltage to the motor through a constant-voltage circuit that utilizes the conduction resistance of a transistor. However, when the voltage of the battery is high, the drive voltage is lowered by the constant-voltage circuit, and hence the battery power is consumed as Joule heat resulting in a shortened battery service life, and an excessive margin is required for the power supply voltage.
SUMMARY OF THE INVENTION
In view of the aforesaid problems of the conventional shutter devices, it is an object of the present invention to provide a shutter control circuit capable of supply a shutter driving motor with pulsed electric power and capable of varying the duty cycle of the pulsed power according to the rotational speed of the motor for more efficient utilization of the battery power to drive the motor at a constant speed.
According to the present invention, there is provided a device for controlling the rotational speed of a shutter driving motor for a camera, including means for detecting the rotational speed of the motor which drives a sector, and means for varying the duty cycle of the motor according to the detected rotational speed.
In view of the aforesaid problems of the conventional camera shutters, it is another object of the present invention to provide a shutter control device for cameras which is capable of effecting fine adjustment of a shutter aperture closing time according to the time measured after operation of the motor to open a shutter until the shutter starts to be opened, so that a correct amount of exposure can be obtained irrespective of the voltage of a battery.
According to the present invention, there is provided a device for controlling a camera shutter comprising means for detecting a time interval after a shutter driving motor has started to rotate until a sector is opened, correcting means for correcting an amount of exposure based on the detected time interval, and means for determining a shutter aperture closing time according to a signal from the correcting means.
The above and other objects, features and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which preferred embodiments of the present invention are shown by way of illustrative example.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a shutter control device according to the present invention;
FIG. 2 is a waveform diagram showing operation of the shutter control device;
FIG. 3 is a block diagram of a shutter control device according to another embodiment of the present invention;
FIG. 4 is a plane view of a shutter mechanism to which the present invention is applied;
FIG. 5 is a block diagram of a speed control device according to another embodiment of the present invention;
FIG. 6 is a waveform diagram showing operation of the speed control device; and
FIG. 7 is a plane view of a shutter mechanism to which the present invention is applied.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 4 shows a shutter mechanism to which the present invention is applied. The shutter mechanism includes a drive plate 1 movably mounted by pins on a fixed base plate (not shown) through slots 1a, 1b formed in the drive plate 1. The drive plate 1 has a rack 1c meshing with a pinion 2 for receiving a driving force from rotary means in the form of a drive motor 3, and a projection 1d for closing a switch 10 which selects, at a time, one of a focusing mode and an exposure mode. The drive plate 1 also has a cam grove 1e for rendering a sector 4 to turn through a non-operative region without opening the aperture in the focusing mode and for turning the sector 4 through an operative region dependent on the interval of travel of the drive plate 1 to carry out the exposure operation, the cam groove 1e being composed of a horizontal portion extending in the direction in which the drive plate 1 is movable and an oblique portion contiguous to the horizontal portion. The sector 4 covers an aperture opening 8 and is operatively coupled to a sector lever 5 which support on the arm end thereof a pin 5a inserted in the cam groove 1e. The sector 4 may be plural.
A shutter closing lever 6 is angularly movably mounted on the fixed base plate by means of a shaft 6a and is normally urged by a spring 6b to turn counterclockwise about the shaft 6a. The shutter closing lever 6 has a projection 6c disposed on one lower side thereof and facing the selector lever 5. An attractable member 6d is mounted on the other lower side of the shutter closing lever 6 and is attractable by an electromagnet 7 that is swingably mounted on the fixed base plate through a spring 7a. When the drive plate 1 is in a home position, an upper portion of the shutter closing lever 6 is turned clockwise by a pin 1f on the drive plate 1 to allow the attractable member 6d to be attracted to the electromagnet 7. When the electromagnet 7 is de-energized, the shutter closing lever 6 is turned counterclockwise under the resiliency of the spring 6b to cause the projection 6c to actuate the sector lever 5 counterclockwise, thereby closing the sector 4.
The sector 4 has a through hole 4a defined in one end thereof. The hole 4a is positioned such that when the sector 4 is stopped in its closed position, the hole 4a registers with a light detector 16a for measuring the brightness of an object to be photographed. The sector 4 also has a recess 4b which registers with the light detector 16a when a shutter aperture starts to be formed. A rangefinder device includes a scanning member 9 which is angularly movable by a slanted surface on an upper edge of the drive plate 1.
FIG. 1 shows a shutter control device according to the present invention. The shutter control device has a circuit 11 for measuring a sector opening time, the circuit 11 including an AND gate 11a receptive of a shutter opening signal, a clock signal CK2, and a signal from a photometric circuit 16, and a counter 11b for counting the clock signal CK2 fed from the AND gate 11a. The circuit 11 operates to detect a time ΔT required for the recess 4b of the sector 4 to move to a position registering with the light detector 16a after a the shutter opening signal has been issued to initiate the sector 4 to open the aperture. A corrective amount determining circuit 12 selects one frequency fm out of a plurality of frequencies f1, f2, . . . fs . . . fn supplied from a frequency-divider circuit 13 based on the time ΔT, and supplies the selected frequency fm as a clock signal to a shutter aperture closing control circuit 20. An exposure calculating circuit 18 calculates an amount of exposure EX based on film sensitivity data from a film sensitivity detecting circuit 14 and object brightness data from the photometric circuit 16, and provides an access signal to an exposure data memory circuit 19 based on the calculated exposure amount EX. The exposure data memory circuit 19 has exposure amounts EX1, EX2, . . . EXn as addresses and stores, as data, shutter closing times D1, D2, . . . Dn (see Table 1 below) corresponding to the exposure amounts, respectively.
TABLE 1______________________________________Address EX1 EX2 EX3 . . . . . . EXn______________________________________Data D1 D2 D3 Dn______________________________________
A shutter aperture closing control circuit 20 includes an AND gate 20a which is opened to pass clock having frequency fm from the corrective amount determining circuit 12 in response to a signal issued from the light detector 16a upon completion of a photometric process, a presettable counter 20b for setting a shutter closing time from the exposure data memory circuit 19, and an electromagnet control circut 20c for de-energizing the electromagnet 7 in response to counting-up of the presettable counter 20b.
An ISO converter circuit 15 converts the film sensitivity into an ISO value. An analog-to-digital converter 17 converts a photometric signal into a corresponding digital signal. A clock pulse generator 21 generates clock pulses applied to the frequency-divider circuit 13. A motor control circuit 23 drives the motor 3 in response to a shutter opening signal from a switch control circuit 22.
Operation of the device thus constructed will be described with reference to the timing diagram of FIG. 2.
When the shutter release button is depressed to a first stage, the brightness of the object is detected by the light detector 16a through the hole 4a of the sector 4, whereupon the exposure calculating circuit 18 calculates an amount of exposure EX suitable for photographing the object based on the film sensitivity data and brightness data. A shutter closing time Da corresponding to the calculated exposure amount EX is read out from the exposure data memory circuit 19 and is preset in the shutter aperture closing control circuit 20. Upon further depression of the shutter release button to a next stage, the switch control circuit 22 issues a shutter opening command signal to rotate the motor 3 and energize the electromagnet 7 to attract the drive plate 1. In response to the shutter opening signal, the gate 11a of the sector opening time measuring circuit 11 is opened to enable the counter 11b to start counting the clock signal CK2. The motor 3 rotates at a rotational speed dependent on the voltage of a battery (not shown) for turning the sector 4 from its home position to an opening position. When the sector 4 starts to open and the recess 4b is brought in registration with the light detector 16a during the above turning movement, light is again insoliated on the light detector 16a, causing a level change of the output signal from the photometric circuit 16. In response to this level change, the sector opening time measuring circuit 11 closes the gate 11a to shut off the clock signal CK2 applied to the counter 11b. The number of clock pulses counted by the sector opening time measuring circuit 11 represents the rotational speed of the motor 3. The corrective amount determining circuit 12 selects a clock signal fm of a high frequency when the measured opening time ΔT, i.e., the time required until the aperture is opened, is short, and selects a clock signal fm of a low frequency when the time ΔT required until the aperture is opened, is long. Namely, the selected frequency fm is inversely proportional to the measured opening time ΔT. The corrective amount determining circuit 12 applies the selected clock signal fm to the shutter closing control circuit 20. The time required for the shutter closing control circuit 20 to reach counting-up the stored data Da is reduced in inverse proportion to the selected frequency fm, and, as a result, the time when the sector 4 is closed is extended or delayed in proportion to the time ΔT.
At a time Db when the product of the amount of opening and the opening time (indicated by an area Sb) is equal to the amount of exposure determined by the exposure calculating circuit 18 (indicated by an area Sa), the shutter aperture closing control circuit 20 reaches its counting-up, thereby de-energizing the electromagnet 7 to close the sector 4. Thus, a shortage of the opening of the aperture due to a drop of the battery voltage is compensated for by increasing the time internal during which the sector is opened.
FIG. 3 shows a second embodiment of the present invention. A corrective amount determining circuit 30 is responsive to a signal from the shutter opening time measuring circuit 11 for converting this signal into an exposure amount ΔEX, which is applied to a correction calculating circuit 31. The correction calculating circuit 31 adds a corrective exposure amount ΔEX to the exposure amount EX from the exposure calculating circuit 18, and an access signal to the exposure data memory circuit 19 based on the sum.
When the shutter release button is depressed to a first stage, the brightness of the object is detected by the light detector 16a through the hole 4a of the sector 4, whereupon the exposure calculating circuit 18 calculates an amount of exposure EX suitable for photographing the object based on the film sensitivity data and brightness data. Upon further depression of the shutter release button to a next stage, the switch control circuit 22 issues a shutter opening command signal to rotate the motor 3 and energize the electromagnet 7 to attract the drive plate 1. In response to the shutter opening signal, the gate 11a of the sector opening time measuring circuit 11 is opened to enable the counter 11b to start counting the clock signal CK2. The motor 3 rotates at a rotational speed dependent on the voltage of a battery (not shown) for turning the sector 4 from its home position to an opening position. When the sector 4 starts to open and the recess 4b is brought into registration with the light detector 16a during the above turning movement, light is again passed to the light detector 16a, causing the level change in the output signal from the photometric circuit 16. In response to this level change, the sector opening time measuring circuit 11 closes the gate 11a to complete the measurement of the opening time ΔT. Based on the measured time ΔT, the corrective amount determining circuit 30 supplies a signal representative of a corrective exposure amount ΔEX to the correction calculating circuit 31, which adds the exposure amount EX to the corrective exposure amount ΔEX to obtain a corrected exposure amount EX'=EX+ΔEX. The correction calculating circuit 31 then specifies a shutter closing time Db corresponding to the corrected exposure amount EX' in the exposure data memory circuit 19, and sets the shutter closing time Db in the counter 20b of the shutter aperture closing control circuit 20. At the same time, the counter 20b starts counting a clock signal CK3 of a constant frequency. Even when a shutter aperture closing time Da corresponding to the exposure amount EX calculated by the exposure calculating circuit 18 is reached as the motor 3 further rotates, the shutter aperture closing control circuit 20 cannot issue a counting-up signal since the time Db corresponding to the corrected exposure amount EX'=EX+ΔEX is preset therein. Therefore, at a time when the product of the amount of opening and the opening time (indicated by the area Sb in FIG. 2) is equal to the amount of exposure determined by the exposure calculating circuit 18 (indicated by the area Sa in FIG. 2) as a result of further rotation of the motor 3 for a time corresponding to the time ΔT required until the aperture is opened, the shutter aperture closing control circuit 20 reaches its counting-up, closing the sector 4. Thus, a reduction in the opening of the aperture due to a drop of size the battery voltage is compensated for by increasing the time interval during which the sector is kept open.
In the illustrated embodiment, the aperture is closed by actuating the sector lever 6 in response to de-energization of the electromagnet. However, the present invention is also applicable to a shutter device of the type in which the motor is reversed to close the aperture.
While the time when the sector starts to open the aperture is detected by the photometric light detector in the above embodiments, such time may be detected by any of various other detectors such as a limit switch.
With the arrangement of the present invention, the time interval after the start operation of the motor to open the shutter until the sector starts to form the aperture is measured, and the timing to issue a shutter aperture closing control signal is adjusted according to the measured time interval. Therefore, accurate exposure can be obtained irrespective of changes in the battery voltage, and the battery energy can be effectively utilized until the end of its service life.
Although certain preferred embodiments have been shown and described, it should be understood that many changes and modifications may be made therein without departing from the scope of the appended claim.
FIG. 7 shows a shutter mechanism in which a third embodiment of the present invention is applied. The shutter mechanism includes a drive plate 1 movably mounted by pins on a fixed base plate (not shown) through slots 1a, 1b formed in the drive plate 1. The drive plate 1 has a rack 1c meshing with a pinion 2 for receiving a driving force from a drive motor 3, and a projection 1d for closing a switch 10 which selects, at a time, one of a focusing mode and an exposure mode. The drive plate 1 also has a cam grove 1e for rendering a sector 4 inoperative in the focusing mode and for turning the sector 4 dependent on the interval of travel of the drive plate 1 in the exposure mode, the cam grove 1e being composed of a horizontal portion extending in the direction in which the drive plate 1 is movable and an oblique portion contiguous to the horizontal portion. The sector 4 covers an aperture opening 8 and is operatively coupled to a sector lever 5 which supports on the arm end thereof a pin 5a inserted in the cam groove 1e. The sector 4 may be plural.
A shutter closing lever 6 is angularly movably mounted on the fixed base plate by means of a shaft 6a and is normally urged by a spring 6b to turn counterclockwise about the shaft 6a. The shutter closing lever 6 has a projection 6c disposed on one lower side thereof and facing the sector lever 5. An attractable member 6d is mounted on the other lower side of the shutter closing lever 6 and is attractable by an electromagnet 7 that is swingably mounted on the fixed base plate through a spring 7a. When the drive plate 1 is in a home position, an upper portion of the shutter closing lever 6 is turned clockwise by a pin 1f on the drive plate 1 to allow the attractable member 6d to be attracted to the electromagnet 7. When the electromagnet 7 is de-energized, the shutter closing lever 6 is turned counterclockwise under the resiliency of the spring 6b to cause the projection 6c to actuate the sector lever 5 counterclockwise, thereby closing the sector 4.
The sector 4 has a groove 4a formed in one end thereof, the groove 4a having a length l. The groove 4a is positioned such that when the sector 4 is stopped in its closed position, the groove 4a registers with a light detector 16a for measuring the brightness of an object to be photographed. A rangefinder device includes a scanning member 9 which is angularly movable by a slanted surface on an upper edge of the drive plate 1.
FIG. 5 shows a shutter control device according to the present invention. The shutter control device has a circuit 11 for detecting the rotational speed of the motor, the circuit 11 including an AND gate 11a receptive of a shutter driving signal, a clock signal, and a signal from a photometric circuit 16, and a counter 11b for counting the clock signal issued from the AND gate 11a. The circuit 11 operates to detect a time t rquired for the sector 4 to be displaced through the distance l which corresponds to the length of the groove 4a. A driving duty cycle determining circuit 40 selects a preset basic duty cycle signal when a shutter opening command is issued from a switch control 22, and determines a driving duty cycle and issues the same to a motor control circuit 23 in response to a signal from the motor speed detecting circuit 11. An exposure calculating circuit 18 calculates an amount of exposure based on film sensitivity data from a film sensitivity detecting circuit 14 and object brightness data from the photometric circuit 16, and provides an access signal to an exposure data memory circuit 19. The exposure data memory circuit 20 has exposure amounts EX1, EX2, . . . EXn as addresses and stores, as data, shutter closing timings D1, D2, . . . Dn (see Table 1 below) corresponding to the exposure amounts, respectively.
TABLE 1______________________________________Address EX1 EX2 EX3 . . . . . . EXn______________________________________Data D1 D2 D3 Dn______________________________________
A shutter aperture closing control circuit 20 includes an AND gate 20a which is opened to pass clock pulses CK3 in response to the shutter opening command signal from the switch control circuit 22 upon depression of a shutter release button, a presettable counter 20b for setting the selected shutter closing time data from the exposure data memory circuit 19, and an electromagnet control circuit 20c for de-energizing the electromagnet 7 in response to a counting-up signal from the presettable counter 20b.
A frequency-divider circuit 13 generates motor driving basic frequency signals f1,f2, . . . fn for deciding the duty of the motor driving signal, and clock signals CK1, CK2, CK3 for use in the respective countors. An ISO converter circuit 15 converts the film sensitivity data from the circuit 14 into an ISO value, and an analog-to-digital converter 18 converts a photometric signal into a corresponding digital signal. A clock pulse generator 21 generates clock pulses applied to the frequency-divider circuit 13 in response to oscillation of a crystal resonator.
Operation of the device thus constructed will be described with reference to the waveform diagram of FIG. 6.
When the shutter release button is depressed to a first stage, the brightness of the object is detected by the light detector 16a through the groove 4a of the sector 4, whereupon the exposure calculating circuit 18 calculates an amount of exposure suitable for photographing the object based on the film sensitivity data and brightness data. Upon further depression of the shutter release button, the switch control circuit 22 issues a shutter opening command signal effective to enable the driving duty cycle determining circuit 40 issue a basic duty cycle signal for starting the motor 3 to rotate and effective to energize the electromagnet 7 to attract the drive plate 1. At the same time, the gate 11a of the motor speed detecting circuit 11 is opened to enable the counter 11b to count the clock signal CK2. As the sector 4 starts to turn for the distance l corresponding to the length of the groove 4a, the light that has been applied to the light detector 16a is now shut off by the sector 4, whereupon the gate 11a is closed, cutting off the clock signal CK2 applied to the counter 11b. The count of the counter 11b, which indicates the counted number of clock pulses, is representative of the time required for the sector 4 to move the distance l with driving electric power of a basic duty cycle, i.e., representative of the rotational speed of the motor 3 depending on the battery voltage. The driving duty cycle determining circuit 40 calculates a driving duty cycle based on the count of the counter 11b, i.e., the rotational speed of the motor 3, and enables the motor control circuit 23 to regulate the driving electric power supplied to the motor 3.
More specifically, when the rotational speed of the motor at the basic duty cycle is low, the output voltage from the battery is low. Therefore, the time ΔT in which the motor 3 is energized per cycle T is increased to increase the average driving voltage applied to the motor 3. When the rotational speed of the motor is high, the energization time ΔT is reduced to lower the average driving time. During a non-energization period T-ΔT, no electric power is consumed since the current from the battery is cut off.
The motor 3 is therefore rotated at a normal speed under a constant average driving voltage irrespective of variations in the voltage of the battery, thereby allowing an exposure to be carried out according to the brightness of the object. At the time an aperture corresponding to the amount of exposure is formed, the shutter aperture closing control circuit 20 undergoes counting-up, thereby de-energizing the electromagnet to close the shutter.
In the illustrated embodiment, the aperture is closed by actuating the sector lever in response to de-energization of the electromagnet. However, the present invention is also applicable to a shutter device of the type in which the motor is reversed to close the aperture.
While the rotational speed of the motor is detected by the photometric light detector in the above embodiment, a separate speed detecting means or a number of rotation detecting means may be disposed on any of the members ranging from the motor shaft to the sector for detecting the rotational speed or numbers of the motor rotation.
With the arrangement of the present invention, the rotational speed of the motor is detected during an initial period of opening movement of the shutter, and the driving voltage for the motor is controlled on the basis of the detected rotational speed. Therefore, the shutter can be driven at a constant speed for accurate control of an amount of exposure irrespective of variations in the battery voltage. Inasmuch as the motor driving voltage is controlled by the time duration of energization, the rotational speed of the motor can be adjusted without a wasteful consumption of the electric power, and no excessive margin is necessary for the power supply voltage.
Although certain preferred embodiments have been shown and described, it should be understood that many changes and modifications may be made therein without departing from the scope of the appended claims. | A camera has a shutter device driveable to undergo opening movement to open an aperture to effect exposure operation according to a given exposure value, and a motor actuatable to rotate at an unstable rotational speed for driving the shutter device. A detector operates after the motor starts rotating and before the shutter device undergoes its opening movement for detecting the rotational speed of the motor. A controller adjusts the shutter device in accordance with the detected rotational speed of the motor to thereby enable the shutter device to effect the exposure operation so as to accurately achieve the given exposure value. | 6 |
TECHNICAL FIELD
The invention relates to vacuum processing substrates, including microelectronic or optical components, and to temperature control of such substrates in evacuated environments.
BACKGROUND
Vacuum processing operations on substrates, such as deposition of thin films, often require control over substrate temperature. Deposition operations include sputtering, evaporation, and chemical vapor deposition. Related operations such as cleaning, planarizing, annealing, and etching can also require substrate temperature controls.
Some operations require the addition of heat, and others require excess heat to be removed. Also, certain combinations of operations require both heating and cooling in various orders. Heating can be accomplished with radiant heaters that focus heat energy on substrate surfaces. Cooling is often accomplished by removing the substrates from the evacuated environment. However, with these limited controls, constant substrate temperatures are difficult to maintain and temperature transitions can be time consuming.
Better control over substrate temperature has been achieved by transferring heat through substrate supports or chucks. Ordinarily, conduction in a vacuum environment between the substrate and its support is highly inefficient. However, more efficient transfers of heat are possible by filling gaps between the substrate and its support with a gas that is compatible with the vacuum processing environment.
For example, U.S. Pat. No. 4,909,314 to Lamont, Jr. discloses a substrate support that also functions as a temperature conditioner such as a heating unit or a cooling unit. The substrate is clamped to the support, and a cavity between the substrate and the support is filled with a gas such as argon. The gas, which is maintained at a pressure above that of the vacuum processing environment but well below atmospheric pressure, transfers heat by convection between the substrate and substrate support.
U.S. Pat. No. 4,949,783 to Lakios et al. discloses a similar substrate support arranged as a cooling unit. However, instead of merely conducting gas into a cavity between the substrate and its support, the gas is circulated into and out of the cavity to carry away excess heat. The cooling unit has additional areas exposed to the circulating gas to extract the heat from the gas.
Although the known substrate supports can be arranged to operate effectively as either heating units or cooling units, some combinations of vacuum processing operations require both heating and cooling to achieve desired temperature patterns. Substrate supports arranged for heating are slow to cool, and substrate supports arranged for cooling provide no means for heating. Thus, controlled variations in substrate temperatures are limited to either increases or decreases in temperature, and constant substrate temperatures are difficult to maintain in processing environments that also involve transfers of heat.
SUMMARY OF INVENTION
Our invention provides improved temperature control over substrates processed in evacuated environments. Substrate temperatures can be maintained more accurately to improve processing quality, and temperature changes can be made more rapidly to shorten processing times.
One example includes the known features of a first temperature conditioner that supports a substrate in an evacuated environment, a first cavity between the first temperature conditioner and the substrate, and a first delivery system that conducts a fluid to the cavity for exchanging heat between the first temperature conditioner and the substrate. However, our invention also includes a second temperature conditioner, a second cavity located between the two conditioners, and a second delivery system that conducts fluid to the second cavity for facilitating exchanges of heat between the two conditioners.
A control system regulates flows of fluid into and out of the second cavity to regulate the heat exchanges between conditioners. The heat exchanges are facilitated by the presence of fluid in the second cavity and inhibited by the absence of the fluid. Preferably, the first temperature conditioner is a heating unit and the second temperature conditioner is a cooling unit.
The temperature of the substrate is raised by increasing an amount of heat produced by the heating unit and by evacuating a fluid from the second cavity. The temperature of the substrate is lowered by reducing the amount of heat produced by the heating unit and by conducting the fluid to the second cavity. The cooling unit, which requires no special controls, extracts excess heat from the heating unit through the fluid in the second cavity. This significantly reduces the amount of time required to lower substrate temperature and permits the substrate to remain within the same evacuated environment for more continuous processing. The control system can also make smaller changes in fluid pressure in the second cavity, even while heating, to more closely control the substrate temperature.
The first cavity is located within the evacuated environment, but the second cavity is isolated from that environment by the first temperature conditioner. Thus, the delivery of fluid to the first cavity is required to support efficient thermal exchanges between the first temperature conditioner and the substrate, but close contact alone could have been used to provide efficient heat exchanges between the first and second temperature conditioners. Instead, our invention provides for separating the two conditioners by an independently evacuatable space (i.e., the second cavity) to inhibit as well as facilitate the heat exchanges by varying the fluid pressure.
DRAWINGS
FIG. 1 is a schematic layout in side cross section of a sputter deposition system including our new temperature controlled chuck.
FIG. 2 is a more detailed side cross-sectional view of the temperature controlled chuck.
FIG. 3 is an enlarged fragmentary view of a portion of FIG. 2 showing a seal between two temperature conditioners.
FIG. 4 is a more detailed bottom view of a two-zone heating unit that can be used as one of the temperature conditioners.
DETAILED DESCRIPTION
A sputter deposition system 10 incorporating our invention is depicted in FIG. 1. The system 10 includes the usual features of a vacuum chamber 12, which is evacuated by a pump 14, and a target 16 of material to be deposited on a wafer substrate 18. An electrical potential is applied to the target 16 in the presence of an ionizable gas, causing gas ions to strike the target 16 and release atoms of the target material into a plasma that deposits the target material on the wafer substrate 18.
The plasma can be controlled by magnets (not shown) located in the vicinity of the target 16 or the wafer substrate 18. For example, coassigned U.S. Pat. No. 5,248,402 discloses an apple-shaped magnetron mounted in the vicinity of a target for more evenly eroding the target, and coassigned U.S. application Ser. No. 08/369,381 discloses a magnetic orienting device in the vicinity of a wafer substrate for magnetically orienting the deposited target material. Both references are hereby incorporated by reference. Further details of sputtering systems are found in these references. The invention, however, is also applicable to other vacuum processing operations including evaporation, chemical vapor deposition, planarizing, annealing, etching, and cleaning.
A new substrate support, namely chuck 20, for use in such vacuum processing operations is shown also in FIG. 2 in a less schematic format. The wafer 18 mounts on an annular (peripheral) seat 22 of a heating unit 24, which is preferably made with a stainless steel body 26 (such as INCONEL) supporting a heating element 28 made of an iron-aluminum-chromium alloy (such as KANTHAL) for heating wafers up to 1000 degrees Centigrade. The annular seat 22 forms, together with the wafer 18 and the heating unit body 26, a first cavity 30. An annular (peripheral) clamp 32 secures the wafer 18 to the seat 22.
A cooling unit 34, which is preferably made with a stainless steel body 36 containing coolant passageways 38, is positioned adjacent to the heating unit 24. As best seen in FIG. 3, the stainless steel body 36 is made from two plates 36a and 36b. The passageways 38 are formed as channels in the plate 36b and are covered by the plate 36a.
An annular (peripheral) rim 42 of the heating unit 24 engages an O-ring seal 44 mounted in an annular (peripheral) seat 46 of the cooling unit 34. An annular clamp 48 urges the annular rim 42 toward the annular seat 46 for compressing the O-ring seal 44. The O-ring seal 44 is preferably made from perfluoroelastomer (such as KALREZ) to withstand elevated temperatures. The annular rim 42 is made as thin as possible to limit conduction of heat to the O-ring seal 44. On the other hand, the annular clamp 48, which is preferably made from copper, is made much thicker to conduct heat from the annular rim 42 to the cooling unit 34.
The O-ring seal 44 and annular seat 46, together with the respective bodies 26 and 36 of the heating and cooling units 24 and 34, form a second cavity 50, which is evacuatable independently of the first cavity 30 and the vacuum chamber 12. Another annular (peripheral) clamp 52 and annular (peripheral) seal 54, shown in FIGS. 1 and 2, secure the body 36 of the cooling unit 34 to a body 56 of the chuck 20. The seal 44 isolates the second cavity 50 from the evacuatable space of the vacuum chamber 12, and the seal 54 separates the vacuum chamber 12 from ambient atmospheric conditions within the chuck 20.
Separate delivery systems 60 and 70 convey fluids to the first and second cavities 30 and 50. The delivery system 60 includes a tank 62 or other source of compressed gas, such as argon, which is compatible with the processing operations within the vacuum chamber 12. A conduit 64 conveys the gas through the chuck body 56, the cooling unit body 36, and the heating unit body 26 into the first cavity 30. Along the conduit 64, a flow control valve 66 limits the flow of gas to the first cavity 30, and a vacuum gauge 68 monitors pressure in the first cavity 30.
The delivery system 70 also includes a tank 72 or other source of compressed gas. However, since the second cavity 50 is isolated from the vacuum chamber 12, a wider variety of gases can be used including gases exhibiting better convection qualities such as helium, hydrogen, and nitrogen. A conduit 74 conveys the gas through the chuck body 58 and into a fitting 80 that extends through the cooling unit body 36 into the second cavity 50. Flows from the tank 62 to the second cavity 50 are limited by flow control valve 76. A vacuum gauge 78 monitors pressure in the second cavity. In addition, a vacuum pump 84 is connected to the conduit 74 for evacuating fluid from the second cavity 50.
A control system 90 includes a processor 92 with inputs 94 and 96 from the two vacuum gauges 68 and 78 and outputs 98, 100, and 102 to the two flow control valves 66 and 76 and the vacuum pump 84 for regulating fluid pressure in the first and second cavities 30 and 50. The first cavity 30 is evacuated together with the vacuum chamber 12. A desired fluid pressure is maintained in the first cavity 50 by conducting fluid to the cavity 30 at a rate that compensates for any leakage between the annular seat 22 of the heating unit 24 and the wafer substrate 18. The vacuum pump 84 is controlled in conjunction with flow control valve 76 for regulating fluid pressure in the second cavity 50.
The heating unit 24 is controlled by lead wires 104 that extend through the fitting 80 into the second cavity 50, where they are curled in a horizontal plane to accommodate expansion and contraction of the heating element 28. Referring again to FIG. 3, the second cavity 50 has a height "H" that is at least equal to a diameter "D" of the lead wires 104 to provide the necessary space for curling the lead wires 104. Preferably, the height "H" is at least 2 millimeters.
The temperature of the wafer 18 can be approximated by monitoring the temperature of the heating unit body 26 and by calculating an approximate temperature offset of the wafer 18 based on predetermined rates of energy transfer between the heating unit 24 and the wafer 18. The wafer temperature could also be monitored directly within the vacuum chamber 12, such as by using an optical sensor (not shown) to detect levels of radiated heat.
The chuck 20 is supported on a vertical drive 108 for raising and lowering the wafer substrate 18 within the vacuum chamber. Bellows 110 seal the chuck body 56 to the vacuum chamber 12 while permitting the relative vertical movement of the chuck 20. Preferably, a plurality of bellows (not shown) provides separate exits from the vacuum chamber 12 for the conduits 64 and 74.
During both heating and cooling, the flow control valve 66 preferably maintains a predetermined pressure (e.g., 5 to 20 Torr) in the first cavity 30 sufficient to provide thermal communication between the heating unit 25 and the wafer substrate 18 and coolant is preferably circulated through the coolant passages 38 of the cooling unit 34. During heating, power is supplied to the heating unit 24 and the vacuum pump 84 evacuates fluid from the second cavity 50 to inhibit transfers of heat from the heating unit 24 to the cooling unit 34. During cooling, the power supplied to the heating unit 24 is reduced (or terminated) and the flow control valve 76 maintains fluid pressure (e.g. 10 to 50 Torr or more) in the second cavity 50 sufficient to promote transfer of heat from the heating unit 24 to the cooling unit 34.
The wafer substrate 18 can be maintained at a more stable elevated temperature by slightly overpowering the heating unit 24 (i.e., by producing excess heat) and by maintaining fluid pressure in the second cavity 50 to remove the excess heat. The wafer temperature can be slightly raised (e.g., 10 degrees Centigrade) by lowering fluid pressure in the second cavity 50 and slightly lowered (e.g., 10 degrees Centigrade) by raising the fluid pressure in the second cavity 50. This provides faster and more accurate control over wafer temperatures.
An alternative two-zone heating unit 114 is shown in FIG. 4 as it would appear when viewed from the second cavity 50. The heating unit 114 has a thermally conductive body 116 supporting inner and outer heating elements 118 and 120. The inner heating element 118 is powered through lead wires 122, and the outer heating element 120 is powered through lead wires 124. Two thermocouples 126 and 128 monitor temperatures at different radial positions in the conductive body 116. The two thermocouples 126 and 128 and the lead wires 122 and 124 emerge from the second cavity 50 through the fitting 80 similar to the lead wires 104 of the heating unit 24.
The two-zone heating unit 114 can be used together with the cooling unit 34 to compensate for radial temperature variations in the wafer substrate 18. For example, heat is often dissipated more rapidly from a periphery of the wafer 18 than from its center. To compensate for this radial temperature variation, more power can be applied to the outer heating element 120 than to the inner heating element 118. However, conductivity tends to diminish the radial temperature gradient in the heating unit body 116, so zone control of the heating unit 114 alone may not be sufficient to maintain a uniform temperature distribution throughout the wafer substrate 18.
According to our invention, fluid pressure in the second cavity 50 can be controlled to conduct heat from the heating unit body 116, requiring one or more of the heating elements 118 and 120 to be over powered to maintain the desired overall temperature of the wafer substrate 18. Increasing the fluid pressure in the second cavity 50 tends to sustain temperature gradients in the heating unit body 116 induced by different zonal heating, and decreasing the fluid pressure in the second cavity 50 tends to diminish this effect. Thus, control over both the fluid pressure in the second cavity 50 and the power to he different heating elements 118 and 120 provides for controlling both the overall temperature of the wafer substrate 18 and the temperature distribution throughout the wafer substrate 18.
More or differently shaped heating zones could be used to affect other temperature distributions in the wafer substrate 18. The second cavity 50 could also be divided into independently controllable zones for further influencing temperature gradients. The cooling unit 34 could also be controlled such as by regulating the flow or temperature of the circulating coolant. These and many other changes or enhancements will be apparent to those of skill in art in accordance with the overall teachings of this invention. | A temperature controlled chuck (20) includes a heating unit (24) and a cooling unit (34). A first cavity (30) separates the heating unit (24) from a wafer substrate (18), and a second cavity (50) separates the cooling unit (34) from the heating unit (24). A first fluid delivery system (60) conducts fluid to the first cavity (30) to facilitate exchanges of heat between the heating unit (24) and the substrate (18). A second fluid delivery system (70) conducts fluid to the second cavity (50) to facilitate exchanges of heat between the heating unit (24) and the cooling unit (34). A control system (90) raises the temperature of the substrate (18) by increasing power to the heating unit (24) and by evacuating fluid from the second cavity (50) and lowers the temperature of the substrate (18) by reducing power to the heating unit (24) and by conducting fluid to the second cavity (50). | 2 |
[0001] This application claims the benefit of U.S. Provisional Application Serial No. 60/315,088, filed Aug. 27, 2001. This application is related to four concurrently filed co-pending patent applications, namely U.S. Ser. No. ______, entitled Configurable Apparatus and Method for Treating Carpal Tunnel Syndrome, U.S. Ser. No. ______, entitled Adjustable Apparatus and Method for Treating Carpal Tunnel Syndrome, U.S. Ser. No. ______, entitled Adaptable Apparatus and Method for Treating Carpal Tunnel Syndrome, U.S. Ser. No. ______, entitled Automatic Apparatus and Method for Treating Carpal Tunnel Syndrome, as well as co-pending patent application U.S. Ser. No. 10/199,747, entitled Apparatus and Method for Treating Carpal Tunnel Syndrome, filed Jul. 18, 2002, the contents of which are all hereby incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to treatment of carpal tunnel syndrome, and more particularly to a non-invasive apparatus and method for treatment of carpal tunnel syndrome.
BACKGROUND OF THE INVENTION
[0003] Carpal tunnel syndrome is a physiological disorder that afflicts over 850,000 people each year in the United States alone. In order to better understand the cause of the carpal tunnel syndrome and the difficulty in treating this serious disorder, a detailed explanation of the physiological factors and causes of carpal tunnel syndrome is presented below. Carpal tunnel syndrome is caused by a deleterious increase in pressure on the median nerve which passes through the carpal tunnel (or canal) in the hand, adjacent to the wrist. The deleterious increase in pressure, which is commonly brought on by prolonged repetitive motion of the hand and digits, is often caused by inflammation or damage to tendons for the hand which pass through the carpal tunnel along with the median nerve. Pressure increases can also be caused by narrowing of the carpal canal and by generalized swelling of the structures in the hand. Thus, when the carpal tunnel is narrowed from ligament shortening, muscle development or structural inflammation, the median nerve is undesirably compressed.
[0004] The carpal tunnel is formed by the eight carpal bones of the hand adjacent the wrist, which bones are arranged in two rows forming a generally U-shaped inverted arch-like “tunnel” structure. The three large carpal bones of the proximal row (i.e., closest to the chest), beginning laterally (i.e., from the outside with the hand directed downward and the palm facing forward), are the scaphoid, lunate, and triquetrum; the smaller pisiform bone sits on the palmar surface of the triquetrum. The distal row, from lateral to medial, consists of the trapezium, trapezoid, capitate, and hamate carpal bones. The vault of the carpal tunnel is formed by the carpal ligament and the flexor retinaculum. Nine tendons, their tendon sheaths, and the median nerve pass through the tunnel.
[0005] The carpal ligament is made of collagen and elastin and extends from the pisiformis and hamulus of hamate bones on the ulnar aspect of the tunnel to the tubercle (i.e., projection) of trapezium and the tubercle of the scaphoid bones on the radial (i.e. lateral) aspect of the carpal tunnel. The flexor retinaculum also stretches across the carpal tunnel and attaches to, on the medial aspect of the carpal tunnel, the pisiform bone and the hook of hamate, and, on the lateral aspect, the tubercle of the scaphoid and trapezium bones. The proximal border of the flexor retinaculum corresponds generally to the transverse skin crease at the base of the hand/wrist. The carpal ligament and flexor retinaculum, along with the carpal bones, form the restricted space through which the median nerve and several tendons pass.
[0006] Symptoms of carpal tunnel syndrome include tingling sensation in the hand, discomfort, numbness, and pain localized in the hand or radiating up the arm to the shoulder. All of these symptoms can occur during the day or can make the patients wake up at night. In advanced cases, there is atrophy and weakness of the thenar area of the hand which may weaken the grip and cause objects to fall out of the hand.
[0007] Conventional treatment of carpal tunnel syndrome is divided into surgical (invasive) and conservative (non-invasive). Surgical treatment consists of making an incision on the palmar aspect of the hand and splitting the carpal ligament, thus partially opening the carpal tunnel and relieving the pressure. This procedure, while occasionally successful, often has negative consequences, which include, but are not limited to, non-resolution of symptoms often requiring a second surgery, pain in the area of the scar, and injury to the superficial palmar branch of the median nerve causing persistent neurologic symptoms such as loss of full control over the hand. Furthermore, this procedure is very expensive. Understandably, surgical treatment is often considered as a last option.
[0008] Conservative, non-invasive treatment is typically separated into three categories—mild, moderate and alternative. Mild treatments may involve the use of anti-inflammatory medications, application of resting hand splints, physical therapy, modification of patient's activities that cause the condition, and even a change in the patient's job. Moderate treatments involve one or more mild treatments coupled with cortisteriod injections. Finally, alternative methods include acupuncture, massage, application of magnets, tai-chi exercises, and the like.
[0009] However, none of the above treatments have produced uniformly positive results. While some treatments may alleviate the symptoms of carpal tunnel syndrome in individual patients, the symptoms often return when the course of treatment is terminated. Furthermore, one of the main disadvantages of the various treatment approaches is that they must be delivered by a healthcare provider such as a physician or a physical or occupational therapist. This adds a significant level of inconvenience to the patient who must allocate time to visit the healthcare provider for injections and/or physical therapy. Medications that are used to provide relieve from the pain and discomfort caused by carpal tunnel syndrome also suffer from a number of disadvantages. For example, certain medications have undesirable side effects or interactions with the patient's other medications, if any. As a result, a number of techniques for treating carpal tunnel syndrome that address at least some of the above problems have been developed over the years. Some merely maintain the patient's hand in a neutral position (such as the device disclosed in U.S. Pat. No. 5,014,689) to prevent the symptoms from worsening. Another approach involved mechanical stretching of the carpal ligament, as disclosed in U.S. Pat. No. 5,256,136. Yet another series of techniques advocated placement of a compression bracelet on the forearm (U.S. Pat. No. 5,441,058), or on the wrist (U.S. Pat. No. 5,468,220) to apply a predetermined pressure on certain portions of the forearm, or wrist, respectively, in order to widen the carpal tunnel and thus provide relief to the patient suffering from carpal tunnel syndrome.
[0010] However, the above-described previously known devices suffer from a crucial disadvantage. Application of pressure to different portions of the forearm and/or the wrist only has a minimal effect on widening the carpal tunnel, and may only provide temporary relief from carpal tunnel syndrome rather than eliminating or suppressing the condition.
[0011] Further development in the area of mechanical treatment of carpal tunnel syndrome continued, and eventually resulted in discovery of the Porrata principle, disclosed in the commonly assigned U.S. Pat. No. 6,146,347 to Humberto Porrata, that provides a novel and advantageous device and method for treating carpal tunnel syndrome that solve the problems posed by previously known devices and techniques. Most importantly, research conducted in conjunction with development of the Porrata device, has shown that carpal tunnel syndrome may be treated with great effectiveness by precise controlled transverse stretching of the carpal ligament and the flexor retinaculum. The 6,146,347 patent disclosed a splint-like device that fit over the patient's hand and a portion of the wrist. The device included rigid sections for contacting the thenar and hypothenar portions of the hand and a selectable active pressure source that, when actuated, applied pressure to the dorsal portion of the patient's hand opposed by the forces delivered by the thenar and hypothenar sections of the device in such a manner, as to transversely stretch the carpal ligament and the flexor retinaculum in a comfortable and controlled manner.
[0012] Nevertheless, the device of the 6,146,347 patent is susceptible to improvement. First, because of its construction it generally must be fabricated in different sizes to fit various patients, and patients with unusual hand sized or shapes may need custom-fabricated devices. Second, it generally requires an active adjustable pressure source such as a bladder and pump combination for delivering pressure to the dorsal portion of the hand.
[0013] It would thus be desirable to provide an apparatus and method for treating carpal tunnel syndrome by stretching the carpal ligament and the flexor retinaculum of a patient's hand in a comfortable and controlled manner. It would further be desirable to provide an apparatus and method for treating carpal tunnel syndrome embodied in a device that is dynamically adaptable to patients of various physical characteristics. It would also be desirable to provide an apparatus and method for treating carpal tunnel syndrome embodied in a device that is easy and inexpensive to manufacture.
SUMMARY OF THE INVENTION
[0014] The apparatus and method of the present invention advantageously overcome the problems and drawbacks of previously known approaches for treating carpal tunnel syndrome. Similarly to the device disclosed in the commonly assigned U.S. Pat. No. 6,146,347, which is hereby incorporated by reference in its entirety, the main objective of the present invention is to apply the Porrata principle to transversely stretch the carpal ligament and the flexor retinaculum, as well as the superficial structures and muscles of the hand, in a safe manner under precise control of the patient or a healthcare professional. The apparatus and method of the present invention enable the Porrata principle to be implemented in a device that may be readily used by patients with any size or shape hands. Furthermore, the inventive apparatus is very simple and inexpensive to manufacture.
[0015] Controlled and monitored use of the inventive apparatus dynamically treats carpal tunnel syndrome through the application of pressure to portions of the palm of the hand (in the thenar and hypothenar areas) while at the same time providing application of pressure, in the opposite direction, to a portion of the dorsum of the hand. This procedure stretches the carpal ligament, the flexor retinaculum, and superficial structures and muscles of the hand in the palmar aspect of the hand, in a readily, safely controllable and comfortable manner.
[0016] Considering that the constitutions of the carpal ligament and the flexor retinaculum are soft tissue composed of collagen and elastin, stretching the carpal ligament and the flexor retinaculum is effective for decreasing compression on the median nerve by increasing the diameter of the tunnel and decreasing the rigidity of the retinaculum and the carpal ligament, thus alleviating the symptoms of carpal tunnel syndrome.
[0017] Various embodiments of the inventive apparatus commonly include a housing for receiving the patient's hand with an open top portion and with two internal regions adapted and configured to contact the thenar and hypothenar regions of the patient's palm, while a closeable cover that fits over the open top region of the housing includes a pressure element positioned and configured to apply pressure to the dorsal portion of the hand when the cover is depressed and/or closed.
[0018] Accordingly, the inventive apparatus is inexpensive and readily usable by any patient to prevent progression of carpal tunnel syndrome and to provide relief from symptoms by increasing the cross sectional area of the carpal tunnel, thus decreasing compression on the median nerve and decreasing the resulting symptoms.
[0019] Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In the drawings, wherein like reference characters denote like elements throughout the several views:
[0021] [0021]FIG. 1 is a cross section view of a first embodiment of the inventive apparatus for treating carpal tunnel syndrome;
[0022] [0022]FIG. 2 is an isometric top view of the first embodiment of the inventive apparatus for treating carpal tunnel syndrome of FIG. 1;
[0023] [0023]FIG. 3 is a cross section view of the first embodiment of the inventive apparatus for treating carpal tunnel syndrome of FIG. 1 during utilization.
[0024] [0024]FIG. 4 is a cross section view of a second embodiment of the inventive apparatus for treating carpal tunnel syndrome;
[0025] [0025]FIG. 5 is a cross section view of a third embodiment of the inventive apparatus for treating carpal tunnel syndrome;
[0026] [0026]FIG. 6 is a cross section view of a fourth embodiment of the inventive apparatus for treating carpal tunnel syndrome;
[0027] [0027]FIG. 7 is a cross section view of a fifth embodiment of the inventive apparatus for treating carpal tunnel syndrome;
[0028] [0028]FIG. 8 is a cross section view of a sixth embodiment of the inventive apparatus for treating carpal tunnel syndrome; and
[0029] [0029]FIG. 9 is an isometric top view of the sixth embodiment of the inventive apparatus for treating carpal tunnel syndrome of FIG. 6.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0030] The present invention is described with reference to various materials that compose the inventive structures and elements thereof, and to various devices for selectively applying pressure to a specific area of the hand, by way of example only—it should be understood that the apparatus and method of the present invention may be utilized with any materials or selective pressure sources having properties similar to those described in the exemplary embodiments, without departing from the spirit of the invention.
[0031] The essence of the Porrata approach, disclosed and described in greater detail in the above-incorporated U.S. Pat. No. 6,146,347, involves applying pressure to a portion of the top surface of the hand (i.e., the central dorsal region), while at the same time applying opposing pressure to the thenar and hypothenar regions of the palm. The apparatus and method of the present invention advantageously implement the Porrata principle in a simple to use device that works equally well with different hand shapes and sizes.
[0032] Referring now to FIG. 1, a first embodiment of an inventive apparatus 10 is shown. The apparatus 10 includes a housing 12 with a first support element 14 for supporting the thenar region of the hand, and a second support element 16 for supporting the hypothenar region of the hand. The housing 12 has side walls 11 and may be composed of a rigid material such as metal, hard plastic or wood, or a resilient material such as fiberglass or resilient plastic, or a combination thereof. The support elements 14 , 16 may be rigid portions of the housing 12 composed of the same material or, alternately, may incorporate respective resilient comfort elements 28 , 30 to improve contact with the respective thenar and hypothenar regions of the hand and to improve patient comfort. The support elements 14 , 16 are substantially parallel to each other generally along the longitudinal axis of the patient's hand. The comfort elements 28 , 30 may be composed of any resilient material, including but not limited to: soft plastic, silicone gel, padding, foam, spring elements, and a fluid or air-filled bladder. Optionally, the comfort elements 28 , 30 may incorporate active pressure sources such as inflatable bladders or electromagnetic plates. The support elements 14 and 16 may be adjustable in position and orientation to better correspond to the size and shape of the patient's hand. Alternatively, the support elements 14 and 16 may incorporate active pressure sources such as inflatable bladders or electromagnetic plates.
[0033] A cover 18 is pivotably attached to the housing 12 by a hinge element 20 , which may be a hinge or a piece of a flexible material. The cover 18 includes an elongated pressure element 22 disposed along its length and configured to contact a substantially central dorsal region of the hand along its longitudinal axis when the cover 18 is closed. Preferably, the pressure element 22 is sized to cover a sufficiently large portion of the surface of the dorsal portion of the hand, particularly in the transverse direction, to reduce the pressure applied to any particular nerve or artery in the hand. The pressure element 22 may be composed of a rigid material, such as metal, wood, plastic or fiberglass, or it may be composed of a resilient material such as soft plastic, silicone gel, padding, foam, and a fluid or air-filled bladder, or a combination of one or more resilient and rigid materials.
[0034] Referring now to FIG. 2, a different view of the apparatus 10 is shown. FIG. 2 also shows that the apparatus 10 may also include an electronic device 40 that includes a laser or similar device adapted to specifically denature the proteins that make up the ligaments in the body, thus making it easier to stretch the ligaments. The electronic device 40 is preferably aligned with the flexor retinaculum or carpal ligament as the hand is placed in the apparatus 10 . The electronic device 40 may also include conventional sensors to measure the amount of stretching or elongation of the flexor retinaculum or carpal ligament through, e.g., tension measurements or displacement of carpal bones.
[0035] Referring now to FIG. 3, the operation of the apparatus 10 is shown. A patient places a hand 300 into the housing such that the thenar region of the palm is positioned over the support element 14 and the hypothenar region of the palm is positioned over the support element 16 (or over optional comfort elements 28 , 30 ). The wrist of the hand 300 is received through an open side portion of the housing 12 . The cover 18 is closed over the open top portion of the housing 12 such that the pressure element 22 contacts and presses down on the central dorsal region of the hand 300 along its longitudinal axis, which pressure is balanced and opposed by a second force formed by retaining action of the support elements 14 , 16 exerted on the respective thenar and hypothenar regions of the hand. These opposing forces cause carpal bones of the hand to separate to stretch a carpal ligament and a flexor retinaculum of the hand, thus implementing the Porrata principle to widen the carpal canal and provide treatment of carpal tunnel syndrome to the patient.
[0036] Referring back to FIG. 1, an optional releasable locking device 24 , 26 may be positioned on the cover 18 and housing 12 , respectively to maintain the cover 18 in a locked position when it is closed over the hand. The locking device 24 , 26 may be a clasp, a hook and loop combination (i.e. Velcro), a latch or any other releasable retaining device.
[0037] Referring now to FIG. 4, a second embodiment of the inventive apparatus is shown as an apparatus 50 . The apparatus 50 includes a housing 52 with a side 54 , having a first set of independent support elements 62 , 64 for supporting the thenar region of the hand, and a second side 56 having a second set of independent support elements 58 , 60 for supporting the hypothenar region of the hand. The housing 52 may be composed of a rigid material such as metal, hard plastic or wood, or a resilient material such as fiberglass or resilient plastic, or a combination thereof. The independent support elements 58 , 60 , 62 , 64 may be composed of a resilient material, including, but not limited to: soft plastic, silicone gel, padding, foam, and a fluid or air-filled bladder. Alternatively, they may be composed of a rigid material having a resilient lining, or spring elements 55 in contact with sides 54 and 56 . Multiple independent support elements 58 , 60 , 62 , 64 are advantageous because they enable the apparatus 50 to adjust to the shape of the patient's hand. While only two independent support elements are shown on each side 54 , 56 , a greater number of independent support elements may be implemented without departing from the spirit of the present invention.
[0038] A cover 66 is pivotably attached to the housing 52 by a hinge element which may be a hinge or a piece of a flexible material. The cover 66 includes an elongated pressure element 68 disposed along its length and configured to contact a substantially central dorsal region of the hand along its longitudinal axis when the cover 66 is closed. The pressure region 68 may be composed of the same material as the cover 66 , such as metal, wood, plastic or fiberglass, or it may incorporate a resilient contact pad 70 composed of a resilient material such as soft plastic, silicone gel, padding, foam, and a fluid or air-filled bladder. An optional releasable locking device 72 , 74 may be positioned on the cover 66 and housing 52 , respectively to maintain the cover 66 in a locked position when it is closed over the hand. The locking device 72 , 74 may be a clasp, a hook and loop combination (i.e. Velcro), a latch, or any other releasable retaining device.
[0039] Referring now to FIG. 5, a third embodiment of the inventive apparatus is shown as an apparatus 100 . The apparatus 100 is similar in construction and operation to the apparatus 10 of FIG. 1, except that a first mobile cylindrical roller 108 is positioned along a thenar support region 104 , and a second mobile cylindrical roller 110 is positioned along a hypothenar support region 106 . The cylindrical rollers are configured such that when a patient places their palm on the rollers 106 , 108 and a cover 112 is closed, the pressure exerted by a pressure element 114 on the dorsal part of the hand causes the rollers 106 , 108 to move away from a central portion of the palm along the respective sides 104 , 106 to contact and support the respective thenar and hypothenar regions of the palm. Thus, this embodiment provides a dynamically adjustable support to the thenar and the hypothenar regions of the hand irrespective of the hand's size.
[0040] Referring now to FIG. 6, a fourth embodiment of the inventive apparatus is shown as apparatus 150 . The apparatus 150 is similar in operation to the apparatus 10 of FIG. 1 (for example, sides 156 and 156 correspond to support elements 14 and 16 , and comfort elements 158 and 160 correspond to comfort elements 28 and 30 ), except that a cover 162 is composed of a flexible material or a resilient stretchable material. A pressure element 164 may be configured to move along the cover 162 via an adjustment device 166 . For example, the pressure element 164 (which may be similar to the pressure elements of the various other embodiments described herein) may include a knob seated within a slot in cover 162 by which the user may slide the pressure element 164 within the slot. This arrangement is advantageous because stretching tension can be applied to the cover 162 to thereby exert greater pressure on the dorsal region of the hand via the pressure element 164 . This adjustment device 166 may be incorporated into any of the other embodiments described herein. The adjustment device 166 may include or be coupled with a pressure measuring gauge allowing the user to increase the pressure on the dorsal portion of the hand to a pre-determined level. A releasable retaining device 168 , 170 is configured to releasably retain the cover 162 when it is closed and is optionally configurable to maintain different levels of tension in the cover 162 when the cover 162 is stretchable.
[0041] Referring now to FIG. 7, a fifth embodiment of the apparatus of present invention is shown as an apparatus 200 . The apparatus 200 is similar in operation to the apparatus 100 of FIG. 3 except that rollers 208 , 210 in contact with spring elements 212 , 214 move along a bottom of a housing 202 , rather than at an angle as in apparatus 100 of FIG. 3. Apparatus 200 includes sides 204 , 206 , cover 216 with attached pressure element 218 , hinge 224 , and optional releasable locking device 220 , 222 .
[0042] Referring now to FIG. 8, a sixth embodiment of the inventive apparatus is shown as an apparatus 250 . The apparatus 250 includes a housing 252 having a generally semi-circular cross-section, with a first support element 254 for supporting the thenar region of the hand disposed along one side of an internal concave region of the housing, and a second support element 256 for supporting the hypothenar region of the hand disposed along the other side of the concave region of the housing. The housing 252 may be composed of a rigid material such as metal, hard plastic or wood, or a resilient material such as fiberglass or resilient plastic, or a combination thereof. The support elements 254 , 256 may be composed of any resilient material, including but not limited to: soft plastic, silicone gel, padding, foam, spring elements, and a fluid or air-filled bladder. Optionally, the support elements 254 , 256 may incorporate active pressure sources, such as inflatable bladders or electromagnetic plates. The support elements 254 , 256 may be adjustable in position and orientation to better correspond to the size and shape of the patient's hand. Alternatively, the support elements 254 , 256 may be composed of a substantially rigid material such as metal, plastic, wood or fiberglass.
[0043] A cover 258 is pivotably attached to the housing 252 by a hinge element 266 , which may be a hinge or a piece of a flexible material. The cover 258 includes an elongated pressure element 260 disposed along its length and configured to contact a substantially central dorsal region of the hand along its longitudinal axis when the cover 258 is closed. The pressure element 260 may be composed of a rigid material, such as metal, wood, plastic or fiberglass, or it may be composed of a resilient material such as soft plastic, silicone gel, padding, foam, and a fluid or air-filled bladder, or a combination of one or more resilient and rigid materials. Referring now to FIG. 9, a different view of the apparatus 250 is shown.
[0044] Referring back to FIG. 8, an optional releasable locking device 262 , 264 may be positioned on the cover 258 and housing 252 , respectively to maintain the cover 258 in a locked position when it is closed over the hand. The locking device 262 , 264 may be a clasp, a hook and loop combination (i.e. Velcro), a latch, or any other releasable retaining device.
[0045] It should be noted that the individual elements shown in the various embodiments may be readily utilized in different embodiments or mixed without departing from the spirit of the invention. For example, the flexible cover 162 of the apparatus 150 of FIG. 6 may replace the rigid cover of the apparatus 10 of FIG. 1. In addition, the electronic device 40 illustrated in FIG. 2 may be incorporated into the various other embodiments. Furthermore, while cross sections of the various embodiments of the inventive apparatus are shown to be of rectangular or elliptical in shape, the cross section of the inventive apparatus may comprise any other geometrical shape without departing from the spirit of the invention.
[0046] Thus, while there have been shown and described and pointed out fundamental novel features of the invention as applied to preferred embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices and methods illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto. | The apparatus of the present invention stretches the carpal ligament and the flexor retinaculum, as well as the superficial structures and muscles of the hand, in a safe manner under precise control of the patient or a healthcare professional. Various embodiments of the inventive apparatus include a housing for receiving the patient's hand with an open top portion and with two internal regions adapted and configured to contact the thenar and hypothenar regions of the patient's palm, while a closeable cover, that fits over the open top region of the housing, includes a pressure element positioned and configured to apply pressure to the dorsal portion of the hand when the cover is depressed and/or closed such that opposing forces of the internal regions pressing on the thenar and hypothenar regions of the palm while the pressure element is pressing on the dorsal portion of the hand cause the carpal ligament and the flexor retinaculum to stretch expanding the carpal tunnel and relieving pressure on the median nerve. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is directed to a screen printer, and more particularly, to an improvement in the print roller system used in the screen printer.
2. Description of the Prior Art
U.S. Pat. No. 2,965,020 shows a conventional type of dual roller screen printer system.
U.S. Pat. No. 3,804,011 shows a conventional single roll screen printer.
SUMMARY OF THE INVENTION
The invention is directed to a modification in the conventional flatbed screen printer which utilizes reciprocating dual print rollers to squeeze the printing ink through the patterned area of the screen. Wiper or scraper blades are provided adjacent each roller. The wiper blades engage the screen and wipe the surface of the screen contacted by the rollers. The wiper blades move in a reciprocating movement with the rollers and the wiper blades which is trailing its roller, when the roller is moving in one direction, will be pushing printing ink therebefore so that a supply of ink will be available to its adjacent roller when it changes its direction of movement and reciprocates back in the opposite direction from which it initially traveled.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a showing of the normal print roller structure; and
FIG. 2 is a showing of the modified print roll structure utilizing the inventive concept herein.
DESCRIPTION OF THE PREFERRED EMBODIMENT
An inherent problem exists with a flat screen printer when print rollers of 2" or more in diameter are utilized. The problem that occurs is the uneven ink application throughout the printing stroke and particularly, at the beginning of the printing stroke. The trailing print roller comes to rest at the end of the each stroke approximately 3" beyond the patterned area of the screen. On the return stroke, the trailing print roller is now the leading print roller and it picks ink out of the reservoir which exists between the two print rollers. As the lead roller picks the ink out of the reservoir, the ink must move around the periphery of the roller and then be deposited on the screen in front of the lead roller to thus form the front ink wedge. If a 3" diameter roller is used, it will take 7" of travel before the ink that is picked up by the lead roller is moved around the periphery of the roller and deposited on the screen. Since there are only 3" of blank screen, the roller will have to travel 4" into the patterned area before ink is in contact with the screen resulting in a 4" wide light area of printing. Such a problem occurs at both ends of a pattern since the pattern is printed through the use of reciprocating rolls.
The invention herein utilizes a scraper blade which is placed in front of the rollers and attached to the print roller frame. The scraper blades generate a supply of ink so it will be available to the leading roller when it first moves off into the pattern area. There is normally excess ink left on a screen by the print rollers, and in addition to scraping off this excess ink, the scraper blade generates a reservoir of ink for the leading roller as it first moves out into a patterned area.
In FIG. 1, there is shown a conventional dual roll print roller assembly such as that shown in U.S. Pat. No. 2,965,020. The structure of FIG. 1 is used with a flatbed screen printer which would utilize the screen 2 which has a patterned area 4 and a blank or nonpatterned area 6. The print roller assembly is composed of two rolls 8 and 10 which have a reservoir of ink 12 deposited therebetween. As shown on FIG. 1, the print roller assembly has just completed its stroke moving from the right to the left and is now ready to make its return stroke from the left to the right. A number of strokes of a print roller assembly is needed in order to get uniform printing and good penetration of ink into the material being printed under the screen 2. As can be seen in FIG. 1, a supply of ink 14 had been picked up by the roller 8 and moved in front of the roller as it was moving across the screen from the right to the left. It is important that this supply of ink 14 be available for roller 8 while the ink in the reservoir 12 is available for the roll 10 to force ink into the patterned area of the screen. With start of the roller assembly from the left to the right, it will be noted that there is no supply of ink in front of roller 10 which has now become the leading roller as the print roller assembly moves from the left to the right. As indicated above, the 3" leading roller 10 will require 7" of travel before ink is moved from the reservoir 12 around to region 16 in front of roller 10. This supply of ink will not appear until roller 10 is well within the patterned area 4. It should be noted also that the ink supply 14 is going to be left behind when the roller assembly moves to the right and, therefore, over a period of time, a buildup of ink would occur on the far left side of the blank portion of the screen and such a buildup would be undesirable.
Referring now to FIG. 2, the scraper blade structure modification herein is shown to overcome both the problem of a generation of an ink supply in the region 16 and additionally to help remove the ink supply 14 so that it does not build up on the left side of the screen. The rollers 8 and 10 are shown in FIG. 2 and a framework 18 is mounted above these rollers. The framework 18 is fixed to the framework 20 which carries the two rollers and moves them in a reciprocating manner. On either end of the framework 18 there was positioned scraper blades 22 and 24. These blades are made of a flexible material such as rubber or urethane so that they can conform generally to the countour of the patterned screen and will provide a wiping action on the upper surface of the screen. They are spaced approximately 1" from the roller that they are positioned adjacent thereto. That is, blade 22 would be approximately 1" from the periphery of roll 10 and blade 24 would be approximately 1" from the periphery of roll 8. Referring now to the ink buildup 14, it will be seen that as the roller assembly moves from the left to the right, scraper 24 will push the ink accumulation 14 along with the roller assembly so that the ink accumulation 14 will be not left on the left side of the screen. It should be noted that an ink accumulation 26 exists by scraper blade 22, and this ink accumulation is immediately available for utilization by roll 10 as it moves into the patterned area 4. This ink accumulation 26 is generated by scraping excess ink off the surface of the screen. The excess ink was that ink which was not picked up and moved along by the printing roll as the printing roll assembly moved from the right to the left. In addition, just as an accumulation of ink 14 would have been left on the left side of the screen, so an ink accumulation would have been left on the right side of the screen and the scraper blade 22 has moved this ink accumulation from the right side of the screen along with the roller assembly as it moved toward the left side of the screen, and the right side ink accumulation is part of the ink accumulation 26. Clearly, it can be seen that the scraper blade assembly modification to a conventional two roll print roller structure now provides adequate ink supply to large rollers when they are utilized with a flatbed screen printer. | Print rollers are used on a flatbed screen printer to force the ink through the screen. There is provided scraper blades on either side of the roller assembly so that on the return stroke of the roller assembly some of the printing ink is brought back to the lead roller when it starts its movement. This will insure a supply of ink to the lead roller when it moves into the pattern area of the screen thus giving a more uniform ink deposition across the pattern. | 1 |
This application is a continuation of application Ser. No. 08/274,853, filed Jul. 14, 1994, now U.S. Pat. No. 5,454,338, issued Oct. 3, 1995.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention relates generally to sewing machines and, more particularly, an apparatus for excluding lint from the interior of a sewing machine.
(2) Description of the Prior Art
One of the major problems in commercial sewing operations is lint. Once lint from the garment piece contacts oil from the sewing machine, it will spot fabric fed to the machine, wick oil from the machine and clog critical parts within the machine. Over the years, many approaches have been tried to solve the problem of lint. Operators have used vacuum and air blowing systems to try to prevent accumulation of lint.
For example, U.S. Pat. No. 4,709,645, issued to Jones et al., discloses a waste fabric and lint collection box for a sewing machine connected to a vacuum source in a waste removal system.
None of these systems have been entirely successful. The problem is now understood that once the lint contacts oil in the machine, no amount of vacuum or blowing can remove it from the machine or prevent it from spotting garments.
Thus, there remains a need for a new and improved lint barrier for a sewing machine which is operable to prevent lint from entering the interior of the sewing machine, thereby preventing spots on garments, oil loss and damage to critical parts within the machine.
SUMMARY OF THE INVENTION
The present invention is directed to a sewing machine having a lint barrier which excludes lint from entering the interior of the sewing machine having a machine housing enclosing the internal workings of the machine. The sewing machine also includes an oil cooler adapted to cool oil circulating through the sewing machine, the cooler including a radiator and an air source for moving air through the radiator. A conduit connects the air source to the interior of the sewing machine, whereby air is conducted through the conduit and into the interior of the sewing machine to maintain a positive pressure within the sewing machine interior, thereby preventing the entry of lint into the sewing machine interior.
Accordingly, one aspect of the present invention is to provide an apparatus for excluding lint from a sewing machine interior. The apparatus includes: (a) an air conduit having an outlet in communication with the sewing machine interior and an air inlet; and (b) an air source in communication with the air inlet, whereby air entering the air inlet and exiting the outlet produces a positive pressure in the sewing machine interior, thereby preventing the entry of lint into the sewing machine interior.
Another aspect of the present invention is to provide a sewing machine. The sewing machine includes: (a) a machine housing; (b) an oil cooler adapted to cool oil circulating through the sewing machine, the cooler including a radiator and an air source for moving air through the radiator; (c) a conduit having an inlet end in communication with the air source and an outlet end in communication with the interior of the sewing machine, whereby air is conducted through the conduit and into the interior of the sewing machine to maintain a positive pressure within the sewing machine interior, thereby preventing the entry of lint into the sewing machine interior.
Still another aspect of the present invention is to provide a method of excluding lint from the interior of a sewing machine. The method includes the steps of: (a) producing air under pressure; and (b) directing the pressurized air into the sewing machine interior to maintain a positive pressure within the sewing machine interior, thereby preventing the entry of lint into the sewing machine interior.
These and other aspects of the present invention will become apparent to those skilled in the art after a reading of the following description of the preferred embodiment when considered with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a commercial sewing machine with an air diverter constructed according to the present invention installed;
FIG. 2 is a partial sectional view of the sewing machine and air diverter illustrated in FIG. 1;
FIG. 3 is an enlarged perspective view of the air diverter; and
FIG. 4 is an enlarged side view of the air diverter illustrated in FIG. 3 taken along line 4--4.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following description, like reference characters designate like or corresponding parts throughout the several views. Also in the following description, it is to be understood that such terms as "forward", "rearward", "left", "right", "upwardly", "downwardly", and the like are words of convenience and are not to be construed as limiting terms.
Referring now to the drawings in general and FIG. 1 in particular, it will be understood that the illustrations are for the purpose of describing a preferred embodiment of the invention and are not intended to limit the invention thereto. As best seen in FIG. 1, an industrial sewing machine is shown having an air diverter constructed according to the present invention installed.
The sewing machine, in the absence of the improvements added by the present invention, is of a conventional design, and thus is not illustrated or described in detail. The sewing machine shown is a model 39500 manufactured by Union Special of Huntley, Ill. and includes a housing 10 enclosing the internal workings of the sewing machine including shuttle/hook and bobbin case. Access to the internal components within housing 10 is by way of cover 12 connected to housing 10 by hinge 14. The sewing machine is supported above a table 16 and driven by an external motor by a belt.
Since industrial sewing machines operate at very high speeds, e.g., 9000 stitches per minute, it is necessary to circulate oil about the critical moving parts. The oil, heated by friction from the moving parts, is cooled by passing it through a radiator 18, mounted below table 16. In the usual industrial sewing machine, the oil passing through the radiator 18 is cooled by blowing air from an air source through the radiator. However, in the present invention, oil passing through the radiator is cooled by drawing air into the radiator, i.e., the air is pulled through the radiator by a negative pressure as opposed to forcing air through the radiator by positive air pressure as is conventionally done. This is accomplished by mounting radiator 18 adjacent a cooling air supply, generally designated 20, consisting of an air source housing 22 which includes a plenum 23 enclosing a fan 24 driven by a electric motor. Housing 22 has an inlet 28 adjacent to the radiator 18 and an outlet 30. A filter 32 is positioned over inlet 28 to restrict the entry of dust into the interior of housing 22.
The reversal of the air flow through the radiator and into the housing enables the air source to also be used to produce a positive flow of air into the interior of the sewing machine by directing the air exhausted from air source 20 through an air diverter, generally designated 34, thereby pressurizing the interior of the sewing machine.
As best illustrated in FIGS. 3 and 4, air diverter 34 has an inlet in communication with air source 20 by way of tube 38 connected to housing outlet 30 and an air outlet 52 in communicating with the interior of the sewing machine. Air diverter 34 extends upwardly from air source 20 to the sewing machine through an opening 36 in table 16.
Air diverter 34 includes tube 38 and an air discharge chamber formed by a pair of spaced side walls 40 and 42 having front edges 44 and 46, respectively, a curved rear wall 48 and a front wall 50. The upper edge of front wall 50 is spaced from the forward edge of rear wall 48 to form a discharge port 52 therebetween. A horizontal top wall 54 joins the upper edges of side walls 40 and 42 and is spaced above port 52. Top wall 54 includes a leading edge 56 which, along with leading edges 44 and 46 of side walls 40 and 42, respectively, are shaped to be configuration of the sewing machine to provide a close fit adjacent the sewing machine interior. The lower edges of walls 40, 42, 48 and 50 are joined to the upper edge of pipe 38 which has an inlet end 60 opposite discharge port 52.
Cover 12 is rotatable about hinge 14 between an open position and a closed position. When cover 12 is in the open position, air diverter 34 can be positioned within or removed from opening 36 in table 16. In order to provide a positive air pressure within the interior of the sewing machine, air diverter 34 is positioned within opening 36, with the leading edges 44, 46 and 56 walls 40, 42 and 54, respectively, adjacent the interior of the sewing machine. Cover 12 is then rotated about hinge 14 to a closed position in which it cooperates with the walls of diverter 38 to direct air into the sewing machine interior.
Operation of the apparatus and attendant process is both simple and effective. Air produced by air source 20 is drawn into the plenum 23 formed by housing 22 through air inlet 28 and is discharged from housing 22 through outlet 30 connected to tube 38. The discharged air is then conveyed through air diverter 34 into the interior of the sewing machine by entering inlet 60 of conduit 38 and flowing upwardly into the air diverter, where it is exhausted through discharge port 52. As a result of the cooperation of walls 40, 42, 48 and 54, and the cooperation of cover 12, air is forced into the sewing machine interior producing a positive pressure within the interior of the sewing machine. This prevents lint and other airborne particles from entering the interior of the machine and forming a solid with the oil in the machine.
In the preferred embodiment, air is directed into the sewing machine interior at a rate of up to about 350 cubic feet per minute (10,000 liters per minute). However, it will be understood that some sewing machines may have less openings and, accordingly, a lower air flow rate will be sufficient. Also, in the preferred embodiment, it has been found that the air directed into the sewing machine interior only requires a pressure of between about 0.05 and 0.5 inches of water (1.3 and 13 millimeters of water) in order to be effective. This is surprising in view of the prior art air and vacuum systems which produced substantially larger pressure differentials.
Certain modifications and improvements will occur to those skilled in the art upon a reading of the foregoing description. By way of example, the shape of the air diverter, especially the leading edges of the side walls, can be modified to fit other machine configurations. Also, the structure of the air diverter can be such that the air is directed into the interior of the sewing machine by the air diverter configuration without any cooperation from the machine cover. In addition, the air source used to direct air into the sewing machine interior can be different from the air source used to cool the oil. Furthermore, when using a common air source to cool oil passing through the radiator and to maintain a positive pressure within the interior of the sewing machine, the air source can blow air through the radiator and into the housing, instead of drawing the air through the radiator as shown in the preferred embodiment. Finally, the invention can be practiced without using a radiator or coiling coil by using a fan in an enclosure or other source of clean, low pressure air. It should be understood that all such modifications and improvements have been deleted herein for the sake of conciseness and readability but are properly within the scope of the following claims. | A lint barrier for a sewing machine which excludes lint from entering the interior of the sewing machine having a machine housing enclosing the internal workings of the machine. The sewing machine also includes an oil cooler adapted to cool oil circulating through the sewing machine, the cooler including a plenum, a radiator and an air source for moving air through the radiator. A conduit connects the air source to the interior of the sewing machine, whereby air is conducted through the conduit and into the interior of the sewing machine to maintain a positive pressure within the sewing machine interior, thereby preventing the entry of lint into the sewing machine interior. | 5 |
BACKGROUND OF THE INVENTION
This invention relates generally to the assembly of structures, and in particular to a press for manufacturing trusses which provides several advantageous features.
Pre-manufactured structural frameworks, such as trusses, are widely used in the construction industry for forming a roof, wall panel, floor, or other building component. The truss is assembled to the correct specifications at a factory and then shipped to a construction site. Each truss includes a collection of structural members made of wood, plastic, or metal which are held together by fasteners, such as nailing or connector plates. Efficient assembly of the truss is facilitated by a press apparatus which drives the connector plates into assembled precut structural members where they intersect or abut each other.
In one widely used type of system, a press is suspended from an overhead carriage for movement between several splice pedestals (or stands) supporting the structural members in assembled position. Each of the pedestals includes a holder for holding a lower connector plate at a position below the structural members and bridging lower surfaces of the structural members at their intersection or abutment. An upper connector plate is placed over the joint so that it bridges upper surfaces of the structural members. The press has a C-shaped frame which carries upper and lower platens adapted to be positioned above and below the respective upper and lower connector plates. Actuation of a hydraulic powered cylinder causes the upper platen to move downwardly toward the lower platen and press the joint so that the connector plates are driven into the structural members thereby connecting the structural members.
There has been growing demand for larger, heavier trusses using larger sizes of connector plates, such as 8×8 inches and 10×12 inches, which require a larger capacity press, e.g., on the order of about 37.5 to 50 tons instead of 25 tons. Unfortunately, existing presses have a number of drawbacks which degrade their effectiveness in applying such a large force without substantial increases in size and weight of the frame.
Frames of the prior art are prone to fatigue damage. Typically, a frame has two major structural parts including an inner peripheral rim defining the inside edge of the C-shape and an outer peripheral rim defining the outer edge. For lower cost manufacturing (e.g., by forging of steel), the frame has a profile which is not a substantially rounded “C”, but rather a generally rectangular “C”. Consequently, the frame has two substantially 90° turns at corners of the C-shape, separating the generally horizontal and vertical portions of the “C”. During operation, the frame is exposed to a reaction force urging apart the upper and lower platens. Unfortunately, stress concentrations arise at each turn which produce a local stress greater than a nominal stress. Consequently, the frame tends to develop fatigue cracks and fail sooner than should be expected for its size and loading. Aggravating this problem is that the majority of the load is transmitted through the inner peripheral rim, which consequently exhibits the earliest fatigue damage. The inner and outer rims are divided such that the loads carried by each are separate, without the added stability or efficiency if the load was shared in a structural framework.
Systems of the prior art are not designed for rapid maintenance and repair. The hydraulic cylinder for driving the upper platen includes a tubular body holding a reciprocally movable piston connected to a movable rod. That body is typically welded to the frame. Consequently, the body carries load and is subject to fatigue damage, particularly along the weld. Replacement of the cylinder is difficult and requires substantial down time. Moreover, maintenance work on the cylinder or its replacement with a new or differently sized cylinder and piston is a major repair effort. There is no flexibility in quickly substituting differently sized cylinders for carrying different loads tailored to the truss. The cylinder and its tubular body are not “off the shelf” items.
The upper platen is subject to failure when used with high loadings. Periodically, the platen inadvertently presses a non-flat object, such as due to operator error or due to an incorrectly positioned stop on the pedestal. That exposes a portion of the platen to an even greater load which frequently leads to permanent deflection or failure.
Operationally, presses of the prior art are inefficient. An operator controls a switch to activate the hydraulic cylinder and apply force through the cylinder to the joint. The operator makes a visual judgment of whether the connector plates are completely embedded into the structural members, and releases the switch so that the platens may separate. Often, the operator misjudges that time and must conduct one or more repetitive cycles of force application. Further, the press may be limited in magnitude of force due to the aforementioned structural drawbacks and cylinder size and requires several cycles to embed larger connector plates. Thus, substantial delays may occur in the construction of a roof truss.
SUMMARY OF THE INVENTION
Among the several objects and features of the present invention may be noted the provision of an apparatus for pressing connector plates into structural members which inhibits fatigue damage; the provision of such an apparatus which distributes load effectively; the provision of such an apparatus which is easy to maintain and repair; the provision of such an apparatus which applies greater force without a corresponding increase in mass of the frame; and the provision of such an apparatus which is operationally efficient.
In general, a press according to the present invention is for use in pressing connector plates into opposing surfaces of structural members which are to be secured together at one or more joints to form a structure. The press comprises first and second platens sized and shaped for engaging connector plates to press the connector plates into the structural members. A frame includes a first mounting portion mounting the first platen, a second mounting portion mounting the second platen and a third portion interconnecting the first and second mounting portions. The frame positions the first and second platens in generally opposed relation for relative movement toward each other to press connector plates into the structural members and away from each other to clear the structural members and connector plates. An actuator is mounted on the frame for applying a force to at least one of the first and second platens to forcibly move the platen. The third portion of the frame is free of straight sections thereby to inhibit the concentration of stress in one location of the frame in operation of the press.
In another aspect, a press of the present invention is for use in pressing connector plates into opposing surfaces of structural members which are to be secured together at one or more joints to form a structure. The press comprises first and second platens sized and shaped for engaging connector plates to press the connector plates into the structural members. A frame mounts the first and second platens in generally opposed relation for relative movement toward each other to press connector plates into the structural members and away from each other to clear the structural members and connector plates. An actuator is mounted on the frame for applying a force to at least one of the first and second platens to forcibly move the platen. The frame includes a peripheral inner rim, a peripheral outer rim and ribbing spanning and connecting the inner rim to the outer rim.
In yet another aspect, a press of the present invention is for use in pressing connector plates into opposing surfaces of structural members which are to be secured together at one or more joints to form a structure. The press comprises first and second platens sized and shaped for engaging connector plates to press the connector plates into the structural members. A frame mounts the first and second platens in generally opposed relation for relative movement toward each other to press connector plates into the structural members and away from each other to clear the structural members and connector plates. An actuator is mounted on the frame for applying a force to at least one of the first and second platens to forcibly move the platen. A timer control is adapted for automatically holding the actuator at a preselected force for a preselected period of time and then to move at least one of the first and second platens away from the other platen to release the force.
In still a further aspect, a press of the present invention is for use in pressing connector plates into opposing surfaces of structural members which are to be secured together at one or more joints to form a structure. The press comprises first and second platens arranged for placement proximate the opposing surfaces of the structural members and relatively movable toward and away from one another. The platens are configured for pressing the connector plates into the structural members. A frame mounts the platens, the frame having a generally C-shaped contour with an inner peripheral load carrying surface and an outer peripheral load carrying surface. The inner peripheral load carrying surface of the frame has a shape which defines a segment of a circle such that forces applied to the frame while the platens are pressing the connector plates are transmitted in a loadpath through the inner peripheral load carrying surface which is smooth and substantially free from discontinuity to inhibit concentration of stress at any position along the inner peripheral load carrying surface and thereby strengthen the frame against fatigue damage.
Other objects and features of the present invention will be in part apparent and in part pointed out hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevation of a press system and support pedestals holding a truss;
FIGS. 2 and 3 are front and side elevations, respectively, of a press of the press system;
FIG. 4 is similar to FIG. 3 but shows the press pressing connector plates into opposing surfaces of structural members which are to be secured together;
FIG. 5 is a section on line 5 — 5 of FIG. 3 ;
FIG. 6 is a section on line 6 — 6 of FIG. 3 ;
FIG. 7 is a section on line 7 — 7 of FIG. 5 ;
FIG. 8 is a vertical section of a frame of the press;
FIG. 9 is a section on line 9 — 9 of FIG. 8 ;
FIG. 10 is a perspective of a cylinder mount of the apparatus;
FIGS. 11 and 12 are front and right side elevations, respectively, of the cylinder mount of FIG. 10 ;
FIG. 13 is a fragmentary elevational section showing the engagement of the cylinder mount and the C-frame; and
FIG. 14 is a schematic of a control system of the invention.
Corresponding reference characters indicate corresponding parts throughout the views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, FIG. 1 shows a press system according to the present invention, generally indicated at 10 , for assembling structures such as trusses. The apparatus 10 includes a press, indicated generally at 12 , which is suspended by a suspension assembly 14 from an overhead rail 16 for movement between a series of conventional splice pedestals 18 . The suspension assembly 14 includes a carriage assembly 20 movable along the rail, a pivotal boom 22 attached to the carriage by a hanger 24 and swivel 26 , and a yoke 28 suspended from one end of the boom. The press is counterbalanced by a power and control assembly 30 including a hydraulic power unit 32 , counterweight (not shown), electrical panel and control unit 34 , and manifold 36 on the opposite end of the boom. The press 12 , suspension assembly 14 , and power and control assembly 30 are considered collectively to be a press system. Pedestals 18 hold structural members 38 , such as pre-cut timbers, which are to be secured together by the press at their intersections with connector plates 40 . Although the press 12 is shown operating on wooden components (i.e., pre-cut timbers), the press may be used to press connector plates into components made of other materials.
Referring to FIGS. 2 and 3 , the press 12 comprises a frame 44 which supports first and second platens 46 , 48 for relative movement toward one another to press the connector plates into the timbers, and away from one another so that the platens may clear the timbers and connector plates so that the press may be moved to another position. In the illustrated embodiment, the first platen 46 is a lower platen and is fixedly attached to a first portion 50 of the frame 44 , such as by welding, and strengthened by two lateral support plates 52 . The second platen 48 is an upper platen movable via a hydraulic powered cylinder 53 (broadly, “actuator”) having a tubular body 56 ( FIG. 4 ) holding a movable piston and rod assembly 54 . The cylinder body 56 , and hence the upper platen 48 , are mounted on an actuator mount 58 , constituting a second portion of the frame 44 . The platens 46 , 48 are generally rectangular in planform shape and of sufficient size for engaging an entire extent of a connector plate 40 , with an exemplary size of each platen being 10×16 inches. An exemplary diameter of the bore of cylinder body 56 is six inches. However, the platens and cylinder may have other shapes and sizes (not shown) FIG. 4 shows the second platen 48 moved downwardly such that the platens press the connector plates into opposing surfaces of the structural members 38 .
The cylinder 53 is interconnected to the hydraulic power unit 32 by conventional hydraulic fluid lines 60 for providing hydraulic fluid under pressure to forcibly move the second platen 48 toward and away from the first platen 46 . A protective guard 62 is provided over the frontmost hydraulic fluid line 60 and its attachment to the cylinder 53 . Conventional pistol grip handles 64 are provided on opposite sides of the frame 44 so as to enable an operator readily to control the movement and operation of the press. Push button electrical switches 66 are mounted on the handles 64 for movement of the carriage 20 along the overhead rail 16 . Additional push button electrical switches 68 are provided on the handles for controlling operation of the platens of the press 12 . Other arrangements, shapes, number and orientations of the platens, including configurations where all platens are movable, and other power sources (i.e., non-hydraulic) do not depart from the scope of this invention.
The frame 44 includes a central (or third) portion 70 , shown in section in FIG. 8 , which has a generally C-shape and a uniform width. The central portion 70 is laterally bounded by two side plates 72 ( FIG. 2 ) attached to the central portion. Referring to FIGS. 8 and 9 , the frame 44 is adapted to inhibit fatigue damage. The frame has an inner peripheral load carrying surface 74 and an outer peripheral load carrying surface 76 which each have a shape that is smooth and free from discontinuity (i.e., generally no sharp or distinct localized bends in slope). Preferably the shapes generally define arcs, and more preferably segments of circles, such as semicircles, having noncoincident centers 78 . The arcs each have a rate of change of slope which ideally is close to a constant value along the extent of the respective load carrying surface 74 , 76 . That avoids discontinuity and stress concentration. Moreover, the central portion 70 of the frame and its arcs are free of any straight sections. Accordingly, there are no tight bends defining corners in which stress concentrations occur. Forces applied to the frame 44 while the platens 46 , 48 are pressing the connector plates are transmitted in loadpaths through the inner load carrying surface 74 and outer load carrying surface 76 which do not produce appreciable concentrations in stress beyond a nominal stress. Other smooth but non-circular shapes do not depart from the scope of this invention, nor do frames with only one peripheral load carrying surface having a shape free from discontinuity.
The frame 44 has an inner structural rim 80 ( FIG. 8 ) having a generally uniform thickness and which defines the inner peripheral load carrying surface 74 . Similarly, an outer structural rim 82 has a generally uniform thickness (less than the inner rim) and defines the outer peripheral load carrying surface 76 . The inner rim 80 is generally semicircular, but the outer rim 82 extends to a greater angular extent on the lower side of the frame 44 such that the outer rim forms a chin 84 for supporting the second platen 48 . The centers 78 are noncoincident, with an upper region of the frame 44 being generally thicker than the lower region, because stress levels are generally greater in the upper. A central web 86 ( FIG. 9 ) is positioned between the inner and outer rims 80 , 82 at the chin 84 and is oriented generally vertically. A shoulder 88 is provided for engagement by the actuator mount 58 , as discussed below.
Internal ribs 90 (collectively, “ribbing”) span and connect the inner and outer rims 80 , 82 for strengthening the frame 44 and distributing load. As seen in FIG. 8 , the ribs 90 are arranged in a triangular web pattern between the inner and outer rims. In this way, the frame itself becomes a truss for resisting applied loads, with the ribs 90 not only rigidifying the inner and outer rims 80 , 82 but transferring loads between them. The ribs facilitate a more efficient distribution of load between the inner and outer rims. In use, the frame 44 of this invention has permitted application of double the pressing load (from 25 tons to 50 tons) without increasing size or weight of the frame and without formation of fatigue cracks after repeated use. The ribs 90 have thicknesses which are large enough to transmit loads and minimize sharp edges at triangle corner radii, while small enough to avoid substantial weight penalty. Preferably, all the ribs 90 have a uniform thickness, such as ⅜ inch, although the thicknesses may vary depending on design loads. Further, the number and arrangement of ribs which extend between the inner and outer rims may vary without departing from the scope of this invention.
The inner rim 80 , outer rim 82 , ribs 90 , and central web 86 are preferably formed as one piece (comprising the central portion 70 of the frame), such as a one piece casting. That minimizes manufacturing cost and improves structural integrity. The frame 44 is formed of a suitable strong material, such as ASTM A148 steel. Frames which are formed with more than one piece or from other materials do not depart from the scope of this invention.
The frame 44 includes a foot 92 for supporting the frame in an upright position when it is lowered to a floor. Two guide bars 94 ( FIGS. 3 and 5 ) extend from the second platen 48 on opposite sides of the frame for preventing rotation of the cylinder 54 and second platen relative to the frame. The guide bars 94 are mounted in a cantilever arrangement with an end portion of each guide bar engaging a slide pad 96 which is fixedly mounted on the frame 44 . As the second platen 48 moves up and down relative to the frame, the end portion of each guide bar 94 also moves and slides along the respective pad 96 . The engagement prevents rotation of the cylinder and platen.
The actuator mount 58 is attached to the central portion 70 of the frame 44 and configured for mounting the cylinder body 56 . Referring to FIGS. 10-12 , the mount 58 includes a platform 98 and two sloping sidewalls 100 attached to the platform and forming lateral sides of the mount. The platform 98 has a counterbored hole 102 therein adapted for receiving the cylinder rod 54 and forming a seat for the cylinder body 56 . The platform 98 is configured for stable engagement with the shoulder 88 of the frame, as seen in FIG. 13 , and the sidewalls 100 are fixedly attached to the side plates 72 of the frame, as by welding. The press 12 is suspended by attaching the sidewalls 100 to the yoke 28 at pivots 104 ( FIGS. 2 and 3 ) which are located at a position generally aligned with a center of gravity so that the frame is maintained at a desired orientation.
The mount 58 is configured such that the cylinder 53 and its body 56 are removably attachable for rapid repair and maintenance. Upper and lower cylinder blocks 106 ( FIG. 2 ) are provided for holding the body 56 on the actuator mount 58 . Four connecting rods 108 interconnect the upper and lower blocks 106 . Each rod 108 is received through the upper block and is threaded on an upper end for receiving a cap nut 110 . Each rod 108 is threaded on a lower end for being received in a threaded hole (not shown) on the lower block. Bolt fasteners 112 ( FIG. 2 ) hold the assembled blocks 106 and body 56 to the mount 58 . The fasteners 112 extend through the lower block 106 and are received in threaded holes 114 ( FIG. 10 ) positioned on the platform 98 . A differently sized cylinder 53 may be substituted for applying a larger or smaller load, or a malfunctioning cylinder may be replaced, by unfastening the blocks 106 from the mount, detaching the hydraulic lines 60 , and installing a new body 56 . There are no welds or fixed attachment which must be broken, and downtime is minimized. The cylinder and its tubular body are therefore “off the shelf” replaceable units. Other attachable/detachable mounting configurations of the cylinder do not depart from the scope of this invention.
The second platen 48 is designed for strength for applying relatively greater forces, such as 50 tons. Referring to FIGS. 5-7 , the platen 48 has a bottom side 116 , comprising its front side, for engaging the connector plate 40 and a top side 118 , comprising its back side. A boss 120 extends from the top side 118 for receiving the cylinder rod 54 . A conventional coupler 122 having a collar and a ring of axial fasteners attach the cylinder rod 54 to the second platen 48 . Four gussets 124 are in spaced arrangement on the top side 118 of the second platen, extending at an inclined angle between the boss 120 and the top side for providing added strength and stability. Each gusset 124 slopes in height from a maximum height near a top of the boss 120 to the surface of the top side 118 . Preferably, the second platen 48 , boss 120 , and gussets 124 are formed in one piece. The gussets 124 inhibit deflections of the second platen 48 and do so without increasing thickness of the platen which would increase weight and cost. When the platen 48 inadvertently presses a non-flat object, such as due to operator error, the load is not distributed across the platen but rather is concentrated at one, usually eccentric location on the platen. The gussets 124 inhibit deflection and failure by transmitting the concentrated load to the boss 120 and more effectively distributing the load until the operator releases the press. Other configurations, such as a different size, number, or configuration of gusset(s), do not depart from the scope of this invention. Further, similar gussets could be included on the first platen 46 .
The apparatus of the present invention includes a timer and controller unit 126 , indicated schematically in FIG. 14 , for operational efficiency. The unit 126 is part of the control unit 34 shown in FIG. 1 , and it is adapted to automatically hold the cylinder rod 54 at a preselected force for a preselected period of time. The timer and controller unit 126 is selectively adjustable for selecting the force and time period. Typically, the preselected force is a maximum force which is to be applied by the press 12 and the time period is sufficient for completely embedding the connector plates 40 in the structural members 38 . The time period, also known as “dwell time” to those skilled in the art, is an automated hold at the selected maximum force to permit the fasteners on the connector plates 40 to more fully embed in pre-cut timbers. A typical period is 3 seconds. When the operator presses the push button electrical switches 68 , the hydraulic power unit 32 is activated to move the cylinder rod 54 and second platen 48 and press the connector plates 40 into the structural members 38 . When the applied force reaches the preselected or maximum force, as measured by conventional sensors (not shown), the power unit holds the force relatively constant for the preselected dwell time before beginning release. The automation of the timer permits a more exact and repeatable process which avoids delays of manual inspection/estimation and repetitive cycles of force application.
In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results obtained.
When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
As various changes could be made in the above without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | A press apparatus for pressing connector plates into opposing surfaces of structural members which are to be secured together to form a structure such as a roof truss. The apparatus includes a frame particularly constructed to reduce stress concentrations and failure. Forces applied to the frame are transmitted in a loadpath which is smooth and free from discontinuity to inhibit concentration of stress and thereby strengthen the frame against fatigue damage. The frame includes ribs spanning and connecting an inner rim and outer rim for strengthening the frame. A powered actuator has a body which is removably attachable to the frame, and a timer control operates the press to make sure the connector plates are fully embedded. | 8 |
This invention relates to a method and apparatus for controlling the gap between the bottom of an electrode and the top surface of an ingot in a consumable electrode furnace. More particularly, this invention relates to controlling this gap by controlling electrode drive speed as a function of electrode drive base speed (S B ) as algerbraically modified by the trim speed (S T ). Base speed (S B ) is determined from the melt rate and the known geometry of the electrode and the crucible together with measured changes in the electrode or ingot weight as the melt proceeds. Trim speed (S T ) is determined by a relative by slow acting control loop using voltage discontinuities as a feedback signal. Thus, electrode drive speed may be adjusted during a melt according to the equation
S=f(S.sub.B, S.sub.T)
for example:
S=S.sub.B +S.sub.T
BACKGROUND OF THE INVENTION
The proper positioning of the electrode is a critical element in the operation of a consumable electrode furnace, for example a vacuum arc furnace. The operation of a vacuum arc furnace depends upon the control of the arc length or the arc gap which is the distance between the bottom of the electrode and the surface of the pool of molten metal at the top of the ingot. The quality of an ingot formed in such a furnace depends upon the maintenance of a consistent arc length which can be neither to short nor too long.
The problem of maintaining the proper arc length has been dealt with in various ways by furnace manufacturers and users. Initially, the voltage gradient across the gap was used but this proved to be inadequate. Subsequently it was discovered that the frequency and/or duration of periodic fluctuations in the arc voltage signal could be used to improve control of arc length throughout the vacuum arc electrode melting procedure. Several patents have elaborated upon the necessity of controlling the electrode position so as to maintain a predetermined arc length throughout the melt procedure, and on the difficulties that are found in attempting to do this. See, for example, U.S. Pat. Nos. 2,942,045; 2,904,718; 3,372,224; 3,187,078 and 3,186,043. Some of these patents, such as U.S. Pat. Nos. 2,942,045 and 3,187,078, disclose the use of the frequency and/or duration of periodic fluctuations in the arc voltage signal, either alone (U.S. Pat. No. 2,942,045) or in combination with the arc voltage signal (U.S. Pat. No. 3,187,078) as an indication of arc length.
The operation of a consumable electrode furnace is a dynamic process. The electrode is being consumed and therefore must be lowered to compensate for its shortened length. The ingot is of course being formed within the crucible and therefore the rate at which its surface rises affects the speed at which the electrode is lowered toward that surface. The electrode drive means is therefore traditionally set to adjust the electrode feed rate to maintain constant arc length using the frequency and/or duration of periodic fluctuations in the arc voltage as a feedback signal indicative of arc length.
A fundamental problem with arc length regulating systems of this type is that the periodic fluctuations in arc voltage, while having a long term average relationship to arc length, also have a short term random component. Accurate determination of arc length requires that measurements be made of the average frequency and/or duration of fluctuations in the arc voltage signal over a sufficiently long period of time for the random fluctuations to average out to zero.
This creates a dilemma in the design of the arc length control system. If the control system is made responsive and relatively fast acting, it also responds to short term random components in the feedback signal, which in turn leads to ranrandom short term fluctuation of the arc length that can have severe deleterious effects upon the ingot quality. If the control system is made less responsive, it cannot generate the relatively rapid changes in electrode drive speed which are required when the melt rate is changed rapidly as often the case at the beginning and the end of a melt. In this latter case the lag in response of the electrode control system leads to excessively long arc lengths when the melt rate is increasing and to excessively short arc lengths when the melt rate is decreasing.
The existence of the above problem is acknowledged in U.S. Pat. No. 2,942,045 at column 8, line 61 through column 9, line 27, and is touched upon in U.S. Pat. No. 3,187,078 at column 3, lines 11 and 12. Both of these patents disclose control systems which take the second of the two design approaches mentioned above; i.e. the arc length control system is made slow acting by incorporating electrical or electromechanical integrators having long time constants in the control loop.
Analagous problems exist in other types of consumable electrode furnaces such as electroslag remelting (ESR) furnaces. Conventionally the electrode drive speed is based upon measurement of current flow through the slag both or the voltage across it. As in the cae of the vacuum arc furnace, such electrical measurements are subject to undesirable short term or random disturbances. For example, the voltge may drop during start up of another piece of machinery connected to the same electrical power distribution network which is supplying electrical power to the ESR furnace. It would be undesirable for the electrode drive to respond to such a disturbance.
SUMMARY OF THE INVENTION
This invention provides a control system which eliminates the aforesaid disadvantages of having to choose between either an overly responsive or less responsive control system for controlling electrode speed during a melt and therefore provide consisent maintenance of the gap between the bottom of an electrode and the upper surface of an ingot. In accordance with this invention, the control system for electrode drive speed is based upon a combination of two signals herein denominated as base speed (S B ) and trim speed (S T ) which may be stated by the following equation:
S=S.sub.B +S.sub.T (equation 1)
S=electrode drive speed
S B =base speed
S T =trim speed
Equation 1 permits the control system to respond to rapid changes in melt rate with immediate variations in the base speed. However, the errors inherent in controlling electrode drive speed solely by base speed are compensated by the trim speed. More particularly, base speed is calculated from the melt rate and the known geometry of the electrode and the crucible together with the measured change in electrode or ingot weight as the melt proceeds. Trim speed is determined by a relatively slow acting control loop using electrical parameters such as volt discontinuities as a feedback signal. Although Equation 1 is written as an algerbraic sum, it is within the scope of this invention that S T modify S B by mathematical minipulation other than summation.
Thus, the present invention provides an electrode drive speed control system for a consumable electrode furnace which regulates the electrode drive speed at a base speed computed from measured changes in physical characteristics of electrode or ingot, such as changes in weight, as the melt proceeds, the known geometry of the electrode, the crucible, density of the ingot material, and the speed of movement of the bottom of the ingot (if any) with such base speed being increased or decreased by a trim speed determined from measurements of electrical phenomenon associated with the consumable electrode process, which electrical phenomenon having relatively long term value related to the distance between the bottom surface of the electrode and the top surface of the ingot. In a vacuum arc furnace the chosen electrical phenomenon may be the frequency and/or duration of periodic fluctuations in the arc voltage signal. In an electroslag furnace the chosen electrical phenomenon may be the magnitude of the voltage across the slag bath or the magnitude of the current through it.
For the purpose of illustrating the invention, there is shown in the drawing a form which is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic block diagram of a control system for controlling electrode drive speed in a consumable electrode furnace.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawing in detail, wherein like numerals indicate like elements, there is shown a schematic drawing of a closed loop control system for a vacuum arc furnace 10. Although the invention is described in relation to a vacuum arc furnace, it should be understood that this is by way of example, not limitation, and the invention is also applicable to the operation of other consumable electrode furnaces including electroslag furnaces.
As shown, the vacuum arc furnace 10 includes an ingot mold defined by a water cooled crucible 12 positioned on a water cooled stool 14. A vacuum is maintained within the crucible 12 by evacuating equipment (not shown) connected to the pipe 16 in head 17.
The electrode 18 is supported within the furnace 10 by the clamp 20 at the end of ram 21. Ram 21 extends through an appropriate vacuum seal 22 in the top wall of the furnace 10. Clamp 20 includes the load cell 24. Ram 21 in turn is connected to an electrode support screw 26 which rotates within nut 28. Electrode support screw 26 is rotated by the electrode drive motor 30 and gearing 31.
Power to operate the furnace 10 is provided by the direct current power supply 32.
The vacuum arc furnace 10 per se is known to those skilled in the art as exemplified by U.S. Pat. Nos. 2,726,278 and 3,246,070. Accordingly, a more detailed description of its function and operation need not be provided.
The furnace 10 is shown in mid melt with an ingot 34 partially formed in the crucible 12. A pool of molten metal 36 on the top of ingot 34 is formed as fused droplets of metal fall from the electrode 18. It is believed that it is the molten droplets or the splash which they create within the pool of molten metal that creates the voltage discontinuities.
The electrode drive motor 30 turns the electrode drive screw 26 and hence lowers the electrode 18 toward the ingot 34. The speed at which it lowers the electrode is determined by the control system hereinafter described.
As noted above electrode drive speed S is a function of base speed S B andd trim speed S T ; i.e.
S=f(S.sub.B, S.sub.T)
It has also been indicated that electrode drive speed S in accordance with the foregoing function may be determined by the following equation:
S=S.sub.B +S.sub.T (1)
Where:
S=electrode drive speed
S B =base speed
S T =trim speed
Base speed S B is determined by a control system which solves the following two equations. ##EQU1## Where: π≅3.1416
B=average electrode density
We=initial electrode weight
De=electrode diameter
Le=initial electrode length ##EQU2## where: π≅3.1416
S B =electrode base speed
M=melt rate calculated from the rate at which the electrode rate decreases or the ingot weight increases
De=electrode diameter
B=average electrode density
Di=ingot diameter
A=average ingot density
The derivation of equation 3 is as follows (using English units).
It is known that for a cylindrical ingot of diameter D I (inches), and density A (lbs per cubic inch), the axial length for 1 lb weight is given by: ##EQU3##
Similarly for an electrode of diameter D e (inches) and density B (lbs per cubic inch) the length for 1 lb weight is: ##EQU4##
If the base of the ingot is stationary and the arc length is to be kept constant, the electrode must be lowered an amount equal to the difference between the electrode length and the ingot length.
Therefore for each pound melted the electrode must be lowered a distance T 1 inches given by: ##EQU5##
Therefore for M pounds melted the travel (T M ) is ##EQU6##
If M pounds are melted in 1 hour (i.e. a melt rate of M pounds per hour) then the electrode is lowered at T M inches per hour, to maintain constant arc length.
The foregoing equations are based upon the assumption that the electrode and crucible are approximately cylindrical. Crucibles are usually slightly tapered and electrodes are often tapered as well. Moreover, both the electrode and crucible may have non-circular cross sections. However, such variations may readily be accomodated by modification of the above calculations.
The electrode diameter and length are readily measured prior to the start of a melt. The electrode weight is measured at the start and at regular intervals during the melt. These initial measurements readily provide electrode density.
Ingot density is known from prior experience as is the average diameter of the ingot which is formed in a crucible of known diameter.
The determination of average electrode density (B) is made once at the start of the melt to establish the average value of B to be used throughout the entire melt.
Calculation of melt rate M and base speed S B are made at frequent intervals throughout the melt to determine a new value of speed at which the electrode is to be driven. Accordingly, base speed (S B ) will vary in accordance with required changes in the melt rate (M). The melt rate is the weight per unit of time at which the electrode is fused into molten metal. As described in U.S. Pat. No. 4,131,754, a melt rate signal can be calculated and used as a feedback signal in an automatic melt rate control system for the power supply. The melt rate control system of U.S. Pat. No. 4,131,754 is referred to and incorporated herein by such reference.
By way of example, not limitation, melt rate M can be calculated as described in "A System for the Automatic Measurement and Control of Melt Rate During Electroslag Remelting" by Raymond J. Roberts, published in the proceedings of the Fifth International Symposium on Electroslag and Other Special Melting Technologies on Oct. 16-18, 1974 in Pittsburgh, Pa.
Trim speed (S T ) can be determined in a number of ways, depending upon whether the control system is to be based upon the frequency, duration or both frequency and duration of the fluctuations in the arc voltage signal. In the following explanation, it is assumed that control of trim speed is to be based upon the frequency of occurence of voltage variations caused by droplets of metal which bridge the arc gap. This drip short phenomenon is described in U.S. Pat. No. 2,942,045.
The control system uses this phenomenon to compute trim speed S T by measuring the time interval between successive drip shorts, and calculating the average time between a predetermined number of the most recent drip shorts. By way of example, it may calculate the time interval between the ten (10) most recent shorts. However, that the number may adjusted upward or downward depending upon experience and may vary depending upon crucible size and metal alloy.
This average time is then compared with a set point average to determine trim speed as follows:
S.sub.T =K.sub.1 e+K.sub.2 ∫edt+K.sub.3 de/dt (equation 4)
where:
e=T a -T sp error between average time between drip and set point time between drip shorts
T a =the average time between the predetermined number of the most recent drip shorts
T sp =set point average time between drip shorts
S T =electrode drive trim speed
K 1 =proportional constant
K 2 =integral constant
K 3 =rate constant
K 1 , K 2 and K 3 , are the constants for the standard three term control equation widely used in closed loop control processes. As used in accordance with the control system of the present invention, K 1 and K 3 should be made small relative to K 2 so that the integral term becomes dominant in Equation 4. Further, K 2 should itself be made sufficiently small that a relatively long time is required for S T to make appreciable changes in total speed.
T sp may be a constant for a particular arc length and material, or may itself be a variable which has a known relationship to current level and/or vacuum level at a particular arc length.
The value of base speed (S B ) and trim speed (S T ) is recomputed frequently during a melt, and the electrode drive speed adjusted according to Equation 1. Since the melt rate (M) in Equation 3 is always zero or positive, and since the electrode diameter is always smaller than the ingot diameter and the density of the electrode is always equal to, or smaller than the ingot density, the value (S B ) computed in Equation 3 will be zero or some positive value.
The trim speed (S T ) computed in Equation 4 may be positive or negative, and will act to increase or decrease the drive speed relative to the base speed. Thus, the trim speed (S T ) compensates for any inaccuracies in the value used to compute the base speed (S B ); that is, the value on the right hand side of Equation 1.
Equation 4 relates to a determination of S T in a control system. However, examination of the equation shows that the controlling variable for a vacuum arc furnace is T a . Thus, a more general function for the electrode drive speed in a vacuum arc furnace can be derived. Thus,
S=f(S B , S T )
S T =f(T a -T sp )
T sp is a constant
S=f(S B , T a )
Where:
S=electrode drive speed
S B =base speed
T a =a quantity based upon statistical analysis of the frequency and/or duration of drip shorts
The advantage of controlling the gap between the lower end of an electrode and the top surface of a ingot using electrode drive speed based upon a combination of base speed and trim speed can now be better appreciated. Rapid changes in the melt rate will result in immediate variation in base speed (S B ). This enables the electrode drive to track such variations accurately. However, if this system alone were used to control the electrode drive, inevitably minor inaccuracies of measurement or in assumptions made in respect to the various parameters on the right side of the equality side of Equation 3 may result in a slow cumulative buildup error in the value of the arc length. However, such a slow buildup is compensated by the trim speed (S T ) function which is calculated based upon the observation of the arc voltage signals taken over a sufficiently long time that random fluctuations can be eliminated by averaging or other statistical minipulation.
It is not intended that the modification of base speed by a trim speed function be limited to the algebraic addition described above. For example the error value calculated as per Equation 4 could be used to conpute a multiplying factor by which the base speed is adjusted. In this system an error value of zero would result in a multiplying factor of unity i.e. the electrode would be driven at base speed. A positive error value (resulting from an arc length which is too long) would result in a multiplying factor greater than unity i.e. the electrode drive speed would be higher than base speed, so as to decrease the arc length towards the desired value. Conversely a negative error would result in a multiplying factor of less than unity so as to decrease the drive speed and thereby increase the arc length toward the desired value.
The foregoing determination of electrode drive speed assumes that the bottom of the ingot 34 is stationary. Nonstationary ingots, such as are used in an ingot withdrawl vacuum arc remelting system, can be accomodated by an extension of the control equations. If the base of the ingot is withdrawn at a speed (S T ), then this amount must be added to the electrode drive speed:
S=S.sub.B +S.sub.T +S.sub.I (equation 5)
A control system which provides electrode drive speed in accordance with Equation 1 is shown in FIG. 1.
The speed at which the electrode 18 is lowered within the crucible 12 is directly proportional to the rate at which screw 26 is rotated by electrode drive motor 30. Accordingly, electrode drive motor 30 is provided with a tachometer 40 whose output signal is proportional to the speed of motor 30. Motor 30 is a variable speed electric motor such as the motor 34 shown in U.S. Pat. No. 2,726,278.
Load cell 24 provides a signal which is proportional to electrode weight. This signal is fed to electrode weight indicator 42. Load cell 24 may be any one of several types of devices used to measure the weight of an electrode as it is being melted. It can be either an hydraulic or strain gauge type as desired. By way of example, the load cell 24 may be of the type described in U.S. Pat. No. 3,272,905. Load cell 24 may be positioned outside the furnace.
Electrode weight indicator 42 provides exitation for the load cell 24, if required, and converts the output signal of load cell 24 into a weight signal. Suitable electrode weight indicators are available from several sources, including BLH Electronics of Waltham, Mass.
Electrode weight indicator 42 feeds an electric signal proportional to electrode weight to the computing system 44. Computing system 44 may be either an analog or digital computer. Preferably it is either a minicomputer, microcomputer or programmable calculator provided with appropriate interface circuitry for receiving and sending analog and/or digital signals from and to the various circuits described herein. Suitable computing systems are available from Data General, Inc., Digital Equipment Corporation and others.
An arc voltage signal is detected by arc voltage circuit 46 and provided as an input to the computing system 44. The computing system receives the arc voltage signal and determines the error e between the average time between a predetermined number of the most recent drip shorts T a and the set point average time between drip shorts T sp .
For an electroslag furnace, the computing system compares variations in the magnitude of the voltage across the slag bath or variations in the magnitude of the current through the slag bath to a set point voltage or current to provide the error signal for calculating S T in Equation 4. In addition, computing system 44 receives operator supplied input data from data terminal 48. This may be provided by any one of a keyboard/printer, CRT terminal or card or paper tape reader as is well known in the computer art. Suitable terminals, keyboards or the like are available from Texas Instruments, Lear Seagler, Hazeltine or others. If an analog computing system is used, then the data may be inputted using potentiometers.
Amplifier 50 provides a drive signal to motor 30 in response to the electrode drive speed signal S provided by the computing system 44. Amplifier 50 may be a magnetic amplifier, thyristor or transistor type of motor speed controller. Suitable motor speed controllers may be acquired from Westinghouse Electric Corporation, General Electric Corporation and others. Such motor speed controllers detect the actual speed of motor 30 based upon the signal received from tachometer 40 and adjust that speed to the desired electrode drive speed S.
From the foregoing, it should be apparent that the computing system 44 is provided with all of the information necessary to solve Equation 1. Electrode weight is continuously provided by electrode weight indicator 42 and the arc voltage signal is continuously provided by arc voltage circuit 46. All other data as well as updates on such data are provided by the operator terminal 48. It should be noted that the system works equally well by continuously measuring ingot weight rather than electrode weight.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingle, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the invention. | A method and apparatus for controlling electrode drive speed in a consumable electrode furnace. The electrode drive speed is regulated at a base speed computed from measured changes in physical characteristics of the electrode or ingot, such as changes in weight, as the melt proceeds. The base speed also takes into consideration the known geometry of the electrode, the furnace mold or crucible, the density of the ingot material, and the speed of movement of the bottom of the ingot if any. This base speed is increased or decreased by a trim speed determined from measurement of an electrical phenomenon associated with the consumable electrode process, which electrical phenomenon has a relatively long term value related to the distance between the bottom surface of the electrode and the top surface of the ingot. | 8 |
FIELD OF THE INVENTION
The present invention relates to a process for making a particulate detergent composition exhibiting improved solubility. More specifically, the process comprises spraying nonionic surfactant, in liquid form, onto relatively hot spray-dried granules, cooling the granules and mixing the granules.
BACKGROUND OF THE INVENTION
A main concern over the years for detergent manufacturers has been providing detergent compositions which exhibit good solubility in various wash water conditions. This concern has particularly become important in the field recently with the proliferation of higher density "compact" detergents, i.e., detergent compositions having bulk densities of 600 g/l or higher. Poor solubility of a detergent composition may result in, e.g., clumps of detergent which appear as solid white masses remaining in the washing machine and/or on washed clothes. In particular, such clumps can occur in cold wash water conditions and/or when the order of addition to the washing machine is laundry detergent first, clothes second, and water last.
The various approaches detergent manufacturers have taken to improve the solubility of detergent compositions include: (a) compacting spray-dried granules at low pressures (20 to 200 psi) and granulating the resulting compacted material; (b) combining at least two multi-ingredient components, one being spray-dried and containing slower-dissolving detergent surfactant, the other being agglomerated and containing a faster-solubilizing detergent surfactant; and (c) incorporating admixed hydrophobic amorphous silicate material into a sodium carbonate-containing detergent, bleach, or additive composition.
The prior art discloses spraying nonionic surfactant over the surfaces of spray-dried base detergent beads, but fails to disclose the desirability and/or the practicality of combining the incorporation of nonionic into a spray-dried granule while the granule is relatively hot in combination with cooling and mixing steps. It would be desirable to have detergent granules that exhibit improved solubility and are more crisp and free-flowing than the aforementioned prior art granules.
Therefore, despite the aforementioned disclosures in the art, there remains a need for a process which provides a detergent composition having improved solubility. There is also a need for such a process which provides a detergent composition which has improved flow properties in that it is more crisp and free-flowing.
BACKGROUND ART
The following references relate to detergent granules, the solubility thereof and/or the flow properties of such granules: U.S. Pat. No. 4,715,979 (Moore et al); U.S. Pat. No. 5,009,804 (Clayton et al); WO 93 14182 (Morgan et al); U.S. Pat. No. 3,838,072 (Smith et al); U.S. Pat. No. 3,849,327 (DiSalvo et al); U.S. Pat. No. 4,006,110 (Kenny et al); U.S. Pat. No. 5,149,455 (Jacobs et al); and U.S. Pat. No. 4,637,891 (Delwel et al). U.S. Pat. No. 5,366,652 (Capeci et al) relates to making detergent agglomerates.
SUMMARY OF THE INVENTION
The instant invention meets the needs identified above by providing a process which produces a detergent composition that exhibits improved solubility as well as improved flow properties. The improved solubility can be detected by evidence of increased solubility of the surfactants in the washing solution and/or by the decreased amount of detergent residue left on laundered clothes. It has now been discovered that incorporating nonionic surfactant on and/or in spray-dried detergent granules before cooling the granules and while they are relatively hot, and thereafter cooling and mixing the granules improves the solubility and flow properties of the granules. All percentages, ratios and proportions used herein are by weight, unless otherwise specified. All documents including patents and publications cited herein are incorporated herein by reference.
In accordance with one aspect of the invention, a process for producing a free-flowing, particulate detergent composition having improved solubility is provided. The process comprises the steps of: A) spray drying an aqueous slurry containing an anionic surfactant and a detersive builder so as to form spray dried granules having a temperature in a range of from about 80° C. to about 120° C.; B) spraying a nonionic surfactant in substantially liquid form on said spray dried granules while said spray dried granules have a temperature within said range; C) cooling spray dried granules to a temperature between about 40° C. and about 70° C.; and D) mixing said spray dried granules to improve the flow properties thereof, thereby resulting in the formation of said detergent composition.
In accordance with another aspect of the invention, another process for preparing a free-flowing, particulate detergent composition having improved solubility is provided. The process comprises the steps of: A) spray drying an aqueous slurry containing an anionic surfactant and a detersive builder so as to form spray dried granules having a temperature in a range of from about 80° C. to about 120° C.; B) spraying a nonionic surfactant in substantially liquid form on said spray dried granules while said spray dried granules have a temperature within said range; C) cooling spray dried granules to a temperature between about 40° C. and about 70° C.; and D) grinding said spray dried granules such that said spray dried granules have a mean particle size of from about 300 microns to about 600 microns, thereby resulting in the formation of said detergent composition.
Also provided is the free-flowing, particulate detergent compositions produced according to the process inventions described herein.
Accordingly, it is an object of the invention to a process which provides a detergent composition having improved solubility. It is an object of the invention to provide a process which provides a detergent composition which has improved flow properties in that it is more crisp and free-flowing. These and other objects, features and attendant advantages of the present invention will become apparent to those skilled in the art from a reading of the following detailed description of the preferred embodiment and the appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The process for making the detergent composition herein generally comprises spray drying an aqueous slurry containing an anionic surfactant and a builder into spray dried granules, spraying a nonionic surfactant on the spray-dried granules followed by cooling and mixing the granules. The various essential and adjunct detergent ingredients and equipment used in the process are described in detail below.
The Process
The spray dried granules which are formed in step A of the process herein are prepared according to known processes for spray-drying aqueous mixtures. Such processes include spray drying conventional detergent ingredients, e.g., detergent surfactants and detergency builders, to form spray dried granules, typically in relatively tall spray drying towers. The spray drying step of the process preferably includes dispersing an aqueous slurry or mixture under high pressure through nozzles down a spray drying tower through which hot gases are counter-currently flowing up the tower. This process step can be carried out in conventional spray drying equipment such as the aforementioned towers as well as other spray drying apparatus.
Preferably, the resulting spray dried granules formed in the spray drying apparatus have a temperature from about 80° C. to about 120° C., and more preferably from about 80° C. to about 105° C. While not intending to be bound by theory, it is believed that the anionic surfactant in the spray dried granules is in a more "liquid" crystalline state when compared to the anionic surfactant in the granules after cooling which is in a more "structured" crystalline state. The "liquid" crystalline anionic surfactant state allows the nonionic surfactant to penetrate into the spray dried granule better than the "structured" crystalline anionic surfactant found in spray dried granules after cooling. The higher temperature itself of the spray dried granule also promotes greater penetration of nonionic surfactant. As a consequence of the penetration and complete nonionic coating of the granules while they are at a relatively hot temperature, the solubility of the composition is improved in the washing solution.
Preferably, the aqueous slurry used to produce the spray dried granules formed in step A of the process comprise the anionic surfactant, the builder and no more than about 1.0%, preferably 0%, by weight of nonionic surfactant. The amount of nonionic in the aqueous slurry is based on limitations concerning environmental and safety concerns (plume opacity, auto-oxidation) and limitations concerning the physical properties of the slurry used during the spray drying process step, i.e., step A.
In the second step of the process herein, step B, nonionic surfactant is incorporated into spray-dried detergent granules by spraying the nonionic while it is substantially in the liquid state. To facilitate that end, the nonionic surfactant preferably has a melting point between about 25° C. and about 60° C., and is preferably heated to between about 25° C. and about 105° C., more preferably between 60° C. and 95° C. As the spray dried granules exit a spray drying tower, the anionic surfactant in the granules is in a predominantly liquid crystalline state which allows for better penetration of the nonionic surfactant into the granules. After cooling of the spray dried granules, the anionic surfactant is in a more structured crystalline state which does not lend itself as well to penetration of the nonionic as does the liquid crystal state. The physical properties of the detergent granules after cooling also limits the amount of nonionic that can be incorporated after cooling of the granules, e.g., there is a significant decrease in the flowability of the granules after cooling. At or near the exit of the spry drying tower, the nonionic surfactant is sprayed onto the granules. The amount of nonionic surfactant is from about 5% to about 20%, preferably from about 1% to about 5%, and most preferably from about 1% to about 2%, by weight of the overall detergent composition.
Conventional methods and equipment can be used in step B to spray the nonionic surfactant on the granules so long as they provide sufficient liquid-to-solid particle contact to incorporate the nonionic surfactant into the spray dried granules sufficiently. Such methods include one- or two-fluid nozzle arm positioned horizontally or vertically into a baffled or un-baffled mix drum, single or two-fluid nozzle system spraying onto a horizontal conveyor belt, into a bucket elevator system, into a gravity-fed product chute, or onto a screw conveyor and any other device which provides suitable means of liquid spray-on and preferably agitation. The apparatus may be designed or adapted for either continuous or batch operation as long as the essential process steps can be achieved. Examples of agitation equipment that is preferably used in this step include Lodige KM mixer, a V-blender, an inclined tumbling drum, or a bel; or screw conveyor.
Once the spray dried granules have been sprayed with nonionic surfactant, the granules are cooled in step C to a temperature from about 15° C. to about 40° C., preferably from about 20° C. to about 35° C., more preferably from about 25° C. to about 30° C. Preferably, this cooling step is conducted in an airlift apparatus which provides from about 0.1 to 1 minutes residence time, more preferably from about 0.8 to about 0.9 minutes residence time. While not intending to bound by theory, it is believed that the residence time is required to allow for the penetration of the nonionic surfactant applied earlier into the detergent granule and for the granule to cool and form a more structured crystalline particle. Other conventional apparatus and methods which provide cooling capacity sufficient to cool the detergent granules can be used. Such apparatus include fluid bed coolers, vented tumbling drum, vented belt conveyor, or vented chute work. The residence time in such apparatus will vary, for example, use of a fluid bed cooler to cool the granules involve residence times on the order of from about 5 minutes to about 20 minutes.
The next step in the instant process comprises mixing the cooled granules to enhance the flow properties of the composition in which the granules are contained. Preferably, the mixing step will include the step of grinding the granules, wherein the mean particle size of the granules is reduced to from about 300 microns to about 600 microns, more preferably from about 400 microns to about 500 microns. As used herein "grinding" comprises any method which results in decreasing the mean particle size of the cooled granules such that substantially spherical, uniform granules are formed. Methods of grinding particulate components are well-known to those skilled in the art. This process step reduces coarse granules, rounds off irregularly shaped granules and compacts "fines".
The mixing and/or grinding apparatus may be designed or adapted for either continuous or batch operation. Examples of such apparatus are described in, e.g., U.S. Pat. No. 5,149,455 (Jacobs et al); U.S. Pat. No. 5,133,924 (Appel et al); and EP Patent 351,937 (Hollingsworth et al), all incorporated herein by reference and include the Lodige CB mixer/densifiers, vertical agglomerators/mixers (preferably a continuous Schugi Flexomix or Bepex Turboflex), other agglomerators (e.g. Zig-Zag agglomerator, pan agglomerators, twin cone agglomerators, etc.) rotating drams, and any commercially available grinders or particle size reducers.
In a preferred embodiment of the process herein, from about 75% to about 90%, by weight of the overall detergent composition, of the nonionic surfactant is incorporated into the spray dried granules prepared in accordance with process steps described above. Optionally, a portion of this nonionic surfactant can be incorporated in the mixing step of the process herein.
Once the spray dried granules have been made in accordance with the process herein, the granules can be used as the detergent composition itself or optionally, other detergent components can be admixed to form the composition. Additionally, optional process steps include may be employed such as adding a coating agent to the spray dried granules for purposes of further enhancing the flow properties of the composition. Preferably, this is completed at any stage of the process after the cooling step. The coating agent is preferably selected from the group consisting of aluminosilicates, carbonates and mixtures thereof. Other optional process steps include particle size classification by screening, spray addition of liquid perfumes, liquid dyes, or other detergent components, including addition of more nonionic surfactant. mixing of the base granules with other dry detergent components and subsequent.
Detergent Surfactant
The detergent compositions produced by the process invention herein preferably comprise from about 5% to about 40%, more preferably from about 10% to about 35%, most preferably from about 15% to about 30%, by weight of the composition, of detergent surfactant. The detergent surfactant can be selected from the group consisting of anionics, nonionics, zwitterionics, ampholytics, cationics, and mixtures thereof. Preferred compositions comprise a detergent surfactant selected from the group consisting of anionics, nonionics and mixtures thereof. More specifically, the detergent compositions of the invention herein comprises from about 5% to about 35%, preferably from about 10% to about 30%, most preferably 15% to about 30%, by weight of anionic surfactant.
Water-soluble salts of the higher fatty acids, i.e., "soaps", are useful anionic surfactants in the compositions herein. This includes alkali metal soaps such as the sodium, potassium, ammonium, and alkylolammonium salts of higher fatty acids containing from about 8 to about 24 carbon atoms, and preferably from about 12 to about 18 carbon atoms. Soaps can be made by direct saponification of fats and oils or by the neutralization of free fatty acids. Particularly useful are the sodium and potassium salts of the mixtures of fatty acids derived from coconut oil and tallow, i.e., sodium or potassium tallow and coconut soap.
Useful anionic surfactants also include the water-soluble salts, preferably the alkali metal, ammonium and alkylolammonium salts, of organic sulfuric reaction products having in their molecular structure an alkyl group containing from about 10 to about 20 carbon atoms and a sulfonic acid or sulfuric acid ester group. (Included in the term "alkyl" is the alkyl portion of acyl groups.) Examples of this group of synthetic surfactants are the sodium and potassium alkyl sulfates, especially those obtained by sulfating the higher alcohols (C 12 -C 18 carbon atoms) such as those produced by reducing the glycerides of tallow or coconut oil; and the sodium and potassium alkylbenzene sulfonates in which the alkyl group contains from about 10 to about 16 carbon atoms, in straight chain or branched chain configuration, e.g., see U.S. Pat. Nos. 2,220,099 and 2,477,383. Especially valuable are linear straight chain alkylbenzene sulfonates in which the average number of carbon atoms in the alkyl group is from about 11 to 14, abbreviated as C 11-14 LAS.
Especially preferred are mixtures of C 11-16 (preferably C 11-13 ) linear alkylbenzene sulfonates and C 12-18 (preferably C 14-16 ) alkyl sulfates. These are preferably present in a weight ratio of between 4:1 and 1:4, preferably about 3:1 to 1:3, alkylbenzene sulfonate:alkyl sulfate. Sodium salts of the above are preferred.
Other anionic surfactants herein are the sodium alkyl glyceryl ether sulfonates, especially those ethers of higher alcohols derived from tallow and coconut oil; sodium coconut oil fatty acid monoglyceride sulfonates and sulfates; sodium or potassium salts of alkyl phenol ethylene oxide ether sulfates containing from about 1 to about 10 units of ethylene oxide per molecule and wherein the alkyl groups contain from about 8 to about 12 carbon atoms; and sodium or potassium salts of alkyl ethylene oxide ether sulfates containing about 1 to about 10 units of ethylene oxide per molecule and wherein the alkyl group contains from about 10 to about 20 carbon atoms.
Other useful anionic surfactants herein include the water-soluble salts of esters of alpha-sulfonated fatty acids containing from about 6 to 20 carbon atoms in the fatty acid group and from about 1 to 10 carbon atoms in the ester group; water-soluble salts of 2-acyloxyalkane-1-sulfonic acids containing from about 2 to 9 carbon atoms in the acyl group and from about 9 to about 23 carbon atoms in the alkane moiety; water-soluble salts of olefin and paraffin sulfonates containing from about 12 to 20 carbon atoms; and beta-alkyloxy alkane sulfonates containing from about 1 to 3 carbon atoms in the alkyl group and from about 8 to 20 carbon atoms in the alkane moiety.
The detergent compositions of the invention herein also comprise nonionic surfactant as described previously. Depending on the nonionic surfactant, the nonionic surfactant can be incorporated into the detergent composition as an integral part of the spray dried granule and/or via the spraying step of the process herein. A portion of the nonionic surfactant can also be incorporated after mixing and/or grinding the granules. Preferably, a portion of the nonionic surfactant is incorporated in at least each of these steps.
Generally, water-soluble nonionic surfactants are useful in the instant detergent compositions. Such nonionic materials include compounds produced by the condensation of alkylene oxide groups (hydrophilic in nature) with an organic hydrophobic compound, which may be aliphatic or alkyl aromatic in nature. The length of the polyoxyalkylene group which is condensed with any particular hydrophobic group can be readily adjusted to yield a water-soluble compound having the desired degree of balance between hydrophilic and hydrophobic elements.
Suitable nonionic surfactants include the polyethylene oxide condensates of alkyl phenols, e.g., the condensation products of alkyl phenols having an alkyl group containing from about 6 to 15 carbon atoms, in either a straight chain or branched chain configuration, with from about 3 to 80 moles of ethylene oxide per mole of alkyl phenol.
Included are the water-soluble and water-dispersible condensation products of aliphatic alcohols containing from 8 to 22 carbon atoms, in either straight chain or branched configuration, with from 3 to 12 moles of ethylene oxide per mole of alcohol.
Semi-polar nonionic surfactants include water-soluble amine oxides containing one alkyl moiety of from abut 10 to 18 carbon atoms and two moieties selected from the group of alkyl and hydroxyalkyl moieties of from about 1 to about 3 carbon atoms; water-soluble phosphine oxides containing one alkyl moiety of about 10 to 18 carbon atoms and two moieties selected from the group consisting of alkyl groups and hydroxyalkyl groups containing from about 1 to 3 carbon atoms; and water-soluble sulfoxides containing one alkyl moiety of from about 10 to 18 carbon atoms and a moiety selected from the group consisting of alkyl and hydroxyalkyl moieties of from about 1 to 3 carbon atoms.
Preferred nonionic surfactants are of the formula R 1 (OC 2 H 4 )OH, wherein R 1 is a C 10 -C 16 alkyl group or a C 8 -C 12 alkyl phenyl group, and n is from 3 to about 80.
Particularly preferred are condensation products of C 12 -C 15 alcohols with from about 5 to about 20 moles of ethylene oxide per mole of alcohol, e.g., C 12 -C 13 alcohol condensed with about 6.5 moles of ethylene oxide per mole of alcohol.
In a preferred embodiment, the nonionic surfactant is an ethoxylated surfactant derived from the reaction of a monohydroxy alcohol or alkylphenol containing from about 8 to about 20 carbon atoms, excluding cyclic carbon atoms, with from about 6 to about 15 moles of ethylene oxide per mole of alcohol or alkyl phenol on an average basis.
A particularly preferred ethoxylated nonionic surfactant is derived from a straight chain fatty alcohol containing from about 16 to about 20 carbon atoms (C 16-20 alcohol), preferably a C 18 alcohol, condensed with an average of from about 6 to about 15 moles, preferably from about 7 to about 12 moles, and most preferably from about 7 to about 9 moles of ethylene oxide per mole of alcohol. Preferably the ethoxylated nonionic surfactant so derived has a narrow ethoxylate distribution relative to the average.
The ethoxylated nonionic surfactant can optionally contain propylene oxide in an amount up to about 15% by weight of the surfactant and retain the advantages hereinafter described. Preferred surfactants of the invention can be prepared by the processes described in U.S. Pat. No. 4,223,163, issued Sep. 16, 1980, Builloty, incorporated herein by reference.
The most preferred composition contains the ethoxylated monohydroxyalcohol or alkyl phenol and additionally comprises a polyoxyethylene, polyoxypropylene block polymeric compound; the ethoxylated monohydroxy alcohol or alkyl phenol nonionic surfactant comprising from about 20% to about 80%, preferably from about 30% to about 70%, of the total surfactant composition by weight.
Suitable block polyoxyethylene-polyoxypropylene polymeric compounds that meet the requirements described hereinbefore include those based on ethylene glycol, propylene glycol, glycerol, trimethylolpropane and ethylenediamine as the initiator reactive hydrogen compound. Polymeric compounds made from a sequential ethoxylation and propoxylation of initiator compounds with a single reactive hydrogen atom, such as C 12-18 aliphatic alcohols, do not provide satisfactory suds control in the detergent compositions of the invention. Certain of the block polymer surfactant compounds designated PLURONIC and TETRONIC by the BASF-Wyandotte Corp., Wyandotte, Mich., are suitable in the surfactant compositions of the invention.
A particularly preferred embodiment contains from about 40% to about 70% of a polyoxypropylene, polyoxyethylene block polymer blend comprising about 75%, by weight of the blend, of a reverse block co-polymer of polyoxyethylene and polyoxypropylene containing 17 moles of ethylene oxide and 44 moles of propylene oxide; and about 25%, by weight of the blend, of a block co-polymer of polyoxyethylene and polyoxypropylene, initiated with tri-methylol propane, containing 99 moles of propylene oxide and 24 moles of ethylene oxide per mole of trimethylol propane.
Because of the relatively high polyoxypropylene content, e.g., up to about 90% of the block polyoxyethylene-polyoxypropylene polymeric compounds of the invention and particularly when the polyoxypropylene chains are in the terminal position, the compounds are suitable for use in the surfactant compositions of the invention and have relatively low cloud points. Cloud points of 1% solutions in water are typically below about 32° C. and preferably from about 15° C. to about 30° C. for optimum control of sudsing throughout a full range of water temperatures and water hardnesses.
In addition to the anionic and nonionic surfactants required in the detergent compositions of the invention herein, the detergent compositions may also contain surfactants selected from the group of ampholytic, zwitterinoic, cationic surfactants and mixtures thereof.
Ampholytic surfactants include derivatives of aliphatic or aliphatic derivatives of heterocyclic secondary and tertiary amines in which the aliphatic moiety can be straight chain or branched and wherein one of the aliphatic substituents contains from about 8 to 18 carbon atoms and at least one aliphatic substituent contains an anionic water-solubilizing group.
Zwitterionic surfactants include derivatives of aliphatic, quaternary, ammonium, phosphonium, and sulfonium compounds in which one of the aliphatic substituents contains from about 8 to 18 carbon atoms.
Cationic surfactants can also be included in the present detergent granules. Cationic surfactants comprise a wide variety of compounds characterized by one or more organic hydrophobic groups in the cation and generally by a quaternary nitrogen associated with an acid radical. Pentavalent nitrogen ring compounds are also considered quaternary nitrogen compounds. Halides, methyl sulfate and hydroxide are suitable. Tertiary amines can have characteristics similar to cationic surfactants at washing solution pH values less than about 8.5. A more complete disclosure of these and other cationic surfactants useful herein can be found in U.S. Pat. No. 4,228,044, Cambre, issued Oct. 14, 1980, incorporated herein by reference.
Cationic surfactants are often used in detergent compositions to provide fabric softening and/or antistatic benefits. Antistatic agents which provide some softening benefit and which are preferred herein are the quaternary ammonium salts described in U.S. Pat. No. 3,936,537, Baskerville, Jr. et al., issued Feb. 3, 1976, which is incorporated herein by reference.
Useful cationic surfactants also include those described in U.S. Pat. No. 4,222,905, Cockrell, issued Sep. 16, 1980, and in U.S. Pat. No. 4,239,659, Murphy, issued Dec. 16, 1980, both incorporated herein by reference.
Detergency Builders
Builders are typically employed to sequester hardness ions and to help adjust the pH of the laundering liquor. Such builders can be employed in concentrations up to about 85%, preferably from about 5% to about 50%, most preferably from about 10% to about 30%, by weight of the resultant compositions of the invention herein to provide their builder and pH-controlling functions. The builders herein include any of the conventional inorganic and organic water-soluble builder salts.
Such builders can be, for example, water-soluble salts of phosphates including tripolyphosphates, pyrophosphates, orthophosphates, higher polyphosphates, other carbonates, silicates, and organic polycarboxylates. Specific preferred examples of inorganic phosphate builders include sodium and potassium tripolyphosphates and pyrophosphates.
Nonphosphorus-containing materials can also be selected for use herein as builders. Specific examples of nonphosphorus, inorganic detergent builder ingredients include water-soluble bicarbonate, and silicate salts. The alkali metal, e.g., sodium and potassium, bicarbonates, and silicates are particularly useful herein.
Aluminosilicate ion exchange materials useful in the practice of this invention are commercially available. The aluminosilicates useful in this invention can be crystalline or amorphous in structure and can be naturally-occurring aluminosilicates or synthetically derived. A method for producing aluminosilicate ion exchange materials is discussed in U.S. Pat. No. 3,985,669, Krummel et al, issued Oct. 12, 1976, incorporated herein by reference. Preferred synthetic crystalline aluminosilicate ion exchange materials useful herein are available under the designations Zeolite A, Zeolite B, and Zeolite X. In an especially preferred embodiment, the crystalline aluminosilicate ion exchange material in Zeolite A and has the formula
Na.sub.12 [(AlO.sub.2).sub.12.(SiO.sub.2).sub.12 ].xH.sub.2 O
wherein x is from about 20 to about 30, especially about 27.
Water-soluble, organic builders are also useful herein. For example, the alkali metal, polycarboxylates are useful in the present compositions. Specific examples of the polycarboxylate builder salts include sodium and potassium, salts of ethylenediaminetetraacetic acid, nitrilotriacetic acid, oxydisuccinic acid, mellitic acid, benzene polycarboxylic acid, polyacrylic acid, and polymaleic acid.
Other desirable polycarboxylate builders are the builders set forth in U.S. Pat. No. 3,308,067, Diehl, incorporated herein by reference. Examples of such materials include the water-soluble salts of homo- and co-polymers of aliphatic carboxylic acids such as maleic acid, itaconic acid, mesaconic acid, fumaric acid, aconitic acid, citraconic acid, and methylenemalonic acid.
Other suitable polymeric polycarboxylates are the polyacetal carboxylates described in U.S. Pat. No. 4,144,226, issued Mar. 13, 1979 to Crutchfield et al, and U.S. Pat. No. 4,246,495, issued Mar. 27, 1979 to Crutchfield et al, both incorporated herein by reference. These polyacetal carboxylates can be prepared by bringing together under polymerization conditions an ester of glyoxylic acid and a polymerization initiator. The resulting polyacetal carboxylate ester is then attached to chemically stable end groups to stabilize the polyacetal carboxylate against rapid depolymerization in alkaline solution, converted to the corresponding salt, and added to a surfactant.
The compositions herein preferably contain little (e.g., less than 10%, preferably less than 5%, by weight) or no phosphate builder materials. The presence of higher levels of tripolyphosphate improves solubility of the compositions to the point where hydrophobic amorphous silicate provides little or no additional improvements. However, sodium pyrophosphate reduces solubility so that the benefit provided by the hydrophobic amorphous silicate is greater in granular compositions containing pyrophosphate.
Other Ingredients
Bleaching agents and activators useful herein are also described in U.S. Pat. No. 4,412,934, Chung et al., issued Nov. 1, 1983, U.S. Pat. No. 4,483,781, Hartman, issued Nov. 20, 1984, U.S. Pat. No. 4,634,551, Burns et al, issued Jan. 6, 1987, and U.S. Pat. No. 4,909,953, Sadlowski et al, issued Mar. 20, 1990, all of which are incorporated herein by reference. Chelating agents are also described in U.S. Pat. No. 4,663,071, Bush et al., from Column 17, line 54 through Column 18, line 68, incorporated herein by reference. Suds modifiers are also optional ingredients and are described in U.S. Pat. No. 3,933,672, issued Jan. 20, 1976 to Bartoletta et al., and U.S. Pat. No. 4,136,045, issued Jan. 23, 1979 to Gault et al., both incorporated herein by reference.
Suitable smectite clays for use herein are described in U.S. Pat. No. 4,762,645, Tucker et al, issued Aug. 9, 1988, Column 6, line 3 through Column 7, line 24, incorporated herein by reference. Suitable additional detergency builders for use herein are enumerated in the Baskerville patent, Column 13, line 54 through Column 16, line 16, and in U.S. Pat. No. 4,663,071, Bush et al, issued May 5, 1987, both incorporated herein by reference.
Other ingredients suitable for inclusion in a granular laundry detergent composition can be added to the present compositions. These include bleaches, bleach activators, suds boosters or suds suppressors, anti-tarnish and anticorrosion agents, soil suspending agents, soil release agents, germicides, pH adjusting agents, non-builder alkalinity sources, chelating agents, smectite clays, enzymes, enzyme-stabilizing agents and perfumes. Such ingredients are described in U.S. Pat. No. 3,936,537, issued Feb. 3, 1976 to Baskerville, Jr. et al., incorporated herein by reference.
The following non-limiting Examples illustrate the process of the invention and facilitates its understanding. As used in the following Examples, "LAS" is C 14-15 alkylbenzene sulfonate surfactant, "AE(0.35)S" is C 14-15 alkyl ethoxylated sulfate (EO=0.35) surfactant, "PEG" is polyethylene glycol, and "Nonionic" is C 12-13 alkyl ethoxylate (EO=6.5).
EXAMPLE I
The following example illustrates the process of the invention and the detergent composition produced by it.
______________________________________ % Weight______________________________________Base Granule Composition65%/35% LAS/AE(0.35)S 16.55Aluminosilicate 26.30Sodium Carbonate 11.27Sodium Silicate (1.6r) 0.60Polyacrylate 3.24Brightener 0.20PEG (MW = 4000) 1.74Sulfate 8.85Moisture 9.26Misc 0.33 78.34Nonionic Spray-On after Tower 2.00Finished ProductSodium Carbonate 16.16Sodium Perborate 1.00Perfume 0.40Nonionic Spray-On after mixer 1.00Enzymes 1.10 100.00______________________________________
The above base granule is prepared into an aqueous slurry mix in any commercially available heated detergent crutcher and spray dried in a counter-current spray drying tower. The drying air has an inlet temperature of about 310° C., and an outlet temperature of about 90°-105° C. The spray dried granular product exits the spray drying tower at a temperature of about 100° C. and falls via a chute onto a moving cross conveyor belt. The product stream on the belt is about 15-25 cm wide and 3-6 cm deep. As the base spray dried granules pass on the belt, 2.00% by weight of C 12-13 alkyl ethoxylate (EO=6.5) nonionic surfactant in a liquid state at a temperature of about 140° C. is sprayed on the granules using four nozzles spread along the distance of the belt, and spaced at even intervals in the first 50% of the belts distance from the tower end. This positioning takes advantage of the higher temperature of the product at the tower end of the belt. The nozzles are two-fluid, that is using a parallel air stream to assist in evenly dispersing the liquid nonionic onto the product on the belt. Nozzles are positioned 20-30 cm above the product, and the nozzle delivers a square footprint which minimizes spray onto the edge of the belt or into the belt housing, thereby minimizing maintenance, maximizing reliability of the process, and maximizing metering accuracy of the liquid nonionic to the base granule.
To enhance the mixing of the liquid into the product stream, two chains are positioned in the last 50% of the belt length. These link chains lay directly on the belt and serve to roll-over and tumble the product, thereby mixing the top liquid-loaded layer into the un-coated lower layer. The nonionic at this time permeates the base granule, allowing the nonionic surfactant to mix with the anionic surfactant of the base granule. Because the anionic surfactant is still in a liquid phase at this time, and has yet to cool and crystallize, the nonionic is able to actually intersperse with the anionic. This mixing of surfactants is a factor in the improved solubility of the product.
From the exit end of the belt, the product is exposed to an airlift, where-by the total mass of the product stream is picked-up by a stream of air and conveyed vertically to the top of the airlift. The base granule stream exits the particle size classifier at the top of the airlift at a temperature of about 50° C. The total residence time from the point of nonionic application at the base of the spray tower to the exit chute at the top of the airlift is between 20 and 60 seconds.
Thereafter, the base granules are fed directly into a Lodige CB-100 mixer which is operated at a speed of about 300 rpms. The flowrate is dependent on the rate of the spray-tower. The CB-100 breaks apart large base granules, thereby exposing the inside surface area and increasing the overall surface area of the product, while also allowing any liquid nonionic which did not permeate the base granules to be mixed from the surface of one base granule into the newly exposed inside surface of another base granule. This mixing step increases the permeation of the liquid nonionic surfactant into the anionic surfactant, improving even further the solubility of the product as well as the flow properties of the detergent composition. The CB-100 mixer also decreases the average particle size of the product by about 100 microns and therefore also serves as a grinder. The decreased particle size, or increased surface area, also improves the solubility and flow properties of the detergent composition. After exiting the Lodige CB-100, the base granules are mixed with other detergent ingredients per the above formulation.
When tested for solubility, the product is found to be unexpectedly substantially better than the same product that did not undergo the described process. When tested for physical flow properties, the detergent composition has unexpectedly substantially improved cake grade and stability. The detergent composition produced by the process described herein has significantly less sticky, mealy, or cakey properties. Similarly, in a standard stability test which exposes the detergent composition to high humidity and temperature for an extended period of time (e.g. 4 weeks), the detergent composition produced according to the instant process unexpectedly demonstrated a substantially improved stability profile, improved resistance to moisture gain, improved cake grades, and improved scoopability. Scoopability is a key consumer attribute as it measures the resistance of the product to scooping using the standard laundry scoop.
EXAMPLE II
This Example illustrates another process and composition produced thereby in accordance with the invention.
______________________________________ % Weight______________________________________Base Granule Composition55%/45% LAS/AE(O.35)S 16.42Aluminosilicate 26.50Sodium Carbonate 1.43Sodium Silicate (1.6r) 0.60Polyacrylate 2.57Brightener 0.20PEG (MW = 4000) 1.76Sulfate 37.56Moisture 8.10Misc 0.48 95.42Nonionic Spray-On after Tower 1.25Finished ProductSodium Perborate 2.18Perfume 0.17Nonionic Spray-On after mixer 0.25Suds Suppresser 0.10Enzymes 0.63 100.00______________________________________
The detergent composition presented above was made as described in Example I above. The detergent composition demonstrates the same unexpected substantially improved flow properties and solubility as recited in Example I. In this example >80% by weight of the total nonionic surfactant in the composition is applied prior to the airlift or the Lodige CB-100 mixer. Additionally, this product has significantly fewer admixes and yet, exhibits improved flow properties. Admixes, especially the inorganic salts like sodium carbonate, sodium sulfate, and sodium chloride, are known to improve the physical properties of a detergent product. The process described in this Example allows for a detergent composition that is comprised of greater than 95% by weight of the base granule to have similarly good physical property characteristics. The detergent composition also demonstrates excellent flowability which is a key consumer attribute as it measures how well a detergent pours from a carton or out of a scoop. This attribute is particularly important for those detergent products which are low in admixed ingredients and high in spray-dried base granule composition (e.g. those compositions comprising greater than 90% of the base granule).
Having thus described the invention in detail, it will be obvious to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is described in the specification. | A process which produces a detergent composition that exhibits improved solubility as well as improved flow properties is provided. The improved solubility can be detected by evidence of increased solubility of the surfactants in the washing solution and/or by the decreased amount of detergent residue left on laundered clothes. It has now been discovered that incorporating nonionic surfactant on and/or in spray-dried detergent granules before cooling the granules and while they are relatively hot, and thereafter cooling and mixing the granules improves the solubility and flow properties of the granules. | 2 |
FIELD OF THE INVENTION
The present invention relates to controlling silica deposits in aqueous systems. More particularly, the present invention relates to inhibiting silica/silicate deposition in cooling and boiler water systems using synergistic combinations which include a phosphonic acid.
BACKGROUND OF THE INVENTION
The problem of scale formation and its attendant affects have troubled water systems for many years. For instance, scale tends to accumulate on the internal walls of various water systems, such as boiler and cooling water systems, thereby reducing heat transfer properties and fluid flow through heat exchanger tubes.
One particular type of deposit, silica, is especially troublesome in some systems. Where the water used in cooling the systems and water cooled industrial heat exchangers is taken directly from lakes, rivers, ponds, or municipal water sources, various amounts of dissolved and suspended solids, including silica, are present. Problems are compounded in operations where water is concentrated, or cycled up, during the process, e.g., cooling systems. As the water evaporates, the silica concentrations increase increasing both the occurrence and the degree of deposition. Increasing silica concentrations can also result in monomeric silica undergoing polymerization to form gelular and/or colloidal silica which can form tenacious deposits.
In cooling water systems, silica and silicate compounds form deposits on the internal metal surfaces in contact with the water flowing through the system. In this manner, heat transfer efficiency becomes severely impeded, which in turn has a deleterious effect on the overall operating efficiency of the cooling water system. Silica and silicate deposition also causes problems on other conduit and piping surfaces, as well as on equipment such as valves, nozzles and pumps.
Although current industrial cooling systems make use of sophisticated external treatments of the feed water, e.g., coagulation, filtration, softening of water prior to it being fed into the water system, these operations are only moderately effective. In all cases, external treatment does not in itself provide adequate treatment since muds, sludge, silts, and dissolved solids such as silicate can escape the treatment and eventually are introduced into the system.
Silica (silicon dioxide) appears naturally in a number of crystalline and amorphous forms, all of which are sparingly soluble in water; thus leading to the formation of undesirable deposits. Silicates are salts derived from silica or the silicic acids, especially orthosilicates and metosilicates, which may combine to form polysilicates. All of these, except the alkali silicates are sparingly soluble in water. A number of different forms of silica and silicate salt deposits are possible, and formation depends, among other factors, on the temperature and pH of the water.
Various methods have been utilized for resolving the problem of sludge and silt, including silica, deposition. U.S. Pat. No. 5,378,368 discloses the use of polyether polyamino methylene phosphonates to control silica/silicate deposition in industrial water systems. The polyether polyamino methylene phosphonates may be used alone or in combination with a polymer additive.
U.S. Pat. No. 5,078,879 discloses the use of 2 phosphonobutane tricarboxylicate acid-1,2,4 alone or preferably in combination with an anionic polymer such as a carboxylic/sulfonic polymer, to control the formation of silica/silicate deposits in aqueous systems.
U.S. Pat. No. 4,933,090 discloses the use of a select phosphonate and optionally a carboxylic/sulphonic/polyalkylene oxide polymer to control silica/silicate deposition.
U.S. Pat. No. 4,874,527 discloses the use of an imine polymer, a phosphanate and optionally a source of molybdate or borate ions to control the formation of silica/silicate deposits in aqueous systems.
U.S. Pat. No. 5,158,685 discloses the use of a combination of a hydroxyphosphonoacetic acid and an acrylic acid/alyl hydroxy propyl sulphonate ether polymer to control silica/silicate deposition in cooling water systems.
U.S. Pat. No. 5,300,231 discloses the use of polyether polyamino methylene phosphonates in combination with hydroxyphosphono acetic acid or amino tris methylene phosphonate to control silica/silicate deposition in various industrial water systems.
U.S. Pat. No. 4,405,461 discloses the use of a treatment comprising an amine to which is attached at least a pair of terminal groups selected from furfuryl and saturated or unsaturated hydrocarbon radicals substituted with one or more hydroxy and carboxy, or a hydrohalide thereof to control the deposition of silica-containing scales.
DETAILED DESCRIPTION OF THE INVENTION
In accordance with the present invention, it has been discovered that synergistic combinations which include a phosphonic acid are effective treatment agents for reducing the deposition of silica/silicate in aqueous systems. The method of the present invention comprises adding an effective amount of a synergistic combination which includes a phosphonic acid to an aqueous system being treated.
The treatment for aqueous systems of the present invention is a synergistic combination of the phosphonic acid (a) diethylenetriamine penta (methylene phosphonic acid) with (b) 2 phosphonobutane-1,2,4-tricarboxylic acid; high molecular weight, 3:1, copolymer of acrylic acid/allyhydroxypropylsulfonate ether; ethylene oxide-propylene oxide block copolymers; and polyepoxysuccinic acids and salts thereof.
A diethylenetriamine penta (methylene phosphonic acid) is available commercially from Solutia under the tradename Dequest 2060. A 2-phosphonobutone-1,2,4-tricarboxylic acid is available commercially from Bayer under the tradename Bayhibit AM. Ethylene oxide-propylene oxide block copolymers are available commercially from BASF under the tradename Pluronic L63 and Pluronic L44. A polyepoxy-succinic acid is available commercially from BetzDearborn under the tradename Coag 129.
An effective amount of a synergistic combination can be added to an aqueous system being treated. As used herein, the term effective amount is that amount necessary to control silica/silicate deposition in the system being treated. Generally, the effective amount will range from about 1 to 100 ppm, on an active basis based upon the total weight of the aqueous system being treated.
As used herein, the term controlling the silica/silicate deposition is to include inhibition of silica polymerization, threshold precipitation inhibition, stabilization, dispersion, solubilization, and/or particle size reduction of silica, silicates, calcium and magnesium silicates, and silicon ions. The treatments of the present invention are threshold silicate precipitation inhibitors which also stabilize, disperse and solubilize silica and silicates, and generally reduce the particle size of any precipitated material.
Aqueous system as used herein, is meant to include any type of system containing water, including, but not limited to, cooling water systems, boiler water systems, desalination system, gas scrubber water systems, evaporator systems, paper manufacturing systems, mining systems, and the like.
The components of the synergistic combination of the present invention are well known to those skilled in water treatment art, and are commercially available. The treatment materials of the present invention may be added to the aqueous system being treated by any convenient means. The treatment materials of the present invention may be added to the aqueous system concurrently, as a one drum or two drum treatment or consecutively so as to form the synergistic combination in situ. A preferred method of addition is to the makeup water streams. Additionally, other conventional water treatment agents such as corrosion inhibitors can be used in combination with treatments of the present invention.
The present invention will now be further described with reference to a number of specific examples which are to be regarded as illustrative, and not as restricting the scope of the present invention.
EXAMPLES
The efficiency of the synergistic combinations of the present invention to inhibit silica/silicate deposition in an aqueous system was evaluated in a stirred batch reverse osmosis apparatus. The apparatus was a pressurized water filter where the filter media was a reverse osmosis membrane and the pressure was provided by compressed nitrogen. An overhead stirrer paddle was positioned near the surface of the membrane filter to provide turbulence to minimize concentration effects.
A synthetic feed water containing 100 ppm silica as SiO 2 was added to the apparatus with and without treatment. The feed water was concentrated approximately ten times over a 30-40 minute period, such that the water at the end of the experiment contained about 1000 ppm SiO 2 . At the conclusion of a run, the reverse osmosis membrane was removed and analyzed for silica to quantify the amount of silica deposited on the membrane. Tests with a chemical treatment were compared to control tests (no chemical treatment) to calculate a percent silica inhibition. The results are summarized in Table I. The following legend identifies the treatment materials.
______________________________________LegendSymbol Material______________________________________A Diethylenetriamine penta(methylene phosphoric acid)B 2-phosphonobutane-1,2,4-tricarboxylic acidC High molecular weight, 3:1, acrylic acid/allylhydroxy- propylsulfonate etherD Ethylene oxide-propylene oxide block copolymer HLB = 8-12E Ethylene oxide-propylene oxide block copolymer HLB = 1-7F Polyepoxysuccinic acid______________________________________
TABLE 1______________________________________Treatment Feed Rate (ppm Active) % Silica Inhibition______________________________________A 10.0 53A/F 7.5/2.5 57A/F 5.0/5.0 46A/F 2.5/7.5 47F 10 49A/D 7.5/2.5 56A/D 5.0/5.0 50A/D 2.5/7.5 59D 10 45A/E 7.5/2.5 58A/E 5.0/5.0 40A/E 2.5/7.5 59E 10 37A/C 7.5/2.5 57A/C 5.0/5.0 54A/C 2.5/7.5 23C 10 23A/B 7.5/2.5 64A/B 5.0/5.0 62A/B 2.5/7.5 56B 10 27______________________________________
The data in Table 1 shows that synergistic combinations exist which provide silica control significantly higher than would be expected from the effect of the individual components.
While this invention has been described with respect to particular embodiments thereof, it is apparent that numerous other forms and modifications of this invention will be obvious to those skilled in the art. The appended claims and this invention generally should be construed to cover all such obvious forms and modifications which are within the true spirit and scope of the present invention. | A method of controlling the deposition of silica-containing scales and their adhesion to surfaces in contact with an aqueous system is disclosed which comprises adding to the aqueous system a synergistic combination of:
(a) diethylenetriamine penta methylene phosphonic acid; and
(b) a material selected from the group consisting of 2 phosphonobutane-1,2,4-tricarboxylic acid; high molecular weight, 3:1, acrylic acid/allylhydroxypropylsulfonate ether copolymer; ethylene oxide-propylene oxide block copolymers; and polyepoxysuccinic acid and salts thereof. | 2 |
RELATED APPLICATION INFORMATION
This application is a continuation of application Ser. No. 08/897,944, filed Jul. 21, 1997 now U.S. Pat. No. 5,824,058, which is a continuation of application Ser. No. 08/550,511, filed Oct. 30, 1995, now abandoned, which is a continuation of application Ser. No. 08/065,238, filed May 20, 1993 now U.S. Pat. No. 5,480,423.
FIELD OF THE INVENTION
This invention relates to delivering prostheses into the body.
BACKGROUND OF THE INVENTION
Prostheses, such as stents, grafts and the like, are placed within the body to improve the function of a body lumen. For example, stents with substantial elasticity can be used to exert a radial force on a constricted portion of a lumen wall to open a lumen to near normal size.
These stents can be delivered into the lumen using a system which includes a catheter, with the stent supported near its distal end, and a sheath, positioned coaxially about the catheter and over the stent.
Once the stent is located at the constricted portion of the lumen, the sheath is removed to expose the stent, which is expanded so it contacts the lumen wall. The catheter is subsequently removed from the body by pulling it in the proximal direction, through the larger lumen diameter created by the expanded prosthesis, which is left in the body.
SUMMARY OF THE INVENTION
This invention provides smooth delivery and accurate positioning of prostheses in the body. In embodiments, systems are provided that include elongate members extending generally along the axis of a supporting catheter to a free ends. The elongate members extend through openings in the prosthesis to maintain the position of the prosthesis on the catheter. The prosthesis can be released from the catheter by relative axial motion of the catheter and the elongate members such that the free ends are removed from the openings in the prosthesis. In embodiments, the elongate members hold the distal end of a self-expanding stent at a desired axial location and in radial compaction as a restraining sheath is withdrawn. The friction between the sheath and stent puts the stent under tension, which reduces the radial force on the sheath wall, allowing smoother retraction. Proximal portions of the stent radially expand and axially shorten. The distal end, however, is maintained at the desired axial location and released from the catheter to contact the body lumen wall without substantial axial shortening.
In an aspect, the invention features a system for positioning a prosthesis in contact with tissue within a patient. The system includes a prosthesis having proximal and distal ends and a tissue-engaging body therebetween. The prosthesis has a radially compact form for delivery into the patient and is radially expandable along its body for engaging tissue. The length of the prosthesis varies in dependence on the expansion of the body. The system further includes a catheter having a portion for supporting the prosthesis in the compact form during delivery into the patient and constructed for expanding the prosthesis in contact with tissue. The portion includes a member positioned to engage the prosthesis near the distal end to maintain a corresponding portion of the prosthesis radially compact at a predetermined axial location, while proximal portions of the prosthesis are radially expanded to engage tissue. The portion of the prosthesis engaged by the member is releasable from the catheter at an axial location substantially corresponding to the predetermined location by relative axial motion between the member and the prosthesis, so the free end of the member disengages the prosthesis.
Embodiments may include one or more of the following features. The prosthesis has, near its distal end, an opening through the tissue-engaging body and the member extends generally along the axis of the catheter to a free end that engages the prostheses by extending through the opening and the portion of the prosthesis corresponding to the opening is released by axial motion so the free end of the member is removed from the opening. The opening may include a series of openings positioned around the circumference of the prosthesis and the member is a corresponding series of elongated members, which pass through the series of openings. The member extends distally to the free end so release of the prosthesis from the catheter is by moving the members proximally relative to the prosthesis. The member is fixed on the catheter so release of the prosthesis from the catheter is by moving the catheter relative to the prosthesis. The elongate member extends at an angle with respect to the axis of the catheter to form a predefined wedge space between the member and the catheter for engaging the prosthesis. The angle is about 3-8 degrees. The member is formed of a flexible material that deflects outwardly in response to a radial force, to release the free end of the member from the opening. The member is a superelastic wire. The length of the portion of the member passing through the opening is smaller than the expanded diameter of the prosthesis. The prosthesis is a tubular-form prosthesis positioned coaxially about the supporting portion of the catheter in the radially compact form. The prosthesis is formed of a patterned filament and the opening is formed by the pattern. The prosthesis is knitted and the opening is formed by knit-loops in the knit pattern. The opening is the end loop of the knit pattern. The prosthesis is self-expanding. Portions of the self-expanding prosthesis corresponding to the member are maintained in compact form by the member and portions remote from the member are maintained in compact form by a restraint. The restraint is an axially retractable sheath and the self-expanding prosthesis engages the sheath with substantial friction to place the prosthesis under tension as the sheath is retracted.
In another aspect, the invention features a system for positioning a prosthesis in contact with tissue on the wall of a lumen of a patient. The system includes a tubular prosthesis having a proximal and distal end and a tissue-engaging body therebetween. The prosthesis has a radially compact form for delivery into the patient and is radially expandable along its body for engaging tissue. The length of the prosthesis varies in dependence on expansion of the body. The prosthesis is formed of a patterned filament and includes a series of openings through the tissue-engaging body of the prosthesis about the circumference of the prosthesis, near the distal end. The system further includes a catheter having a portion for supporting the prosthesis coaxially about the portion in the compact form for delivery into the patient and constructed for expanding the prosthesis into contact with tissue. The portion includes a series of elongate members arranged about the circumference of the catheter, fixed to the catheter, and extending generally along the axis of the catheter to free ends positioned to pass through corresponding openings about the circumference of the tissue-engaging body of the prosthesis. The members maintain corresponding portions of the prosthesis radially compact at a predetermined axial location, while proximal portions of the prosthesis are radially expanded to engage tissue. The portion of the prosthesis corresponding to the openings is releasable from the catheter at an axial location substantially corresponding to the predetermined location by moving the catheter proximally so the free ends of the members are removed from the openings.
Embodiments may include one or more of the following features. The prosthesis is self-expanding and the elongate members in the openings maintain the distal end of the prosthesis compact after other portions of the prosthesis are radially expanded. The portions of the prosthesis proximal of the members are maintained compact by a retractable sheath. The prosthesis engages the sheath with substantial friction to place the prosthesis under tension as the sheath is retracted. The elongate members are formed of superelastic metal wires. The elongate members are formed of a flexible material that deflects outwardly in response to a radial force of expansion of the prosthesis to release the free ends of the members from the openings. The length of the portions of the elongated strands passing through the loops is smaller than the expanded diameter of the prosthesis. The elongated strands extend at an angle with respect to the axis of the catheter. The angle is about 3-8 degrees.
In another aspect, the invention features a system for positioning a self-expanding prosthesis in the body. The system includes a self-expanding prosthesis having a proximal end and a distal end and a tissue-engaging body therebetween. A catheter is provided having a portion supporting a prosthesis in a radially compact form. The portion of the catheter supporting the prosthesis includes a member positioned to engage the distal end of the prosthesis to maintain corresponding portions of the prosthesis compact at a predetermined axial location with respect to the catheter while other portions of the prosthesis are radially expanded to engage tissue. The system includes a retractable sheath positioned over and in contact with the prosthesis when the prosthesis is in the compact form. A tensioning element applies an axial force to the prosthesis to reduce frictional force between the sheath and the prosthesis while retracting the sheath to expose the prosthesis.
The sheath may be a restraining sheath that maintains portions of the prosthesis compact against the radial expansion force of the prosthesis and the tensioning element is formed by the sheath, engaged by the prosthesis with substantial frictional force to place the prosthesis under tension as the sheath is retracted.
In another aspect, the invention features methods of positioning a prosthesis in the body. For example, the method may include providing a system as described above, positioning the system in a body lumen with the distal end of the prosthesis in the compact form located substantially adjacent the axial location of the lumen wall corresponding to the desired distal extension of the prosthesis, expanding portions of the prosthesis proximal of the distal end to engage the wall of the lumen, and withdrawing the catheter proximally so the distal end is disengaged from the catheter and expanded against the lumen wall. The prosthesis may be positioned at a location adjacent a side duct branching from the lumen. The body lumen may be the bile duct. Many methods are evident from the description herein.
The advantages of the invention are numerous. For example, systems of the invention can provide accurate positioning of a prosthesis, even a self-expanding stent which changes its axial length upon expansion. Accurate positioning of the prosthesis is particularly important in cases where the portion of the body lumen to be treated is adjacent a tissue feature, such as another body lumen, that should not be occluded by the prosthesis. A tumor in the bile duct that is located adjacent the duodenum is one example. It is desirable to center the prosthesis about the tumor, but care must be taken so that the end of the prosthesis does not extend beyond the duodenum. Otherwise the motion of the body and the flow of food particles may drag the stent from the bile duct.
Further features and advantages follow.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a side view, with a sheath in cross section, of a delivery system according to the invention;
FIG. 1 a is an enlarged perspective view, with the prosthesis partially cut-away, of the distal end of the system in FIG. 1 with the sheath partially retracted;
FIGS. 2-2 f illustrate the operation and use of the system in FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Structure
Referring to FIGS. 1-1 a, a system 2 according to the invention for delivering a prosthesis to the bile duct includes a catheter body 4 carrying a prosthesis 6 , which is held in a compact state for most of its length by a retractable restraining sheath 8 . The prosthesis 6 is a self-expanding knit-form stent having a series of end loops 10 . The distal end 14 of the catheter includes a series of flexible elongate members 16 running generally parallel to the axis of the catheter. One end of the members 16 is attached to the catheter body 4 . The other, free end 17 , of the members 16 extends through the end loops 10 , holding the end loops at a predetermined axial position and in compact form, even when proximal portions 18 of the stent 6 expand outwardly after retraction (arrow 20 ) of the sheath 8 . As will be discussed in further detail below, end loops 10 of the prosthesis 6 can be released from the catheter, and expanded against the lumen wall at a predetermined location, after most of the length of the stent has expanded to engage the lumen, by axially withdrawing the catheter body 4 so the free ends 17 of the members 16 slip back through the end loops 10 . In this manner, the end loops 10 are positioned at a defined location along the lumen wall, even though the self-expanding stent reduces its axial length upon radial expansion due to elastic rebounding effects and the loose knit nature of the structure. Moreover, sheath retraction is smoother since the stent is placed in tension by retraction of the sheath, which simultaneously reduces the axial force on the sheath wall.
The device 2 has an overall length L 1 , about 80 cm. The catheter body 4 (nylon) has a proximal portion 22 of constant diameter, about 0.11 inch, over a length, L 2 , of about 69 cm, and a distal portion 24 , which includes a taper 26 to a smaller diameter, about 0.053 inch, over a length, L 3 , about 1.0 cm. Following the taper 26 , a constant diameter portion 27 extends for a length, L 4 , about 10 cm, along which the stent 6 is positioned. The catheter body 4 further includes enlarged tip 30 (nylon with radiopaque filler) of length, L 5 , about 22 mm, maximum outer diameter 0.031 inch, with distal taper 32 (8-9 mm in length) for atraumatic advance, a step portion 33 (4 mm in length), which engages the sheath when the sheath is fully distally extended during entry into the body, and a proximal taper 34 (8-9 mm in length). A guidewire lumen 37 (phantom, FIG. 1 ), about 0.039 inch, for delivering the device over a guidewire, extends the length of the catheter body 4 , terminating distally at an end opening 39 in the enlarged tip 30 (FIG. 1 a ). The most proximal end of the body includes a luer lock device 7 . The catheter includes three radiopaque markers (tantalum bands). A proximal marker 9 indicates the proximal end of the stent in the compacted state. A central marker 11 indicates the proximal end of the stent in the expanded state. A distal marker 11 indicates the distal end of the stent. As will be discussed below, the distal marker 13 also deflects wires that form members 16 off the catheter body axis.
The stent is a self-expanding knitted stent, knitted of an elastic wire material (0.005 inch diameter), such as a superelastic nitinol-type material (e.g. Strecker stent®, Boston Scientific, Watertown, Mass.). The stent includes 40 rows along its length, with 8 knit loops in each row around the circumference. In the compact condition (FIG. 1 ), the outer diameter of the stent is about 2.8 mm, and the length, L 6 , about 10 cm. At full expansion, the stent has an outer diameter of 10 mm and shortens axially, to a length of about 6 cm. A feature of this invention is that the stent can be accurately positioned in spite of the axial length reduction on expansion, by maintaining the axial position of the distal end of the stent in the compact state, with members 16 , while allowing the proximal portions to radially expand and axially relax. After the variations at the proximal portions, the distal end is released from the members so it expands without substantial axial variation, and contacts the lumen wall at a predetermined location determined by axially aligning the radiopaque marker 13 .
The restraining sheath 8 (teflon), has a length, L 7 , about 60 cm and a wall thickness of about 0.006 inch. A handle 28 , located on portions of the sheath outside the body, is slid axially proximally to retract the sheath and expose the stent. As illustrated particularly in FIG. 1 a, the stent 6 engages the inner wall of the sheath 8 , owing to the elastic nature of the stent which causes it to push radially outward when in the compact state. A feature of the invention is that the sheath retraction is made easier and smoother. With only the distal end of the stent held axially in place by the members 16 , the friction between the inner wall of the sheath and the stent places the stent under tension during sheath retraction, which causes the stent to elastically elongate slightly. This tension reduces the radial force of the stent on the inner wall and also prevents the loops in adjacent knit rows from intertangling and bulging radially outwardly.
The members 16 are positioned equidistantly radially about the catheter 4 , with one member for each of the eight end loops of the stent. (Only five members are visible in FIG. 1 a, the other three members being positioned on the opposite side of the catheter.) The members 16 are formed of straight wires (0.006 inch diameter) with an overall length of 13 mm. A proximal portion 15 , length, L 8 , about 4 mm, is attached to the catheter by a layer 19 of UV epoxy. (Another radiopaque band may cover the wires in the region between the epoxy and marker 13 and heat shrink tube may be used to cover the whole attachment assembly from epoxy 19 to marker 13 .) The portion of the catheter body distal of the epoxy includes radiopaque marker 13 , a tantalum band (about 0.060 inch wide) (Nobel Met, Inc., Roanoke, Va.), that creates a slight (0.003 inch) radial step from the catheter body, causing the normally straight wires to be deflected at an angle of about 3-8 degrees when the sheath is retracted. (With the sheath positioned over the wires, the free ends of the wires engage the inner wall of the sheath and the wires are bent inward slightly and partially supported against the proximal taper 34 of the enlarged end 30 .) The deflected portion of the wires extend beyond the marker 13 for a distance along the catheter axis, L 9 , about 6 mm to the free ends 17 . The deflection of the wires and the taper 34 of enlarged end 30 , create a predetermined space just distal of the marker 13 , slightly smaller in width than the diameter of the stent wire, where the end loops are positioned. As illustrated particularly in FIG. 1 a, the end loops are wedged in this space between the members 16 and taper 34 . In this position the end loops are maintained axially and radially stable when the sheath is retracted, but are also easily dislodgeable from the wedged position when the catheter body is moved proximally, after proximal portions of the stent have been expanded to engage the lumen wall. The angle of the members is about equal to the angle of the taper 34 (e.g. about 8°). (The angle of the members may be made larger than the angle of the back taper 34 so friction between the end loops and back taper is reduced as the catheter is withdrawn proximally.) In this embodiment, the end loops are wedged at a location toward the proximal end of the members 16 , about 1 mm from the radiopaque marker 13 . In this position, the radial expansion force of the stent does not overcome the stiffness of the wires and cause them to deflect outward and prematurely release the stent. When the catheter is slid proximally, the end loops are easily dislodged from the wedged location and slide along the members until the radial force overcomes the stiffness of the members, causing them to deflect outward, and the end loops are released. The length of the members is kept smaller than the expanded radius of the stent, yet long enough to hold the end loops compact. Further, the members are formed of an elastic material, such as a superelastic nitinol-type material, that does not plastically deform when the members deflect as the prosthesis is released or as the device is being delivered along a torturous path into a duct. Other embodiments can use filaments formed of other materials, for example, stiff polymers. Embodiments may also use filaments that have high stiffness and do not deflect under the radial expansion of the stent at any positioning of the end loops along their length, but rather, the end loops are removed only by the axial motion of the filaments. Systems such as described above can position the distal end of a stent within ±5 mm of a desired axial location, according to use in an operation such as described in the following.
Use and Operation
Referring now to FIGS. 2-2 f, use of the delivery system for positioning a stent in the bile duct is illustrated. Referring to FIG. 2, the system may be used to treat an obstruction 40 , such as a tumor, in the bile duct 42 . The bile duct extends from the liver 44 to the duodenum 48 . The system 2 is particularly useful for positioning a prosthesis in cases where the obstruction 40 is located near the duodenum 48 . In such cases, it is particularly important to position the distal end of the prosthesis so that the overlap with the duodenum is minimized. Otherwise the action of the duodenum may draw the prosthesis axially out of the bile duct into the intestine.
Typically, the occlusion substantially closes off the bile duct which has a healthy lumen diameter of about 8-10 mm. The obstruction is typically around 4 cm in length. To prepare the duct for the prosthesis, the physician accesses the liver with an access sheath 46 . A collangeogram is taken to locate the occlusion. Using ultrasound or fluoroscopy, a guidewire 49 (0.038 inch) is positioned through the access sheath, liver 44 and into the bile duct 42 , such that it crosses the lesion 40 and extends into the duodenum 48 . A series of dilators (not shown), for example, hard teflon, are tracked over the guidewire to widen the bile duct, tissue of a shoe leather-like texture, in preparation for the stent. The largest dilator approximates the full healthy lumen diameter. Alternatively, the largest dilator approximates the maximum outer diameter of the system with the prosthesis in the compact state. Balloon expansion devices can be used to the same effect before the system is positioned in the duct (or sometimes after the stent has been placed in the lumen). After preparing the lumen, the system 2 is tracked over the guidewire, through the sheath 46 , liver 44 , and into the bile duct 42 .
Referring to FIG. 2 a, the system is slid axially distally until distal radiopaque marker 13 is positioned axially at a location at least about 1 cm distal of the occlusion 40 . This location substantially corresponds to the position the distal end of the stent, when expanded, will engage the lumen wall. The location is selected so the stent 6 is positioned beyond the occlusion 40 but not too close to the end 47 of the bile duct. The marker 11 indicates the position of the proximal end of the stent in the expanded position and is such that the proximal end of the prosthesis will engage healthy tissue over a length of at least 1 cm. Where possible the stent is centered, based on the fully expanded length indicated by markers 11 , 13 , about the obstruction. The marker 9 indicates the proximal end of the stent when the stent is in the fully compact form, which has an overall length, L 6 , about 10 cm.
Referring to FIG. 2 b , the sheath is retracted in one continuous motion. (After the retraction begins in this embodiment, the sheath cannot be extended distally without catching on the expanded portions of the stent and possibly pushing the stent distally off of the members 16 .) With the sheath 8 partially withdrawn, (arrow 20 ), portions 18 of the prosthesis expand (arrow 21 ), although not to full expanded diameter. The end loops 10 of the prosthesis are maintained in the compact state and without axial movement, by the members 16 which deflect outward slightly (arrows 23 ) when the sheath is removed. With the distal end of the stent being held axially by members 16 , the friction between the inner wall of the sheath 8 and the portions of the prosthesis covered by the sheath places the stent under tension, causing the prosthesis to be elastically lengthened slightly (arrow 31 ) to a length, L 6 ′, about 10.2-10.4 cm. The lengthening of the prosthesis has a simultaneous effect of reducing the radial force the stent exerts on the wall of the sheath and, therefore, the frictional force between the inner wall of the sheath and the stent, allowing a smoother retraction of the sheath with less axial force.
Referring to FIG. 2 c, as the sheath retraction continues, proximally beyond about 60% of the distance between markers 9 and 13 , the frictional force between the stent and the wall of the sheath is overcome by the elastic forces of the stent, removing the tension on the stent, and causing the distal end of the stent to relax distally (arrow 23 ). As illustrated, the relaxation of the largely independent knit rows proceeds from distal portions to proximal portions, with more distal portions expanding (arrows 25 ) to full diameter and engaging tissue. The most distal end, including the end loops, remains compact and axially stable.
Referring to FIG. 2 d, after sheath retraction continues but usually to a point less than marker 9 , the proximal end of the expanding (arrows 25 ) and contracting (arrow 23 ) prosthesis exits the sheath and engages the lumen wall, forcing open the lumen to its normal diameter and firmly anchoring the stent so that it resists axial motion. (In some cases, the stent opens the lumen over an extended period of time.) The end loops 10 remain compact and axially stable, owing to the strands 16 , as the elastic forces relax during the expansion of the proximal portions. The stent in this condition has a shorter length, L 6 ″, about 6 cm.
Referring to FIG. 2 e, the prosthesis is released from the catheter by drawing the catheter proximally (arrow 27 ), which causes the end loops to be positioned at more distal positions along the members 16 , until the radial force of the prosthesis causes the members to deflect outwardly (arrows 29 ), releasing the end loops from the members on catheter body, so the end loops expand to full diameter. Since the stent has been substantially relaxed during expansion of proximal portions, the end loops engage the lumen wall at the desired axial location, without substantial elastic rebound axially. After the end loops are released from the members, the free ends of the members deflect back to their rest positions closer to the taper 34 .
Referring to FIG. 2 f, the catheter is then removed from the body, leaving the prosthesis properly positioned.
Other Embodiments
Many other embodiments are possible. Other types of stents, e.g., nonknitted stents, such as woven stents, can be used. The engagement of the distal end of the stent may be achieved by other arrangements, beside the openings in the stent wall and wires illustrated above. For example, the systems could include a separate member for holding the distal end of the stent axially and a separate member for holding the distal end of the stent radially compact. The separate members may be separately actuatable. While the systems discussed above provide particular advantages when positioning self-expanding stents in that sheath retraction is made easier, advantages, such as accurate placement, can be gained with other stents, such as non-self-expanding, plastically deformable type stents. The systems can be sized and configured for use in various body lumens, such as the biliary tree or blood vessels, or any other lumen where accurate location of a stent is desired, e.g., when the occlusion is adjacent a side branch.
Still other embodiments are in the following claims. | This invention provides smooth delivery and accurate positioning of prostheses in the body. In embodiments, systems are provided that include elongate members extending generally along the axis of a supporting catheter to a free ends. The elongate members extend through openings in the prosthesis to maintain the position of the prosthesis on the catheter. The prosthesis can be released from the catheter by relative axial motion of the catheter and the elongate members such that the free ends are removed from the openings in the prosthesis. In embodiments, the elongate members hold the distal end of a self-expanding stent at a desired axial location and in radial compaction as a restraining sheath is withdrawn. The friction between the sheath and stent puts the stent under tension, which reduces the radial force on the sheath wall, allowing smoother retraction. Proximal portions of the stent radially expand and axially shorten. The distal end, however, is maintained at the desired axial location and released from the catheter to contact the body lumen wall without substantial axial shortening. | 0 |
FIELD OF THE INVENTION
This invention relates to a multi-purpose recreational facility, and in particular a single facility which combines the features of both an ice rink and an aquatic facility. The invention includes methods for temporarily or permanently converting ice rinks to aquatic facilities, and vice versa.
BACKGROUND OF THE INVENTION
The need for aquatic recreation has increased over the last 30 years. Experts are seeing a growing trend towards leisure swimming and aqua fitness, rather than laps and diving which requires traditional rectangular pools, with a large deep end. Unfortunately, existing pools are not designed or capable of meeting these new uses as well as conventional swimming activities. In addition, communities need to provide ice rinks to meet the present and future needs of the various ice user groups (hockey, figure skating, speed skating, leisure skating, etc.).
The capital cost of traditional pools and ice rinks is often a major stumbling block for communities. Furthermore, conventional ice rinks and pools are expensive to operate and therefore most communities or owners operate at a substantial loss, in trying to provide these recreational services.
Finally, available land for construction is often limited. There are also weather, liability and vandalism problems associated with outdoor pools. The conventional designs are limited in use and appeal and the obligation of providing recreational services for all user groups (elderly, handicapped, minorities, children, etc), places a tremendous burden on communities and private owners.
Conventionally designed single purpose facilities cannot cost effectively meet the present or changing needs of the entire community. Therefore, there exists a need for alternative designs of ice rinks and pools.
A single, multi-purpose facility that can function as both an ice rink and a pool, depending upon the needs at a particular time of the facility operator, is therefore an ideal solution to many of the economic problems associated with single function facilities.
It is known that the greatest demand for skating and hockey is usually during the winter, spring and fall. Therefore, ice rinks typically have little or no activity during the warmer months. By comparison, the greatest demand for aquatic activities is typically during the summer season (even though most indoor pools operate year round). Therefore, a year round multi-purpose facility that can provide both of these activities, is desirable from both a programming and an operating standpoint.
In certain jurisdictions, there exist an abundance of pools and very few ice rinks. To meet the temporary, periodic demand for skating, a way of converting the indoor pool to an ice rink has already been developed. This system comprises erecting a temporary, elevated floor, rink boards and refrigeration system above the pool area. The floor and ice slab for the ice rink are supported by beams, posts, decking and scaffolding above the swimming pool structure.
However, to erect such a structure requires a large amount of time, labour, materials and money. Furthermore, much of the material used to erect the structure is single purpose, cannot be reused, and must be discarded. Also there is a significant amount of time required when the facility is being changed from an ice rink mode to an aquatic mode, and vice versa. Thus such a facility will typically be unusable for a significant period of time.
Heretofore, no attempt has been made to convert an ice rink (indoor or outdoor) to a facility which also can operate as pool or aquatic facility, utilizing compatible, reusable, interchangeable and common components and systems.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention there is provided a multi-purpose recreational facility comprising: a base to support one of a layer of frozen fluid and a pre-selected quantity of fluid; an upstanding wall surrounding said base, and having an opening; a fluid retaining membrane extending from said wall onto said base; a door moveable between an open position whereat said door does not block said opening and a closed position whereat said door blocks said opening, and said wall, said door, said base and said membrane define a tank to retain said quantity of fluid; and a refrigeration system to freeze said layer of frozen fluid on said base.
In accordance with another aspect of the present invention there is provided a multipurpose recreational facility comprising: a base to support one of a layer of frozen fluid and a pre-selected quantity of fluid; an upstanding wall surrounding said base, said wall defining an enclosure, such that said wall and said base define a tank, said wall being adapted to retain said quantity of fluid within said tank; a waterproof seal between said base and said wall; and a heating and refrigeration system comprising a heat exchanger in thermal communication with said base, said heat exchanger operable to heat said quantity of liquid and to freeze said layer of frozen fluid on said base.
According to another aspect of the invention, there is provided a multi-purpose recreational facility comprising: an impervious base adapted to support one of a layer of ice and a pre-selected quantity of fluid; an impervious wall upstanding from and secured to said base, said wall defining an enclosure such that said wall and said base define a tank, said wall and base being adapted to retain said quantity of fluid within said tank; a first pipe system having an input end and an output end, said first pipe system located proximate said base and being in fluid communication with a refrigeration and heating system; said refrigeration and heating system comprising a second pipe system having an input end and an output end, both input and output ends being in fluid communication with the output and input ends respectively of said first pipe system, whereby said first and second pipe systems form a pipe circuit; a secondary refrigerant disposed with said pipe circuit; a heat exchanger disposed in said second pipe system for removing heat from said secondary refrigerant carried within said pipe circuit; a pump disposed in said second pipe system and being adapted to pump said secondary refrigerant through said pipe circuit; a heater disposed in said second pipe system for heating said secondary refrigerant carried within said pipe circuit; a valve means for alternating the flow of said secondary refrigerant either along a first path through said heat exchanger or along a second path through said heater; whereby when secondary refrigerant is driven along said first path, said secondary refrigerant will pass through said heat exchanger and then through said first pipe system to freeze, and maintain frozen, a layer of ice supported on said base, and when said secondary refrigerant is driven along said second path said secondary refrigerant will pass through said heater and said first pipe system to heat a quantity of fluid supported on said base and retained in said tank.
According to a further aspect of the invention, there is provided a method of converting an ice rink to a multi-purpose recreational facility, said ice rink comprising: a base adapted to support a layer of ice; a wall upstanding from and secured to said base, said wall defining an enclosure, said wall and said base defining a tank; said method comprising the following steps: increasing the load bearing capacity of said base such that base can support a quantity of water; strengthening the wall so that said tank can support a quantity of fluid in said tank; installing an impervious fluid retaining membrane to cover an upper surface of said base and an inward facing surface of said wall; sealing all openings in said wall water tight.
According to a further aspect of the invention, there is provided a multi-purpose recreational facility comprising: a base adapted to support a pre-selected quantity of fluid; a wall upstanding from and secured to said base, said wall defining an enclosure, such that said wall and said base define a tank, said wall and base being adapted to retain said quantity of liquid within said tank; at least one modular wall component having an interior cavity, said wall component having a sealable opening for permitting a ballast material to be put in and taken out of said cavity; wherein when said tank is filled with said quantity of liquid, and said cavity of said modular component is filled with said ballast material, said modular section may be received into said tank and remain in situ in said tank.
The present inventors have found it is possible to combine both an ice rink and an aquatic facility into a single multi-purpose recreational facility. A new ice rink can be created or an existing ice rink can be modified, to create a structure which permits a relatively easy and cost effective conversion from ice rink to a pool (aquatic facility), and vice versa. The period of time during which the facility can not be used during changeovers between pool and ice rink modes, will be reduced.
This multi-purpose facility is flexible enough in design to meet the changing recreational needs of the community, yet still provides the best operating conditions for whatever activity is in place. Furthermore, this multi-purpose recreational facility does not compromise quality (water, ice and environment) in order to achieve this result. Proper conditions are maintained and often improved for skating and aquatic activities.
This multi-purpose recreational facility also permits the shared design, use, infrastructure and cost for such items as heating, air conditioning, ventilation, dehumidification, building envelope, land lighting, water, electricity, sewage, storage, change rooms, washrooms, parking lot, concession area, utilities and services, showers, lobby area, mechanical/electrical rooms offices and stands. This translates into substantially reduced capital and operating costs in comparison to two stand alone conventional rink and pool complexes.
In such a recreational facility, national and international swimming events (50 m pool) may be held, without having the initial or ongoing financial burden associated with conventional designs. The present inventors have also discovered a way to easily modify the multi-purpose facility so that modular components can be added within the rink structure to create lazy rivers, islands, lap pools, bridges, decks, splash areas, water parks, slides and play features.
A rink base (concrete, sand, ground, etc.) may be adapted to support both a layer of ice and water. Furthermore, a membrane can be incorporated into the floor and rink boards to create an impervious tank for the water. The rink dasher board or wall system and gates can be modified to create a sealed enclosure which can withstand the force from the static and dynamic loads (water, people, equipment, decking, etc.). The wall may also be adapted to provide a means and support for the pool water recirculation system.
Further, the refrigeration piping and plant can be modified to provide both cooling and heating for the pool water or rink ice.
A permanent white membrane may be incorporated into the boards and floor design and with the added use of demineralized flood water (which produces clear ice), the problems and costs associated with painting the ice white would be eliminated, ice quality would be drastically improved and energy/operating costs substantially reduced. In addition, a white membrane would provide better illumination levels and greater visibility (due to its highly reflective properties), for both the pool and rink activities.
Modular wall, decking and support components can be added to the interior of the rink board enclosure to create changes in the standard open oval rink shapes (85 ft×185 ft, 85 ft×200 ft, 30 m×60 m, etc.). Using these components, the tanked rink can be modified to the owner's specifications. For example, these components could be used to create lazy rivers, islands, splash areas, decks, slides and bridges. These interlocking and compatible components can be changed or added to at any time to create new aquatic features and dimensions. The facility is not restricted to one standard design or function.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be more clearly understood after reference to the following detailed specification read in conjunction with the drawings, describing and illustrating example embodiments of the invention.
FIG. 1 is a perspective view of part of a multi-purpose recreational facility made in accordance with one embodiment of the invention.
FIG. 1a is a side sectional view through the recreational facility of FIG. 1.
FIG. 2 is a perspective view of another part of the multi-purpose facility of FIG. 1.
FIG. 3 is a perspective view of part of a wall of a multi-purpose recreational facility in accordance with an embodiment of the invention.
FIG. 4(a) is a plan view of the multi-purpose recreational facility of FIG. 1.
FIG. 4(b) is a sectional, perspective view of a multi-purpose recreational facility in accordance with an embodiment of the invention operating as an ice rink.
FIG. 4(c) is another sectional, perspective view of the multi-purpose facility of FIG. 4(b) operating as an aquatic facility.
FIG. 5 is a schematic drawing of the heating and refrigeration system for a multi-purpose recreational facility in accordance with an embodiment of the invention.
FIG. 6 is a perspective view from above of part of a modular wall section of the multi-purpose recreational facility of FIG. 1.
FIG. 6a is a more detailed perspective view of part of the modular wall section of FIG. 6.
FIG. 7 is a perspective view of the part of the modular wall section of FIG. 6 shown in combination with other modular components, in accordance with an embodiment of the invention.
FIG. 8 is a plan view of a recreational facility constructed in accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
With reference to FIGS. 1, 1a and 4a, parts of a recreational facility generally designated 10 are illustrated. Recreational facility 10 may or may not include an enclosure such as a concrete or wood framed building. In FIG. 4a the outline of an enclosure 11 is shown which may be desirable in certain geographical locations, and covers and contains an ice rink/pool structure 29.
FIG. 1 shows recreational facility 10 in its ice rink mode; FIGS. 1a and 4a illustrate the features of structure 29 in both the ice rink and pool (aquatic) modes of the facility concurrently. Although facility 10 will operate only in one mode at any given time, it can easily be changed from one mode to another.
Structure 29 has a base 12 and an upstanding wall or a dasher board structure 14, which is secured to base 12. Base 12 is typically of concrete, or possibly sand. Wall 14 defines an enclosure 11 (see FIG. 4) and will in most cases be configured in a standard oval-like shape. Wall 14 together with base 12, defines a tank 16 for retaining a quantity of liquid 18. Liquid 18 will usually be water combined with water treatment additives, such as chlorine.
A longitudinal sill member 19 extends along the top of wall 14. Sill may be made from a one inch thick strip or strips of solid plastic. In the pool mode shown in FIG. 1, mounted on top of sill 19 are a plurality of transparent, tempered glass or plexiglass sheets 25, which are connected together by conventional means such as H-connectors. Sheets 25 are removable. A footing (not shown) may be required at the base of wall 14 to carry the load on the wall.
Base 12 must be able to support the weight of liquid 18 of a height H. Further, the load bearing capacity of the substrate on which base 12 rests may need to be increased if the substrate cannot carry the load of the liquid 18. For example, piles may be needed to support base 12 in some circumstances. Whether constructing a structure 29 from new, or retrofitting an existing ice rink, the base must be of such strength to support the weight of liquid 18, when the structure 29 operates in pool mode.
Wall 14 may be made of wood and/or metal construction, employing a plurality of stringers 13a and posts 13b (typically made from hollow metal tubing), covered with a material such as plywood sheets, to provide a continuous inward facing surface 20 and an outward facing surface 22. Alternatively, wall 14 may be made of concrete.
Referring to FIGS. 1 and 1a, wall 14 is mechanically secured to base 12 by conventional attachment means such as steel bolts and anchor plates collectively identified as 24.
When operating in pool mode, as depicted in FIG. 3, a plurality of brace members 26, are spaced along the outer face of wall 14, and each brace is secured to wall 14 at a connection such as connection point 28. Braces 26 are connected at 30 to one or more load bearing devices such as an angle support 30a, so that braces 26 can withstand both compression and bending loads applied thereto by wall 14. Thus braces 26 act to support wall 14 which, when structure 29 is in the pool mode, will be heavily loaded when tank 16 is filled to height H with liquid 18. In addition to static loading on the wall 14, there may also be appreciable dynamic forces acting on wall 14 when in pool mode, resulting for example from movement of the water created by pool users. This will have to be accounted for in designing braces 26. The position of connection point 28 may be chosen so as to minimize bending on wall 14. For example, when a quantity of fluid 18 of height H is held in tank 16, applying a bracing load at a distance of H/3 from the bottom will minimize bending in the wall. Braces 26 are preferably easily disconnected from the wall support positions, so that when in the ice rink mode, they may be readily removed.
Alternate methods of reinforcing wall 14 are possible. For example, wall 14 may be constructed in a cantilever fashion, wherein wall 14 extends into the substrate and acts like a cantilever beam.
As shown in FIGS. 1 and 1a, a fluid retaining, impervious membrane 15 covers the upward facing surface 13 of base 12, and covers the inward facing surface 20 of wall 14. Membrane 15 is preferably a durable, 60 mm thick sheet of substantially white coloured PVC, although other materials are suitable. Membrane 15 is secured to wall 14 by a mechanical fastener 17 which passes from top sill 19, through the membrane and into wall 14. Thus membrane 15 is secured by the pinching action between wall 14 and sill 19.
As seen in FIG. 1, membrane 15 extends from between the top plate of wall 14 and sill 19 on the outside face of wall 14. The outer edge of membrane 15 is secured to a rod member 15a that may be made from a material such as PVC or steel and have a mechanism for attaching the rod to the outside face of the wall when the structure 29 is in ice rink mode. When it is desired to change from ice rink mode to pool mode, rod 15a can be released form attachment to wall 14, for use in lining a gutter trough, as described below.
It is possible to eliminate membrane 15 and instead seal the base in another manner, such as by sealing the concrete with a plurality of impervious tiles. In such a facility, a separate fluid retaining mechanism is then needed for wall 14 so that tank will retain the fluid, without leakage. Furthermore, a waterproof seal would be required between the base and the wall.
Membrane 15 may be formed in parts which can be connected together at and by a waterproof seal. A suitable such seal would be a waterproof zipper mechanism such as that used in the construction of scuba suits. Thus it may be appropriate to provide for a connection proximate where the wall and base meet, so that the portion of membrane 15 covering inner surface 20, can be removed.
Also, membrane 15 need not extend up the entire inner surface 20, or even any part of inner surface 20 of wall 14, but may be used only to cover and seal base 12. Again, in such a case, a separate fluid retaining mechanism is needed for wall 14 and a waterproof seal is required between the base and wall.
A face board is comprised of a plurality of face board sections 21 each positioned in face to face relationship with the membrane 15. Thus the portion of membrane 15 covering inner surface 20 of wall 14 is sandwiched between wall 14 and sections 21. Face board sections 21 may be formed from plywood or a similar material but preferably each has an inward facing surface made of a layer of plastic chosen for its ability to retain a white coloured appearance. Other colours may in certain circumstances be desirable. Sections 21 substantially abut each other and are connected with standard connectors such as H-clips. Thus the face board will protect that portion of the membrane covering inner surface 20 of wall 14. Each section 21 has a top edge 21a which is received within a longitudinally extending groove 25 in sill 19. The bottom edge 21b is held in place by a kick plate or kick strip 27. Membrane 15 passes between the bottom of kick plate 27 and the upper surface of base 12. Face board sections may be made readily removable, for example by providing for a kick plate 27 which can be easily removed.
Mechanical fasteners 33 pass from kick plate 27 through membrane 15 into wall 14 and are provided with gaskets to provide a waterproof seal where they pass through membrane 15. In some circumstances a kick plate may not be needed and mechanical fasteners 33 may also not need to be employed.
Wall 14, although defining an enclosure 11, is not uninterrupted. An example of such a discontinuity is shown in FIG. 2, where an opening 36 is shown. Typically in such a facility there will be more than one such opening. A door 38, shown exploded away from opening 36 is adapted to block opening 36. A hinge 40 may be provided on door 38, to permit opening of door 36 outwardly of the tank, from a blocking relationship with the opening, to an unblocked relationship therewith. A door 38 may replace a standard ice rink door, when tank 16 is to be filled with liquid.
However, a mechanism is needed to secure the door in the blocked position when the facility is in pool mode and tank 16 is filled with liquid 18. The wall 14 at opening 36, and door 38 may be provided with bolts, to bolt the door to the wall when the tank is to be filled. Alternatively, when desiring to fill tank 16 with fluid 18, a door may be permanently welded in place.
Door 38 is typically formed of a steel and/or wood construction of posts and stringers with outer layers of plywood, in a manner similar to the rest of wall 10. The surface 50 will be finished to match the face boards. Door 38 has a seal 42 consisting of a continuous neoprene gasket located at the front peripheral edges of side faces 44,46 and bottom face 48. Thus when door 38 is positioned in opening 36 a waterproof seal is provided between the door and wall 14. Inward facing surface 50 of door 38 is impervious. The imperviousness may be effected by providing a PVC membrane layer beneath the layer of material of which surface 50 is a part.
It is also possible to provide for a waterproof connection of the zipper type referred to above, to connect the membrane 15 to a corresponding section of PVC material formed in the door, thus in effect providing for a continuous PVC membrane.
Liquid can be added to or drained from tank 16 by a variety of standard methods. The tank may be provided with a sealed drain pipe to remove liquid. Alternatively, a pump may be employed to remove the liquid.
Preferably, disposed within base 12, are a plurality of spaced, interconnected pipes 32, which are arranged in parallel longitudinal relation to each other. Pipes 32 are made from PVC or another material suitable for carrying both a heated and cooled secondary refrigerant such as brine or glycol. When a cooled secondary refrigerant is passed through pipes 32, a layer of ice 34 may be formed and maintained on the upper surface of membrane 15.
FIG. 4a shows for contrast, in a single illustration, recreational facility 10 in both pool mode and ice rink mode. However, as explained previously, the facility will only operate in one mode at any given time.
Referring to FIG. 4b, the ice rink mode of FIG. 1 is shown in a sectional perspective view.
In FIGS. 3 and 4c, the facility 10 is shown in its pool mode wherein the transparent sheets 25 mounted on top sills 19 have been removed. In their place, a pool decking 90 has been mounted above upper sill 19 of wall 14 and is partly supported on wall 14. Pool decking 90 spans the gap between wall 14 and a supporting wall 91 is erected at a distance from wall 14. Decking 90 circumscribes the entire wall 14 to permit people to more readily access the tank 16.
A series of deck supports 92 provide for a gap between deck 90 and upper sill 19. The gap permits liquid spillage flowing out of tank 16 to be directed to a gutter or trough 95. Gutter 95 will carry spillage away either to be disposal or to be filtered and recycled back into tank 16. As illustrated in FIG. 3, membrane 15 extends continuously from between the top plate of wall 14 and sill 19 and extends into the trough 95 to provide an water proof lining therefore. The rod member 15a around which the outer edge of membrane 15 is secured, may be attached to an upper edge of the trough 95, or even to the underside of decking 90, for example by screws though rod 15a into decking 90. As gutter trough 95 is thereby imperviously with the membrane, it need not necessarily be made from a completely impervious material and be completely water tight, itself.
Gutter trough 95 may be integrally formed with decking 90 or mechanically attached thereto. Alternatively, gutter 95 may be positioned with a flange which extend underneath membrane 15, between top sill 19 and the top plate of wall 14. When decking 90 is in place, the load thereof may be sufficient to secure both the outer portion of membrane 15 and gutter 95 in position.
A filtered water return pipe 31a may be introduced into and pass through wall 14 to provide for water filtration of liquid 18 held in tank 16. Of course a water tight connection is required where the pipe passes through membrane 15. The pipe is connected to a standard water filtration system used for a swimming pool.
From the foregoing it will be readily appreciated that the change from ice rink mode to pool mode, does not require a great degree of structural changes. Transparent panels 25 are replaced by decking 90 supported by support wall 91 and wall 14. Braces 26 are erected to provide support for wall 14. All openings 36 are sealed with doors of the type 38 or the like. The layer of ice is replaced by liquid to a height H in tank 16, by a conventional pumping device (not shown). The membrane 15 remains in place in tank 16, the outer edge is positioned as a liner in a trough 95. Some of the changes are readily apparent by comparing FIGS. 4(b) and 4(c). To change back to ice rink mode, the foregoing changes are carried out in reverse and again membrane 15 remains in place.
Unlike other recreational facilities, facility 10 has an integrated system which serves both to heat the water or liquid when in pool mode, and to create and maintain a layer of ice on the base when in rink mode. An existing ice rinks refrigeration system can readily be altered to integrate therewith a heating system, utilizing common elements.
FIG. 5 is a schematic layout of an integrated heating and refrigeration system for recreational facility 10. Pipes 32 are interconnected and have a common inlet 50 and common outlet 52. A pipe 66 is connected at one end to outlet 52, and at the other end to the intake of a pump 84. Pump 84 has an outlet connected to one end of a pipe 62. The other end of pipe 62 joins with pipe 64 and pipe 60 at a T-junction 86. A valve 70 is disposed in pipe 64 and a valve 72 is disposed in pipe 72. One end of pipe 64 is connected to T-junction 86, the other end to an input of a heater 80. Heater 80 is adapted to be able to heat a secondary refrigerant and may be any conventional type of heater such as a boiler, solar, etc. The output of heater 80 is connected to one end of pipe 56. The other end of pipe 56 forms a T-junction with an end of a pipe 58 and an end of pipe 54.
Pipe 60 has one end connected to T-junction 86, the other end of which is connected to the input of a heat exchanger 82. Heat exchanger 82 is of conventional type and would employ a primary refrigerant such as ammonia, to cool the secondary refrigerant. The output of the heat exchanger 82 is connected to one end of pipe 58, the other end of pipe 58 is connected to the T-junction 88. A valve 76 is disposed in pipe 58 and a valve 74 is disposed in pipe 56. Finally, one end of pipe 54 is connected to T-junction 88, the other end is connected to the input 50.
Pipes 32, 66, 62, 64, 60, 58 and 54, which may be 1 1/2 inch PVC pipes, together form a closed circuit and permit the flow of a secondary refrigerant such as brine or glycol therethrough. Pump 84 drives the secondary refrigerant in one of the paths shown in FIG. 5 by the arrows. The particular path of the secondary refrigerant is determined by the valves which are open and which are closed.
When it is desired to operate the facility 10 as an ice rink (i.e. in ice rink mode), any large quantity of fluid 18 in tank 16 is drained. A layer of fluid, typically water, is placed on the upper surface of membrane 15. Valves 74 and 70 are closed, valves 76 and 72 are opened. When the heat exchanger 82 is engaged and pump 84 activated, the secondary refrigerant in the pipes will be circulated through the heat exchanger, cooled, and passed through pipes 32 in base 12. This will cool and freeze the layer of fluid to form a layer of ice 34. Due to the white colour of the membrane, the ice will appear white in colour.
When it is desired to convert the facility to an aquatic facility (i.e. pool mode), the heat exchanger is disengaged and valves 72 and 76 closed. Valves 70 and 74 are opened and pump 84 is activated. The heater is engaged with the result that the secondary refrigerant is driven through the heater 80 where it is heated, and then circulated through pipes 32.
The heated secondary refrigerant will thaw the layer of ice, and that liquid can be drained. The warming of the base will also have the effect of thawing the adjacent substrate. The result is that the base will not be cold to the touch, and will be suitable for contact with a person's skin.
The tank 16 is filled with fluid to height H, and the heated base will heat the fluid 18 in tank 16.
An existing ice rink may be converted to such a multi-purpose facility by (1) ensuring the base and substrate can carry the load and if necessary increasing the load bearing capacity; (2) providing the necessary wall reinforcement; (3) installing an impervious fluid retaining membrane; (4) providing a heating system; (5) providing necessary sealing of openings in the enclosure.
With reference to FIGS. 6 and 6a, a wall portion 100 of a modular drop-in wall section for the facility 10 is shown. Wall portion 100 comprises a straight or planar wall section 102 which is connected to a pair of support columns 106 and 108. Also extending from support column 108 is a curved wall section 104. Wall sections 102 and 104 are releasably connected to the support columns by a key and key-way slot system (not shown).
As shown in FIG. 7 modular wall section 100 is combined with a pair of drop-in support columns 110 and 112 to support a deck section 114. The wall section 100 and the support columns are ideally all made from a material such as fiberglass reinforced plastic ("FRP"), a plastic stainless steel, galvanized aluminum, or a lightweight concrete, which are resistant to chlorine degradation and also resistant to ultra-violet radiation. The wall section 100 and the support columns are positioned within the boundaries of the facility 10 when it is in its pool mode and filled with water.
The modular sections are utilized when the structure 29 is in pool mode. To make the modular sections easier to handle for placement into and movement out of the structure 29, wall sections and support columns may be formed of a hollow rigid material such as described above (FRP, etc.). The hollow modular components of the wall section as shown in FIG. 6a can each be placed in position within tank 16 as desired, and then filled with a ballast material such as sand gravel. Water may also be used in a ballast, particularly when the ballast fills the support columns and/or wall sections, to a height above height H of the water in tank 16. The ballast material must be sufficiently dense to ensure that the modular components do not float, and preferably will be dense enough to ensure that a reasonably large frictional force is developed, to maintain stability of the modular components both vertically and horizontally when in use.
FIG. 6a shows a modular wall section 118 which has removable caps 120 which permits a suitable ballast material with sufficient fluidity to be pumped into and out of the modular section 118.
Column 108 may be provided with apertures 109 which are formed as stairway treads to permit a person to get out of the water and onto decking 114.
In use in tank 16, filled with liquid, each of the modular components will have liquid on both sides thereof. Thus the static horizontal loading on each side of the components will be equal. With respect to any dynamic forces acting on a component, although unbalanced, it will not typically be of a magnitude to overcome the frictional resistance of the bottom of the component against the base. Moreover, the modular components may be arranged such that they are interconnected with outer wall 14, to provide the necessary degree of horizontal resistance.
The use of modular components provides great flexibility in creating a facility 10, which in pool mode configuration of structure 19, may have configurations only limited by the availability of the modular component's on hand, and the creativity of the designers. As is shown in FIG. 8, within the confines of a standard ice rink configuration, by use of combinations of modular components such as those described above in addition to liberal use of decking, various aquatic features may be provided such as a circumscribing lazy river 120 and a 25 m swimming pool 124, a water slide 126 all interconnected by decking 130. Outer decking 190 is interconnected to decking 130 by bridges 132 and 134. Decking 130 is supported appropriately by support columns, such as those described above. The inner pool structure is enclosed by a conventional building 111.
It will be appreciated that many variations from the foregoing description of preferred embodiments are possible, and are contemplated to be within the scope of the invention as hereinafter claimed. | An ice rink and an aquatic facility are combined into a single multi-purpose recreational facility. A new ice rink can be created or an existing ice rink can be modified. This multi-purpose recreational facility also permits the shared design, use, infrastructure and cost. The multi-purpose facility has modular components that can be added within the rink structure to create lazy rivers, islands, lap pools, bridges, decks, splash areas, water parks, slides and play features. A rink base may be adapted to support both a layer of ice and water. Furthermore, a membrane can be incorporated into the floor and rink boards to create an impervious tank for the water. The rink dasher board or wall system and gates can be modified to create a sealed enclosure which can withstand the force from the static and dynamic loads (water, people, equipment, decking, etc.). The wall may also be adapted to provide a means and support for the pool water recirculation system. Further, the refrigeration piping and plant can be modified to provide both cooling and heating for the pool water or rink ice. | 5 |
[0001] This is a divisional application of an U.S. application Ser. No. 10/639,489, filed on Aug. 13, 2003, which is now pending.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a modular power supply system with bypass and the method of switching output modes, in particular to an AC power supply system that is capable of providing fault-tolerant protection for critical loads or loads requiring high power output.
[0004] 2. Description of Related Arts
[0005] Computers and networking have become essential tools for enhancing the economic and technological development in many countries. To keep the operation of computers and networks working in normal condition, there has to be a continuous supply of electrical power. Even a brief power interrupt could cause massive loss of data for data processing equipment and breakdown of data communication systems. Companies and individual users alike realize the need of maintaining a reliable source of electricity and see the benefits of installing an uninterruptible power supply, to protect their installation and the operation results therefrom. Therefore, the demand for uninterruptible power supply is increasing steadily.
[0006] The uninterruptible power supply (UPS) systems can be generally classified as on-line and off-line types. For off-line UPS, power input is normally set in a main-line mode with the power input directly connected to the main-line through a bypass, and only when a power break occurs over the main-line, the power supply is switched to a battery output mode drawing the power from a battery through an inverter. The design of the off-line UPS, though simple, does not provide power regulation for the line input, and longer time is needed for detecting any power break over the main-line and subsequently switching to the battery output mode.
[0007] For the on-line UPS, the AC power output is always fed through an inverter with signal filtering, in both the main-line and battery output modes. Since on-line UPS does not need to switch the output path between the bypass and inverter, the mode switching process can be effected with shorter time, whereas the switching usually takes about 10 ms for off-line UPS. Since the on-line UPS can offer a more reliable power supply, the demand for this type of UPS is increasing steadily.
[0008] The architecture of an on-line UPS comprises an AC/DC converter, a DC/DC converter, a DC/AC inverter, a bypass circuit and a charger. In a normal condition, the power input is fed through the AC/DC converter to change from AC to DC, and then further fed through the DC/AC inverter to generate AC power output. When the UPS is down or experience overloading, the UPS will be instantly switched to the bypass mode for direct connection of the load and the main power, such that continuous power supply can be maintained without interruption. The battery and the main-line can be connected in parallel as the power input for the DC/AC inverter, and the voltage output of the battery through a DC/DC converter can be designed to be lower than that from the main-line through the AC/DC converter. In the normal supply conditions, the power supply comes from the main-line, but when the main power is not available, the UPS will be automatically switched to the battery output mode, such that the current from the battery will pass through the DC/DC converter boosting the DC output voltage, and then further through an inverter to AC output for the load. Besides, the UPS has an additional function of protecting the electrical equipment from high voltage spikes during lightning strikes.
[0009] Over the years, the storage capacity and reliability of UPS has upgraded considerably. New power systems have taken care of scalability and flexibility in their designs.
[0010] To fill the increasing demands and make the power supply more reliable, a plurality of UPS modules is connected in parallel for parallel operation. When a UPS module is down, the control system should be able to isolate the failing UPS module, without affecting other parallel UPS modules still supplying the load. This fault tolerant design provides a more reliable power source for critical loads or loads with high power requirements. Furthermore, with modular UPS the power supply system can be easily upgraded or maintained operated if required, simply by increasing the number of UPS modules or making adjustments to fill different needs of power users.
[0011] For a standalone UPS, in case of overloading or equipment failure, the UPS is switched to the bypass mode to prevent power interruption to the load. If the fault occurs on one of the UPS modules in a conventional modular power supply system, the system cannot isolate a single failing UPS module from other parallel UPS, instead it will order all UPS modules to switch to the bypass mode as a safety measure.
[0012] There is another problem with the mutual interference, which may cause some UPSs to switch erroneously, or fail to switch at all, resulting in the anomalous parallel connection between the inverters and the main-line. This could lead to a situation of system breakdown. It is therefore necessary to find a way to enhance the system reliability in synchronous switching to or back from bypass mode. In addition, it is necessary to lower the production costs with simple circuit implementation.
[0013] In one prior art, U.S. Pat. No. 6,292,379 B1, a method of synchronous switching of UPS modules to bypass is proposed. Each UPS module paralleled in the system is composed of an inverter, a bypass circuit and a controller. All UPS modules are interconnected by a high-speed communication bus and a logic state control line forming a network. When any module in the system is about to switch to the bypass mode, the module first has to gain control of a sync-line, an extra synchronization control line, by posting a request onto the network through the high speed communication bus. After obtaining the permission the module notifies other modules of the impending switch to the bypass mode, and then sends a toggle signal over the sync-line to generate a top priority interrupt forcing all modules to be switched to the bypass mode simultaneously.
[0014] This prior art has demonstrated the feasibility of switching all UPS modules in the modular power supply system to the bypass mode simultaneously, just like a standalone UPS, in case of overloading or equipment failure. Although this technique can enhance the reliability of parallel UPS modules, it only provides a fundamental approach to the issue at hand.
[0015] The prior art has not considered the following issues:
[0016] (1) Sending a toggle signal over the extra sync-line for system synchronization can lead to false switching of UPS due to noise. As a result, the UPS modules in the modular power supply system may be operating in different modes, leading to the anomalous situation that the inverters parallel to the main-line voltage.
[0017] (2) When the toggle signal is sent over the sync-line to all UPS modules using a top priority interrupt, the normal operation of the CPU is paused by the interrupt signal, holding up the system resources for the sole purpose of switching a UPS module to the bypass mode. This method may be too costly for the system, as it is only necessary to isolate a failing UPS module in one of the rare situations when the operation of the UPS module is at fault, resulting in substantial waste of CPU resources and extra costs for the synchronization line.
[0018] (3) The switching of all UPS modules to the bypass mode at one time just because of the failure of a single unit in the system is not reasonable and undesirable for critical loads or loads with high power requirement. For example, there are three UPS modules with a total capacity of 3000 VA sharing a load with the power requirement of 1000 VA. If one of the UPS modules is down, according to the logic of the prior art, all three UPS modules will be switched to the bypass mode simultaneously. If the main-line is not stable at that time, the operation of the load will be in jeopardy. Design on new UPSs allows the power out to be fed through the inverter in all possible conditions to enhance the overall reliability of the power supply, and only resorts to switch to the bypass mode as a last option.
[0019] (4) Possible damage from electric arcing during the switching action of the output relay: when a UPS is switched to the bypass mode, it is necessary to assure that the output relay toggles when the output voltage is at the zero crossing point, otherwise arcing is produced during the switching of the relay, which may force the relay to be reset to normal-closed or normal-open unexpectedly. In parallel modular power supply systems, any damage to the output relay in the module will result in the inverter and the main-line anomalously connected in parallel leading to a system breakdown.
[0020] The present invention has paid due consideration to the above mentioned elements to make the new modular power supply system more reliable and more efficient in using CPU resources, such that when a UPS module is down or overloaded, the system is able to isolate the failing UPS to prevent it from affecting other parallel UPS modules.
SUMMARY OF THE INVENTION
[0021] The main object of the present invention is to provide a method for managing the modular power supply system whereby any UPS module at fault can be isolated from other UPS modules in parallel operation. The mode switching in the present invention only employs a low order interrupt that could avoid halting of the normal operation for other UPS modules. The present invention thus provides enhanced system reliability and efficient control of parallel UPS operation.
[0022] To accomplish the above object each UPS module in the modular power supply system is provided with identical control logic for parallel processing and participation in an arbitration scheme to create a virtual control center (VCC) which is designed to control the operation of all parallel UPS modules.
[0023] Each UPS module is connected by a common high-speed communication line (HSCL) for inter-unit communication. Each UPS module is also connected by a common sync-clock-line (SCL), a control line originally embedded in the modular power supply system, for controlling the output phase from all inverters and the synchronous switching to the bypass output.
[0024] Each UPS module participates in an arbitration scheme over the UPS network through the HSCL to compete for possession of the VCC when the modular power supply system is initialized. When the requesting UPS module is granted possession of the VCC, all other UPS modules will send in their operating data for the system to determine whether any UPS module needs to be isolated from other parallel UPS modules.
[0025] If, for some reason, the original UPS module possessing the VCC disappears from the UPS network, it will automatically relinquish the VCC to a new UPS module that begins to assume the VCC in place of the original UPS module that may be down.
[0026] The above mentioned VCC takes control of the sync-clock-line, through which the VCC continuously sends out sync clock signals to synchronize the operation of all UPS modules connected over the UPS network. The control signals output by the VCC are used to synchronize the power output of all parallel UPS modules, such that the output voltage from each inverter (InvVolt) should correspond with the phase angle and frequency as the sync clocks when the switch command is issued by the VCC. Furthermore, the zero crossing points of the InvVolt should also correspond with the rising edge and falling edge of the sync clocks. The above-mentioned sync-clock-line is embedded in the system hardware for synchronizing the output voltage from all UPS modules connected over the UPS network. The embedded sync-clock-line is able to minimize the risks of mutual interference, as compared with the prior art in which an extra sync-line is used exclusively for controlling the synchronous switching to the bypass modes, thus increasing the risks of signal conflicts.
[0027] The synchronous switching of all UPS modules should be effected by an interrupt at the rising/falling edge of the sync clock, which allows all parallel UPS modules to receive the above signal at the same time for a synchronized switching between the inverter output and the bypass output.
[0028] A typical UPS module in accordance with the present invention comprises an AC/DC converter, a DC/DC converter, a charger, a bypass circuit and a DC/AC inverter.
[0029] The bypass circuit is formed by two stage relays, such that the total capacity of the bypass output of the system is the sum of the individual relay output of all parallel UPS modules. By means of the two-stage relay mechanism to isolate the failing UPS, the system of parallel UPS modules can be managed efficiently without affecting other parallel UPS modules.
[0030] 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
[0031] FIG. 1 is a block diagram of the architecture of the modular power supply system in accordance with the invention;
[0032] FIG. 2 is a schematic of the control circuits in a typical UPS module;
[0033] FIG. 3 is the logical flow of the operation initiated by a VCC for synchronous switching of all UPSs to the bypass mode;
[0034] FIG. 4 shows the signal waveforms of the output voltage signal from an inverter and the sync clocks when a switch command is issued by the VCC, both are in sync having the same phase angle and frequency;
[0035] FIG. 5 is the logical flow of an interrupt subroutine initiated by the non-VCC for synchronizing the switching from the inverter output to the bypass output;
[0036] FIG. 6 is the logical flow of operation initiated by the VCC for all UPSs to be switched back from the bypass output to the inverter output;
[0037] FIG. 7 is the logical flow of an interrupt subroutine initiated by the non-VCC for synchronizing the synchronous switching back from the bypass output back to the inverter output;
[0038] FIG. 8 is the interrupt subroutine executed by non-VCC at the falling edge of the sync clock.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0039] The present invention provides a method for managing a modular power supply system consisting of a plurality of uninterruptible power supply (UPS) modules ( 10 ) ( 101 ˜ 10 n ) connected in parallel. As shown in FIG. 1 , the input terminal of each UPS module ( 10 ) ( 101 ˜ 10 n ) is connected in parallel to a common system input or the main power, and the output terminal of each UPS module ( 10 ) ( 101 ˜ 10 n ) is also connected in parallel to an AC output bus. The input and output of the modular power supply system ( 10 ) are connected across by a manual-bypass switch ( 20 ) used for tuning and system installation. The manual-bypass switch ( 20 ) has an output capacity that should be equal to or larger than the maximum capacity of the system, and the manual-bypass switch ( 20 ) should be set to normal-open in normal condition.
[0040] The structure of each UPS module ( 10 ) includes (shown in FIG. 2 ):
[0041] an AC/DC converter ( 11 ) coupled to the output of an input filter for converting the line AC to DC;
[0042] a DC bus ( 12 ) acting as the internal power bus;
[0043] a DC/AC inverter ( 13 ) coupled to the output of the AC/DC converter ( 11 ) through the DC bus ( 12 ) for converting DC power to AC output;
[0044] a DC/DC converter ( 14 ) with the input directly connected to the DC power source, and the output to the DC bus ( 12 ) for boosting the DC to high voltage;
[0045] a charger ( 15 ) coupled to the AC input;
[0046] a DC power supply ( 16 ) for providing a continuous supply of electrical power to the local UPS module ( 10 );
[0047] a controller ( 17 ) built in with independent processing capability and the ability to accept the role of a virtual control center (VCC) through an arbitration over the high speed communication line (HSCL), and the controller ( 17 ) is connected by the DC/AC inverter ( 13 ), AC/DC converter ( 11 ), and DC/DC converter ( 14 ) for controlling the operation of the local UPS module ( 10 ); and
[0048] a bypass circuit ( 18 ) formed by a first-level relay ( 181 ) and a second-level relay ( 182 ), connecting across the input and output of each UPS module ( 10 ).
[0049] In the two-stage relay circuit, the first-level relay ( 181 ) circuit is implemented by a two-position relay, and the second-level relay ( 182 ) by a single-position relay. The second-level relay ( 182 ) is used for making or breaking the connection between the power output from the UPS module and the AC output bus. If the second-level relay ( 182 ) is closed, the power output of the UPS module ( 10 ) can be delivered to the parallel AC Output Bus. The first-level relay ( 181 ) is used for mode switching. When the UPS module is switched to the bypass mode, the first-level relay ( 181 ) will be toggled to the normal-open position, allowing the power from the main-line to be delivered to the parallel AC Output Bus through the closed second-level relay ( 182 ). When the UPS module is switched to the inverter mode, the first-level relay ( 181 ) will be toggled to normal-close position, and then the output of the DC/AC inverter ( 13 ) will be connected to the parallel AC Output Bus through the closed second-level relay ( 182 ). A STS switch is also connected across the first-level relay ( 181 ) for protecting the load from power interruption during the mode switching process.
[0050] The use of the two-stage relays ( 181 ) ( 182 ) enables the introduction of intelligent management on the modular power supply system. For example, a number of UPS modules ( 10 ) ( 101 ˜ 10 n ) are connected in parallel, and one of the modules is at fault. It is not necessary to switch all the UPS modules ( 10 ) ( 101 ˜ 10 n ) to the bypass mode, but only the failing UPS module needs to be isolated by tripping the second-level relay ( 182 ). This allows the other UPS modules ( 10 ) ( 101 ˜ 10 n ) to run in parallel unaffected by the action taken by the VCC to disconnect the failing UPS. If the UPS module ( 10 ) only has the first-level relay ( 181 ) without the second-level relay ( 182 ), and the first-level relay ( 181 ) is switched to the normal-open position, then the UPS module directly enters the bypass mode with two possibilities. In the first case, the system might cause other inverters to be paralleled to the main-line voltage; or in the second case, that some of the other UPS modules might be erroneously set to charge a bypassed UPS module while other UPS modules are disconnected from the main-line. Both cases would be undesirable from the system point of view.
[0051] Since the controllers ( 17 ) of all UPS modules ( 10 ) ( 101 ˜ 10 n ) are connected in parallel to the high speed communication line (HSCL) and the sync-clock-line (SCL), the controller ( 17 ) in each module ( 10 ) ( 101 ˜ 10 n ) is able to communicate with the counterparts in other parallel UPS modules ( 10 ) ( 101 ˜ 10 n ) through the HSCL, and each controller ( 17 ) has the independent processing capability and the ability to accept the role of the virtual control center (VCC) by participating in an arbitration over the HSCL. In the intelligent management model, the virtual control center (VCC) created in one of the parallel UPS modules ( 10 ) acts as the hub in controlling the operation of the modular power supply system. At any given time only one UPS module among all parallel UPS modules ( 10 ) ( 101 ˜ 10 n ) takes possession of the VCC, that means there is only one VCC in the whole network of UPS modules connected in whole system. If, for some reason, the original UPS module in possession of the VCC disappears from the UPS network, then another UPS module ( 10 ) ( 101 ˜ 10 n ) will be elected to be VCC among the peers by the same arbitration process that was used to select the first UPS module for taking over the role of the VCC.
[0052] The VCC has full control over the sync-clock-line (SCL), and sends out square wave sync clocks over the SCL continuously, as shown in FIG. 4 . The sync clocks issued by the VCC will be in sync with the inverter output voltage (InvVolt) having the same phase angle and frequency as the sync clock. Furthermore, the zero crossing of the inverter output voltage (InvVolt) of the UPS module is controlled by the controller ( 17 ) to follow the rising edge and falling edge of the sync clocks. In the present embodiment, the falling edge is also selected for triggering the system interrupt without extra sync-line as in the prior art.
[0053] The VCC has full control over the SCL by sending out square wave sync clocks, as shown in FIG. 4 . The output voltage from each inverter (InvVolt) should correspond with the phase angle and frequency of the sync clocks when the switch command is issued by the VCC. Furthermore, the zero crossing points of the InvVolt should also correspond with the rising edge and falling edge of the sync clocks. All the UPS modules ( 10 ) ( 101 ˜ 10 n ) connected over the UPS network are able to detect the falling edge of the sync clock and use it to produce a falling edge interrupt. With due consideration of any signal delay, all UPS modules ( 10 ) ( 101 ˜ 10 n ) connected in parallel will be able to generate a falling edge interrupt at the same time, as all modules ( 10 ) ( 101 ˜ 10 n ) experience identical moments of zero crossing of the output voltage. It is therefore to effect the synchronized switching from the inverter output to the bypass output with a system interrupt at the falling edge of the sync clock. The other advantage of using the square wave sync clock is that noise interference, if any, can be easily filtered out by software and hardware to prevent false switching of the modules ( 10 ) ( 101 ˜ 10 n ).
[0054] In FIG. 8 , when an interrupt occurs at the falling edge of the sync clock, the system has to determine whether the interrupt is caused by noise ( 811 ). If the system determines that the interrupt is not caused by noise, then the system proceeds to the interrupt process ( 812 ).
[0055] According to the present invention, the VCC acts as the hub in the implementation of intelligent management over the modular power supply system. After taking control of the sync-clock-line (SCL) ( 311 ), as shown in FIG. 3 , the VCC continuously sends out sync clock over SCL ( 312 ), and then collects the operation data from all parallel UPS modules ( 313 ) through the HSCL, from which the VCC determines whether it is necessary for all UPS modules to switch to the bypass mode ( 314 ). The basic criteria for making the to-bypass switch are that the total power requirement of the load should be smaller than the total capacity of the UPS modules. If the criteria are met, it is not necessary to switch the whole system to the bypass mode; if not, then all modules need to be switched to the bypass mode at once.
[0056] When the VCC determines that it is necessary to switch the whole system to the bypass mode, it needs to select an appropriate timing to send the to-bypass command to all UPS modules for the switching ( 315 ). The condition for issuing the command is to assure that all UPS modules ( 10 ) ( 101 ˜ 10 n ) are operating in synchronization. To accomplish the synchronization, it is necessary to have all the UPS modules ( 10 ) ( 101 ˜ 10 n ) receive the VCC command before the falling edge of the sync clock, with due consideration for the propagation delay for the signal and the interrupt. In the present invention, as shown in FIG. 4 , the VCC command is always issued in a predetermined time t 1 , such that all UPS modules have the time t 2 to cover the propagation delay for the signal and the interrupt. After the VCC sends out the to-bypass command ordering the UPS module to switch to the bypass mode ( 319 ), all the UPS modules ( 10 ) ( 101 ˜ 10 n ) will wait for the falling edge of the sync clock for the interrupt ( 320 ). After the interrupt takes place, the UPS module sends a toggle signal to the output relay ( 18 ) to switch to the bypass ( 321 ).
[0057] From the point of the UPS modules, all the parallel UPS modules ( 10 ) ( 101 ˜ 10 n ) will be able to receive the switch command and subsequently synchronize their switching operations through the HSCL and SCL. When a non-VCC UPS module ( 10 ) receives the to-bypass command ( 512 ), the module ( 10 ) waits for the falling edge of the sync clock that will appear over the sync-clock-line ( 513 ). After the interrupt is effected, the UPS module ( 10 ) will send a toggle signal to the output relay for switching to the bypass ( 514 ). The above procedures describe the synchronized operation of all UPS modules ( 10 ) ( 101 ˜ 10 n ) for switching to the bypass mode.
[0058] Still referring to FIG. 3 , when the VCC determines that it is not necessary to switch all modules ( 10 ) ( 101 ˜ 10 n ) to the bypass mode ( 314 ), it proceeds to check whether one or more UPS ( 10 ) ( 101 ˜ 10 n ) needs to be disconnected ( 316 ). If the condition is met, the VCC sends out the shutdown command to shut down the selected UPS module ( 317 ). Then the selected UPS module will trip its second-level relay ( 182 ) and shutdown itself after received the shutdown command from VCC.
[0059] When the system decides to toggle the output relay for making the mode switch, it is necessary to follow the standard operating procedures in order to prevent power break to the load and protect the output relay. In the preferred embodiment, a STS switch is used for this purpose.
[0060] When the selected UPS module ( 10 ) toggles the first-level relay ( 181 ), as shown in FIG. 1 , the STS switch has to be closed at the same time, connecting the output directly with the main-line. After the first-level relay ( 181 ) is switched to the bypass output, then the STS switch is opened again, thus switching the power output path from the inverter to the bypass circuit. From FIG. 4 , when the first-level relay ( 181 ) is toggled at the zero crossing of the AC output, since the output voltage coincides with the falling edge of the sync clock having the same phase angle, thus avoiding damage to the output relay from electric arcing.
[0061] The above-mentioned operations are mainly used for switching UPS modules from the inverter mode to the bypass mode. Alternatively, the process can be reversed for switching the UPS modules from the bypass mode back to the inverter mode, to be explained by the following paragraphs in conjunction with FIGS. 6, 7 .
[0062] When the VCC decides to put all parallel UPS modules ( 10 ) ( 101 ˜ 10 n ) back to the inverter mode from the previous bypass mode, the VCC collects the operation data from all UPS modules ( 10 ) ( 101 ˜ 10 n ) connected in parallel ( 613 ), from which the VCC determines whether all parallel UPS modules ( 10 ) ( 101 ˜ 10 n ) need to be switched back to the inverter mode ( 614 ). The basic criteria for the switch-back decision are that the total power required for the loads connected in the bypass mode is less than the total rated power of all parallel UPS modules, and that the output voltage of the inverter is restored to the normal condition.
[0063] When the VCC decides to switch back all parallel UPS modules ( 10 ) ( 101 ˜ 10 n ) in the modular power supply system to the inverter mode, the VCC also needs to select an appropriate timing to send out the switch-back command over the HSCL ( 615 , 616 ). After all the UPS modules ( 10 ) ( 101 ˜ 10 n ) have received the switch-back command, all UPS modules ( 10 ) ( 101 ˜ 10 n ) wait for the falling edge of the sync clock ( 617 ) for initiating the system interrupt. After the UPS modules ( 10 ) ( 110 ˜ 10 n ) initiated the falling edge interrupt, the UPS modules ( 10 ) ( 101 ˜ 10 n ) send a toggle signal to the output relay ( 18 ) to return to the inverter mode ( 618 ). For the non-VCC modules ( 10 ) ( 101 ˜ 10 n ), the above procedures are simplified, as shown in FIG. 7 , such that the UPS modules ( 10 ) ( 101 ˜ 10 n ) receiving the switch-back command only have to wait for the falling edge of the sync clock for initiating the interrupt ( 712 , 713 ). After the interrupt occurs, the UPS modules ( 10 ) ( 101 ˜ 10 n ) send a toggle signal to the output relay ( 18 ) switch back to the inverter output ( 714 ).
[0064] The design of the modular power supply system in accordance with the present invention offers several advantages:
[0065] (1) The system does not need any additional hardware for implementing a fixed control unit, thus realizing cost saving for the system hardware and also improving the overall system reliability;
[0066] (2) Intelligent power management: the virtual control center first collects the operation data from all parallel UPS modules for determining whether to switch all parallel UPS modules to the bypass mode. For example, when one of the modules is down, and the system has unused power capacity, then it is only necessary to isolate the failing module so as not to affect other modules still supplying power to the load. For the conventional technique, the whole system has to be switched to the bypass mode all at one time. The modular power supply system in accordance with the present invention is thus more reliable and able to satisfy the power requirements of different loads with more flexibility;
[0067] (3) The output relay can be triggered by a lower order interrupt at the falling edge of the sync clock, knowing that there would be a discrepancy of a few microseconds for the inverter output when the relay is switched, and that the output would be able to allow for a few microseconds of parallel connection by the main-line and the inverter without damaging the system;
[0068] (4) The use of the embedded sync-clock-line in a parallel modular power supply system could avoid possible interference from other modules, thereby improving the reliability in synchronized switching;
[0069] (5) Use of lower order interrupt could prevent pausing of normal system operation and system resources which could otherwise be useful for monitoring the power supply status of other UPS modules; and
[0070] (6) Use of zero crossing for switching the output relay could protect the output relay from damage by electric arcing.
[0071] 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. | A modular AC power supply system with fault bypass and the method of switching output modes is provided. The system architecture allows a plurality of uninterruptible power supply (UPS) modules connected in parallel to share the loads and tripped for fail independently. A virtual control center is automatically installed in one of the UPS modules at system initialization, used for controlling all UPS modules connected over the UPS network. When a disorder is detected in any UPS module, the virtual control center first collects the operation data from other parallel UPS modules through a high speed communication line, and then decides to send a command to the failing module to trip and shutdown, or to send a command to all parallel UPS modules to switch to the bypass mode through a high speed communication line. The system also employs a low priority interrupt with the falling edge of sync clocks to enhance the overall system reliability and the usage of system resources. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a taper journal bearing for rolls for use in rolling mills.
2. Description of the Prior Art
A taper journal bearing of a roll of this kind provides a bearing surface with oil film between a bushing housed in a bearing box of a roll stand and a sleeve closely fitted on a taper journal of the roll. In this case, a key is provided between the sleeve and the taper journal of the roll to prevent a relative movement therebetween.
The bearings of this type have been extensively used, but they have often encountered a problem of variation in reduction force due to an eccentricity of a rotating axis of the roll, which has been considered to be unavoidable resulting from the inherent construction of the bearings by the use of oil films.
It will be understood that the expression "reduction force" used hereinbelow will mean a force acting upon rolls for rolling plates therebetween.
Instead of the plain bearings, cylindrical roller bearings have been used in rolling mills, which may mitigate the variations in reduction force due to the eccentricity of rotating axes of rolls. However, the durability of the roller bearings is inferior to that of the plain bearings when used at high speeds with high accuracy. This problem has not been solved. In addition, a change of the rolls with the roller bearings is very troublesome. Accordingly, the plain bearings with oil film are greatly advantageous for multi-Hi rolling mills such as hot or cold strip mills.
Under the circumstances, it has been expected to eliminate the variation in reduction force in the plain bearings with oil film and the control of the variation in reduction force acting upon roll bearing boxes has been under investigation. However, any satisfactory answer to this problem has not been obtained.
It has been found from data in work rolls of 2-Hi rolling mills and back-up rolls of 4-Hi rolling mills that the variation in the reduction force is caused every one rotation of the roll due to the eccentricity thereof and there are minus peaks in extremely steep curves of the reduction force. It is very difficult, if not impossible, to compensate these violent changes in reduction force by the present technique for controlling thickness of plates to be rolled.
In view of the fact that such violent changes in reduction force occur only in the rolling mills using the plain bearings with oil film, we have thoroughly investigated the construction of the bearing allowing the violently varying reduction force and found that it is caused by the keyway formed in the sleeve for the key for the purpose of preventing the relative movement of the taper journal and sleeve.
The keyway formed in the inside of the sleeve is somewhat deeper than the height of the key extending beyond the taper journal to form a clearance between the key and a bottom of the groove or keyway of the sleeve. The clearance is unavoidably provided in consideration of the thermal expansion of the key. Such a clearance between the key and the bottom of the groove permits an elastic deformation of the sleeve to abruptly reduce the reduction force at the moment when the keyway of the sleeve comes in registry with a plane where the sleeve is subjected to the reduction force. It has been found that an amplitude of variation in reduction force or a difference between maximum and minimum reduction forces may often reach as much as 18 tons while idling of the roll irrespective of reduction forces and rotating speeds.
This abrupt change in reduction force will adversely affect in conjunction with a high plasticity of the material to be rolled at this stage the accuracy of the thickness of plates to be rolled at relatively low rolling speed in stands on an entry side (particularly a first stand) of tandem rolling mills and in initial rolling operation of reversible mills. The unevenness in thickness of the rolled plates caused by the abrupt change in reduction force could not be completely eliminated by repeated rolling operations following thereafter.
SUMMARY OF THE INVENTION
In order to avoid the abrupt change in reduction force effectively, according to the invention in consideration of the above fact, the key for preventing the relative movement of the sleeve to the taper journal of the roll is removed from the taper journal, upon which the reduction force acts directly, to an area upon which the reduction force does not acts.
It is an object of the invention to provide an improved taper journal bearing for rolls for use in rolling mills, whch remarkably mitigates the variation in reduction force to avoid unevennesses in thickness of plates to be rolled.
Another object of the invention is to provide an improved taper journal bearing for rolls for use in rolling mills, which will be relatively simple and inexpensive to manufacture, easy to install, maintain, repair and replace, and rugged and durable in use.
The invention will be more fully understood by referring to the following detailed specification and claims taken in connection with the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a part of a taper journal bearing for a roll in a prior art;
FIG. 2 is a graphical representation of variation in reduction force acting upon the bearing as shown in FIG. 1;
FIG. 3 is a sectional view of a part of a taper journal bearing of a preferred embodiment according to the invention; and
FIG. 4 is a graphical representation of variation in reduction force acting upon the bearing according to the invention as shown in FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the attached drawings, in FIG. 1, there is shown one end of a roll 2 for a rolling mill having a taper journal 4. A bearing for the taper journal as shown is a taper plain bearing in the prior art wherein a bearing surface with oil film is provided between a bushing 6 housed in a bearing box 8 of a roll stand and a sleeve 10 closely fitted on the taper journal 4. In generally, the roll has two taper plain bearings, only one of which will be described in detail, since they are symmetrically the same.
A key 12 is inserted into a groove or keyway formed in the taper journal 4 and the sleeve 10 to prevent it from rotating relative to the journal 4 of the roll 2 because otherwise such a relative rotation will cause heat from a sliding friction therebetween such that the sleeve 10 seizes or jams on the taper journal.
In FIG. 1, the roll 2 comprises a straight neck 4 which is covered with a sleeve retainer 16. A thrust bearing 18 is held by a lock nut 20, a bearing box end plate 22 bolted to the bearing box 8 and a bearing cover 24 bolted to the end plate 22.
In a rolling mill having rolls supported on such bearing surfaces with oil film, it has often encountered variations in reduction force due to an eccentricity of rotating axes of the rolls which adversely affect the accuracy of thicknesses of materials or plates to be rolled. It has been considered that such a disadvantage is unavoidable owing to the inherent construction of the bearings which support the load through oil films.
We have thoroughly investigated the construction of the bearing allowing the violently varying reduction force and found that it is caused by the keyway formed in the sleeve 10 for the key 12 for the purpose of preventing the relative movement of the taper journal 4 and sleeve 10.
Referring to FIG. 1, the keyway formed in the inside of the sleeve 10 is somewhat deeper than the height of the key 12 extending beyond the taper journal 4 to form a clearance between the key 12 and a bottom of the groove or keyway of the sleeve 10, which clearance is unavoidably provided for the thermal expansion of the key 12. Because of the clearance between the key 12 and the bottom of the groove, the sleeve 10 is elastically deformed to reduce the reduction force abruptly at the moment when the keyway of the sleeve 10 comes in a plane where the sleeve is subjected to the reduction force. It has been found that an amplitude of variation in reduction force or difference between the maximum and minimum reduction forces may reach as much as 18 tons while idling of the roll irrespective of reduction forces and rotating speeds.
This abrupt change in reduction force will adversely affect in conjunction with a high plasticity of the material to be rolled at this stage the accuracy of the thickness of plates to be rolled at relatively low rolling speed in stands on an entry side (particularly a first stand) of tandem rolling mills and in initial rolling operation of reversible mills. The unevenness in thickness of the rolled plates caused by the abrupt change in reduction force could not be completely eliminated by repeated rolling operations following thereafter.
In order to avoid the abrupt change in reduction force effectively, according to the invention in consideration of the above fact, the key 12 for preventing the relative movement of the sleeve 10 to the taper journal 4 of the roll is omitted so as to remove the elastic deformation of the sleeve 10 in the area upon which the reduction force acts.
Referring now to FIG. 3, wherein like components have been designated by the same reference numerals as in FIG. 1 and modified or improved components have been shown by numerals with primes, there is shown a preferred embodiment of the bearing according to the invention applied to a taper journal 4' of a roll 2'. The roll 2' is provided at its straight neck 14' with a key 12' instead of the key 12 located at the taper journal shown in FIG. 1. A bearing surface with oil film is provided between a bushing 6 housed in a bearing box 8 for a roll stand and a sleeve 10' closely fitted on the taper journal 4' as in FIG. 1. A sleeve retainer 16' is fitted on the straight neck 14' and bolted to the sleeve 10'. A thrust roller bearing 18 is held by a lock nut 20, a bearing box end plate 22 bolted to the bearing box 8 and a bearing cover 24 bolted to the end plate 22. The key 12' arranged within a groove or keyway formed in the straight neck 14' and the sleeve retainer 16' thereby indirectly preventing it from rotating relative to the roll 2'.
In the embodiment illustrated in FIG. 3, the key 12' is arranged between the straight neck 14' and the sleeve retainer 16'. As an alternative, a key instead of the key 12' may be radially provided in a keyway formed in an end surface or a shoulder of the straight neck 14' and an inner end surface of the sleeve retainer 16'. Furthermore, a key may be provided in a keyway formed between the end of the sleeve retainer 16' and a part of a reduced diameter portion of the roll onto which an inner race of the thrust bearing 18 is fitted.
Moreover, if the sleeve 10' extends substantially beyond the bushing 6 in its axial direction (i.e. beyond the area onto which a reduction force exerts), the sleeve 10' may be directly secured to the taper journal 4' with the extending portion of the sleeve. A pin, cotter or other known anchoring means may of course be used instead of the key. The anchoring means may be single or plural in one bearing.
In an experiment of the reduction force, rolls having sleeves 10' fixed thereto as shown in FIG. 3 were used as back-up rolls of a first stand of 6-tandem cold rolling mill. We measured reduction forces exerted on the rolls while they were idling under a reduction force of approximately 250 tons at a circumferential speed 100 meters per minute. One result recorded on a graph is shown in FIG. 4. The curve in FIG. 4 illustrates the fact that the amplitude of variation in reduction force decreases remarkably to a range of the order of approximately 3 tons probably resulting from an eccentricity of a rotating axis of the roll due to inherently unavoidable tolerance in manufacturing of the roll. The curve does not include the minus peaks as in FIG. 2 which extend over as much as 18 tons. The eccentricity of the roll as shown in FIG. 3 is only one sixth of that of the roll as shown in FIG. 1.
Table 1 shows a comparison of the variation in thickness of plates rolled by the rolls according to the invention with that of the prior art. The variations were measured by the use of X-rays at output sides of first and sixth roll stands of the 6 tandem cold rolling mill when the plates of 2.3 millimeter thickness were rolled to 0.211 millimeters. As can be seen from the Table 1, the variation in thickness according to the invention is about one half of that in the prior art.
TABLE 1______________________________________Variation in thickness of rolled plates first stand At sixth stand(due to (due to eccentricityeccentricity) of first stand) Total*______________________________________Present none none 2 - 3 μinventionPrior art 24.2 μ 4.4 μ 5 - 6 μ______________________________________ *The total includes the eccentricity of the first stand, unevennesses of starting material and errors in measurement.
The present invention can completely eliminate the steep variations or extremely sharp minus peaks of the reduction force resulting from the keyway of the taper journal and permits only a slight variation in the reduction force which serves to improve the rolling accuracy and facilitate the correction or compensation in the control of plate thicknesses to be rolled according to the existing circumstances. In this manner, the present invention can substantially avoid the variation in thickness of plates to be rolled due to the eccentricity of rolls.
While we have described our invention in detail in its preferred embodiment, it will be obvious to those skilled in the art, after understanding our invention, that various changes and modifications may be made therein without departing from the spirit or scope thereof. | The invention relates to a taper journal bearing for rolls, used in rolling mills. The bearing includes a bushing installed in a roll bearing box, a sleeve closely fitted onto a taper journal of the roll, for supporting a load thereof, an oil film deposited between the bushing and the sleeve, and means for attaching the sleeve to the roll at an area other than that directly subjected to a rolling force. The invention eliminates the increased variation in the reduction force taking place at each rotation of the roll, due to a deformation of the sleeve. The latter is caused by a clearance at a keyway formed in the sleeve, for a key arranged between the sleeve and the taper journal. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. §119 from U.S. Provisional Application Ser. No. 60/551,275 (filed Mar. 8, 2004), the disclosure of which is incorporated by reference herein for all purposes as if fully set forth.
BACKGROUND OF THE INVENTION
[0002] This invention pertains to inkjet printing on fabric and to a pretreatment solution for the fabric that allows high quality printing thereon.
[0003] Digital printing methods such as inkjet printing are becoming increasingly important for the printing of textiles and offer a number of potential benefits over conventional printing methods such as screen printing. Digital printing eliminates the set up expense associated with screen preparation and can potentially enable cost-effective short run production. Inkjet printing furthermore allows visual effects such as tonal gradients and infinite pattern repeat sizes that cannot be practically achieved with a screen-printing process.
[0004] One area of textile printing ideally suited to digital printing is the flag and banner market where short runs are common. However, printing of flags and banners presents unique challenges. For example, ink is printed on one side, but must penetrate the fabric so that the image is equally visible on the back (unprinted) side as the front (printed/face) side. In addition, while the ink must travel through the fabric, it must not travel laterally causing blurring and bleeding. This seemingly contradictory set of conditions is not easily achieved.
[0005] U.S. Pat. No. 5,847,740 discloses an inkjet printing process on nylon cloth.
[0006] U.S. Pat. No. 6,656,228 discloses a textile pretreatment solution comprising a cationic substance, an acid generator, and an alkyl or hydroxyalkyl substituted starch. Also disclosed is a polyamide textile pretreated with the composition and inkjet printing on the pretreated textile.
[0007] US2002/0081421 discloses an aqueous coating formulation for enhancing the image of acid dye based inks on fabrics. The coating formulation includes a cationic polymer or copolymer, a fabric softener, urea, and ammonium salts of multifunctional weak acids.
[0008] The above-mentioned publications are incorporated by reference herein for all purposes as if fully set forth.
[0009] It is an object of this invention to enable high quality inkjet printing of flags and banners
SUMMARY OF THE INVENTION
[0010] The present invention pertains in one aspect to a pretreatment solution for fabric. The inventive pretreatment solution is an aqueous solution comprising a polycationic compound, a viscosity builder and an acid donor.
[0011] The present invention pertains, in another aspect, to a fabric that has been treated with the inventive pretreatment solution. The wet pick-up of pretreatment solution, although not specifically limited, is advantageously in the range of about 20 to about 100 grams of solution, per 100 grams of fabric. In one embodiment, the wet pick-up of pretreatment solution is in the range of about 25 to about 75 grams of solution, per 100 grams of fabric. The fabric is preferably a woven fabric comprising a synthetic polyamide fiber such as nylon 6 and nylon 6,6 fiber.
[0012] In yet another aspect, the present invention pertains to an inkjet printing method wherein the pretreated fabric is imaged with an inkjet printer. The printer can be, for example, the DuPont™ Artistri™ 2020 or 3210 printer, and associated inks. Especially preferred are acid dye inks.
[0013] These and other features and advantages of the present invention will be more readily understood by those of ordinary skill in the art from a reading of the following detailed description. It is to be appreciated that certain features of the invention which are, for clarity, described above and below in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any subcombination. In addition, references to in the singular may also include the plural (for example, “a” and “an” may refer to one, or one or more) unless the context specifically states otherwise.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0000] Pretreatment Solution
[0014] The inventive pretreatment solution comprises a polycationic compound, a viscosity builder, an acid donor and water. Optionally, other ingredients can be added. Ingredient percentages mentioned herein after are weight percent based on the total weight of the final solution, unless otherwise indicated.
[0015] The polycationic compound is an organic compound with a plurality of cationic (protonated or quarternized) amine groups. Suitable polycationic compounds preferably comprise on average at least five cationic amine groups per molecule, and more preferably on average 10 or more cationic amine groups per molecule, and includes, for example, cationic amine polymers. The cationic polymers can be low molecular weight, for example about 500 to about 1000 (Mn), or can be higher molecular weight, for example greater than about 10000 (Mn), or even greater than about 100000 (Mn). This will depend on a number of factors such as desired cationic content, solution viscosity and other desired properties recognizable by those of ordinary skill in the art.
[0016] The polycationic compound is generally present in an amount of at least about 0.2 wt % up to about 10 wt %, and more typically in the range of about 0.3 wt % to about 4 wt %, based on the total weight of pretreatment solution.
[0017] Examples of suitable cationic polymers include polyethyleneimines, polyallylamines and polyvinylpyridines. Cationic polymers are available commercially, for example, under the tradenames Polycup®, Perform™ and AquaCat™ from Hercules Incorporated (Wilmington, Del., USA); “Dye Techs” from American Textile, LLC (Duluth, Ga., USA); and, “Discofix” from Apollo Chemical Corporation (Burlington, N.C., USA).
[0018] The viscosity builder increases the viscosity of the medium in which it is dissolved or dispersed, and is typically a high molecular weigh natural or synthetic polymer that swells in water. Examples include starch and its derivatives; cellulose and modified cellulose; guar gum; locust bean gum; and bio-synthetic gums like xanthan, gum arabic, gum tragacanth, polyvinylpyrrolidone and polyvinylalcohol. Preferred viscosity builders are cellulose derivatives.
[0019] Preferably, the viscosity builder is not anionically charged at neutral pH. Viscosity builders comprised of a substantial number of carboxylic acid groups will be anionically charged at neutral pH and are preferably avoided. The viscosity builder is generally present in the range of about 0.5 wt % to about 10 wt %, and more typically in the range of about 1 wt % to about 4 wt % weight percent, based on the total weight of pretreatment solution.
[0020] An acid donor is a compound that lowers the pH of the environment upon activation by heat. Such species are typically salts of organic or inorganic acids, preferably an ammonium, alkyl ammonium or quarternary ammonium salt. Most preferably the acid donor is ammonium salt such as ammonium sulfate. Other examples include ammonium citrate, ammonium acetate and the like. The acid doner is generally present in solution at about 0.5 wt % to about 20 wt %, and more typically about 1 wt % to about 10 wt %, based on the total weight of pretreatment solution.
[0021] Other optional ingredients may include, but are not limited to, humectants and biocides. A humectant is an ingredient that can retain water and includes liquids such as (poly)glycols and (ethoxylated)glycerol, and solids such as urea. Biocides prevent microbial degradation—their selection and use is generally well known in the art. In a preferred embodiment, the pretreatment solution comprises urea, preferably in an amount ranging from about 0.5 wt % to about 5 wt % based on the total weight of the pretreatment solution.
[0022] The balance of the pretreatment solution is water.
[0023] The ingredient levels must be sufficient to provide adequate coating weight after drying, but not so high that the solution becomes too viscous and fails to coat and penetrate the fabric evenly. The viscosity at 25° C. is preferably greater than about 100 cP and less than about 2000 cP, more preferably between about 200 and about 1000 cP, and especially between about 250 and about 500 Cp. The pH of the pretreatment solution is preferably between about 6 and about 8, and preferably about neutral.
[0000] Fabric Pretreatment
[0024] The fabric to be pretreated is preferably a woven fabric comprising synthetic polyamide fibers. Most commonly, the synthetic polyamide fibers are nylon-6 and/or nylon-6,6 fibers. For flag and banner stock, the fabric is generally about 70 to about 200 deniers. A commercial example of such stock Solarmax® from Glen Raven Mills.
[0025] Application of the pretreatment to the fabric can be any convenient method and such methods are generally well-known in the art. One example is an application method referred to as padding. In padding, a fabric is dipped in the pretreatment solution, then the saturated fabric is passed through nip rollers that squeeze out the excess solution. The amount of solution retained in the fabric can be regulated by the nip pressure applied by the rollers. Other pretreatment techniques include spray application wherein the solution is applied by spraying on the face or face and back of the fabric. The wet pick-up of pretreatment solution is preferably between about 20 and about 100 grams of solution, and more preferably between about 25 to about 75 grams of solution, per 100 grams of fabric.
[0026] After application of pretreatment the fabric is dried in any convenient manner. The final percent moisture is (approximately) equal to the equilibrium moisture of the pretreated fabric at ambient temperature, and can vary somewhat depending on the relative humidity of the surrounding air.
[0027] The resins remaining in the fabric after drying provide the absorbent layer for the inkjet inks during printing. It will be appreciated that sufficient resin must be present to absorb the ink load applied. On the other hand, the presence of too much resin may prevent proper penetration. Routine optimization will reveal appropriate coating levels for a given printer and ink set.
[0000] Printing Method
[0028] Printing can be accomplished by any inkjet printer equipped for handling and printing fabric. Commercial printers include, for example, the Dupont™ Artistri™ 3210 and 2020 printers, and the Mimaki TX series of printers.
[0029] A variety of commercial ink sets are available for use with these printers. Especially useful for printing on nylon are acid dye inks.
[0030] The amount of ink laid down on the fabric can vary by printer model, by print mode (resolution) within a given printer and by the percent coverage need to achieve a given color. The combined effect of all these considerations is grams of ink per unit area of fabric for each color. In one embodiment, ink coverage is adpreferably between about 5 to about 17 grams of ink per square meter of fabric. Again, there is a balance between the ink density needed to achieve a desired color and the absorption capacity of the coating resins in the pretreatment.
[0000] Post Treatment of Fabric
[0031] Printed fabric will typically be post-treated according to procedures well-known in the textile art.
EXAMPLES
[0000] Pretreatment Solutions
[0032] Pretreatment solutions were prepared according to the recipes in the following table. The identity of commercial components is as follows:
Natrosol®=Hydroxy ethyl cellulose (Hercules Corporation) Polucup® 172 =Cationic polymer (Hercules Corporation) Perform® 1279 =Cationic polymer (Hercules Corporation)
[0036] Proxel GXL=Biocide (Avecia)
Pretreatment Solution composition, as % weight Ingredient Control Inventive Solution Polycationic Compound 0 As indicated Natrosol ® 2 2 Ammonium sulfate 5 5 Urea 2 2 Proxel GXL 0.2 0.2 Water (balance to 100%) Bal Bal
[0037] In the above formulation, inventive solutions contained polycationic compound as follows:
Solution 1a=1% Perform® 1279 Solution 1b=2% Perform® 1279 Solution 1c=3% Perform® 1279 Solution 1d=5% Perform® 1279 Solution 2a=1% Polycup® 172 Solution 2b=2% Polycup® 172 Solution 2c=3% Polycup® 172 Solution 2d=5% Polycup® 172.
Fabric Pretreatment
[0046] Fabric (Solarmax®), 200 denier nylon, was treated with each solution by standard padding procedures. The wet pick-up was 40 grams per 100 g of fabric. The treated fabric was dried by allowing it to stand for at least 8 hours at ambient room temperature (about 25° C.) at which point it had reached equilibrium moisture.
[0000] Printing Conditions
[0047] Dried, pretreated fabric was printed with a DuPont™ Artistri™ 2020 printer at 360×600 dpi with DuPont™ Artistri™ A774, A746, A795, A768, R715, R735, A743 and A776 inks.
[0048] Various flags and banners were printed to give 50%-200% ink coverage. At the 360×600 dpi setting, 50% coverage was about 5.8 grams of ink per square meter of fabric, and 200% coverage was about 23.4 grams of ink per square meter of fabric.
[0000] Post Treatment
[0049] Printed samples were post-treated in saturated steam at 102° C. for 30 minutes then washed twice, first in cold water for 5 minutes, then in warm water (60° C.) for 10 minutes.
[0000] Evaluation
[0050] Color penetration to the back side of the fabric was evaluated according to the following formula:
Degree of penetration = K S face - K S back K S face × 100 %
K/S is a Kubelka-Munk function that gives a measure of reflectance of an opaque layer at a given wavelength. Measurements were made with an X-rite spectrophotometer, model SP64. K/S is calculated from the reflectance as follows, K/S=(1−R) 2 /2R where R is the minimum reflectance in fraction.
[0051] The absolute value of degree of penetration (difference in depth of color between face and back of fabric as calculated by the equation above) should be no more than 20%, and preferably as close to zero as possible. In other words, the printed fabric should have about the same color density on both sides of the fabric.
[0052] Bleed is the lateral migration of ink away from the intended location on the fabric. It is evident as “blurred” or “feathered” lines or edges rather than sharp, straight edges and also as the unintended running together of adjacent colors. The evaluation of bleed, both color-to-color (for two adjacent colors) and color-to-white, was made visually according to the following scale:
Very Good=little or no bleed evident (commercially acceptable) Good=slight amount of blurring, feathering or running of colors (marginally acceptable commercially) Poor=severe blurring, feathering or running of colors (unacceptable)
[0056] Results
Degree of Penetration (%) - Pretreatment Solutions 1a-1d 1a 1b 1c 1d Color American Flag Blue −9.08 −7.32 −9.32 0.81 American Flag Red −5.13 8.73 1.09 9.22 Union Jack Blue −3.28 −4.16 0 17.7 Canadian Flag Red 0.54 10.6 3.94 13.2 Italian Flag Green −1.08 3.53 6.64 6.0 Blue −1.79 16.6 13.6 16.2 Black 50.5 65.7 58.2 65.7 Evaluation Color/Color Bleed Very good Very good Very good Very good Color/White Bleed Very good Very good Very good Very good
[0057]
Degree of Penetration (%) -
Pretreatment Solutions 2a-2d, and Control
Color
2a
2b
2c
2d
Control
American Flag Blue
−20.7
15.6
15.4
11.4
1.02
American Flag Red
−4.1
7.6
2.65
10.9
7.42
Union Jack Blue
−7.92
3.24
3.67
10.8
4.25
Canadian Flag Red
0.86
14.9
10.1
10.7
2.94
Italian Flag Green
1.83
1.7
−1.1
−0.96
0
Blue
1.93
20.4
29.2
13.7
16.2
Black
48.7
47.7
46.1
47.7
37.5
Evaluation
Color/Color Bleed
Good
Good
Good
Good
Poor
Color/White Bleed
Very good
Very good
Very
Very
Poor
good
good
[0058] As can be seen from the results, use of polycationic compounds reduced color/color and color/white bleed significantly compared to the control without cationic polymer, yet generally allowed good penetration for even color on both sides of the fabric. Although both the cationic agents were effective, the Perform® 1279 was somewhat better overall than the lower molecular weight Polycup® 172 because of the superior color/color bleed results.
[0059] The poor degree of penetration results particular to the black color (> than 20%) indicate the printer settings or ink formulation for that color needs to be adjusted. | This invention pertains to inkjet printing on fabric and to a pretreatment solution for the fabric that allows high quality printing thereon. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to burner units to simulate burning in a traditional fireplace and more particularly to units which may be operated in a non-vented dwelling space.
2. Prior Art
Since at least colonial times the fireplace has been a source of heat during cold weather and for cooking. Typically, wood or coal is burned with the products of combustion vented outside by a chimney.
The Franklin stove, invented by Benjamin Franklin in the late 1700's, provided a vastly improved heat source because a greater percentage of the generated heat transferred to the space in which the stove was located while a lesser percentage vented to the outside.
While in most modern dwellings the fireplace is no longer the primary source of heat, an open flame in a living space remains a pleasurable experience for its aesthetic and physiological effects. As such, a number of substitute structures have been suggested to improve heat transfer and eliminate the need for the traditional masonry chimney. U.S. Pat. Nos. 1,867,740, 3,636,307 and 3,742,189 set forth electrical energized heating units with open burning simulation created by a flow of air and light directed through defusing materials.
A structure which provides improved heat transfer is set forth in U.S. Pat. No. 2,134,935 where self-contained ducting is used to transfer heat to room air circulating in the ducting. In U.S. Pat. No. 3,533,394 the products of combustion from a gas log in a fire box are discharged externally by an exhaust fan. This fan also circulates room air in duct work about the fire box. U.S. Pat. No. 3,654,913 discloses a gas fueled fireplace with artificial logs. Heat is generated in a sealed chamber having an inlet and outlet connected to the outside while room air is circulated about the sealed chamber.
In addition to wood, coal, natural gas and electricity as heat sources, other hydrocarbon based materials also have long been in use. U.S. Pat. Nos. 500,765, 889,049 and 960,064 each suggest the use of alcohol as a fuel to burn and produce heat. In the '765 and '049 reference alcohol is burned in a cooking stove while the '064 reference sets forth an alcohol burning pocket heater.
SUMMARY OF THE INVENTION
A burner unit of this invention has a fuel cell carried on a grate which in turn is connected to a base plate. The fuel cell includes a container portion having sidewalls with guides which extend inward beyond a rear wall of the container portion. A lid having slides operatively engaging the container guides may be positioned to open or close the container portion where fuel containing canisters are held. Artificial logs may be placed on the grate and fuel cell lid.
The base plate is formed with a cutout to hold a piece of tinted glass, for example. The glass allows light from a fixture attached to the base plate to shine upward and reflect from rock pieces on the glass. The burner unit may be formed as part of an enclosure. The enclosure in turn may be placed in a wall opening, piece of furniture or the enclosure may be freestanding.
To use the burner unit the fuel cell lid is positioned to allow ignition of fuel in the canisters. The fuel burns with a slight flame to form heat and smokeless, nontoxic products of combustion which need not be vented from the space in which the unit is located. Vents in the fuel cell allow air to circulate about the canisters to regulate surface tempeatures of the canisters and fuel cell and prevent the fuel from overheating. Light reflecting from the rock pieces produces a glowing ember effect from under the grate.
The burner unit of this invention provides several advantages over other such units presently known or in use.
First, the burner unit produces the sensorial effects of a traditional fireplace. Those about the unit are warmed by the generated heat while at the time enjoy the appearance of an open flame and glowing coals therebeneath. The fuel can be scented to produce a wood burning odor if desired. Thus, one may enjoy the physiological effects of open burning in a fireplace without having one.
Secondly, the unit may be used by those living in a multi-family dwelling unit, such as an apartment, where it is most uncommon to find a traditional fireplace. Additionally, the unit is quite portable and thus may be moved to and used in other subsequent locations of a similar nature.
Lastly, the unit is safe to operate without a need for undue precautions. The fuel canisters may be readily removed and replaced since air circulating about the fuel cell prevents the canisters or fuel cell from becoming overly hot.
Additionally, the burning fuel may be extinguished by simply sliding the fuel cell lid forward to cover the container portion and deprive the fuel of sufficient oxygen to continue to burn. Any residual fumes in the cell are vented through lid openings. If the unit were to be tipped forward inadvertently, the lid self-closes. Of most importance to a consumer is that the unit as combined with the noted enclosure is Code approved.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a burner unit of this invention installed in a freestanding enclosure.
FIG. 2 is a perspective view of the burner unit and enclosure forming part of a decorative furniture piece.
FIG. 3 is a plan view partially in section of the enclosure with all but a portion of a base plate of the burner unit removed.
FIG. 4 is a front elevation view of the enclosure of FIG. 3.
FIG. 5 is a side elevation view of the enclosure.
FIG. 6 is a section view as seen generally along the line 6--6 of FIG. 3.
FIG. 7 is detailed plan view partially in section of the burner unit.
FIG. 8 is a front elevation view of the burner unit.
FIG. 9 is a side elevation view of the burner unit.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A burner unit of this invention is shown generally in FIGS. 1 and 2 and designated 10. As shown, the unit 10 is positioned in an enclosure 12. The unit 10 and enclosure 12 may be formed as one assembly, and as shown is freestanding. In FIG. 2 the unit and enclosure 10 and 12 are installed in a furniture piece, for example a chest 16 having a hinged lid 18 providing access to an interior storage space. Alternatively, the unit and enclosure 10 and 12 may be installed in a wall opening in a dwelling space. It should be understood that the unit 10 also may simply be placed on a standard hearth of a traditional fireplace. In this latter case no enclosure 12 would be required.
The burner unit 10 includes a base plate 20 to which is attached a front and rear support frame 22, 24. Each frame 22, 24 has a pair of legs 25 which connects with a cross member 26. The legs 25 are positioned next to side edges 28 of the plate 20 with the rear support frame 24 aligned with a rear edge 30 of the plate 20. The support frames 22, 24 carry a grate 32 defined by a set of equispaced bars 34. Each grate bar 34 has a horizontal extension 36 which connects with a front upright segment 38 that act as stops. The segments 38 are positioned at a slight angle from the vertical.
A fuel cell 40 is affixed to the grate horizontal extensions 36 and includes a lower container portion 42. The container portion 42 is formed by a bottom wall 44, spaced apart sidewalls 46 and a front and a rear wall 48, 50 which join to define an interior space 52. In the container portion rear wall 50 is a set of vertical slots 54, see FIG. 1. Attached to the sidewalls 46 along an upper edge 56 of each is an angle shaped guide 58. These guides 58 extend rearward beyond the rear wall 50. An inner end 60 of each guide 58 aligns with the base plate rear edge 30.
Assembled to the container portion guides 58 is a pair of channel shaped slides 62 attached to sides 64 of a lid 66. The lid 66 further includes a top wall 68 formed with a folded, upturned front edge 70. Attached to the lid top wall 68 is a back wall 72. Forward movement of the lid 66 is limited by engagement of the lid back wall 72 with the container portion rear wall 50. Attached to the lid top wall 68 is a pair of upward extending spaced apart mounting posts 74 which are located in front of vent openings 76 in the top wall 68, see FIG. 7.
As seen in FIG. 1, the burner unit 10 further includes a set of log pieces. An upper log piece 80 is formed with inner openings 82 to receive the lid posts 74 and secure the upper log 80 to the fuel cell lid 66. Two lower log pieces 84 are positioned on the grate extensions 36 between the fuel cell front wall 48 and the grate bar upright segments 38. The log pieces 80, 84 may be made of a non-combustible material, for example a ceramic.
The burner unit 10 may be made as an integral part of the enclosure 12. As so combined, the fuel cell guides 58 may be attached to an enclosure inner back wall 96. As shown in detail in FIGS. 3-5, the enclosure 12 is made having a double wall construction comprising outer sidewalls 90 which taper rearward to join an outer back wall 92. Inner sidewalls 94 are spaced from the outer sidewalls 90 and connect with the inner back wall 96 which is spaced in a like manner from the outer back wall 92. Likewise, an outer and inner top wall 98, 100 are spaced apart and connect with the sidewalls 90, 94 and back walls 92, 96. Spaces 102 formed between the various inner and outer walls may be filled with dead air or filled with an insulating material to insure that the outer walls 90, 98 remain at a safe temperature during unit use.
The sidewalls 90, 94 and the top walls 98, 100 each have a front flange which connect respectively to form side mullions 104 and a top mullion 106. Attached between the inner sidewalls 94 and to the inner top wall 100 next to the top mullion 106 is a deflector hood 110. The hood 110 is lined with an insulation piece 111. Immediately below the hood 110 is a rod 112 which extends between the inner sidewalls 94 and attached to such. The rod 112 provides support for a foldable screen 114 which may be used to selectively cover a face opening 116 of the enclosure 12.
The enclosure 12 further includes a bottom plate 120 with a front flange 122 similar in appearance to the top mullion 106 so that the face opening 116 is framed by the side mullions 104, top mullion 106 and bottom plate flange 122, see FIG. 4. The bottom plates 120 has a front cutout 130 defined by a narrow center portion 132 joined by enlarged end portions 134. Positioned immediately to the rear of the front cutout center portion 132 is a rear cutout 136. The rear cutout 136 has side edges 138 located adjacent inner sides 140 of the front cutout enlarged end portions 134. A front edge 142 of the rear cutout 136 in turn is located adjacent to a rear side 144 of the front cutout center portion 132. A connecting strip 146 having an upright flange 148 separates the front cutout center portion 132 from the front edge 142 of the rear cutout 136.
As seen in FIGS. 1, 4 and 5, the enclosure 12 is positioned on a base 152. The base 152 has sufficient height for installation of a fluorescent light fixture 154 of standard construction and circuitry for a fluorescent lamp 156. The fixture 154 may connect directly with a 110 volt source of electricity by a cord 158. Alternately, the fixture 154 may include a junction box (not shown) for direct wiring to a circuit, for example in a wall opening. Note that the fixture 154 is positioned to align with the enclosure bottom plate front cutout 130. The fixture 154 is operated by a switch 160 mounted in the enclosure bottom plate 120.
A toggle lever 162 of the switch 160 projects upward through an opening 164 in the burner unit base plate 20 with the burner unit 10 positioned on the enclosure bottom plate 120. As best understood by viewing FIGS. 3 and 6, the burner unit base plate 20 also is formed with a cutout 166 substantially the same size as the enclosure rear cutout 136 and positioned to align with such with the unit 10 in the enclosure 12. About the burner unit base plate cutout 166 are raised, angle shaped lip portions. Side lip portions 168 and a rear lip portion 170 have a straight top edge 172 while a front lip portion 174 is formed with a series of scallops 176.
Positioned between the enclosure bottom plate 120 and the raised lip portions 168, 170 and 174 of the burner unit base plate cutout 166 is a transparent member 180. This member 180 may be a piece of glass or plastic, for example. Edges 182 of the member 180 are encased in a channel shaped gasket 184 so as to suspend the member 180 between the bottom plate 120 and burner unit base plate cutout raised lip portions 168, 170 and 174. Note that the gasket 184 on a front edge 185 of member 180 abuts the connecting segment flange 148, see FIG. 6. This flange 148 aids locating the transparent member 180 while the burner unit base plate 20 to being positioned to align the cutouts 136, 166. Note further than when the burner unit 10 is not used in the enclosure 12, the base 152 has a top wall similar to the enclosure bottom plate 120 to hold the transparent member 180 as described above.
To prepare the burner unit 10 for use, the fluorescent lamp 156 is installed in the base light fixture 154; then the light fixture 154 connected to a power source. When the unit 10 is to be placed on the bottom plate 120 for use in the enclosure 12, the front cutout 130 provides access to the fixture 154. The enlarged end portions 134 allow for manual rotation of the lamp 156 to secure the lamp 156 in the fixture sockets. In the explanation of burner operation, it is assumed that the burner unit 10 is installed in the enclosure 12.
Next, several rock pieces 190 are placed on a top surface 192 of the member 180. The preferred rock material is lava. The switch lever 162 is placed at "ON" to illuminate the rock pieces 190 producing a visual effect of burning coals. Since a reddish glow is needed, the member 180 is tinted or the lamp 156 color coated accordingly. The scallops 176 on the cutout front lip portion 174 aid in creating an authentic glowing ember appearance because the scallops 176 make an irregular demarcation line between the lighted member 180 and the non-lighted burner unit base plate 20.
Canisters 194 containing a fuel 196 then may be placed in the fuel cell container potion 42 by sliding the lid 66 and attached upper log piece 80 to the rear. The canisters 194 may be a standard one-pint size so that the container portion 42 holds three such canisters 194. The preferred fuel is a gelled alcohol identified in copending patent application Ser. No. 619,041 filed June 11, 1984. This fuel burns with a slight flame and without forming toxic products of combustion or smoke. Additionally, the fuel 196 may be scented to burn with a wood odor, for example.
The fuel 196 may be ignited with a safety match or pocket lighter. Burning of the fuel 196 is regulated in part by the slots 54 in the fuel cell container portion rear wall 50 which allows air to flow to the flame and about the canisters 194. This air flow helps to cool the canisters 194 and fuel 196 to maintain burning at a rate sufficiently low to prevent overheating of the fuel cell 40 and enclosure 12, for example. Heat from the burning fuel 196 passes through the screen 114, which should have been pulled closed for safety reasons, and is directed by the hood 110 into the space in which the unit and enclosure 10, 12 are located.
When use of the burner unit 10 is no longer desired, the screen 114 may be pulled to one side of the enclosure face opening 126 to provide access to the fuel cell 40. The lid 66 and attached upper log piece 80 then may be slid forward to enclose the canisters 194. Because the air flow to the fuel 196 is no longer sufficient to sustain combustion, and the flame is extinguished. Note that if the unit and enclosure 10, 12 were inadvertently tipped forward as the fuel 196 is burning, the lid and log 66, 80 would slide forward under the influence of gravity to enclose the canisters 194 and likewise extinguish the flame. Any vapor from the now extinguished fuel 196 produced by residual heat in the canisters 194 and fuel cell 40 vents through the lid openings 76 to prevent a build-up of vapor in the now closed fuel cell 40. Last, the light fixture 154 is deenergized by moving the switch lever 162 to the "OFF" position.
While an embodiment of this invention has been shown and described, it should be understood that this invention is not limited hereto except by the scope of the claims. Various modifications and changes can be made without departing from the scope and spirit of the invention as the same will be understood by those skilled in the art. | A burner unit particularly adapted for use in a non-vented dwelling space as a fireplace substitute includes a fuel cell carried on a grate which in turn is connected by support frames to a base plate. The fuel cell has a slidable lid to provide access to a fuel canister holding container portion of the fuel cell. The base plate has a glass covered cutout to allow upward illumination from a light fixture connecting with the unit below the base plate. The burner unit may be installed in an enclosure which in turn may be freestanding, placed in a wall opening or in a furniture piece. To use the unit, fuel in the canisters is ignited to burn with a slight flame and produce heat and toxic-free products of combustion. The light fixture is energized to illuminate rock pieces on the glass and simulate glowing embers under the grate. With artificial log pieces positioned on the grate and fuel cell, the unit provides sensorial effects similar to those of a wood burning fireplace for enjoyment by those in the dwelling space. | 5 |
BACKGROUND
[0001] This disclosure relates to systems and processes for extracting liquids and solids from mixtures that contain liquids and solids such as, but not limited to, manure, food processing waste by-products and other substances that require the extraction and separation of liquids from solids. More specifically, the systems and processes include separately extracting liquids via spaced plates as concentrated liquids from such things as animal manure and food processing waste.
[0002] Concentrated liquid nutrients are heated by various means resulting in concentrated Fertilizer. Solid organic materials are separated, dried and may be disposed of as fuel, used as animal bedding or spread on agricultural fields.
[0003] Animal feeding operations (AFO) are constrained by animal manure, animal urine and water contaminated by animal manure, urine and other nutrients if water comes into contact with waste. AFOs must continually dispose of manure and wastewater, which is a difficult, costly and dangerous process due to the presence of methane gas. Wastewater disposition is especially difficult since wastewater nutrients generally exceed State and Federal clean water standards. Wastewater evaporation is too slow of a process for AFOs.
[0004] Food processing operations are also constrained by wastewater used in processing activities. Food processors must continually dispose of organic waste and wastewater, Similar to AFOs, wastewater and organic material disposition is difficult for food processors since the wastewater nutrients exceed State and Federal clean water standards. And similar to AFO's, wastewater evaporation is too slow of a process for food processors.
[0005] Sand and other granular particles can cause problems with manure and certain food by-products. Sand and similar particles can be very corrosive and wear away metal in screw augers or sand separation equipment, including metal components for such equipment.
DEFINITIONS
[0006] In this disclosure, an AFO is defined as an animal feeding operation which stables, confines or concentrates animals. AFOs affected by manure and wastewater disposition issues are primarily, but not limited to, the following agricultural activities: dairy farms, swine farms, veal/beef cattle feeding operations, turkey farms, chicken (broiler) farms, chicken (laying) farms, sheep or lamb farms, and horse farms.
[0007] In addition to the aforementioned, any process, where animal manure, urine and/or wastewater are a by-product, is included in this disclosure.
[0008] Manure is defined as animal excrement generated by the animal's intestinal system and includes bedding, compost and raw materials or other materials commingled with animal excrement or set aside for disposal. Urine is defined as liquid animal excrement generated by the animal's kidney system. Wastewater is defined as water contaminated by contact with manure, urine and other nutrients, such as during the AFO process.
[0009] In this disclosure, a food processor is defined as any operation that transforms whole fruits and vegetables into edible concentrations, such as converting whole apples into applesauce. Food processing waste and wastewater disposition issues are found in a substantial number of food processing activities throughout the country.
SUMMARY
[0010] The present disclosure provides a press process and system used to separate mixtures of solid and liquid materials, such as manure, into dried solids and concentrated wastewater. Waste water can be heated by various means resulting in concentrated fertilizer. Solid organic materials can be separated, dried and may be disposed of as fuel, used as animal bedding or spread on agricultural fields.
[0011] The disclosure includes flowing a substance, such as manure, into a cylinder which is comprised of a rigid portion and an end or continuing segment that is comprised of a series of plates. Depending on the viscosity of the material, the plates are separated by spacers between the plates. A piston is used to apply pressure to the material in the cylinder. The pressure from the piston squeezes the substance in the cylinder causing the liquid component to flow out of the cylinder through the plates while solid materials remain in the cylinder. A pressure cone at the distal end of the plate section maintains pressure on the solid waste in the cylinder, yet allows the solid materials to escape from the cylinder as additional waste is added to the cylinder and squeezed by the piston.
[0012] Liquids that are extracted from the plate press preferably flow to a liquid collecting area for further processing.
[0013] Solids that are extracted from the plate press preferably flow to a covered conveyor system where additional heated forced air drying takes place. The solid materials in the conveyor system can be heated to temperatures that will kill bacteria that may be present in the solid material. Upon exiting the conveyor system, the solid material is either held in a collecting area for further processing or may be used as fuel to provide heat to the conveyor drying system.
[0014] Sand can be extracted with solids where the combined organics come out the end of the system adjacent to the pressure cone. The sand has less corrosive effect where a vibrator screen can be used to knock sand off to pass through a screen to a collection area.
[0015] The plate press system for extracting and separating liquids and solids preferably includes several plate press assemblies aligned on a single crankshaft. The system includes a cylinder for accepting waste and a piston for providing pressure and pushing waste in the cylinder. A plunger of the piston preferably reciprocates within the cylinder to push waste through the cylinder into spaced plates with apertures aligned with the cylinder. Pressure from the piston on waste in the apertures forces liquids to pass between the spaced plates as extracted from the system. An exit port is aligned with the apertures with a counterweighted pressure cone operably connected to the exit port. Pressure from the piston on waste in the cylinder and thus in the apertures can overcome force of the pressure cone to allow solids to egress out the exit port past the pressure cone. A tip of the pressure cone preferably passes through the exit port when connected and rests in some of the apertures of the plates to provide a shape that allows solid waste to pass out the exit port when pressure on the pressure cone is overcome by pressure on the waste from the piston.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The above mentioned and other features of this disclosure and the manner of obtaining them will become more apparent, and the disclosure itself will be best understood by reference to the following description of systems and processes taken in conjunction with the accompanying figures, which are given as non-limiting examples only, in Which:
[0017] FIG. 1 is a perspective view of a four cylinder plate press system with a conveyor system;
[0018] FIG. 2 is a closer perspective view of a four cylinder plate press system focusing on the plate press portion;
[0019] FIG. 3 shows a plate press assembly;
[0020] FIG. 4 is a schematic of the plate press assembly with a pressure cone; and
[0021] FIG. 5 is an exploded drawing of the plate press assembly components including the pressure piston, the plate press cylinder, liquid extraction plates, and the exit port
[0022] The exemplifications set out herein illustrate embodiments of the disclosure that are not to be construed as limiting the scope of the disclosure in any manner. Additional features of the present disclosure will become apparent to those skilled in the art upon consideration of the following detailed description of illustrative embodiments exemplifying the best mode of carrying out the disclosure as presently perceived.
DETAILED DESCRIPTION
[0023] While the present disclosure may be susceptible to embodiment in different forms, the figures show, and herein described in detail, embodiments with the understanding that the present descriptions are to be considered exemplifications of the principles of the disclosure and are not intended to be exhaustive or to limit the disclosure to the details of construction and the arrangements of components set forth in the following description or illustrated in the figures.
[0024] FIGS. 1 and 2 show a plate press system 10 as an example four-cylinder plate press system that has been found useful with a single motor 12 . As such, each aligned plate press assembly 14 could operate at a quarter turn of a rotating crankshaft 16 , but other numbers and arrangements are within the scope of this system. A conveyor system 18 , which may be covered and heated as known in the art, can be used to remove substantially solid waste away from the plate press system 10 ,
[0025] At the exit ports 20 for solid waste, a pressure cone 22 controls flow of solid waste adjacent to its sloped sides 24 . The tip 26 of the pressure cone 22 preferably passes through the exit port 20 . Solid waste passes by the pressure cone 22 when pressure from the plate press system 10 overcomes the resistance of the pressure cone 22 , which can pivot on an arm 28 or otherwise resiliently move away from the exit port 20 . As shown in FIGS. 1 , 2 and 4 , a counterbalance 30 or series of pressure weights can provide initial pressure on the pressure cone 22 against the exit port 20 . The arm 28 as weighted can function via a hinge point 32 to apply pressure as needed to the pressure cone 22 against the exit port 20 . FIG. 4 shows five layers of pressure weights that can be used or removed as needed to adjust the weight and provide appropriate pressure, such as 25 pounds each layer with five layers total. It is contemplated that jugs finable with water can be used for such variable weights to adjust pressure on the pressure cone 22 . Similarly, springs or shock absorbers could be used to control acceleration and movement of the pressure cone 22 relative to the exit port 20 to allow substantially solid waste to depart the exit port 20 as pressure from waste in the cylinder 42 exceeds the force of the pressure cone 22 against the exit port 20 .
[0026] The plate press assembly 14 is built into a frame 34 that includes a receptacle 36 for initially inserting raw waste, such as a trough or chute extending above the frame 34 , which connects to a cylinder 38 , broadly defined as a passageway, to feed the waste into the plate press assembly 14 . The preferred cylinder 38 is used with a pumping and/or pressure means 40 , such as a piston 42 with a reciprocating plunger 44 , that forces waste under pressure through the cylinder 38 . A plunger 44 of a piston 42 can reciprocate within the near side of the cylinder 38 to push waste through the distal end 46 of the cylinder 38 into a series of plates 50 .
[0027] A series of plates 50 are spaced at the distal end 46 of the cylinder or otherwise in close association with the piston 42 pushing waste toward the series of plates 50 . The series of plates 50 each have an aperture 52 preferably in the center, like a doughnut hole, forming the continuing distal end 46 extending from or as part of the cylinder 38 for primary passage of the solid waste. The plates 50 are spaced to allow liquids to flow between the plates 50 , with extracted liquids generally being pulled downward by gravity to a collection area below the plates 50 .
[0028] In the example of FIG. 4 , the plate spacing between plates 50 next to the pressure cone 22 is wider. For example, the four plates 50 closest to the pressure cone 22 are spaced 0.135 inch, the next plates 50 are spaced 0.070 inch, the next plates 50 are spaced 0.045 inch and the four plates 50 closest to the piston 42 are spaced 0.030 inch. Also, it is contemplated that the apertures 52 in the plates 50 could get smaller as they get closer to the exit port 20 .
[0029] The pressure cone 22 blocks the exit port 20 until built up pressure of the waste and pressure from the piston 42 pushes the pressure cone 22 away from the exit port 20 so that substantially solid waste departs the exit port 20 adjacent to the sloped sides 24 of the pressure cone 22 . The pressure on the waste from additional waste being pressured from the piston 42 and the resistance of the pressure cone 22 helps squeeze liquids out of the waste to flow out between the plates 50 to a liquid collection area below the series of plates 50 .
[0030] The series of plates 50 can be adjusted for desired characteristics. For example, the number of plates 50 can be varied. The plate spacing can be adjusted for different viscosities of waste. It is understood that thicker plates can often withstand higher pressure, and for the manure example, a pressure of 15 tons is practical. Enormous pressure can squeeze the waste to achieve desired results of first extracting liquids via the plates 50 , then pushing solid waste out the exit port 20 .
[0031] The type of plates 50 can also be adjusted. For example, plastic plates can be used for applications with sand concerns, wherein sand is partially absorbed or pressed into the plates 50 making a sand surface that interacts with sandy waste materials. The built-up sand surface would not wear out as readily as metal with continuous sand abrasion. While likely too delicate for the example organic waste applications, the plate 50 could be glass for high tolerance delicate processes and for small molecule uses with very close plates, such as for medical applications.
[0032] After the substantially solid waste passes past the pressure cone 22 , it collects where the preferred conveyor system 18 can move the waste away from the plate press system 10 . The substantially solid waste as organics is generally dry enough to burn without activated carbon. Typically, the sand stays with the solids, rather than between the plates 50 , through the exit port 20 where sand separation equipments can vibrate sand through a screen or otherwise process the solids to a collector or compost or bedding area as a dried substantially solid waste product.
[0033] The liquids collected below the plates 50 may be of high nutrient value, and it may be further processed into a thicker slime. Such slime can be made into quality fertilizer with a pelletizer.
[0034] FIG. 3 shows an assembled view and FIG. 5 shows an exploded plate press assembly 14 with the components of the cylinder 38 with the receptacle 36 as a trough extending above, a plunger 44 of a piston 42 , the series of plates 50 for liquid extraction, an optional insert 54 that can aligned with the plate apertures 52 and cylinder 38 , and an exit port 20 .
[0035] It is contemplated that some material may jam between the plates 50 . Such materials can help filter liquids being extracted, and has not been found problematic if not left to dry out and harden. In a continuous process, any buildup on the plates 50 or between the plates 50 has not raised undue difficulties. At shut-down, however, the plates 50 are preferably cleaned. Thus, a high pressure water spray device or a knife system to clean between the plates 50 would be preferred complementary systems with the plate press system 10 .
[0036] The disclosed processes allow for separate extraction of solids and concentrated liquid nutrients from animal manure and food processing waste as the preferred examples.
PROCESS FOR EXTRACTING LIQUIDS FROM SOLIDS
[0037] Per FIGS. 1-5 , waste by-products are separated into solids and liquids by the mechanical plate press system 10 .
[0038] The liquid material extract can be directed over a heated, hooded or covered trough. As the liquids move through the trough, it is heated to its boiling point. Dried organic solids, from the plate press system 10 , can be used as a source of energy to produce heat. As the liquid boils, water evaporates into steam, which can be collected inside the hood and allowed to runoff or be captured as distillated water. The residual wastewater becomes a concentrated slim material rich in nutrients for use as concentrated fertilizer.
[0039] As can be derived from FIGS. 1-4 , the operational flow of the plate press system 10 for the treatment of waste, such as manure, can be as follows:
Step 1. Waste is pumped or inserted to the top of the plate press system 10 , such as via a receptacle 36 , where it enters the cylinder 38 . Step 2. A piston 42 , such as connected to a crankshaft 16 , moves the waste into the cylinder 38 where it is compressed. Step 3. The compressed waste is forced into the section of plates 50 of the plate press assembly 14 . Step 4. The pressure from the piston 42 causes liquids in the waste to seep through the plates 50 of the plate press assembly 14 . The liquids can be collected in a holding area, such as below the plates 50 , for further processing. Step 5. The pressure from the piston 42 causes the waste solids to seep past the pressure cone 22 and collect in the solids collecting area for further processing.
[0045] For manure or food as the waste, step 6 may include moving extracted liquids through a heated trough where liquid is allowed to evaporate leaving a concentrated slim fertilizer material.
[0046] For manure or food processing by-products as the waste, step 7 may include organic waste solid materials moved through or over a heated, covered or hooded conveyor system 18 where the solids are dried by forced air. During this process, temperatures can reach more than 160 degrees Fahrenheit, which kills bacteria in the solids. The dried organic solid material is available for animal bedding or returned to fields.
[0047] Organic solid material can be stacked in a compost pile and allowed to compost at temperatures more than 160 degrees Fahrenheit to kill bacteria and weed seeds. Composted materials are available for animal bedding or returned to fields.
[0048] The process and subsequent treatment, processing or use of extracted solids and liquids is meant to be a continuous process where continuing waste is pressed through the cylinder 38 and plates 50 .
[0049] The plate press process is not limited to waste or specifically manure as disclosed herein. It can be utilized for any organic material that requires separation of liquids and solids. The separate extraction of liquids via the plates 50 typically allows organics to be dry enough to burn or further process, including sand removal.
[0050] This disclosure has been described as having exemplary processes and is intended to cover any variations, uses, or adaptations using its general principles. It is envisioned that those skilled in the art may devise various modifications and equivalents without departing from the spirit and scope of the disclosure as recited in the following claims. Further, this disclosure is intended to cover such departures from the present disclosure as come within the known or customary practice within the art to which it pertains. | Systems and processes for extracting liquids and solids from waste include separately extracting liquids via spaced plates and solid waste out an exit pert with an operably counter pressured pressure cone. The system and process use a cylinder for accepting waste and a piston for providing pressure and pushing waste through the cylinder. Spaced plates with internal apertures are aligned with the cylinder, and pressure from the piston on waste in the apertures forces liquids to pass between the spaced plates. Solid waste egresses via an exit port aligned with the apertures when pressure on a pressure cone operably connected with the exit port exceeds the force keeping the pressure cone dosed on the exit port. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a CMOS image sensor, and more particularly, to a CMOS image sensor having two analog signal processors (ASP) for high-speed operation.
2. Description of the Prior Art
Image sensors, which can convert optical images to electrical signals, are classified into complementary metal oxide semiconductor (CMOS) image sensors and charge-coupled device (CCD) image sensors. For CCD image sensors, electric charges are transmitted to and stored in capacitors arranged close together. For CMOS image sensors, pixel arrays are formed in a CMOS integrated circuit process, and electric charges are detected sequentially by switch operations. The CMOS image sensor has a benefit of low power consumption, and is generally used in mobile communications devices.
Please refer to FIG. 1 . FIG. 1 is a diagram of a CMOS image sensor according to the prior art. The CMOS image sensor includes a pixel array 11 having red pixels (R), green pixels (G), and blue pixels (B) arranged in a matrix. A plurality of correlation double sampling (CDS) circuits 12 is arranged under the pixel array 11 , and each CDS circuit is coupled to a corresponding column of the pixel array 11 . An analog signal processor (ASP) 13 is arranged on a side of the pixel array 11 for processing output signals of the plurality of CDS circuits 12 .
The CDS circuit 12 samples the reset signal and the data signal from each pixel, and transmits the signals to the ASP 13 . Then, the ASP 13 calculates the difference of the reset signal and the data signal, and amplifies the signal to obtain image data of the object. In the process of reading the image data, one row of the pixel array 11 transmits the image data to the corresponding CDS circuits 12 . Finally, the output data of the CDS circuit 12 controlled by the driver 14 is transmitted sequentially to the ASP 13 .
As mentioned above, in the CMOS image sensor according to the prior art, when the one row of the pixel array is selected, the reset signals and the data signals of the pixels of the row are stored in the corresponding CDS circuits, and then the data of the corresponding CDS circuits controlled by the driver is transmitted sequentially to the ASP.
When the pixel array has over a million pixels, the number of CDS circuits increases with the number of pixels in each row. Since the bus for transmitting the data to the ASP is coupled to a large number of CDS circuits, the parasitic impedances of the bus are increased. Thus, the CMOS image sensor cannot operate at a high speed. For high-speed operation, the CMOS image sensor has to be improved, especially the ASP of the CMOS image sensor.
SUMMARY OF THE INVENTION
The present invention provides a complementary metal oxide semiconductor (CMOS) image sensor for high-speed operation comprising a pixel array comprising a plurality of first pixels, a plurality of second pixels, and a plurality of third pixels; a plurality of correlation double sampling (CDS) circuits coupled to corresponding columns of the pixel array; a selection circuit comprising a plurality of input ends coupled to each CDS circuit of the plurality of CDS circuits respectively, a first output end, and a second output end; a first analog signal processor (ASP) coupled to the first output end of the selection circuit for processing data of the plurality of first pixels and the plurality of second pixels; and a second analog signal processor (ASP) coupled to the second output end of the selection circuit for processing data of the plurality of third pixels.
The present invention provides a complementary metal oxide semiconductor (CMOS) image sensor for high-speed operation comprising a pixel array comprising a plurality of first pixels, a plurality of second pixels, and a plurality of third pixels; a switch circuit comprising a plurality of input ends coupled to corresponding columns of the pixel array, and a plurality of output ends; a plurality of correlation double sampling (CDS) circuits coupled to the plurality of output ends of the switch circuit respectively; an output circuit comprising a plurality of input ends coupled to each CDS circuit respectively, a first output end, and a second output end; a first analog signal processor (ASP) coupled to the first output end of the output circuit for processing data of the first pixels and the second pixels; and a second analog signal processor (ASP) coupled to the second output end of the output circuit for processing data of the third pixels.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of a CMOS image sensor according to the prior art.
FIG. 2 is a diagram of a first embodiment of a CMOS image sensor according to the present invention.
FIG. 3 is a timing diagram of a selection circuit in FIG. 2 .
FIG. 4 is a diagram of a second embodiment of a CMOS image sensor according to the present invention.
FIG. 5 is a diagram of a third embodiment of a CMOS image sensor according to the present invention.
FIG. 6 is a diagram of a fourth embodiment of a CMOS image sensor according to the present invention.
FIG. 7 is a diagram of a fifth embodiment of a CMOS image sensor according to the present invention.
DETAILED DESCRIPTION
Please refer to FIG. 2 . FIG. 2 is a diagram of a first embodiment of a complementary metal oxide semiconductor (CMOS) image sensor according to the present invention. The CMOS image sensor includes a pixel array 22 , a plurality of correlation double sampling (CDS) circuits 24 , a selection circuit 26 , a first analog signal processor (ASP) 28 , and a second ASP 30 . The pixel array 22 includes a plurality of first pixels R, a plurality of second pixels B, and a plurality of third pixels G. The plurality of third pixels G and the plurality of first pixels R are arranged alternately in odd rows of the pixel array 22 , and the plurality of second pixels B and the plurality of third pixels G are arranged alternately in even rows of the pixel array 22 . The plurality of CDS circuits 24 is coupled to corresponding columns of the pixel array 22 on the same side. The plurality of CDS circuits 24 can read data of one row of the pixel array 22 once. The CDS circuits basically include two groups of source followers. However, when outputting data, the CDS circuits have to drive all parasitic impedances of the internal switches because all of the output ends of the CDS circuit are in parallel. As the size of the pixel array 22 increases, for high-speed operation, large switches are used, but the parasitic impedance of the large switches will also limit the speed of the operation. Thus, a divided bus is utilized for reducing the parasitic impedance. In addition, the first pixels R, the second pixels B, and the third pixels G are arranged alternately in the pixel array 22 . To simplify signal processing, the first ASP 28 processes signals of the first pixels R and the second pixels B, and the second ASP 30 processes signals of the third pixels G.
Please refer to FIG. 3 . FIG. 3 is a timing diagram of the selection circuit 26 in FIG. 2 . T( 2 n−1) and T( 2 n) represent the operation of the odd rows and the even rows of the pixel array 22 , respectively. The selection circuit 26 divides the plurality of CDS circuits 24 into several groups to implement the divided bus. The selection circuit 26 includes a plurality of input ends coupled to each CDS circuit 24 , respectively, and transmits the data of the plurality of CDS circuits 24 to the first ASP 28 or the second ASP 30 . The first ASP 28 processes the data of the first pixels R and the second pixels B, and the second ASP 30 processes the data of the third pixels G. The first output end and the second output end of the selection circuit 26 are coupled to the first ASP 28 and the second ASP 30 , respectively. The selection circuit 26 includes eight switches S 1 -S 8 to divide the plurality of CDS circuits 24 into four divided buses. The switches S 1 and S 2 are regarded as a first divided bus 51 , and are coupled to the 4n−3th CDS circuits. The switches S 3 and S 4 are regarded as a second divided bus 52 coupled to the 4n−2th CDS circuits. The switches S 5 and S 6 are regarded as a third divided bus 53 coupled to the 4n−1th CDS circuits. The switches S 7 and S 8 are regarded as the fourth divided bus 54 coupled to the 4nth CDS circuits. The factor n is a positive integer. If each internal switch of the CDS circuits is the same, the parasitic loading will be reduced to ¼, so as to speed up the operation.
The timing diagram of the switches S 1 -S 8 is shown in FIG. 3 . When the plurality of CDS circuits 24 reads the data of the odd rows of the pixel array 22 , only the switches S 1 , S 4 , S 5 , and S 8 are turned on, so that the data of the first divided bus 51 and third divided bus 53 can be transmitted to the first ASP 28 , and the data of the second divided bus 52 and the fourth divided bus 54 can be transmitted to the second ASP 30 . When the plurality of CDS circuits 24 reads the data of the even rows of the pixel array 22 , only the switches S 2 , S 3 , S 6 , and S 7 are turned on, so that the data of the second divided bus 52 and fourth divided bus 54 can be transmitted to the first ASP 28 , and the data of the first divided bus 51 and third divided bus 53 can be transmitted to the second ASP 30 . As mentioned above, the third divided bus 53 and the first divided bus 51 can be combined into one path, and the fourth divided bus 54 and the second divided bus 52 can be combined into one path. However, the parasitic loading is reduced to ½ in the situation of two groups of divided busses, so the improvement is not as good. In the architecture of the CDS circuits 24 , the control signals of the divided busses 51 - 53 may overlap, but the divided busses can still operate normally, because each divided bus is independent of the other three divided busses. In addition, the switches S 1 , S 3 , S 5 , and S 7 can be turned off so as to use only the first ASP 28 for saving power consumption.
Please refer to FIG. 4 . FIG. 4 is a diagram of a second embodiment of a CMOS image sensor according to the present invention. In the second embodiment, the CMOS image sensor further includes a switch circuit 32 and an auxiliary CDS circuit 34 . In addition, the selection circuit 26 is replaced by an output circuit 36 . The switch circuit 32 is coupled between the pixel array 22 and the plurality of CDS circuits 24 . The auxiliary CDS circuit 34 is coupled between the switch circuit 32 and the output circuit 36 . The switch circuit 32 includes a first group of switches 33 and a second group of switches 35 . The first group of switches 33 couples the nth column of the pixel array 22 to the nth CDS circuit 24 , respectively. The second group of switches 35 couples the first column of the pixel array 22 to the auxiliary CDS circuit 34 , and couples the nth column of the pixel array 22 to the n−1th CDS circuit 24 . The factor n is a positive integer. The first group of switches 33 and the second group of switches 35 operate complementarily; that is, when one group of switches turns on, another group of switches turns off. The switch circuit 32 utilizes a shift method to transmit the data of the first pixels R, the second pixels B, and the third pixels G to the different CDS circuits 24 . For example, the pixel R in the second column of the odd row of the pixel array 22 is transmitted to the first CDS circuit 24 ; the pixel B in the first column of the even row of the pixel array 22 is transmitted to the first CDS circuit 24 ; the pixel G in the third column of the odd row of the pixel array 22 is transmitted to the second CDS circuit 24 ; the pixel G in the second column of the even row of the pixel array 22 is transmitted to the second CDS circuit 24 ; and the auxiliary CDS circuit 34 receives the pixel G in the first column of the odd row of the pixel array 22 . Thus, the output circuit 36 can output the data of the pixel array 22 to the first ASP 28 or the second ASP 30 directly without switches.
Please refer to FIG. 5 . FIG. 5 is a diagram of a third embodiment of a CMOS image sensor according to the present invention. The third embodiment does not use the auxiliary CDS circuit 34 , so the third embodiment has a different switch circuit 42 from the second embodiment. The switch circuit 42 includes a first group of switches 43 and a second group of switches 45 . The first group of switches 43 couples the mth column of the pixel array 22 to the mth CDS circuit 24 . The second group of switches 45 couples the 2n−1th column of the pixel array 22 to the 2nth CDS circuit 24 , and couples the 2nth column of the pixel array 22 to the 2n−1th CDS circuit. The factors m and n are positive integers. If the pixel array 22 has N columns, the factor m ranges from 1 to N, and the factor n ranges from 1 to N/2. Since the first pixels R, the second pixels B, and the third pixels G are arranged alternately in the pixel array 22 , the switch circuits 42 can transmit the data of the first pixels R, the second pixels B, and the third pixels G to the CDS circuits 24 alternately without the auxiliary CDS circuit 34 .
Please refer to FIG. 6 . FIG. 6 is a fourth embodiment of a CMOS image sensor according to the present invention. In the fourth embodiment, the CMOS image sensor includes a first group of CDS circuits 25 a and a second group of CDS circuits 25 b, which are arranged on a same side of the pixel array 22 . Utilizing two groups of CDS circuits gives flexibility for arrangement, because the CDS circuits require a large area. The operation of the fourth embodiment is similar to the second embodiment, utilizing the shift method to transmit the data of the pixel array 22 to the CDS circuits. A switch circuit 32 a has a first group of switches 33 a and a second group of switches 35 a. For the odd row of the pixel array, when the second group of switches 35 a turns on, the green pixels are transmitted to the second group of CDS circuits 25 b and the red pixels are transmitted to the first group of CDS circuits 25 a. For the even row of the pixel array, when the first group of switches 33 a turns on, the blue pixels are transmitted to the first group of CDS circuits 25 a and the green pixels are transmitted to the second group of CDS circuits 25 b. Finally, the data of the first group of CDS circuits 25 a are transmitted to the second ASP 30 through two divided buses, and the data of the second group of CDS circuits 25 a are transmitted to the first ASP 28 through two divided buses.
Please refer to FIG. 7 . FIG. 7 is a diagram of a fifth embodiment of a CMOS image sensor according to the present invention. In comparison with the third embodiment, the CMOS image sensor includes a first group of CDS circuits 24 a and a second group of CDS circuits 24 b, which are arranged on a same side of the pixel array 22 . In comparison with the fourth embodiment, the number of each group of CDS circuits 24 a and 24 b is one less than the number of each group of CDS circuits 25 a and 25 b of the fourth embodiment. For the odd row of the pixel array, when the first group of switches 43 turns on, the green pixels are transmitted to the first group of CDS circuits 24 a and the red pixels are transmitted to the second group of CDS circuits 24 b. For the even row of the pixel array, when the second group of switches 45 turns on, the blue pixels are transmitted to the second group of CDS circuits 24 b and the green pixels are transmitted to the first group of CDS circuits 24 a.
In summary, the CMOS image sensor according to the present invention includes two ASPs so as to reduce design difficulty due to the large size of the pixel array. In the first embodiment, the selection circuit transmits the red pixels and the blue pixels to the first ASP, and transmits the green pixels to the second ASP. In addition, the selection circuit utilizes four divided buses to output data of the plurality of CDS circuits, so as to reduce the parasitic loading and achieve high-speed operation. In the second embodiment and the third embodiment, the switch circuit is utilized to output the data of the red, blue, and green pixels of the pixel array to the separate CDS circuits. The switch circuit shifts the data of the pixel array to the CDS circuit with the auxiliary CDS circuit in the second embodiment. The switch circuit transmits the data of the pixel array alternately in the third embodiment. The switch circuit requires more switches than the selection circuit, but the requirements of the switches in the switch circuit are comparatively low, because the transmission speed from the pixel array is lower than transmission from the CDS circuits to the ASPs.
Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. | A CMOS image sensor having two ASPs can reduce increasing design difficulty as arising from a pixel array becoming larger and larger. The image sensor includes a selection circuit for transmitting outputs of CDS circuits through four divided buses to reduce parasitic loading and achieve high-speed operation. Then, the selecting circuit transmits red and blue pixels to a first ASP, and transmits green pixels to a second ASP, so as to relax the specification requirements of the ASP. | 7 |
BACKGROUND OF THE INVENTION
The field of this invention is the production of exhaust gases directly from the combustion chamber of internal combustion engines (especially diesel engines) for service as a nonflammable gas in the drilling and workover of oil and gas wells.
Nonflammable gases are used for a variety of applications in oil and gas wells including underbalanced drilling, geothermal drilling, lightening oil well fluids to initiate production, well cleaning, fracing and other well operations. These low cost nonflammable gases will have a variety of other applications in other markets such as purging lines, pigging pipelines, extinguishing fires, etc.
Historically, most of these operations have been done by an expensive cryogenic liquid nitrogen process. The proposed process have substantial economic and environmental advantages relative to the cryogenic nitrogen processes, however, the uses of internal combustion engine exhaust imposes certain requirements on the dehydration and cleaning of the gases.
SUMMARY OF THE INVENTION
The object of this invention is to provide means for the dehydration of gases extracted from the combustion chamber of internal combustion engines.
A second object of the present invention is remove particulate matter from the gases extracted from the combustion chamber of internal combustion engines.
A third object of the present invention is dispose of the water and particulate matter collected during the dehydration and cleaning processes of this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a an overall circuit drawing of a Baugas Service Gas System which incorporates and demonstrates the application of this invention.
FIG. 2 is a half section drawing of a dehydrator/filter system and associated control means.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, FIG. 1 is a an overall hydraulic circuit drawing of a service gas generation system which incorporates and demonstrates the application of this invention.
The system is built around a standard internal combustion engine 10, having a radiator 11, a block 12, pistons 13, valves 14, and a head 15. The engine can be a 2 cycle or 4 cycle engine, depending upon a variety of conditions. In this case some of the conventional exhaust valves 14 are replaced by riser tubes 20 which have extractor valves 21 installed on each of them.
During the normal compression cycle in the internal combustion engine the remaining exhaust valves 14 operate normally. The extractor valves 21 are manufactured to allow opening and production of some of the cylinder head gases past the extractor valve after the combustion has been initiated. During a portion of each rotation of the engine on 2 cycle engines or on every other rotation on a 4 cycle engine, hot gases will be produced past the valve means within the extractor valve assembly.
Produced gases are taken out line 30, thru converter 31, thru line 32, thru cooler 33, thru dehydrator/cleaner 34, and to the tee 35.
A portion of the cooled gases at tee 35 are taken thru line 40, thru recirculator pump 41, thru line 42, and back into the extractor valves 21. The constant recirculation caused by recirculator pump 41 causes cooled exhaust gases to be pumped across the extractor valves 21, giving a continuous cooling to the internal parts. Without the benefits of cooling techniques such as this, the temperatures of the high temperature produced gases are high enough to degrade the valve mechanisms.
The portion of the gases drawn off along line 50 from tee 35, thru control valve 51, thru flow rate meter 52, and along line 53 is the volume of gases delivered to the end user.
Secondary compressor system 60 and tertiary compressor system 65 utilize excess horsepower from the engine 10 thru the power takeoff assembly 70 to compress the produced gases to higher levels for various applications. For additional information on this compression process, refer to U.S. Pat. No. 5,276,838. Various service operations will require pressure as high as 5000 p.s.i. and 10,000 p.s.i. Produced gas can be taken thru outlet valves 71, 72, or 73, depending upon the secondary compression required for a particular application.
Fuel pump 80 draws fuel from the fuel tank used by engine 10 or from other fuel sources if a separate fuel or chemical injection is desired. This fuel is pumped along line 81 to converter 31. The fuel pump 80 is shown driven by shaft 82 off one of the drives on the rear of engine 10.
Oil pump 90 is shown driven by shaft 91 off one of the rear drives of engine 10 and drawing oil directly from the crankcase 92 of engine 10. The oil passes thru cooler 93, along lines 94-97 and into an annular circulation area 98 of the riser tubes 20. This oil serves to cool the riser tubes and then is vented into the head 15 of engine 10 and allowed to flow by gravity back to the crankcase 92.
Liquids separated from the produced gas by the dehydrator/cleaner 34 are taken by line 100 to the engine exhaust system 101 for revaporization as exhaust gas 102.
Now, referring to FIG. No. 2, the filter/dehydrator 34 has an inlet flow path 201, a body 202, an outlet 203, and gas swirling means 204. Collected liquids 205 which have condensed from the gases are shown up to a liquid level 206. In operation, the incoming gases, condensed liquids, and any particulate matter 210 would approach the condensed liquids 205 in the body 202 and turn sharply (arrow 211) to cause any liquids and any particulate matter to be entrained in the liquid 205.
Arrow 212 indicates the gases passing thru the swirling means 204 to assist in the cleaning and dehydration process and finally arrow 213 reflects cleaned and dehydrated gases approaching the outlet 203. The swirling action of the gas can be accomplished while travelling down, travelling up, or both; depending upon the particular application and equipment.
Control valve 220 attached to lower port 221 and controlled by controls circuitry 222 reflects a method for venting the liquids and entrained particulate matter into line 100 and thusly to exhaust system 101 as shown on FIG. No. 1. Upon entering the hot exhaust system 101 thru line 100, the liquids and entrained particulate matter will simply be revaporized and exit the system as exhaust gas 102.
Level sensing means 230 can be sonar or other means to determine when the level of the liquid has reached the maximum height desired and can signal the control valve 220 to open and exhaust some of the liquid. A likely type of level sensing means will be sonar, although floats and conductive sensors can work in some applications.
An alternate method which can be based upon experience will be to actuate the control valve 220 for a specific period of time on regular intervals. By this method, sensors prone to maintenance can simply be replaced by a simple timer.
The foregoing disclosure and description of this invention are illustrative and explanatory thereof, and various changes in the size, shape, and materials as well as the details of the illustrated construction may be made without departing from the spirit of the invention. | A method for dehydrating and cleaning high pressure gases withdrawn from within the combustion chamber of an internal combustion engine including maintaining the gases at a high pressure and cooling the gases to cause condensation of water, entraining particulate matter in the water, and delivering the water to the normal exhaust system of the engine for disposal thru vaporization back to being exhaust gas. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to an automatic delay equalizer, in particular, relates to an automatic delay equalizer for obtaining the desired equalizing characteristics, using the delay measured on a frequency axis and the amplitude of the cosine component generated in the control unit of the present equalizer.
A prior delay equalizer using a transversal filter adjusts the tap gain either manually or automatically through a complicated control process on a time axis.
However, when the tap gain of the equalizer is adjusted manually, it is difficult to obtain the optimum solution and it takes long time to reach the solution since the tap gain is adjusted just by guessing the quantity of the delay, without measuring the actual delay. And, a prior automatic delay equalizer using the control process on a time axis requires a very complicated control process since the tap gain is defined through the calculation of the correlation function between the input signal and the error.
SUMMARY OF THE INVENTION
It is an object, therefore, of the present invention to overcome the disadvantages and limitations of a prior equalizer by providing a new and improved automatic equalizer.
The above and other objects are attained by an automatic equalizer having a plurality of transversal filters each of which has an independent delay cosine equalization component having a predetermined period, and the superposition of those filters providing the desired characteristics, characterized in that, said equalizer further comprises a Bessel function generator for controlling the tap gain of said transversal filters.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features, and attendant aadvantages of the present invention will be appreciated as the same become better understood by means of the following description and the accompanying drawings wherein;
FIG. 1 shows the circuit diagram of the Bessel function type automatic equalizer according to the present invention,
FIG. 2 shows the block-diagram of the Bessel function generator;
FIG. 3 shows the other embodiment of the automatic equalizer according to the present invention; and
FIG. 4 is the block-diagram of the negative pair type transversal filter (TF 6 ) 40 in FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is the circuit-diagram of the automatic equalizer according to the present invention, and FIG. 2 is the block-diagram of the Bessel function generator for the apparatus of FIG. 1. In FIG. 1, T - (N-),,,, T -3 , T -2 , T -1 , T 1 , T 2 , T 3 ,,, T.sub.(N-1) are delay lines each of which has the same delay time τ and C - (N<1),,,, C -3 , C -2 , C -1 , C 0 , C 1 , C 2 , C 3 ,,,, C.sub.(N-1) are variable gain circuits each of which is connected to the related tap of the delay line. The input digital signal applied to the input terminal (IN) passes through the train of delay lines T - (N-1) through T.sub.(N-1), and the tap outputs of the train of delay lines are applied to the variable gain circuits which control the amplitude of the digital signal. The outputs of the variable gain circuits are added to one another in the adder (Σ), the output of which appears at the output terminal (OUT) as the output of the present equalizer. The gain of the variable gain circuits are controlled by the Bessel function J N-1 (X 1 ),,,, J 3 (X 1 ), J 2 (X 1 ), J 1 (X 1 ), J 0 (X 1 ), applied to the variable gain circuits from the Bessel function generator. The inverter (I) is inserted in the odd variable gain circuits as shown in FIG. 1.
The operation of the apparatus in FIG. 1 is mathematically explained below.
The transfer function of X 1 is ##EQU1## The formula (2) can be changed to; ##EQU2## The formula (3) shows that the transfer function of the formula (1) can be realized by a transversal filter whose tap gain is defined by the Bessel function, that is to say, J 0 (X 1 ) for the center tap, the positive pair of the Bessel function to the even number of taps, and the negative pair of the Bessel function the odd number of taps. FIG. 1 is, it should be appreciated, the circuit for realizing the formula (3).
From the formula (1), the phase characteristics and the delay characteristics are given by the formulas (4) and (5) respectively.
argK.sub.1 (jω) = -X.sub.1 sin(τω) (4)
The delay characteristics is ##EQU3## Further, the formula (6) is derived from the formula (2). ##EQU4## It should be noted that the formula (6) shows the delay chatacteristics according to the Bessel function, and the formula (6) is equivalent to the formula (5). When an equalizer is composed in accordance with the formula (6) using a transversal filter with (2N-1) taps, the addition in the adder (Σ) in FIG. 1 is performed up to the (N-1)'th term, then the rest of the terms may cause the error in view of the formula (5).
The formula (3) shows that the even terms have a positive coefficient, and the odd terms have a negative coefficient. Therefore, an inverter is inserted in the odd term circuit, and thus the N number of the Bessel function values provide the (2N-1) number of the tap gains.
It should be understood of course that equalization elements having a period of 1/2, 1/3 or l/k can be realized in a similar manner as described above.
FIG. 1 shows that the whole circuit is a series connection of the transversal filters each of which shares the relating equalization of the delay.
The transfer function of FIG. 1 constructed above is shown in the formula (7) below. ##EQU5## where X i is the amplitude of the i'th phase component. The phase characteristics θ(ω) and the delay characteristics T(ω) are shown below. ##EQU6##
The formula (9) can be changed to the matrix form below, where the sampled values on the frequency axis with the same intervals to one another are denoted T(ω 1 ), T.sub.(ω 2 ),,,, T(ω N-1 ) ##EQU7##
The equation (10) is solved as shown in the formula (11), where the cosine matrix has an additional row and column in order that said cosine matrix is a regular matrix. By obtaining the measured value T(ω 0 , T(ω 1 ), T(ω 2 ),,,,T(ω N-1 ), the value (X 0 , X 1 , X 2 , - - - - , X N-1 ) T can be obtained from the formula (11). ##EQU8##
The Bessel function is generated as explained below from the vector (X 1 , X 2 ,,,, X N-1 ) which relates to the amplitude of the phase component obtained according to the formula (11), and said Bessel function is applied to the transversal filters.
Generally speaking, the Bessel function is obtained from the following formula. ##EQU9##
Further, it should be appreciated that the first and second terms of the formula (12) can provide all of the Bessel function by introducing the following asymptotic formula. ##EQU10##
FIG. 2 shows the block-diagram of the Bessel function generator according to the present invention. In the figure, the reference numeral 100 is the input terminal, 10 is the basic component generator for obtaining ρ=0, and ρ=1 in the formula (13), and has the box 11 for generating J 0 (X), and the box 21 for generating J 1 (X). 12 is the signal line for J 0 (X), 22 is the signal line for J 1 (X), 13 is the high-order term generator for generating ν=1, ν=2, ,,, from the formula (13), and 14 is the signal line for J 84+1 (X). 15 is the shift register for storing J 0 (X), J 1 (X), J 2 (X),,,, J.sub.(N-1) (X).
Although J.sub.ρ (X) in the formula (12) has an infinite number of terms, the circuit 10 is sufficient to calculate a finite number of terms, however, the calculation error, is neglected, since the value of the denominator K!(ρ+ k) ! increases rapidly according to the increase of the value k, and thus the terms of high-order can be neglected.
FIG. 3 shows the other embodiment of the present equalizer, in which both a plurality of Bessel type equalizers TF 1 through TF 5 and the conventional negative pair type equalizer TF 6 are utilized, thus the structure of the whole circuit of the equalizer is simplified. The reason for this is explained below.
When the voice channel is equalized, the delay information sampled for every 200 H z interval and the equalization at the sampled points are sufficient for practical purposes. Supposing that the period of the basic equalization is from D.C. to 7200 H z , then the equalization band is 3600 H z and the number of sampling points is 17. Accordingly, the number of variables X k of the Bessel function is also 17. In that case, the number of taps required for the transversal filter is at least 35 (17 taps on the negative side and 17 taps on the positive side and a single tap at the zero point), supposing that at least a single tap is used on either the negative or positive side, that tap actually has the function J 1 (X 17 ), in relation to the generation of the equalization component having the smallest period among the above 17 Bessel functions. A transversal filter is required in each equalization component, thus the number of transversal filters required is seventeen, each having thirty-five taps, that number and taps is, however, too large for practical applications.
It should be appreciated that the negative pair type equalizer is excellent for the equalization of high-order equalization components although the equalization capability of the same is not sufficient for the basic equalization component and the component having one-half of one-third period of the basic component, while the Bessel function type delay equalizer is excellent for all of the equalization components although the number of the taps is too large if the Bessel function type equalizer is applied to the equalization of high-order harmonic components.
When the Bessel function type equalizer is utilized for equalization of the basic component through one-fifth of the period of the same, and the negative pair type equalizer is utilized for the rest of the components, the number of taps required is only 210 as shown below.
35 × 5 + 35 × 1 = 210
However, it should be noted that the equalizer of FIG. 3 can be utilized only when the amplitude ε ni of the phase component is small.
The operation of the equalizer of FIG. 3 is explained below. The input terminal 1 is connected to the contact (a) so long as the pilot signal is transmitted, and thus the input signal is applied to the digital analyzer 31, which stores the measured results measured at the uniform intervals on the frequency axis in the memory 32.
The minimum value detector 33 detects the minimum value among the results stored in the memory 32, and the detected minimum value is subtracted from each value stored in the memory 32. The inverse delay equalization characteristics are obtained by subtracting the difference of said subtraction from the predetermined equalization interval S.
Among the inverse delay equalization characteristics, the negative value is forced to zero by the clip circuit 34, the output of which is T(ω j ) in the formula (11).
On the other hand, the inverse matrix memory 36 has the inverse matrix of the formula (11), and the weight matrix memory 35 has the inverse matrix concerning τ, and the product of the outputs of the memorys 35 and 36 is multiplied with said T(ω j ), and the (X 1 X 2 ,,,, X N-1 ) T is obtained as the product of the multiplication. In the figure, the symbol M shows the multiplier. Among them, X 1 , X 2 X 3 X 4 , and X 5 are stored in the memory 38 through the AND-circuit 37, and the rest of them are applied to the transversal filter 40 as the tap gain of the negative pair.
The value X i stored in the memory 38 is applied to the J.sub.ρ (X) generator shown in FIG. 2. Said generator 39 applies J 0 (X 1 ), J 1 (X 1 ), ---- J.sub.(N-1) (X 1 ) to the transversal filter (BES. 1), applys J 0 (X 2 ), J 1 (X 2 )----- J.sub.(N-1) (X 2 ) to the transversal filter (BES. 2), and similarly applies J 0 (X 5 ), J 1 (X 5 ) ---- J.sub.(N-1) (X 5 ) to the transversal filter (BES. 5). Thus the tap adjustment of those transversal filters is accomplished. After the completion of the tap adjustment, the switch SW is connected to the contact (b), and then the input signal applied to the terminal 1 is equalized by the transversal filters TF 1 through TF 6 and the equalized signal is provided at the output terminal 2.
FIG. 4 shows the block-diagram of the transversal filter (TF 6 ) 40 in FIG. 3. The elements composing the apparatus of FIG. 4 are exactly the same as those of FIG. 1. However, the apparatus of FIG. 4 has the feature that the tap gain of the center tap is 1 and the tap weight ε n6 , ε n7 ---- ε n17 for more than 6'th taps constitutes the negative pair type transversal filter, where
ε.sub.ni = 1/2 X.sub.k.
The automatic delay equalizer as mentioned above can realize the transfer function ##EQU11## and so the equalization capability is excellent.
Further, the number of taps can be reduced with a little compromise of the equalization capability. Further, the combination structure that the Bessel function type equalizer handles the larger value of X i , and the negative pair tap type equalizer handles the smaller value of X i .
It should be appreciated that many modifications of the present embodiments are possible, for instance, the portion enclosed by the dotted line in FIG. 3 can be a separate unit, which is commonly composed of a plurality of delay equalizers, in order to simplify the structure of the equalizer.
From the foregoing it will now be apparent that a new and improved automatic delay equalizer has been found. It should be appreciated of course that the embodiments disclosed are merely illustrative and are not intended to limit the scope of the invention. Reference should be made to the appended claims, therefore, rather than the specification as indicating the scope of the invention. | A Bessel function type automatic delay equalizer comprising a plurality of transversal filters each of which has an independent delay cosine equalization component having a predetermined period, and the superposition of those filters providing the desired characteristics, characterized in that, said equalizer further comprises a Bessel function generator for controlling the tap gain of said transversal filters. | 7 |
This application is a continuation-in-part of application Ser. No. 175,330 filed Dec. 29, 1993, now abandoned.
FIELD OF THE INVENTION
The present invention is directed to a water-dispersible adhesive composition. More particularly, the present invention is directed to a hot melt adhesive composition that, due to its water-dispersibility, is repulpable, allowing paper products, nonwoven assemblies, and other disposable products to be more effectively recycled. The present invention is also directed to a hot melt adhesive composition containing polyester that is water dispersible while maintaining excellent adhesive properties.
BACKGROUND OF THE INVENTION
Many adhesives including hot melt adhesives are useful for bonding various substrates together such as wood, paper, plastics, and textiles, as well as other materials. One use for which hot melt adhesives are well suited is the fabrication of corrugated paper board. Hot melt adhesives, useful for producing corrugated paper board, must have high bond strength under conditions of shock, stress, high humidity, and extremes of temperature encountered in transportation and storage. In addition, the melt point, wetting time, initial tack, setting time, pot life, and general handling qualities on automatic corrugated board machinery are essential considerations.
At present, it is very desirable to recycle paper, paper products, and other disposable products to conserve material resources and to avoid large additions to landfill space. It is thus a general practice in the paper industry to recover the used and waste corrugated material and repulp the material for use in the preparation of other materials such as cardboard. The use of polyolefin hot melt adhesives to close or seal cartons made from corrugated material has presented problems in regard to repulpability of the used boxes or cartons (see U.S. Pat. Nos. 4,070,316; 4,127,619; 4,146,521; 4,460,728; 4,471,086; and 4,886,853). In fact, all the presently available hot melt and pressure sensitive adhesives are largely water insoluble and very difficult to disperse during the repulping process. This fact makes certain paper products, in which adhesives are necessarily utilized, unattractive since failure to disperse the insoluble adhesives results in lower quality recycled paper having variable composition and nonuniformity and thus, lower product value.
One approach to avoid the presence of insoluble adhesives in the recycled paper products is to use adhesives whose density is different from the density of water and pulp in water, thus permitting gravitational separation. However, this requires separation steps which can increase the recycling costs of the paper products containing adhesives.
Another approach could be to use a water soluble adhesive that would be separated from the pulp and dispersed into the water during repulping. This type of adhesive would remain in the water when the pulp is recovered. However, presently available water soluble or dispersible adhesives are "natural" adhesives such as dextrins, cellulose gums, and animal glues derived from the hides and bones of animals and these adhesives have lower strength, fail to adhere well to paper and wood stocks with coatings or heavy ink applications, and sometimes require special treatment and handling because of their high viscosity. Therefore, the use of these adhesives, while being easily recyclable, is quite low due to poor adhesive characteristics. Attempts to produce synthetic water-dispersible hot melt adhesive compositions have heretofore been unsuccessful due to resulting poor adhesive properties such as thermal stability, low strength, poor viscosities and low cold flow resistance. Additionally, costs and ease in manufacturing have precluded their use (see U.S. Pat. Nos. 3,919,176 and 5,098,962).
In addition to paper and paper products, there are many disposable products, such as diapers, in which hot melt adhesives are used. The use of current hot melt adhesives in these products complicate attempts to recycle products and separate out the insoluble sticky hot melt adhesives.
In light of the above, it would be very desirable to produce a water-dispersible adhesive, particularly a hot melt adhesive, at reasonable costs that maintains the desirable properties of presently available adhesives.
SUMMARY OF THE INVENTION
The water-dispersible adhesive composition according to the present invention comprises a branched water-dispersible polyester composition made of the residues or moieties of reaction products;
(I) at least one difunctional dicarboxylic acid which is not a sulfomonomer;
(II) about 2 to 15 mol percent, based on the total of all acid, hydroxyl and amino equivalence, of residues of at least one difunctional sulfomonomer containing at least one sulfonate group bonded to an aromatic ring wherein the functional groups are hydroxyl, carboxyl, or amino;
(III) at least one diol or a mixture of a diol and a diamine comprising:
(A) about 0.1 to 85 mol percent, based on the total mol percent of diol moieties or diol and diamine moieties, of a diol or diamine having the formula H(--OCH 2 CH 2 --) n OH and HRN(.paren open-st.CH 2 CH 2 O .paren close-st.) n NHR wherein n is 2 to about 20 and R is hydrogen or C 1 -C 6 alkyl provided that the mol percent of such moieties is inversely proportional to the value of n;
(B) about 0.1 to 15 mol percent, based on the total mol percent of diol moieties or diol and diamine moieties, of moieties of a poly(ethylene glycol) having the formula H(--OCH 2 CH 2 --) n OH wherein n is 2 to about 500, provided that the mol percent of such moieties is inversely proportional to the value of n; and
(C) 0 to greater than about 99 mol percent of the diol component or diol and diamine mixture being selected from the group consisting of a glycol and a mixture of glycol and diamine having two --NRH groups, the glycol containing two --C(R 1 ) 2 --OH groups wherein R 1 in the reactant is a hydrogen atom, an alkyl of 1 to 5 carbon atoms, or an aryl group of 6 to 10 carbon atoms;
(IV) 0 to about 40 mol % of a difunctional monomer reactant selected from the group consisting of hydroxycarboxylic acids having one --C(R--) 2 --OH group, aminocarboxylic acids having one --NRH group, aminoalkanols having one --C(R--) 2 OH group and one --NRH group and mixtures of said difunctional reactants wherein R in the reactant is hydrogen or an alkyl group of 1 to 6 carbon atoms; and
(v) about 0.1 to 40 mol % of a "multifunctional" or "branch-inducing" reactant containing at least three functional groups selected from hydroxyl, carboxyl, amino, and mixtures thereof;
the polymer containing substantially equal mol proportions of acid equivalents (100 mol %) and diol or diol and diamine equivalents (100 mol %) wherein at least 20 weight percent of the groups linking the moieties of the monomeric units are ester linkages and wherein the inherent viscosity is at least 0.1 dL/g measured in a 60/40 parts by weight solution of phenol/tetrachloroethane at 25° C. and at a concentration of about 0.25 g of polymer in 100 ml of the solvent, the glass transition temperature T g is no greater than 20° C., and the ring and ball softening point is at least 70° C. Alternatively, the water-dispersible adhesive composition according to the present invention can be a blend of two different polyesters that comprises:
(1) about 20 to 80 weight percent of the linear water-dispersible polyester composition made of the residues or moieties of reaction products;
(i) at least one difunctional dicarboxylic acid which is not a sulfomonomer;
(ii) about 4 to 25 mol percent, based on the total of all acid, hydroxyl and amino equivalence, of residues of at least one difunctional sulfomonomer containing at least one sulfonate group bonded to an aromatic ring wherein the functional groups are hydroxyl, carboxyl, or amino;
(iii) at least one diol or a mixture of a diol and a diamine comprising:
(A) at least 15 mol percent, based on the total mol percent of diol moieties or diol and diamine moieties, of a diol or diamine having the formula H(--OCH 2 CH 2 --) n OH and HRN.paren open-st.CH 2 CH 2 O.paren close-st. n NHR wherein n is 2 to about 20 and R is hydrogen or C 1 -C 6 alkyl,
(B) about 0.1 to less than about 15 mol percent, based on the total mol percent of diol moieties or diol and diamine moieties, of moieties of a poly(ethylene glycol) having the formula H(--CH 2 CH 2 --) n OH wherein n is 2 to about 500, provided that the mol percent of such moieties is inversely proportional to the value of n; and,
(iv) 0 to about 40 mol percent moieties of a difunctional monomer reactant selected from hydroxycarboxylic acids, aminocarboxylic acids and aminoalkanols; the polymer containing substantially equal mol proportions of acid equivalents (100 mol %) and diol or diol and diamine equivalents (100 mol %) wherein at least 20 weight percent of the groups linking the moieties of the monomeric units are ester linkages and wherein the inherent viscosity is at least 0.1 dL/g measured in a 60/40 parts by weight solution of phenol/tetrachloroethane at 25° C. and at a concentration of about 0.25 g of polymer in 100 ml of the solvent; and
(2) about 20 to 80 weight percent of the branched water-dispersible polyester made of the moieties of reaction products;
(a) at least one difunctional dicarboxylic acid which is not a sulfomonomer;
(b) about one to 20 mol percent, based on the total of acid, hydroxyl and amino equivalents, of residues of at least one difunctional sulfomonomer containing at least one sulfonate group bonded to an aromatic ring wherein the functional groups are hydroxyl, carboxyl, or amino;
(c) at least one difunctional reactant selected from a glycol or a mixture of glycol and diamine having two --NRH groups, the glycol containing two --C(R 1 ) 2 --OH groups wherein R in the reactant is hydrogen or an alkyl group of 1 to 6 carbon atoms, and R 1 in the reactant is a hydrogen atom, an alkyl of 1 to 5 carbon atoms, or an aryl group of 6 to 10 carbon atoms;
(d) 0 to about 40 mol % of a difunctional reactant selected from hydroxycarboxylic acids having one --C(R--) 2 --OH group, aminocarboxylic acids having one --NRH group, amino-alcohols having one --C(R--) 2 --OH group and one --NRH group, or mixtures of said difunctional reactants wherein R in the reactant is hydrogen or an alkyl group of 1 to 6 carbon atoms; and
(e) 1 to 40 mol % of a "multifunctional" or "branch-inducing" reactant containing at least three functional groups selected from hydroxyl, carboxyl, amino, and mixtures thereof;
wherein all stated mol percents are based on the total of all acid, hydroxyl, and amino group containing reactants being equal to 200 mol percent, and wherein the polymer containing a portion of the acid-group containing reactants (100 mol percent acid) to hydroxyl and amino-group containing reactants (100 mol %).
The present invention also further comprises a process of applying the above water-dispersible adhesive composition between two substrates to form a laminate. The adhesive can later be separated from the substrates in recycling by repulping the entire laminate structure. This invention comprises applying the above water-dispersible adhesive composition in liquid form to a surface of a substrate and, while remaining in the liquid form, applying a second surface of a substrate to the water-dispersible adhesive composition thereby forming an article of manufacture that comprises the water-dispersible adhesive composition laminated between two substrates or two surfaces of a substrate.
The present invention also comprises the bonded articles of manufacture having the adhesive composition between two substrates such as in carton sealings, corrugated board and diaper construction.
DETAILED DESCRIPTION OF THE INVENTION
The applicants have unexpectedly discovered an improved adhesive composition that can be applied as a liquid dispersion (aqueous or solvent) on substrates as well as by hot melt application. The inventive adhesive composition not only has good aqueous adhesive properties but also has excellent hot melt adhesive properties and is totally recyclable when the products containing the adhesive are recycled by repulping. The present adhesive composition is easily repulpable and removed from the fibers from paper or wood pulp used in disposable products, particularly in the preferred hot melt applications. The adhesive according to the present invention permits recycling of disposable products at significantly reduced processing costs without affecting the physical properties of the adhesive and resulting article.
Certain water-dispersible polyester compositions are described in detail in U.S. Pat. Nos. 3,734,874; 3,779,993; 4,233,196; and 4,335,220, the disclosures of which are incorporated herein by reference in their entirety.
The water-dispersible adhesive composition according to the present invention that can be a single polyester is a branched water-dispersible polyester made of the residues or moieties of reaction products; (I); (II); (III); (IV) and (V) above.
Alternatively, the water-dispersible adhesive composition according to the present invention is a blend of two different polyesters that comprises: (1) about 20 to 80 weight percent of the linear water-dispersible polyester composition made of the residues or moieties of reaction products; (i); (ii); (iii); and (iv) above and (2) about 20 to 80 weight percent of the branched water-dispersible polyester made of the moieties of reaction products; (a); (b); (c); (d); and (e) above.
Although the inventive single polyester water-dispersible adhesive composition and the inventive water-dispersible adhesive composition that is a blend of two different polyesters have different amounts of monomers and a different mix of groups of monomers, some specific groups of suitable monomers and preferred monomers of these groups are the same as is illustrated below.
The sulfonate-containing, water-dispersible, adhesives and polyesters of this invention comprise polyesters, including polyesteramides, having repeating, alternating residues or moieties of one or more dicarboxylic acid which is not a sulfomonomer and one or more diols or a combination of one or more diols and one or more diamines wherein the mol percentages are based on 100 mol percent dicarboxylic acid residues and 100 mol percent diol or diol and diamine residues, for a total of 200 mol percent. Alternatively, the polyesters can include residues of monomers having mixed functionality such as hydroxycarboxylic acids, aminocarboxylic acids and/or aminoalkanols.
Examples of suitable difunctional dicarboxylic acid monomers used to make the residue of (I), (i), and (a) include aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, aromatic dicarboxylic acids, or mixtures of two or more of these acids. Examples of preferred suitable dicarboxylic acids include succinic; glutaric; adipic; azelaic; sebacic; fumaric; maleic; itaconic; 1,4-cyclohexanedicarboxylic; 1,3-cyclohexanedicarboxylic; phthalic; terephthalic; and isophthalic. If terephthalic acid is used as the dicarboxylic acid component of the polyester, superior results are achieved when at least 5 mol percent of one of the other acids is also used. It should be understood that the use of the corresponding acid anhydrides, esters, and acid chlorides of these acids is included in the term "dicarboxylic acid".
The difunctional sulfo-monomer component of (II), (ii), and (b) is preferably a dicarboxylic acid or ester thereof containing a metal sulfonate group or a glycol containing a metal sulfonate group or a hydroxy acid containing metal sulfonate group. The cation of the sulfonate salt can be NH 4 + , or the metal ions Li + , Na + , K + , Mg ++ , Ca ++ , Cu ++ , Ni ++ , Fe ++ , Fe +++ and the like.
Residue or reactant (II), (ii), and (b) in the polyester of the present invention is a difunctional monomer containing a --SO 3 M group attached to an aromatic nucleus, wherein M is hydrogen NH 4 + , or a metal ion. The difunctional monomer component may be either a dicarboxylic acid or a diol adduct containing a --SO 3 M group. The cation of the sulfonate salt group can be NH 4 + , or the metal ions Li + , Na + , K + , Mg ++ , Ca ++ , Cu ++ , Ni ++ , Fe ++ , Fe +++ and the like. Preferred are monovalent cations, such as NH 4 + , Li + , Na + , and K + , when stability in water is desired.
The --SO 3 M group is attached to an aromatic nucleus, examples of which include benzene, naphthalene, anthracene, diphenyl, oxydiphenyl, sulfonyldiphenyl, and methylenediphenyl.
The cationic portion of a nonmetallic sulfonate group optionally present in reactant (II), (ii), and (b) is a nitrogen-based cation derived from nitrogen-containing bases which may be aliphatic, cycloaliphatic or aromatic basic compounds that have ionization constants in water at 25° C. of 10 -3 to 10 -10 preferably 10 -5 to 10 -8 . Especially preferred nitrogen-containing bases are ammonia, dimethylethanolamine, diethanolamine, triethanolamine, pyridine, morpholine, and piperidine, due to availability, cost, and usefulness. Such nitrogen-containing bases and cations derived therefrom are described in U.S. Pat. No. 4,304,901, the disclosure of which is incorporated herein by reference in its entirety.
It is preferred that reactant (II) be present in a concentration of about 4 to 12 mol percent, more preferably about 6 to 10 mol percent, with a mol percent of about 8 being most preferred based on total acid equivalents. At amounts below 4 mol percent the polyester is less repulpable whereas at amounts above 12 mol percent the polyester is a little too water-sensitive.
It is preferred that reactant (ii) and, independently, reactant (b) be present in an amount of 2 to 25 mol percent, more preferably about 4 to 15 mol percent, based on the total acid equivalents.
Examples of preferred diols of (III) (A) and (iii) (A), due to availability, include diethylene glycol, triethylene glycol, and mixtures thereof. The preferred concentration of (III) (A) is about 10 to 80 mol percent, however, when these are the preferred diols of (III) (A) the concentration is about 20 to 80 mol percent. At amounts outside this range of 20 to 80 the polyesters have lower softening points and higher Tg than what is most desired.
The moieties of (III) (A) and (iii) (A) can be the same as (III) (B) and (iii) (B), respectively, when the value n is low. However, it is preferred that (B) be a different moiety and be a poly(ethylene glycol). Examples of suitable poly(ethylene glycols) of (III) (B) and (iii) (B) include relatively high molecular weight polyethylene glycols, some of which are available commercially under the designation "Carbowax", a product of Union Carbide. Poly(ethylene glycols) having molecular weights of from about 500 to about 5000 are especially suitable.
The moieties of (B) are preferably at a concentration of about 1 to 5 mol percent, particularly when n is 10 to 30, due to the preferably higher softening points. The remaining portion of the glycol component of (III), (iii), and (c) can consist of aliphatic, alicyclic, and aralkyl glycols. Examples of these glycols include neopentyl glycol; ethylene glycol; propylene glycol; 1,3-propanediol; 2,4-dimethyl-2-ethylhexane-1,3-diol; 2,2-dimethyl-1,3-propanediol; 2-ethyl-2-butyl-1,3-propanediol; 2-ethyl-2-isobutyl-1,3-propanediol; 1,3-butanediol; 1,4-butanediol; 1,5-pentanediol; 1,6-hexanediol; 2,2,4-trimethyl-1,6-hexanediol; thiodiethanol; 1,2-cyclohexanedimethanol; 1,3-cyclohexanedimethanol; 1,4-cyclohexanedimethanol; 2,2,4,4-tetramethyl-1,3-cyclobutanediol; p-xylylenediol and neopentyl glycol. Copolymers may be prepared from two or more of the above glycols. Preferred glycols, due to availability, cost, and usefulness, include neopentyl glycol, ethylene glycol, 1,3-propane diol, 1,4-butane diol, 1,6-hexane diol and cyclohexane dimethanols.
Advantageous examples of difunctional monomer component of (III) and (c) which are diamines include ethylenediamine; hexamethylenediamine; 2,2,4-trimethylhexamethylenediamine; 4-oxaheptane-1,4-diamine, 4,7-dioxadecane-1,10-diamine; 1,4-cyclohexanebismethylamine; 1,3-cyclohexanebismethylamine; heptamethylenediamine; dodecamethylenediamine, etc.
The amount of the moieties III (C) present in the polyester is preferably a minor amount up to about 99 mol percent, more preferably 20 to 80 mol percent with a mol percent of about 30 to 70 being more preferred due to the preferred balance between the desired low Tg and the desired high softening point.
Advantageous difunctional components which are aminoalcohols or aminoalkanols include aromatic, aliphatic, heterocyclic, and other types in regard to component (IV), (iv) and (d). Specific examples include 5-aminopentanol-1,4-aminomethylcyclohexanemethanol, 5-amino-2-ethyl-pentanol-1, 2-(4-β-hydroxyethoxyphenyl)-1-aminoethane, 3-amino-2,2-dimethylpropanol, hydroxyethylamine, etc. Generally these aminoalcohols contain from 2 to 20 carbon atoms, one --NRH group and one --CR 2 --OH group.
Advantageous difunctional monomer components which are aminocarboxylic acids include aromatic, aliphatic, heterocyclic, and other types in regard to component (IV), (iv), and (d) and include lactams. Specific examples include 6-aminocaproic acid, its lactam known as caprolactam, omega aminoundecanoic acid, 3-amino-2-dimethylpropionic acid, 4-(β-aminoethyl)benzoic acid, 2-(β-aminopropoxy)benzoic acid, 4-aminomethylcyclohexanecarboxylic acid, 2-(β-aminopropoxy)cyclohexanecarboxylic acid, etc. Generally, these compounds contain from 2 to 20 carbon atoms.
These moieties (IV) (iv) and (d) are less preferred, due to cost and performance, but they can be present. The concentration of these moieties is preferably below 20 mol percent, more preferably below 10 mol percent, including zero.
Preferred water dispersible linear polyesters of (1) in the polyester blend contain diacid monomer residues that are about 75 to 90 mol percent isophthalic acid residues, and about 10 to 25 mol percent 5-sodiosulfoisophthalic acid monomer residues; and diol monomer residues of about 45 to 100 mol percent diethylene glycol monomer residues and 0 up to 55 mol percent 1,4-cyclohexanedimethanol.
The more preferred water dispersible linear polyesters of (1) have an inherent viscosity of 0.1 to 0.6, preferably 0.2 to 0.5, and a Tg range of about 25° to 88° C., preferably about 29° to 55° C.
The branched water dispersible polyester of (2) is made of the moieties of the reaction products (a), (b), (c), (d), and (e) above.
Related branched water-dispersible polyesters of (2) above are disclosed in U.S. Pat. No. 5,218,042, the disclosure of which is incorporated herein by reference in its entirety. U.S. Pat. No. 5,218,042 is directed towards increasing the stability of dispersions in water and thus endcaps the acid groups or forms a diol adduct of a dicarboxylic sulfomonomer to maintain dispersion stability. However, the present inventive compositions are not directed towards maintaining a stable emulsion, simply producing an emulsion by pulping and dissolving the hot-melt adhesive in water until it is separated from the fibers. Therefore, endcapping and forming a diol adduct of the sulfomonomer is not a requirement for the present invention.
The polyester compositions are branched by virtue of the presence of a multifunctional reactant (V) and (e) that contains at least three functional groups selected from hydroxyl, carboxyl, and amino. Examples of preferred multifunctional reactants of (V) and (e) are trimethylpropane (TMP), trimethylolethane (TME), glycerine, pentaerythritol, erythritol, threitol, dipentaerythritol, sorbitol, trimellitic anhydride, pyromellitic dianhydride, and dimethylolpropionic acid with TMP being most preferred, due to availability and effective results.
The amount of this branching agent (V) and (e) is preferably below 20 mol percent, more preferably below 10 mol percent, (including the range for (V) of 0.5 to 10), with a concentration of about 1 to 7 or 2 to 6 mol percent being most preferred. At very high amounts of branching agent the polyester is prone to gelation whereas at low amounts, such as below 0.5 and 0.1, the polyester has poorer performance and properties.
The dispersible linear polyester composition of (1) is blended with the branched water-dispersible polyester composition of (2) at temperatures greater than 200° C., preferably about 225° C., for at least one hour. In the adhesive blend composition according to the present invention the relative amounts of the two polyesters vary from about 20 to 80 weight percent of the polyester of (1) and about 20 to 80 weight percent of the polyester of (2). The concentration of these two polyesters in the hot melt adhesive composition according to the present invention is preferably greater than 30 but less than 80 weight percent polyester of (1) and greater than 20 but less than 70 weight percent of the polyester of (2). The concentration of the two polyesters is more preferably about 40 to 77 weight percent (1) and about 23 to 60 weight percent of (2), even more preferably about 60 to 75 weight percent of (1) and about 25 to 40 weight percent of (2) with a concentration of the two polyesters in weight percent of about 70 (1) and about 30 (2) being most preferred. Higher amounts of the polyester of (1) increase the melting point of the final adhesive composition. At amounts of the polyester of (1) higher that 80 weight percent, the adhesive has too high of a melting point to be practical. Higher amounts of the polyester of (2) decrease the melting point of the final adhesive. At amounts of the polyester of (2) higher that 80 weight percent, sometimes higher than 70, the adhesive has too low of a melting point to be practical.
The polyesters according to the present invention preferably have at least 50 weight percent of the linking groups linking the moieties of the monomeric units being ester linkages, more preferably at least 90 weight percent, with an ester linkage weight percent of 100 being most preferred.
The water-dispersible polyesters described herein have an inherent viscosity of at least 0.1 dL/g, preferably about 0.2 to 0.5 dL/g, measured in a 60/40 parts by weight solution of phenol/tetrachloroethane at 25° C. and at a concentration of about 0.25 g of polymer in 100 ml of solvent.
The final adhesive compositions preferably have a number average molecular weight of about 2,000 to 20,000 more preferably about 3,000 to 10,000. Although it is desirable to have as high a molecular weight as possible to achieve the maximum physical properties, such as tensile strength and peel strength, the melt viscosity also increase as molecular weight increases. Therefore, at very high molecular weights the melt viscosity is too high for many useful applications.
The preferred Tg of the adhesive composition according to the present invention is below 10° C. and more preferably varies from about 4° to -20° C., with a Tg of about 4° to -13° C. being most preferred. The Tg (glass transition temperature) of the adhesive compositions of the present invention are preferably as low as possible. Thus Tgs below 4° C. and even below 0° C. are preferred. Tgs of greater than 0° C. have generally higher ring and ball softening point (RBSP) and heat resistance but are not as flexible. A low Tg means that the adhesive compositions will not be brittle, thus, cartons adhered together with the adhesive compositions of the present invention when impacted, even at extremely cold temperatures will not shatter and thus maintain adhesion. However, extremely low Tgs are not easily obtained or at least not easily obtained without greatly affecting some other property, such as lowering the ring and ball softening point.
The hot melt adhesive composition according to the present invention preferably has a viscosity of about 1,500 to about 30,000 centipoise at 350° F. (177° C.), more preferably about 3,000 to 15,000 cP at 350° F. (177° C.) due to ease in application.
The ring and ball softening point (RBSP) of the adhesive composition of the present invention is preferably at least 80° C., more preferably 80° to 100° C. The high temperatures of RBSP are better since this means at higher storage temperatures delamination will not occur. (High RBSP provides delamination resistance).
The adhesive compositions according to the present invention are particularly useful due to their good combination of properties and are suitable for use as adhesives for many substrates including non woven assemblies (such as non woven polypropylene), paper products (such as paper and paperboard), and wood pulp and are easily recyclable and repulpable. The hot melt adhesives according to the present invention are recyclable/repulpable and improved over prior art repulpable hot melt adhesive compositions in that the set time, temperature sensitivity, compatibility, stability on storage, shear strength, tensile strength, viscosity, and cold flow resistance are improved.
The adhesive composition according to the present invention is applied to one substrate with a second substrate being placed on top of the adhesive forming an article having the adhesive laminated between two substrates.
The adhesive composition according to the present invention can be applied in liquid form in solvent or in an aqueous solution at a concentration of about 10 to 70 weight percent with the remainder being solvent or water or mixtures thereof. Surfactants and other additives can also be present to aid in the dispersibility of the adhesive composition. When applied as a solution, the adhesive compositions are generally applied by conventional processes, such as extrusion coating, spray coating, roll coating, brush coating, dip coating, etc.
The adhesive composition according to the present invention is preferably used as a hot melt adhesive. The hot melt adhesive composition is preferably applied in the melt at a temperature of about 150° to 200° C. to a surface of a substrate and, while remaining molten and pliable, applying a second surface of a substrate to the water-dispersible hot melt adhesive composition thereby forming an article of manufacture that comprises the water-dispersible hot melt adhesive composition laminated between two substrates or two surfaces of a substrate.
The adhesive compositions of the present invention are preferably not crosslinked since that would impair their water dispersibility and repulpability. However, they could be crosslinked, to a certain extent with diisocyanates to improve strength and heat resistance although this is less preferred.
The adhesive composition according to the present invention can also contain standard additives including stabilizers, preferably about 0.1 to about 0.5 weight percent stabilizers. Suitable stabilizers include the antioxidant type and generally consist of sterically hindered phenols, or sulfur or phosphorous substituted phenols. An especially useful antioxidant is Irganox 1010 (from Ciba-Geigy, Hawthorne, N.Y.) which is a pentaerythritol tetrakis-3(3,5-di-tertiarybutyl-4-hydroxyphenyl)propionate.
Additional additives can be added to raise and lower Tg and RBSP. These include, for example, elastomers, plasticizers, low molecular weight polyolefins, resins, and tackifiers. Although, elastomers can be added to the polyester composition, the presence of such elastomers may be adverse to certain desired properties of the composition. Therefore, it is preferable that the composition of the present invention contain substantially no elastomer. Additionally, the plasticizers such as DOP, DOTP, phenols, glycols, phthalate esters and the like that can be added, can distract from the heat resistance of the final composition lowering the RBSP.
Other additives such as UV light absorbers, nucleating agents, colorants, pigments, solvents, and fillers can be present in small amounts as needed and known in the adhesive art.
Tackifiers are added to the polyester composition to prevent cold flow and increase the softening point. Tackifiers are typically selected from at least one of the groups consisting of hydrocarbon resins, synthetic polyterpenes, functional copolymers, and rosin esters. Hydrocarbon resins are disclosed in U.S. Pat. No. 3,850,858 and functional copolymers, such as styrene-co-maleic anhydride, are well known in the art. Hydrocarbon resins, prepared according to U.S. Pat. No. 3,701,760, polyterpenes, and rosin esters can be used alone or in combinations. These tackifying resins, which preferably have softening points of at least 100° C. and most preferably 120° C., can be used in amounts of about 10% to 50% by weight of the adhesive composition, preferably about 25% to about 40% by weight. Suitable resins and rosin esters are the terpene polymers having a suitable ring and ball softening point such as the polymeric, resinous materials including the dimers as well as higher polymers obtained by polymerization and/or copolymerization of terpene hydrocarbons such as the alicyclic, monocyclic, and bicyclic monoterpenes and their mixtures, including allo-ocimene, carene, isomerized pinene, pinene, dipentene, terpinene, terpinolene, limonene, turpentine, a terpene cut of fraction, and various other terpenes. Commercially available resins of the terpene type include the Zonarez terpene B-series and 7000 series from Arizona Chemical. Also included are the rosin esters with acid numbers above 5 such as the Zonatac resins from Arizona Chemical. Particularly useful materials are terpene mixtures containing a mixture of sulphate terpene, and at least 20% of at least one other terpene selected from the group consisting of pinene, limonene, or dipentene.
These adhesive compositions can also be modified to increase the RBSP and reduce cold flow by including additives such as precipitated calcium carbonates and silicas such as fumed silica. A suitable fumed silica comes from Cabot Corp. as CABOSIL.
The present copolyester composition can be modified with random or alternating styrenic copolymers useful in the compositions of this invention and may be prepared by any of the several methods available for their synthesis. For example, the copolymers may be obtained by solution copolymerization directly from the respective monomers by the incremental additions of the more reactive monomer as taught by U.S. Pat. No. 2,971,939 or by a continuous recycle polymerization process described in U.S. Pat. Nos. 2,769,804 and 2,989,517. Suitable commercially available random or alternating copolymers include the "Dylark" styrene/maleic anhydride copolymers. Suitable blocked copolymers for example from Shell Chemical, include Kraton FG-1901X or Kraton FG-1921X linear styrene ethylene-1-butene styrene blocked copolymers. In formulating adhesives or sealants for use herein, the blocked copolymers should be used of 5-20%, preferably 7-12%.
Modified polyolefins suitable for use in the present invention are prepared by reacting a polyolefin with unsaturated polycarboxylic acid, anhydride or esters thereof, such as maleic anhydride. In formulating adhesive or sealants for use herein the modified polyolefins should be used in low amounts from 3-15% preferably 5-9%. These modified polyolefins can enhance heat resistance of the composition.
The adhesive composition of this invention can be prepared using one or more modifiers to the branched copolyester, by blending with the polyester at melt temperatures of 177°-200° C. and mixing until a homogeneous mixture is obtained. A cowles stirrer provides effective mixing for these preparations.
The following examples are intended to illustrate the present invention but are not intended to limit the reasonable scope thereof.
EXAMPLES
In the following examples GEL Permeation Chromatography (GPC) is used for determination of the molecular weight distribution averages: Mw, Mn, Mw/Mn (polydispersity), and Mz.
In the following examples the Peel Adhesion Failure Temperature was determined according to the following procedure to find the 180° peeling tension fail. This is determined by subjecting a specimen to a continuous dead weight loading of 100 grams per inch (2.54 cm) of bond width for 10 minutes at a given temperature.
The adhesive is laminated onto 30 pound (13.6 kg) kraft paper to a thickness of 1 mil (2.54×10 -3 cm) and a width of 1.5 inches (3.8 cm). Another section of kraft paper is placed on top of the adhesive laminate. The test specimen is heat sealed at 122° C. at 25 psi (0.17 kpa) for 0.2 seconds. Three specimens are prepared. The bonded peel specimens must condition overnight in a laboratory at 23° C. at 50% humidity before testing. The oven temperature is set at 14° C., the three specimens are placed therein, and a 100 gram weight is attached to each. The specimens are conditioned in the oven for 10 minutes, and the temperature is then raised 4° C. at 10 minute intervals. The Peel Adhesion Failure Temperature is the temperature in degrees C. at failure (3 test average).
Example 1
Preparation and Testing of Branched Polyester
Control:
A 1000 mL round bottom flask equipped with a ground-glass head, agitator shaft, nitrogen inlet, and a sidearm was charged with 139.4 grams (0.84 mole) of isophthalic acid, 23.4 grams (0.16 mole) adipic acid, 95.4 grams (0.90 mole) diethylene glycol, 31.2 grams (0.30 mole) neopentyl glycol, 6.7 grams (0.05 mole) trimethylol propane, 10.0 grams (0.01 mole) of poly(ethylene glycol), MW=1000, and 1.05 mL of a 1.46% (w/v) solution of titanium isopropoxide in n-butanol. The flask was purged with nitrogen and immersed in a Belmont metal bath at 200° C. for 90 minutes and 220° C. for an additional 90 minutes under a slow nitrogen sweep with sufficient agitation. After elevating the temperature to 280° C. a vacuum <=0.5 mm was installed 11 minutes to perform the polycondensation. The vacuum was then displaced with a nitrogen atmosphere and the polymer was allowed to cool after removing the flask from the metal bath. An inherent viscosity of 0.371 dL/g was determined for the recovered polymer according to ASTM D3835-79 and a glass transition temperature of 3° C. was obtained from thermal analysis by DSC. The polymer was clear and amorphous. Molecular weights as determined by GPC were: Mn=10,400, Mw=32,250, and Mz=104,150. The properties of this resin are illustrated in Table 1. This sample when placed in tap water, pH approximately equal to 8, was insoluble and would not be suitable for application as a repulpable adhesive.
Example 2
Preparation of Branched Water-Dispersible Polyester
A 1000 mL round bottom flask equipped with a ground-glass head, agitator shaft, nitrogen inlet, and a sidearm was charged with 192.0 grams (1.15 moles) of isophthalic acid, 35.1 grams (0.24 mole) adipic acid, 31.1 grams (0.105 mole) dimethyl-5-sodiosulfoisophthalate, 143.1 grams (1.35 mole) diethylene glycol, 46.8 grams (0.45 mole) neopentyl glycol, 10.05 grams (0.075 mole) trimethylol propane, 30.0 grams (0.03 mole) of poly(ethylene glycol), MW=1000, and 1.67 mL of a 1.46% (w/v) solution of titanium isopropoxide in n-butanol. The flask was purged with nitrogen and immersed in a Belmont metal bath at 200° C. for 90 minutes and 220° C. for an additional 90 minutes under a slow nitrogen sweep with sufficient agitation. After elevating the temperature to 280° C. a vacuum <=0.5 mm was installed for 15 minutes to perform the polycondensation. The vacuum was then displaced with a nitrogen atmosphere and the polymer was allowed to cool after removing the flask from the metal bath. An inherent viscosity of 0.258 dL/g was determined for the recovered polymer according to ASTM D3835-79 and a glass transition temperature of 9° C. was obtained from thermal analysis by DSC. The clear polymer was stabilized with 0.3 grams of Irganox 1010. Molecular weights as determined by GPC were: Mn=6,500, Mw=13,200, and Mz=20,800. The properties of this resin are illustrated in Table 1.
Example 3
Preparation of Branched Water-Dispersible Polyester
A 1000 mL round bottom flask equipped with a ground-glass head, agitator shaft, nitrogen inlet, and a sidearm was charged with 184.0 grams (0.92 moles) of dimethyl cyclohexanedicarboxylate, 23.7 grams (0.24 mole) dimethyl-5-sodiosulfoisophthalate, 95.4 grams (0.90 mole) diethylene glycol, 31.2 grams (0.30 mole) neopentyl glycol, 6.70 grams (0.05 mole) trimethylol propane, and 1.17 mL of a 1.46% (w/v) solution of titanium isopropoxide in n-butanol. The flask was purged with nitrogen and immersed in a Belmont metal bath at 200° C. for 90 minutes and 220° C. for an additional 90 minutes under a slow nitrogen sweep with sufficient agitation. After elevating the temperature to 280° C. a vacuum <=0.5 mm was installed for 10 minutes to perform the polycondensation. The vacuum was then displaced with a nitrogen atmosphere and the polymer was allowed to cool after removing the flask from the metal bath. An inherent viscosity of 0.210 dL/g was determined for the recovered polymer according to ASTM D3835-79 and a glass transition temperature of -4° C. was obtained from thermal analysis by DSC. The polymer was clear and nearly colorless. Molecular weights as determined by GPC were: Mn=5,800, Mw=10,400, and Mz=15,500. The properties of this resin are illustrated in Table 1.
Example 4
Preparation of Branched Water-Dispersible Polyester
A 1000 mL round bottom flask equipped with a ground-glass head, agitator shaft, nitrogen inlet, and a sidearm was charged with 128.0 grams (0.77 mole) of isophthalic acid, 23.4 grams (0.16 mole) adipic acid, 23.7 grams (0.08 mole) dimethyl-5-sodiosulfoisophthalate, 95.4 grams (0.90 mole) diethylene glycol, 31.2 grams (0.30 mole) neopentyl glycol, 6.70 grams (0.05 mole) trimethylol propane, 10.0 grams (0.01 mole) of poly(ethylene glycol), MW=1000, and 1.09 mL of a 1.46% (w/v) solution of titanium isopropoxide in n-butanol. The flask was purged with nitrogen and immersed in a Belmont metal bath at 200° C. for 90 minutes and 220° C. for an additional 90 minutes under a slow nitrogen sweep with sufficient agitation. After elevating the temperature to 280° C. a vacuum <=0.5 mm was installed for 10 minutes to perform the polycondensation. The vacuum was then displaced with a nitrogen atmosphere and the polymer was allowed to cool after removing the flask from the metal bath. An inherent viscosity of 0.226 dL/g was determined for the recovered polymer according to ASTM D3835-79 and a glass transition temperature of 13° C. was obtained from thermal analysis by DSC. The clear polymer was stabilized with 0.3 grams of Irganox 1010. Molecular weights as determined by GPC were: Mn=7,300, Mw=14,000, and Mz=22,600. The properties of this resin are illustrated in Table 1.
TABLE 1__________________________________________________________________________PROPERTIES OF ADHESIVE COMPOSITIONS(a) (b) (c) (d) (e) (f)ExampleSet Time Viscosity @ Tensile Strength Peel Adhesion Ring and BallNo., (sec) 177° C. cps (mpa) elongation % Failure Temperature °C. Tg °C. Softening Point__________________________________________________________________________ °C.1 7.0 4,120 -- 34 3 702 6.1 3,840 .09 > 1200% 35 9 823 4.2 3,570 .03-.09 > 1200% 30 -13 824 3.6 4,630 1.0, 873% 40 13 90 elongation__________________________________________________________________________ (a) TAPPI Symposium, Recyclable/Repulpable Hot Melts A Summary, June 1990, by Michael J. Ambrosini (b) ASTM D3236 Test Method (c) ASTM 412 Test Method (d) Kraft to kraft bond (e) ASTM D3418 (f) ASTM E28
Example 5
Repulpability Test (Neutral)*
Approximately 10 grams of each of the adhesives in Examples 2, 3 and 4 were melted, dyed, and coated onto white bond copier paper to a thickness of 1.5 to 3.0 mils (0.04 to 0.08 mm) with a wire wound rod. The coated paper was then cut to obtain a piece weighing 12 grams. The weighed coated paper was then torn into 1" by 1" (2.54 cm by 2.54 cm) pieces and placed into approximately 1000 mL of tap water in the bowl of a laboratory blender to obtain a solids to liquid consistency of ˜1.2% and soaked from 1 to 4 hours. The coated paper and water were agitated at 500 rpm for 10 minutes, at 1,000 rpm for 10 minutes, and 1,500 rpm for 10 minutes. Following agitation, a portion of the slurry was removed from the bowl and diluted to produce a 0.7% solids mixture. This mixture was stirred for 30 seconds and quickly poured into a Buchner funnel that contains a 100 mesh polyester screen. A vacuum pump was attached for a short interval until the water was evacuated from the funnel and a handsheet was formed. The handsheet and screen were then removed from the funnel and excess water was blotted away with Watman 5 filter paper. The handsheet was then weighted and dried on a warm hot plate. The dried handsheet was then inspected for "stickies" using both transmitted and reflected light.
All three examples were completely dispersible, in that during the hour soak in a room temperature neutral solution all dyed coating samples completely separated from copy paper. During agitation, the solution was foamy and a sweet odor was noticed. No adhesive residue (stickies) were on the hand sheet. Thus, there was complete repulpability. This test showed that the compositions in Examples 2, 3 and 4 were highly water dispersible and repulpable under neutral conditions.
Example 6
Repulpability in alkaline solution*
An alkaline solution was prepared by adding 6.2 g of NaOH pellets, 3 g of tetrasodium pyrophosphate (TSPP) and 0.6 ml of Triton x-100 surfactant to 400 ml of H 2 O at room temperature. The solution was warmed on a hot plate to 27° C. When the TSPP had dissolved, it was diluted to 1000 ml and adjusted to a pH of 9-12 with H 2 O or base. The solution was then brought to 85° C. and then 1"×1" (2.54×2.54 cm) pieces of coated paper from Examples 2, 3 and 4 prepared as in Example 5 were added as the solution was slowly stirred at the blend station. When coated paper began to de-fiber, the mixer speed was adjusted to give a gentle rolling of slurry. Mixing was continued for 15-30 minutes. After defibering for 15-30 minutes, slurry was diluted to 1000 ml and stirred thoroughly to assure a uniform suspension. The handsheet was formed as in Example 5. The degree of adhesive repulpability was evaluated as in Example 5.
All three examples were completely dispersible, in that dyed coating sample began separating from the copy paper within 5 minutes of entering the heated (85° C.) alkaline solution. During the 30 minute agitation the coating completely dispersed throughout solution. There was a pale orange color visible in handsheet; however, no adhesive residue (stickies) was on hand sheet. Thus, there was complete repulpability. The results indicate that Examples 2, 3 and 4 are repulpable under alkaline conditions.
Example 7
Dispersibility of Adhesive Coated Wood Pulp
Wood pulp (5 grams) taken from a Huggies brand diaper from Kimberly Clark, was coated with 1.5 grams of the adhesive from Examples 2, 3 and 4 at 350° F. (177° C.). The adhesive coated wood pulp was placed in one liter of tap water (pH 7.9) at room temperature for one hour with hand stirring approximately every 10 minutes. The slurry was poured through a 600 mL Hirsch funnel pulled under vacuum at 25 psi until water is completely removed out of the funnel. The wood pulp remained in the funnel without any sign of adhesive present in the funnel. All of the adhesive passed through the funnel into the container with the water.
Example 8
Solubility of Examples 2, 3, and 4
A one gram sample of each polyester from Examples 2, 3, and 4 was placed in tap water (pH 8.0), deionized water (pH 7.2) and two simulated body fluids. The first simulated body fluid containing 10 gms. sodium chloride, 4 gms. ammonium carbonate, 1 gm disodium hydrogen phosphate, and 0.25 grams histidine monohydrochloride, dissolved in 1 liter of deionized water, with a final pH 8.0. The second simulated body fluid containing 10 grams sodium chloride, 1 gram lactic acid, and 1 gram disodium hydrogen phosphate, and 0.25 gram histidine monohydrogenchloride, dissolved in 1 liter deionized water, with a final pH of 3.9.
Test Results
Examples 2, 3, and 4 dissolved in less than one hour immersion in tap water and deionized water and remained insoluble in simulated body fluid solution after 24 hours immersion.
The following examples 1B through 9B are examples of the adhesive composition according to the present invention that is a blend of two polyesters. These examples were tested according to the test used in the prior examples except for Gel Permeation Chromatography (GPC) which used a polystyrene standard.
GPC is used for determination of the molecular weight distribution averages: Mw, Mn, Mw/Mn (polydispersity), and Mz. Approximately 60 milligrams of sample is weighed and dissolved in 20 ml. of tetrahydrofuran (THF) containing toluene (internal std.) at a level of 0.3% (v/v). The sample is filtered (if necessary) and then run on the GPC system. The data system generates a report showing: (1x) the molecular weight distribution averages, (2x) a time slice report, and (3x) standard, purchased from Polymer Laboratories, covering a molecular weight range of 580 to 1,030,000. The mode of calibration is "Narrow MW Standard Peak Positions".
Example 1B
Preparation of Linear Water-Dispersible Polyester Composition 1
A 500-mL, round bottom flask equipped with a ground-glass head, an agitator shaft, nitrogen inlet, and a sidearm was charged with 73.87 g (0.445 mol) of isophthalic acid, 14.74 g (0.055 mol) of 5-sodiosulfoisophthalic acid, 81 g (0.75 mol) of diethylene glycol, 0.19 grams of titanium tetraisopropoxide and 0.847 g (0.0055 mol) of sodium acetate tetrahydrate. The flask was immersed in a Belmont bath at 200° C. for two hours under a nitrogen sweep. Heating was stopped and the copolyester was removed from the flask. The polymer had an inherent viscosity of 0.45 dL/g according to ASTM D3835-79 and a glass transition temperature of 29° C. as measured by differential scanning colorimetry (DSC) analysis. The polymer which was transparent and amorphous was extruded and pelletized. The polymer had a weight average molecular weight (Mw) of 8,924 and a number average molecular weight (Mn) of 5,422 by GPC using a polystyrene standard.
Example 2B
Preparation of Branched Water-Dispersible Polyester Composition 2
To a three-neck round-bottom flask equipped with a mechanical stirrer, a stream partial condenser a Dean-Stark trap, and a water condenser were charged the following reactants: neopentyl glycol (363.38 g, 3.49 m), 5-sodiosulfoisophthalic acid (29.30 g, 0.109 m) and the catalyst, Fascat 4100 (Atochem North America, Inc.) (0.56 g). The mixture was heated to 150° C. and stirred under N 2 atmosphere and the temperature then gradually increased to 220° C. and the distillate (water) was collected in the Dean-Stark trap until the mixture was clear (about 1 hr). The acid number was determined to be close to zero, and the mixture was cooled to 150° C. The second stage reactants, trimethylolpropane (75.4 g, 0.563 m), isophthalic acid (329.01 g, 1.98 m) and adipic acid (202.25 g, 1.38 m) were then added. The temperature was gradually raised to 220° C. and the reaction continued for four more hours to yield a resin with an acid number of 3.6. The polymer had a weight average molecular weight (Mw) of 6,241, a number average molecular weight (Mn) of 1,740 and a polydispersity index of 3.6, determined by GPC using a polystyrene standard.
Example 3B
Preparation of a Water-Dispersible Hot-Melt Adhesive
A blend of the linear water-dispersible polyester polymer 1 prepared as in Example 1B (70 parts) by weight and the branched water-dispersible polyester polymer 2 of Example 2B (30 parts) by weight was prepared by combining the two polymers and stirring at about 225° C. for 2 hours to produce the adhesive composition. The composition had a Tg of about 11° C., a weight average molecular weight of 5,410, a number average molecular weight of 1,554, and a viscosity of 19,450 centipoise at 350° F. (175° C.) as determined on a Brookfield HV: II Viscometer. The adhesive had a fast set time, as determined by a standard procedure (TAPPI Symposium, Recyclable/Repulpable Hot Melts--A Summary--U.S.A. and Europe, June, 1990, by Michael J. Ambrosini) on a corrugated kraftboard substrate, good lap sheer strength (ASTM D1002 Test Method) and good tensile strength (ASTM 412 Test Method). The results are reported in Table 2. Into 100 ml of hot water (65°-80° C.) at a pH of 7.8, were mixed 0.5 grams of adhesive chips. Within 15 minutes under mild agitation the adhesive was completely dispersed in the water, forming a milky mixture. Repulpability results are in Tables 3 and 4.
Example 4B
An adhesive composition was prepared by blending 60 parts by weight of the linear water-dispersible polymer prepared as in Example 1B with 40 parts by weight of the branched water-dispersible polyester of Example 2B and the properties of the polymer and the polymer and adhesive properties determined as in Example 3B above. The adhesive properties are reported in Table 2. The adhesive chips were dispersed in hot water as in Example 3B within 15 minutes. The adhesive had good repulping properties (see Tables 2 and 3), a Tg of about 8.4° C. a weight average molecular weight of 5,272, a number average molecular weight of 1,563 and a viscosity of 17,400 centipoise at 350° F. (175° C.).
Example 5B
An adhesive composition was prepared by blending 40 parts by weight of the linear water-dispersible polymer prepared as in Example 1B with 60 parts by weight of the branched water-dispersible polyester of Example 2B and the properties of the adhesive composition determined as in Example 3B. The adhesive properties are reported in Table 2. The adhesive chips were dispersed in hot water as in Example 3B within 15 minutes. The adhesive had good repulping properties (see Tables 3 and 4), a Tg of 4.2° C. a weight average molecular weight of 7,622, a number average molecular weight of 1,715 and a viscosity of 2,500 centipoise at 350° F. (175° C.).
Example 6B
An adhesive composition was prepared by blending 30 parts by weight of the linear water-dispersible polyester prepared as in Example 1B with 70 parts by weight of the branched water-dispersible polyester of Example 2B and the properties of the adhesive composition determined as in Example 3B. The adhesive properties are reported in Table 2. The adhesive chips were attempted to be dispersed in hot water as in Example 3B, however, only partial dispersion occurred. The adhesive had marginal repulping properties (see Tables 3 and 4), a Tg of 4.4° C., a weight average molecular weight of 7,316, a number average molecular weight of 1,831 and a viscosity of 2,490 centipoise at 350° F.
TABLE 2______________________________________PROPERTIES OF ADHESIVE COMPOSITIONS (a) (b) (c) (d) Set Lap Tensile Peel AdhesionExample Time Shear Strength FailureNo. (sec) (mpa) (mpa) Temperature °C.______________________________________3B 1.7 8.6 2.9 434B 1.4 1.3 1.4 435B 1.8 4.3 .3 306B 3.6 4.3 .1 --______________________________________ (a) TAPPI Symposium, Recyclable/Repulpable Hot Melts A Summary, June 1990, by Michael J. Ambrosini (b) ASTM D1002 Test Method (c) ASTM 412 Test Method (d) Kraft to kraft bond
Example 7B
Repulpability Test (Neutral)
Approximately 10 grams of each of the adhesives in Examples 3B, 4B, 5B, and 6B were melted, dyed, and coated onto white bond copier paper to a thickness of 1.5 to 3.0 mils (0.04 to 0.08 mm) with a wire wound rod. The coated paper was then cut to obtain a piece weighing 12 grams. The weighed coated paper was then torn into 1" by 1" (2.54 cm by 2.54 cm) pieces and placed into approximately 1000 mL of tap water in the bowl of a laboratory blender to obtain a solids to liquid consistency of ˜1.2% and soaked from 1 to 4 hours. The coated paper and water were agitated at 500 rpm for 10 minutes, at 1,000 rpm for 10 minutes, and 1,500 rpm for 10 minutes. Following agitation, a portion of the slurry was removed from the bowl and diluted to produce a 0.7% solids mixture. This mixture was stirred for 30 seconds and quickly poured into a Buchner funnel that contains a 100 mesh polyester screen. A vacuum pump was attached for a short interval until the water was evacuated from the funnel and a handsheet was formed. The handsheet and screen were then removed from the funnel and excess water was blotted away with Watman 5 filter paper. The handsheet was then weighted and dried on a warm hot plate. The dried handsheet was then inspected for "stickies" using both transmitted and reflected light. The repulpability properties are reported in Table 3. This test showed that the adhesive of Example 3B is the most highly water-dispersible.
TABLE 3*__________________________________________________________________________Repulp Evaluations Unconditional (Neutral)EXAMPLE 3B EXAMPLE EXAMPLE EXAMPLE 6BCompletely 4B 5B Not/Very SlightlyDispersible Partial Partial Dispersible__________________________________________________________________________Dispersion of Material began to Polymer began to No dispersion ofmaterial began disperse from disperse from polymer from paperimmediately upon paper after 2 paper immediately was seen duringexposure of coated minutes in water. on exposure to soaking period ofpaper to water, Material was off water. Nearly 1 hr.producing a milky the paper and into complete disper- HANDSHEETsolution. milky solution sion after 20 Gummy residue noticedAppeared to be after 30 minutes minutes soaking. in pulper after agitation.completely in water. Ring of Formed milky Handsheet had stickydispersed after 15 dispersed material solution during areas of polymer throughout.minutes of soaking noticed at bottom soaking. Difficult to removein water with NO of soaking beaker HANDSHEET handsheet from filterAGITATION. after 1 hr. Gummy residue screen after handsheetHANDSHEET HANDSHEET noticed in pulper formed. Some stickyVery little Gummy residue after agitation. polymer remained on screen.evidence of noticed in pulping Undispersedadhesive remaining vessel following polymer andin handsheet. agitation. Some undefibered paper visible adhesive were noticed in specks noticed in handsheet handsheet.__________________________________________________________________________ *Tappi, 1993, Hot Melt Symposium Procedure, Barrett
Example 8B
Repulpability in alkaline solution
An alkaline solution was prepared by adding 6.2 g of NaOH pellets, 3 g of tetrasodium pyrophosphate (TSPP) and 0.6 ml of Triton x-100 surfactant to 400 ml of H 2 O at room temperature. The solution was warmed on a hot plate to 27° C. When the TSPP had dissolved, it was diluted to 1000 ml and adjusted to a pH of 9-12 with H 2 O or base. The solution was then brought to 85° C. and then 1"×1" (2.54×2.54 cm) pieces of coated paper prepared as in Example 7B were added as the solution was slowly stirred at the blend station. When coated paper began to defiber, the mixer speed was adjusted to give a gentle rolling of slurry. Mixing was continued for 15-30 minutes. After defibering for 15-30 minutes, slurry was diluted to 1000 ml and stirred thoroughly to assure a uniform suspension. The handsheet was formed as in Example 7B. The degree of adhesive repulpability was evaluated as in Example 7B. The results are reported in Table 4.
TABLE 4*__________________________________________________________________________Repulp Evaluations Alkaline (pH = 10.6)EXAMPLE 3B EXAMPLE 4B EXAMPLE 5B EXAMPLE 6BCompletely Dispersible Complete Dispersion Partial Partial__________________________________________________________________________Dispersion began Dispersion began Gummy residue Some dispersionimmediately upon immediately on noticed in pulper before agitation.exposure to alkaline exposure of coated following agitation Thick "pudding like"solution. Final paper to alkaline AND on filtration residue producedhandsheet appeared solution. No screen after during alkalinefree of dye and adhesive apparent in formation of agitation. Driedadhesive. handsheet. handsheet. "circles" of residue were seen on filter side of handsheet. Handsheet difficult to remove from filter screen.__________________________________________________________________________ *Tappi, 1993, Hot Melt Symposium Procedure, Barrett
The above results show that adhesive prepared in Example 3B is best followed by Example 4B. Although the adhesive from Examples 5B and 6B were only partially repulped in alkaline solution, this is significantly improved over conventional hot melt adhesives.
Example 9B
Dispersibility of Adhesive Coated Wood Pulp
Wood pulp (5 grams) taken from a Huggies brand diaper from Kimberly Clark, was coated with 1.5 grams of the adhesive from Example 5B at 350° F. (177° C.). The adhesive coated wood pulp was placed in one liter of tap water (pH 7.9) at room temperature for one hour with hand stirring approximately every 10 minutes. The slurry was poured through a 600 mL Hirsch funnel pulled under vacuum at 25 psi until water is completely removed out of the funnel. The wood pulp remained in the funnel without any sign of adhesive present in the funnel. All of the adhesive passed through the funnel into the container with the water. | Disclosed is a water-dissipatable or dispersible adhesive composition that is useful in forming paper articles and other products that can be recycled through repulping in both neutral and alkaline media. The water-dispersible adhesive composition is preferably a hot melt adhesive that is a low molecular weight, branched copolyester containing a sulfomonomer. Additional utility for the invention resides in the manufacture of recyclable articles where insolubility in body fluids combined with solubility in tap water are required. | 2 |
CROSS-REFERENCE
The present application claims the benefit of U.S. Provisional Patent Application No. 61/693,635 filed on Aug. 27, 2012, and the benefit of U.S. Provisional Patent Application No. 61/694,062, filed on Aug. 28, 2012, both of which are hereby incorporated by reference in their entirety.
FIELD OF THE INVENTION
The present invention generally relates to power tools, and more particularly, but not exclusively, to a housing construction for an electrically driven power tool.
BACKGROUND OF THE INVENTION
Hand-held power tool housing construction remains an area of interest. Many current electrically driven power tool housings fail to provide adequate strength. Some current designs provide for a one-piece tubular housing to bolster strength; however, this design may not lend itself well to battery powered tools due to various complexities involved in assembling the electronic components therein. Therefore, further technological developments are desirable in this area.
BRIEF SUMMARY OF THE INVENTION
One embodiment of the present invention is a housing construction for a power tool. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for providing a unique housing for an electrically driven power tool that includes a split housing, a substructure, and a reinforcing superstructure. Further embodiments, forms, features, aspects, benefits, and advantages of the present application shall become apparent from the description and figures provided herewith.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The description herein makes reference to the accompanying figures wherein like reference numerals refer to like parts throughout the several views, and wherein:
FIG. 1A is an exploded perspective view of one embodiment of a power tool housing.
FIG. 1B is an exploded view of one form of a gear assembly.
FIG. 2 is a cross sectional view of one embodiment of power tool housing.
FIG. 3 is a cross sectional view of yet another embodiment of a power tool housing.
DETAILED DESCRIPTION OF THE INVENTION
For purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
FIG. 1A illustrates one embodiment of a power tool assembly 100 . The power tool assembly 100 includes a tool housing 130 , a substructure 104 , a gear assembly 106 , a superstructure 108 , and a tool head 112 . The tool housing 130 , substructure 104 , and superstructure 108 include a variety of unique features to strengthen the power tool assembly 100 .
The tool housing 130 can be divided into two portions, for example, a first half 116 and a second half 118 as shown. The first and second halves 116 , 118 can be coupled to form the tool housing 130 . In one form, the first and second halves 116 , 118 are joined in a manner such that a clamshell style tool housing 130 is formed. The tool housing 130 can be constructed from a variety of materials including various composites, polymers, or any other material suitable for the construction of the tool housing 130 , which can be determined based upon for example a force to be applied to the tool housing 130 .
In the illustrated embodiment, a plurality of ribs 114 a extend from an inner surface of the tool housing 130 . As shown, the first half 116 and the second half 118 can each include a plurality of radially inwardly extending ribs 114 a and recessed grooves 114 b . The radially inwardly extending ribs 114 a need not encircle the full interior of the tool housing 130 . The substructure 104 includes a plurality of ribs and grooves 120 a , 120 b respectively that are sized to receive the ribs and grooves 114 a , 114 b extending from the inner surface of the tool housing 130 . In some forms, the substructure 104 can additionally and/or alternatively include a plurality of ribs 120 a which interlock between the plurality of ribs 114 a extending from the inner surface of the tool housing 130 . When the first and second halves 116 , 118 of the tool housing 130 are assembled together, the ribs 114 a of the tool housing 130 mate with the grooves 120 b of substructure 104 to prevent or resist relative axial movement between the tool housing 130 and the substructure 104 . It is contemplated that the substructure 104 and the tool housing 130 can be configured to mate in a variety of fashions, through protrusions received in grooves, through an extension disposed in a channel, or any other type of configuration such that the tool housing 130 and the substructure 104 interlock to resist axial movement relative to each other.
The substructure 104 receives at least a portion of the motor 102 in an inner cavity of the substructure 104 . The substructure 104 can be substantially tubular in shape; however, any shape may be utilized such that the substructure 104 can mate with the tool housing 130 and can at least partially house the motor 102 . In one form, the substructure 104 can fully encompass the motor 102 . The substructure 104 can be constructed of various metals, such as steel or the like, and can be constructed through various processes, including, but not limited to casting or progressive die forming. In one form, the substructure 104 is constructed of one or more materials that are stronger than the materials from which the tool housing 130 is constructed.
The motor 102 is an electrically powered motor. The motor 102 can take any configuration such that the motor 102 converts electrical energy into mechanical energy. This mechanical energy can be transferred through a gear assembly 106 , and other assemblies, to drive a tool head 112 . The motor 102 can be at least partially retained by a motor retainer 132 or the like. The motor retainer 132 can aid in the prevention of rotation of the motor 102 relative the substructure 104 .
The motor 102 can be in electrical communication with a battery pack 124 through a wiring harness and motor controller 126 . The battery pack 124 can be semi-permanently affixed to the power tool assembly 100 such that the entire power tool assembly is placed in a charger or has a charger coupled thereto, or the battery pack 124 can be removable from the power tool assembly 100 to allow for quick battery changes and charging at a remote charging station.
Referring more closely to FIGS. 1A and 1B , a motor 102 output can be placed in mechanical connection with a gear assembly 106 comprising a plurality of gears 138 . In one form, a ring gear stop 134 resists axial movement of a ring gear housing 136 and therefore axial movement of the gear assembly 106 . While the mechanical connection between the motor 102 output and the tool head 112 has been illustrated in the form of a ring gear housing 136 including a gear assembly 106 , the application is not intended to be limited thereto. It is contemplated that any mechanical connection, including a direct connection, may be utilized to transfer power from the electric motor 102 to the tool head 112 .
The tool head 112 provides an output for a tool bit, socket, or the like. The tool head 112 is illustrated as a ratchet in FIG. 1A . The tool head 112 can be utilized to tighten and loosen a variety of threaded fasteners, such as nuts, bolt heads, or the like. The tool head 112 can be coupled to the power tool assembly in a variety of manners, such as through a tool head fastener 142 .
The tool assembly 100 can be operated in both a powered mode and in a manually-operated mode. In a powered mode, an operator holds a tool grip 128 while the tool head 112 delivers torque to a fastener, using the mechanical power that the electric motor 102 has delivered. In the manually-operated mode, the operator manipulates the tool grip 128 like a socket wrench, applying force to the handle, and using the power tool assembly 100 as a moment arm for creating and delivering torque to the fastener. In some forms, various motor 102 and gearing 106 configurations can be utilized to switch between the manual and powered mode.
The superstructure 108 and the tool housing 130 include respective tapers 210 and 212 . The taper 210 of the superstructure 108 applies a force against the taper 212 of the tool housing 130 to retain the first and second housing portions 116 , 118 together and to resist or prevent movement of the tool housing 130 relative to the substructure 104 . As described in greater detail below, a suitable nut 110 can be used to compress the taper 210 of the superstructure 108 against the taper 212 of the tool housing 130 . FIG. 2 shows one example of the taper 212 of the tool housing 130 in relation to the taper 210 of the superstructure 108 . The taper 210 of the superstructure 108 can take any form such that it is operable to apply a radially inward force to the taper 212 of the tool housing 130 . The superstructure 108 can include a clamp ring, a snap ring, or any other structure that includes a taper 210 that is suitable to exert a radially inward force on a taper 212 of the tool housing 130 . The superstructure 108 can be constructed of various materials, including metals such as aluminum or steel, that exhibit a greater material strength than a material strength of the tool housing 130 . In a specific form, the superstructure 108 can be formed through a casting process, such as die casting.
In the illustrated embodiment, the substructure 104 has a threaded projecting portion 214 . The nut 110 has corresponding threads 240 and can be fastened to the substructure projecting portion 214 such that, when tightened, the nut 110 exerts an axial force upon the superstructure 108 . The taper 210 of the superstructure 108 , in turn, exerts an axial and radial force upon the taper 212 of the tool housing 130 . The radial force on the tool housing 130 radially clamps, that is compresses, the first and second halves 116 , 118 of the tool housing 130 together, preventing or resisting the first and second halves 116 , 118 from coming apart. In one form, where mating ribs/grooves 114 a , 114 b and ribs/grooves 120 a , 120 b respectively are present, the axial force on the tool housing 130 is transmitted to the ribs/grooves 114 a , 114 b to axially urge the ribs/grooves 114 a , 114 b against the ribs/grooves 120 a , 120 b with which they mate to prevent or resist axial movement of the tool housing 130 relative to the substructure 104 .
Referring again to FIG. 2 , in one form a ring gear stop 202 is attached to the substructure 104 . The ring gear stop 202 can be connected to the substructure 104 such as through a weld 204 or the like. The ring gear housing 136 can include a plurality of outer threads 208 which are received by a plurality of inner threads 218 of the substructure 104 . The ring gear housing 136 can be threaded such that it abuts the ring gear stop 202 .
Referring now to FIG. 3 , in some forms, the tool head fastener 142 can be directly fastened to the tool substructure 104 such as through tool head fastener threads 312 . In this form, the ring gear housing 136 is placed in an abutting relationship 312 with the substructure 104 . Additionally, various portions 302 can be formed integrally with the substructure 104 rather than being welded or attached, as was described with reference to FIG. 2 . Although specific illustrative examples have been given, as was previously aforementioned, it is contemplated that the tool head 112 is mechanically interconnected to the electric motor 102 in any suitable manner such that the electric motor 102 can transfer power to the tool head 112 .
The electric motor 102 can generate heat during use. To evacuate this heat, exhaust vents 308 can be disposed in the motor 102 . A vent 310 can additionally be located in the substructure 104 and a vent 306 can be located in the tool housing 130 allowing heated air 304 to exit from the motor 102 . As is illustrated, the vents 308 , 310 , 306 can be axially and radially aligned such that air can flow directly radially outward. In some forms, this will allow a user to view the vent 308 of the motor 102 through the vent 306 in the tool housing 130 . In further forms, multiple flowpaths can be disposed in the motor 102 , the tool housing 130 , and the substructure 104 to provide for both an inlet air flow and an exhaust air flow. For example, the tool housing 130 can include a first flowpath in fluid communication with a second flowpath located in the motor 102 , and the second flowpath can be in fluid communication with the intake and or the exhaust of the motor 102 . The first flowpath can be at least partially radially aligned with the second flowpath, and the second flowpath can be at least partially radially aligned with the intake and/or exhaust of the motor 102 . Any number of airflow paths are contemplated to provide cooling to the motor 102 .
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment(s), but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as permitted under the law. Furthermore it should be understood that while the use of the word preferable, preferably, or preferred in the description above indicates that feature so described may be more desirable, it nonetheless may not be necessary and any embodiment lacking the same may be contemplated as within the scope of the invention, that scope being defined by the claims that follow. In reading the claims it is intended that when words such as “a,” “an,” “at least one” and “at least a portion” are used, there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. Further, when the language “at least a portion” and/or “a portion” is used the item may include a portion and/or the entire item unless specifically stated to the contrary. | An apparatus is disclosed including a motor housing structured to receive at least a portion of an electric motor, a tool housing including a first half and a second half, wherein the tool housing defines an end taper, a tool attachment in mechanical communication with the electric motor, and a retention member including an inner taper structured to interface with the end taper of the tool housing to resist relative motion between the tool housing and the motor housing. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application is a divisional patent application, and incorporates by reference, U.S. patent application Ser. No. 11/609,972 filed on Dec. 13, 2006 entitled “Method for Repairing an Electrode Assembly”.
FIELD OF THE INVENTION
[0002] The present invention relates to methods to repair used electrode assemblies in acoustic shock wave generating devices such as lithotripters.
BACKGROUND OF THE INVENTION
[0003] Acoustic shock waves are created when a high voltage discharge spark passes between two coaxially aligned opposing electrode tips. In the presence of a fluid the energy is released by the spark which flashes the water to steam creating an acoustic wave wherein a series of such waves can pass through tissue to break up concrements within the body.
[0004] Preferably, the fluid around the electrode tips is a saline solution to enhance electro conductivity. In some electrode assemblies the fluid surrounding the tips is also charged with carbide particles to further increase conductivity. Such a device is described in U.S. Pat. No. 6,113,560 entitled “Method and Device For Generating Shock Waves For Medical Therapy, Particularly For Electro-Hydraulic Lithotripsy” issued Sep. 5, 2000.
[0005] As can easily be appreciated the spark generated by the voltage discharge can create a large amount of heat which tends to burn the tips of the opposing electrode conductors. As the tips burn, the spark gap distance increases resulting in even higher voltages to create a discharge. At some point this dramatically degrades the shock wave pulses generated rendering the electrode assembly non effective. This situation can occur in a very quick time meaning the replacement of the electrode assemblies is done after every second, third or fourth patient procedure. While these devices are adapted for rapid change over or replacement it is also noted that each assembly can cost as much as several hundred dollars.
[0006] Accordingly, the device described in U.S. Pat. No. 6,113,560 has been touted as having a longer time of useful capacity and better gap distance maintenance than other similar devices. While this is true, the replacement cost is offset by the high end price demanded for the product.
[0007] In U.S. Pat. No. 6,849,994 granted Feb. 1, 2005 in a patent entitled “Electrode Assembly for Lithotripters” the same owner of the U.S. Pat. No. 6,113,560 patent describes the need for refurbishing electrode assemblies used in lithotripters by providing easily replaceable tips. In that patent the inventors noted that a prior art electrode with an insulating layer required the insulating layer to be machined off the inner conductor prior to replacement of the discharge tip and then reapplication of the insulating layer, presumably by remolding the plastic insulating layer over the inner conductor. Naturally this was a labor intensive practice that was cost prohibitive. It was their idea to provide threaded replacement tips that could easily been replaced when burnt to refurbish a used electrode assembly. This, they argued, could greatly reduce replacement cost.
[0008] The present inventive method has found a simple quick and very precise method to repair those electrode assemblies without removable tips that were believed to be too costly to repair. No grinding or machining of the insulator layer was required.
[0009] The number of such used devices is extremely large and therefore an efficient repair process would be invaluable to the physicians using such a lithotripter having those types of electrode assemblies.
[0010] The following description and drawings provide a novel way in which repair of such devices is not only feasible but highly efficient.
SUMMARY OF THE INVENTION
[0011] A method of repairing a used electrode device is disclosed wherein the method has the steps of providing a used electrode assembly having an inner conductor with an integral electrode tip encapsulated in an insulator body having an outer conductor and an outer electrode tip; and pressing the inner conductor with integral electrode tip while holding or restraining the insulator body to apply an force sufficient to overcome at least partially the adhesion forces at the mating surfaces of the inner conductor and the insulator body. Thereafter by grasping an end of the inner conductor opposite the tip while holding the insulator body and withdrawing the inner conductor from the insulator body the parts can be separated. Then by measuring the amount the inner electrode tip has been burnt as compared to a new tapered tip to establish a cut distance ΔX; and recutting the tip by machining the burnt portion along the tip taper surface toward and into a shoulder of the inner conductor by a distance equal to the cut distance ΔX the electrode tip can be reshaped.
[0012] The inner conductor further has a shoulder taper surface extending from an end adjacent a base of the integral electrode tip; and the method further includes the step of recutting the shoulder taper shoulder by machining the outside diameter of the inner conductor at a distance ΔX beyond the intersection of the shoulder taper surface and the diameter of the conductor along the same angle to form a conical surface of the same diametrical dimensions as the original shoulder surface.
[0013] In one embodiment the method further includes cutting a pair of legs of the burnt outer electrode at a distance D extending outwardly from the insulator housing to leave two protruding leg portions; placing the insulator body with two protruding leg portions in a half of a split fixture, wherein the slip fixture has two halves each with an interior surface molded or otherwise shaped to replicate the exterior surface of the insulator body; placing an outer electrode with two legs into the fixture wherein the two legs overlap the pair of cut leg portions embedded in the insulator body; setting the distance of the overlap to replicate the proper gap distance; closing the fixture securing the outer electrode against the projecting legs; introducing a pair of welding tips through holes in the fixture exposing the overlapping leg portions; and pressing the welding tip against the legs and welding a leg of the outer tip to the projecting leg portion. This method may also include slipping a pair of insulator tubes over the legs and moving the insulators to a central portion of the electrode prior to placing in the fixture and welding the legs; and moving an insulator over each welded leg portion after welding. Thereafter by re-inserting a recut of an inner conductor into an insulator body and pressing the conductor until fully seated in the insulator body to form an assembly.
[0014] This repaired used electrode assembly prior to repairing has an outer sleeve attached to the insulator body, the sleeve being filled with a particle suspended fluid and the sleeve being retained by a metal ring at the location of attachment to the insulator body and prior to the step of removing the inner conductor from the insulator body the method further may require placing the electrode assembly in a fixture with a collet holding the metal ring tin place; pushing on the sleeve to release the ring; and removing the assembly from the fixture and separating the sleeve from the insulator body. Thereafter the step of emptying the fluid into a container while filtering the suspended particles may be used along with the steps of removing a particle holding container from the sleeve; opening the container; recharging the container with particles; and closing the refilled container and reinserting into the sleeve, the sleeve has two vent holes that can be sealed by sealing the vent holes with a tape labeled “remove prior to use”; filling the sleeve with saline solution; placing the metal ring around the sleeve; placing the repaired electrode assembly into the filled sleeve and pressing the metal ring over the sleeve and insulator body joint to tightly seal the assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The invention will be described by way of example and with reference to the accompanying drawings in which:
[0016] FIGS. 1A , 1 B, 1 C are views of the electrode assembly.
[0017] FIG. 1A is a perspective view of an assembled electrode.
[0018] FIG. 1B is a cross sectional view of the assembled electrode of FIG. 1A .
[0019] FIG. 1C is an exploded perspective view of the various components of the electrode assembly of FIG. 1A .
[0020] FIG. 2 is a view of an assembly fixture showing how the metal retaining ring is dislodged from the plastic sleeve.
[0021] FIG. 2A is an enlarged view of the retaining ring being dislodged.
[0022] FIG. 3A is a view of the assembly fixture with the plastic sleeve removed placed in a holding fixture and an arbor press for dislodging the insulator body grip on the inner conductor.
[0023] FIG. 3B shows the removal of the inner conductor from the insulator body.
[0024] FIG. 4 is a cross sectional view of the inner conductor with integral electrode 3 being measured.
[0025] FIG. 5 is a view of a measuring device showing how the burnt tip can be measured.
[0026] FIG. 6 is a lathe used on the inner conductor so it can be polished and recut to reform the inner electrode tip.
[0027] FIG. 7A is a perspective view showing the fixture for holding the outer electrode piece and the insulator body with two cut legs in alignment prior to welding.
[0028] FIG. 7B shows the fixture closed holding the components and the welding tips prior to being positioned through openings in the fixture welding the electrode legs together.
[0029] FIG. 7C shows the welding tips positioned through the openings in the fixture to make the weld.
[0030] FIG. 8 shows the reassembly of the inner conductor to the insulator housing body.
[0031] FIG. 9A shows the sleeve having tape placed over the gas vent holes.
[0032] FIG. 9B shows the reassembled electrode.
DETAILED DESCRIPTION OF THE INVENTION
[0033] With reference to FIGS. 1A , 1 B, 1 C an electrode assembly 1 is shown having two electrodes 3 , 4 . The electrode 3 is connected to an inner conductor 9 embedded in a plastic installation body 8 that has been insert molded around an electrical conductor 9 . The electrode 4 is electrically connected to a tubular outer conductor 10 . The outer electrode 4 has a pair of legs 4 A and 4 B connected by a transverse tip portion 4 C which has the electrode projecting toward the electrode tip 3 . When new this distance is set at a spark gap distance S. The space around the electrodes 3 , 4 is surrounded by a sleeve 11 which is permeable to shock waves and has two holes 12 and 13 , each of several hundred micrometers in diameter. The sleeve 11 is filled with degassed water 14 that has some level of salinity and has a resistivity of about 2000 ohms by cm 2 . Particles are placed in the container 16 retained in the sleeve 11 , the container 16 holds carbide particles 15 that disperse through two small holes 17 , 18 in the container 16 during a shock wave activation. Once activated these particles 15 stay suspended in the saline water 14 and help provide a longer life and higher conductivity of the water 14 for use in the electrode 1 . As shown the sleeve 11 sits over the plastic insulator body 8 which has several hose barb circular seal connections 19 such that the sleeve 11 when pressed over the insulator body 8 makes a gripping attachment. To provide a water tight seal, a metal ring 20 is then pressed over the sleeve 11 and the insulator body 8 overlying this region of barb seal connectors 19 making an extremely tight sealed fit. When the electrode 1 has been used to the point that the tips 3 and 4 are sufficiently burnt that the gap S cannot be maintained between the two electrodes 3 and 4 the entire electrode assembly 1 is generally disposed of. It has come to the attention of the present inventors that this process of simply discarding the used electrode 1 is inefficient in that the electrode is capable of many more uses if the electrode tips 3 and 4 can be repaired such that the gap S between the two electrodes 3 and 4 can be maintained. As a result of this discovery it was determined that if the entire electrode assembly 1 could be disassembled in an efficient manner that the electrode tip 3 formed on the metal inner conductor 9 could be repaired as well as repairing the outer electrode 4 such that the spark gap S can be reestablished. The following description provides a method of disassembling such an electrode device 1 . This device as described above is similar to and is further described in U.S. Pat. No. 6,113,560 which is incorporated herein by reference in its entirety.
[0034] The first step in disassembling the electrode assembly 1 is to place the sleeve 11 in a fixture 30 with a collet collar 32 that grasps the ring 20 holding it in place and thereafter a rod 31 pushes the plastic sleeve 11 free of the ring 20 as shown in FIG. 2 . Once the ring 20 is moved from the retention area around the insulator body 8 and sleeve 11 then the operator disassembling the electrode can simply pull apart by twisting and bending off the plastic sleeve relative to the plastic main body housing 8 . The fluid 14 contained therein can then be poured into a container and the carbide particles 15 can be salvaged if so desired. Alternatively since the saline water 14 and carbide particles 15 are readily available it is possible to simply replace the saline water 14 and carbide particles 15 with new material.
[0035] As shown in FIG. 3A , once the sleeve 11 containing fluid 14 is removed the electrode tips 3 and 4 are exposed and the electrode tip 3 which is an integral part of the metal inner conductor 9 can be observed protruding out of the plastic insulator housing body 8 by an amount of approximately an ⅛ to 3/16 of an inch (3.2 mm) to (4.8 mm). Accordingly by placing the electrode assembly 1 in a holding fixture 42 and pressing the tip 3 using an arbor press 40 while holding the plastic body 8 restrained in the fixture 42 the operator can force the inner conductor 9 to move in a rearward direction at end location 9 A breaking free the insulation grip around the conductor 9 . Once the adhesion of the insulator body 8 is overcome the assembly 1 can then be placed in a holder 44 using the 10 mm collet collar 45 retained in a fixture 46 which will hold onto the exposed end 9 A of the conductor 9 and the operator can push the plastic insulator body 8 free from the conductor 9 or pull the conductor 9 out of the body 8 , as shown in FIG. 3B . At this point the entire conductor 9 with burnt electrode tip 3 has been removed from the insulator body 8 . Once removed, the insulator body 8 now simply holds the outer electrode tip 4 which is retained on two projecting legs 4 A, 4 B and forms a “u” shaped member with the electrode tip 4 in axial alignment with the housing body 8 . Upon visual inspection it can be determined whether the electrode tip 4 needs to be replaced, if it does then it is possible to do this in a rather unique manner which will be described below. First a description of the repair of the electrode tip 3 will follow.
[0036] With reference to FIG. 4 the electrical inner conductor 9 with a burned electrode 3 can be measured so that the amount of burn down can be established. This is done by taking a conductor 9 with a new electrode tip wherein the electrode tip 3 is a conical shape having approximately a 10 degree angle of slope and measuring back to a shoulder 3 A for example if a new electrode tip extends a distance ΔX from the shoulder 3 A, then the amount of material that has been burned down due to use is determined by measuring the electrode tip extends from the shoulder and the difference ΔX is the amount the tip burnt so that the tip can be recut to the original dimension X. This is possible because the inner conductor 9 extends a sufficient distance beyond what is required to make a good electrical connection when in use. Accordingly it is possible to then take the burnt electrode tip, machine back the shoulder 3 A by a distance ΔX with a lathe the 10 degree taper such that the entire tip 3 has been repaired. In order for the electrode conductor 9 to sit properly in the housing body 8 it is then required that the 5 degree shoulder taper must be extended back by the same distance ΔX, such that when the inner electrode conductor 9 is placed back in the plastic housing body 8 it will extend forward a distance sufficient that the tip 3 is precisely back in the location of a new electrode extending the distance X. With reference to FIG. 5 , a height measuring device 50 with an indicator dial 52 is set at a precise zero distance such that when the burnt electrode is placed in a fixture 51 the indicator dial 52 can be rotated down to contact the tip 3 . This distance of roll down is the amount of burn down ΔX that occurred on the tip 3 . Once this dimension is determined it is used to establish the amount of machining required to recut the tip 3 back to the original condition and to reshape the shoulder taper.
[0037] With reference to FIG. 6 , during the process of working with the inner conductor 9 while the entire inner conductor 9 is placed in a lathe 53 it is polished using an abrasive pad such that the conductor 9 is sufficiently cleaned prior to cutting back the electrode tip 3 and shoulder by the amount ΔX as desired. As shown the cutters 55 , 56 are held at end 57 . The tip 3 can be cut after the shoulder end is machined back an amount ΔX after that cut is made the tip is reformed on a 10 angle using a cutter 55 . Thereafter the shoulder taper along surface 3 A is recut to also extend back a distance ΔX so the conductor 9 will fit precisely in its original position thus finishing the repair of the burnt tip 3 . Once cleaned and cut the conductor 9 can then be placed in the container for later reassembly back into the inner layer housing to form a finished electrode product as shown in FIG. 8 .
[0038] At the other side of the electrode assembly device 1 , the electrode tip 4 must be inspected. If the outer electrode tip 4 is sufficiently burnt at the transverse tip portion 4 C, then it needs to be repaired in such a fashion that the original gap setting S can be established. In order to accomplish this task the unique method of repairing this electrode device 1 is accomplished by taking two electrode devices 1 , where one device has a sufficiently undamaged electrode tip 4 that can be polished and cleaned. On each leg 4 A and 4 B, of that electrode 4 the legs are cut from the insulator housing body 8 and cleaned as indicated, as shown in FIGS. 7A and 7B . Once cleaned the electrode tip 4 is placed in a fixture 60 and another insulator body 8 with a burnt tip 4 has the electrode legs 4 A, 4 B cut so that the portion embedded in the plastic body 8 extend and protrude a sufficient distance D from the plastic insulator body 8 . These protruding leg portions 4 A, 4 B on both sides of the insulator body 8 provide a reattachment point for the cut electrode 4 . The cut electrode 4 is placed in the fixture 60 , the insulator body 8 with two protruding legs 4 A, 4 B is inserted into this fixture 60 which has split halves 62 , 64 of a molded phenolic material that duplicate the outer surfaces of the insulator body 8 by cutting the fixture 60 the split halves 62 , 64 can accept and position the legs 4 A, 4 B of the electrode 4 connected to the insulator body 8 and the cleaned electrode 4 can be brought into contact and alignment with the cut legs overlapping such that the original precise gap S can be set between this assembly. Prior to taking the cut electrode 4 and sticking it in the fixture 60 , tubular insulator material two pieces 22 are extended over each leg 4 A, 4 B and brought to the center arch of the electrode 4 such that the tubular insulation 22 are in position to be set along the sides of the legs 4 A, 4 B once the cut protruding legs 4 A, 4 B on the insulating body 8 and the electrode 4 are welded together at location 4 W as illustrated in FIGS. 7B and 7C . This is done by welding a projecting out leg 4 A on the replacement electrode 4 and welding and then repeating the welding for cut legs 4 B to complete the assembly.
[0039] As shown in FIG. 7B , a weld machine 70 is provided wherein welding tips 72 are brought into contact with the protruding legs 4 A on the insulator body 8 and the repaired and polished electrode 4 legs 4 A such that a weld can be made, these welding tips 72 are brought through an opening 66 in the fixture 60 which enables the welding tips 72 to push directly against both pairs of legs 4 A to make a secure fitment as a weldement is occurring. Once welded the electrode 4 in the weld zone 4 W is generally double the thickness and therefore has improved strength and conductivity in this area. Once the welding is accomplished the fixture 60 can be removed and the insulator tubing pieces 22 can be shoved down over the weldement portions 4 W such that the now repaired outer electrode 4 has the appearance of a new electrode 4 . As mentioned the gap S is set prior to welding and is precisely set using a feeler gauge to set the depth, once set and the fixture 60 is locked into position and the weld is made such that the protruding legs are in perfect alignment. As shown in FIG. 7A , 7 B the inner conductor 9 with a repaired tip 3 is already placed in the housing body during welding. This is optional as the weldement 4 W can be made prior to reassembly of the conductor 9 if so desired as described below.
[0040] At this point the electrical inner conductor 9 with a recut electrode tip 3 is placed back into the end of the main insulator body 8 and is pressed fit back into position by placing the electrode 4 in an arbor and having the plastic body 8 in a fixture is possible to smoothly press the conductor 9 back into position as shown in FIG. 8 . It is moved forward to a point wherein the assembly is completely set. At this point it is possible to take a feeler gauge and recheck the spark gap S setting to insure that proper positioning has occurred. This fundamentally is automatic as the distances have been precisely cut or welded to the required distances and the inner conductor 9 can only go forward by the amount of material removed along the taper surface. At this point the entire assembly is ready to have the sleeve 11 containing liquid 14 and carbide 15 reattached. Prior to doing so the operator removes the carbide carrier container 16 press fit from its location in the sleeve 11 and repacks it with fresh carbide 15 . Also a tape 23 is wrapped around the end of the sleeve 11 covering the 2 micrometer holes 17 , 18 that are used for releasing gasses during shock wave treatment as shown in FIG. 9A . This tape 23 is provided with written indication that it must be removed prior to use, once taped and recharged with carbide 15 in the carbide cap carrier container 16 is pressed back into the sleeve 11 and is now ready to have saline solution 14 added. The solution 14 is brought to a fill point on the sleeve 11 and then the filled sleeve 11 and main body 8 are pressed together and thereafter the metal ring 20 is pressed back over the joint interface between the main body 8 and the sleeve 11 creating a water tight seal completing the reassembly of the repaired electrode 1 , as shown in FIG. 9B . Once repaired as described above the electrode 1 is placed in a packaging container ready for shipment.
[0041] Contrary to what was previously reported by the manufacturer it is not required that the insulator material body 8 be cut or ground from the inner conductor 9 , but it can simply be pressed off the inner conductor 9 such that all the components can be repaired, cleaned and reused once the electrode tips 3 and 4 are repaired. These repairs enable the entire device 1 to be repaired in such a fashion that is available for use and the performance characteristics are identical to that of the new electrode. This ability to repair these types of assemblies provides a significant cost savings to the end user. This repaired device provides good spark gap control over a decent amount of use making it desirable that such a device be reusable without requiring an entire new electrode assembly to be purchased, simply because the tips have burnt down slightly and need to be redressed as shown above.
[0042] This repair method while requiring several steps to accomplish is fairly simple in its process as described above and as can be seen accomplishes a repair that meets all of the criteria that the original device had maintained when originally sold. Secondly, the method as described above teaches that the outer electrode 4 could be cut from another electrode assembly and reinstalled on a second electrode assembly as described above. However, it is also possible that one does not need to cut the outer electrode 4 along the two legs, but rather can simply clean those electrodes while also removing the inner conductor and recutting the electrode 3 integral thereto as described above as an alternative method of repair. However, it is also possible that one does not need to cut the outer electrode 4 along the two legs, but rather can simply clean those electrodes while also removing the inner conductor and recutting the electrode 3 integral thereto as described as an alternative method of repair.
[0043] As an additional alternative repair, it is possible the method described above can provide a new outer electrode 4 of similar shape and construction. The new electrode 4 can be welded onto place as described above to achieve the desired result. In this fashion the cannibalization of two electrode devices 1 to build one electrode device 1 would not be required and the repair process would simply replace the outer electrode such that the assembly can be repaired in that fashion prior to being repackaged and reused. These and other alternative constructions are possible when using the method as described above which unexpectedly and very simply is capable of disassembly and reassembly in such a fashion that these electrode assemblies 1 can be easily repaired and put back into service.
[0044] Variations in the present invention are possible in light of the description of it provided herein. While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. It is, therefore, to be understood that changes can be made in the particular embodiments described which will be within the full intended scope of the invention as defined by the following appended claims. | A method of repairing a used electrode device 1 is disclosed wherein the method has the steps of providing a used electrode assembly 1 having an inner conductor 9 with an integral electrode tip 3 encapsulated in an insulator body 8 having an outer conductor 10 and an outer electrode tip 4 C; and pressing the inner conductor 9 with integral electrode tip 3 while holding or restraining the insulator body 8 to apply an force sufficient to overcome at least partially the adhesion forces at the mating surfaces of the inner conductor 9 and the insulator body 8 . Thereafter by grasping an end 9 A of the inner conductor 9 opposite the tip 3 while holding the insulator body 8 and withdrawing the inner conductor 9 from the insulator body 8 the parts can be separated. Then by measuring the amount the inner electrode tip 3 has been burnt as compared to a new tapered tip to establish a cut distance ΔX; and recutting the tip 3 by machining the burnt portion along the tip 3 taper surface toward and into a shoulder 3 A of the inner conductor 9 by a distance equal to the cut distance ΔX the electrode tip can be reshaped. | 8 |
RELATED APPLICATION
We have filed another related application earlier, titled “System and method for node adaptive filtering and congestion control for safety and mobility applications toward automated vehicles system”, copending now at the USPTO, with the same inventor(s) and assignee, and a related subject matter. We incorporate all the teaching of the prior application above, by reference, including any Appendix or figures.
BACKGROUND OF THE INVENTION
The present invention relates to a system that uses the Vehicle to Vehicle and/or the Vehicle to infrastructure communication for safety and mobility applications. The invention provides methods for lane boundary estimation and even some LDW functionality using V2V and/or V2I systems.
Dedicated Short Range Communication (DSRC) is the main enabling technology for connected vehicle applications that will reduce vehicle crashes through fully connected transportation system with integrated wireless devices and road infrastructure. In such connected system, data among vehicles and with road infrastructure will be exchanged with acceptable time delay. DSRC is the enabler for the V2X communication and provides 360 degrees field of view with long range detection/communication capability up to 1000 meter. Data such as vehicle position, dynamics and signals can be exchanged among vehicles and road side equipments, which make the deployment of safety applications, such as crash avoidance systems (warning and control), possible. V2X technology will complement and get fused with the current production crash avoidance technologies that use radar and vision sensing. V2V will give drivers information needed for safer driving (driver makes safe decisions) on the road that radar and vision systems cannot provide. This V2X capability, therefore, offers enhancements to the current production crash avoidance systems, and also enables addressing more complex crash scenarios, such as those occurring at intersections. This kind of integration between the current production crash avoidance systems, V2X technology, and other transportation infrastructure paves the way for realizing automated vehicles system.
The safety, health, and cost of accidents (on both humans and properties) are major concerns for all citizens, local and Federal governments, cities, insurance companies (both for vehicles and humans), health organizations, and the Congress (especially due to the budget cuts, in every level). People inherently make a lot of mistakes during driving (and cause accidents), due to the lack of sleep, various distractions, talking to others in the vehicle, fast driving, long driving, heavy traffic, rain, snow, fog, ice, or too much drinking. If we can make the driving more automated by implementing different scale of safety applications and even controlling the motion of the vehicle for longer period of driving, that saves many lives and potentially billions of dollars each year, in US and other countries. We introduce here an automated vehicle infrastructure and control systems and methods. That is the category of which the current invention is under, where V2X communication technology is vital component of such system, with all the embodiments presented here and in the divisional cases, in this family.
SUMMARY OF THE INVENTION
Lane Boundary Estimation and Host Vehicle Position and Orientation, within the host lane estimation, using V2V (vehicle to vehicle) and/or V2I (vehicle to infrastructure) system, are presented here. Lane boundary detection and tracking is essential for many active safety/ADAS application. It is also very essential for any level of automated system. The lane boundary position enables the tracking of the host vehicle position and orientation inside the lane. It also enables classifying in-lane, adjacent lanes, and other lanes vehicles. These two functionalities (lane boundary estimation and vehicle lane classifications) enable active safety applications (such as LDW, FCW, ACC, or BSD). It also enables the lateral control of the vehicle for lane keeping assist system, or for full lateral control for automated vehicle (automated for one or multiple lane changes). Current technologies for lane boundary detection and tracking are mainly vision-based.
An embodiment for this invention is a method for lane boundary estimation, and even some LDW functionality, using V2V and or V2I system. Some of the features of this embodiment are due to the following:
1—In an automated system, it will be very difficult to detect and track all lane boundaries using a vision system, due to multiple reasons: limited Field of View (FOV) coverage, difficulty seeing lane marking in high traffic scenario, or challenges facing vision system in different environment conditions (poor lane marking, challenging weather, such as ice, snow, or leaves, challenging lighting conditions, upcoming curves at nights, or the like).
2—Poor availability of LDW system in the above conditions, stated in section 1.
3—V2V active safety systems/ADAS are for vehicle to vehicle threat type, and not intended for road attribute threat type, such as drifting away in your lane, as in LDW system. Therefore, having such system using V2V only may save a vision system cost for lane boundary detection and/or LDW.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is for one embodiment, as an example, for representation of development of fully automated vehicles, in stages.
FIG. 2 is for one embodiment of the invention, for a system for automated vehicles.
FIG. 3 is for one embodiment of the invention, for a system for automated vehicles.
FIG. 4 is for one embodiment of the invention, for automated vehicle functional architecture.
FIG. 5 is for one embodiment of the invention, for automated vehicle infrastructure architecture.
FIG. 6 is for one embodiment of the invention, for a system for V2X landscape, with components.
FIG. 7 is for one embodiment of the invention, for a system for framework for V2I applications, with components.
FIG. 8 is for one embodiment of the invention, for a system for automated vehicle command and control (C2) cloud, with components.
FIG. 9 is for one embodiment of the invention, for a system for Savari C2 network, with components, showing communications between networks and vehicles.
FIG. 10 is for one embodiment of the invention, for a system for host vehicle, range of R values, region(s) defined, multiple nodes or vehicles inside and outside region(s), for communications between networks and vehicles, and warning decisions or filtering purposes.
FIG. 11 is for one embodiment of the invention, for a system for host vehicle, range of R values, region(s) defined, for an irregular shape(s), depending on (x,y) coordinates in 2D (dimensional) coordinates, defining the boundaries.
FIG. 12 is for one embodiment of the invention related to virtual boundaries and clustering vehicles.
FIG. 13 is for one embodiment of the invention related to current and history of data for vehicles.
FIG. 14 is for one embodiment of the invention related to clustering, distances between clusters, and statistical distributions for vehicles.
FIG. 15 is for one embodiment of the invention, for a system for lane determination.
FIG. 16 is for one embodiment of the invention, for a system for clustering.
FIG. 17 is for one embodiment of the invention, for a system for clustering and cluster analysis.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is for one embodiment, as an example, for representation of development of fully automated vehicles, in stages, for progression toward fully automated vehicles. FIG. 2 is for one embodiment of the invention, for a system for automated vehicles, using GPS, independent sensors, and maps, for vehicle interactions, driving dynamics, and sensor fusions and integrations.
FIG. 3 is for one embodiment of the invention, for a system for automated vehicles, with different measurement devices, e.g., LIDAR (using laser, scanner/optics, photodetectors/sensors, and GPS/position/navigation systems, for measuring the distances, based on travel time for light), radar, GPS, traffic data, sensors data, or video, to measure or find positions, coordinates, and distances. The government agencies may impose restrictions on security and encryption of the communications and data for modules and devices within the system, as the minimum requirements, as the hackers or terrorists may try to get into the system and control the vehicles for a destructive purpose. Thus, all of our components are based on those requirements imposed by the US or other foreign governments, to comply with the public safety.
FIG. 4 is for one embodiment of the invention, for automated vehicle functional architecture, for sensing, perception, applications, and actuation. FIG. 5 is for one embodiment of the invention, for automated vehicle infrastructure architecture, for sensing, gateway, and services.
FIG. 6 is for one embodiment of the invention, for a system for V2X landscape, with components, for spectrum and range of frequencies and communications, for various technologies, for various purposes, for different ranges. FIG. 7 is for one embodiment of the invention, for a system for framework for V2I applications, with components, for road-side platform and on-board platform, using various messages and sensors.
FIG. 8 is for one embodiment of the invention, for a system for automated vehicle command and control (C2) cloud, with components, with various groups and people involved, as user, beneficiary, or administrator. FIG. 9 is for one embodiment of the invention, for a system for Savari C2 network, with components, showing communications between networks and vehicles, using traffic centers' data and regulations by different government agencies.
FIG. 10 is for one embodiment of the invention, for a system for host vehicle, range of R values, region(s) defined, multiple nodes or vehicles inside and outside region(s), for communications between networks and vehicles, and warning decisions or filtering purposes, for various filters to reduce computations and reduce the bandwidth needed to handle the message traffic. FIG. 11 is for one embodiment of the invention, for a system for host vehicle, range of R values, region(s) defined, for an irregular shape(s), depending on (x,y) coordinates in 2D (dimensional) coordinates, defining the boundaries, or in 3D for crossing highways in different heights, if connecting.
In one embodiment, we have the following technical components for the system: vehicle, roadway, communications, architecture, cybersecurity, safety reliability, human factors, and operations. In one embodiment, we have the following non-technical analysis for the system: public policy, market evolution, legal/liability, consumer acceptance, cost-benefit analysis, human factors, certification, and licensing.
In one embodiment, we have the following requirements for AV (automated vehicles) system:
Secure reliable connection to the command and control center Built-in fail-safe mechanisms Knowledge of its position and map database information (micro and macro maps) Communication with traffic lights/road side infrastructure Fast, reliable, and secure Situational awareness to completely understand its immediate surrounding environment Requires multiple sensors Algorithms to analyze information from sensors Algorithms to control the car, for drive-by-wire capability
In one embodiment, we have the following primary technologies for our system:
V2X communication: time-critical and reliable, secure, cheap, and dedicated wireless spectrum Car OBE (on-board equipment): sensor integration (vision, radar and ADAS (advanced driver assistance system)), positioning (accurate position, path, local map), wireless module (physical layer (PHY), Media Access Control (MAC), antenna), security (multi-layer architecture), processing and message engine, and algorithms for vehicle prediction and control
In one embodiment, we have the following building blocks for AVs:
Automation Platform
i. Advanced Driver Assistance (ADAS) integration ii. Map Integration, Lane Control iii. Radio communications support iv. Vehicle Controller Unit to do actuation
Base Station
Ground positioning support to improve positioning accuracy V2I (vehicle to infrastructure) functionality, support for public/private spectrums Cloud connectivity to provide secure access to vehicles
Command Control Center
i. Integration with Infrastructure Providers
Here are some of the modules, components, or objects used or monitored in our system: V2V (vehicle to vehicle), GPS (Global Positioning System), V2I (vehicle to infrastructure), HV (host vehicle), RV (remote vehicle, other vehicle, or 3 rd party), and active and passive safety controls.
FIG. 12 is for one embodiment of the invention related to virtual boundaries and clustering vehicles, to find the location and width of the lanes, with virtual boundaries. FIG. 13 is for one embodiment of the invention related to current and history of data for vehicles, for previous times, tk to t k-n , tracking the vehicles, e.g. with snap shots in time, in a sequence of locations.
FIG. 14 is for one embodiment of the invention related to clustering, distances between clusters (e.g. center to center, D cc ) (as a multiple integer (K) of a lane width (W)), and statistical distributions for vehicles (to distinguish the clusters, based on distribution curve/statistics, e.g. normal distribution, of the coordinates of vehicles' positions, at various time intervals). So, we have: D cc =K W
wherein K is a positive integer (as 1, 2, 3, 4, . . . ). Even with 2 lanes, we have 2 clusters, and one D cc value. Thus, we can get the value for W (with K=1). The more lanes and more clusters (and cars), the more accurate the value for W.
FIG. 15 is for one embodiment of the invention, for a system for lane determination, based on path history, virtual boundary, maps, GPS, and clustering analysis, determination, and distance measurements. FIG. 16 is for one embodiment of the invention, for a system for clustering, based on statistical analysis, distance measurements, and history, e.g. matching and setting the center of the corresponding cluster with the location of peak of the statistical curve in FIG. 14 , in each of the 2 dimensional axes, for X and Y coordinates. This gives us the 2 coordinates of the cluster center for each cluster. Then, from those coordinates, the distances between the centers of the 2 clusters can be obtained, in each direction or axis, as a subtraction or difference of values, which yields the width of a lane, in one of those 2 directions.
FIG. 17 is for one embodiment of the invention, for a system for clustering, based on statistical analysis, statistical distribution of vehicles, clusters' center-to-center measurements, merging overlapping clusters (if they belong to the same cluster), edge of cluster determination, and coordinates of vehicles, to determine regions and lanes, as shown above.
Here, we describe a method, as one embodiment, for Lane Boundary Estimation:
The lane boundary estimation method uses fused data from nodes (vehicles) current positions, positions history (path history), host vehicle position and path history, host vehicle dynamics (speed, yaw rate, and for some embodiments, acceleration), map database geometrical shape points and attributes, and the dynamic of the vectors that connect the host vehicle with other remote vehicles. (See FIGS. 12-14 .)
To estimate the lane boundaries locations (virtual boundaries), it is required to estimate the road shape, lane width, and a placement technique. To do that, let us look at FIG. 12 and FIG. 13 , as an example:
The map database provides very accurate representation of the geometric shape of the road. The path history can also provide a good representation of the road geometry. The vehicles (nodes) positions distribution can also provide a good representation of the road geometry. If there are not enough vehicles to estimate road geometry, a combined path history and current vehicles distribution can be used to estimate the road geometry, to extrapolate or interpolate between them. Based on the estimated geometry, the vehicles can be grouped/clustered in each lane. This can be performed using a straight piecewise clustering algorithm, spline-based, or an incremental clustering algorithm. Other methods may also be used. Basically, when the road curvature data is available, any clustering method will be based on matching the vehicle positions to a longitudinal grid of the road representation. (See FIGS. 12-14 .) Only vehicles that their heading angle measurement (GPS measurements) aligned with the forward road heading will have high confidence to be a good data. The vectors can be used here, as one example. As one example, the direction matching can be done by dot-products of 2 vectors (V1 and V2):
V 1 V 2 cos α
wherein α is the angle between the 2 vectors (V1 and V2). Note that for perfectly aligned vectors, we have a equal to zero, or (cos α=1) (or at maximum value).
Once every lane cluster is established, a combination of clusters separation distances are calculated (see FIG. 12 ). One method is the following, as an example:
1—Calculate lateral distance (perpendicular to the road tangent) between host lane cluster and all other lane clusters, and between all lane clusters. For example, in FIG. 12 , we have the average distance between cluster M (middle one) and cluster L (left one) (distance_ML), the average distance between cluster M and cluster R (right one) (distance_MR), and the average distance between clusters L and R (distance_LR).
2—Let us assume, as an example, that distance_ML=3 meter, distance_MR=4 meter, and distance_LR=7.2 meter. Then, an average lane width is between 3 and 4 meter. Therefore, distance_ML corresponds to one lane width, distance_MR corresponds to one lane width, and distance_LR correspond to two lane width. Therefore, an estimated lane width can be calculated: ((3+4+(7.2/2))/3)=3.53 meter. (See FIGS. 12-14 .)
3—Now, we would like to establish where the virtual boundaries are located. The middle of the host lane is estimated (as one example) as the line that is located at the average between the line that is generated from left-shifting the right cluster line by one lane width and the line that is generated from the right-shifting the left cluster line by one lane width. (See FIGS. 12-14 .)
4—Other lanes are distributed, by shifting this middle host lane by one lane width. (See FIGS. 12-14 .)
5—Once middle line is established and the lane width is estimated, the virtual lane boundary locations are estimated/found (see FIGS. 12-13 ).
6—The number of lanes map database attributes can also be used in the above calculations, as one embodiment. For example, using the number of lanes limits or determines the width of the whole road, the location of the shoulders, and expectation of locations of the cars in different lanes. (See FIGS. 12-14 .)
Next, let us look at the Host Vehicle Position and Orientation within the host lane:
Now, the left and right host vehicle virtual boundaries and host vehicle middle lane are estimated. The host vehicle position is known. Therefore, the vehicle position with respect to the middle line and/or to the left and right boundaries can be easily calculated from the above values (see FIGS. 12-13 ), using difference of distances or values (see FIGS. 12-13 ), as they all refer to the same position or location on the road (or on the road coordinate system), from both ways.
The heading angle of the road at the vehicle position can be calculated from the road geometry estimation. Also, the vehicle heading angle is obtained from the GPS data. Therefore, the heading angle with respect to the lane can be calculated easily by differencing the two values. These two parameters (position and heading angle with respect to the host lane) can be used to design an LDW system, as an example.
Another method to do the estimating of these two parameters is using modeling and estimation. All of the above measurements, in addition to the vector representation that connect the host vehicle with other vehicles and the host vehicle yaw rate, can be fused together (in a state model), to estimate these two main parameters (position and heading with respect to the lane). For example, we have:
dD/dt =sin(Heading)*HostSpeed
d Heading/ dt =RoadCurvature−(HostSpeed*YawRate)
d RoadCurvature/ dt= 0
wherein D is the distance from the middle of the host lane, Heading is the heading or direction or angle with respect to the road, RoadCurvature is the curvature of the road, “t” is the time, HostSpeed is the speed of the host vehicle, YawRate is the rate of yaw (e.g., related to vehicle's angular velocity, or e.g., which can be measured with accelerometers, in the vertical axis), and (d( )/dt) denotes the derivative of a function or a variable with respect to variable “t”.
Other models of curvature can also be used, such as the Clothoid model. For the Clothoid, e.g., as one embodiment, the curvature varies linearly with respect to the parameter t. It is one of the simplest examples of a curve that can be constructed from its curvature. There are also Clothoids whose curvature varies as the n-th power of the parameter t, as another embodiment.
The measurements for the above state model can be the following parameters or set, as one example: {vector between the host vehicle and other vehicles (range and angle), curvature, heading difference, difference in position}.
Now, let us look at the advantages (comparison):
Estimating lane boundaries, when vision system does not exists, or exists, but not fully functional. In an automated system, it will be very difficult to detect and track all lane boundaries using a vision system, due to multiple reasons: limited Field of View (FOV) coverage, difficulty seeing lane marking in high traffic scenario, or challenges facing vision system in different environment conditions (e.g., poor lane marking, challenging weather, such as ice, snow, or leaves, challenging lighting conditions, upcoming curves at nights, or the like). Poor availability of LDW system in the above conditions, stated in the section above. V2V active safety systems/ADAS are for vehicle to vehicle threat, and not intended for road attribute threats, such as drifting away in your lane, as in LDW system.
As shown above, the advantages of our methods are very clear over what the current state-of-the-art is, e.g. using vision systems.
In this disclosure, any computing device, such as processor, microprocessor(s), computer, PC, pad, laptop, server, server farm, multi-cores, telephone, mobile device, smart glass, smart phone, computing system, tablet, or PDA can be used. The communication can be done by or using sound, laser, optical, magnetic, electromagnetic, wireless, wired, antenna, pulsed, encrypted, encoded, or combination of the above. The vehicles can be car, sedan, truck, bus, pickup truck, SUV, tractor, agricultural machinery, entertainment vehicles, motorcycle, bike, bicycle, hybrid, or the like. The roads can be one-lane county road, divided highway, boulevard, multi-lane road, one-way road, two-way road, or city street. Any variations of the above teachings are also intended to be covered by this patent application. | Lane Boundary Estimation and Host Vehicle Position and Orientation, within the host lane estimation, using V2V (vehicle to vehicle) system, are discussed here. Lane boundary detection and tracking is essential for many active safety/ADAS application. The lane boundary position enables the tracking of the host vehicle position and orientation inside the lane. It also enables classifying in-lane, adjacent lanes, and other lanes vehicles. These two functionalities (lane boundary estimation and vehicle lane classifications) enable active safety applications (such as LDW, FCW, ACC, or BSD). It also enables the lateral control of the vehicle for lane keeping assist system, or for full lateral control for automated vehicle (automated for one or multiple lane changes). | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a folder device. In particular, the present invention relates to a device designed to fold one terminal portion of an elongated piece of sheet material through 180° in relation to the remainder of the piece.
The invention finds application to marked advantage in the art field of packaging generally, and in the field of packaging of commodities for smokers in particular; indeed reference is made specifically to this very application throughout the disclosure, albeit no limitation in general scope being implied.
In conventional packaging systems, the operation of bending one portion of a piece of sheet material through 180° would be effected by means of a unit comprising two distinct folders arranged in series, one of which would be a fixed folding element generally of helical geometry.
To the end of reducing the relatively cumbersome dimensions of such folding units, U.S. Pat. No. 4,188,024 discloses a device in which an elongated piece of material is bent through 180° by the action of a single folder provided in the form of a flat rod which is capable of movement generated along a predetermined operating trajectory by two distinct transmission linkages, of which the embodiment and control involve notable drawbacks in terms of construction and cost.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a device for effecting a fold of 180° in an elongated piece of sheet material, from which the drawbacks mentioned above are absent.
The stated object is realized according to the present invention in a folder device which includes a flipper, and operating means by which the flipper is displaced along a predetermined fold trajectory. The operating means include actuator means by which a first point on the flipper is displaced along a first trajectory, and reaction means interacting with the flipper, by which the flipper is caused to rotate about a first axis passing through the first point as the first point is displaced along the first trajectory.
In a preferred embodiment of the folder device, the first trajectory is a rectilinear trajectory, and the reaction means advantageously comprise guide means coupled to a second point on the flipper and serving to displace the selfsame second point along a second trajectory, likewise rectilinear, extending at an angle other than zero in relation to the first trajectory.
Preferably, the actuator means include a first track extending along the first trajectory, also first coupling means by which the first point on the flipper is caused to traverse slidably along the first track and to rotate about the first axis, and a linear actuator by which the first point on the flipper is displaced along the first track. Again preferably, the guide means include a second track extending along the second trajectory, and second coupling means by which the second point on the flipper is caused to traverse slidably along the second track and to rotate about a second axis disposed parallel to the first axis and passing through the second point.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in detail, by way of example, with the aid of the accompanying drawings, in which:
FIG. 1 shows a preferred embodiment of the folder device according to the present invention, seen in a side elevation;
FIG. 2 is a further elevation of the device shown in FIG. 1;
FIG. 3 is a view as in FIG. 1, showing the device in a different operating position;
FIG. 4 is the section through IV--IV in FIG. 3;
FIG. 5 is the perspective view of a folding unit incorporating the device of FIGS. 1 . . . 4;
FIGS. 6 . . . 10 show the unit of FIG. 5 in a succession of different operating positions, shown on a smaller scale, and with certain parts omitted for clarity.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIGS. 1, 2 and 3 of the drawings the numeral, 1 denotes a folder device comprising a fixed pedestal frame 2 of upturned "L" profile, composed of a pillar 3 and an arm 4, disposed at right angles one to another, also a flipper 5 of substantially rectangular shape providing a flat lateral working surface 6, which is cantilevered from the pillar 3 on the same side as the arm 4.
The flipper 5 is associated with the pillar 3 by way of slide-and-track guide means 7 and 8, each comprising a respective rectilinear slot 9 and 10 fashioned in the pillar 3 and providing the track part of such means. More exactly, the one slot 9 extends substantially the full length of the pillar 3 in a direction substantially perpendicular to the arm 4, whereas the remaining slot 10 occupies a terminal portion of the pillar 3, which is remote from the portion which is associated with the arm 4, disposed convergent with the first slot 9 and the arm 4 in such a way that the angle A compassed by the two slots 9 and 10 is an acute angle, preferably of the order of 50°.
The guide means 7 and 8 also comprise respective slides 11 and 12, each engaging in and thus capable of movement along the corresponding slot 9 and 10, which are connected to the flipper 5 in such a way as to allow their rotation about respective axes 13 and 14, which is disposed parallel one with another and with the flat working surface 6 of the flipper 5, and perpendicular to the pillar 3.
Each slide 11 and 12 is composed of two blocks 15 and 16 aligned on the respective axis 13 and 14 and united by a respective pair of screws 17. The blocks 15 and 16 comprise respective portions 18 and 19 which are connected rigidly by the screws 17 and present respective flanges 20 and 21 by which the portions 18 and 19 are restrained axially within the respective slots 9 and 10. With reference also to FIG. 4, each block 16 is embodied with a blind hole 22 positioned to accept a first pin 23 issuing from one side of the associated block 15, which also provides a second pin 24 projecting from the opposite side and seated pivotably, restrained in the axial direction, within a respective through-hole 25 provided by the flipper 5 in a position of coaxial alignment with the corresponding axis 13 and 14 of rotation.
The flipper 5 provides a bevelled edge 26 which is contiguous to the flat lateral working surface 6 on the side farthest from the arm 4, which extends parallel to the two axes 13 and 14 of rotation.
The flipper 5 is supported by a linear actuator 27 and thus is capable of movement, brought about by the actuator 27, along a predetermined fold trajectory between a first limit position indicated in FIG. 1, in which the flipper 5 is disposed nearly perpendicular to the arm 4, and a second limit position in which the flipper 5 lies substantially parallel to and with the working surface 6 directed up toward the arm 4. When the flipper 5 is disposed in the first limit position, each slide 11 and 12 occupies a substantially terminal portion of the respective slot 9 and 10 at the end nearer the arm 4, with the slide 11 of the guide means denoted 7, in particular, impinging directly on the extremity of the respective slot adjacent to the arm 4. When the flipper 5 is in the second limit position, the two slides 11 and 12 occupy terminal portions of the slots 9 and 10 at the end remote from the arm 4, with the slide 12 of the guide means 8, in particular, impinging directly on the extremity of the respective slot 10 farthest from the arm 4. Again observing FIGS. 1 to 3, the linear actuator 27 passes through a slot 28 fashioned in the arm 4, and comprises a body section 29 of which a terminal portion is hinged to the arm 4 by way of a pair of trunnions 30, in such a way that the actuator 27 is pivotably associated with the frame 2, able to rock on an axis 31 disposed parallel to the axes 13 and 14 of rotation and at right angles to the body 29 itself. The rod 32 of the actuator 27 is hinged, in turn, to the second pin 24 of the nearer slide 11 by way of an end mounting 33, which is positioned internally of a recess 34 fashioned in the flipper 5 and bridged by the pin 24.
FIG. 5 illustrates a folding unit 35, incorporating the folder device 1 described above, by which the end flap 37 of a die-cut sheet 36, e.g., of the type which is utilized to fashion a rigid packet (not illustrated) for cigarettes (likewise not illustrated), is bent through 180°. More exactly, the die-cut sheet 36 further comprises an intermediate panel 37', which is located adjacent to the end flap 37 and destined to provide the front face (not illustrated) of the hinged lid (not illustrated) upon completion of the packet (not illustrated). Thus, the flap 37 is rotated through 180° by the unit 35 and flattened against the intermediate panel 37' in such a manner as to create a reinforcement for the front face of the lid.
To this end, the unit 35 comprises a conveyor 38, in addition to the device 1 described above, on which die-cut sheets 36 advance singly and in succession along a predetermined feed path P that extends parallel with the axes 13 and 14 of the guide means and with the arm 4, passing through a station 39 at which each end flap 37 is folded over the corresponding intermediate panel 37'. The conveyor 38 comprises a fixed bed 40 extending parallel with the arm 4, by which the die-cut sheets 36 are supported slidably during their progress along the feed path P. The part of the bed 40 directed toward the device 1 exhibits a first lateral edge 41 occupying a first portion of the folding station 39, from which the end flap 37 of each successive die-cut sheet 36 will project when the unit is in operation. The part of the bed 40 that coincides with the pillar 3 is bounded by a second lateral edge 42, lying beyond the first edge 41 along the feed direction of the conveyor 38, which is recessed from the first edge 41 by a distance which is at least equal to the width of the flap 37 and extends beneath a plate 43 disposed parallel with and above the bed 40, separated from the conveying surface by a gap marginally greater than the thickness of the die-cut 36.
The operation of the unit 35 will now be described with reference, for the sake of simplicity, to just one die-cut sheet 36 advanced by the conveyor 38 along the feed path P and through the folding station 39, and departing from the configuration in which the flipper 5 is suspended from the linear actuator 27 in the first limit position. In this situation, the actuator 27 is extended to traverse the slides 11 and 12 along the respective slots 9 and 10, with the result that the one axis 13 is displaced along a predetermined trajectory, a rectilinear trajectory in the instance of the example illustrated, and the flipper 5 is made to rotate about the axis 13 by reason of the reaction force applied through the bounding surface of the slide denoted 12, of which the respective slot 10 functions as a reaction bearing.
With the flipper 5 thus in motion, and a die-out sheet 36 entering the station 39 and passing over the first edge 41 of the bed 40, the bevelled edge 26 engages initially in contact with the outer edge of the end flap 37 (FIG. 6), then continues on its trajectory, impinging on and sliding across a middle portion of the flap 37 (FIG. 7) to the point of forcing a bend to be created, which is substantially square with the fixed bed 40. As the flipper 5 moves on, the flap 37 is engaged by the working surface 6 (FIG. 8) and forced progressively further toward the intermediate panel 37' (FIG. 9), to the point at which the two thicknesses 37 and 36 are finally flattened against one another (FIG. 10) and forced under the plate 43 to complete the 180° fold.
Thus, the operation of folding an elongated piece of material, and more exactly the end flap 37 of a die-cut sheet 36, is obtained in extremely simple fashion, by providing and making use of a flipper 5 capable of movement along two tracks, provided by respective slots 9 and 10, and utilizing a single linear actuator 27. | A device for folding flat die-cuts through 180° has a flipper of which the movement is guided by linkages composed of at least two rectilinear slots, occupying a common plane and compassing an acute angle, and at least two slides free to traverse along the two slots. The flipper is connected pivotably to the slides, and the folding action is generated by a single linear actuator stroking in a direction substantially parallel to one of the slots, its rod end being hinged to the respective slide. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a drive mechanism and transmission for an automatic washer of the type in which clothes are washed by oscillation of a vertical agitator and subsequently have water centrifugally removed therefrom by high speed rotation of a wash basket.
2. Description of the Prior Art
Automatic laundry appliances having a pre-selected programmed cycle of operation which includes a washing period during which oscillation of an agitator imparts a movement to clothes enclosed in a wash basket and a water removal period during which the wash basket is rotated at a high speed are known in the art. It is also known in the art to operate the components of the machine during different periods of the cycle by a common drive means. When a single drive means is utilized, it is necessary to provide a transmission having a shift means which can be operated to selectively condition the drive means to supply oscillatory motion to the agitator, or to supply rotational motion to the wash basket.
It is known in the art to impart oscillatory motion to a vertical agitator by means of a lever connected to an eccentric and a segmental gear which engages a circular gear co-rotational with the agitator axis.
SUMMARY OF THE INVENTION
A transmission shift mechanism for a vertical axis oscillating agitator laundry appliance has a rotating drive gear on which is mounted an eccentric. The eccentric rotates in a circular aperture in one end of a rack, thereby imparting oscillatory motion to the rack in a plane perpendicular to the agitator axis. The opposite end of the rack has a loop which surrounds the agitator shaft and has teeth thereon which engage teeth carried on the circumference of a pinion which is rotatably mounted on the agitator shaft. The pinion has a second set of teeth formed on a bottom surface thereof which engage teeth carried on the upper surface of a sleeve co-rotatable with the agitator shaft to form a jaw clutch. The oscillatory motion imparted to the pinion by the rack may thereby be transferred to the sleeve to oscillate the agitator shaft.
A cam means for engaging and disengaging the jaw clutch comprises a pair of collars having engageable cam ramp surfaces disposed below a portion of the pinion and surrounding the sleeve which is co-rotatable with the agitator axis. The upper collar is maintained in a rotationally stationary position while the agitator shaft oscillates inside of it.
The lower collar carries two upwardly extending projections about its exterior, and is rotatable by abutment against the projections of two tynes carried on an end of an eccentrically controlled shifter fork. Rotation of the eccentric in one direction will cause one of the tynes on the shifter fork to abut one of the projections on the lower collar. The ramps of the cam surfaces are coordinated with the direction of rotation of the eccentric such that movement of the eccentric in a first direction will cause a first tyne to abut a projection to rotate the lower collar to move the ramps out of engagement and raise the upper collar, thereby raising the pinion and disengaging the teeth of the jaw clutch. Rotation of the eccentric in an opposite direction causes the other of the tynes on the shifter fork to abut the other projection on the lower collar, rotating the lower collar to re-engage the cam ramp surfaces, thereby allowing re-engagement of the jaw clutch pinion teeth with the teeth on the sleeve.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view, partly broken away, of a vertical axis laundry appliance.
FIG. 2 is a detailed sectional view of the wash basket, agitator and associated drive means of the laundry appliance of FIG. 1.
FIG. 3 is a cross-sectional view taken along line III--III of FIG. 2.
FIG. 4 is a view taken along line IV--IV of FIG. 3.
FIG. 5 is a view taken along line V--V of FIG. 3.
FIG. 6 is a detailed sectional view of the clutch mechanism shown in FIG. 3.
FIG. 7 is a view taken along line VII--VII of FIG. 6.
FIG. 8 is a schematic view of the shifter mechanism of FIG. 3 showing the shifter fork in various positions during the cycle of operation.
FIG. 9 is an exploded view of the clutch mechanism of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An automatic laundry appliance is generally illustrated in FIG. 1 at 10 as comprising a tub 19 which has a perforate clothes container or spin basket 21 contained therein and an agitator 22 vertically disposed within the spin basket 21, mounted for oscillatory movement with respect thereto. The basket 21 is mounted for spinning movement during centrifugal extraction of water from the clothes within the basket 21. The tub 19, the spin basket 21, the agitator 22 and a drive mechanism 23 therefor are contained in a cabinet 11.
The cabinet 11 has a top 12 having a hinged lid 13 which is opened to afford access to a clothes-receiving opening 24 which is defined by a tub ring 20 extending about the tub and over a corresponding opening in the spin basket 21. The cabinet 11 also includes a program controller including a timer dial 16 connected to a timer 15 which is mounted on a control panel portion 14 of the cabinet 11. Suitable wiring connects the timer 15 to the drive mechanism 23 and to other electrical components of the appliance to control operation of a wash cycle as is well known in the art. The program controller provides the washing appliance with a sequence of events including agitating the clothes load in a washing portion, spinning the clothes load in the basket 21 to centrifuge the washing liquid therefrom, agitating the clothes load in a rinsing portion, and spinning the clothes load in the basket 21 to centrifuge the rinsing liquid therefrom. The timer dial 16 and the timer 15 may be mounted in any desired location and are shown in the present location for illustrative purposes only.
All components inside the cabinet 11 are supported by struts 17, having a suspension system 18 connected thereto to minimize vibration. Referring to FIG. 2, the drive mechanism 23 also operates a pump 43. The drive mechanism 23, and other components such as a transmission housing 32 and a motor housing 42, are suspended from a mounting plate 25 by mounting means such as a bolt and sleeve arrangement 36. Portions of hoses 43a associated with the pump are also illustrated in FIG. 2. The tub 19 is also mounted to the mounting plate 25 by means of bolts such as 26. A grommet 41 maintains a water-tight relationship between the tub 19 and an agitator encasement column 40. A brake means 35 is also provided to operate in association with a spin tube 107 and an agitator shaft 30, and has a dish shaped member mounted to the mounting plate 25.
The agitator 22 is attached to the agitator shaft 30 by threaded means 31 and the spin basket 21 is attached to the spin tube 107 by threaded drive block means 34.
The shifting mechanism is shown in detail sectional views in FIGS. 3, 6 and 7, and in an exploded view in FIG. 9. The agitator shaft 30 extends into a receptacle 33 in the housing 32 and rests on a bearing plate 37 and a bearing 35 allowing rotation of the shaft 30 about its central vertical axis with a minimum of friction.
Oscillatory movement is imparted to the agitator shaft 30 as follows. As shown in FIGS. 3 and 4, a worm gear 85 is attached to a drive shaft 105 journaled in transmission housing 32 and driven by a motor contained in the housing 42 (FIG. 2). The worm 85 engages teeth 84 on a main drive gear 83, thereby imparting rotational movement to the drive gear 83 about a jack shaft 80. A washer 86 reduces friction between the housing 32 and the drive gear 83. An eccentric 95 is integrally formed on an upper portion of the main drive gear 83. The jack shaft 80 and the agitator 30 are parallel to each other, and a rack shown generally at 92 is disposed in a plane normal to the shafts.
The rack 92 has a circular aperture 108 at one end thereof which receives eccentric 95. An opposite end of the rack 92 has a loop 93 which surrounds the agitator shaft 30. A row of teeth 94 are carried on one side of the loop 93 and engage teeth 53 which are carried on a portion of the exterior of a pinion 52 which rotates freely about the agitator shaft 30. The side of the loop 93 opposite the teeth 94 has a smooth bearing surface 106 which moves against a portion of the exterior of the pinion 52 which has no teeth thereon, thereby insuring complete engagement of the teeth 53 on the pinion 52 and the teeth 94 on the rack 92. As the eccentric 95 is rotated by the main gear 83, a reciprocal motion in a plane normal to the agitator shaft 30 is imparted to the rack 92. This reciprocatory motion is transferred to the pinion 52 by means of engagement of the teeth 94 and 53. Oscillatory motion is thus transferred to the pinion 52. This motion is then transferred to the agitator shaft 30 through a jaw clutch means described below.
The pinion 52 has a second set of teeth 54 integrally formed on a lower portion and disposed downwardly to form the driving member of the jaw clutch. (See FIG. 9). The circumference of the lower toothed portion of pinion 52 is slightly less than the circumference of the main portion of the pinion, thereby forming an annular ledge 57 which is normal to the agitator shaft 30. The teeth 54 on the pinion 52 are arranged to engage similar teeth 55 carried on an upper surface of a sleeve or driven member 56 of the jaw clutch. The sleeve 56 has holes 60 (FIG. 9) disposed in the side walls thereof, which receive a pin 62. The pin 62 also passes through a bore 61 disposed in the agitator shaft 30. Insertion of the pin 62 in the holes 60 and the bore 61 maintains the sleeve 56 in co-rotatable relation to the agitator shaft 30. Although the pinion 52 is free to rotate about the agitator shaft 30, when the teeth 54 and 55 are engaged, the oscillatory motion of the pinion 52 is transferred to the sleeve 56 so that the motion is in turn transferred to the agitator shaft 30.
As shown in FIG. 6, the teeth 54 and 55 are maintained in engagement by means of a biasing spring 51 which abuts an upper surface of the pinion 52. An upper portion of the spring 51 bears against a snap ring 50 which is maintained in position by being placed in a circumferential groove (not shown) in the agitator shaft 30.
It is desired to maintain the jaw clutch teeth 54 and 55 in engagement only during the agitate portion of the laundry appliance cycle to oscillate the agitator 22, and to disengage the teeth 54 and 55 during a spin portion of the cycle so that the agitator is free to rotate with the spin basket 21. When this sequence of events is repeated, it is then desirable to re-engage the teeth 54 and 55 to allow the oscillatory motion of the agitator to again result. Referring to FIGS. 6, 7 and 9, engagement and disengagement of the teeth 54 and 55 is accomplished by cam means including a pair of collars 63 and 71, disposed between the pinion 52 and a base washer 75 and also surrounding the agitator shaft 30 and sleeve 56. The upper collar 63 has a plurality of downwardly extending cam ramp surfaces 70, and the lower collar 71 has the same number, for example three, upwardly extending mating cam ramp surfaces 72. Both collars 63 and 71 are free to rotate about the agitator shaft 30. The upper collar 63 is maintained in a rotationally stationary position relative to the agitator shaft 30 by means of a radially protruding anchor 64 which has a hole 65 vertically disposed therein. A stud 66 inserted into a hole 65 and extending into a receptacle 67 in the housing 32 allows limited vertical motion of the upper cam member 63 in relation to the agitator shaft 30, but prevents rotational movement relative thereto. A vertical pin 76 extending from the base washer 75 also extends into the hole 65 in the anchor 64 so that rotation of the base washer 75 is also prevented.
The lower collar 71 has an exterior portion 73, with two upwardly extending lugs 74A and 74B mounted thereon approximately 140° apart. A thin wall web member 109 extends between the lugs 74A and 74B to prevent interference between a shifter fork 96 and upper collar 63. An appropriate force imparted to the lugs 74A and 74B will thus rotate the lower collar 71 in an appropriate direction to effect engagement or disengagement of the cam ramp surfaces 70 and 72. When the cam ramp surfaces 70 and 72 are disengaged, the upper cam member 63 is raised the height of the cam ramp surface 72 and pushes against the surface 57 on the pinion 52 through a washer 58, thereby raising the pinion by an identical distance to disengage the jaw clutch teeth 54 and 55. The spring 51 is compressed slightly to allow such movement.
The appropriate force to rotate the lower collar 71 is applied to the lugs 74A and 74B by the shifter fork 96. The shifter fork 96 is operated by the eccentric 95 and is located between the rack 92 and the main drive gear 82 (see FIGS. 3 and 4). A recess 100 is provided at one end of the shifter fork 96, so that the shifter fork 96 may partially surround the upper collar 63. A pair of tynes 101A and 101B extend downwardly from the shifter 96 and are arranged to abut lugs 74A and 74B respectively.
Operation of the shifter fork is demonstrated in FIGS. 5 and 8. The position of the tynes 101A and 101B with respect to the lower collar 71 is determined by the direction of rotation of the eccentric 95. The shifter fork 96 is acted upon by the frictional drag forces created between the shifter fork 96, the rack 92, the upper surface of the drive gear 83 and the outer peripheral surface of the eccentric 95.
The positioning of the shifter fork 96 during the agitate portion of a wash cycle is shown in FIG. 5. The drive gear 83 is being driven in a clockwise direction by the worm 85. The shifter fork 96 will thus be moved between positions shown by solid line 96 and dashed line 96C, so that the tyne 101B abuts against the lug 74B. The lower cam member 71 will thus be rotated in a clockwise direction so that the cam ramp surfaces 70 and 72 will be driven into mating engagement, and there will be no space between the lower collar 71 and the upper collar 63. Thus, the teeth 54 on the pinion 52 and the teeth 55 on the sleeve 56 will be driven into engagement under the influence of biasing spring 51. The oscillatory motion of the pinion 52 will therefore be transferred to the agitator shaft 30, so that the agitator 22 will oscillate in the tub 20.
When the main gear 83 is rotated in a counter-clockwise direction for the spin portion of the cycle, as shown in FIG. 8, the shifter fork 96 will be changed from the position shown in FIG. 5 to the position shown by the dashed line 96B, and the solid line 96A. The tyne 101A will abut the lug 74A imparting a limited counter-clockwise rotation to the lower cam member 71 as the eccentric 95 rotates, thereby disengaging the cam ramp surfaces 70 and 72 as shown in FIG. 7. The upper cam member 63 will thus be raised a height equal to the height of the ramp surface 72. The upper collar 63 abuts the washer 58 and thus the surface 57 on the pinion 52 so that the pinion 52 is also raised as identical height so that the teeth 54 and 55 are disengaged. The spring 51 is compressed slightly to allow this change in position.
During both clockwise and counter-clockwise rotation of the main drive gear 83, the tynes 101A and 101B extend a sufficient distance toward agitate shaft 30 to prevent complete disengagement of the shifter fork 96 away from the shaft.
During the spin portion of the cycle, spin basket 21 will be driven by a spin gear 81 having teeth 82 about the circumference which engage teeth 87 carried on a spin collar 107. Rotation of the spin collar 107 causes operation of the spin clutch and basket brake mechanism to effect rotation of the clothes basket 21. A delay means, shown generally at 91 in FIG. 3 is disposed in an annular groove 90 in the lower portion of the spin gear 81 to insure that the spin gear 81 will not be engaged to begin rotation of the basket 21 until a complete revolution of the main gear 83 in the counter-clockwise direction has occurred. One revolution is sufficient to insure that the shifter fork 96 will have changed from the position in FIG. 5 to the position in FIG. 8 and that the lower collar 71 will have rotated in the appropriate direction to disengage the teeth 54 and 55. The program control means through timer 15 provides the signal necessary to reverse the direction of the motor between the spin and agitate portions of the wash cycle. It will be understood that the scope of the cam ramp surfaces 70 and 72 is determined by the direction of the rotation of the main gear 83 during various portions of the wash cycle. The direction of the slope shown in the various figures is coordinated with a clockwise main gear rotation during the agitate portion of the cycle, and a counter-clockwise rotation of the main gear 83 during a spin portion of the cycle. If the directions were reversed, the slopes of the ramps 70 and 72 need only be reversed to accomplish engagement and disengagement.
Although various modifications and changes may be apparent to those skilled in the art, applicant intends to include within the patent warranted hereon all such changes and modifications as may reasonably and properly be included within the scope of applicant's contribution to the art. | A transmission shift mechanism for use in a vertical axis automatic washing machine having reversible rotary drive means has a drive gear on which is mounted an eccentric for translating rotary motion into oscillatory motion in a plane perpendicular to the washing machine axis. The oscillatory motion is transmitted to the agitator shaft of a washing machine by a rack and pinion. The pinion is rotatably mounted on the agitator shaft and has teeth on a lower surface thereof which engage teeth on an upper surface of a sleeve co-rotatable with the agitator shaft to form a jaw clutch for driving the agitator shaft from the rack and pinion. A shifter fork also connected to the eccentric operates cams to raise the pinion out of engagement with the sleeve to disengage the jaw clutch when the eccentric is rotating in a first direction, and returns the clutch teeth to engagement when the eccentric rotates in an opposite direction. | 3 |
FIELD OF THE INVENTION
This invention relates to the characterization of the quality and condition of reservoir rock during the extended exploration and further developmental drilling operations of a petroleum reservoir using data obtained from the pyrolysis of rock cuttings.
BACKGROUND OF THE INVENTION
Various methods have been employed for determining the porosity of petroleum-bearing reservoir rock. Such porosity measurements are used quantitatively in characterizing the reservoir rock for the purpose of determining hydrocarbon productivity and calculating reserves. One long-standing method is the direct analysis of cylindrical core samples that are taken during the drilling operation. Methods of analysis based on core samples have the advantage of being able to provide detailed and very accurate data of the reservoir quality at precisely known depths. The principal disadvantages of relying on core samples is that collecting the samples is both time-consuming and expensive, as is the processing of the core slabs to prepare samples for the one or more eventual analytical processes from which the data can be developed.
Down-hole "electric" or petrophysical logs are the most common means of assessing reservoir quality. The advantages of this technique are that the data is available immediately after the drilling of the well and the data can be obtained over the entire portion of the "open" well-bore. The disadvantages of this technique are that the data is not available until after the well is drilled, and this information cannot be used to assist in making drilling decisions. Measurement While Drilling ("MWD") or Logging While Drilling ("LWD") techniques partially overcome this deficiency; however, the cost for this service is very high and not all petrophysical tools can be utilized.
Another method for evaluating reservoir rock is based on the pyrolysis of rock cuttings that are carried to the surface during drilling operations by the drilling fluid, or "mud." Collection of rock cuttings associated with known depths is a well established procedure in petroleum drilling operations. Depth assignment to the cuttings is based on calculations which take into account drilling fluid circulation rate, hole geometry, fluid viscosity and weight, and other parameters. Collecting cuttings and assigning a depth to those cuttings are routine procedures during drilling operations.
The pyrolysis of reservoir rock and/or rock cuttings has been employed to determine the API gravity of oil and the composition of reservoir rock extracts. The pyrolytic method involves the heating of the sample in an inert atmosphere at an initial temperature of about 180° C. When the sample is inserted in the heated chamber, the light volatile hydrocarbons are removed and analyzed. The temperature is subsequently increased and heavier free oil is thermovaporized. Above approximately 400° C., hydrocarbons that have not been vaporized are thermally "cracked" to lighter hydrocarbons which are vaporized. The sample is heated to a maximum temperature of 600° C. in the inert atmosphere. The hydrocarbons released during these heating stages are quantified, as by a flame ionization detector ("FID"). If a complete analysis is required, the sample is contacted with a stream of oxygen or air at about 600° C. and the resulting CO 2 is analyzed by a thermal conduction detector ("TCD".)
Data plots of hydrocarbons released as a function of temperature can be produced on commercially available equipment. One such pyrolysis device and related analytical equipment is commercially available from the Institut Francais du Petrole through its distributor Vinci Technologies, (both of Rueil-Malmaison, France) under the trademark ROCK-EVAL. Another supplier of pyrolytic instrumentation is Humble Instruments & Services, Inc., of Humble, Tex.
As used in this specification and claims, the following terms have the meanings indicated:
HC means hydrocarbons.
ln means natural logarithm.
LV is the weight in milligrams of HC released per gram of rock at the static temperature condition of 180° C. (when the crucible is inserted into the pyrolytic chamber) prior to the temperature-programmed pyrolysis of the sample.
TD is the weight in milligrams of HC released per gram of rock at a temperature between 180° C. and T min ° C.
TC is the weight in mg of HC released per gram of rock at a temperature between T min ° C. and 600° C.
LV+TD+TC represents total HC vaporizing between 180°-600° C. A low total HC indicates rock of lower porosity or effective porosity. A low value can also indicate zones of water and/or gas.
POPI o is the value of the pyrolytic oil productivity index as calculated for a representative sample of crude oil of the type which is expected to be found in good quality reservoir rock in the region of the drilling and chosen as a standard.
T min (°C.) is the temperature at which HC volatization is at a minimum between the temperature of maximum HC volatization for TD and TC and is empirically determined for each sample. Alternatively, a temperature of 400° C. can be used for samples where there is no discernable minimum between TD and TC. The latter sample types generally have very low total HC yields.
Phi is the average porosity of the rock.
Sxo is the saturation of drilling mud filtrate and represents the amount of HC displaced by the filtrate, and therefore, movable HC.
Phi*Sxo vs depth plot--the area below the curve represents the proportion of porosity which contains movable HC.
Phi vs depth plot--the area between the Phi curve and the Phi*Sxo curve represents immovable HC, or tar.
Gamma--the naturally occurring gamma rays that are given off by various lithologies while measuring directly in the well bore by the prior art petrophysical tools and are reported in standard API (American Petroleum Institute) units.
Caliper--the measured diameter of the well bore taken at the time of running petrophysical logs.
Density porosity--the porosity calculated by prior art methods from the petrophysical bulk density tools using an assumed fluid and grain density.
Neutron porosity--the porosity measured by prior art methods from petrophysical neutron tools.
Deep resistivity--the resistivity measured by deep invasion (long spacing between source and receiver), lateral log or induction petrophysical tools which is used as a measurement of undisturbed formation resistivity.
Medium resistivity--the resistivity measured by medium invasion (medium spacing between source and receiver), lateral log or induction petrophysical tools which is used as a measurement of resistivity of the formation that has been flushed by mud filtrate from the drilling fluid.
Shallow resistivity--the resistivity measured by shallow invasion (short spacing between source and receiver), lateral log or induction petrophysical analytic techniques which is used as a measurement of the resistivity of the mud filtrate from the mud cake that forms on the interior of the well bore during drilling operations.
Neutron-density cross-plot porosity (N-D Phi)--the porosity determined from a common prior art method which compensates for the effects of lithologic and fluid changes that lead to inaccuracies in employing either density or neutron porosity measurements by themselves.
Core plug permeability--the permeability measured by prior art methods from cylindrical rock samples that are cut from cores taken from the drilling process that is reported in units of millidarcys (md).
In a typical pyrolytic data plot of oil-productive reservoir rock prepared in accordance with prior art methods, the first peak, which is detected when the sample is first placed in the pyrolysis oven at the initial temperature of 180° C. and before the temperature program begins, is from the volatile components still present in the sample after sample preparation. These will be referred to as the Light Volatile Hydrocarbons, reported in milligram per gram rock sample, and represented by LV or LVHC. As the temperature program proceeds, a plot of temperature vs. released hydrocarbons detected results in a curve that first increases from the starting point at 180° C., then gradually falls off to a minimum value in the vicinity of 400° C.±20° C. where thermocracking of the heavier petroleum components begins to occur. As thermocracking proceeds with increasing temperature, released hydrocarbons detected increase to a maximum and then fall off as the rock cutting sample reaches a maximum temperature of about 600° C. For any given sample, the minimum temperature point between the two peaks is referred to as T min . The area under the first peak between 180° C. (i.e., the starting point) and T min represents the total weight of hydrocarbons released in that temperature range, generally reported as milligrams per gram ("mg/g") of rock sample, and are referred to as the Thermally Distilled Hydrocarbons and represented as TD or TDHC. The area under the second peak between T min and 600° C. represents the total weight of hydrocarbons that are first thermally cracked before thermal distillation from the substrate and detection and are reported in mg/g of rock sample, and are referred to as the Thermally Cracked Hydrocarbons (TC or TCHC). Various techniques for analyzing the pyrolysis data represented by LVHC, TDHC and TCHC have been practiced in the art.
In the pyrolytic analysis process, small samples (e.g., ≦100 mg) of powdered rock are placed in a steel crucible. The crucible is placed in a furnace and the sample is heated in a stream of helium gas to an initial temperature of 180° C. After heating at 180° C. for about three minutes, the temperature is increased. The rate of increase in the temperature is about 25° C./min. or less, and preferably about 10° C./min, and progresses from 180° C. to about 600° C.
The helium gas carries hydrocarbon products released from the rock sample in the furnace to a detector which is sensitive to organic compounds. During the process, three types of events occur:
1) Hydrocarbons that can be volatilized at or below 180° C. are desorbed and detected while the temperature is held constant during the first 3 minutes of the procedure. These are called light volatile hydrocarbons (LVHC or LV).
2) At temperatures between 180° C. and about 400° C., thermal desorption of solvent extractable bitumen, or the light oil fraction, occurs. These are called thermally distilled hydrocarbons or "distillables" (TDHC or TD).
3) At temperatures above about 400° C., pyrolysis (cracking) of heavier hydrocarbons, or asphaltenes, occurs. The materials that thermally crack are called thermally cracked hydrocarbons or "pyrolyzables" (TCHC or TC).
These events give rise to three `peaks` on the initial instrument output (referred to as a pyrogram). The peak for the static 180° C. temperature is a standard output parameter of either the Vinci or Humble instruments. It is referred to as either S 1 or volatile total petroleum hydrocarbons (VTPH), respectively. In the present invention, the value will be referred to as LV, as described above. Data generated from the temperature programmed pyrolysis portion of the procedure is reprocessed manually by the operator to determine the quantity of hydrocarbons in milligrams per gram of sample above and below T min . This reprocessing is a trivial exercise for an experienced operator and can be accomplished routinely with either the Vinci or Humble instruments. The first peak above 180° C. represents the amount of thermally distillable hydrocarbons in the sample and is referred to as TD, the second peak above 180° represents the amount of pyrolyzables or thermally "cracked" hydrocarbons in the sample and is referred to as TC. In the case of lighter hydrocarbons or the analysis of oil samples directly for calibration, T min may not be discernable. In this case, if the sample analysis is repeatable at 400° C., the values of LV, TD, and TC employed in the method of the present invention are with respect to the specific temperature ranges defined above.
In other pyrolytic methods known to the prior art, measurement of released hydrocarbons was undertaken in the range up to 180° C. and identified as S 1 , or volatile total petroleum hydrocarbons (vTPH) while S 2 or pyrolyzable total petroleum hydrocarbon (pTPH) was the value associated with hydrocarbons released between 180° C. and 600° C.
The prior art methods for collecting and analyzing the data obtained by pyrolytic analysis have been found to be of limited value in making reliable determinations of the quality and condition of reservoir rock, particularly in regions of tar mats and occlusions.
It is often the case that tar mats are found between productive reservoir regions. Tar mats can be defined as high concentrations of bitumens enriched by asphaltenes. They form more or less continuous layers in the porous medium of the reservoir rock that can range from several feet to tens of feet in thickness and constitute barriers impermeable to the flow of crude oil.
Delays in obtaining information on the character and condition of reservoir rock can be especially costly when the drilling operation is being conducted "horizontally." As used hereafter in reference to well drilling operations, the term "horizontal" means wells bored outwardly from the nominally vertical well shaft or bore leading from the earth's surface. These horizontal wells are drilled for the purpose of exploring areas horizontally displaced from the vertical well shaft. Horizontal drilling is typically undertaken in an effort to increase the total footage of productive reservoir rock encountered by the well bore. Because of the potential for rapid changes in conditions from one area to another in the horizontal plane, it is desirable to characterize the reservoir rock as quickly as possible. Discontinuing drilling operations while awaiting analytical data can incur significant costs, and the costs of utilizing the MWD or LWD analytical techniques described above are also very high.
As will be apparent to one familiar with the costs involved, it would be particularly advantageous to be able to identify the presence of tar mats on something approaching a "real time" basis as the horizontal drilling operation proceeds. This information would permit the direction of the drill to be changed "on the fly" once the tar mat was detected.
It is therefore an object of this invention to provide an improved method, that is timely and cost efficient, for determining the quality and condition of reservoir rock during petroleum exploration drilling operations.
It is another object of the invention to provide a method for utilizing pyrolytic analysis data to differentiate between good and excellent quality reservoir rock.
It is also an object of the invention to provide an improved method of employing data from the pyrolytic analysis of rock cuttings for determining the character and quality of reservoir rock, including the existence of zones of low porosity rock and rock of low effective porosity.
It is a further object of the invention to provide a method from which information concerning the quality and condition of the reservoir rock can be quickly derived in the field and at the drilling site so that any changes in the direction of drilling can be made "on the fly" to maintain the position of the drill bit in the stratigraphic region of optimum production.
It is yet another object of the invention to provide a method by which the presence of tar mat in the vicinity of the drilling bit can be quickly and reliably determined by analysis of rock cuttings.
It is also an object of this invention to provide a reliable method for determining when the well bore has proceeded from oil-productive reservoir either structurally higher into a gas cap, if present, or downward below an oil-water contact.
SUMMARY OF THE INVENTION
The above objects and others are met by the method of the invention.
What we have found is data obtained from the pyrolytic analysis of rock cutting samples can be utilized to provide an extremely reliable indicator of the character and quality of reservoir rock. Data points have been identified using the method of the invention for delineating and distinguishing between (a) oil productive, (b) marginally oil productive/marginal reservoir rock and (c) tar-occluded/non-reservoir rock. These data points can be determined in real time during drilling operations, so that changes in the direction of horizontal boring can be made.
The method of the invention provides data that are at least as reliable as conventional log data based on time-consuming and relatively complex analytical techniques that are only available long after the directional drilling decisions have been made.
In the practice of the method of the invention the following expression is used to provide one or more data points:
ln(LV+TD+TC)×(TD÷TC)=POPI (I)
In the above expression, the term "ln(LV+TD+TC)" means the natural logarithm of the value and the term "POPI" is used as shorthand for Pyrolytic Oil Productivity Index. The term POPI is also used more broadly hereinafter as a reference to the method of the invention.
In one preferred embodiment of the invention, the method includes the sampling of reservoir rock cuttings from known depths and locations in an active drilling site, processing the cuttings to prepare the cuttings for analysis, obtaining data from the pyrolysis of each of these specially processed reservoir rock cutting samples, and producing a tabular or graphic representation or plot based on the sampling and pyrolytic data which representation indicates the character and quality of the reservoir rock with respect to its oil production potential.
More specifically, the method is directed to the steps of:
(a) collecting the rock cuttings from a first location;
(b) preparing the rock cuttings for pyrolytic analysis;
(c) subjecting the prepared rock cuttings to pyrolytic analysis to provide data corresponding to LV, TD and TC;
(d) graphically plotting the relationship expressed by the value of:
ln(LV+TD+TC)×(TD÷TC) versus measured depth for said first location;
(e) repeating said steps (a)-(d) above for rock cuttings obtained from a plurality of different locations displaced known distances from said first location to provide a graphic plot; and
(f) identifying the vertical intervals on said graphic plot corresponding to POPI values as determined by formula (I) of:
(i) 0 to about 1/2POPI o as tar-occluded and/or non-reservoir rock,
(ii) from 1/2POPI o to POPI o as marginal oil-producing reservoir rock and
(iii) above about POPI o as oil-producing reservoir rock.
If the depth is plotted horizontally, the POPI values corresponding to 0, 1/2POPI o and POPI o are entered as horizontal lines. The same data can be entered in tabular form. Graphic and tabular forms resulting from the practice of the method of the invention can be prepared manually or by a typical spreadsheet or graphical software on a suitably programmed general purpose computer.
The value of POPI o refers to the POPI value that has been determined using formula I for typical good quality reservoir rock containing oil of known composition from the region in which the drilling is proceeding. The composition or type of the oil in the region will have been determined previously and represents historical information from the original exploration of the region, e.g., via vertical drilling operations. Similarly, the characteristics of good quality reservoir rock will likewise have been determined relative to the region in which the horizontal drilling is planned or is proceeding. Thus, the value of POPI o as a standard for use in practicing the method of the invention can be determined before the horizontal drilling is commenced.
Oil composition is known to vary significantly in its specific gravity (gm/cc) or API gravity. This variance is due to differences in the relative quantities of the light molecular weight (typically hydrocarbons with less than 15 carbon atoms in each molecule), medium molecular weight (typically hydrocarbons with greater than 15 and less than 40 carbon atoms in each molecule), and high molecular weight components (typically hydrocarbons with greater than 40 carbon atoms and non-hydrocarbons with molecular weights between 500 and 1500 gm/mole). The specifics of these variations are not important to this invention. However, as will be understood by one of ordinary skill in the art, it is important to determine the value of POPI o .
Determining Value of Standard--POPI o
The value of POPI o can be determined from rock samples from an oil-filled reservoir, similar to the drilling target, that are of good reservoir quality, or from a sample of oil that is similar to the expected composition of the well's targeted zone. In the case where similar rock samples are used, steps a-c as previously described are employed to determine the value of POPI o . Where an oil sample is used to determine POPI o , the following procedure is followed:
1) To 1 cc of the oil sample, add 9 cc of a suitable solvent, such as methylene chloride, dimethyl sulfide or other suitable solvent that will completely dissolve the oil sample and that is readily evaporated at 60° C. Characteristics of solvents?!
2) Prepare 9 steel crucibles with approximately 100 mg of clear silica gel.
3) Apply to the silica gel, using an accurate syringe, three samples each of the solution of the oil in solvent in quantities of 10, 20, and 30 micro-liters.
4) Dry the samples at 60° C. in a vacuum oven for 4 hours.
5) Subject the samples to pyrolytic analysis, using 100 milligrams as the required input sample size for the instrument, to provide data corresponding to LV, TD, and TC.
6) Utilize standard spreadsheet and graphics software to input the data and prepare a plot with the y-parameter being the POPI value and the x-parameter being the sum of total hydrocarbons (LV+TD+TC).
7) Select the range for the value of POPI o from the chart where the value of total hydrocarbons is between 4-6 milligrams per gram of sample.
This value is a fairly typical value of the residual staining that remains after sample preparation from oils that are less than 42 API gravity. Oils of higher API gravity may require the use of lesser values for total hydrocarbons, since the residual hydrocarbon staining may be significantly lower due to evaporation of the light components and lower amounts of the medium and heavy components. Evaluation of good quality and productive reservoir rock is the preferred means of determining the value of POPI o for reservoirs yielding oil having an API greater than 4Z.
Sample Preparation
In accordance with methods known to the prior art, cutting samples can conveniently be collected from the shale shaker on the drill rig. The wet cuttings are sieved to obtain about 1-2 gms of particles between 40/120 mesh.
In accordance with the method of the invention, the sieved samples are rinsed with water and then with an aqueous solution of hydrochloric acid at a pH of about 5 to remove any water-soluble polymer components carried over from the drilling mud. The washed cuttings are dried in a vacuum oven at about 60° C. (approximately one hour.)
The dry cuttings are ground, e.g., using a mortar and pestle, and can now be processed in the same manner as ground core samples for pyrolytic analysis in any one of the known instruments.
In the interests of reducing the time between sample collection and the generation of the graphic plot, the drying step can be expedited by use of a mechanical shaker or other means that will agitate or tumble the rock fragments comprising the cutting sample and expose the individual surfaces. The ability to rapidly process the samples is a significant factor since under some conditions up to a 100 feet interval can be drilled horizontally during a two-hour test and data processing period.
Using known methods and apparatus the prepared reservoir rock sample is subjected to pyrolytic analysis. The data discussed below were obtained using the instrument sold by IFP under the trademark ROCK-EVAL in combination with a general purpose computer. The computer was programmed (using existing software provided by the manufacturer) to calculate the quantitative values for the hydrocarbons released from the prepared samples corresponding to the values of SI (or vTPH or LV) and S 2 , which is then reprocessed by the operator to determine the values corresponding to TD and TC. The data values of the consecutive analyses were transferred to a spreadsheet for further manipulation and evaluation.
Having obtained the quantitative values for LV, TD, and TC for a given sample, the method of the invention is used to calculate the following parameter for a sample "X":
ln(LV.sub.x +TD.sub.x +TC.sub.x)×(TD.sub.x ÷TC.sub.x)=POPI.sub.x (II)
In a preferred embodiment, this data point is entered on a graphical plot of POPI versus the measured depth corresponding to the location of that sample to provide a permanent record. Alternatively, the data can be entered in tabular form, e.g., on a chart. The data can also be stored in the memory device of a preprogrammed general purpose computer for the purpose of generating graphic and/or tabular data outputs after analysis of all samples has been completed.
As will be understood, the process is repeated for cutting samples obtained from adjacent locations. The number of samples collected and analyzed, and their relative proximity, will determine the precision of the data obtained and the eventual graphic plot. A graphic plot of the data points provides a convenient mode for visualizing the regions demarked by the POPI values derived from formula (I).
What we have found is that certain values of the POPI can be used to reliably indicate the condition and quality of reservoir rock. The values are as follows:
A POPI greater than about POPI o , indicates oil-producing reservoir rock;
a POPI between 0 and 1/2POPI o indicates tar-occluded or non-reservoir rock; and
a POPI between about 1/2 POPI o and POPI o indicates marginally oil-producing reservoir rock.
The unique reliability of the POPI is based on the fact that it combines different aspects of pyrolysis output parameters into a single number that has a practical utility in assessing reservoir quality. The first term in the equation, ln(LV+TD+TC), reflects the total quantity of hydrocarbons remaining in a rock sample after the effects of in-reservoir alteration, hydrocarbon flushing by the drilling fluid, evaporation of the light components, and losses due to cleaning and processing the sample, as described above. The second term, TD/TC, reflects the ratio of the quantity of light and heavy components in a sample, or the "quality" of the oil. The proximity of this number to the values of hydrocarbon fluids actually produced indicates whether significant alterations to the composition of the fluid have occurred. Thus, when the POPI method yields values that approximate, or are close to the value of POPI o , it is consistent with: (1) a favorable reservoir quality that reflects the migration of petroleum migration into the rock, and (2) a alteration effects that are generally associated with a variety of reservoir conditions that result in poorer oil productivity.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is the typical instrument output or pyrogram (prior to reprocessing the data) from an oil sample, indicating the areas associated with the data used to calculate the POPI values in accordance with formula (I).
FIGS. 2A 2B and 2C are plots of typical data obtained from the pyrolytic analysis of reservoir rock indicating the regions associated with the values TD and TC for tar-occluded reservoir rock, marginally productive reservoir rock, and oil productive reservoir rock, respectively.
FIG. 3 is a comparative graphic plot of data obtained by the method of the present invention and petrophysical log data obtained by prior art methods with interpreted zones indicated for the quality of the reservoir rock.
FIG. 4 is a graphic cross-plot of total hydrocarbons (LV+TD+TC) versus the Pyrolytic Oil-Productivity Index (POPI) used to determine the value of POPI o .
FIG. 5 is a cross-plot of Phi*Sxo versus POPI for data obtained from the well in the example shown in FIG. 4.
FIG. 6 is a comparative graphic plot of POPI and neutron-density cross-plot porosity (N-D Phi) versus depth for a well exhibiting both gas-oil and oil-water contacts.
FIG. 7 is a comparative graphic plot of POPI and core plug permeability versus depth.
FIG. 8 is a comparative graphic plot of depth profiles for pyrolytic data and petrophysical log data obtained by prior art methods for a well exhibiting both gas-oil and oil-water contacts.
DETAILED DESCRIPTION OF THE INVENTION
The graphical plot of the typical output pyrogram obtained by employing theRock-Eval instrumentation in accordance with methods well-known in the prior art is shown in FIG. 1. The curve represents the flame ionization detector's (FID's) response for the initial static temperature conditions and the later temperature-programmed pyrolysis of the sample. The area under the curve represents the relative values or quantities of light volatile hydrocarbons (LV), thermally distilled hydrocarbons (TD) and thermally cracked hydrocarbons (TC), which values are used to calculate toPOPI. The value of LV is obtained directly from the instruments sold by Humble and Vinci with no further reprocessing, while the values of TD and TC require additional processing of the initial output data by the operator.
Reprocessed graphic plots of hydrocarbons versus temperature of typical quantitative analyses of rock samples from a well which are indicative of tar-occluded, marginal, and oil-productive reservoir rock are shown in FIGS. 2A-2C. The plots represent straight-forward manipulations of data obtained employing the ROCK-EVAL instrumentation in accordance with methods well-known in the prior art.
As is indicated on the plots, FIG. 2A represents tar-occluded rock, 2B marginally productive reservoir rock and 2C oil productive reservoir rock.In the plots of FIGS. 2A-2C, the TD peak corresponds to the thermovaporization of approximately C18-C40 hydrocarbons present in the reservoir rock sample, and the TC peak mainly corresponds to the thermovaporization and cracking of approximately C40 and greater hydrocarbons, including the cracking of the resins and asphaltenes.
As noted above, the expression Pyrolytic Oil-Productivity Index, or POPI, is determined as follows:
POPI=ln(LV+TD+TC)×(TD÷TC). (I)
By employing the values of LV, TD and TC obtained for rock samples from a horizontal well and the equation (I), the graphic plot of FIG. 3A was prepared in accordance with the method of the invention.
In FIGS. 3A and 3B, the abscissa is the measured depth in feet and the ordinate values are various pyrolytic and petrophysical parameters. The plots of FIGS. 3A and 3B provide a comparison of predicted reservoir performance for a horizontal well by petrophysical logs (3B) and the Pyrolytic Oil-Productivity Index (3A). The POPI interpretation identifies the same changes in reservoir quality that are interpreted from the well logs as plotted in FIG. 3B. The minor differences that are present are a thin marginal bed at 8480 ft., a thin tar-occluded bed at 9940 ft., and the shifting of some oil-productive to marginally oil-productive boundaries to deeper apparent depths. These shifted boundaries resulted from the mixing of cuttings and can be prevented by stopping to circulate "bottoms-up" cuttings during drilling operations. The horizontal lines at POPI values of about 1/2 POPI o and POPI o demark the following regions: oil-productive rock (above POPI o ), marginally oil-productiverock (between about 1/2POPI o , and POPI o ), and tar-occluded and/ornon-reservoir rock (between about 1/2POPI o and zero.)
The value of POPI o can be obtained by subjecting an oil of a composition that is similar to the expected oil in the reservoir to the procedure set forth in steps 1-7 of the method as described above. FIG. 4 is a cross-plot of the POPI and total hydrocarbons showing the separate trends that are characteristic three typical oils of two distinct different oil-types. From these data, the POPI o (the POPI that is expected for a sample from a typical good quality oil reservoir with a given oil type) can be estimated as the value of POPI that corresponds to a total hydrocarbon yield of around 4-6 mg/g of rock.
Again, with reference to FIGS. 3A and 3B, the reliability of the results ofthe pyrolytic analysis method of the invention is confirmed by comparison with petrophysical data for the same region. The data were obtained and analyzed for Region "A" in drilling a horizontal oil well which penetratedpartially occluded/partially productive and oil-productive portions of a tar mat. The results from Region "A" confirm the strong correspondence between the pyrolytic and petrophysical data. From 8,460 ft. to 8,970 ft.,the formation was dominated by a completely tar-occluded region and some marginal regions, as is evident from the combination of high porosity (Phi), high total HCs (LV+TD+TC), and correspondingly low TD/TC, Phi*Sxo, and POPI plots. While the lower porosity areas do contain tar, they are not completely occluded because the low porosity inhibits filling the porespace. Both the TD/TC and POPI plots differentiate the oil-productive and the tar-occluded/non-reservoir portions of the formation.
The POPI method is also utilized to effectively differentiate between oil-productive and marginal reservoir quality. For example, the marginal reservoir quality zone from 9,775 to 9,925 ft. is distinguished from oil-productive reservoir by the POPI but not by the TD/TC ratio. Note thatthe reservoir quality boundaries are displaced to greater depths in this area. This shifting is due to drilling ahead and not stopping periodicallyto circulate "bottoms-up." The POPI also does a better job of identifying non-reservoir rock that is tight but contains staining of normal hydrocarbons. This is evident in the low porosity zone form 9,200 to 9,500ft., where the TD/TC ratio indicates marginal quality reservoir, but the POPI clearly identifies this region as non-reservoir rock. Also, Phi*Sxo can be especially misleading in lower permeable reservoir rock. This is caused by inefficient mud-cake formation in the well bore. Because mud-cake does not form as quickly over lower permeability rock, the mud filtrate water can invade the formation over a much longer time period, and thus, invade farther. This produces an exaggerated assessment of the moveability of hydrocarbons (as is seen in the intervals from ˜8,600ft to 8,700 ft., ˜8,875 to 8,925, and from ˜9,075 ft. to 9,200 ft (FIG. 3) that is overcome by the POPI method.
The general correspondence between the reservoir quality as determined by the POPI and prior at methods from FIG. 3, is shown in FIG. 5 by plotting Phi*Sxo versus POPI. While there is some scatter in the data, this is typical of the scatter found when employing cross-plot graphics with petrophysical data. The importance of this general relationship is that relative differences seen in the POPI have significance in determining reservoir performance.
Moreover, a detailed analysis of productive formation elsewhere shows that the POPI can also be used to differentiate between good and excellent reservoirs. FIG. 6 is a plot of measured depth versus neutron density cross-plot porosity, (N-D Phi), and POPI, in which the reservoir was characterized based on the combination of the pyrolytic and petrophysical data. The trend in increasing POPI from approximately 10,433 ft. to 10,447ft. corresponds to porosity that increases from about 8% to 14%.
An increase of 6% in porosity corresponds to a substantial improvement in reservoir performance, establishing that the POPI method has potential forassessing differences between good and excellent reservoirs prior to running well logs.
The same correspondence between the POPI and reservoir performance is observed when comparing it to core plug permeability. FIG. 7 shows that variations in the POPI and core plug permeability mirror each other and that the highest values of POPI correspond to permeability over 100 millidarcys ("md") and lowest values correspond to permeability less than 10 md. Thus, by a variety of different petrophysical measurements, the POPI yields the same interpretation of reservoir performance, but in a timely and cost efficient manner not previously available to the art. Using the method of the invention to optimize the value of the POPI duringhorizontal drilling greatly increases the likelihood of staying within the most productive portion of the reservoir. The use of the method leads to greater productivity for individual wells by substantially increasing the length of the well path in that part of the reservoir exhibiting optimum conditions.
FIG. 8 is a comparison of POPI, TD, and TC depth profiles to standard petrophysical data for a well with gas-oil and oil-water contacts. In thisplot, the OWC as interpreted from well logs has been obscured by a dramaticchange in the formation's water salinity from below the oil column, This has been caused by a later incursion (post oil migration) of fresh meteoric ground water that has been well documented by laboratory analysesfrom wells in the area. The problem of predicting the type of formation fluids (oil or water) in this geographical area of operations is common.
FIGS. 7 and 8 also demonstrate how the data can be used to determine when the drill-bit has moved downward structurally through an oil-water contact(OWC). When this situation occurs, the value for POPI becomes negative. This transition can reliably be interpreted where at least poor quality oil-productive reservoir is present. A gas-oil contact (GOC) can also be interpreted in a similar manner, except that the change is from low positive or negative numbers to values that are indicative of oil-productivity as one moves downward through the reservoir. These are interpretations that can routinely be made, even by well-site geologists with limited experience. In these cases, the examination of drill cutting samples would assist in confirming that major lithologic changes were not responsible for differences in the POPI.
The plot of FIG. 8 shows how the POPI can yield a more accurate interpretation of the oil-productive reservoir than the petrophysical tools. With respect to the particular site, it was well known that ground water flow through oil-productive reservoirs had occurred over the last 50,000 years. This relatively fresh water had displaced the original, relatively salty, low resistivity water that was present during marine deposition of the sandstone reservoirs. These historical events obscured the resistivity response to the OWC and now show no discernible differencein the invasion profile above and below the OWC. (Invasion profile refers to the separation of the data curves from the shallow, medium, and deep radius of investigation resistivity tools and is more obvious between 10,420 and 10,462 ft.). In this case, the use of expensive logging-while-drilling ("LWD") tools would not have correctly interpreted the lack of oil productivity between 10,450 and 10,462 ft.
The close relationship between the petrophysical and POPI data plots confirms the validity of the use of the method of the invention in predicting reservoir performance, particularly where tar mats and reservoir fluid contacts are encountered. Furthermore, the ability to effectively differentiate more subtle changes in reservoir performance from the POPI data has been established empirically. The method of the invention can be used more cost-effectively than prior methods and data asa basis for directing the forward movement of the drill bit during continuing horizontal drilling operations. Analytical utilization of all of the data generated from the POPI method can be used to delineate not only tar-occluded and non-tar-occluded sections, but also to indicate low porosity or low effective porosity zones.
More importantly, the method of the invention also differentiates between good and excellent reservoir rock. These distinctions are important indicators of changes in stratigraphic conditions within a reservoir and can be used to maintain the position of the drill bit in the "sweet spot" of the target reservoir.
The limitations of prior art methods in assessing the effects of the invasion of mud filtrate in low permeability zones are overcome by the POPI method of the invention. In cases where the low permeability is due to a generally lower porosity zone, the poorer reservoir is evident from lower total hydrocarbon value for LV+TD+TC and yields a lower POPI value. In the case of lower permeability due to substantial tar occlusion, the TD/TC ratio lowers the POPI value. Conversely, the interpretation of a lower POPI value can be made more conclusive by referring to the values ofthe POPI component variables: low total hydrocarbons (LV+TD+TC) point to lower porosity or effective porosity in the reservoir, while low TD/TC ratios indicate tar occlusion or other oil degradation processes.
From the standpoint of operations, the method of the invention can be practiced on site at the location of the drilling rig. This is an important factor in minimizing the turn-around time from collection of cutting samples to generation and interpretation of the data from the pyrolytic analysis of those samples. An average turn-around time of two hours for continuous operations has been achieved using standard equipment. A reduction in sample preparation time, as by the use of specialized vacuum dryers, can lead to further substantial reductions in the turn-around time. This makes the method of the invention an invaluabletool for predicting reservoir performance when the data are needed, that is, while the well is still being drilled.
A factor that can affect the accuracy of the method of the invention for predicting the quality and condition of the reservoir rock at a specified depth is a caving or sloughing of the drill cuttings. The effect of cavings on POPI is the apparent shifting of some boundaries of reservoir performance deeper in the well as seen in FIG. 3. In analyzing the data, it will be understood that a change in reservoir character from oil-productive to tar-occluded/non-reservoir quality may be partially masked by cavings until representative cuttings are collected for an interval, either by stopping to circulate "bottoms up" when an important change in reservoir character is detected, or by drilling ahead until a sufficient thickness of similar quality reservoir has been drilled to result in a more homogenous sample. The second practice is discouraged because it decreases the value of the information that is obtained prior to getting representative cuttings, thereby, decreasing the resolution of the data.
In any event, the art has developed methods for determining the extent and effect of cavings on depth calculations and these techniques can be used to correct data entries associated with apparent measured depth plots or tables in practicing the present invention.
As noted above, the values for the LV, TD, and TC parameters were determined on pyrolytic instrumentation known as Rock-Eval®. Data obtained from different instrumentation may not be identical. This is because the furnace geometry, design of the heating mechanism and the efficiency of heat transfer, and crucible geometry all play a role in quantifying the LV, TD, and TC parameters. However, the fundamental relationship on which the POPI method is based remains valid. Since the POPI may be somewhat different for the same sample if different pyrolysis instrumentation is used, the limits for characterizing the reservoir rock may vary. The methodology described above will enable one of ordinary skill in the art to determine the equivalent parameters without departing from the scope and spirit of the invention.
There are a variety of ways in which the teachings and spirit of this invention may be practiced which include the steps of sample preparation, instrument input parameters, and the way that the output data are reported. For example, an experienced worker in the field of the present art, could select different temperature cut-off values, that in turn couldbe used to develop new indices that combine components that relate to the quantity and nature of the hydrocarbons present in rock samples. Such variations in methodology will be understood to fall within the scope of the present invention and, in fact, might be necessary for the applicationof the technique to specific field conditions. | Data from the pyrolytic analysis of rock samples obtained from drilling operations in an existing oil field are used to characterize the quality and condition of reservoir rock by comparison of the values of an index for the unknown reservoir rock samples with the value of the index for a known type and quality of petroleum reservoir rock sample, the index being denominated Pyrolytic Oil Productivity Index ("POPI") and defined by the expression:
ln(LV+TD+TC)×(TD÷TC)=POPI (I),
where the terms of the equation are determined empirically and the resulting POPI values can be used to direct horizontal drilling operations in real time to optimize the position of the drilling bit in the reservoir. | 4 |
FIELD OF THE INVENTION
The invention relates to the field of batteries and printed circuit boards. More particularly, the present invention relates to thin film batteries disposed within thin film printed circuits for localized powering of electronic devices.
BACKGROUND OF THE INVENTION
Microsatellites and nanosatellites have been developed for use in space. The development and use of small space systems is likely to increase with new technologies. In U.S. Pat. No. 6,300,158 titled Integrated Solar Power Module, a method is described for producing thin film solar cells that are integrated with a multilayer printed wiring board and power processing electronics. In U.S. Pat. No. 6,127,621 a novel architecture for a satellite power system is described using various electronic devices such as power regulators. This architecture decentralizes the generation, distribution, and storage of electrical energy on the spacecraft using many individual electronic chargers and regulators. Traditionally, the battery is a separate component on the spacecraft. The battery is typically composed of a number of individual battery cells connected in a series to provide the necessary voltage to the bus. The batteries and individual battery cells may also be connected in parallel to provide the necessary curt to the bus. In the power system, each individual battery cell is connected to a main power distribution bus with a respective individual DC-DC converter that performs the function of providing current to the battery from the bus when sufficient energy is available from attached power sources, and, to supply power from the battery to the bus when the power from the power sources is insufficient to supply power to a load connected to the bus.
Typically, power distribution, power processing, and load electronics are mounted on rigid or flexible printed wiring boards with the battery located in a remote and completely separate battery housing structure. The separation of the battery from the powered electronics disadvantageously requires the use of macroscale power bus systems.
The battery cells of a battery are usually contained in a metal or plastic container with two terminals. The power electronics are usually remotely mounted on rigid or flexible printed wiring boards. In some cases, the battery cells have been mounted on printed wiring boards to provide some capability to store electrical energy locally to the power electronics. However, the battery cells only supplies power, and needs charging and discharge electronics, and hence, additional electronic power devices are used with the battery cells. It is difficult to meet the dual function requirement for small satellites with existing battery cell technology because a battery typically does not have self-contained electronic chargers and regulators disadvantageously requiring the remote, separate, and discrete electronic devices. New thin film batteries have been made using solid electrolytes. This thin film battery technology has the advantage of utilizing spray or vacuum deposition processes. However, such thin film batteries are stand-alone devices and require distal power routing to electronics devices. These and other disadvantages are solved or reduced using the invention.
SUMMARY OF THE INVENTION
An object of the invention is to provide a battery module having a thin film battery proximal to electronic devices.
Another object of the invention is to provide a battery module integrated with electronic devices.
Yet another object of the invention is to provide a battery module integrated with electronic devices using a thin film multilayer printed circuit board.
Still another object of the invention is to embedded a thin film battery in a thin film multilayer printer circuit board.
A further object of the invention is to provide a thin film battery module with an embedded thin film battery integrated with a thin film printed circuit board.
Yet a further object of the invention is to provide a thin film battery module with an embedded thin film battery integrated with a thin film printed circuit board on which electronic devices can be disposed for controlling the operation of the thin film battery.
The invention is directed to an integrated thin film battery module having an integrated circuit board. The integrated thin film battery module includes a flexible printed circuit, a thin film battery cell, and associated power regulating electronics. The flexible printed circuit can be used as the substrate for a thin film battery cell on one side, and for the mounting of electronic devices on the bottom side. In the preferred form, the module can be so integrated as to have effectively two printed circuit boards on each side of an embedded thin film battery for providing a top and bottom printed circuit board surface for respectively supporting top and bottom electronic devices.
The thin film printed circuit is preferably fabricated on a substrate composed of polyimide or other flexible polymer insulating materials. Copper or other suitable metal conductor traces are deposited on the polymer material over which another layer of polymer material is deposited. This layer deposition process is repeated to fabricate multilayer flexible printed circuit boards with embedded conductor traces. In a series of conventional processing steps, a thin film battery cell is deposited on the flexible circuit board. Preferably, a second multilayer flexible printed circuit board is then deposited on the battery cell so as to enclose and embed the battery cell material. Finally, discrete electronic devices are to be mounted on the top and bottom sides of the module as a self contained unit.
The thin film battery module can be manufactured using conventional thin film processes. The module is well suited for integrating load electronics and power processing DC-DC converters onto a flexible printed wiring board that also contains one or more thin film battery cells. The module can have commercial and space vacuum applications. These and other advantages will become more apparent from the following detailed description of the preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of an integrated thin film battery and circuit module.
FIG. 2 is a flow diagram of an integrated thin film battery and circuit module manufacturing process.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An embodiment of the invention is described with reference to the figures using reference designations as shown in the figures. Referring to FIG. 1 , an integrated thin film battery and circuit module includes a thin film battery cell that comprises an anode collector, an anode, an electrolyte, a cathode, and a cathode collector. The thin film battery can be deposited upon a polyimide substrate. The battery materials can be deposited through a shadow mask to obtain a specific cell pattern on the polyimide substrate. The polyimide substrate can be formed as a multilayer printed circuit board. The flexible circuit board is fabricated using multiple polyimide layers along with necessary embedded horizontally extending conductor traces and vertical extending feedthrough traces.
In the preferred form, one or more battery cells are disposed between two flexible printed circuits, a top circuit having top circuit conductor traces and a bottom circuit having bottom circuit conductor traces. The flexible circuits are made by repetitively alternately depositing polyimide layers and patterned horizontal conductor traces. After forming the bottom flexible printed circuit, thin film battery cell layers are deposited on the bottom flexible printed circuit through a shadow mask. The shadow mask defines the battery pattern and prevents the deposition of battery cell material in areas where feedthrough holes will be drilled through the flex printed circuit. After depositing the bottom flexible circuit and the battery layers, the top flexible circuit with embedded top conductor traces is deposited over the battery layers, as an integrated module. The feedthroughs are drilled and copper is deposited in the feedthroughs for forming vertical running conductor traces. The vertical extending copper feed through traces are connected to the horizontally extending conductor traces. The embedded vertical feedthrough and horizontal traces can be formed for interconnecting top and bottom electronic devices to the thin film battery cells. The vertical and horizontal traces are used to make electrical connections to the battery cell cathode and anode collectors through negative and positive terminals, as well as making electrical contact to the top and bottom electronic devices.
Referring to FIGS. 1 and 2 , and more particularly to FIG. 2 , a manufacturing process is used for forming the integrated battery and circuit module using conventional thin film processes. The process is characterized as having three repetitive process loops for forming a plurality of layers of the bottom printed circuit, for forming a plurality of layers of a plurality of battery cells of the battery, and for forming a plurality of layers of the top printed circuit. At the start, a release structure, such as a sheet of Mylar, is used as a temporary support structure on which is firstly deposited the first circuit layer. A first layer of polyimide is deposited on the release structure. Then a shadow mask is used to deposit bottom circuit traces on the first layer polyimide. Another layer of insulating polyimide is deposited on the bottom circuit traces. Consecutive layers of insulating polyimide and patterned conductor traces are deposited until all of the layers of the first bottom circuit are fully deposited. The thin film battery is then deposited on the bottom circuit layer using a shadow mask. Patterned metal is deposited for forming the cathode collector and then cathode. The electrolyte is deposited over the cathode. The anode and then the anode collector are deposited over electrolyte thereby forming a first one of a plurality of thin film battery cells. The process for each cell is repeated until all of the cells are deposited, only the first of which is shown for convenience. A top printed circuit is then formed over the thin film battery. A plurality of polyimide layers with alternating conductor trace layers are deposited in sequence using shadow masks. When all of the layers are deposited, the last layer is a top conductor trace layer deposited on the top last polyimide layer surface of the thin film battery module.
After forming the bottom printed circuit, middle thin film battery, and top printed circuit with a top conductor trace layer, the thin film battery module is then released from the release structure. The module is flipped up side down, and a bottom trace layer is deposited on the now exposed bottom surface of the thin film battery module, so as to complete the formation of all of the horizontal conductor traces. Next, vertical feedthroughs are drilled through the printed circuit layers of the module and copper feedthrough traces are deposited into the drilled feedthroughs, thereby completing the formation of all of the conductive vertical and horizontal traces that are interconnected as horizontally extending conductor traces and vertically extending feedthrough traces. Specific feedthrough traces connected to the middle thin film battery are designated as positive and negative terminals of the battery. Next, and finally, top and bottom devices, are bonded to respectively top and bottom surfaces of the thin film battery modules, and electrically bonded to top and bottom surface conductor traces so as to electrically interconnect the top and bottom devices to the network of traces as well as to the thin film battery. The top and bottom devices are heat-producing devices, but are preferably electronic devices, such as voltage regulation and charging electronic devices.
The present invention is directed to an integrated thin film battery integrated with thin film printed circuit boards formed as flexible layers. Various insulating and conductive materials can be use to form the top and bottom insulating layers and conductive traces, though polyimide and copper are the preferred materials. Those skilled in the art can make enhancements, improvements, and modifications to the invention, and these enhancements, improvements, and modifications may nonetheless fall within the spirit and scope of the following claims. | One or more thin film battery cells are embedded in a multilayer thin film flexible circuit board supporting electronic devices, such as power regulators, for forming an integrated battery and circuit module. The module can be made using conventional thin film processes. The module is well suited for applications where size and space limitations, such as on spacecraft or credit cards, require the use of ultra thin power sources integrated with respective electronic devices and printed circuits. | 7 |
TECHNICAL FIELD OF THE INVENTION
The present invention relates generally to mechanical hand held tools, and more specifically to multi-function pocket tools which include a jaw-type tool and other selected tools.
BACKGROUND OF THE INVENTION
Multi-function tools are well known in the art, and typically are designed around a jaw-type tool such as gripping tools (pliers and the like) or cutting tools (scissors, shears, pruning tools, etc). These jaw-type tools may or may not be folded or retracted into the handles of the tool, but utilize both handles for operation. And, a seemingly endless list of additional tools such as screw drivers, knife blades, can openers, cork screws, files, awls, etc. are then designed to be incorporated into the handles so that a wide variety of useful tools can be combined into one compact multi-function tool. It should be noted that “blades” and “tools” may be used interchangeably throughout this disclosure, to refer generally to any of the tools listed above that are attached to only one of the handles, and may include a pair of scissors or other hinged tools that can be extracted out of one handle.
Multi-function tools in which the jaw-type tool does not retract or fold into the handles have a significant disadvantage in the size of the overall tool. In order to comfortably use the tool, and be able to apply any reasonable gripping force in the case of pliers and the like, the handles must be long enough to be gripped by the hand. This makes a non-retractable, non-folding tool too long to fit in a pocket, and uncomfortably long to fit in a sheath and be worn on a belt around the waist of the user. Additionally, in the case of cutting tools (scissors, pruning tools, shears, etc), the sharp edges are also exposed and can inadvertently snag or cut people, clothing, etc., perhaps even without the knowledge of the person carrying the tool.
Multi-function tools that retract the jaw-type tool into the handles, as disclosed in U.S. Pat. No. 5,142,721 of Sessions, et al. overcome the tool length issue described in that when the jaw-type tool is retracted the multi-function tool is short enough to be carried comfortably in a pocket or in a sheath, and offers the user and his surroundings protection from sharp surfaces if the jaw-type tool is designed for cutting. This design of tool has significant limitations as well, however. Some of the noted disadvantages include complexity in construction of the tool, somewhat reduced strength of the jaw-type tool (particularly important in gripping tools such as pliers), and a very confined area for extracting other tools out from the cavities within the handles due to the fact that the handles only open a few degrees about their dependent hinged attachment to the tang end of the jaw-type tool. Finally, this type of tool typically maintains a gap between the two handles when the jaw-type tool is retracted into the handle and all other tools are stored within their respective cavities. This is disadvantageous for storage in a pocket, as it becomes a “trap” for loose change, keys, lint, and any other items that may be simultaneously stored in the pocket, so that when the tool is retrieved from the pocket these items are also removed, and can fall from the tool and potentially be lost.
Multi-function tools that fold the jaw-type tool into the handles for storage as disclosed in U.S. Pat. No. 5,743,582 of Rivera overcome the problems associated with both other types of tools previously described, but present a different limitation in that when the jaw-type tool is extended, the handles cannot open the jaw-type tool if any significant force is exerted on the outside of the jaws, as the handles of the tool will start to collapse for storage. This is not particularly significant for cutting tools, but may be a constraint for gripping tools if they are to be used for expanding springs and the like.
One limitation that may be associated with any of these three types of tools is that each of the handles is typically manufactured from a single piece of metal, and is formed generally into a channel shape. And, although this can add structural strength, it becomes significantly more difficult to manufacture the tools with little or no lateral clearance or sideways “play” so that an extended blade or tool is held firmly when encountering forces that act perpendicular to the longitudinal plane, i.e. acting against the side of tool, because of the one-piece construction. The walls of the handle cannot be brought closer together to take up any clearance or “play” without bending the channel itself. Any excess clearance also affects the feel of the tool, potentially giving the user a less than optimal confidence in the tool. Consequently, the thickness of the tools and any interspersed spacers must be precise both individually and cumulatively so as to precisely fill the space between the channel walls.
Another limitation generally associated with any of these types of tools, and with folding knives in general, resides in the blade lock mechanism. Known locking mechanisms used to lock tools in the fully extended position, of which there are many designs, always have a substantial amount of material and numerous parts (lock, spring, and connecting parts) located within the typical storage cavity of the tool handle. In other words, most or all of the blade lock mechanism is contained between the two pivot pins located at the two opposite ends of the tool handle, and generally between the outer side walls of the tool handle. This increases the overall size of the tool, which is undesirable.
It is also desired to avoid clumping, the phenomenon of when one blade is selected for extension, the other tools nearby rotate with the selected tool due to frictional forces holding the tools and interspersed spacers together within the channel of the handle.
Accordingly, there is a need in the art for a multi-function tool that can take advantage of the benefits of the folding type tool, but which can also overcome the noted limitations associated with opening the jaws of previously available tools under force. A need also exists for a handle that provides a greater dimensional tolerance range of the tools in a multi-function tool yet still provides a solid feeling tool that minimizes the amount of lateral “play” associated with the tool, and that facilitates optimal ways of assembling such a tool. A need for removing most or all of the blade locking mechanism from between the two pivot pins of a tool handle yet still providing a secure blade lock mechanism also exists. It is to these ends that the folding multi-function tool of the present invention is primarily directed.
SUMMARY OF THE INVENTION
The present invention provides a folding multi-function tool which overcomes some of the aforementioned limitations of the prior art, and which includes features that may be used individually or in combination to address those limitations, as desired. A multi-function tool that is an exemplary embodiment of one aspect of the present invention includes a pair of jaw handles each pivotally connected to an end of one of the two jaws, scissors blades, or the like, of a jaw-type tool, with the jaws being pivotally connected to each other. The two handles may each have an opening on the outward-facing side so that when the jaw-type tool is extended they can pivot around the two handle pivots where the jaws are attached to the handles, and when pivoted the handles can receive the jaws through the openings so the jaws can then be stored within the cavities. When the jaws are extended, lock mechanisms may be deployed in accordance with one aspect of the invention to prevent the handles from pivoting around the pivot axes of the handle pivots where the jaws are attached, thereby enabling the handles to open the jaws even in the event a force is exerted on the outside of the jaws that would otherwise cause the handles to collapse and pivot around the jaws as for storage.
In one such embodiment, the lock mechanism may be located at the jaw pivot point connecting the two jaws together. The lock mechanism may extend outward radially to close proximity with the handles, and can be engaged or retracted by pushing on a part of the lock mechanism itself.
In another embodiment of this aspect of the tool, a spring could be deployed from a sidewall of each handle upon extending the jaws, and could be released by one or more release buttons when the user is ready to retract the jaws back into the handles.
A multi-function tool including an embodiment of another aspect of the present invention provides for each respective handle utilizing multiple pieces in its construction, the pieces separately including walls of the channel running longitudinally so that the distance between the walls formed by the separate pieces is expandable and retractable to more precisely fit the total thickness of the combined tools and other separating spacers interspersed therebetween. The pivot axes for the tools carried in each handle are any of a variety of types of screw studs that can be appropriately tightened axially to control or eliminate unwanted lateral clearance or “play” and simultaneously secure the multiple parts of the handle.
As yet another aspect of a multi-function tool, a singular or multiple blade lock mechanism may be located on the distal end of each of the two handles of the tool, the end opposite where the jaws are connected to the handles. A substantial portion of the components of the blade lock mechanism are located further toward the distal end of the handle than the hinge or pivot point of a tool located at the distal end of the handle, with the release mechanism optionally being located at or between the two pivots but located on the outside of the handle walls, thereby reducing or eliminating the need for space for the release mechanism in the blade or tool cavity.
In one embodiment, such a blade lock mechanism has a torsion spring located distal to the pivot point or hinge, and may have its own pivot to secure the spring and lock mechanism. In another series of embodiments, a blade spring mechanism may be disposed around this spring pivot (even if the spring and/or lock mechanism are not used) to provide a force on the tang of each tool independently to help prevent so-called clumping when a tool is extended from its storage cavity within the handle.
As previously mentioned, these embodiments of various aspects and details of a multi-function hand tool may stand alone, or be used in any combination thereof, to provide a multi-function tool to meet associated needs. The resulting multi-function tool is then widely adaptable, strong, and user-friendly. The foregoing will become more readily understood upon consideration of the following detailed description, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of a multipurpose folding tool which is an embodiment of the present invention, in the folded or collapsed position.
FIG. 2 is an elevational view of the tool shown in FIG. 1 with a pair of jaw-like tools extended from one end of the handles and various other tools partially extended at the other end of each handle.
FIG. 3 is a side elevational view of the jaw-type tool and a portion of each of the handles with a locking mechanism engaged to prevent the handles from pivoting or collapsing around the jaw-type tool.
FIG. 4 is a view similar to that of FIG. 3 , of the jaw-type tool and a portion of each of the handles with the locking mechanism disengaged to allow the handles to collapse pivotally around the jaw-type tool.
FIG. 5 is a sectional view taken along line 5 - 5 of FIG. 3 , showing the locking mechanism engaged.
FIG. 5A is a sectional view taken along line 5 - 5 of FIG. 3 , showing the locking mechanism disengaged.
FIG. 5B is a side elevational view of the jaw-type tool and a portion of each of the handles, taken from the side opposite that shown in FIG. 3 .
FIG. 5C is a partially cutaway elevational view of the jaw-type tool and a portion of each of the handles with a sidewall locking mechanism engaged to prevent the handles from pivoting or collapsing around the jaw-type tool.
FIG. 5D is sectional view taken along line 5 D- 5 D of FIG. 5C , showing the locking mechanism engaged.
FIG. 5E is a side elevational view of the jaw-type tool and a portion of each of the handles with a sliding sidewall locking mechanism engaged to prevent the handles from pivoting or collapsing around the jaw-type tool.
FIG. 5F is a sectional view taken along line 5 F- 5 F of FIG. 5E , showing the interaction of the sliding sidewall locking mechanism with the side of the handle.
FIG. 6 is a partially cutaway elevational view of a portion of the multipurpose folding tool, including a blade lock mechanism including a torsion spring.
FIG. 7 is a partially cutaway view taken along line 7 - 7 of FIG. 6 showing the torsion spring more clearly.
FIG. 8 is an elevational view, similar to that of FIG. 6 , showing the blade lock in the disengaged position.
FIG. 9 is a side elevational view of a part of the tool including a blade lock release mechanism which is another embodiment of a blade lock according to the present invention.
FIG. 10 is a partially cutaway view taken in the direction of line 10 - 10 of FIG. 9 , showing a similar blade lock mechanism including a leaf spring.
FIG. 11 is a partially cutaway elevational view of the part of the tool shown in FIG. 9 , showing the blade lock in the engaged position.
FIG. 12 is a view similar to that of FIG. 11 , showing the blade lock in the disengaged position.
FIG. 13 is a side elevational view of a part of a multi-purpose tool including a latch mechanism that is another embodiment of one aspect of the present invention, including a rotational blade lock release mechanism located within the walls of the handle.
FIG. 13A is a side elevational view similar to that of FIG. 13 , showing the rotational blade lock release mechanism located outside the walls of the handle.
FIG. 14 is a partially cutaway view taken along line 14 - 14 of FIG. 13 , showing the blade lock mechanism.
FIG. 15 is a partially cutaway elevational view of the part of the tool shown in FIG. 13 , showing the blade lock in the engaged position.
FIG. 16 is a partially cutaway elevational view of the part of the tool shown in FIG. 13 , showing the blade lock in the disengaged position.
FIG. 17 is a side elevational view of a part of a multi-function tool including a blade lock that is another embodiment of one aspect of the present invention, including a sliding blade lock release mechanism.
FIG. 18 is a sectional view taken along line 18 - 18 of FIG. 17 , showing a spring and slider plate included in the blade lock release mechanism.
FIG. 19 is a sectional view of the part of a multi-function tool shown in FIG. 17 , taken on line 19 - 19 of FIG. 18 , and showing the blade lock in the engaged position.
FIG. 20 is a partially cutaway elevational view of the part of the tool shown in FIG. 17 , showing the blade lock in the disengaged position.
FIG. 21 is a side view of a shoulder stud and cap screw fastener system.
FIG. 22 is a side view of an alternate shoulder stud fastener system.
FIG. 23 is a side view of a peened shoulder stud fastening system.
FIG. 24 is a side view of a modified screw and stud fastening system
FIG. 25 is a side view of a screw stud fastening system.
FIG. 26 is a perspective view of a handle embodying another aspect of the present invention, showing a rivet connection.
FIG. 27 is a sectional view taken along line 26 showing two handle halves riveted together.
FIG. 28 is a perspective view of the handle depicted in FIG. 25 , rotated about its longitudinal axis to show a handle brace.
FIG. 29 is a perspective view of a handle embodying overlapping plates interconnected with two rivets.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIGS. 1 and 2 of the drawings, a folding multi-function tool 10 shown folded in FIG. 1 includes a jaw-type tool with jaws 70 being pivotally rotatable around a pivot assembly 72 . The jaws 70 may be pliers, scissors, pruners, wire cutters, crimpers, shears, etc, or may even contain combinations, as is known in the art. A jaw lock cylinder 74 is contained within the pivot assembly 72 , and will be more fully explained later in this disclosure. The jaws 70 are each connected to one of a pair of handles 20 by respective fasteners 30 . The handles 20 each have a jaw lock recess 22 for interaction with the jaw lock cylinder 74 . At the other end of the handles 20 , one or more tools 60 are secured to the handles 20 by fasteners 30 . The tools 60 may include screw drivers, can openers, files, saws, awls, flashlights, scissors, pens, cork screws, etc. in any desired combination. When fully extended, the tools 60 may be secured by a locking mechanism to be disclosed later. A blade lock release arm 40 is used to release the locking mechanism so that the tool 60 may be returned to a storage cavity 61 (seen best in FIG. 28 ) defined within the handle 20 . FIG. 2 provides a representative view of the various tools 60 at least partially extended from the stowed position, and FIG. 1 shows the multi-functional tool 10 with all representative tools in the stowed position.
Turning now to FIGS. 3 , 4 , 5 , and 5 A, the jaw locking mechanism will now be explained. In FIG. 3 , the jaws 70 are extended with respect to the handles 20 and rotated into a closed position about pivot assembly 72 , with respect to each other. A jaw lock cylinder 74 is contained within pivot assembly 72 , and can be stowed basically within the pivot assembly 72 as shown in FIG. 5A , or may be moved partially out of the pivot assembly 72 , as shown in FIG. 5 . Each jaw 70 has a jaw mount base portion 69 where it is mounted pivotally to the handle 20 by a fastener 30 . Since each jaw 70 is mounted to a handle 20 and the two jaws 70 are pivotably inter-connected at pivot assembly 72 , the jaws 70 can be opened and closed by relative movement of the handles 20 .
A nominal amount of friction between the handles 20 and the jaw mount base portions 69 keeps the handles from collapsing about the jaw mount base portions 69 during use. This nominal friction force must be overcome when moving the jaws 70 from their opened position as shown in FIGS. 3 and 4 to their stowed position within the handles 20 . An opening stop 71 of one jaw 70 interfaces with a mount stop 73 of the other jaw 70 to provide a positive stop for opening the jaws 70 , thereby providing a maximum jaw opening angle 76 as shown in FIG. 4 . When the jaw lock cylinder 74 is stowed within the pivot assembly 72 ( FIG. 5A ), efforts to move the handles 20 past the maximum jaw opening angle 76 will overcome the friction force, thereby allowing the handles to collapse as shown in FIG. 4 . Similarly, if a sufficient force acts on the outer sides 77 of the jaws 70 , and if the handles 20 are then separated, the friction force will be overcome and the jaws 70 will swing around fasteners 30 . Completion of this motion will allow the jaws 70 to pass through openings and be stored within the confines of the storage cavities 61 of the handles 20 as shown in FIG. 1 .
If, on the other hand, jaw lock cylinder 74 is moved to protrude partially out of the pivot assembly 72 ( FIG. 5 ), it engages itself with the jaw lock recess 22 of each handle 20 and thus prevents the jaws 70 from being collapsed about the fasteners 30 . The handles 20 are able to open and close the jaws 70 about the pivot assembly 72 , but in the event the friction force is overcome, the jaw lock recess 22 of each handle 20 will contact the jaw lock cylinder 74 , which will act as a mechanical stop, thereby preventing the jaws 70 from being collapsed. The jaw lock recess 22 may be shaped to closely match the shape of the jaw lock cylinder 74 as shown in the FIGS., but such a match is not necessary. The jaw lock recess 22 is shown in a cylindrical shape, but may take other shapes as desired, so long as it is capable of preventing the jaws 70 from being collapsed into the handles 20 .
As shown in FIGS. 5 , 5 A and 5 B, the jaw lock cylinder 74 is surrounded by and supports a lock cylinder flange 75 . The pivot assembly 72 includes a pair of inwardly extending rims that define a flange recess 76 that allows the jaw lock cylinder 74 to slide between the positions shown in FIGS. 5 and 5A , with the inwardly directed rims of the flange recess 76 interacting with the lock cylinder flange 75 to provide positive mechanical stops. A finger access opening 78 is provided where shown in FIGS. 5 , 5 A and 5 B and is exposed on the side of the tool opposite the end of the cylinder 74 shown in FIGS. 3 and 4 , so that the user can push the contained lock cylinder 74 partially out of the pivot assembly 72 , thereby allowing it to interact with handles 20 . The lock cylinder flange 75 may be an annular wire form extending approximately 340 degrees around the lock cylinder 74 and mating into a circumferential groove 75 A (see FIG. 5 ) in the lock cylinder 74 . By utilizing a wire form and heat treating as necessary, the wire form can act as a spring providing frictional resistance between the internal wall of the flange recess 76 and the exterior edge of the wire form. By making the wire form somewhat circumferentially shorter than a full circle, it could be compressed into the circumferential groove 75 A of the lock cylinder 74 , allowing for manufacture and assembly of the lock cylinder 74 into the pivot assembly 72 . Alternatively, the lock cylinder flange 75 may be a gasket, a spring, one or more dogs, or other means of providing positive stops. The pressure needed to move the jaw lock cylinder 74 can be as little or as much as desired, and may be controlled by the type of fit between the lock cylinder flange 75 and the flange recess 76 , or the jaw lock cylinder 74 or the pivot assembly 72 may contain other spring mechanisms (not shown) to provide resistance. The jaw lock cylinder 74 can be returned to its position within the pivot assembly 72 by pushing it back in. In the embodiment shown, an additional finger access opening is not required because the jaw lock cylinder 74 is easily accessible, but one may be added if desired.
In an alternate embodiment shown in FIGS. 5C and 5D , a sidewall of each handle 20 could contain a spring 79 that extends from the sidewall of the handles 20 toward the base portions 69 of the jaws 70 after the jaws 70 are fully extended from the storage cavity 61 . The spring 79 extending from the sidewall of the handle would interface with the opening stop 71 of the jaws 70 when the jaws 70 are fully opened. This spring 79 could replace the function of the mount stop 73 of the jaws 70 shown in FIG. 4 , in that the spring 79 then determines the maximum opening angle 76 of the jaws 70 , and also acts as a jaw lock, preventing the handles 20 from being folded with respect to the jaws 70 . The spring 79 can be pushed back into the handle 20 when the user is ready to collapse the jaws 70 for storage. This type of lock, known as a liner lock, has been heretofore limited to use in locking folding knife blades.
In another alternate embodiment shown in FIGS. 5E and 5F , a sidewall of each handle 20 could contain a sliding sidewall locking mechanism 150 . The sliding sidewall locking mechanism contains a sliding rod 154 located on the inner sidewall of handle 20 , and capable of being moved longitudinally along the handle wall via a thumb pad 156 mounted onto the sliding rod 154 via one or more mechanical attachments 160 . It is requisite that the sidewall of the handle 20 has a slot 162 cut into it for allowing the mechanical attachments 160 room to slide. Each of the base portions 69 of the jaws 70 contains a shaped recess 68 for receiving an end of the sliding rod 154 . By urging the end of the sliding rod 154 into the shaped recess 68 , the handles 20 are rigidly secured to the jaws 70 . When the sliding rod 154 is urged out of, and away from the shaped recess 68 , the jaw 70 is then free to rotate about the fastener 30 . A protrusion 152 may be placed on the sliding rod 154 to interact with a detent 156 placed on the handle as a means of preventing unwanted sliding of the rod 154 .
Turning now to FIGS. 2 and 6 - 8 , a blade lock release arm 40 extends through a lock release opening 50 in the wall of handle 20 . As shown in FIG. 7 , the blade lock release arm 40 is accessible from either side of the handle 20 , and is attached to locking body 42 of the blade lock. A blade lock pivot pin 46 runs through a lock sleeve 48 and a torsion spring 44 , thereby providing rotational force upon the locking body 42 of the blade lock. As shown in FIG. 2 , the blade lock pivot pin 46 is located distal to the fasteners 30 and to the blade lock release arm 40 . The torsion spring 44 urges the locking body 42 toward the tang of the blade or tool. One or more tools or blades 60 pivot about fastener 30 , from a retracted or closed position within the storage cavity 61 in the handle 20 to an extended and locked position. The base or tang portion of the blade 60 contains a blade storage recess 65 , a blade hinge recess 62 and a blade lock catch 64 . While the blade is in the stowed position within the cavity of the handle 20 , the locking body 42 is able to rest in the blade storage recess 65 without touching the blade vertical wall of the blade storage recess 65 , but while resting on the horizontal surface 67 on the tang end of the blade. The peripheral surface 66 of the tang end of the blade 60 is curved such that the blade 60 may be rotated out of the cavity in the handle 20 by overcoming the torsional force caused by the blade torsion spring 44 on the horizontal surface 67 , and the small amount of friction force between the horizontal surface 67 and the blade locking body 42 . When the blade 60 is fully rotated out of the handle 20 , the blade hinge recess 62 allows the blade 60 to extend substantially co-linear with the handle 20 , without interference from the blade lock pivot pin 46 , as shown in FIG. 8 , and the locking body 42 is able to engage the perpendicular face of the blade lock catch 64 . With the locking body 42 engaged, the blade 60 is held firmly, preventing it from rotating back into the cavity 61 in the handle 20 . The blade 60 is prevented from over rotating by the blade stop 86 of the handles 20 . To release the blade 60 from the extended position, the operator would rotate the blade lock release arm 40 and thereby move the locking body 42 around the blade lock pivot pin 46 , away from the tang end of the blade 60 as indicated by arrow 88 in FIG. 6 . A force arrow 87 allows the blade lock to be shown in the release position in FIG. 8 , such that the blade 60 could be rotated back to the stored position.
Another locking mechanism embodiment, as shown in FIGS. 9-12 , utilizes the locking body 42 , blade lock pivot pin 46 , and lock sleeve 48 . A leaf spring 45 provides the resistant force to urge the locking body 42 toward the blade 60 . One end of the leaf spring 45 is held securely at an anchor point 49 in handle 20 as best seen in FIG. 11 , and the spring 45 extends to contact the locking body 42 to urge it toward the tang of the blade 60 . A lock release lever 41 extends from the locking body 42 and runs parallel to the internal surface of the side wall of the handle 20 . A release tab 80 is conveniently exposed on the outer side of the side wall of the handle 20 and has a shaft that extends through a lock release opening 52 in the side wall and is attached to a release tab interface 82 such as a collar fitted on the shaft and located inside the cavity of the handle 20 , so that the lock release lever 41 extends over the release tab interface 82 . The tab release interface 82 is large enough in diameter that it cannot be extracted through the lock release opening 52 , and it may be attached to the release tab 80 by any known mechanical means. The release tab 80 and the release tab interface 82 must fit together with sufficient clearance along the shaft that the combination may be moved through the range provided by the lock release opening 52 . Release of the locking body 42 is accomplished by sliding the release tab 82 as indicated by the arrow 89 so that the locking body 42 rotates out of engagement with the blade lock catch 64 of the blade 60 , at which time the blade may be rotated back to its stowed position in the cavity 61 .
In yet another locking mechanism embodiment shown in FIGS. 13-16 , a rocker release tab 90 is located within the cavity 61 of, and runs parallel to the side wall of the handle 20 . Alternatively, as shown in FIG. 13A , the rocker release tab 90 can be located on the outside wall of the handle 20 , with the rocker lever 94 interfacing with the locking body 42 by either the rocker lever 94 extending inward through a wall cavity to contact the locking body 42 , or the locking body 42 extending through the wall cavity to contact the rocker lever 94 external to the cavity 61 . In either case, the rocker release tab 90 is pivotal about rocker hinge 92 mounted in the side wall, and carries a rocker lever 94 that extends to contact the locking body 42 . This embodiment as shown utilizes the torsion spring 44 to urge the locking body 42 toward the tang of blade 60 , and either into the blade storage recess 65 of the blade 60 when the blade 60 is in the stowed position, or into engagement with the blade lock catch 64 when the blade 60 is in the extended position. The blade lock again utilizes lock sleeve 48 to rotate around blade lock pivot pin 46 , which is again located distal to the fastener 30 at the distal end of the handle 20 . Movement of the release tab 90 in the direction of the arrow 95 raises the locking body 42 out of engagement with the blade lock catch 64 , overcoming the force of the torsion spring 44 to release the blade 60 .
FIGS. 17-20 show yet another embodiment of the blade lock arrangement, wherein a slide release tab 100 is utilized to move the locking body 42 . In this embodiment, a slide release tab 100 may be located on each side of the handle 20 , and the two tabs are joined by slide cross brace 102 . Slide cross brace 102 is in turn mechanically joined by a rivet 104 , a spot weld, or other known means to slide frame 106 . At the medial end of slide frame 106 , a serpentine spring 108 is attached to the base of the handle 20 by spring pins 109 . The distal end of slide frame 106 defines a hole in which a slide lever interface arm 47 is movably engaged. The slide lever interface arm 47 is in turn attached fixedly to the blade locking body 42 , with the slide lever interface arm 47 being roughly perpendicular to the locking body 42 . The blade locking body 42 and the lever interface arm 47 are carried on a lock pivot pin 110 mounted rotatably in the side walls of the handle 20 at a location distal of the fasteners 30 about which the blade 60 can rotate. As shown, the lever interface arm 47 , the locking body 42 , and the pin 110 are a unitary element, but it will be understood that the pin 110 could be separate, with a sleeve similar to the sleeve 48 carrying the locking body 42 and the interface arm 47 if ample space is provided. In this embodiment of the blade lock, when the slide release tabs 100 are moved toward the distal end of the handle 20 , the slide lever interface arm 47 rotates the lock pivot pin 110 , thereby moving the locking body 42 away from the tang of blade 60 so that the blade 60 may rotate about the fastener 30 to either a stowed or an extended position. The serpentine spring 108 is compressed as the slide release tabs 100 and slide cross brace 102 are moved toward the distal end of the handle 20 and then urges the slide cross brace 102 away from the distal end of the handle 20 when the slide release tabs 100 are released.
In the various locking mechanism embodiments presented, a torsion spring 44 , a leaf spring 45 , or a serpentine spring 108 has been shown and may be interchangeable within the various embodiments, the requirement solely being to urge the locking body 42 toward the tang of the blade 60 . Other springs, such as a helical compression spring, may be utilized to achieve the same result and fall within the scope of this invention.
FIGS. 26-29 detail embodiments of the handles 20 of the folding multi-function tool 10 . Each handle 20 contains two handle halves 19 and 21 . Each handle half 19 and 21 defines a jaw lock recess 22 at its proximal end, and fastener holes 24 for receiving fasteners 30 at each end. The two handle halves 19 and 21 each contain a sidewall, a top portion and a bottom portion. One handle half 21 contains a male handle brace 28 , and the other handle 19 contains a female handle brace 27 , and the two braces intertwine to provide stability to the bottom portion of the handle 20 , and to engage the base of the associated one of the jaws 70 to carry squeezing forces from the handle 20 to the jaw to urge the jaws to close toward each other to grip an object or in operation of scissors or shears. The male and female braces are kept together by appropriate tension in the fastener 30 at the proximal end of the handle. At the distal end of each handle 20 top portion of the handle half 21 overlaps a portion of handle half 19 , as shown in section view of FIG. 27 , and the overlapping portions are attached to each other by handle rivet 23 or other suitable mechanical means. Optionally, portions of each of handle halves 19 and 21 could overlap portions of the other handle half, with both overlapping sections being mechanically inter-connected by handle rivets 23 as shown in FIG. 29 . A jaw-receiving opening 32 is defined in the top of the proximal end of each handle 20 to permit the jaws 70 to be folded into the storage cavity 61 . By including structural support for the handles 20 on both the top and bottom portions, the handles 20 can be made to be more structurally sound and stable. The sidewalls of handle 20 may be straight-walled, or may be ergonomically designed as desired, and may have an appropriate coating or cover of a different material than that of the structural handle halves 19 and 21 .
Details of the fasteners 30 are shown specifically in FIGS. 21-25 . FIG. 21 shows an internally threaded peened stud 122 mating with side walls 120 and being attached by a raised countersunk head screw 132 at one end and a cap screw 134 at the other, which may be used as fastener 30 . Alternative heads, such as a countersunk head 136 shown in FIGS. 22 and 23 may be used to provide a surface generally flush with side walls 120 , with the respective studs 124 or 126 having flanges to interact with side walls 120 . The exterior wall of the various studs 122 , 124 , 126 , 128 , or 130 acts as the pivot joints for the various blades 60 or jaw mounts 69 . Utilization of the handle halves 19 and 21 , combined with threaded fasteners 30 in any combination of the forms presented in FIGS. 21-25 allow for precise coaxial adjustment of the handles 20 on the jaws mounts 69 and the various blades 60 .
FIG. 25 shows an alternative attachment method with an internally threaded button head stud 130 going through the side wall 120 and mating with a button head cap screw 140 . A sliding sleeve 121 travels through the side wall 120 and bears against the stack of blades 60 to allow infinite adjustability in the case where the handle 20 is one solid piece instead of the two mating pieces shown in FIGS. 26-29 . The infinite adjustability offered by tightening the button head cap screw 140 against the sliding sleeve 121 , and consequently against the stack of blades 60 provides a significant amount of dimensional tolerance, thereby reducing manufacturing costs.
While the invention has been described in some embodiments, it should be readily apparent to those skilled in the art that many modifications, additions, and deletions may be made therein without departing from the spirit and scope of the invention. Various embodiments of the invention may be utilized alone, or in any combination. The invention is therefore not intended to be limited by the explicitly disclosed embodiments provided, but rather by the appended claims. | A multi-function hand tool with a pivotally collapsible jaw-type tool that has a jaw lock which mechanically prevents the jaw-type tool from collapse is disclosed. The jaw lock mechanism is contained within the jaw pivot joint of the jaw-type tool, and may be partially extended as a push button to prevent unwanted handle collapse. A plurality of blades are pivotally attached to the opposite end of the multi-function tool and has a blade locking mechanism wherein the blade lock is pivoted about an axis located distal to the blade fastener/pivot axis. Each handle of the multi-function tool may be made of two individual handle halves that unite to form the handle, but that provide very precise tensioning, or the handles may be of a single channel shape using an infinitely adjustable threaded fastener and sleeve to provide precise adjustment of the multiple blades. | 1 |
RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent application Ser. No. 09/691,779, filed Oct. 18, 2000, now abandoned, which is a divisional of U.S. patent application Ser. No. 09/552,236, filed Apr. 19, 2000, now U.S. Pat. No. 6,323,310 both incorporated by reference herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is broadly concerned with anti-reflective compositions and methods of forming the compositions for use as anti-reflective coating (ARC) layers on substrates during integrated circuit manufacturing processes. More particularly, the inventive compositions are formed by polymerizing aminoplasts (e.g., melamine, benzoguanamine) in an acidic environment under elevated temperatures to yield cross-linkable, UV absorbing, fast etching compositions.
2. Description of the Prior Art
A frequent problem encountered by photoresists during the manufacturing of semiconductor devices is that activating radiation is reflected back into the photoresist by the substrate on which it is supported. Such reflectivity tends to cause blurred patterns which degrade the resolution of the photoresist. Degradation of the image in the processed photoresist is particularly problematic when the substrate is non-planar and/or highly reflective. One approach to address this problem is the use of a bottom anti-reflective coating (BARC) applied to the substrate beneath the photoresist layer.
Fill compositions which have high optical density at the typical exposure wavelengths have been used for some time to form these BARC layers. The BARC compositions typically consist of an organic polymer which provides coating properties and a dye for absorbing light. The dye is either blended into the composition or chemically bonded to the polymer. Thermosetting BARC's contain a cross-linking agent in addition to the polymer and dye. Cross-linking must be initiated, and this is typically accomplished by an acid catalyst present in the composition. As a result of all these ingredients which are required to perform specific and different functions, prior art BARC compositions are fairly complex.
U.S. Pat. No. 5,939,510 to Sato et al. discloses a BARC composition which comprises a UV absorber and a cross-linking agent. The UV absorber is a benzophenone compound or an aromatic azomethine compound having at least one unsubstituted or alkyl-substituted amino group on the aryl groups. The cross-linking agent disclosed by Sato et al. is a melamine compound having at least two methylol groups or alkoxymethyl groups bonded to the nitrogen atoms of the molecule.
The Sato et al. composition suffers from two major drawbacks. First, in the two-component composition disclosed, the Sato et al. composition does not include a polymeric material thus resulting in insufficient coverage on the surfaces and edges of the substrate features. Furthermore, the UV absorber disclosed by Sato et al. is physically mixed with the cross-linking agent rather than chemically bonded to some component of the composition. As a result, the UV absorber will often sublime, and in many cases sublime and diffuse into the subsequently applied photoresist layer.
There is a need for a less complex anti-reflective composition which provides high reflection control and increased etch rates while minimizing or avoiding intermixing with photoresist layers.
SUMMARY OF THE INVENTION
The present invention overcomes these problems by broadly providing improved anti-reflective compositions which are formed from a minimal number of components (e.g., two or less) and which exhibit the properties necessary in an effective BARC composition.
In more detail, anti-reflective compositions according to the invention include polymers comprising monomers derived from compounds of Formula I and mixtures thereof.
wherein each X is individually selected from the group consisting of NR 2 (with the nitrogen atom being bonded to the ring structure) and phenyl groups, where each R is individually selected from the group consisting of hydrogen, alkoxyalkyl groups, carboxyl groups, and hydroxymethyl groups. Preferred compounds of Formula I include the following:
When used in reference to Formula I, the phrase “monomers derived from compounds of Formula I” is intended to refer to functional moieties of Formula I. For example, each of the structures of Formula II is derived from compounds of Formula I.
wherein: each X is individually selected from the group consisting of NR 2 (with the nitrogen atom being bonded to the ring structure) and phenyl groups, where each R is individually selected from the group consisting of hydrogen, alkoxyalkyl groups, carboxyl groups, and hydroxymethyl groups; and “M 1 ” and “M 2 ” represent a molecule (e.g., a chromophore or another monomer derived from the compound of Formula I) bonded to X′ or X″. Thus, “monomers derived from the compounds of Formula I” would include those compounds where any of the constituents (i.e., any of the X groups, and preferably 1-2 of the X groups) is bonded to another molecule.
The polymerized monomers are preferably joined by linkage groups selected from the group consisting of-CH 2 —, —CH 2 —O—CH 2 , and mixtures thereof, with the linkage groups being bonded to nitrogen atoms on the respective monomers. For example, Formula III demonstrates two methoxymethylated melamine moieties joined via a —CH 2 — linkage group and two methoxymethylated melamine moieties joined via a —CH 2 —O—CH 2 — linkage group.
Formula IV illustrates two benzoguanamine moieties joined via CH 2 linkage groups.
Finally, Formula V illustrates two methoxymethylated melamine moieties having a chromophore (2,4-hexadienoic acid) bonded thereto and joined via CH 2 linkage groups.
The inventive compositions are formed by providing a dispersion of the compounds of Formula I in a dispersant (preferably an organic solvent such as ethyl lactate), and adding an acid (such as p-toluenesulfonic acid) to the dispersion either prior to or simultaneous to heating of the dispersion to a temperature of at least about 70° C., and preferably at least about 120° C. The quantity of acid added should be from about 0.001-1 moles per liter of dispersant, and preferably from about 0.01-0.5 moles of acid per liter of dispersant. Furthermore, the heating step should be carried out for at least about 2 hours, and preferably from about 4-6 hours. In applications where only benzoguanamine-based moieties are utilized, the heating step should be carried out for a time period of less than about 7 hours, and preferably from about 5.5-6.5 hours.
Heating the starting compounds under acidic conditions causes the compounds to polymerize by forming the previously described linkage groups. The polymers resulting from the heating step should have an average molecular weight of at least about 1,000 Daltons, preferably at least about 5,000 Daltons, and more preferably at least about 5,000-20,000 Daltons. Furthermore, about 12 hours after the heating step the resulting anti-reflective composition should have a decrease of at least about 20%, preferably at least about 40%, and more preferably from about 40-70% in methoxymethylol (—CH 2 OCH 3 ) groups than were present in the starting dispersions of Formula I compounds, with the quantity of methoxymethylol groups being determined by the titration procedure as herein defined.
It will be appreciated that the inventive polymer compositions provide significant advantages over prior art compositions in that the polymerized compositions alone act as conventional anti-reflective coating polymer binders, cross-linking agents, and chromophores, thus greatly simplifying the anti-reflective coating system.
In applications where enhanced light absorbance is desired, a chromophore (e.g., 2,4-hexadienoic acid, 3-hydroxy-2-naphthoic acid) can be mixed with the starting dispersion prior to acid and heat treatment. During subsequent acid treatment, the chromophore will chemically bond to the monomers during polymerization.
The resulting polymerized composition is mixed with a solvent to form an anti-reflective coating composition. Suitable solvents include propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, and cyclohexanone. The anti-reflective coating composition is subsequently applied to the surface of a substrate (e.g., silicon wafer) by conventional methods, such as by spin-coating, to form an anti-reflective coating layer on the substrate. The substrate and layer combination is baked at temperatures of at least about 160° C. The baked layer will generally have a thickness of anywhere from about 500 Å to about 2000 Å.
In an alternate embodiment, an anti-reflective composition is formed by preparing a dispersion including, in a dispersant (e.g., propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate), a quantity of the compound of Formula I and a polymer having cross-linking sites therein. The composition should comprise at least about 1.5% by weight of the polymer, and preferably from about 2.0-20% by weight of the polymer, based upon the total weight of the solids in the composition taken as 100% by weight. The molecular weight of the polymer is at least about 2,000 Daltons, and preferably from about 5,000-100,000 Daltons. The cross-linking sites on the polymer preferably comprise a cross-linking group selected from the group consisting of hydroxyl, carboxylic, and amide groups. The most preferred polymers include cellulose acetate hydrogen phthalate, cellulose acetate butyrate, hydroxypropyl cellulose, ethyl cellulose, polyesters, polyacrylic acid, and hydroxypropyl methacrylate.
In this embodiment, it is not necessary to heat the dispersion. However, as was the case with the first embodiment, the composition preferably includes an acid such as p-toluenesulfonic acid. Advantageously, it is not necessary to add a chromophore to the composition as the compound of Formula I also functions as a light-absorber. Thus, the composition is preferably essentially free (i.e., less than about 0.5% by weight, preferably less than about 0.1% by weight, and more preferably about 0% by weight) of any added chromophores.
In either embodiment, it is preferred that the polymers comprising monomers derived from compounds of Formula I and/or the mixture of Formula I compounds be present in the composition at high levels. These levels are preferably from about 60-98% by weight on a solids basis, and more preferably from about 75-96% by weight on a solids basis.
In either embodiment, low molecular weight (e.g., less than about 13,000 Daltons) polymeric binders can be utilized in the dispersion (after heating and acidification steps in the case of the first embodiment) to assist in forming highly planar layers. Alternately, a high molecular weight polymeric binder (e.g., acrylics, polyester, or cellulosic polymer such as cellulose acetate hydrogen phthalate, hydroxypropyl cellulose, and ethyl cellulose) having a molecular weight of at least about 100,000 Daltons can be mixed with the starting dispersion (also after heating and acidification steps in the case of the first embodiment) to assist in forming conformal layers. This will result in an anti-reflective layer having a percent conformality of at least about 60%, even on topographic surfaces (i.e., surfaces having raised features of 1000 Å or greater and/or having contact or via holes formed therein having hole depths of from about 1000-15,000 Å).
As used herein, percent conformality is defined as: 100 · ( thickness of the film at location A ) - ( thickness of the film at location B ) ( thickness of the film at location A ) ,
wherein: “A” is the centerpoint of the top surface of a target feature when the target feature is a raised feature, or the centerpoint of the bottom surface of the target feature when the target feature is a contact or via hole; and “B” is the halfway point between the edge of the target feature and the edge of the feature nearest the target feature. “Feature” and “target feature” is intended to refer to raised features as well as contact or via holes. As also used in this definition, the “edge” of the target feature is intended to refer to the base of the sidewall forming the target feature when the target feature is a raised feature, or the upper edge of a contact or via hole when the target feature is a recessed feature. Percent planarization is defined as:
100-% conformality.
Regardless of the embodiment, anti-reflective layers formed according to the invention will absorb at least about 90%, and preferably at least about 95%, of light at wavelengths of from about 190-260 nm. Furthermore, the anti-reflective layers have a k value (i.e., the imaginary component of the complex index of refraction) of at least about 0.2, and preferably at least about 0.5, at the wavelength of interest. Finally, the anti-reflective layers have high etch rates, particularly when melamine is utilized. The etch selectivity to resist will be at least about 1.5, and preferably at least about 2.0 when CF 4 is used as the etchant.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph depicting the molecular weight distribution of polymerized Cymel® 303 as a function of reaction time;
FIG. 2 is a graph depicting the molecular weight distribution of polymerized Cymel® 303 having 3-hydroxy-2-naphthoic acid bonded thereto as a function of reaction time; and
FIG. 3 is a graph depicting the change in the methylol and methoxymethylol groups over time.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
EXAMPLES
The following examples set forth preferred methods in accordance with the invention. It is to be understood, however, that these examples are provided by way of illustration and nothing therein should be taken as a limitation upon the overall scope of the invention.
Testing Procedures
1. Stripping Test Procedure
In the following examples, a stripping test was performed to determine the resistance of the experimental anti-reflective coating (ARC) to photoresist solvents. In this procedure, an ARC formulation was spin-coated onto a silicon wafer at a spin speed of 2,500 rpm for 60 seconds and at an acceleration of 20,000 rpm/second. The film was baked on a hotplate at 205° C. for 60 seconds. The ARC film thickness was then measured at multiple points on the wafer using ellipsometry.
Ethyl lactate was puddled onto the silicon wafer for 10 seconds, followed by spin drying at 3,500 rpm for 30 seconds to remove the solvent. The film was then baked on a hotplate at 100° C. for 30 seconds. The ARC film thickness was again measured at multiple points on the wafer using ellipsometry. The amount of stripping was determined to be the difference between the initial and final average film thicknesses, with the uncertainty in the stripping measurement being the sum of the two average thickness measurement uncertainties.
2. Interlayer Formation Procedure
In the following examples, the degree of intermixing between the sample ARC and the photoresist was determined. In this procedure, an ARC formulation was spin-coated onto a silicon wafer at a spin speed of 2,500 rpm for 60 seconds and at an acceleration of 20,000 rpm/second. The film was baked on a hotplate at 205° C. for 60 seconds. The ARC film thickness was then measured at multiple points on the wafer using ellipsometry.
A photoresist (UV6, available from Shipley) was spin-coated on top of the ARC film at a spin speed of 3250 rpm for 30 seconds and at an acceleration of 20,000 rpm/second under ambient conditions. The wafer was then baked on a hotplate for 130° C. for 60 seconds and exposed to 20 mJ of exposure energy, after which a post-exposure bake was performed on the wafer at 130° C. for 90 seconds.
The photoresist was developed with Shipley LDD26W developer for 40 seconds. The sample was then rinsed with distilled water and spun dry at 2,000 rpm for 20 seconds followed by baking on a hotplate for 100° C. for 30 seconds. The film thickness was again measured at multiple points on the wafer using ellipsometry. The difference in the two film thickness averages (Å) was recorded as the interlayer stripping result with the uncertainty in the interlayer measurement being the sum of the two average thickness measurement uncertainties.
3. Titration Procedure
a. Free Formaldehyde Analysis
A 10% Na 2 SO 3 (aq) solution was prepared by mixing 50 g of Na 2 SO 3 with 450 g of water. A few drops of rosolic acid was added to this solution until it turned red after which 1N HCl (aq) was added to the solution until it turned to a color between pale pink and colorless. The shelf life of the resulting solution is 2-3 days.
The sample to be tested was prepared by mixing 1.5 g of the sample with 10 ml of 1,4-dioxane. Next, 20 g of the previously prepared 10% Na 2 SO 3 solution was added to the flask and the flask was agitated with a magnetic stirrer. While stirring, 1N HCl (aq) was titrated into the flask until the solution turned pale pink or colorless. The free formaldehyde was then determined by the following equation:
Y =[( A−BL )*(30.03/1000)*100 ]/W,
where “A” is the amount (in ml) of titrated 1N HCl, “BL” is the amount (in ml) titrated for a blank (i.e., 1,4-dioxane only), “W” is the weight of the sample in grams, and “Y” is the weight percent of free formaldehyde in the solution. Thus, the total free formaldehyde weight (X) is:
[(total solution weight in g)*(Y)]100.
b. —CH 2 OH Analysis
In this procedure, 1 g of the sample was mixed with 20 ml of 1,4-dioxane in a beaker followed by sonication for two minutes. The solution was then transferred to a flask, and the beaker was rinsed three times with 10 ml portions of water (for a total of 30 ml), with the rinse water being added to the flask after each rinsing. Next, 25 ml of I 2 (0.1N) and 10 ml of 2N NaOH (aq) were added to the solution, the flask was capped tightly, and the solution was allowed to stand for 10 minutes. The solution was then titrated with 0.1N Na 2 S 2 O 3 (aq) until it turned a purple-brown color. The percent —CH 2 OH was then determined according to the following equation:
% —CH 2 OH=( B−A )*0.1*(1.502/weight of sample in g )− X,
where “A” is the amount (in ml) titrated for a blank (i.e., 1,4-dioxane only), “B” is the amount (in ml) of titrated 0.1N Na 2 S 2 O 3 , and “X” is the total free formaldehyde weight determined as described in part (a) above.
c. —CH 2 OCH 3 Analysis
In this procedure, 1 g of the sample was mixed with 20 ml of 1,4-dioxane in a beaker followed by sonication for two minutes. The solution was then transferred to a flask, and the beaker was rinsed three times with 10 ml portions of water (for a total of 30 ml), with the rinse water being added to the flask after each rinsing. Next, 20 ml of 2N of H 2 SO 4 (aq) was added to the flask and the solution was allowed to stand for 20 minutes at a temperature of 30-35° C. To the solution, 25 ml of I 2 (0.1N) and 25 ml of 2N NaOH (aq) were added, the flask was capped tightly, and the solution was allowed to stand for 15 minutes at room temperature. An additional 20 ml of 2N H 2 SO 4 (aq) was mixed with the solution, and the solution was titrated with 0.1N Na 2 S 2 O 3 (aq) until it turned from a purple-brown color to colorless. The percent —CH 2 OCH 3 was then determined according to the following equation:
% —CH 2 OCH 3 =( B−A )*0.1*(1.502/weight of sample in g )− X,
where “A” is the amount (in ml) titrated for a blank (i.e., 1,4-dioxane only), “B” is the amount (in ml) of titrated 0.1 N Na 2 S 2 O 3 , and “X” is the total free formaldehyde weight determined as described in part (a) above.
EXAMPLE 1
Cymel® 303 (40.0 g, available from Cytec Industries, Inc., New Jersey) was dissolved in 180.0 g of ethyl lactate in a 500 ml round-bottomed flask. In a 50 ml beaker, 1.0 g of p-toluenesulfonic acid (pTSA) was dissolved in 20 g of ethyl lactate. The round-bottomed flask was fitted with a nitrogen source, a water condenser, and a thermometer, and the contents of the flask heated to 120° C. in an oil bath. The pTSA solution was added to the beaker via an addition funnel. The resulting solution was maintained at a temperature of 120° F. for 12 hours. During this 12-hour time period, 50 g aliquots of the solution were collected at 0 hours, 4 hours, 6 hours, 8 hours, and 12 hours, and labeled as Samples 1-5, respectively.
Each of the samples was cooled and filtered through a 0.1 micron filter. An anti-reflective coating was formulated from the cooled samples 1-5 by adding 73.0 g of propylene glycol monomethyl ether (PGME) to the cooled and filtered samples. The molecular weight distribution profiles of these samples were determined using a gel permeation chromatograph with a refractive index detector and 50 Å, 100 Å, and 500 Å Phenogel (Phenomenex) columns in series. These results are shown in FIG. 1 .
Silicon wafers were spin-coated with each of the above formulations at 2500 rpm for 60 seconds followed by drying and baking at 205° C. for 60 seconds. The film thickness was measured, and the optical parameters of the film were determined. This data is reported in Table 1. The etch selectivity to resist (DUV42) with CF 4 as the etchant was 1.52.
TABLE 1
Reaction
Stripping
Interlayer
time
Thickness
Test
Test
Sample
(hours)
Å
n
k
Å
Å
1
0
1341
2.08
0.182
−2 ± 11
30 ± 34
2
4
1657
2.07
0.247
−88 ± 41
84 ± 42
3
6
1728
2.08
0.229
−20 ± 17
93 ± 15
4
8
1741
2.07
0.237
−23 ± 21
92 ± 21
5
12
1877
2.07
0.237
−14 ± 13
101 ± 38
EXAMPLE 2
Cymel® 303 (40.0 g) and 8.0 g of 3-hydroxy 2-naphthoic acid were dissolved in 180.0 g of ethyl lactate in a 500 ml round-bottomed flask. In a 50 ml beaker, 1.0 g of pTSA was dissolved in 20 g of ethyl lactate. The round-bottomed flask was fitted with a nitrogen source, a water condenser, and a thermometer, and the contents of the flask heated to 120° C. in an oil bath. The pTSA solution was added to the beaker via an addition funnel. The resulting solution was maintained at a temperature of 120° F. for 12 hours. During this 12-hour time period, 50 g aliquots of the solution were collected at 0 hours, 4 hours, 6 hours, 8 hours, and 12 hours, and labeled as Samples 1-5, respectively.
Each of the samples was cooled and filtered through a 0.1 micron filter. An anti-reflective coating was formulated from samples 1-5 by adding 73.0 g of PGME to the cooled and filtered samples. The molecular weight distribution profiles of these samples were determined using a gel permeation chromatograph with a refractive index detector and 50 Å, 100 Å, and 500 Å Phenogel columns in series. These results are shown in FIG. 2 .
Silicon wafers were spin-coated with each of the above formulations at 2500 rpm for 60 seconds followed by drying and baking at 205° C. for 60 seconds. The film thickness was measured, and the optical parameters of the film were determined. This data is reported in Table 2. The etch selectivity to resist (DUV42) with CF 4 as the etchant was 1.40.
TABLE 2
Reaction
Stripping
Interlayer
time
Thickness
Test
Test
Sample
(hours)
Å
n
k
Å
Å
1
0
2255
2.08
0.477
−4 ± 17
40 ± 64
2
4
2021
2.07
0.459
2 ± 17
61 ± 27
3
6
1928
2.08
0.469
−2 ± 8
61 ± 34
4
8
1926
2.08
0.468
−7.8 ± 13
63 ± 11
5
12
1957
2.07
0.461
8.8 ± 0
50 ± 49
EXAMPLE 3
Cymel® 303 and Cymel® 1123 (see Table 3 for amounts) were dissolved along with 0.75 g of pTSA were dissolved in 150.0 g of ethyl lactate in a 500 ml round-bottomed flask. The flask was fitted with a nitrogen source, a water condenser, and a thermometer after which the flask contents were heated to 120° C. in an oil bath and maintained at this temperature for 12 hours. The sample was filtered through a 0.1 micron filter. An anti-reflective coating was formulated by adding PGME, p-toluenesulfonate or pyridine, and pyridinium tosylate (pPTS) to the prepared sample in the amounts indicated in Table 3.
The formulations were spin-coated on silicon wafers at 2500 rpm for 60 seconds followed by drying and baking at 205° C. for 60 seconds. The respective thicknesses of the films were measured, and the optical parameters were determined. This data is reported in Table 4.
TABLE 3
Cymel ®
Cymel ®
Total
Total
Formulation
303
1123
PGME
Ethyl lactate
pyridine
pPTS
pTSA
I
10 g
20 g
336.2 g
247.6 g
—
—
2 g
II
25 g
5 g
336.3 g
247.6 g
—
—
2 g
III
10 g
20 g
336.2 g
247.6 g
0.3 g
1.65 g
0.75 g
IV
25 g
5 g
336.2 g
247.6 g
0.3 g
1.65 g
0.75 g
TABLE 4
Formu-
Thickness
Stripping
Interlayer
Etch
lation
Å
n
k
Test Å
Test Å
Selectivity A
I
749
1.970
0.484
−2
39
1.3
II
720
2.106
0.363
0
30
1.6
III
747
1.945
0.461
2
40
1.3
IV
740
2.096
0.358
0
20
1.6
A Selectivity to resist (DUV42) with CF 4 as the etchant.
EXAMPLE 4
Cellulose acetate hydrogen phthalate (3.0 g and having an average molecular weight of about 100,000 Daltons) was dissolved in 130.5 g of PGME. Next, 11.5 g of Cymel® 1125,5.0 g of Cymel® 303,150 g of propylene glycol monomethyl ether acetate (PGMEA), and 1.15 g of pTSA was added to the prepared solution and allowed to dissolve completely. The resulting solution was then filtered through a 0.1 micron.
The prepared formulation was spin-coated on silicon wafers at 2500 rpm for 60 seconds followed by drying and baking at 205° C. for 60 seconds. The film thickness was measured, and the optical properties determined. This data is reported in Table 5. The percent conformality of the film was determined to be 60%.
TABLE 5
Thickness Å
n
k
Stripping Test Å
Interlayer Test Å
1280
1.92
0.35
0 ± 10
0 ± 40
EXAMPLE 5
Cymel® 303 (25 g) and Cymel® 1123 (5 g) were dissolved along with 2 g of pTSA in 247.6 g of ethyl lactate. The resulting mixture was heated to 120° C., and the methylol and methoxymethylol groups were measured over time according to above-defined titration procedure. These results are shown in FIG. 3 . As indicated by these results, the methoxymethylol groups decreased over time as the Cymel® polymerized. It is believed that the methylol groups maybe regenerating or that new methylol groups are forming during polymerization since the methoxymethylol groups are involved in the polymerization. | Improved anti-reflective coating compositions for use in integrated circuit manufacturing processes and methods of forming these compositions are provided. Broadly, the compositions are formed by heating a solution comprising a compound including specific compounds (e.g., alkoxy alkyl melamines, alkoxy alkyl benzoguanamines) under acidic conditions so as to polymerize the compounds and form polymers having an average molecular weight of at least about 1,000 Daltons. The monomers of the resulting polymers are joined to one another via linkage groups (e.g., —CH 2 —, —CH 2 —O—CH 2 —) which are bonded to nitrogen atoms on the respective monomers. The polymerized compound is mixed with a solvent and applied to a substrate surface after which it is baked to form an anti-reflective layer. The resulting layer has high k values and can be formulated for both conformal and planar applications. | 7 |
PRIORITY CLAIM
[0001] This application is a continuation of and claims priority to U.S. patent application Ser. No. 10/605,267 filed Sep. 18, 2003, which is a divisional of and claims priority to U.S. patent application Ser. No. 09/516,827 filed Mar. 1, 2000, and claims the benefit of U.S. provisional application Ser. No. 60/123,401 filed Mar. 8, 1999; each application is incorporated by reference in its entirety as if fully set forth herein.
FIELD OF THE INVENTION
[0002] This invention relates generally to systems and devices for removing unwanted and harmful moisture from wet and/or water damaged structures.
BACKGROUND OF THE INVENTION
[0003] Unwanted water, introduced by flooding, precipitation or otherwise, causes millions, if not billions, of dollars of damage to structures every year. Generally, the amount of damage can be reduced, minimized, or even eliminated if the water can be removed from the structure shortly after its undesired entry into the structure. For example, if the water can be extracted promptly in some manner from the structure generally, and then from the cavities within walls, floors and other structural elements, then rot, mold, rust and other destructive effects of the unwanted water can be minimized or avoided altogether.
[0004] Some early attempts to solve this problem involved simply passive drying, such as draining the visible water, and opening windows to let the hidden moisture evaporate. While this had the advantage of being relatively non-intrusive and non-destructive, it also generally took so long that it did not avert rot, mold, rust and the other destructive effects of the lingering moisture. Also, it left the structure relatively unusable for an undesirably long period of time.
[0005] Partly in response to those disadvantages, more active approaches were used, such as forcing air, heated or otherwise, through the afflicted structure so as to expedite the evaporation process. While this resulted in some improvement in many cases, generally, the results were still not satisfactory.
[0006] Other early attempts involved removal of some or all of certain structural elements to facilitate evaporation from enclosed areas. For example, in some cases floorboards or wallboards were removed to enable the moisture trapped in the wall or floor cavities to evaporate more effectively and sooner. The obvious disadvantage of such approaches is that they were so destructive as to require significant repair and/or replacement of the structure after the drying process, resulting in greater cost and often the loss of use of the structure for a longer period of time than would be the case without the destruction.
[0007] To overcome some of the disadvantages of the prior systems, some improved systems were developed. For example, in my prior patent application (application Ser. No. 08/890,141, filed Jul. 9, 1997 now pending,) I developed certain features of a system that dried structures more effectively and less destructively than previous systems. In that system, a blower forced air, either positively or negatively, to dry the afflicted structure. Specifically, in positive pressure mode, the blower would blow dry air through a hose, and into one or more manifolds, and then from the manifolds into a network of smaller tubes, and then into an injector that penetrated through a small hole in the structure. Conversely, when in negative pressure mode, the system would suck the damp air from the structure, out through the hole via the injector, and then through the tubes, the manifold, the hose, and ultimately out back through the blower.
[0008] While this system was a significant advance over prior systems, significant problems remained. Some shortcomings of my prior system, and other prior systems, included:
[0009] (1) Excessively destructive intrusion. Specifically, the prior system required that a plurality of relatively large sized holes be created in the structure. For example, in a high density material such as wood, a hole of {fraction (7/16)}″ diameter would be required. Holes this large require more effort in repair than would be required with smaller holes. While some prior systems have attempted to utilize smaller holes, the required air injectors were so small that they lacked convenient and effective means for preventing accidental withdrawal without damage to the structure. For example, when an injector was inserted into a wet sheetrock ceiling, the injector would have a tendency to fall out, especially in positive pressure mode. To date, previous attempts to prevent this problem have either not been effective, or have had undesirable side-effects, such as larger holes to accommodate fletching for friction to prevent withdrawal, angled penetration tending to cause damage upon removal, and threads for screwing in the injectors tending to cause a suboptimal amount of labor in the field.
[0010] (2) Clogging. In my prior system, the injectors included a small hole near the distal end of the injector tube. The purpose of this extra hole was in part to create extra airflow. However, the hole in the distal end was too close to the end of the injectory and thereby resulted in frequent clogging with wet drywall or other debris or matter within the wall or floor cavity. Because of the small surface area available, it could not be large enough as a single set of holes.
[0011] (3) Inefficiency and Expense in Mobilization and Demobilization. Perhaps the biggest problem with prior systems was the relatively large amount of labor required to assemble, reconfigure and disassemble them in the field. Since labor costs for restoration services are relatively high, even modest improvements in field efficiency can be extremely valuable.
[0012] (4) Interference with Facilities & Operations. Another disadvantage of my prior system, and all other drying systems of which I am aware, is the significant intrusion and interference with the structure being dried. That is, as a practical matter, while prior systems are being used to dry a structure, it is nearly impossible for the usual occupants of the premises being dried to conduct business therein. For example, in an office building, the office tenants must generally not return until the job is completed due to the extensive tangle of blowers, hoses and tubes radiating in all directions throughout the afflicted structure. In most prior systems also, the blowers are too loud to enable work in the structure until the job is completed.
[0013] (5) Inefficient air flow. Prior systems moved air inefficiently. Specifically, for example, in my prior system while in positive mode, dry air would be forced several feet down a trunk hose, and then into a manifold. From the manifold, some of the air would be dispersed into a tube which retraced back over the same distance to a hole in the structure close to the blower. This inefficiency was an inherent feature of the general configuration of our prior system, in that a main trunk line hose would transmit the air to a manifold, typically in the center of a room or wet area, and the manifold would then disperse the air through tubes all about the room. Thus, all other things being equal, higher pressure would be required to overcome the friction inherent in the system. Or, conversely, given a maximum amount of pressure sustainable by the blower in the system, the friction in the inefficient distribution of the prior systems would leave that much less effective air movement for actual drying at the point of the wet surface.
[0014] (6) Waste of Material. For much the same reason, the prior systems waste a considerable amount of material. Specifically, much more hosing and tubing is required than is with the present invention. This not only creates more manufacturing cost and labor in the field, but also tends to clutter the afflicted structure to the point of presenting a hazardous condition for occupants, such as by increased risk of tripping.
Special Difficulties with Hardwood Floors
[0015] Each of the foregoing difficulties with prior systems applied to drying any part of any structure in general, whether walls, ceilings, cabinets, or floors, or any cavities therein. However, particular difficulties are presented with hardwood floors. Hardwood floors, when damaged by excess moisture, can be very difficult to dry. Most homeowners, for example, are completely discouraged to see their floors commence to swell and cup, especially since such damage can occur after the floors only had water on them for as few as 20 minutes. In such cases, with current systems, the owner's alternatives are not good.
[0016] One option is total replacement if the area damaged is a large percentage of the entire hardwood area, and the cupping heavy, the option of complete replacement may currently be most appropriate. The full replacement is usually easy for the contractor to bid, with wet material removal and replacement fairly straightforward. However, unless the contractor is careful and accustomed to repairing water damaged structures, hardwoods are sometimes re-installed over damp subfloors. Extreme care must be taken to equalize the structure and the new hardwood prior to installation. In addition, total replacement is generally very costly. Another disadvantage is the total time the average home or office is unusable or substantially unusable. The average drying time even with equipment is 1-2 weeks just to dry the subfloor. This delay dramatically increases the total cost of the loss by reason of additional living expenses or loss of use.
[0017] A second option is partial replacement. Again however, the substrate must be dried to equilibrium, and the total repair time is close to that of complete replacement. A further disadvantage is that sometimes the wood cannot be matched to the owner's satisfaction.
[0018] Many restoration contractors attempt to dry hardwoods by one or a combination of the following: blowing air across the surface, dehumidifying (or tenting & pumping in dehumidified air), or blowing dry air from the wall area. The first option of blowing air across the surface does almost no good. The finishes and sealers prevent the moisture from being released easily. Dehumidifying accompanied by tenting seems good on the face but seldom works adequately and often causes the wood to check and crack.
[0019] Thus, it is an object of the present invention to also provide an improved and yet simple and inexpensive drying system particularly effective at drying hardwood and other similar floors.
SUMMARY OF THE INVENTION
[0020] The present invention provides an improved system for removing excess moisture from a structure. In accordance with the invention, several of the problems with prior systems are solved, and additional improvements are added. In addition, the present invention provides an improved system for removing excess moisture from hardwood and similar floors.
[0021] In accordance with the invention, several improvements are made to prior air distribution and collection systems. As with prior systems, a blower is provided to force air through a main trunk line hose. The main hose may terminate, or may return to the blower in a complete circuit. Also, as with prior systems, the invention may be operated in either positive or negative pressure mode (that is, it may either blow dry air into the structure, or suck wet air out of the structure through the air distribution network).
[0022] The manner of distribution of the air however, is completely new and improved in several respects. First, much smaller penetration holes can be used with the improved injectors. The new injectors are smaller than in previous systems, and yet have means for preventing accidental withdrawal. Specifically, each injector has locking tabs which can be depressed by the fingers of the user to reduce the effective diameter of the injector to facilitate insertion of the injector into the small hole. Once the injector is inserted however, the tabs can be released, and they will spring back into place, creating an effective diameter that is wider than the hole into which the injector was inserted, thereby preventing accidental withdrawal of the injector. This feature is particularly helpful in positive pressure mode, when the mere force of the air emanating from the injector will tend to dislodge the injector from the hole. It is also particularly helpful when drying ceilings, where the force of gravity tends to pull the injector out of the hole. This locking tab mechanism can also be easily removed without any damage to even fragile structures simply by re-pressing the tabs, and pulling.
[0023] The locking tab mechanism is a significant improvement over the prior systems, some of which relied either on fletchings or threads and friction (which required a larger injector diameter and hence a larger penetration hole and tended to result in damage around the edge of the hole in any case), and others of which lacked the friction fletchings and the larger hole, and were of small diameter, but which were not effective in preventing accidental withdrawal. Also, the locking tab mechanism makes it extremely easy to quickly and install and remove the injectors with zero damage to the structure other than the very small hole. The locking tab mechanism is not only much easier to use than the threaded or fletched injectors, but causes less damage. In the preferred embodiment a pair of opposing locking tabs are utilized, but either one or any number of tabs may be used in accordance with the invention.
[0024] Another aspect of the invention is the improved means for preventing clogging of the injector. My prior system provided an injector with a hole at the distal end, and another hole near the distal end to create Bernoulli effect. While this arrangement had advantages over prior systems, it also had practical disadvantages. Specifically, it had a tendency to clog, especially when drying sheetrock enclosed cavitities, or other structural cavities with debris therein. It accordance with the invention, the small hole near the distal end is replaced with one or more elongated slots resulting in greater alternate air source. Thus, if the hole at the end of the injector becomes plugged or clogged, the air may still be drawn in through the slot. Similarly, the slots are themselves less likely to become plugged than the small hole of prior systems. In prior systems, the hole was designed primarily for creating Bernoulli effect, and not for air removal as such, and for that reason was quite small. In the present invention, the slots serve a different purpose, and result in a more effective injector in practice, especially in negative pressure mode. In addition, even the small gaps surrounding the locking tab mechanism also serve to enable further air movement if the slots or end-hole become plugged or clogged.
[0025] The new injectors also provide a double barb near the proximal end. This double barb arrangement enables the injector to be used as a connector instead of an injector when desired. For example, in many uses, 2 individual air outlets need to be joined together to stop air escaping if not needed in the drying process. Instead of taking both injectors out and substituting a ⅜×⅜ connector, one injector can be removed and the second injector left in place and used as a connector of the unused lines. If operator desires to extend the length of the tubing, the injector may be left in place and another tube with injector attached, thereby lengthening the tube to get air where needed. Thus, the system is more versatile and convenient in use, because the injectors are configured to serve two functions, and a separate part (i.e., a connector) is not required.
[0026] A third fundamental aspect of the invention is the means for improved efficiency in mobilization and demobilization. Specifically, the configuration of the new system is considerably less cluttered, takes less time to assemble, deploy, reconfigure and disassemble.
[0027] Prior systems involved a trunk line hose feeding a manifold, which in turn distributed the air through a plurality of long tubes (see FIG. 1 ). The system of the invention instead distributes the tubes along the trunk line hose (see FIG. 2 ). As a result, considerably less tubing is required, and no manifold is required at all, resulting in lower manufacturing costs and a less expensive overall system for the user.
[0028] In addition, in a preferred embodiment of the new system, the tubes are preassembled, that is already attached in the trunk hose. Thus, the user need not even affix any of the tubes to a manifold. This feature, plus the generally less cluttered configuration as shown in FIG. 2 relative to FIG. 1 , results in a much easier system to use in the field.
[0029] In addition, the new configuration results in less interference with the afflicted structure. The shorter tubes being affixed along the trunk enable the system to be deployed in most applications around the perimeter of the afflicted room, leaving most of the room available for use.
[0030] The new configuration also distributes the air more efficiently in the sense of requiring less energy (typically electrical) and less tubing material per unit of air moved. By delivering air at the point of need, there is an elimination of tubing, eliminating need for air to travel through 3-4 unnecessary feet of tubing for each injector, faster setup, less trip hazard, less labor to carry in and setup. Thus, in summary, presently the drying art practiced has manifolds which are placed at infrequent intervals disposed along a trunkline. The disadvantages are in the area of messiness, excessive amounts of tubing required, trip hazard, increased friction due to extra lengths of tubing required and high labor costs to setup. The present invention solves each of these problems.
[0031] The new configuration could not be effected simply by multiplying the number of manifolds of the prior systems, in part because the labor and material costs would be prohibitive. Instead, a fundamentally new approach was required. Specifically, the distribution of the air more efficiently to the afflicted areas, without doubling back, required a fundamentally different configuration. The configuration of the present invention provided that fundamental difference. Specifically, it involved tubing along the main trunk hose. However, this configuration had to be accomplished in a manner that would retain the integrity of the main trunk hose, and was inexpensive and easy to use.
[0032] In accordance with the invention, the new system provides an active hoseline, by providing self-piercing scooped hose inserts. The scooped hose inserts penetrate the main hoseline at regular intervals (typically every 8 inches, for reasons explained below). The inserts are self-piercing, such that they can be inserted into the main hose simply by pushing them in by hand. This provides maximum versatility to the user in the field. The inserts further provide an air scoop, configured and oriented so as to catch the air passing through the hoseline in positive pressure mode, and efficiently inserting the air into the hoseline in negative pressure mode. The inserts further provide a barbed nozzle end for easily affixing the tubes.
[0033] Thus, in general, the self-piercing, self-sealing scooped hose inserts accomplish the function of distributing appropriate amounts of air from and to the main hoseline to the wet structure more directly, less expensively, and more efficiently than the manifold configuration of the prior systems. Less labor, less material, and less energy are required. In fact, the need for manifolds is completely eliminated. (Although a manifold can still be utilized when desired).
[0034] The insert is further unique in that it is capable of piercing a hose and self sealing with flanges on each side of the hose wall. On the proximal end there is a barbed opening for coupling a tube to it and the outer flange is curved to accommodate the outside surface of the hose. This results in the flange being flat at all points eliminating rocking which could potentially pull insert out of hose. There is one or more pins on the hose side of the outer flange which fit between the ribs on the outside surface of the hose. This eliminates rotation of the insert keeping the insert secure. The inside flange is introduced through the hose wall and seals on the inside. An adhesive\sealant may be used to seal any small cracks between the shaft that penetrates the hose and the hose, but in most applications such sealant may not be required. The shaft is hollow and conducts air from the inside of the hose to the outside or the reverse if used negatively. The bottom of the insert is pointed with gradually tapering sides to allow the insert to be pushed through the hose. In this cone area, there is a scoop which points toward air source or toward the vacuum source if used negatively. This scoop is designed to re-direct air while minimizing friction. The scoop is connected to the hollow shaft and communicates with the distal end of the insert.
Hardwood Floors
[0035] The present invention also provides an improved system for drying floors, and especially hardwood floors. In accordance with the invention, the system contains one or more plates for use with a grid. The plates are designed to go on top of the grid after the floor is prepared. The system, in a preferred embodiment are best used in areas of approximately 50 square feet.
[0036] In accordance with the invention, each wet area may be taped off separately and a separate plate used in each area. The system may be installed to avoid the potential floor traffic and minimize trip hazards. For example, it is usually best to put the plates on the sides of a hall next to a wall. In a bathroom, you would not set up a plate in front of the wash basin or commode, but probably along a wall out of the way. An effort should be made to cover the bulk of the wet area. In many cases however, the effect of the vacuum will extend beyond the reach of the area covered with grid and plastic sheeting. These areas might be the area beneath the stove and refrigerator. Once the vacuum is turned on, there is a pulling effect that will exert force beyond the grid.
[0037] In accordance with the invention, the wet floor surface is prepared. Generally, this involves some sanding or other treatment to remove or otherwise penetrate varnish or other floor sealant that will prevent or retard the air and water movement. This step is not necessary however, and depends on conditions.
[0038] Next, the grid is laid on the floor. The grid is comprised of at least two planes, each plane comprised of generally parallel rows of strands of material, but each plane's rows being not parallel relative the rows of the adjacent plane. Each plane is also parallel to the plane of the floor to be dried. Thus, while a preferred embodiment will be described below, the essential feature of the grid is that it is configured such that air and water may pass between the two planes. Thus, for example, a grid that is uniplanar and is comprised of perpendicular strands which create cells, would generally not be appropriate as it would not permit the movement of air and water from the floor below the grid to the top of the grid.
[0039] Next, atop the grid is placed a special vacuum plate. On the top of the plate will be barbs that will penetrate the plastic sheeting or other membrane. The perimeter is then sealed with convenient sealing means, such as with 2″ wide painter's tape. This type of tape is preferred as it will not harm the wood finish. If sanding is to be done, lesser expensive masking tape may be used.
[0040] The next step will be to set up a blower, such as an Injectidry HP 60 or 90, set on the suction side (negative pressure mode). Next, the tubes are connected from the standard blower to the barbs on the vacuum plates. When the system is thus set up, the blower is activated, and the covered floor area will begin drying. In appearance, the system will resemble a “shrink wrapped” floor section. Importantly, because of the configuration of the grid and the vacuum plate, the impermeable membrane such as visqueen, although taped or otherwise sealed around its perimeter, and compressed by negative pressure against the grid, will not prevent the migration of air or water from the floor, up through the two planes of the grid, into the vacuum plate and thence out through the tubes to the blower. While this system is effective at drying floors, it is also useful in removing excess moisture entrapped in fiberglass or wooden boat hulls.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
[0042] FIG. 1 is an illustration of a prior configuration;
[0043] FIG. 2 is an illustration of the general configuration of the active hoseline feature of the present invention;
[0044] FIG. 3A is side view of the active hoseline feature of the invention, showing two inserts installed therein;
[0045] FIG. 3B is a cross sectional side view of the insert oriented 90 degrees from the view of FIG. 3A , or as seen from the perspective of viewing along the direction of the active hoseline;
[0046] FIG. 3C is a cross section view of the insert inserted into the active hoseline, and oriented the same as FIG. 3B ;
[0047] FIG. 3D is cross section view of the insert oriented the same as the inserts shown installed in FIG. 3A , and 90 degrees from that shown in FIGS. 3B and 3C ;
[0048] FIGS. 4A and 4B are side views, and cross section top views, respectively, of the improved injector feature of the invention;
[0049] FIGS. 5A-5E are illustrations of the floor drying system feature of the invention;
[0050] FIGS. 6A and 6B are side and end views, respectively, of the floor plate of the floor drying aspect of the invention, and FIG. 6C is a cross-sectional detail of the grid of the floor drying aspect of the invention, and FIG. 6D is a top-view detail of a section of the same grid; and
[0051] FIG. 7 illustrates in cross-section the membrane, grid, and manifold.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0052] FIG. 1 is not an aspect of the present invention, but is useful in illustrating the configuration of my prior invention as set forth in U.S. patent application Ser. No. 08/890,141. It is also useful in understanding certain aspects and advantages of the active hoseline feature of present invention.
[0053] FIG. 2 does not show the details of the active hoseline feature of the present invention, but does illustrate the general configuration and context for the subsequent figures and description of the invention. It will be appreciated that while the tubes 10 of FIG. 2 are of uniform and short relatively short length, and uniform frequency along hose 12 for drying wall 16 just above baseboard 14 , tubes 10 can be of any length, or of any frequency of distribution, regular or irregular, along hose 12 . For example, in some applications it may be desirable for alternate tubes 10 to be long enough to reach a ceiling above the wall 16 . In many applications, the preferred frequency of tube distribution along hose 12 will be 8 inches, such that two tubes 10 can be supplied between each wall cavity, such wall cavities (formed by studs within the wall) generally being approximately 16 inches wide along the length of wall 16 .
[0054] Referring now to FIG. 3 , it will be seen in FIG. 3A that hose 12 will generally be corrugated or ribbed and thus have grooves 18 between each corrugation. Typically the corrugation will be spiral along the entire length of hose 12 , but it need not be, and indeed the corrugation is only a typical feature of most hoses, but is not required for the practice of the invention. (Where the hose 12 is not corrugated, the means for preventing rotation of the insert 20 will differ from that described below). Hoseline 12 is penetrated in FIG. 3A by two inserts 20 . Inserts 20 are for receiving and connecting to tubes 10 shown in FIG. 1 and as hereafter described.
[0055] FIG. 3B shows a cross section of insert 20 (typical). Insert 20 is comprised of a piercing point 22 , an air scoop 24 adjacent the piercing point 22 and affixed to a hollow shaft 26 . Circumferentially about hollow shaft 26 is a barbed nozzle 28 for insertion into tube 10 from FIG. 2 . Between barbed nozzle 28 and air scoop 24 along and also circumferentially about hollow shaft 26 is a sealing flange 30 having a curved underside 32 and posts 34 . Posts 34 are designed and configured to fit within grooves 18 of hose 12 , so as to prevent rotation of insert 20 once inserted into hose 12 . While a pair of opposing posts 34 are shown in FIG. 3B , it will be appreciated that only one such post 34 , or any other number of such posts may be provided without departing from the spirit and scope of the invention. Similarly, if hose 12 is not corrugated, and thus lacks grooves 18 , posts 34 may be sharper, shorter and more numerous than shown, and thereby prevent rotation by partially piercing the outer surface of hose 12 , or may be prevented from rotation by suction, adhesive, friction or by any other means.
[0056] Curved underside 32 of sealing flange 30 has a curvature matching the curvature of the outside diameter of hose 12 so as to facilitate sealing to prevent air passage where insert 20 penetrates hose 12 (except of course through hollow shaft 26 as intended). While such curvature is advantageous, and is an inventive aspect, it will be appreciated that it need not be curved, and that such curvature is not essential to the practice of the invention. Similarly, in some applications adhesive may be used to facilitate a seal between insert 20 and hose 12 , but adhesive is not required. For example, in the preferred embodiment, it is anticipated that air scoop 24 will have an inside sealing flange 36 opposite piercing point 22 that will seat against the inner diameter of hose 12 so as to provide a seal. In most embodiments, hose 12 will have a smooth curved surface, even if hose 12 is corrugated on the outside, such that a corresponding curvature may be supplied on inside sealing flange 36 . However, it will be appreciated that the seal may be accomplished by any means, and that such corresponding curvature is not required to practice the invention, and that hose 12 may be of any type.
[0057] In the preferred embodiment, insert 20 is oriented such that air scoop 24 is facing toward the blower, or parallel with the air flow direction within hose 12 . This orientation is shown in FIG. 3C , and will generally result in greater efficiency of the system. However, in alternate embodiments, alternate orientation may be desired. Note that FIG. 3C and FIG. 3B are oriented in the same way, and 90 degrees different from the orientation of FIG. 3A . Thus, in the depicted embodiment, posts 34 straddle part of the circumference of hose 12 at the same point along the length of hose 12 . While this arrangement has certain advantages, it will be appreciated that post or posts 34 may be provided anywhere on curved underside 32 , and may fit within any groove or grooves 18 in accordance with the invention. Furthermore, posts 18 may be eliminated altogether in applications where prevention of rotation of insert 20 is not required or desired. For example, in some applications it may be desirable to permit easy rotation of insert 20 to adjust the air flow captured or routed by air scoop 24 . In most embodiments however, it will be desirable to prevent such rotation.
[0058] In the preferred embodiment, piercing point 22 will be sharp enough and hard enough enable puncturing and penetration of hose 12 simply by grasping insert 20 by hand and pushing it through hose 12 . Such configuration eliminates the need for tools in the field when additional inserts are required or desired. However, it will be appreciated that in some applications it will be desirable to construct the insert with material or of a shape that will require tools for such penetration, without departing from the scope of the invention.
[0059] It will be appreciated that the length of hollow shaft 26 between curved underside 32 and sealing flange 36 will generally be the same as the thickness of the wall of hose 12 , and perhaps slightly shorter so as to squeeze the hose somewhat for a superior seal.
[0060] In the depicted embodiment, it will be seen that sealing flange 36 is configured so as to prevent easy removal of the insert 20 from the hose 12 . However, in some embodiments, it may be preferable to taper or curve sealing flange 36 so that removal is easier.
[0061] In the depicted embodiment, barbed nozzle 28 is barbed so as to facilitate a frictional seal between insert 20 and tubes 10 (not shown in FIG. 3 , but shown in FIGS. 1 and 2 .) However, it will be appreciated that barbed nozzle 28 need not be barbed as shown, nor even be sealed frictionally to to tube 10 , but may be configured in any manner to facilitate a substantial seal between the tube 10 and the insert 20 . Indeed, in some applications it may be preferable to not effect any such seal, but it is anticipated that a seal will generally be preferable.
[0062] FIG. 3D shows a cross-sectional side view of insert 20 . The dotted lines therein depict the interior of hollow shaft 26 , through which air passes in operation of the invention.
[0063] FIG. 4 depicts the improved injector feature of the invention. FIG. 4A is a side view if improved injector 40 . Injector 40 has a barbed nozzle 42 similar to the barbed nozzle 28 of FIG. 3 . Thus, tubes 10 typically connect to barbed nozzle 28 of FIG. 3 on one end and barbed nozzle 42 of FIG. 4 on the other end. In this manner, dry air is blown from the blower through hose to the wet cavity through the tube 10 and injector 40 (in positive pressure mode), or conversely, wet air is sucked from the wet cavity through the injector 40 and tube 10 to the hose, and then to to the blower (in negative pressure mode). As with barbed nozzle 28 , in the preferred embodiment barbed nozzle 42 may be configured in any manner to effect a substantial seal with tube 10 .
[0064] Adjacent barbed nozzle 42 is a tube flange 44 for further facilitating a seal between tube 10 and injector 40 . While tube flange 44 is a feature of the preferred embodiment, it will be appreciated that it is not required for the practice of the invention.
[0065] Adjacent tube flange 44 (or adjacent barbed nozzle 42 if a tube flange 44 is not used), is a barbed connector nozzle 46 for connecting another tube 10 to the injector when the injector 40 is used only as a connector, and not as an injector. That is, a feature of the improved injector 40 is that it can be used as a connector between tubes 10 as well as serving as an injector. This dual purpose or function of improved injector 40 is a significant improvement over prior systems. It facilitates improved versatility and convenience in the field. The connector mode may be useful, for example, when a longer tube is desired at a particular point along the hose. A second tube can simply be attached to the first one by slipping it over the injector 40 , and seating it along the barbed connector nozzle 46 .
[0066] Another inventive aspect of the improved injector 40 is the locking mechanism 50 . Locking mechanism 50 is comprised of one or more flexible tabs 52 , which, when compressed into injector 40 , do not add any dimension to the diameter or outside width of injector 50 , but when released, expand the effective diameter or outside width of injector 40 so as to retard or prevent unwanted withdrawal of injector 40 from the wall or ceiling (or other) hole into which it is inserted for drying of a wet structural cavity.
[0067] In the preferred embodiment, a pair of flexible tabs 52 , as shown in FIG. 4B , are arranged opposite one another such that the user can easily grasp the pair between forefinger and thumb, and thereby insert the injector 40 into the hole in the structure enclosing the wet cavity to be dried. However, it will be appreciated that any number of flexible tabs (even merely one), can be used without departing from the spirit and scope of the invention. Similarly, while in the preferred embodiment the means for effecting the expansion of the tabs beyond the diameter or outside width of the injector 40 is the flexibility of the tabs, molded out of plastic to spring outward from the injector, it will be appreciated that the expansion may be accomplished by other means, such as with a spring. In any case, unlike present systems, the friction is effected behind the wall or ceiling (typically where aesthetics are not a concern), and the withdrawal prevention can be effected with a much smaller hole than otherwise. Moreover, unlike prior friction-based withdrawal prevention systems, the removal can be effected completely non-destructively, simply by squeezing the flexible tabs 52 together into the injector 40 .
[0068] An additional inventive feature of the present invention is the improved means for preventing clogging or plugging. Referring again to FIG. 4A , it will be seen that injector 40 has at its end opposite barbed flange 42 a slot 60 . Slot 60 is an improvement over prior systems in that it is less amenable to plugging than is the relief valve hole of prior systems designed to create a Bernoulli effect. Thus, in addition to a hole at the end of the injector (not shown), which is the means of prior systems to remove wet air or insert dry air, the present injector has a slot 60 along the side of the injector as an alternate route for the air to move should the end hole of the injector ever clog or plug.
[0069] While injector 40 is shown as being substantially straight, it will be appreciated that it may be slightly or substantially curved, as that may be desirable in certain applications, without departing from the spirit and scope of the invention.
[0070] In the currently preferred embodiment, injector 40 is approximately 2 inches in overall length, and approximately {fraction (3/16)} inch in outside diameter on the injector end (that is, the end that is inserted into the wet cavity, as opposed to the barbed nozzle 42 end for receiving the tube 10 ). However, it will be appreciated that even smaller, or if desired, larger diameter injectors are possible. Similarly, while it is generally preferred that the injector 40 be generally tubular, that is round in cross sectional end view, it need not be so. It could be a square tube, triangular tube, octagonal tube, or any shape permitting the passage of air.
Floor Drying System
[0071] The floor drying aspect of the invention will now be described. While the previous aspects of the invention can be used to dry floors, the following aspect of the new system is particularly advantageous in drying floors, especially hardwood floors. Referring now to FIGS. 5A-5E , what is illustrated is the general method of the new system for drying floors, using the components described in greater detail in FIG. 6 . Specifically, FIG. 5A shows the grid 78 laid on the wet floor 56 with a floor plate 70 thereon, and both covered with the impermeable membrane 60 . This membrane is sealed around its perimeter with tape 64 , and is being pierced just above the barbed nozzles 72 of the floor plate 70 . FIG. 5B shows the membrane fitted neatly over the barbed nozzles 72 of the floor plate. FIG. 5C shows two floor plates resting on the grid. FIG. 5D shows the tape being used to seal the membrane over the floor plate and grid. FIG. 5E shows tubes affixed to barbed nozzles of the floor plate, with the tubes off the page being connected to a manifold or hose to the blower, and illustrating the system ready to begin drying in negative pressure mode.
[0072] FIG. 7 illustrates in cross-section the arrangement of the membrane, floor plate, and the strands of the grid. The grid 78 (enclosed dashed oval inset) is shown with superimposing stands 80 and 82 . The grid 78 is placed on the floor 56 (large dashed line). The floor plate 70 is placed over the grid 78 . The membrane 60 is shown covering the floor plate 70 , circumscribing the nozzle 72 , and covering and extending over the grid 78 . along the periphery of the membrande 60 , tape 64 secures the membrande 60 to the floor 56 .
[0073] Referring now to FIG. 6 , floor plate 70 (12 inch version shown) has a plurality of barbed nozzles 72 for receiving tubing from the hose and blower system previously described. Floor plate 70 is shown in end view in FIG. 6B . Floor plate 70 has side walls 74 which raise floor plate off of the grid by a dimension 76 . Dimension 76 is anticipated to be approximately ½ inch, but can be any dimension sufficient to permit air to pass under floor plate 70 and out through barbed nozzles 72 (which are hollow, and connect with tubes 10 as do barbed nozzles 28 and 42 previously described).
[0074] Floor plate 70 depicted in FIGS. 5A-5E , and in FIGS. 6A and 6B , rests upon the grid 78 shown in FIG. 6C and 6D . Grid 78 is comprised of roughly parallel upper strands 80 in one plane superimposed over another set of roughly parallel lower strands 82 in a lower plane. While the strands 82 are roughly parallel with other strands 82 , and the strands 80 are roughly parallel with the other strands 80 , strands 80 and 82 are not parallel with each other such that, as shown in FIG. 6D , a lattice-work type formation is created. The precise angle of orientation of the strands 80 and 82 relative to each other is not critical. All that is critical for this aspect of the invention is that air and moisture are able to pass from one plane to the other. That is, the purpose of grid 78 is to provide a space between the impermeable membrane (not shown) which is laid over the grid and the wet floor through which air and moisture may pass, even when the negative pressure is exerted against the membrane. (In positive pressure mode, no grid is required, but more care must be taken that the perimeter is sealed).
[0075] Now that the details of the particular components of the floor drying system have been described, a general description of the use of the system is provided. Reference to FIGS. 5A-5E may again be helpful here.
[0076] In the preferred embodiment, the grid 78 is either 300 square feet (in the 60 Pak) and 450 square feet (in the 90 Pak). This grid is 30 inches wide. To make handling easier, one way to use it is to cut it into 3 foot long pieces. When covering a wet area with the grid, the user simply places on the floor enough pieces to cover the affected area to be dried. The grid is irregular enough to allow air and moisture to travel up vertically and then horizontally as there is not a perfect seal between the grid and the floor surface.
[0077] In the preferred method of use, painter's tape is specified as it will not remove finish from the floor when removed. Three or four mil plastic sheeting is recommended as the impermeable membrane because of its ease of handing and use. It is also tough enough to allow foot traffic when system setup is completed.
[0078] Floors that can be effectively dried include hardwood, plaster walls with wet door headers, quarry tile, marble, and other surfaces that include grout which can allow moisture to penetrate beneath the surface.
[0079] The mechanics and steps are as follows:
[0080] Apply special grid 78 to the wet area. This is an irregular grid designed to let moisture and air travel vertically and horizontally between two sealing surfaces. The one surface obviously is the hardwood and the next covering layer will be 3-4 mil plastic sheeting.
[0081] Apply a special vacuum plate 70 on top of the grid. On the top of the plate will be barbed nozzles 72 that will penetrate the plastic sheeting.
[0082] The perimeter will be sealed with 2″ wide painter's tape. This type of tape is preferred as it will not harm the wood finish. If sanding is to be done, lesser expensive masking tape may be used.
[0083] The next step will be to set up blowers such as an Injectidry HP 60 or 90 set on the suction side (negative pressure mode). Next, connect the tubes from the standard Injectidry manifolds to the barbed nozzles 72 on the floor plates 70 . When the system is set up, turn on the HP drying system and the floor will be appear to be “shrink wrapped”.
[0084] In the preferred method of use, some of the finish should be removed prior to drying, using a 3M® type floor stripping pads disk beneath a buffer or use fine sandpaper taking care to not take off more than just a little of the finish. No preparatory aggressive sanding should be done unless sanding and refinishing are to be done on completion. If you do not remove some of the finish, however, the drying may not occur very quickly.
[0085] The subfloor must be dried for effective results. If there is a crawlspace, inspect, pull down wet insulation and dry using air movement and dehumidification. If moisture is not removed to equilibrium, the would floor will most likely gain this excess moisture and cup. If the underside is a finished room, a second HP 60 or 90 can be set up to dry through the ceiling. This will dry the subfloor. Moisture readings of all surface material including subfloor will be the only way to determine dry. In preferred usage, jobs should be monitored daily. Some jobs can literally dry overnight, especially if finish is removed, and over-drying can damage the floor.
[0086] While the preferred usage is for hardwoods, other floors such as tile, slate floors, concrete and other semi-permeable hard surfaces can be dried using the system. Summary of steps in the preferred method of the system:
[0087] Step 1: Determine the area that has elevated moisture content.
[0088] Step 2: Might include the initial partial removal of finish in selected areas by light sanding or chemical stripping.
[0089] Step 3: Place the grid over the damp area.
[0090] Step 4: Place a floor plate over the grid out of the traffic area.
[0091] Step 5: Place 3 or 4 mil visqueen over the wet area and over the grid and plate (such a Vac-It Plate® available from Injectidry®).
[0092] Step 6: Seal around the edges with tape. If no sanding is anticipated, releasable painters tape should be used. Otherwise, masking tape may be used. This will seal the visqueen to the surface to be treated.
[0093] Step 7: Connect tubes to Vac-It Plate and connect tubing to vacuum means.
[0094] Step 8: Apply vacuum.
[0095] Step 9: Monitor and stop drying when equilibrium is reached.
[0096] Step 10: Remove grid and evaluate for any further work.
[0097] Objective is to remove moisture faster than the standard method of letting the wet material dry out naturally, or by merely blowing air over the surface, or by puncturing the floor with holes. Further objective is to provide lower pressure point to induce moisture to move toward lower pressure.
[0098] The basic components of the system in its preferred embodiment include:
[0099] Irregular extruded grid to allow air and moisture to move vertically and laterally between two surfaces, one flat and firm and the other conforming to grid surface (e.g. visqueen).
[0100] Vacuum plate that is tunnel shaped that conforms to grid, sealable with the visqueen. Plate is to have vacuum attachment points
[0101] Vacuum means of 40+ inches of water lift
[0102] Plastic sealing such as 4 mil visqueen
[0103] While the preferred embodiment of most of the components of the described system will be constructed of plastic, it may be made of many materials known to those of ordinary skill in the art.
[0104] The foregoing embodiment is merely illustrative of the use or implementation of but one of several variations or embodiments of the invention. While a preferred embodiment of the invention has been illustrated and described with reference to preferred embodiments thereof, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.
[0105] For example, while the system contemplates that the inserts in the active hoseline may be added by users at will, it is contemplated that the preferred embodiment will be sold as a completely pre-configured system, such that no inserts need to be installed by the user, and that the inserts will be essentially permanent for durability.
[0106] While the preferred embodiment contemplates that the inserts may be inserted easily by hand, in some applications it may be preferable that insertion and/or removal of the inserts will require tools. Also, in the preferred embodiment, it is anticipated that the removal of the insert will not leave a hole in the hose, but that the hole into which it was place previously will essentially reseal upon removal of the insert.
[0107] In the preferred embodiment, the inserts for the tubes will be spaced every eight inches. However any frequency, regular or irregular, may be practiced without departing from the invention. Similarly, in the preferred embodiment, hoses will come in ten foot standard lengths. However, any length of hose may be provided, as well as any length of tube. An advantage of the invention is that manifolds (such as that of my prior system) are not required. However, a manifold may still be used with the invention.
[0108] The invention may be practiced with the hoses terminating, or a forming a complete circuit back to the blower, and with any number of blowers. Similarly, either positive or negative pressure may be used with the system. This decision will be dictated by conditions or goals. | The invention provides an improved method of drying wet or water damaged surfaces using a vacuum source, a manifold, and a plastic sheet covered grid having a lattice formation with spaces to permit the passing of moisture and air from and beneath the surface to the vacuum source. | 5 |
FIELD OF THE INVENTION
The invention relates to food ingredients obtained by fermentation with Saccharomyces boulardii yeast and to foods containing them.
BACKGROUND OF THE INVENTION
Yeasts of the genus Saccharomyces are commonly used in many agricultural food industries.
Nevertheless, each agricultural food industry utilizes Saccharomyces species in a very specialized manner for the production of fermented foods or drinks.
Thus, S. cerevisiae is used in bakery.
S. cerevisiae, S. carlsbergensis or S. uvarumare yeasts employed in beer production. S. uvarum is also used in cider making.
S. cerevisiae var. ellipsoideus, S. beticus and S. bayanus are well-known yeasts for wine fermentation.
S. rouxii is employed in the manufacture of soya sauces and also for rice miso.
S. boulardii is a yeast which was isolated from lychee fruits from Indochina back in the 1920s. Since 1962, S. boulardii has been used in Europe and other countries as a probiotic medicinal product having an antidiarrhoeal effect in man. Thus, S. boulardii forms the active principle of the pharmaceutical speciality Ultra-Levure, trade name of Laboratoires Biocodex (92 126--Montrouge, France).
Several patents teach us that S. boulardii is an effective medicinal product against some diseases of man: EP-A-0,149,579 and U.S. Pat. No. 4,595,590 for pseudomembranous colitis, EP-A-0,195,870 and U.S. Pat. No. 4,643,897 for amoebiasis.
S. boulardii has never been used in the production of fermented foods or drinks.
SUMMARY OF THE INVENTION
Now, we have discovered that S. boulardii can be used profitably for producing fermented foods and food ingredients, by fermentation of vegetable raw materials containing carbohydrates and proteins.
The non-limiting examples which follow will illustrate the invention.
In these examples, simple foods are fermented after receiving an inoculum containing S. boulardii. The inoculum may be produced by any known technique of yeast culture.
It is possible, for example, to produce the inoculum in the following manner:
500 ml of a culture medium containing 10 g of malt, 1 g of maltose, 1 g of commercial yeast extract (Bio Merieux, 69260 Charbonnieres-les-Bains, France) and 500 ml of distilled water are introduced into a flask. The flask is closed with a stopper having two Pasteur pipettes inserted through it, after which the assembly is sterilized at 120° C. for 10 minutes. After cooling to room temperature, the medium is inoculated with 2.5×10 9 live S. boulardii yeast cells. One of the two Pasteur pipettes is connected via its outer end to a tube leading to an aeration pump, and emits bubbles into the culture medium via its inner end. The other pipette does not dip into the culture medium and enables gases to be discharged. The assembly is then placed in an incubator at 37° C. After 48 hours, the culture containing S. boulardii is centrifuged at 4000 rpm for 5 minutes. The supernatant is removed and the pellet is taken up in 30 ml of distilled water. This suspension constitutes the inoculum. The concentration of the inoculum is, on average, 10 9 yeast cells per milliliter.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
EXAMPLE 1
The following products are introduced into a dough mill of capacity 2 liters having thermostated walls:
______________________________________Ground raw wheat 1 kgProtein hydrolysate (Keramine A, trade name 50 mlof Bretagne Chimie Fine, 56140 - Pleucadeuc,France)Glucose 100 gWater 450 mlInoculum 30 ml______________________________________
The temperature of the mill is adjusted to 37° C. The beater of the mill is rotated at 50 rpm for 15 minutes every hour. Water is added during the fermentation in order to maintain the relative humidity above 90% (the relative humidity is measured with a Thermoconstanter, trade name of Novasina A. G., Zurich, Switzerland, hygrometer).
After 48 hours of fermentation, the characteristics of the fermented wheat are analysed according to the analytical methods commonly used in the EEC. The wheat thus fermented is compared with the original raw wheat and with the raw wheat mixed with the ingredients, such as the protein hydrolysate, glucose and water, in the same proportions as those used for the fermentation.
The results show that S. boulardii has modified the organoleptic, physical and chemical characteristics of the wheat after fermentation:
______________________________________ Raw Wheat Original wheat + fermented raw ingre- with S. wheat dients boulardii______________________________________Odour of Cereal Cereal Fresh breadpH (1 g in 10 ml of 6.30 6.20 5.45demineralized water)Dry matter (D.M.) (%) 85.7 57.3 77.7Sucrose (% D.M.) 1.2 1.4 0Proteins (% D.M.) 13.6 13.7 15.0Live yeast cells/g 0 0 3 × 10.sup.7D.M.______________________________________
EXAMPLE 2
In the same dough mill as in Example 1, adjusted to 37° C., the following products are mixed:
______________________________________Soya cake 1 kgGlucose 100 gWater 300 mlInoculum 30 ml______________________________________
The beater of the mill is rotated at 50 rpm for 15 minutes every hour for 36 hours.
Water is added regularly in order to maintain the relative humidity of the mixture at a level in the region of 90%.
After 36 hours, the analyses show that the fermentation with S. boulardii has modified the organoleptic, physical and chemical characteristics of the soya cake:
______________________________________ Original Fermented soya cake soya cake______________________________________Odour of Soya cake Yeast pastrypH (1 g in 10 ml of 6.65 6.33demineralized water)Dry matter (D.M.) (%) 86.6 58.4Starch (% D.M.) 9.0 4.6Total sugars (% D.M.) 10.2 2.6Sucrose (% D.M.) 5.2 0Proteins (% D.M.) 50.9 53.6Live yeast cells/g D.M. 0 3.2 × 10.sup.7______________________________________
EXAMPLE 3
In the same dough mill as in the previous examples, adjusted to 37° C. the following products are mixed:
______________________________________Cereal (50% wheat/50% maize) flakes 1 kgProtein hydrolysate (Keramine A, trade name) 50 mlGlucose 20 gWater 400 mlInoculum 30 ml______________________________________
The beater is rotated at 50 rpm for 15 minutes every hour for 48 hours. Water is added regularly so as to maintain the relative humidity at 90%.
After 48 hours, it is found by analysis that fermentation with S. boulardii has modified the organoleptic, physical and chemical characteristics of the cereal flakes:
______________________________________ Original Fermented cereal cereal flakes flakes______________________________________Odour Neutral of Fresh breadpH (1 g in 10 ml of 6.60 6.00demineralized water)Dry matter (D.M.) (%) 88.7 60.0Proteins (% D.M.) 13.0 15.1Sucrose (% D.M.) 1.2 0Live yeast cells/g D.M. 0 1.35 × 10.sup.8______________________________________
EXAMPLE 4
In the same dough mill as in the previous examples, thermostated at 37° C., the following products are mixed:
______________________________________Ground pea 500 gGlucose 10 gYeast extract (BioMerieux) 10 gWater 150 mlInoculum 20 ml______________________________________
The beater of the mill is rotated at 50 rpm for 15 minutes every hour for 30 hours.
Water is added regularly in order to maintain the relative humidity of the mixture at a level in the region of 90%.
After the fermentation, the analyses show that S. boulardii has modified the organoleptic, physical and chemical characteristics of the pea:
______________________________________ Original Fermented pea pea______________________________________Odour of Bean Slightly alcoholicpH (1 g in 10 ml of 6.48 5.21demineralized water)Dry matter (D.M.) (%) 86.7 65.8Proteins (% D.M.) 23.6 25.2Sucrose (% D.M.) 2.2 0Live yeast cells/g D.M. 0 2.29 × 10.sup.7______________________________________
EXAMPLE 5
In the same dough mill as in the previous examples, adjusted to 37° C., the following products are mixed:
______________________________________Cassava flour 500 gGlucose 10 gYeast extract (BioMerieux) 10 gWater 300 mlInoculum 30 ml______________________________________
The beater of the mill is rotated at 50 rpm for 15 minutes every hour for 46 hours.
Water is added regularly so as to maintain the relative humidity of the mixture at a level in the region of 90%.
After the fermentation, the analyses show that S. boulardii has modified the organoleptic, physical and chemical characteristics of the cassava:
______________________________________ Original Fermented cassava cassava______________________________________Odour Neutral AcidicpH (1 g in 10 ml of 6.40 4.60demineralized water)Dry matter (D.M.) (%) 86.6 55.7Proteins (% D.M.) 2.1 3.2Live yeast cells/g D.M. 0 1.1 × 10.sup.8______________________________________ | The invention relates to food ingredients obtained by fermentation of raw materials of vegetable origin with Saccharomyces boulardii yeast, and to foods containing them. | 0 |
BACKGROUND OF THE INVENTION
A. Field of the Invention
The present invention relates generally to the field of windshield wiper control systems and more particularly to a windshield wiper control system that provides a selectable and continuously variable delay interval between successive windshield wiper sweeps and that may be utilized in conjunction with a conventional wiper switch as provided by the manufacturer of an automobile with the conventional wiper switch operating independently of the variable delay windshield wiper control system.
B. Background of the Invention
Various windshield wiper control system arrangements of the prior art provide intermittent or variable speed operation of the windshield wiper system as provided by the manufacturer of an automobile. In these arrangements the speed of the windshield wipers or the delay time between successive wiper sweeps is varied under the control of an operator by the use of numerous electrical circuit arrangements.
A first type of windshield wiper control system that has a single wiper control switch and that utilizes a switching circuit in combination with a delay time circuit and a timing termination circuit is described in U.S. Pat. No. 3,492,558 which issued to R. K. Patterson, Jr. et al, on Jan. 27, 1970. This control system is effective to activate the switching circuit when the ignition switch is operated and to provide an initial sweep of the wipers when the single wiper control switch is activated. Thereafter, the timing circuit determines the delay time between successive operations or sweeps of the wipers as it charges up a timing termination circuit turns off the system after actuation of the wiper mechanism.
Another type of windshield wiper control system of the prior art described in U.S. Pat. No. 3,780,367 which issued to W. D. Holt on Dec. 18, 1973, utilizes a single wiper control switch, a variable delay timing circuit and a washer-initial sweep circuit. The single control switch is arranged to have positions corresponding to an off or nonoperating mode, a slow position, a fast position and an intermittent position. When the control switch is rotated from the off position to the intermittent position, a momentary contact is established to actuate the washer and the initial sweep circuit which includes a timing capacitor that produces several sweep operations of the wiper mechanism during the timing or discharge of the capacitor through a first relay in the washer-initial sweep circuit. As the control switch is fully rotated to the intermittent position, the delay timing circuitry utilizes a second timing capacitor and a second relay to produce successive sweeps spaced apart by a variable selectable delay interval. Both the delay timing circuitry and the initial sweep circuitry have adjustable controls to vary the number of initial sweeps and the delay time between successive sweeps in the intermittent position.
Other types of windshield wiper control circuits utilizing various types of time delay circuitry are described in the following U.S. Pat. Nos.: 3,581,178; 3,564,374, 3,219,901; 3,262,042, 3,353,079; 3,335,352; 3,364,410; and 3,483,459.
While the windshield wiper control arrangements of the prior art as discussed and referenced hereinabove are generally suitable for their intended purpose, they involve either complicated arrangements to provide initial operation of the wiper control system upon actuation in the intermittent or variable delay mode, or no provision for an immediate wiper sweep upon actuation of the wiper control system in the intermittent mode.
Further, the windshield wiper control systems of the prior art are not generally suitable for use in conjunction with the conventional wiper switch supplied by the manufacturer of the automobile. These prior art arrangements generally contemplate the replacement of the original equipment wiper control switch or the installation of the overall wiper control system as original equipment. Thus, the conventional wiper control switch provided as original equipment is not generally capable of operation independently of the intermittent wiper control system.
SUMMARY OF THE INVENTION
Accordingly, it is a principal object of the present invention to provide a variable delay windshield wiper control system arrangement which avoids one or more of the above described disadvantages of the prior art.
Another object of the present invention is a variable delay windshield wiper control system that provides an immediate wiper sweep cycle upon actuation of the control system in a simple manner by either initialization of a time delay circuit or by a variable delay control switch that directly effects operation of the conventional wiper drive source; the operation of the variable delay wiper control system being independent of the conventional original equipment wiper switch.
A further object of the present invention is a variable delay windshield wiper control system for variable speed operation that provides a delay between successive wiper cycles under light precipitation conditions to prevent streaking or dry operation of the wiper blades and that is easily connected in an after-market fashion to conventional wiper control systems provided as OEM (original equipment manufacturer) equipment by an automobile manufacturer; the conventional wiper switch provided as OEM equipment being operable independently of the variable delay speed wiper control system.
A further object of the present invention is a selectable delay windshield wiper control system which is inexpensive in its manufacture and does not duplicate the provisions and operations of the conventional OEM wiper control and wiper switch arrangements.
Briefly in accordance with the present invention, a variable delay windshield wiper control system is provided for selectively effecting operation of a conventional electrical drive source and a wiper drive mechanism for a wiper blade at predetermined variable intervals and with a selectable variable delay between successive wiper cycles.
The variable delay windshield wiper control system includes a timing circuit for generating variable duration intervals and effecting operation of the conventional electrical drive source at the end of each of the intervals. A delay control device is connected to the timing circuitry for determining the duration of the variable intervals and the delay between successive wiper cycles and is continuously variable between a minimum and maximum position. Further, a control device is provided that controls the operation of the timing circuitry and directly effects operation of the conventional electrical drive source upon actuation of the control device by an operator from a first position corresponding to the off position to a second position corresponding to an operational state wherein the timing circuitry effects operation of the conventional electrical drive source at a normal operational speed and with the successive wiper cycles being spaced apart by the selectable variable delay.
In a first arrangement, the control device includes a three position-double pole switch wherein one position is a momentary position as the switch is moved from the off to the operational state to thereby provide an immediate first wiper sweep or "instant-on" arrangement upon actuation of the switch. In a second arrangement, the control switch includes an "instant-on" switch which is a momentary contact switch to provide the first immediate sweep and a second double pole-single throw switch to effect operation from the off state to the on state. A third arrangement includes a control switch in a three pole-double throw arrangement which initializes the timing circuitry to provide a first immediate sweep of the wiper blades when the control switch is moved from the off to the on position.
The variable delay windshield wiper control system of the present invention is easily incorporated into the conventional OEM wiper control system of an automobile and operates in conjunction with the conventional wiper switch as provided by the manufacturer so that the conventional wiper switch also operates independently of and overrides the control switch of the variable delay wiper control system. A control panel that attaches to the dashboard of the automobile is provided that carries the control switch and the adjustable delay control.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention both as to its organization and method of operation together with further objects and advantages thereof, will best be understood by reference to the following specification taken in conjunction with the accompanying drawings, in which:
FIG. 1 is an electrical schematic diagram of a conventional OEM windshield wiper system of an automobile and the variable delay windshield wiper control system of the present invention to thereby provide improved windshield wiper control and operational features;
FIG. 2 is an electrical schematic diagram of a conventional OEM windshield wiper drive control arrangement that is suitable to be utilized in connection with the variable delay wiper control arrangement shown in FIG. 1;
FIG. 3 is an electrical schematic diagram of a second conventional OEM wiper drive control arrangement utilized in automobiles and suitable for operation in conjunction with the variable delay wiper control system arrangement of the present invention illustrated in FIG. 1;
FIG. 4 is a pictorial representation of a control panel utilized to control the operation of the variable delay wiper control system of the present invention as shown in FIG. 1;
FIG. 5 is an electrical schematic diagram of a second arrangement of the variable delay wiper control system of the present invention illustrated in conjunction with a conventional OEM wiper drive system; and
FIG. 6 is an electrical schematic diagram of a third arrangement of a variable delay wiper control system in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The variable delay windshield wiper control system of the present invention indicated generally at 10 and referring to FIG. 1 is utilized in conjunction with a conventional OEM windshield wiper system having a wiper drive mechanism 12 such as a gear box which is arranged to move the windshield wiper blades referred to generally at 11 in a reciprocative path or wiper cycle across the windshield of an automobile. The wiper drive mechanism 12 is driven by a wiper drive control arrangement 14 which includes a DC electrical motor and a park switch to operate the wiper drive mechanism 12 and return the wiper blades to the park or home position normally below the windshield when a conventional OEM wiper switch 16 is deactivated by the operator.
The wiper switch arrangement 16 controls the operation of the wiper drive control stage 14 and includes two three position switches operated on a common shaft referred to as a three position-double pole switch wherein a first three position on-off switch 18 controls the actuation of the wiper drive control stage 14 and a second three position switch 20 controls the speed of operation of the wiper blades when the wiper drive control stage 14 is actuated.
A control lead 22 is provided from the wiper drive control stage 14 to the low and high positions of the on-off switch 18 whereby the control lead 22 is connected to a reference potential such as a ground potential 24 of the vehicle electrical system when the switch 18 is in the low or high position and no connection is provided to the control lead 22 when the switch 18 is in the off position. The switch 20 is arranged in the off and low positions to connect a speed control lead 26 of the wiper drive control stage 14 to the ground potential 24 and no connection is made to the speed control lead 26 with the switch 20 in the high position.
A conventional ignition switch arrangement 28 provides a reference potential 30 such as the battery voltage to a switched supply lead 32 of the wiper drive control 14 upon actuation of the ignition switch 28.
The wiper switch 16 controls the operation of the wiper drive control stage 14 to rotate the wiper drive mechanism 12 thereby operating the windshield wiper blades 11 in either a low or high speed mode of operation. The wiper drive control stage 14, referring to FIGS. 2 and 3, includes a DC electrical drive motor 34 having a series field winding 36 and a shunt field winding 38.
In a first conventional arrangement, FIG. 2, the switched ignition voltage 32 is connected to the series winding 36 through the contacts 42 of a park switch and relay arrangement 40 which are in an open condition when the wiper blades are in the parked or home position and in a closed condition when the wiper blades are in any position other than the park position. The contacts 42 are controlled to be closed in the park position when a coil winding 44 of the park switch relay 40 is energized. The relay coil winding 44 is connected between the switched ignition lead 32 and the control lead 22 so that the relay coil 44 is energized whenever the control lead 22 is grounded by the switch 18.
The series field winding 36 of the motor 34 has one end connected to the switched ignition voltage 32 through the contact pair 42 and the other end connected through the armature circuit of the motor 34 to the ground potential so that the motor 34 is energized when the contact pair 42 is closed. The shunt field winding 38 of the motor 34 is connected between the speed control lead 26 and the junction of the series winding 36 and the armature of the motor 34. A shunt field resistor 46 is connected between ground and the junction of the shunt field 38 and the speed control lead 26. This establishes a weakened shunt field whenever the control lead 26 is not connected to ground.
With the switch 20 in the off or low positions, current is provided through the shunt field winding 38 resulting in a low speed operation of the motor 34. The motor 34 operates at a high speed condition when the switch 20 is rotated to the high position so that a small value of current flows through the shunt field winding 38 while normal armature current flows through the series field winding 36.
In a second conventional wiper drive control arrangement and referring to FIG. 3, the series field winding 36 of the motor 34 has one end connected to the switched ignition voltage 32 and the other end connected through the armature circuit of the motor 34 to the control lead 22.
A park switch 48 is provided between ground and the junction of the control lead 22 and the armature circuit of the motor 34 thereby connecting one side of the armature circuit to ground when the park switch is closed. The park switch 48 is open when the wiper blades are in the park position and closed at all other positions of the reciprocative path.
The shunt field winding 38 is connected between the speed control lead 26 and the junction of the series winding 36 and the armature circuit of motor 34 as in the arrangement of FIG. 2. Similarly a shunt field resistor 46 is provided between ground and the junction of the series field winding 36 and the armature circuit of the motor 34.
In this arrangement, FIG. 3, the control of the motor 34 is accomplished by grounding the control lead 22 through the switch 18 wherein the switch contacts of switch 18 carry the full motor current through the series field winding 36 and the armature circuit of the motor 34. As in the arrangement of FIG. 2, the shunt field winding 38 is connected to ground through switch 20 to supply a high shunt field condition resulting in the low speed mode of operation of the motor 34 when the switch 20 is in the off or low position. With switch 20 in the high position, no connection is made to the shunt field winding 38 and high speed operation results.
In accordance with an important aspect of the present invention, the variable delay wiper control system 10 is connected in the conventional OEM windshield wiper system of a vehicle to the switched ignition voltage 32, the wiper drive control lead 22 and the ground reference 24 of the electrical system of the vehicle to provide a selectable variable delay mode of operation of the wiper blades 11 by controlling the wiper drive control 14 independently of the OEM wiper switch 16 at predetermined variable intervals such that the operator may select a variable delay between successive wiper sweeps or cycles.
In the preferred embodiment, the variable delay windshield wiper control system 10 is installed as an after-market feature rather than as OEM equipment, that is, for installation on vehicles after delivery from the manufacturer rather than for installation by the manufacturer on the production line. Thus, the functions of the OEM wiper switch 16 of a vehicle are not duplicated in the variable delay windshield wiper control system 10 and the OEM wiper switch is operable independently of the variable delay arrangement 10. In an alternate embodiment, however, it is contemplated that the variable delay windshield wiper control system 10 may be installed as OEM equipment by the manufacturer and incorporate the function of the conventional wiper switch 16.
When the variable delay wiper control system 10 is operational, the conventional wiper switch 16 may still be operated independently of and overrides the wiper control system 10.
Operation of the variable delay wiper control system 10 is controlled by a switch arrangement indicated generally at 50 which in the arrangement of FIG. 1 is a three position-double pole switch wherein a first position corresponds to the off state of the variable delay wiper control system 10, a second position corresponds to the on or operational state and a third position is a momentary contact position to provide an "instant-on" wiper sweep as will be explained in detail hereinafter. The momentary contact position is obtained either as the switch is moved from the off to the on position in one specific embodiment or as the switch is moved past the on position to the momentary or "instant-on" position and then is automatically returned to the on position.
The three position-double pole switch 50 is a conventional three positon rotary switch in one embodiment operated by a common shaft or a three position slide switch in a preferred specific embodiment, FIGS. 1 and 4, which is operated by a moveable slide actuator and includes a first switch layer 52 and a second switch layer 54. The common terminal 52a of the first switch 52 of the arrangement 50 is connected to the wiper drive control lead 22. A first contact terminal 52b of the switch 52 corresponds to the off position and is an open circuit so that no termination is provided to the control lead 22 in the off position. The switch contact terminal 52c corresponding to the on position of switch 52 is connected to an output control lead 58 of the variable delay wiper control arrangement 10 and a third contact terminal 52d corresponding to the momentary contact position of the switch 52 is connected to the ground potential 24.
The second switch layer 54 of the control switch arrangement 50 has a common terminal 54a which is connected to a voltage supply input 60 of the variable delay windshield wiper control arrangement 10. The off position contact terminal 54b and the momentary contact position terminal 54d of the switch 54 are not utilized and have no connections. The on position contact terminal 54c is connected to the switched ignition voltage 32. Thus, the switched ignition voltage is connected to the voltage supply input 60 when the switch 50 is in the on position.
In a specific embodiment of the switching arrangement 50, a slide switch may be utilized with a single push button or slide actuator which has the off position, on position and momentary "instant-on" contact positions referred to hereinabove arranged from left to right so that the slide actuator may be moved from the off position to the right into the "instant-on" momentary contact position. The switch 50 is provided with a spring-biased arrangement to return the slide actuator to the on position where the slide actuator remains until the operator moves the switch from the on position in a left direction to the off position.
In a specific alternate embodiment, the slide actuator when being moved from the left to the right may have an on position detent wherein the operator can either move the switch from the off to the on position or from the off to the "instant-on" position similarly as above with a spring-biased return arrangement.
In the preferred embodiment, a control panel arrangement 70 is provided, referring to FIG. 4, which is attached to the automobile dashboard at a convenient location for the operator and includes a slide switch arrangement 50 wherein a slide actuator 72 is provided having an off position, an on position and an "instant-on" position as described hereinabove. A delay control 74 is also provided on the control panel 70 which is a rotary control operated by a control knob 76 so that the delay control is rotatable and continuously variable between two stop positions defining the minimum and maximum delay positions obtainable as will be described hereinafter. If a rotary arrangement is utilized for the switch 50, an "instant-on" momentary contact position is also provided with a spring-biased return in a rotary direction.
In accordance with an important aspect of the present invention, the variable delay wiper control arrangement 10 provides output control signals at 58 to activate the wiper drive control stage 14 by means of control lead 22 when the control switch 50 is in the on position. Specifically, an integrated circuit timer 80 is programmed by the variable delay control 74 to generate a control signal output 82 at predetermined intervals. The output 82 of the integrated circuit timer 80 is a low voltage level during a portion of each timing interval and a high voltage level throughout the remainder of each timing interval. The output 82 controls the conductive state of a PNP transistor 84 which is connected to provide a conductive path from the wiper drive control lead 22 to the ground potential.
The integrated circuit timer 80 in a preferred specific embodiment is an SE 555 CV device manufactured by Signetics or an SG 555M available from Silicon General. The integrated circuit timer 80 provides accurate timing intervals by producing a low output level during the time the resistive-capacitive timing circuitry associated with the integrated circuit timer 80 is discharging and a high output level during the interval when the resistive-capacitive circuitry is charging.
Basically, the integrated circuit timer 80 includes two comparators controlling the state of a flip-flop which drives a discharge transistor stage and an output stage. In accordance with the present invention, the timer stage 80 is arranged to operate in an astable mode and free runs as a multivibrator. Specifically, an external timing capacitor 86 is connected at one end to ground and at the other end to the threshold and the trigger inputs of the timer stage 80 through a series resistor 88.
The series combination of two resistors 90 and 92 and a variable resistor 94 of the delay control 74 is connected between the Vcc supply input of the timer 80 and the junction of the timing capacitor 86 and the resistor 88 to form the resistance portion of the resistive-capacitive timing arrangement.
The switched ignition voltage 32 is provided to the voltage supply input 60, with the switch 54 in the on position, and to the reset and the Vcc supply inputs of the timer 80 through a diode 96 (anode to cathode) and a series resistor 98. A zener diode 100 is connected between the Vcc input of the timer 80 and ground to provide a stable reference voltage to the timer stage 80. Two filter capacitors 102 and 104 are connected between the Vcc input of the timer 80 and ground. A filter capacitor 106 is connected between the control lead 108 of the timer 80 and ground to provide a termination to the control input which is not utilized in the preferred embodiment but may be used to vary the internal reference voltage of the timer 80.
In operation the external timing capacitor 86 is charged through timing resistors 90 and 92 and potentiometer 94. When a voltage level at the level sensitive threshold input of the timer 80 reaches approximately two-thirds of the supply voltage Vcc, an internal flip-flop in the timer circuit 80 is reset thereby switching the output 82 to a low state. The output 82 remains at a low state until the level sensitive trigger input is brought below a level which is approximately one-third the supply voltage Vcc thereby setting the flip-flop and returning the output 82 to a high state.
The discharge lead of the timer circuit 80 is connected to the junction of resistors 90 and 92 and is effective when the internal flip-flop is reset and the output state 82 is a low level to provide a discharge path for the external timing capacitor 86 through the series resistor 90. As the capacitor 86 discharges to a level of approximately one-third the Vcc supply voltage, the trigger input is effective to set the flip-flop and return the output 82 to a high-level state as well as disabling the discharge lead. The capacitor 86 is then returned to a charging mode through the resistors 90, 92 and the potentiometer 94. This process continues in an astable mode with alternate charging and discharging of the capacitor 86 with respective durations of high and low level output states at output 82. Thus, variable timing intervals are generated with successive low output states occurring in a periodic, accurately timed manner at the output 82 with the duration of each interval being constant for a specific resistance of the potentiometer 94 and being selectively variable by the setting of the potentiometer 94.
The output 82 of the timer stage 80 is connected to the base lead of the output control transistor 84. The collector of the transistor 84 is connected to ground and the emitter is connected to the output control lead 58 of the variable delay wiper control arrangement 10. The emitter of the transistor 84 is connected to the wiper control lead 22 when the switch 50 is in the on position. When the output 82 is a low level state, the control transistor 84 is switched to a conductive state so as to provide a path to ground for the control lead 22 of the wiper drive control stage 14 which actuates the OEM wiper control system to provide a full reciprocative path of the wiper.
The discharge time of the timer 80 as defined by the resistor 90 and the external capacitor 86 is chosen to provide a low output state at 82 of sufficient duration to actuate the wiper drive control stage 14 to move the wipers from the park position. The duration of the low output state at output 82 is calculated to be shorter than the time for the wipers to complete one reciprocative path or cycle at low speed operation so that only one reciprocative path is provided for each timing interval. In practice, the time duration of the low output state at output 82 is only a small percentage of the time duration for a complete wiper cycle in order to be sufficient to actuate the wiper drive control stage 14 to complete a path.
As the potentiometer 94 is varied from its minimum to maximum positions by the control knob 76 of the delay control arrangement 74, the duration of each interval at the output 82 as defined by the time between successive transitions from a high level state to a low level state is correspondingly varied. Thus, the operator may select a delay between successive wiper cycles of approximately 2 seconds to 30 seconds from the minimum to maximum settings of the potentiometer 94 in a specific embodiment.
In accordance with another important aspect of the present invention, when the switch arrangement 50 is moved from the off position to the "instant-on" position the control lead 22 of the wiper drive control 14 is momentarily grounded through contact 52d for a sufficient time period to energize the wiper drive control stage 14 to complete a reciprocative path or cycle of operation of the wipers. The momentary ground through contact 52d energizes the wiper drive control stage 14 and the cycle is completed by the park switch arrangement 40 of FIG. 2 or 48 of FIG. 3. In this manner, when the operator turns the variable delay wiper control system 10 to the operational or on state, a first immediate wiper cycle will be provided without waiting for the timer arrangement 80 to provide a low output state corresponding to the charging time of capacitor 86.
In a specific embodiment, the following parameters and circuit elements were found to be suitable in practicing the present invention although they should not be interpreted in a limiting sense: capacitor 86, 100 microfarads; resistor 90, 15 Kohms; resistor 92, 33 Kohms; range of potentiometer 94, 0 to 300 Kohms; resistor 88, 1 Megohm; transistor 84, type 2N6111 or equivalent.
For a detailed description of the operation and circuitry of the integrated circuit timer 80, reference may be made to the Signetics data sheets and application notes and also to Chapter 7 of Applications of Linear Integrated Circuits, by Eugene R. Hnatek, published by John Wiley and Sons, 1975.
In accordance with a further important aspect of the present invention and referring to FIG. 5, a second arrangement of the variable delay wiper control system 10 is provided wherein the switching arrangement 50 includes a one position (single pole-single throw) "instant-on" switch 120 and an independently operated one position (double pole-single throw) on-off switch 122. The timing stage 80 and associated control circuitry of the variable delay wiper control arrangement 10 as shown in FIG. 5 is generally similar to that illustrated in FIG. 1 in both arrangement and operation and like reference numerals represent identical components.
The "instant-on" switch 120 is connected between the control lead 22 of the wiper drive control stage 14 and the ground potential 24. In a specific embodiment the switch 120 is a spring-biased momentary contact switch which is actuated by the operator such as by moving a slide actuator toward the right, for example, with a momentary contact being provided and the switch automatically returning to the off or open state. In this way a momentary ground connection is provided to the control lead 22 so as to provide an immediate cycle or "instant-on" operation of the wiper blades 11.
The on-off switch arrangement 122 includes a first one position switch 124 connected between the control lead 22 and the output control lead 58 of the variable delay wiper control arrangement 10 and a second single position switch 126 connected between the switched ignition voltage 32 and the voltage supply input 60 of the arrangement 10. The switches 124 and 126 are arranged to be operated by a common slide actuator wherein switch 122 is a slide switch in a preferred embodiment. In the alternative, the switch 122 may be a rotary switch and the switches 124 and 126 operated by a common shaft.
In this arrangement of the variable delay windshield wiper control arrangement 10, FIG. 5, and in accordance with an important aspect of the present invention, the operator activates the "instant-on" switch 120 to obtain an immediate wiper cycle and also independently moves the switch 122 to the on position to obtain the successive wiper cycles separated by the selected delay time as long as the switch 122 is in the on position. If the operator does not desire to obtain an "instant-on" cycle of the wipers, only switch 122 need be actuated. As in the arrangement of FIG. 1, the variable delay wiper control arrangement 10 with the associated switch arrangement 50 is operated independently of the conventional switch arrangement 16. Similarly the conventional wiper switch 16 can be operated independently of the variable delay wiper control arrangement 10 in either the low or high speed positions of operation and further can be utilized to override the operation of the variable delay wiper control arrangement 10 while the switch 122 is in the on position.
In accordance with yet a further important aspect of the present invention and referring to FIG. 6, a third arrangement of the variable delay wiper control arrangement 10 is illustrated utilizing a switching arrangement 50 of a three pole-double throw configuration which may also be referred to as a three pole two position switch and includes three switches 150, 156 and 158.
The first switch 150 of the switching arrangement 50 has a common terminal 150a which is connected to one end of the timing capacitor 86 that is connected to the junction of resistors 88 and 90 in the arrangements of FIGS. 1 and 5 which may also be referred to as the positive or charging terminal of capacitor 86.
In the arrangement of FIG. 6, the capacitor 86 is not directly connected to the junction of resistors 88 and 90 but instead the junction of the resistors 88 and 90 is connected to the on position terminal 150b of the switch 150. Thus, the junction of resistors 88 and 90 is connected to the charging terminal of capacitor 86 when the switch arrangement 50 is in the on position. The off position terminal 150c of the switch 150 is connected to the junction of two resistors 152 and 154 which are connected in series between the ground potential 24 and an off position terminal 156c of the second switch 156 of the switching arrangement 50. The common terminal 156a of the switch 156 is connected to the switched ignition voltage 32. The switched ignition voltage is, therefore, provided to the resisitive divider arrangement formed by resistors 152 and 154 when the switch 156 is in the off position. The on position terminal 156b of the switch 156 is connected to the voltage supply input 60 of the variable delay wiper control arrangement 10.
The third switch 158 has a common terminal 158a connected to the control lead 22 of the wiper control stage 14 and an on position terminal 158b connected to the output control lead 58 of the variable delay wiper control arrangement 10. There is no connection to the off position terminal 158c of switch 158.
In operation and in accordance with another important aspect of the present invention, the switching arrangement 50 in a preferred specific embodiment is a slide switch configuration wherein the switches 150, 156 and 158 are operated by a common slide actuator or in an alternate embodiment switch 50 is a rotary switch wherein the switches 150, 156 and 158 are two-position switches operated by a common shaft arrangement.
In any case, the operator moves the switching arrangement 50 from the off to the on position with an "instant-on" or immediate cycle of the wiper blades being provided and successive wiper cycles being spaced apart by variable delays as selected by the delay control 74 as discussed hereinabove.
Specifically, with the switching arrangement 50 in the off position a reference voltage is developed at the junction of resistors 152 and 154 by means of the switched ignition voltage 32 through the switch contacts 156a and 156c. The reference voltage is provided through contacts 150a and 150c of switch 150 charging the capacitor 86 to the reference voltage which is greater than the threshold voltage of the timer stage 80. When the switching arrangement 50 is moved to the on position, the capacitor 86 is connected to the junction of resistors 88 and 90 through the switch contacts 150b and 150a of switch 150. The voltage at the threshold input of the timer 80 is exceeded and the timer stage 80 is switched to the low output state at 82 rendering transistor 84 conductive. The transistor 84 provides an actuation signal to the wiper drive control stage 14 and thus an "instant-on" or immediate wiper cycle is accomplished as the switching arrangement 50 is operated.
The value of resistors 152 and 154 are chosen to result in a charge condition of capacitor 86 sufficient to exceed the threshold switching requirements of the timer stage 80 and in a specific embodiment a resistance of 4.7 Kohms for resistor 152 and a value of 15 Kohms for resistor 154 have been found suitable to practice the present invention and thereby provide a voltage sufficiently greater than the threshold voltage of the timer stage 80.
After the switching arrangement 50 is switched to the on state and the output 82 of the timer 80 is immediately switched to a low state, the capacitor 86 is subsequently discharged, Successive timing cycles or intervals are generated with predetermined variable delays being provided between successive wiper cycles according to the setting of the potentiometer delay control 74.
While there has been illustrated and described several embodiments of the present invention, it will be apparent that various changes and modifications thereof will occur to those skilled in the art. It is intended in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the present invention. | A variable delay windshield wiper control system is provided in conjunction with a conventional windshield wiper system of an automobile to control the operation wiper drive source and wiper drive mechanism at predetermined variable intervals. The variable delay wiper control system operates independently of the conventional wiper switch and is effective to provide an adjustable delay interval between successive windshield wiper sweeps or reciprocative paths as is desirable during light rain or precipitation conditions.
The wiper control system includes a timing circuit which generates variable duration intervals and directly effects operation of the drive source at the end of each of the intervals, and a delay control adjusted by the operator. A control switch is also provided for disabling the variable delay wiper control system and for effecting operation of the timing circuit. The control switch is also effective to directly control operation of the conventional drive source in one arrangement whereby an immediate windshield wiper sweep referred to as an "instant-on" condition is effected when the windshield wiper control system switch is moved from the off to the on position.
Another arrangement of the variable delay windshield wiper control system utilizes a control switch that initializes the timing circuit to provide an "instant-on" or immediate first wiper sweep upon actuation of the control switch so that a windshield wiper sweep clears the windshield immediately upon the actuation of the control system as opposed to waiting for the end of the first delay interval. | 8 |
BACKGROUND OF THE INVENTION
In, for example, a slab reheating furnace, it is known to make provision for heating the slabs from above and from below by supporting them above the furnace floor upon an open platform constituted by transversely spaced longitudinally extending skids. The skids are supported by columns, termed "verticals" through the intermediary of transversely extending members, termed "crossovers". The skids, verticals and crossovers may each be in the form of a central steel support pipe through which water flows as a coolant, and which is encased in a cladding of refractory material. In the case of a skid, a continuous segmented rider bar is set into the refractory cladding and makes contact with the slabs.
An object of the invention is to provide an improved structure which may be used in a furnace and which, with minor changes in design, may be used as a skid, vertical, crossover or the like.
Accordingly, the support pipe is clad with a number of prefabricated sections, each of which comprises a backing plate from which a number of metal anchor elements extend outwardly. The anchors are embedded in a refractory layer and may pass through an intermediate fibrous layer having low thermal conductivity which isolates the backing member and the root portions of the anchors from the heat of the furnace. The backing member may be formed from a steel plate or steel mesh and may be coextensive with the refractory material. Preferably, however, the backing member extends beyond the refractory material in the circumferential sense so as to provide one or more projecting tongues which may overlap a similar tongue or tongues of other similar prefabricated sections and be secured thereto and/or to the pipe.
DESCRIPTION OF DRAWINGS
FIG. 1 is a section through a unit suitable for use as a vertical or crossover; and
FIG. 2 is a cross-section through a unit suitable for use as a skid.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to the drawings, each of the units depicted is based upon a central support pipe 1 through which, when the furnace is in use, water flows as a coolant. In each case the pipe is enclosed by a composite jacket made up from a number of prefabricated sections, each consisting of a metal plate or mesh backing member 2, a refractory insulation 3, and an intermediate layer of material 4 having a very low thermal conductivity. The thermal conductivity of the layer 4 may be in the range of 0.5 to 1.5 and that of the insulation 3 about 10, BTU's per square foot per °F per hour per inch. The materials 3 and 4 are secured to the backing member 2 by means of anchors 5 which are welded to and project radially from the backing member so as to pass through the layer 4 and be embedded in the insulation 3.
The backing member is formed from any suitable metal, such as mild steel or heat resisting stainless steel.
During fabrication of either unit, the prefabricated sections are applied to the pipe and secured in place by a layer 7 of suitable cement. The joints between the sections are then sealed with an in-situ refractory insulation 8 after insertion of a layer of material 9 corresponding to, and forming an extension of, the material 4.
The two constructions depicted both have the features described above but differ in the following respects. In the case of the unit for use as a vertical or crossover, FIG. 1, the backing member of each section projects beyond the insulation to form tongues 10 which overlap, and may be secured to, similar tongues of the other section. In the embodiment shown in FIG. 2 which is intended for use as a skid, the presence of the rider bar 11 which bears directly upon, or may be integral with, the pipe renders this arrangement impracticable so that projecting tongues 12 terminate short of each other at the upper side of the unit. On the lower side, the sections are narrowly spaced from each other so that the backing member is here coextensive with the insulation.
By making use of the invention, several advantages are achieved compared with the known constructions. Firstly the layer 4 which may be in the form of a slab or fibrous blanket, may be employed to reduce heat losses, secondly, the anchors which reinforce the insulation are located in the zone wherein the minimum temperature prevails, and thirdly, the prefabricated sections can be secured to the pipe by means other than welding. | A structure which may be in the form of a furnace skid comprises a metal pipe encased with prefabricated sections each consisting of a backing member anchored to a refractory layer with an insulating layer in between. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a thermal processing jig for thermally processing a workpiece placed on a top surface thereof. More particularly, this invention is used as a jig for connecting plural members by brazing or the like, in which the plural members are connected by disposing brazing material at connecting portions between the plural members serving as a workpiece; then by mounting the workpiece applied with the brazing material on a top surface of the jig, then by placing the workpiece into a high temperature furnace, and then by melting the brazing material. This invention is also used as a jig for thermally processing plural workpieces coated with surface treatment material, e.g., thermosetting coating, in which the workpieces are thermally processed by mounting the workpieces on a top surface of the jig, and then by disposing the workpieces for a prescribed period into a high temperature furnace for heating the workpieces to a prescribed temperature.
2. Description of Related Art
In a conventional thermal processing jig, for example, a jig 20 shown in FIG. 4 including an outer peripheral frame 21 for structuring the jig 20 , a mounting portion 22 for mounting a workpiece thereon, and a stay 24 is formed rigidly by employing thick members and by fixedly connecting the members with welds 23 . In a case where the jig 20 having a workpiece mounted thereon is placed into a furnace, high-temperature heat causes thermal stress upon the jig 20 , and often results in deformation of the jig 20 . Therefore, in order to prevent deformation of the thermal processing jig, thick members are used for forming the jig rigidly.
Since the members of the rigidly formed jig are heated up from a cold state in a frequent and repetitive manner, then exposed to a high temperature atmosphere of 1100° C. or more inside a furnace, and then cooled to a cold state, the members are subject to considerable deformation caused by welding stress in a manufacturing process and internal stress from the property of the material due to heat difference between the heating process and the cooling process. In association with the deformation of the members, the workpiece mounted on the top surface of the mounting portion will also deform. Accordingly, a subsequent process of inspecting all products and an additional process of relieving the stress are necessary for products requiring accurate dimensional tolerance.
Forming the thick and rigid jig causes the jig to become heavy. Therefore, the weight of the jig itself will take up a large portion of the entire weight in processing with the furnace. That is, absorption of thermal energy by the jig has no significance from an aspect of heating energy. Most preferably, heating energy should only be applied upon the workpiece disposed inside the furnace. However, in reality, a considerable amount of heat is absorbed by the conventional rigid jig in a case where the jig and the workpiece are placed in a same atmosphere of high temperature. Therefore, a large space for a heating zone of the furnace and a long time for the heating process are required for the conventional jig. At the same time, since the jig has large thermal capacity, the jig is difficult to cool into a cold state. Therefore, a large space for a cooling zone when using a continuous thermal processing furnace and a long time for a cooling process are required for the jig. Repetitively using the jig for a numerous amount of times causes considerable thermal stress and results to considerable deformation, even to the rigidly formed jig. The thermally deformed jigs were disposed of since the jigs were difficult to be reused. Not only is the jig used for a short period, but is also unable to use thermal energy efficiently due to the large amount of heat absorption of the jig. Therefore, a large sized furnace and high running cost was necessary for the conventional jig.
It is an object this invention to solve the foregoing problems by providing a jig causing no or hardly any deformation from thermal stress upon the jig in a case where the jig is disposed into a thermal furnace along with a workpiece, thereby allowing the jig to be used for a period considerably longer than the conventional jig. By forming a thin and light-weight jig, the productivity for the operator can be increased, the amount of heat absorption of the jig placed inside a furnace can be reduced to enable a more efficient thermal processing of a workpiece, and the apparatus for thermal processing can be size-reduced to enable reduction in initial cost and running cost.
SUMMARY OF THE INVENTION
This invention provides a thermal processing jig for a workpiece including: an outer peripheral frame formed of a plurality of members; and a mounting portion arranged within the outer peripheral frame for mounting the workpiece, wherein the outer peripheral frame and the mounting portion are movably connected, wherein the plurality of members forming the outer peripheral frame are connected via an expansion space capable of absorbing expansion caused during thermal expansion of the outer peripheral frame and the mounting portion, and wherein the plurality of members forming the outer peripheral frame and a member constituting the mounting portion are connected via the expansion space.
This invention can also provide a thermal processing jig for a workpiece, wherein the outer peripheral frame and the mounting portion are movably connected by piercingly forming an insertion aperture at a connecting portion between the outer peripheral frame and the mounting portion, and by inserting the connection axis through the insertion aperture, for enabling each member of the outer peripheral frame and the mounting portion to move at the connection portion during thermal expansion of the outer peripheral frame and the mounting portion, wherein the insertion aperture is formed for inserting the connection axis therethrough, and wherein the connection axis has a diameter smaller than the insertion aperture.
This invention can also provide a thermal processing jig for a workpiece, wherein the plurality of members forming the outer peripheral frame are directly connected to each other, and wherein the plurality of members forming the outer peripheral frame and the mounting portion are directly connected.
This invention can also provide a thermal processing jig for a workpiece, wherein the plurality of members forming the outer peripheral frame are connected to each other via an intermediary attachment member, and wherein the plurality of members forming the outer peripheral frame and the mounting portion are connected via the intermediary member.
This invention can also provide a thermal processing jig for a workpiece, wherein the connection axis is removably connected to the insertion aperture.
This invention can also provide a thermal processing jig for a workpiece, wherein the connection axis is unremovably connected to the insertion aperture.
This invention can also provide a thermal processing jig for a workpiece, wherein the mounting portion is formed with a plurality of members.
This invention can also provide a thermal processing jig for a workpiece, wherein the mounting portion is formed from a single connected member or a single united bodied member.
With this invention, a workpiece targeted for thermal processing is mounted on a top surface of a mounting portion of a jig, and the jig having the workpiece mounted thereon is disposed into a thermal furnace. The workpiece is heated inside the thermal furnace and thermally processed, e.g., brazed, while the thermal energy is inevitably absorbed by the jig. The heating cause thermal expansion upon the members forming the jig. Despite the thermal expansion caused upon the members, each member is movably connected; furthermore, expansion spaces for absorbing the expansion of the members are formed between the members of the outer peripheral frame and also between the outer peripheral frame and the mounting portion.
The expansion spaces formed between the members therefore absorbs the expansion from the thermally expanded members, as opposed to a conventional example where members of a jig such as an outer peripheral frame and a mounting portion for mounting a workpiece are firmly connected by welding or the like. Each member, along with the expansion absorption of the expansion spaces, can absorb the stress created in association with the thermal expansion since each member is movably connected. Accordingly, the expansion spaces can therefore absorb the expansion, from the thermally expanded members, as opposed to a conventional example where members of a jig such as an outer peripheral frame and a mounting portion for mounting a workpiece are firmly connected by welding or the like.
Stress and deformation upon the jig as well as deformation of the workpiece from the stress of the jig can be prevented since the members are able to absorb the thermal expansion. Since deformation and thermal stress upon the jig can be prevented, the jig is not required to be formed rigidly, but is instead able to be formed only with strength sufficient for handling or mounting the workpiece. Accordingly, the members of the jig can be formed with a thin thickness, so that the thermal energy absorbed by the jig can be absorbed to an amount considerably less than that of the conventional jig. Accordingly, unnecessary absorption of thermal energy can be prevented and thermal processing of the workpiece can be provided efficiently. Consequently, the space for a heating zone inside a furnace and the time for heating can be reduced. At the same time, the jig having little thermal capacity is easy to cool into a cold state, thereby requiring less space for a cooling zone than the conventional jig in a case where a continuous thermal processing furnace is used and also requiring less time for a cooling process.
Each member is movably connected via an expansion space. In movably connecting the members, an insertion aperture is piercingly formed at a connecting portion of each member for inserting therethrough a connection axis, in which the connection axis having a smaller diameter than the insertion aperture is pierced therethrough. Forming the connection axis with a smaller diameter than the insertion aperture allows a play portion to be created in the insertion aperture. The play portion enables the members to move in association with the thermal expansion of the members.
Although the members of the jig include plural members forming the outer peripheral frame and the mounting portion arranged inside the outer peripheral frame for mounting the workpiece, the members can be directly connected via the insertion aperture and the connection axis, or connected via an intermediary attachment member. By connecting the members via the intermediary attachment member, the forming of the members of the jig can be simplified, thereby providing productivity and versatility for the jig.
In connecting the members directly, the members of the jig will be subject to a process such as bending. Therefore, direct connection of the members has a drawback of requiring more labor in processing the members of the jig. Nevertheless, direct connection of the members can simplify manufacture of the jig since no intermediary attachment member is required. Therefore, connection of the members can be determined according to the purpose for processing the workpiece. By forming the connection axis in a removable manner with respect to the insertion aperture, the connection axis can be removed from the members for allowing the members to be modified by pressing or the like. For example, a jig deformed into a wound state can be flattened and reused as a thermal processing jig. As opposed to the conventional jig, the jig of this invention will rarely be required to be discarded.
A considerable amount of thermal expansion can be absorbed even for a large sized mounting portion and thermal stress can be prevented by forming the mounting portion with plural members connected movably via the expansion space.
In a case where the jig is of a small size area, the mounting portion can also be formed from a single connected or united bodied member since the amount of thermal expansion is small and the expansion space formed between the mounting portion and the outer peripheral frame will be able to absorb the thermal expansion, thereby forming the jig with a simple structure and enabling manufacture of an inexpensive product.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and features of the invention are apparent to those skilled in the art from the following preferred embodiments thereof when considered in conjunction with the accompanied drawings, in which:
FIG. 1 is a perspective view showing a first embodiment;
FIG. 2 is an enlarged cross-sectional view showing a connecting relation between an insertion aperture and a connection axis;
FIG. 3 is an enlarged cross-sectional view showing a state where mounting portion is directly connected to an outer peripheral frame; and
FIG. 4 is a plan view showing a conventional example.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment of this invention will hereinafter be described with reference to the drawings. Numeral 1 is a jig for thermal processing having an outer peripheral frame 2 formed of plural members and a mounting portion 3 formed of plural members arranged inside the outer peripheral frame 2 . A top surface of the mounting portion 3 is formed for mounting thereon a workpiece 4 targeted for thermal processing and is processed suitably according to the workpiece 4 . The processing differs according to the object targeted as the workpiece 4 for thermal processing. For example, the top surface of the mounting portion 3 can be formed with irregularities, or with projecting support columns (not shown) for mounting and maintaining the workpiece 4 . The workpiece 4 for thermal processing can be of various kinds. For example, a workpiece 4 having brazing material disposed in between connecting portions of plural members of the jig 1 for connecting the plural members, a workpiece 4 for annealing or the like, a workpiece 4 for surface drying, or a workpiece for other thermal processing of preference.
The jig 1 for thermal processing comprises the outer peripheral frame 2 having a square shape or a rectangular shape. The outer peripheral frame 2 is comprised not of a single member but of a plurality of members. In an inner space of the outer peripheral frame 2 , the mounting portions 3 for mounting the workpiece 4 on the top surface thereof are disposed with a prescribed space therebetween. The mounting portion 3 is formed with a shape in accordance with the purpose for mounting the workpiece 4 targeted for thermal processing.
The plural members comprising the outer peripheral frame 2 and the mounting portion 3 are connected via an expansion space 5 capable of absorbing the expansion of the members during thermal expansion. The expansion space 5 should preferably be formed with a space of 1 mm to {fraction (1/100)} mm. An expansion space 5 over 1 mm causes shakiness of the jig 1 , decline of precision, and unstableness when the workpiece 4 is mounted. An expansion space 5 below {fraction (1/100)} mm cannot absorb the thermal expansion and contraction of the members due to mutual interference, thereby causing deformation. Various methods can be employed for forming the expansion space of 1 mm to {fraction (1/100)} mm between the members, such as by connecting each of the members via a spacer 9 having a thickness equal to a prescribed space of the expansion space 5 , and then by removing the spacer 9 after the connection.
Insertion apertures 6 are formed in the connecting portion between the plural members of the outer peripheral frame 2 and the plural members of the mounting portion 3 . The insertion aperture 6 has a connecting axis 7 formed therethrough for connection between the outer peripheral frame 2 and the mounting portion 3 , between the outer peripheral frame 2 and the outer peripheral frame 2 , or between the mounting portion 3 and the mounting portion 3 .
In one embodiment, the insertion aperture 6 is formed with a size of 3.3 mm, and the connecting axis 7 inserted through the insertion aperture 6 is formed with a 3.2 mm diameter. The connecting axis 7 is formed as a rivet having engagement heads on both ends thereof, wherein the diameter difference between the insertion aperture 6 and the connecting axis 7 is 0.1 mm. A large difference in diameter causes problems such as shakiness of the members comprising the jig 1 , or deformation of the workpiece 4 when the workpiece 4 is mounted. A small difference in diameter between the diameter of the insertion aperture 6 and the connection axis 7 causes disability in adjusting to the movement from the expansion of the members.
Accordingly, the diameter difference between the insertion aperture 6 and the diameter of the connecting axis 7 in one embodiment should preferably be ranged between approximately 0.2 mm to {fraction (1/100)} mm. Such diameter difference, together with the expansion space 5 , serves to absorb the expansion of the members during thermal expansion. Problems such as shakiness of the jig 1 in an unheated state can be restrained to a minimal degree, the workpiece 4 can be mounted on the top surface with more precision, and unstableness of the mounted workpiece 4 can be eliminated. Each of the members can be connected by using an intermediary attachment member 8 of an L-shaped angle or a rectangular pipe as shown in FIG. 2 . For example, in using the intermediary attachment member 8 of an L-shaped angle as shown in FIG. 2, the intermediary attachment member 8 of an L-shaped angle can be arranged in a corner portion of the outer peripheral frame 2 of the jig 1 . The insertion aperture 6 is piercingly formed in the intermediary attachment member 8 and the outer peripheral frame 2 , and the connecting axis 7 formed as a rivet is inserted through the piercingly formed insertion aperture 6 , thereby enabling connection in the corner portion of the outer peripheral frame 2 via the intermediary attachment member 8 .
Needless saying, each of the members connected by the connection axis 7 have the expansion space 5 of approximately 1 mm to {fraction (1/100)} mm disposed therebetween. In forming the expansion space 5 as shown in FIG. 2, the spacer 9 having a thickness of approximately 1 mm to {fraction (1/100)} mm is inserted between the members, and the members are then connected by the connection axis 7 . The spacer 9 is removed after the members are connected by the connection axis 7 , thereby forming the expansion space 5 and completing the connection of the members.
As shown in the bottom portion of FIG. 2, an intermediary attachment member 8 of a rectangular pipe is used. Although the insertion aperture 6 and the connection axis 7 are also formed in such a case, the intermediary attachment member 8 of a rectangular pipe is convenient for mounting the workpiece 4 on the mounting portion 3 inside the outer peripheral frame 2 . Spaces of approximately 1 mm to {fraction (1/100)} mm are formed between the intermediary attachment member 8 and the mounting portion 3 and also between the intermediary attachment member 8 and the outer peripheral frame 2 for enabling absorption of deformation caused by the thermal expansion of the intermediary attachment member 8 , or the members of the outer peripheral frame 2 , the mounting portion 3 , etc. A stainless plane material, for example, can be used for forming the intermediary attachment member 8 , the outer peripheral frame 2 , the mounting portion 3 or the like, in which the plane thickness in this embodiment is 2 mm.
Although the intermediary attachment member 8 is used for connecting the outer peripheral frame 2 and the mounting portion 3 in the foregoing embodiment, the outer peripheral frame 2 and the mounting portion 3 can be connected directly without use of the intermediary attachment member 8 as in this embodiment shown in the bottom portion of FIG. 3 . In such a case, an L-shaped bent portion 10 is formed at an end portion of the mounting portion 3 , and the insertion aperture 6 is formed in the mounting portion 3 , thereby allowing the connection axis 7 to be inserted through the insertion aperture 6 . Although this embodiment has an advantage of requiring no intermediary attachment member 8 , the L-shaped bent portion 10 is required to be formed for opening the insertion aperture 6 in the end portion of the mounting portion 3 , thereby requiring additional labor in forming the members. Nevertheless, the weight of the jig 1 can be lightened, the thermal capacity and the thermal energy of the jig 1 can be reduced, and the jig 1 can be cooled faster by not requiring the intermediary attachment member 8 .
Although the thickness for the outer peripheral frame 2 and the mounting portion 3 is 2 mm in the foregoing embodiment, the thickness is not to be restricted to 2 mm. The thickness can also be approximately 1 mm or 0.5 mm. The thickness can be determined according to the weight of the workpiece 4 targeted for mounting on the top surface, or the purpose of mounting the workpiece 4 . The thickness can be formed to a degree capable of preventing deformation of the jig 1 when held or transported in an ordinary procedure performed by an operator handling the workpiece 4 . An ideal jig 1 is one resistant to deformation from external force and thus formed with a thin thickness without adversely affecting the mounting of the workpiece 4 . Forming a thin jig 1 not only allows the jig 1 to be lightened and transported easily, but also reduces the absorption amount of thermal energy of the jig 1 when placed into a high temperature furnace. Since the thermal energy unabsorbed by the jig 1 can be added to the workpiece 4 , the jig 1 placed in the furnace 1 can be moved faster for enabling the workpiece 4 to be thermally processed efficiently. Forming the jig 1 with a thin thickness, however, causes the jig 1 to have a sharp property. Therefore, it is required to keep in mind that the sharp property of the jig 1 may, for example, cut the operator in a case where the jig 1 is hand-held.
Although the connection axis 7 is formed with use of a rivet in the foregoing embodiments, the connection axis 7 can also be formed with, for example, a bolt and a nut. Productivity may slightly be lower when using a bolt and a nut instead of using a rivet. The connection axis 7 can be formed firmly and can also be formed in an unremovable state with respect to the insertion aperture 6 .
Thus structured, thermal energy can be applied to the workpiece 4 and the jig 1 by mounting the workpiece 4 targeted for thermal processing on the top surface of the jig 1 and then by placing the jig 1 into a high temperature furnace. The thermal processing is performed according to the purpose of the workpiece 4 . Although the heat from thermal processing causes thermal expansion in each member of the jig 1 , the thermal expansion is absorbed by the expansion space 5 . The movement of the members during the absorption of thermal expansion by the expansion space 5 will be no problem since each member is connected movably.
In connecting the members via the connection axis 7 and the insertion aperture 6 , a gap of a certain extent is formed between the connection axis 7 and the insertion aperture 6 since the connection axis 7 inserted into the insertion aperture 6 has a smaller diameter than that of the insertion aperture 6 . Accordingly, each of the members of the jig 1 can expand within the extent of the gap, respectively. Therefore, the thermal expansion can be absorbed by each member of the jig 1 , and problems such as bending or deforming can be prevented. Since problems such as bending and deforming can be prevented, the jig 1 can be formed with no requirement of a rigid body structure for preventing deformation and can also be formed with a thin thickness for absorbing less thermal energy than the conventional product. More thermal energy can be applied to the workpiece 4 per unit of time, thereby the workpiece 4 inside the furnace can be moved at a higher speed for enabling quick thermal processing of the workpiece 4 .
In a case where the connection axis 7 is formed in a removable manner, the members of the jig 1 can be disassembled, restored into original form by pressing or the like, and reassembled for further use. Therefore, the members of the jig 1 can be economically restored and repaired even when slight deformation or the like is caused upon the workpiece 4 by long term use or by external impact or the like during handling of the workpiece 4 . Forming the connection axis 7 in a removable manner with respect to the insertion aperture 6 is not to be restricted to a typical method such as using a bolt and a nut. A rivet or the like can also be employed for connection as long as disassembly is possible.
Although the mounting portion 3 is formed from plural members in the foregoing embodiments, the mounting portion 3 , in a case where the jig 1 has a size of a small area, can also be formed from a single connected or united bodied member since the amount of thermal expansion is small and the expansion space 5 formed between the mounting portion 3 and the outer peripheral frame 2 can absorb the thermal expansion. Accordingly, the mounting portion 3 for a small sized jig 1 can be formed with a single member, thereby allowing the jig 1 to have a simple structure and enabling manufacture of an inexpensive product.
Thus structured, no or hardly any deformation is caused from thermal stress of the jig with this invention, thereby allowing the jig to be used for a long period. Since the workpiece mounted on the jig will not be subject to deformation in association with the thermal stress of the jig, procedures such as modifying the workpiece after the thermal processing of the workpiece will not be required, thereby enabling economical and precise thermal processing of the workpiece. | A jig for heat treatment of a workpiece capable of use over a long period of time by minimizing or eliminating deformation thereof caused by thermal distortion and which is capable of performing heat treatment of the workpiece by reducing the amount of heat energy absorbed by the jig in a heat-treatment furnace. The jig includes an outer peripheral frame formed by a plurality of members and a mounting portion arranged inside the outer peripheral frame and also formed by a plurality of members. The workpiece rests on the mounting portion during use. The members of the outer peripheral frame and mounting portion are movably connected to each other with an expansion space being provided between each adjacent member capable of absorbing thermal expansion of the member during thermal treatment. | 5 |
BACKGROUND
1. Field of Invention
The invention is directed to downhole cutting tools utilized in oil and gas wells to cut objects within the well and, in particular, to downhole blade mills that are used to cut away, among other objects, stuck tools, bridge plugs, well tubing, well casing, and the like disposed within the well.
2. Description of Art
In the drilling, completion, and workover of oil and gas wells, it is common to perform work downhole in the wellbore with a tool that has some sort of cutting profile interfacing with a downhole structure. Examples would be milling a downhole metal object with a milling tool, performing a washover operation with a rotary shoe, or cutting through a tubular with a cutting or milling tool. During the performance of these operations, it is common for the tool and/or drill string to which the tool is connected, to vibrate or bounce off of the object disposed within the wellbore that is being cut or abraded, causing inefficiencies in the cutting operations.
SUMMARY OF INVENTION
Broadly, the invention is directed to downhole cutting tools utilized in cutting (also referred to as abrading or milling) an object disposed within the well. The term “object” encompasses any physical structure that may be disposed within a well, for example, another tool that is stuck within the well, a bridge plug, the well tubing, the well casing, or the like. The downhole cutting tools disclosed herein include cutting elements disposed on a body. The cutting elements can be disposed on an outer wall surface of the body, or on blades disposed along the outer wall surface of the tool. The cutting elements are disposed on the body such that rotation of the body causes rotation of the cutting elements.
In one particular embodiment, the downhole cutting tool comprises a guide member disposed at an end of the tool. The guide member facilitates engagement of the tool with an object disposed in a wellbore. By engaging the guide member with the object, the tool rotation will follow a more circular path, thereby reducing the magnitude of lateral motion during cutting operations.
In other specific embodiments, the downhole cutting tools comprise cutting elements arranged in a staggered pattern. The cutting elements can be disposed directly on an outer wall surface of the body of the tool, or on one or more blades attached to the body of the tool.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a side view of one specific embodiment of a downhole cutting tool disclosed herein.
FIG. 2 is an enlarged view of the cutting elements shown on the embodiment illustrated in FIG. 1 .
FIG. 3 is a side view of another specific embodiment of a downhole cutting tool disclosed herein.
FIG. 4 is a partial cross-sectional view of an object disposed in a wellbore showing the downhole tool of FIG. 1 being lowered to engage the object.
FIG. 5 is a partial cross-sectional view of the object disposed in the wellbore shown in FIG. 4 showing the downhole tool of FIG. 1 engaged with the object prior to rotation of the tool and, thus, cutting of the object.
While the invention will be described in connection with the preferred embodiments, it will be understood that it is not intended to limit the invention to these embodiments. On the contrary, it is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF INVENTION
Referring now to FIGS. 1-3 , downhole cutting tool 20 comprises body 21 having first or upper end 22 , second or lower end 23 , and longitudinal axis 24 . First or upper end 22 is adapted to be connected to a drill or work string 80 ( FIGS. 4-5 ), such as through a threaded connection shown in FIGS. 1 and 3 . Cutting elements 40 are disposed along outer wall surface 26 of body 21 . In the embodiments of FIGS. 1-3 , cutting elements 40 are disposed on a plurality of blades 30 . It is to be understood, however, that blades 30 are not required. Instead, cutting elements 40 can be disposed directly on outer wall surface 26 or on any other structure desired or necessary to facilitate cutting of an object disposed in a wellbore.
In the embodiments shown in the FIGS. 1-5 , tool 20 is a blade mill having a plurality of blades 30 . One or more of blades 30 can be a “stepped blade” having a stepped profile along cutting end 31 such as shown in FIGS. 1 and 3 . As shown in FIGS. 1 and 3 , the profile along cutting end 31 includes first, second, and third steps 32 , 33 , 34 . Thus, in the embodiments of FIGS. 1-5 , tool 20 is a “stepped blade mill.”
Although the cutting elements 40 can be disposed on cutting faces 36 in numerous arrangements, in the embodiments of FIGS. 1-5 , cutting elements 40 are disposed on cutting faces 36 of blades 30 in three columns. First column 41 is disposed parallel to, and closest to, longitudinal axis 24 . Second column 42 is disposed adjacent first column 41 and parallel to longitudinal axis 24 . Third column 43 is disposed adjacent second column 42 and parallel to longitudinal axis 24 . Third column 43 of cutting elements 40 is the furthest from longitudinal axis 24 and closest to the outer edge of cutting face 36 .
In addition to being disposed in columns, cutting elements 40 of first column are disposed in a staggered relationship relative to cutting elements 40 of second column. Similarly, cutting elements of second column 42 are disposed in a staggered relationship relative to cutting elements 40 of third column 43 . As best shown in FIG. 2 , in one particular embodiment, cutting elements 40 of first column 41 are offset relative to cutting elements 40 of second column 42 such that upper surfaces 61 of one or more of cutting elements 40 of first column 41 is not aligned with upper surface 63 or a lower surface 65 of an adjacent cutting element 40 of the second column 42 . In other words, upper surface 61 of one or more cutting elements 40 of first column 41 is level with a point disposed along height 67 between upper surface 63 and lower surface 65 of at least one cutting element 40 of second column 42 . The point can be disposed half-way between upper surface 63 and the lower surface 65 , i.e., the mid-point (as shown in FIGS. 1-3 ), or any other point in-between.
Additionally, as illustrated in FIGS. 1 and 3 , the lowermost cutting element 40 of each of first, second, and third columns 41 , 42 , 43 is disposed such that cutting elements 40 extend beyond (i.e., away from the cutting end 31 ) the stepped profile along cutting surface 31 that defines first, second, and third steps 32 , 33 , 34 . The arrangement of cutting elements 40 in this manner lessens exposure of blades 30 , and cutting surface 36 to the object so that cutting elements 40 can more efficiently cut the object disposed in the well.
Disposed at lower end 23 of body 21 is guide member 50 . Guide member 50 extends beyond lower end 23 for engagement with the object disposed in the wellbore. Guide member 50 includes a profile for engaging with the an engagement member disposed on the object to stabilize cutting tool 20 during cutting of the object. The profile of guide member 50 can include at least a partial spherical shape ( FIG. 1 ), or tool apex 55 ( FIG. 3 ) defined by one or more cutting elements 40 being disposed on lower end 23 . In embodiments in which cutting elements 40 define apex 55 , one or more of cutting elements 40 can be disposed at non-right angles relative to lower end 23 as shown in FIG. 3 . In addition, in embodiments in which at least two cutting elements 40 define apex 55 , at least two of the cutting elements 40 can be disposed facing each other. Inclusion of cutting elements 40 as guide member 50 allows guide member 50 to cut or abrade the object in addition to providing stability to the downhole tool 20 during operation. In other words, during rotation of the work string containing downhole tool 20 , cutting elements 40 of guide member 50 cut an opening in the object into which guide member 50 is inserted so as to stabilize downhole tool 20 during further cutting of the object. Thus, guide member 50 having one or more cutting elements 40 cuts an opening large enough such that guide member can enter and engage the interior surface of the object to provide stabilization.
Referring now to FIGS. 4-5 , downhole cutting tool 20 is secured to drill string 80 and disposed within wellbore 84 . Disposed within wellbore 84 is object 90 having engagement member 91 defining engagement member interior surface 92 . The profile of guide member 50 of tool 20 is shaped to be received by engagement member 91 . As used herein, “received” is understood to have its broadest meaning requiring only that guide member 50 is able to engage with engagement member 91 . It is to be understood that the engagement between guide member 50 and engagement member 91 is not required to have a low tolerance fit. All that is required is that guide member 50 can engage with engagement member 91 such that tool 20 and, thus, drill string 80 , are stabilized during cutting operations thereby preventing tool 20 or string 80 to experience vibration or bounce causing a decrease in the efficiency of the cutting as compared to a tool lacking guide member 50 . In one particular embodiment, engagement member 91 comprises a bore that extends the entire longitudinal length of object 90 . In other embodiments, engagement member 91 comprises a recess reciprocally-shaped to the shape or profile of guide member 50 . For example, engagement member 91 can be a concave-shaped recess to receive spherical-shaped guide member 50 ( FIG. 1 ).
In operation, drill string 80 is lowered within wellbore 84 ( FIG. 2 ) until guide member 50 engages with engagement member 91 of object 90 ( FIG. 5 ). Drill string 80 is rotated causing cutting elements 40 to cut or abrade away object 90 . Due to the outer diameter of drill string 80 being smaller than the inner diameter of wellbore 84 , drill string 80 is prone to vibrate or bounce upward off of object 90 . To lessen the likelihood of this happening, the engagement of guide member 50 with engagement member 91 stabilizes tool 20 and, thus, drill string 80 . Drill string 80 continues to rotate and move downward as object 90 is cut or abraded away. The rotation and cutting continues until object 90 is removed from wellbore 84 . Thereafter, drill string 80 is removed from wellbore 84 so that other downhole operations can be performed within wellbore 84 .
It is to be understood that the invention is not limited to the exact details of construction, operation, exact materials, or embodiments shown and described, as modifications and equivalents will be apparent to one skilled in the art. For example, the materials forming the components, the dimensions of each of the components, and the arrangement of the cutting elements can be modified as desired or necessary effectuate the best device for cutting an object disposed in a well. In addition, the guide member is not required to be spherically-shaped or be composed of angled cutting elements. Other guide members and their equivalents can be included as part of certain of the embodiments disclosed herein. Moreover, the cutting elements are not required to have the shapes and dimensions disclosed herein. Additionally, although the upper surfaces and lower surfaces of the cutting elements of the first and second columns are discussed with respect to specific reference numerals, it is to be understood that all of the cutting elements include an upper surface, a lower surface, and a height in the same manner as those discussed with respect to the cutting elements of the first and second columns. Further, it is to be understood that the term “wellbore” as used herein includes open-hole, cased, or any other type of wellbores. In addition, the use of the term “well” is to be understood to have the same meaning as “wellbore.” Moreover, in all of the embodiments discussed herein, upward, toward the surface of the well ( FIGS. 4-5 ), is toward the top of Figures, and downward or downhole (the direction going away from the surface of the well) is toward the bottom of the Figures. However, it is to be understood that the tools may have their positions rotated in either direction any number of degrees. Accordingly, the tools can be used in any number of orientations easily determinable and adaptable to persons of ordinary skill in the art. In addition, referring to a component as being “upper” or “lower” does not dictate the orientation of the component when placed in a well. Accordingly, the invention is therefore to be limited only by the scope of the appended claims. | Downhole cutting tools such as blade mills comprise a body having an upper end for connection with a rotating component of a drill string and a guide member disposed at lower end. The guide member can comprise a shape that is reciprocal to an engagement member disposed on an object within the well that is to be cut by the cutting mill. In certain embodiments, the guide member comprises a portion that is spherically shaped or an apex formed by two angled cutting elements. The cutting tools can also include one or more blades having cutting elements disposed thereon in a stepped arrangement. In one such embodiment, the cutting elements are disposed to cover one or more steps profiled on a lower end of the blade to lessen wear of the blade caused by the cutting of the object by the blade. | 4 |
BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention relates to a yarn tension control device, especially to a yarn tension control device used on a knitting machine for controlling tension of different warp yarns and providing a constant tension over the warp yarns on the knitting machine. Thus a stable yarn tension over the warp yarns gives uniform fabric appearance.
Description of Related Art
[0002] Generally, yarns used on a warp beam of a knitting machine including rapier loom are textile yarns. After the textile yarns being passed through bars for drop wires, and drop wires and then entered steel healds and reeds, their tension is easily controlled within a certain range. During knitting of weft yarns, a constant tension over the warp yarns is required in the conventional textile technology.
[0003] Refer to Fig. 1 and FIG. 2 , a conventional rapier loom is revealed. Yarns on a warp beam 10 are textile yarns. After passed through a guide holder 91 , a back rest sensing roller 92 , bars for drop wires 93 , drop wires 94 and entered steel healds 95 , the tension of the yarns is easily controlled within a certain range. During weaving of weft yarns after passage of reeds 96 , a constant yarn tension over the warp yarns is ensured. After the weaving of the wefts on the warps, fabric formed by the textile yarns is drawn by a cloth roller 100 . In the conventional rapier loom, only common fabric can be drawn and produced because that a constant yarn tension over the yarns is required.
[0004] Once metal yarns and textile yarns with different tensions are fed into the conventional knitting machine (including the rapier loom) and wound around the warp beam, warping is getting difficult. Besides increasing difficulty in warping, the different tensions of the metal yarns and the textile yarns from the yarn disc to the knitting machine for being woven lead to unstable yarn tension over the warp yarns. Thus the appearance of the fabric produced is uneven.
[0005] Thus there is room for improvement and there is a need to provide a novel yarn tension control device that solves the problems mentioned above.
SUMMARY OF THE INVENTION
[0006] Therefore it is a primary object of the present invention to provide a yarn tension control device that is applied to knitting machines for providing a constant yarn tension over different warp yarns on the knitting machine. Thus uniform fabric appearance is given by a stable yarn tension over the warp yarns during weaving.
[0007] In order to achieve the above object, a yarn tension control device according to the present invention includes a main support, a yarn disc disposed on one side of the main support, a clamp support arranged at the other side of the main support, a rotary disc located in the clamp support, a rubber set disposed on the clamp support for control of rotational speed of the rotary disc, and a rotatable clamping roller connected to the main support. The knitting machine is arranged with a plurality of yarn tension control devices for control of metal yarns while weaving warp yarns to produce fabrics. The metal yarns on the yarn disc are passed through a guide holder, bars for drop wires, and drop wires and then entered steel healds and reeds. Thus a constant yarn tension over each warp yarn is ensured by the respective yarn tension control devices while knitting weft yarns. Therefore uniform fabric appearance is provided by a stable yarn tension over the warp yarns during the weaving process.
[0008] An adjustment switch is arranged at the clamp support. The adjustment switch consists of a rod that is passed through an opening of the clamp support, a spring fit around the rod, and a knob fastened on a rear end of the rod for adjustment of an opening distance of the clamp support.
[0009] The metal yarns or textile yarns are fixed on the yarn disc after warping so that the yarn tension control device is independent of the warp beam. The yarn tension control device is used to adjust and control a tension of the metal yarn or the textile yarn from the yarn disc. Thus a stable fabric take-off speed is reached according to the tension of the warp yarns on the warp beam, the running speed of the knitting machine and the fabric weft density so as to produce fabric with certain weft density. Therefore the appearance of the fabric produced is uniform.
[0010] The yarn tension control device can be applied to knitting machines while producing special fabrics including conductive heating fabric, electromagnetic shielding fabric, radar absorbent fabric, etc. for control of tension of metal yarns or textile yarns in warp yarns therein. A plurality of yarn tension control devices is used while producing fabric.
[0011] The yarns tension control device is used during weaving of fabric formed by textile yarns. A plurality of metal yarns is woven on edges of two sides of the fabric surface. The metal yarns can be conductive metal yarns or non-conductive metal yarns.
[0012] The yarns tension control device is used during weaving of fabric formed by textile yarns. The fabric produced by textile yarns includes a plurality of textile yarns woven on edges of two sides of the fabric surface used as scrap yarns during knitting.
[0013] The clamping roller is connected to one end of the connecting rod and a bearing is mounted in the clamping roller so as to make the clamping roller rotatable and able to press against the yarns on the yarn disc. The yarns can be metal yarns or textile yarns.
[0014] In order to achieve the above object, a yarn tension control device according to the present invention includes a main support, a yarn disc and a rotary disc that are disposed on one side of the main support, a support fixing member arranged at one side of the rotary disc, an adjusting rod set moveable in the support fixing member, a belt mounted around the rotary disc for control of rotational speed of the rotary disc, and a rotatable a clamping roller connected to the main support. A plurality of yarn tension control devices is used for control of warp yarns respectively while weaving the warp yarns to produce fabrics. The warp yarns can be metal yarns. The metal yarns on the yarn disc are passed through a guide holder, bars for drop wires, and drop wires and then entered steel healds and reeds. Thus a constant yarn tension over the warp yarns is ensured by the yarn tension control devices during a weaving process of weft yarns. The tension of the metal yarns is the same with the tension of the textile yarns. Thereby a stable yarn tension over the warp yarns gives uniform fabric appearance.
[0015] The adjusting rod set consists of an adjusting bolt and a locking nut. The adjusting bolt is passed through and moveable in a guide slot while the locking nut is fastened on the adjusting bolt and used for positioning the adjusting bolt in the guide slot.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein:
[0017] FIG. 1 is a partial schematic drawing of a conventional rapier loom with a cloth roller;
[0018] FIG. 2 is a partial schematic drawing of a conventional rapier loom with a warp beam;
[0019] FIG. 3 is a schematic drawing showing embodiments of the present invention being disposed on a rapier loom with a warp beam according to the present invention;
[0020] FIG. 4 is a schematic drawing showing embodiments of the present invention being disposed on a rapier loom with a cloth roller according to the present invention;
[0021] FIG. 5 is a perspective view of a plurality of embodiments disposed on a frame of a knitting machine according to the present invention;
[0022] FIG. 6 is a perspective view of an embodiment according to the present invention;
[0023] FIG. 7 is a perspective view of an embodiment viewed from another angle according to the present invention;
[0024] FIG. 8 is a front side view of an embodiment according to the present invention;
[0025] FIG. 9 is a left side view of an embodiment according to the present invention;
[0026] FIG. 10 is a right side view of an embodiment according to the present invention;
[0027] FIG. 11 is a schematic drawing showing a side view of a rapier loom disposed with embodiments according to the present invention;
[0028] FIG. 12 is a perspective view of another embodiment according to the present invention;
[0029] FIG. 13 is a perspective view of another embodiment viewed from another angle according to the present invention;
[0030] FIG. 14 is a perspective view of fabric produced by a knitting machine disposed with an embodiment according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0031] In order to learn technical content, purposes and functions of the present invention, please refer to the following embodiments, related figures and reference numbers.
[0032] Refer from FIG. 1 to FIG. 5 , a plurality of yarn tension control devices 2 according to the present invention is disposed over a knitting machine 1 while in use.
[0033] The yarn tension control device 2 includes a main support 21 set over the knitting machine 1 . A main shaft 211 is passed through the main support 21 and is arranged with a yarn disc 22 and a rotary disc 25 . The yarn disc 22 is wound with yarns. A rotatable clamping roller 27 is disposed on the main support 21 and is used for pressing against the yarns of the yarn disc 22 . The yarn disc 22 and the rotary 25 are rotated at the same speed along with the yarns being drawn by an external force. A friction damper B is set on one side of the rotary disc 25 correspondingly and is used to control and adjust rotational speed of the rotary disc 25 .
[0034] While in use, the friction damper B in the yarn tension control device 2 can adjust and control the rotational speed of the rotary disc by frictional resistance, tightness of the belt or arrangement of the electric brake system.
[0035] Refer to FIG. 5 , FIG. 6 , FIG. 7 and FIG. 8 , a yarn tension control device 2 according to the present invention is composed of a main support 21 , a yarn disc 22 , a clamp support 23 , a rotary disc 25 , a rubber set 26 and a rotatable clamping roller 27 .
[0036] The main support 21 is a base installed over the knitting machine 1 . A main shaft 211 and a connecting rod 212 are passed through and arranged at the main support 21 while a fixing base 213 is disposed on one end of the main shaft 211 .
[0037] The yarn disc 22 is fit on the fixing base 213 and is wound with yarns (including metal yarns 4 or textile yarns 5 ). The yarns are used for warp knitting.
[0038] The clamp support 23 is disposed on one end of the connecting rod 212 and an adjustment switch 24 is arranged at a rear end of an opening of the clamp support 23 .
[0039] The rotary disc 25 is connected to the other end of the main shaft 211 and located in the opening of the clamp support 23 .
[0040] The rubber set 26 is fixed in the opening of the clamp support 23 and located on the left side and the right side of the rotary disc 25 .
[0041] The rotatable clamping roller 27 is arranged at the other end of the connecting rod 212 and is used for pressing against the yarn around the yarn disc 22 .
[0042] Refer to FIG. 3 , FIG. 4 and FIG. 5 , a plurality of yarn tension control devices 2 is installed on a frame 11 of the knitting machine 1 (the conventional rapier loom shown in FIG. 3 and FIG. 4 ) while in use. The yarn 22 of the yarn disc 22 includes metal yarns 4 or textile yarns 5 . After being passed through a guide holder 6 , bars for drop wires 93 and drop wires 94 , the metal yarns 4 are entered steel healds 95 . At the same time, general textile yarns 5 on a warp beam 10 are also passed through a guide bar 91 , a back rest sensing roller 92 , the bars for drop wires 93 , the drop wires 94 and entered the steel healds 95 . Then the metal yarns 4 and textile yarns 5 are passed through different reeds 96 respectively. After being weaved with weft yarns 7 , blended fabric A formed by the metal yarns 4 and the textile yarns 5 is obtained.
[0043] Refer from FIG. 6 to FIG. 11 , a bearing 3 is mounted in the main support 21 of the yarn tension control device 2 . After the main shaft 211 being passed through the bearing 3 , one end of the main shaft 211 is set with the fixing base 213 and the yarn disc 22 while the other end of the main shaft 211 is arranged with the rotary disc 25 so as to form a linked rotating mechanism. Then the clamping roller 27 is connected to one end of the connecting rod 212 and another bearing 3 is mounted in the clamping roller 27 so as to form the rotatable clamping roller 27 that is pressed against the yarns on the yarn disc 22 (including the metal yarns 4 and the textile yarns 5 ).
[0044] The other end of the connecting rod 212 on the main support 21 is set with the clamp support 23 . The clamp support 23 is a C-shaped piece with an opening while the rotary disc 25 is located in the opening of the clamp support 23 and the rubber set 26 corresponding to the rotary disc 25 is disposed on the clamp support 23 . The rubber set 26 is fixed in the opening of the clamp support 23 and located on the left side and the right side of the rotary disc 25 . Then a rear end of an opening of the clamp support 23 is arranged with the adjustment switch 24 . As shown in FIG. 8 , the adjustment switch 24 consists of a rod 241 , a spring 242 and a knob 243 . The rod 241 is passed through the opening of the clamp support 23 and the spring 242 is set around the rod 241 while the knob 243 is fastened on a rear end of the rod 241 for adjustment of friction of the rubber set 26 with respect to the rotary disc 25 . The rotational speed of the rotary disc 25 is affected by the rubber set 26 . Thus the magnitude of the speed and the tension of the metal yarns 4 or the textile yarns 5 being drawn into the knitting machine 1 can be controlled.
[0045] The rubber set 26 has a two-piece structure. The tension of the yarns on the yarn disc 22 is increased when the knob 243 is turned for adjustment of the tension of the spring 242 and the two-piece rubber set 26 clips the rotary disc 25 more tightly. On the other hand, the tension of the yarns is reduced while the rotary disc 25 is clamped less tightly. Thus users can turn the knob 243 for adjustment of the yarn tension according to their requirements on production.
[0046] Moreover, besides the tightness of the rubber set 26 , the rotational speed of the rotary disc 25 can also be affected by other factors. Refer to FIG. 12 and FIG. 13 , another embodiment of the present invention is revealed. In this embodiment, a yarn tension control device 2 includes a main support 21 , a yarn disc 22 , a rotary disc 25 , a rubber set and a clamping roller 27 .
[0047] The main support 21 is a base installed over the knitting machine 1 and a main shaft 211 is passed therethrough.
[0048] The yarn disc 22 is fit on the main shaft 211 and is wound with yarns.
[0049] The rotary disc 25 is arranged at the main shaft 211 , and located on one side of the yarn disc 22 . A guide groove 251 is disposed around the circumference of the rotary disc 25 .
[0050] The rubber set is located on one side of the rotary disc 25 and having a support fixing member 28 and a belt 29 . The support fixing member 28 including a guide slot 281 is set on one end of the main support 21 while an adjusting rod set 30 is passed through the guide slot 281 and is moveable in the guide slot 281 . The belt 29 is mounted in the guide groove 251 and wound around the rotary disc 25 . One end of the belt 29 is a fixed end 290 while the other end thereof is disposed with a hook spring 291 being hooked to the adjusting rod set 30 . The friction of the belt 29 in relation to the rotary disc 25 can be adjusted by displacement of the adjusting rod set 30 .
[0051] The clamping roller 27 is rotatable and is arranged at the main support 21 for pressing against yarns around the yarn disc 22 .
[0052] Refer to FIG. 12 and FIG. 13 , this embodiment is disposed on a knitting machine in a similar way as the embodiment mentioned above. The difference between this embodiment and the above one is in that friction damping is from the belt in this embodiment. In both embodiments, the main support 21 is arranged with a bearing 3 therein. The main shaft 211 is disposed with the yarn disc 22 and the rotary disc 25 respectively after being passed through the main support 21 to form a linked rotating mechanism. Then another bearing 3 is mounted in the clamping roller 27 so that the clamping roller 27 is rotatable and able to press against the yarns on the yarn disc 22 . The yarns can be metal yarns 4 or textile yarns 5 .
[0053] Next the support fixing member 28 of the rubber set is fastened and fixed on the main support 21 . The adjusting rod set 30 is passed through the guide slot 281 of the support fixing member 28 . The adjusting rod set 30 consists of an adjusting bolt 301 and a locking nut 302 . The position of the adjusting bolt 301 in the guide slot 281 is fixed by the locking nut 302 after being inserted through the guide slot 281 and being adjusted properly. One end of the belt 29 is a fixed end 290 that is fixed on the main support 21 or is positioned at a rod which the clamping roller 27 is disposed on. Later the belt 29 is mounted in the guide groove 251 and wound around the rotary disc 25 . As to the hook spring 291 on the other end of the belt 29 , it is hooked onto the adjusting rod set 30 . Thus friction damping that works on the rotary disc 25 is generated by the belt 29 .
[0054] The further the adjusting bolt 301 is away from a fixed end on top of the guide slot 281 , the tighter and closer the belt 29 is clamped while the adjusting bolt 301 being adjusted and moved in the guide slot 281 . That means the larger the yarn tension of the yarns on the yarn disc 22 . On the other hand, the looser the belt 29 , the smaller the yarn tension is. Users can adjust the adjusting rod set 30 according to their own requirements on production.
[0055] Refer to FIG. 14 , the present yarn tension control device is suitable to be applied to fabric A made from the textile yarns 5 . The fabric edge on each of two sides of the fabric A is woven with a plurality of the metal yarns 4 that are metal yarns or non-conductive metal yarns. The fabric A produced can be conductive heating fabric, electromagnetic shielding fabric or radar absorbent fabric.
[0056] The present yarn tension control device 2 can also be used to weave the textile yarns 5 for control of tension of the textile yarns 5 being drawn. During knitting, a plurality of textile yarns 5 is weaved on edges of two sides of the fabric surface and used as scrap yarns. The textile yarns 5 can be pure yarns or blended yarns.
[0057] Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalent. | A yarn tension control device of knitting machines is revealed. A plurality of yarn tension control devices is disposed on a knitting machine for control of warp yarns while weaving the warp yarns to produce fabrics. The warp yarns can be metal yarns. The metal yarns on a yarn disc are passed through a guide holder, bars for drop wires, and drop wires and then entered steel healds and reeds. Thus a constant yarn tension over the warp yarns is ensured by the yarn tension control devices during a weaving process of weft yarns. The tension of the metal yarns is the same with the tension of textile yarns. Thereby a stable yarn tension over the warp yarns gives uniform fabric appearance. | 3 |
RELATED APPLICATIONS
[0001] This is a continuation of U.S. patent application Ser. No. 14/775,071 filed 11 Sep. 2015, now ______, which is a 35 USC 371 U.S. National Phase of International Application No. PCT/US2013/035616, filed 08 Apr. 2013 and published in English as WO 2014/168604A1 on 16 Oct. 2014. The contents of the aforementioned applications are incorporated by reference in their entirety.
FIELD OF THE INVENTION
[0002] This invention relates to a system and method to improve the energy-efficiency of conventional carbonaceous feedstock plug feeder systems. More particularly, the present invention concerns an arrangement which permits a synchronous process for the advancement, pressurization, and retraction of a plurality of co-acting piston cylinder assemblies which together may be used to apply necessary forces for the creation of one or more plugs of compressible material for feeding into a reactor.
BACKGROUND
[0003] FIG. 1 shows a prior art feeding apparatus ( 02 ). Prior art feeding apparatus ( 02 ) comprises the following main components a first piston cylinder assembly ( 04 ), a second piston cylinder assembly ( 06 ), a third piston cylinder assembly ( 08 ), a first cylinder ( 10 ), a second cylinder ( 12 ), and a final, third cylinder ( 14 ), together with a plug disintegrator assembly ( 18 ), and a reactor feed screw assembly ( 22 ) to deliver the plugs to a reactor ( 104 ).
[0004] The first piston cylinder assembly ( 04 ) is comprised of: a first hydraulic cylinder ( 24 ), a first hydraulic cylinder front cylinder space ( 26 ), a first hydraulic cylinder rear cylinder space ( 28 ), a first hydraulic cylinder front connection port ( 30 ), a first hydraulic cylinder rear connection port ( 32 ), a first piston rod ( 34 ), a first hydraulic cylinder piston ( 36 ), a first hydraulic cylinder flange ( 38 ), and a first piston ram ( 40 ).
[0005] The first piston ram ( 40 ) is partly accommodated and arranged to travel in a reciprocating manner inside the first cylinder ( 10 ) which has associated therewith a feedstock inlet ( 42 ), a first cylinder first flange ( 44 ), and a first cylinder second flange ( 46 ). The first hydraulic cylinder flange ( 38 ) is connected to the first cylinder first flange ( 44 ).
[0006] The second piston cylinder assembly ( 06 ) is comprised of: second hydraulic cylinder ( 48 ), a second hydraulic cylinder front cylinder space ( 50 ), a second hydraulic cylinder rear cylinder space ( 52 ), a second hydraulic cylinder front connection port ( 54 ), a second hydraulic cylinder rear connection port ( 56 ), a second piston rod ( 58 ), a second hydraulic cylinder piston ( 60 ), a second hydraulic cylinder flange ( 62 ), and a second piston ram ( 64 ).
[0007] The second piston ram ( 64 ) is partly accommodated and arranged to travel in a reciprocating manner inside the second cylinder ( 12 ) which has associated with it a second cylinder first flange ( 66 ), a second cylinder second flange ( 68 ), a second cylinder third flange ( 70 ), and a cylindrical second pipe branch opening ( 72 ). The second hydraulic cylinder flange ( 62 ) is connected to the second cylinder first flange ( 66 ).
[0008] The first cylinder second flange ( 46 ) is connected to the second cylinder third flange ( 70 ) so as to allow a carbonaceous feedstock to be transferred through the first cylinder ( 10 ) by the advancing motion of the first piston ram ( 40 ) and partially compressed into the second cylinder ( 12 ) through the cylindrical second pipe branch opening ( 72 ).
[0009] The third piston cylinder assembly ( 08 ) is comprised of: third hydraulic cylinder ( 74 ), a third hydraulic cylinder front cylinder space ( 76 ), a third hydraulic cylinder rear cylinder space ( 78 ), a third hydraulic cylinder front connection port ( 80 ), a third hydraulic cylinder rear connection port ( 82 ), a third piston rod ( 84 ), a third hydraulic cylinder piston ( 86 ), a third hydraulic cylinder flange ( 88 ), and a third piston ram ( 90 ).
[0010] The third piston ram ( 90 ) is partly accommodated and arranged to travel in a reciprocating manner inside the final, third cylinder ( 14 ) which has associated with it a third cylinder first flange ( 92 ), a third cylinder second flange ( 94 ), a third cylinder third flange ( 96 ), and a cylindrical third pipe branch opening ( 98 ). The third hydraulic cylinder flange ( 88 ) is connected to the third cylinder first flange ( 92 ).
[0011] The second cylinder second flange ( 68 ) is connected to the third cylinder third flange ( 96 ) so as to allow a carbonaceous feedstock to be transferred through the second cylinder ( 12 ) by the advancing motion of the second piston ram ( 64 ) and partially compressed into the final, third cylinder ( 14 ) through the cylindrical third pipe branch opening ( 98 ).
[0012] After loose carbonaceous feedstock is transferred to the final, third cylinder ( 14 ) from the advancing motion of the second piston ram ( 64 ), the feedstock is then advanced through the final, third cylinder ( 14 ) by the advancing motion of the third piston ram ( 90 ) where it is compressed to develop a plug ( 100 ) of defined length and pressure to form the seal between the pressurized thermochemical reactor ( 104 ) and the feedstock inlet ( 42 ), which may be exposed to the atmosphere.
[0013] As seen in FIG. 1 , the plug forms the primary seal between the pressurized thermochemical reactor ( 104 ) and the feedstock inlet ( 42 ). One of the three pistons is always in a closed position, which prevents a plug blow-out if the plug becomes unstable and provides additional safety against syngas leaks. Reference characters (L 1 ) and (L 2 ) indicate the stroke starting position (L 1 ) and maximum stroke length position (L 2 ), respectively, of terminal plug-forming end of the third piston ram ( 90 ). In a preferred configuration, the compressible material is pressed to form a plug with a pressure of 10-1000 bars by the advancing movement of the third piston ram ( 90 ).
[0014] As plugs are successively formed they are transferred to a plug disintegrator assembly ( 18 ) which breaks up the formed plug for transference into the fluidized bed ( 102 ) of the pressurized thermochemical reactor ( 104 ) via a reactor feed screw assembly ( 22 ).
[0015] U.S. Pat. No. 7,964,004 shows an assembly which includes three single-acting pistons for use in a system of the sort seen in FIG. 1 .
SUMMARY OF THE INVENTION
[0016] In one aspect, the present invention is directed to a hydraulic circuit comprising:
[0017] a controller;
[0018] a primary hydraulic fluid source;
[0019] a platen configured to selectively move along a forward compression direction ( 310 ) and a rearward non-compression direction;
[0020] first and second ancillary piston cylinder assemblies, having respective first and second pistons operatively connected to the platen;
[0021] a third main piston cylinder assembly having a third piston operatively connected to the platen; and
[0022] wherein:
[0023] in a first mode of operation, hydraulic fluid is introduced under pressure into the first and second ancillary piston cylinder assemblies, thereby causing the first and second pistons to urge the platen in the forward compression direction, while the third piston passively travels in the forward compression direction;
[0024] in a second mode of operation, hydraulic fluid is introduced under pressure into the first and second ancillary piston cylinder assemblies and also into the third main piston cylinder assembly, thereby causing the first, second and third pistons to collectively urge the platen in the forward compression direction; and
[0025] in a third mode of operation, hydraulic fluid is introduced under pressure into at least the first and second ancillary piston cylinder assemblies, thereby causing at least the first and second pistons to urge the platen in the rearward non-compression direction
[0026] In a second aspect, the present invention is directed to a feeder apparatus for advancing a compressible material, comprising:
[0027] a first piston cylinder assembly having a feedstock inlet suitable for receiving a compressible material;
[0028] a second piston cylinder assembly configured to receive material from the first piston cylinder assembly;
[0029] a third cylinder having a third cylinder ram arranged to travel therein, the third cylinder configured to receive material from the second piston cylinder assembly; and
[0030] the hydraulic circuit according to claim 1 ; wherein:
[0031] the third cylinder ram is connected to the platen so as to travel therewith.
[0032] In a third aspect, the present invention is directed to a reactor comprising the aforementioned feeder apparatus, a plug disintegrator assembly and a reactor feed screw assembly, wherein: the third cylinder is connected to the reactor via the plug disintegrator assembly and the reactor feed screw assembly, to thereby provide a compressed plug of compressible material to the reactor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] For a better understanding of the present invention and to show how the same may be carried out in practice, reference will now be made to the accompanying drawings, in which:
[0034] FIG. 1 is a diagrammatic representation of the prior art plug feeder system;
[0035] FIG. 2 illustrates an advancement stage of the hydraulic circuit of a system in accordance with one embodiment of the present invention;
[0036] FIG. 3 illustrates a pressurization stage of the hydraulic circuit of a system in accordance with one embodiment of the present invention;
[0037] FIG. 4 illustrates a retraction stage of the hydraulic circuit of a system in accordance with one embodiment of the present invention;
[0038] FIG. 5 presents a flow chart for controlling the advancement, pressurization, and retraction of the energy-efficient hydraulic compression plug formation process;
[0039] FIG. 6 presents a table of states of various circuit elements in the different operational modes of the hydraulic circuit; and
[0040] FIG. 7 illustrates a schematic view of a second embodiment of a hydraulic circuit in which the ancillary cylinders assemblies are in a master-slave arrangement.
DETAILED DESCRIPTION
[0041] FIG. 2 illustrates a preferred embodiment of the present invention wherein the third piston cylinder assembly ( 08 ) of the prior art is replaced by an inventive hydraulic compression circuit ( 214 ). The hydraulic compression circuit ( 214 ) includes the following: a first ancillary piston cylinder assembly ( 140 ), a second ancillary piston cylinder assembly ( 164 ), a primary third hydraulic cylinder assembly ( 189 ), a platen ( 212 ) driven by all three assemblies ( 140 , 164 and 189 ), and a primary ram ( 206 ) coupled to the platen ( 212 ). The primary ram ( 206 ) can be considered to replace the prior art third piston ram ( 90 ) seen in FIG. 1 . The first and second piston cylinder assemblies ( 140 , 164 ) act in unison to advance or retract the platen ( 212 ) which in turn affects the advancement or retraction of the primary third hydraulic cylinder assembly ( 189 ) while also driving the primary ram ( 206 ), affixed to the opposing side of the platen ( 212 ), for the creation of one or more plugs of compressible material for feeding into a reactor ( 104 ).
[0042] The first ancillary piston cylinder assembly ( 140 ) is comprised of: a first ancillary hydraulic cylinder ( 142 ), a first ancillary hydraulic cylinder front cylinder space ( 144 ), a first ancillary hydraulic cylinder rear cylinder space ( 146 ), a first ancillary hydraulic cylinder front connection port ( 148 ), a first ancillary hydraulic cylinder rear connection port ( 151 ), a first ancillary hydraulic cylinder piston ( 154 ), and a first ancillary piston rod ( 152 ). The first ancillary piston rod ( 152 ) is connected to the platen ( 212 ).
[0043] Advancement and retraction of the piston ( 154 ) and rod ( 152 ) are with respect to the reference point created by the first ancillary hydraulic cylinder static end ( 160 ). The piston ( 154 ) defines ancillary front cylinder space ( 144 ) and ancillary rear cylinder space ( 146 ) in the first ancillary hydraulic cylinder ( 142 ). Each space contains hydraulic fluid.
[0044] The second ancillary piston cylinder assembly ( 164 ) is functionally identical to the first ancillary piston cylinder assembly ( 140 ) and is comprised of: a second ancillary hydraulic cylinder ( 166 ), a second ancillary hydraulic cylinder front cylinder space ( 168 ), a second ancillary hydraulic cylinder rear cylinder space ( 170 ), second ancillary hydraulic cylinder front connection port ( 172 ), a second ancillary hydraulic cylinder rear connection port ( 174 ), a second ancillary hydraulic cylinder piston ( 178 ), and a second ancillary piston rod ( 176 ). The second ancillary piston rod ( 176 ) is connected to the platen ( 212 ).
[0045] Advancement and retraction of the piston ( 178 ) and rod ( 176 ) are with respect to the reference point created by the second ancillary hydraulic cylinder static end ( 186 ). The piston ( 178 ) defines ancillary front cylinder space ( 168 ) and ancillary rear cylinder space ( 170 ) in the second ancillary hydraulic cylinder ( 166 ). Each space contains hydraulic fluid.
[0046] Piston rods ( 152 ) and ( 176 ) are connected to pistons ( 154 ) and ( 178 ), respectively, which are in sealing engagement with the walls of the cylinders ( 142 ) and ( 166 ), respectively. The system could be expanded to include any number of ancillary hydraulic cylinders, if such was required.
[0047] The primary third hydraulic cylinder assembly ( 189 ) is comprised of: a primary third hydraulic cylinder ( 190 ), a primary third hydraulic cylinder front cylinder space ( 192 ), a primary third hydraulic cylinder rear cylinder space ( 194 ), a primary third hydraulic cylinder front connection port ( 196 ), a primary third hydraulic cylinder rear connection port ( 198 ), a primary third hydraulic cylinder piston ( 202 ), and a primary third piston rod ( 201 ). The primary third piston rod ( 201 ) is connected to the platen ( 212 ).
[0048] The primary third piston rod ( 201 ) is connected to the primary third hydraulic cylinder piston ( 202 ) which is in sealing engagement with the walls of the primary third hydraulic cylinder ( 190 ). The piston ( 202 ) defines the front cylinder space ( 192 ) and the rear cylinder space ( 194 ) in the third cylinder ( 190 ). Each space contains hydraulic fluid.
[0049] At least one of the cylinders has a sensor that provides feedback signal to a distributed control system (DCS), programmable logic controller (PLC), or motion controller transmitting or indicating the exact position of the associated piston along its entire linear stroke (from start position, L 0 , to end the position, L 2 ).
[0050] The sensor outputs a signal reflective of a position of third piston ( 202 ). This may be done by measuring the position of the primary ram ( 206 ), the position of the platen ( 212 ), the position of any of the piston rods ( 152 , 176 , 201 ), or the positions of any of the pistons ( 154 , 178 , 202 ). It is understood that measuring any one of these can provide information about the position of any of the others, since the primary ram, the platen, the piston rods and the pistons all move together.
[0051] In a preferred embodiment, the sensor comprises a linear transducer ( 193 ) having a first end attached to a fixed (non-moving) portion of one of the hydraulic cylinder assemblies ( 140 , 164 , 189 ) and a second end attached to a movable portion of said one of the hydraulic cylinder assemblies ( 140 , 164 , 189 ), or to the platen ( 212 ) or the primary ram ( 206 ). In a preferred embodiment, the linear transducer ( 193 ) is attached to the primary third hydraulic cylinder static end ( 208 ). The linear transducer ( 193 ) protrudes through the primary third hydraulic cylinder rear cylinder space ( 194 ) to be accommodated within an opening ( 191 ) deliberately ‘gun-drilled’ in the primary third piston rod ( 201 ) and primary third hydraulic cylinder piston ( 202 ), to precisely control and monitor the movement of the platen ( 212 ) and primary ram ( 206 ).
[0052] In an alternate embodiment, the sensor that is used for sensing and indication of the stroke position of the primary third piston rod ( 201 ), that is, indicating the amount of extension or the position of the piston rod ( 201 ) from a reference may be installed exterior to the hydraulic cylinder ( 142 ) (not shown) so it can be installed and removed without disassembly of the cylinder. In either embodiment, the single output by the linear transducer ( 193 ) reflects the position of third piston ( 202 ).
[0053] The hydraulic compression circuit ( 214 ) as depicted in FIG. 2 also includes: a primary tank ( 2000 ), a surge tank ( 1000 ), a hydraulic pump ( 238 ), and a plurality of valves. The plurality of valves includes an ancillary cylinder rear valve ( 150 ), an ancillary cylinder front valve ( 200 ), a primary third cylinder rear supply valve ( 300 ), a primary third cylinder rear surge valve ( 350 ), a primary third cylinder front surge valve ( 400 ), and a primary third cylinder front drain valve ( 450 ).
[0054] The ancillary cylinder rear valve ( 150 ) includes an ancillary cylinder rear supply port ( 150 A), an ancillary cylinder rear drain port ( 150 B), and an ancillary cylinder rear common port ( 150 C). The ancillary cylinder front valve ( 200 ) includes an ancillary cylinder front supply port ( 200 A), an ancillary cylinder front drain port ( 200 B), and an ancillary cylinder front common port ( 200 C).
[0055] A pump suction line ( 240 ) connects the primary tank ( 2000 ) with the hydraulic pump ( 238 ). A pump discharge line ( 236 ) connects the outlet of the hydraulic pump ( 238 ) with: the ancillary cylinder front supply port ( 200 A) through the ancillary cylinder front supply line ( 232 ); the ancillary cylinder rear supply port ( 150 A) through the ancillary cylinder rear supply line ( 230 ); and the primary third cylinder rear supply valve ( 300 ) through the primary third cylinder rear supply line ( 226 ). The hydraulic pump ( 238 ) may provide pressurized fluid to any of these three valves through their respective transfer lines.
[0056] The primary third hydraulic cylinder rear connection port ( 198 ) is in communication with the primary third cylinder rear supply line ( 226 ) where the open or closed position of the primary third cylinder rear supply valve ( 300 ) restricts the availability of the pressurized fluid transferred from the discharge of the hydraulic pump ( 238 ) to the primary third hydraulic cylinder rear cylinder space ( 194 ).
[0057] The primary third hydraulic cylinder rear connection port ( 198 ) is also in communication with the surge tank ( 1000 ) via a primary third cylinder rear surge line ( 224 ) with the primary third cylinder rear surge valve ( 350 ) interposed therebetween.
[0058] The primary third hydraulic cylinder front connection port ( 196 ) is in communication with the surge tank ( 1000 ) via a primary third cylinder front surge line ( 222 ) with the primary third cylinder front surge valve ( 400 ) interposed therebetween.
[0059] The primary third hydraulic cylinder front connection port ( 196 ) is also in communication with the primary tank ( 2000 ) via a primary third cylinder front drain line ( 220 ) with the primary third cylinder front drain valve ( 450 ) interposed therebetween.
[0060] Ancillary front cylinder space drain lines ( 252 a , 252 b ) connect both the first ancillary hydraulic cylinder front connection port ( 148 ), and the second ancillary hydraulic cylinder front connection port ( 172 ), respectively, with the ancillary cylinder front common port ( 200 C) of the ancillary cylinder front valve ( 200 ), via the shared ancillary front cylinder space drain line ( 252 ).
[0061] Ancillary rear cylinder space drain lines ( 248 a , 248 b ) connect both the first ancillary hydraulic cylinder rear connection port ( 151 ), and the second ancillary hydraulic cylinder rear connection port ( 174 ), respectively, with the ancillary cylinder rear common port ( 150 C) of the ancillary cylinder rear valve ( 150 ), via the shared ancillary rear cylinder space drain line ( 248 ).
[0062] As seen in the arrangement of FIG. 2 , although they share the ancillary cylinder drain lines ( 248 , 252 ), the two ancillary cylinders ( 142 , 166 ) are coupled in hydraulic parallel with the primary tank ( 2000 ) in the sense that the hydraulic fluid is not configured to flow between the first and second ancillary piston cylinders ( 142 , 166 ).
[0063] The ancillary cylinder front drain port ( 200 B) of the ancillary cylinder front valve ( 200 ) is connected to the primary tank ( 2000 ) through an ancillary front cylinder space drain line ( 254 ).
[0064] The ancillary cylinder rear drain port ( 150 B) of the ancillary cylinder rear valve ( 150 ) is connected to the primary tank ( 2000 ) through an ancillary rear cylinder space drain line ( 255 ).
[0065] FIGS. 2, 3 and 4 , in conjunction with FIGS. 5 and 6 , describe the various modes (steps) of operation of the hydraulic circuit ( 214 ). FIG. 5 shows a Flow Chart and FIG. 6 shows a Detailed Sequencing Chart, which together depict the valve sequencing, sequence mode/step characteristics, and overall approach of the inventive method. It is understood that the bold arrows in each of FIGS. 2, 3 and 4 indicated open flow paths for the hydraulic fluid, as determined by positions of the various valves.
[0066] Advancement Sequence Mode ( 1500 )
[0067] FIG. 2 shows the hydraulic compression circuit ( 214 ) in the advancement sequence mode/step. In the advancement sequence mode ( 1500 ), advancement of the first ancillary piston cylinder assembly ( 140 ) and the second ancillary piston cylinder assembly ( 164 ) take place while the primary third hydraulic cylinder assembly ( 189 ) is isolated from the hydraulic pump ( 238 ).
[0068] Isolating the primary third hydraulic cylinder rear cylinder space ( 194 ) from the hydraulic pump ( 238 ) during the advancement sequence step ( 1500 ) has certain advantages related to the energy efficiency of the prior art feeding apparatus ( 02 ).
[0069] A high power consumption and unfavorable energy efficiency is associated with the third hydraulic cylinder ( 74 ) of the prior art feeding apparatus ( 02 ) since it is the largest of the three hydraulic cylinder assemblies and requires the most volume of hydraulic fluid for driving its piston.
[0070] The diameters of the first ancillary piston cylinder assembly ( 140 ) and the second ancillary piston cylinder assembly ( 164 ), specifically the pressure-receiving surface area of each of their pistons ( 154 , 176 ) are of a lesser diameter than that of the primary third hydraulic cylinder piston ( 202 ).
[0071] Utilization of a platen ( 212 ) and two or more ancillary piston cylinder assemblies ( 140 , 164 ) with diameters smaller than that of the primary third hydraulic cylinder assembly ( 189 ) reduces the volume of fluid required to advance the primary ram ( 206 ). This results in a more economical process for the compression of carbonaceous material into a plug of desired length and density.
[0072] In the advancement sequence mode ( 1500 ), hydraulic fluid is drawn from the primary tank ( 2000 ) and transferred through ancillary cylinder rear supply line ( 230 ), ports ( 150 A, 150 C) of ancillary cylinder rear valve ( 150 ), and ancillary rear cylinder space drain lines ( 248 , 248 a , 248 b ) into ancillary rear cylinder spaces ( 146 , 170 ) of the first ancillary piston cylinder assembly ( 140 ) and second ancillary piston cylinder assembly ( 164 ).
[0073] Also in the advancement sequence step ( 1500 ), hydraulic fluid is displaced from the ancillary front cylinder spaces ( 144 , 168 ) of the first ancillary piston cylinder assembly ( 140 ) and second ancillary piston cylinder assembly ( 164 ) and is returned to the primary tank ( 2000 ) through ancillary front cylinder space drain lines ( 252 , 252 a , 252 b ), ports ( 200 C, 200 B) of ancillary cylinder front valve ( 200 ) and ancillary front cylinder space drain line ( 254 ).
[0074] The hydraulic fluid advances ancillary pistons ( 154 , 178 ) which in turn advances the motion of the platen ( 212 ) and primary ram ( 206 ) while also advancing the motion of the primary third piston rod ( 201 ) and primary third hydraulic cylinder piston ( 202 ).
[0075] Additionally, in the advancement sequence step ( 1500 ), the primary cylinder front and rear supply valves ( 300 , 450 ) are closed, while the primary cylinder front and rear surge valves ( 350 , 450 ) are open. This allow the primary third piston rod ( 201 ) and the primary third hydraulic cylinder piston ( 202 ) to advance while the primary third hydraulic cylinder front cylinder space ( 192 ) and primary third hydraulic cylinder rear cylinder space ( 194 ) are isolated from the discharge pressure of the hydraulic pump ( 238 ).
[0076] Hydraulic fluid displaced from the primary third hydraulic cylinder front cylinder space ( 192 ) is allowed to freely flow into the surge tank ( 1000 ) through primary third cylinder front surge line ( 222 ) and open front surge valve ( 400 ). In a similar vein, hydraulic fluid from the surge tank ( 1000 ) is allowed to freely flow into the primary third hydraulic cylinder rear cylinder space ( 194 ) through the primary third cylinder rear surge line ( 224 ) and open rear surge valve ( 350 ). Thus, by virtue of connection to the platen ( 212 ), the primary third piston rod ( 201 ) and the primary third hydraulic cylinder piston ( 202 ) go along for the ride, as the hydraulic fluid advances the ancillary pistons ( 154 , 178 ).
[0077] Hydraulic fluid continues to be transferred to the ancillary rear cylinder spaces ( 146 , 170 ) of the first ancillary piston cylinder assembly ( 140 ) and second ancillary piston cylinder assembly ( 164 ) until the linear transducer ( 193 ) indicates that a first predetermined set-point of the intermediate stroke length position (L 1 ) has been reached. The output of the linear transducer ( 193 ) is provided to a controller ( 500 ). In response to the output from the linear transducer ( 193 ) indicating that the first predetermined set-point has been reached, the controller ( 500 ) is configured to control the various valves such that the system transitions from the advancement sequence mode ( 1500 ) to the pressurization sequence mode ( 1530 ).
[0078] Pressurization Sequence Mode ( 1530 )
[0079] FIG. 3 shows the hydraulic compression circuit ( 214 ) in the pressurization sequence mode/step ( 1530 ). In contrast to the advancement sequence mode, in the pressurization sequence mode, the primary cylinder front and rear supply valves ( 300 , 450 ) are open, while the primary cylinder front and rear surge valves ( 350 , 450 ) are closed. This isolates the primary third cylinder assembly ( 189 ) from the surge tank ( 1000 ) and allows hydraulic fluid to flow from (a) the primary tank ( 2000 ) to the primary third hydraulic cylinder rear cylinder space ( 194 ) and, from (b) the primary third hydraulic cylinder front cylinder space ( 192 ) to the primary tank ( 2000 ). As such, the primary third hydraulic cylinder rear cylinder space ( 194 ) is available to the pressurized discharge of the hydraulic pump ( 238 ), in addition to the ancillary rear cylinder spaces ( 146 , 170 ) of the first ancillary piston cylinder assembly ( 140 ) and second ancillary piston cylinder assembly ( 164 ). In another embodiment the surge tank ( 1000 ) may not be used but one common tank, such as the primary tank ( 2000 ), may be used as the sole storage reservoir and surge tank for the hydraulic compression circuit ( 214 ), given appropriate valve placement and control.
[0080] In the pressurization sequence mode ( 1530 ), hydraulic fluid is transferred to all the rear cylinder spaces ( 146 , 170 , 194 ) of the ancillary and primary piston cylinder assemblies ( 140 , 164 , 189 ) until the linear transducer ( 193 ) indicates that a second predetermined set-point of the maximum stroke length position (L 2 ) has been reached. The output of the linear transducer ( 193 ) is provided to the aforementioned controller ( 500 ). In response to the output from the linear transducer ( 193 ) indicating that the second predetermined set-point has been reached, the controller ( 500 ) is configured to control the various valves such that the system transitions from the pressurization sequence mode ( 1530 ) to the retraction sequence mode ( 1560 ).
[0081] Retraction Sequence Mode ( 1560 )
[0082] FIG. 4 represents the valve sequencing and flow path of hydraulic fluid in the retraction sequence mode ( 1560 ).
[0083] In the retraction sequence mode ( 1560 ), the primary cylinder front and rear supply valves ( 300 , 450 ) are closed, and the primary cylinder front and rear surge valves ( 350 , 400 ) are open, much like in the advancement sequence mode ( 1500 ). However, relative to their corresponding positions in the advancement sequence mode ( 1500 ), in the retraction sequence mode ( 1560 ), the positions of ancillary supply ports ( 150 A, 200 A) and the positions ancillary drain ports ( 150 B, 200 B) of the ancillary cylinder valves ( 150 , 200 ) are reversed.
[0084] Hydraulic fluid is transferred from the hydraulic pump ( 238 ) through ancillary cylinder front supply line ( 232 ) and ports ( 200 A, 200 C) of ancillary cylinder front valve ( 200 ) into the ancillary front cylinder spaces ( 144 , 168 ) of the first ancillary piston cylinder assembly ( 140 ) and second ancillary piston cylinder assembly ( 164 ).
[0085] Hydraulic fluid displaced from the primary third hydraulic cylinder rear cylinder space ( 194 ) is allowed to freely flow into the surge tank ( 1000 ) through rear surge line ( 224 ) and open rear surge valve ( 350 ). Accordingly, hydraulic fluid from the surge tank ( 1000 ) is allowed to freely flow into the primary third hydraulic cylinder front cylinder space ( 192 ) through front surge line ( 222 ) and open front surge valve ( 400 ).
[0086] Hydraulic fluid displaced from the ancillary rear cylinder spaces ( 146 , 170 ) of the first ancillary piston cylinder assembly ( 140 ) and second ancillary piston cylinder assembly ( 164 ) is diverted back to the primary tank ( 2000 ) through ancillary cylinder rear drain lines ( 248 , 248 a , 248 b ), ports 150 C and 150 B of ancillary cylinder rear valve ( 150 ), and ancillary rear cylinder space drain line ( 255 ).
[0087] Hydraulic fluid entering the ancillary front cylinder spaces ( 144 , 168 ) causes the first and second ancillary hydraulic cylinder pistons ( 154 ) and ( 178 ) to retract, thus pulling the platen ( 212 ). Due to motion of the platen ( 212 ), the primary ram ( 206 ), the primary third piston rod ( 201 ) and the primary third hydraulic cylinder piston ( 202 ) freely retract as well.
[0088] Hydraulic fluid is transferred to the ancillary front cylinder spaces ( 144 , 168 ) of the first ancillary piston cylinder assembly ( 140 ) and second ancillary piston cylinder assembly ( 164 ), thereby causing retraction of the primary third piston cylinder assembly ( 189 ), until the linear sensor transducer ( 193 ) indicates a predetermined third set-point of the stroke starting position (L 0 ) has been reached. The output of the linear transducer ( 193 ) is provided to the aforementioned controller ( 500 ). In response to the output from the linear transducer ( 193 ) indicating that the third predetermined set-point has been reached, the controller ( 500 ) may be configured to control the various valves such that the system transitions from the retraction sequence mode ( 1560 ) to the advancement sequence mode ( 1500 ), to repeat the compression process.
[0089] FIG. 7 shows an alternate embodiment in which the ancillary cylinders ( 142 , 166 ) are in a master-slave arrangement. In the master-slave arrangement, hydraulic fluid flows from the front cylinder space of a first ancillary cylinder to the rear cylinder space of a second ancillary cylinder. In this sense, the two ancillary cylinders ( 142 , 166 ) are coupled in hydraulic series, with the hydraulic fluid configured to flow between the first and second ancillary piston cylinders ( 142 166 ).
[0090] Although the present invention has been described with reference to certain embodiments, it should be understood that various alterations and modifications could be made without departing from the spirit or scope of the invention as hereinafter claimed.
TABLE OF REFERENCE NUMERALS
[0000]
stroke starting position (L 0 )
intermediate stroke length position (L 1 )
maximum stroke length position (L 2 )
feeding apparatus ( 02 )
first piston cylinder assembly ( 04 )
second piston cylinder assembly ( 06 )
third piston cylinder assembly ( 08 )
first cylinder ( 10 )
second cylinder ( 12 )
third cylinder ( 14 )
plug disintegrator assembly ( 18 )
reactor feed screw assembly ( 22 )
first hydraulic cylinder ( 24 )
first hydraulic cylinder front cylinder space ( 26 )
first hydraulic cylinder rear cylinder space ( 28 )
first hydraulic cylinder front connection port ( 30 )
first hydraulic cylinder rear connection port ( 32 )
first piston rod ( 34 )
first hydraulic cylinder piston ( 36 )
first hydraulic cylinder flange ( 38 )
first piston ram ( 40 )
inlet means ( 42 )
first cylinder first flange ( 44 )
first cylinder second flange ( 46 )
second hydraulic cylinder ( 48 )
second hydraulic cylinder front cylinder space ( 50 )
second hydraulic cylinder rear cylinder space ( 52 )
second hydraulic cylinder front connection port ( 54 )
second hydraulic cylinder rear connection port ( 56 )
second piston rod ( 58 )
second hydraulic cylinder piston ( 60 )
second hydraulic cylinder flange ( 62 )
second piston ram ( 64 )
second cylinder first flange ( 66 )
second cylinder second flange ( 68 )
second cylinder third flange ( 70 )
second cylindrical pipe branch opening ( 72 )
third hydraulic cylinder ( 74 )
third hydraulic cylinder front cylinder space ( 76 )
third hydraulic cylinder rear cylinder space ( 78 )
third hydraulic cylinder front connection port ( 80 )
third hydraulic cylinder rear connection port ( 82 )
third piston rod ( 84 )
third hydraulic cylinder piston ( 86 )
third hydraulic cylinder flange ( 88 )
third piston ram ( 90 )
third cylinder first flange ( 92 )
third cylinder second flange ( 94 )
third cylinder third flange ( 96 )
third cylindrical pipe branch opening ( 98 )
plug ( 100 )
fluidized bed ( 102 )
reactor ( 104 )
first ancillary piston cylinder assembly ( 140 )
first ancillary hydraulic cylinder ( 142 )
first ancillary hydraulic cylinder front cylinder space ( 144 )
first ancillary hydraulic cylinder rear cylinder space ( 146 )
first ancillary hydraulic cylinder front connection port ( 148 )
ancillary cylinder rear valve ( 150 )
ancillary cylinder rear supply port ( 150 A)
ancillary cylinder rear drain port ( 150 B)
ancillary cylinder rear common port ( 150 C)
first ancillary hydraulic cylinder rear connection port ( 151 )
first ancillary piston rod ( 152 )
first ancillary hydraulic cylinder piston ( 154 )
first ancillary hydraulic cylinder static end ( 160 )
second ancillary piston cylinder assembly ( 164 )
second ancillary hydraulic cylinder ( 166 )
second ancillary hydraulic cylinder front cylinder space ( 168 )
second ancillary hydraulic cylinder rear cylinder space ( 170 )
second ancillary hydraulic cylinder front connection port ( 172 )
second ancillary hydraulic cylinder rear connection port ( 174 )
second ancillary piston rod ( 176 )
second ancillary hydraulic cylinder piston ( 178 )
second ancillary hydraulic cylinder static end ( 186 )
primary third hydraulic cylinder assembly ( 189 )
primary third hydraulic cylinder ( 190 )
opening ( 191 )
primary third hydraulic cylinder front cylinder space ( 192 )
linear transducer ( 193 )
primary third hydraulic cylinder rear cylinder space ( 194 )
primary third hydraulic cylinder front connection port ( 196 )
primary third hydraulic cylinder rear connection port ( 198 )
ancillary cylinder front valve ( 200 )
ancillary cylinder front supply port ( 200 A)
ancillary cylinder front drain port ( 200 B)
ancillary cylinder front common port ( 200 C)
primary third piston rod ( 201 )
primary third hydraulic cylinder piston ( 202 )
primary ram ( 206 )
primary third hydraulic cylinder static end ( 208 )
platen ( 212 )
hydraulic compression circuit ( 214 )
primary third cylinder front drain line ( 220 )
primary third cylinder front surge line ( 222 )
primary third cylinder rear surge line ( 224 )
primary third cylinder rear supply line ( 226 )
ancillary cylinder rear supply line ( 230 )
ancillary cylinder front supply line ( 232 )
pump discharge line ( 236 )
hydraulic pump ( 238 )
pump suction line ( 240 )
shared ancillary rear cylinder space drain line ( 248 )
ancillary rear cylinder space drain line ( 248 a )
ancillary rear cylinder space drain line ( 248 b )
shared ancillary front cylinder space drain line ( 252 )
ancillary front cylinder space drain line ( 252 a )
ancillary front cylinder space drain line ( 252 b )
ancillary front cylinder space drain line ( 254 )
ancillary rear cylinder space drain line ( 255 )
primary third cylinder rear supply valve ( 300 )
forward compression direction ( 310 )
rearward non-compression direction ( 312 )
primary third cylinder rear surge valve ( 350 )
primary third cylinder front surge valve ( 400 )
primary third cylinder front drain valve ( 450 )
controller ( 500 )
surge tank ( 1000 )
primary tank ( 2000 )
advancement sequence step 1500
pressurization sequence step 1530
retraction sequence step 1560 | A feeder system for advancing a compressible material has a hydraulic circuit associated with a final compression stage. The hydraulic circuit includes a platen attached to a primary ram configured to travel within a primary cylinder. The platen is operatively connected to a main piston cylinder assembly and at least two ancillary piston cylinder assemblies. In a first mode of operation, the hydraulic circuit forces the ancillary piston cylinder assemblies to advance the platen and ram in a forward compression direction until they reach a first predetermined position between travel extremes, while the main piston cylinder assembly passively travels along in the forward compression direction. Once the first predetermined position is reached, in a second mode of operation, the hydraulic circuit additionally forces the main piston cylinder assembly to compress the compressible material. In a third mode of operation, the hydraulic circuit retracts the platen and primary ram. | 1 |
TECHNICAL FIELD
The invention herein resides in the art of material dispensing systems which monitor and control the characteristics of the bead of material being dispensed. More particularly, the present invention relates to a sensor which transmits and receives sound waves to determine the height and width of material that has been dispensed. Specifically, the present invention relates to a dispensing system with a closed loop feedback control for adjusting the dispensing flow of the material based upon bead characteristics monitored by a sensor.
BACKGROUND OF THE INVENTION
This invention relates generally to the dispensing of fluid materials onto substrates. More particularly, the invention relates to the detection and/or monitoring of a bead of material which has been deposited onto a substrate. Specifically, this invention is applicable to the detection of the presence of discontinuities associated with a deposited bead of material, such as, for example, a bead of an adhesive, sealant, or caulk, as well as determining other qualities of the deposited bead, such as its height, cross-section, or the amount of material that has been dispensed. This invention is especially useful in the monitoring of a bead of material dispensed onto the periphery of window glass, such as a windshield in preparation for adhesively bonding the glass to the body flange of a vehicle.
The presence of an air bubble passing through a nozzle of a dispensing system or a reduction in the material supply pressure may cause a disruption in the flow rate of material being dispensed so as to produce a discontinuity or deformation in the bead deposited upon the substrate. If the air bubble or the reduction in the material supply pressure or flow rate is small, the effect on the resulting bead may be minimal. However, if the air bubble is large or the material supply pressure is insufficient, the effect may produce a significant discontinuity in the bead, or a bead having an insufficient height or cross-section. In some applications, discontinuities in the bead may not be critical, however, in others they may be. For example, discontinuities in a bead of the adhesive/sealant applied to a windshield may not only affect its ability to act as a moisture barrier, but it also may affect the strength of the bond of the windshield in the vehicle.
Attempts have been made to detect gaps in dispensed beads automatically as opposed to an operator's visual inspection. This has included monitoring pressure fluctuation within the system as set forth in U.S. Pat. Nos. 4,662,540 and 5,182,938, as well as monitoring the vibration of the dispenser, such as set forth in U.S. Pat. No. 5,086,640. These patents attempt to detect a discontinuity in the bead before the bead is actually deposited onto the substrate. They only infer that a discontinuity has occurred, as opposed to verifying that a discontinuity has actually occurred in the deposited bead.
Although not in the assembly of automobile glass, sensors have been used to monitor energy radiating from the deposited bead by utilizing an infrared sensor, such as shown in U.S. Pat. No. 5,026,989. However, this device must be used with a heated adhesive, such as a hot melt adhesive. It therefore would not be useful with room temperature adhesives commonly used in the automotive industry.
German Utility Patent G 91 10 924.8 and U.S. Pat. No. 4,376,244 generally teach directing a beam of light onto a substrate before the adhesive is applied and directing the beam of light onto the substrate after the drop of adhesive has been applied. This device monitors only the presence or absence of adhesive on the substrate and does not provide a determination if sufficient material, such as evident by its height and/or width, has been deposited. Furthermore, this device requires a reflective substrate, such as metal or veneer, and may not be suitable for all substrates, such as glass.
Beads that are continuous, but not of a sufficient height or width, may also be undesirable because the ability of the bead to act as a moisture barrier and/or the strength of the bond of the window glass to the vehicle may be affected. In like manner, beads exceeding a certain height or width may also be undesirable. Therefore, it is desirable to be able to determine not only discontinuities in the bead, but also to detect the quality, such as the height, width, etc. of the deposited bead.
SUMMARY OF THE INVENTION
It is, therefore, among the aspects of this invention to provide for the detection of gaps or discontinuities in a dispensed bead on a substrate.
It is also an aspect of one embodiment of this invention to provide for the monitoring of a bead dispensed upon a substrate to detect beads not having a desirable bead height and/or cross-section.
It is also an aspect of this invention, according to one embodiment, to provide for the monitoring of a dispensed bead and to adjust the amount of material dispensed from a dispenser as a result of said monitoring.
The foregoing and other aspects of the invention, which shall become apparent as the detailed description proceeds, are achieved by a dispensing system for monitoring the characteristics of material dispensed onto a substrate, comprising: a supply of material; a nozzle for receiving said material from said supply of material and dispensing a bead of said material onto the substrate; and a sensor for monitoring the bead of dispensed material, wherein said sensor transmits and receives sound waves around an area of the dispensed material to determine if predetermined characteristics of the bead have been met.
Other aspects of the invention which will be become apparent herein are achieved by a dispensing system which controls the flow of material onto a substrate, comprising: a nozzle for dispensing a bead of material onto the substrate; a non-contacting sensor that monitors at least one predetermined characteristic of said bead of material; and a control circuit connected to said non-contacting sensor for regulating the flow of material based upon said at least one predetermined characteristic.
Still other aspects of the invention are attained by a dispensing system, comprising: a control circuit; a nozzle for dispensing a supply of material onto a substrate in the form of a bead, wherein the flow and shape of said bead is determined by said control circuit; and a sensor connected to said control circuit for providing characteristics of said bead to said control circuit for analysis.
DESCRIPTION OF THE DRAWINGS
The following is a brief description of the drawings in which like parts may bear like reference numerals and in which:
FIG. 1 is a schematic view of the application of a bead of sealant onto the marginal edge of a windshield of a vehicle in accordance with one embodiment of the invention used in conjunction with an industrial robot;
FIG. 2 is an enlarged fragmentary portion of FIG. 1;
FIG. 3 is an enlarged cross-sectional view of the dispensed bead illustrating the transmitted and received waves from a sensor;
FIGS. 4A and 4B illustrate the transmission and reception of an ultrasonic transceiver (4A) and of a shock wave transceiver (4B);
FIG. 5 is a schematic of a portion of a control circuit according to one embodiment of the invention; and
FIG. 6 is a schematic of another portion of the control circuit for adjusting the material dispensed.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIGS. 1 and 2, there is illustrated a dispensing system, shown generally as reference numeral 10, used in conjunction with an industrial robot 12, such as, for example, the type employed in the assembly of automobiles or other vehicles. The dispensing system includes a dispenser 14 which is coupled via hose 16 to a supply of fluid material 18. The dispenser 14 includes a nozzle 20 for dispensing a bead of material 22 onto a substrate 24. The bead of material 18 may be, for example, an adhesive, a sealant, or a caulk. In one particular application, the substrate 24 may be glass, such as a windshield for use in vehicles. Furthermore, the bead 22 may be an adhesive, such as illustrated in EP 379 908, assigned to Essex Specialty Products, Inc., which is used in the assembly of automobile window glass.
Preferably, a sensor 26 for monitoring the dispensed bead 22 on the substrate, is carried by the dispenser 14. For example, the sensor 26 may be mounted to the nozzle 20 of the dispenser 14 by a clamping mechanism 28 or other suitable mounting means. The sensor 26 is coupled via cable 30 to electrical control circuitry, shown generally as reference numeral 32.
As seen in FIG. 3, the sensor 26 is a transducer for transmitting and receiving ultrasonic waves or focused shock waves. The sensor 26 is useful for measuring the distance between the sensor and an object, by generating a pressure wave and then receiving an echo as a return pressure wave after the created wave is reflected back to the sensor 26. The time interval between transmitting a pressure wave and receiving an echo or a reflected wave by the sensor 26 is a function of the distance of the bead 22 from the sensor. The time interval between the transmitted wave 34 and the return echo 36 can be electrically processed to produce a voltage signal indicative of distance of the object from the sensor 26.
An ultrasonic pulse or shock wave 34, shown generally as a plurality of parallel rays 38, is transmitted orthogonally toward the substrate 24. The individual rays or wavelets will strike either the bead 22 or the substrate 24 and, depending upon the angle of incidence, will either be reflected back toward the sensor 26 as depicted by rays 40 or will be deflected beyond the sensor's receiving range, such as illustrated by rays 42. For beads 22 having a triangular cross-section, the rays which strike an apex 44 of the bead 22 will be reflected back and received by the sensor 26 before the rays that have been reflected from the substrate 24. Furthermore, the rays 42 which strike sides 46 of the bead 22 will not be received by the sensor due to their angular orientation relative to the sensor 26. This results in two separate echoes being received by the sensor 26, one corresponding to the top or apex 44 of the bead while the other corresponds to the substrate 24. As such, the height (h) of bead 22 can be determined by the following equation:
h=1/2 Δt×c (1)
Where Δt is the time interval between receipt of the first echo from the apex 44 and the second echo from the substrate 24, and where c is the speed of sound. The 1/2 factor is employed to account for the propagation time of the transmitted rays 38 and the reflected rays 40.
This is further understood with reference to FIGS. 4A and 4B, wherein the sensor 26 is respectively employed to generate either an ultrasonic transmission 48a of a certain duration as associated with an ultrasonic transducer or a pulse 48b of a certain duration as associated with a shock wave transducer. The time interval between the transmission signals 48a and 48b, and corresponding return echoes 50a and 50b from the bead is noted at time t1. The return echoes 50a, 50b have an amplitude 51 of the bead echo (ABE). The time interval between the transmission signals 48a, 48b and corresponding return echoes 52a, 52b from the substrate is noted at t2. Likewise, the return echoes 52a, 52b have an amplitude 53 of the substrate echo (ASE). As such, the difference between t2 and t1 equals Δt.
To determine the base or width of a bead 22, the amplitude of the bead echo signal 50 and substrate echo signal 52 are employed. In particular, the amplitude 53 of the substrate echoes (ASE) 52a, 52b, that is the echo reflected from the substrate, is related proportionally to the area of the substrate exposed to the incident transmission or pulse 48a, 48b. The area of the substrate exposed to this transmission is inversely related to the width or base of the bead of material. In other words, less of the substrate is exposed to the transmission pulse if more of the substrate is covered with the bead 22. Therefore, the amplitude 53 of the substrate echoes (ASE) 52a, 52b is inversely related to the base of the bead. As a result, the amplitude 53 of the substrate echoes (ASE) 52a, 52b is greater with beads having a narrower base and is smaller with beads having a wider base.
Where the bead 22 has a triangular configuration, the cross-sectional area of the bead may be determined. The following equation provides a value for the area:
A=1/2 (base×height) (2)
Where the value for the base is determined by the amplitude 53 of the substrate echo 52a, 52b, and where the height is determined by equation (1) above. Based upon the foregoing, the quality of the dispensed bead may be determined from its height, width, or cross-sectional area by repetitively transmitting a signal 48a or 48b and monitoring the corresponding return signals of the bead echo signals 50a or 50b and the corresponding substrate echo signals 52a or 52b on a dispensed bead along its length.
Furthermore, by knowing the cross-sectional area of the bead throughout its length, the volumetric output of material dispensed during a dispensing cycle, such as applying the bead 22 about the periphery of the windshield 24, may be determined and corrections made to compensate for dispensing more or less than the desired amount of material during the dispensing cycle.
Utilizing the bead height and bead base in conjunction with a feedback control loop, the flow rate of material dispensing from the nozzle 20 may be adjusted to keep the bead within the targeted constraints. If however, the bead height, width, etc., falls below or above certain predetermined levels, alarms may be activated to indicate a defective bead.
In particular, FIG. 5 illustrates a monitoring portion of the dispensing system 10 and in particular control circuit 32. The sensor 26 is preferably a capacitance type electrostatic transducer, such as manufactured by Cleveland Machine Controls, Inc. of Cleveland, Ohio, which provides reflected signals or echoes from the dispensed bead 22 and the substrate 24 which are then passed through signal processing circuitry 60 such as described generally in U.S. Pat. Nos. 4,887,248 and 4,459,526, the disclosure of each being incorporated herein by reference. The signal processing circuitry 60 determines and generates signals corresponding to the amplitude of the bead and the substrate echoes ABE, ASE, as well as Δt.
It can be seen that the sensor 26 is operatively connected to the control circuit 32. Generally, the control circuit 32 includes the signal processing circuit 60, a bead measuring system 62 which includes a bead height processing circuit 64 and a bead width processing circuit 66, a sensor alarm circuit 68 and a statistical process control circuit 70. This portion of the control circuit 32 functions to process the information generated by the sensor 26 and determines whether the bead height and bead width of the dispensing bead 22 comply with predetermined characteristics. Additionally, control circuit 32 determines whether the dispensed bead 22 conforms to a desired shape while collecting data regarding the dispensing process for subsequent analysis.
In particular, the signal processing circuit 60 receives data from sensor 26 and, as discussed previously, generates a bead echo amplitude signal 51, a substrate echo amplitude signal 53 and the corresponding time interval signal Δt which is generally represented by the numeral 71.
The time interval signal 71 is received by the bead height processing circuit 64. The bead height processing circuit 64 includes a multiplier 72 which, as discussed before, multiplies the time interval 71 by a factor of the speed of sound divided by two so as to generate an analog height signal 73. The bead height processing circuit 64 then determines whether the height signal 73 is within predetermined upper and lower limits and, if not, an alarm signal is generated. In operation, the height signal 73 is received by an upper limit comparator 74 so as to generate a difference signal that is received by a timing circuit 76. The timing circuit 76 in turn generates a signal that is received by a timing comparator 78. The timing circuit 76 determines for what period of time the bead height exceeds the upper limit defined by comparator 74. As such, momentary or non-critical excesses in bead height will not generate the alarm signal. Therefore, if the comparator 78 determines that the predetermined upper limit has been exceeded for a time greater than a predetermined period of time, an alarm 80 is activated.
In a similar fashion, the height signal 73 is received by a lower limit comparator 82. The lower limit comparator 82 generates a signal that is received by a timing circuit 84 which generates a timing signal that is received by a timing comparator 86. As before, if the height signal 73 falls below a predetermined lower limit for a time greater than a predetermined period of time, an alarm 88 is activated accordingly. Those skilled in the art will also appreciate that the height signal 73 is passed on by the bead height processing circuit 64 to the sensor alarm circuit 68 and to the statistical process control system 70.
The bead width processing circuit 66 receives the substrate echo amplitude signal 53 to determine whether the width of the bead material 22 is within predetermined upper and lower limits and, if not, an alarm signal is generated. In particular, the substrate echo signal 53 is received by a bead width multiplier/converter 90 which generates an analog base signal 92. The base signal 92 is received by a comparator 94 to check the bead width against a predetermined upper limit. The comparator 94 then generates an appropriate signal that is received by a timing circuit 96 which provides a timing signal to a timing comparator 98. If the timing comparator 98 determines that the bead base exceeds a predetermined upper limit for a time greater than a predetermined period of time, an alarm 100 is activated.
In a similar manner, the base analog signal 92 is received by a lower limit comparator 102. As before, the lower limit comparator 102 generates a signal that is received by a timing circuit 104 which generates an appropriate signal that is received by a timing comparator 106. If this signal is less than a predetermined width for a time greater than a predetermined period of time, the comparator 106 generates an appropriate signal to activate an alarm 108. The bead width processing circuit 66 also passes through the analog base signal 92 to the statistical process control circuit 70.
The sensor alarm circuit 68 is employed to perform a sensor check to ensure that the sensor 26 is functional and free from contamination. In operation, the sensor 26 is placed over a reference bead-substrate pair of fixed and known dimensions. In response to a sensor check command, circuit 68 compares incoming ABE 51, ASE 53, and bead height analog signal 73, with pre-determined reference values for the bead-substrate pair. If the incoming ABE 51, ASE 53, and bead height analog signal 73, match the predetermined reference values for the bead-substrate pair then the sensor 26 is deemed functional and free from contamination. If not, then a sensor alarm 116 is activated indicating a sensor malfunction or contamination.
As mentioned previously, the statistical process control circuit 70 receives the analog height signal 73, the analog base signal 92 and, additionally, an external sampling signal 118. It also receives all previously mentioned alarms indicated collectively as 119. Those skilled in the art will appreciate that the statistical process control circuit 70 employs the signals 73, 92, 118 and 119 to generate and store the necessary data information for analysis by quality control personnel responsible for the operation of the dispensing system 10.
Referring now to FIG. 6, it will be appreciated that the control circuit 32 also utilizes the data generated by the bead measuring system 62 within a closed loop feedback system for the dispenser system 10. In particular, this portion of the control circuit 32 includes the bead measuring system 62 and a variable flow rate controller 120. It will be appreciated then that the control circuit 32, which is connected to the sensor 26 and the material supply 18, monitors the amplitude of the sound waves reflected from the dispensed material, the amplitude of the sound waves reflected from the substrate, and a time difference between when the amplitudes of the reflected sound waves are received by the sensor so as to control the flow of the material onto the substrate.
In particular, the sensor 26 communicates with the bead measuring system 63 which, as discussed previously, generates an analog base signal 92 and an analog height signal 73. A multiplier 122 receives both the base signal 92 and height signal 73 and multiplies them so as to generate an area signal 124. The area signal 124 is then received by a cross sectional area comparator 126 which determines the difference between a desired target cross Sectional area and the actual value of the bead material cross sectional area and generates a correction signal 128 that is received by the variable flow rate controller 120. In a similar manner, the analog base signal 92 is received by a bead base target comparator 130. The comparator 130 generates a base correction signal 132 which provides the difference between the measured base signal and the desired target value of the base signal to the variable flow rate controller 120. Finally, the analog height signal 73 is received by a bead height target comparator 134. Based upon the difference between the measured height signal 73 and the desired height target, the comparator 134 generates a height correction signal 136 that is also received by the variable flow rate controller 120.
Based upon the correction signals 128, 132 and 136 received by the variable flow rate controller 120, corresponding correction signals are sent to either the material supply 18 or to the dispenser 14 so as to adjust the shape and configuration of the material bead 22. Those skilled in the art will appreciate that the dispenser 14 could be a variable orifice gun which controls the manner in which the material is dispensed from the dispenser 14 so as to control the shape of the bead or that the variable flow rate controller 120 could control a variable speed gear pump communicative with the material supply 18 so as to control the amount of material flow onto the substrate.
Based upon the foregoing discussion of the structure and operation of the dispensing system 10, it should be apparent that the dispensing system provides numerous advantages over the prior art. In particular, the present invention provides the advantage of an on-line bead measurement and control system using a sensor that does not come in contact with the measured material. This invention allows the dispensing system 10 to automatically correct any malfunctions within the dispensing system so as to ensure the smooth operation of the assembly line. Additionally, the bead measurement and control system employed allows for an alarm system that indicates when the dispensed bead does not conform to the requirements of the assembly process. This further allows the nonconforming bead to be easily identified and reworked so as to minimize machine down time and manufacturing costs. Yet another advantage of the alarm system is that if the upper or lower bead height and base limits are only exceeded for less than a predetermined period of time, the alarms are not activated. As such, the dispensing system disclosed is sensitive enough to disregard minor inconsistencies in the shape of the bead material. It will be appreciated that the predetermined periods of time can be adjusted as required by particular dispensing applications.
A further advantage of the present dispensing system is that real time measurements can be taken of the bead height and bead base dimensions so as to provide statistical process control information to the appropriate personnel in the manufacturing facility. This allows manufacturing engineers to determine the characteristics of various materials, substrates, sensors, and dispensing devices used in the manufacturing operation.
Thus, it can be seen that the objects of the invention have been satisfied by the structure presented above. It should be apparent to those skilled in the art that the objects of the present invention could be practiced with a wide variety of materials and substrates as required.
While only the best mode and preferred embodiment of the invention has been presented and described in detail, it will be understood that the invention is not limited thereto or thereby. Accordingly, for an appreciation of the true scope and breadth of the invention, reference should be made to the following claims. | A dispensing system includes a robot that controls the positional location of a dispenser that dispenses a bead of material, such an adhesive, onto a substrate and wherein a sensor monitors the geometric configuration of the material dispensed. The dispensing system also includes a control circuit which receives information from the sensor so as to monitor geometric characteristics such as height, width and cross sectional area in such a manner that statistical process data can be gathered and also to provide alarm indications whenever the height or width of the bead do not comply with predetermined characteristics. The control circuit also provides a closed loop feedback system so that the supply of material and the nozzle can be controlled in such a manner to modify the flow of bead material whenever a discrepancy or error is detected by the control circuit. | 1 |
FIELD OF THE INVENTION
The present invention relates to a method for the production of unsaturated hydantoins. More particularly, the present invention relates to an improved method wherein the condensation of the alkyl or aryl aldehyde with a substituted or unsubstituted hydantoin is carried out in the presence of a basic salt of an inorganic acid to form the corresponding unsaturated hydantoin.
BACKGROUND OF THE INVENTION
It has long been common practice to use hydantoin and substituted hydantoins as precursors and intermediates in the synthesis of amino acids. The use of substituted hydanotins in the synthesis of amino acids such as alanine, methionine, tryptophan and lysine is well documented in the prior art. (Kirk Othmer, Encyclopedia of Chemical Technology, Volume 12, pages 694-695). The recent development of the artificial sweetner aspartame has also focused attention on the use of 5-arylidene substituted hydantoin as an intermediate in the synthesis of phenylalanine, a necessary ingredient in the synthesis of aspartame. The process for carrying out the condensation reaction of an aromatic aldehyde with hydantoin to form these 5-arylidene substituted hydantoins is also well known. (Wheeler and Hoffman, Amer. Chem. J., Volume 45, pages 368-83 (1911). A number of patents report improvements on these methods.
In U.S. Pat. No. 2,861,079, unsaturated hydantoins are produced by reacting aldehydes with hydantoin in an aqueous solution or a solution of a lower aliphatic alcohol containing an equimolar amount of a monoalkanolamine. This method has the disadvantage that, even when water is used as a solvent, large quantities of water soluble expensive amines, such as diethanolamine, are required.
In U.S. Pat. No. 4,345,072, an aromatic aldehyde substituted or unsubstituted in the aromatic nucleus is reacted with hydantoin in the presence of an equimolar amount of at least one ammonium salt of an aliphatic or aromatic carboxylic acid. A disadvantage of this method is that it requires the use of expensive carboxylic acids as solvents. Even if water is used as the solvent, this patent still requires the use of expensive ammonium salts of carboxylic acids. In addition, the process of the U.S. Pat. No. '072 requires the use of a high molar ratio of catalyst to hydantoin to achieve the desired results.
SUMMARY OF THE INVENTION
The process of the invention is characterized by the reaction of an aryl or alkyl aldehyde with a substituted or unsubstituted hydantoin in the presence of a basic salt of an inorganic acid. The process of the invention allows the use of aqueous solvents, eliminates the need for expensive amine derivatives, does not require expensive ammonium salts of carboxylic acids and can be done using a low molar ratio of catalyst to hydantoin. The process of the invention also results in substantially high yields of the desired product in a pure form.
DETAILED DESCRIPTION OF THE INVENTION
The process of the invention is particularly suited for the production of substituted unsaturated hydantoins of the general formula. ##STR1## where A is X or Y, and X is an unbranched or branched alkyl or alkenyl group, a cycloalkyl group, a cycloalkenyl group, an alkylthio group, a haloalkyl group, a haloalkenyl group, a hydroxyalkyl group, an aralkyl group, a mono- or dialkylaminoalkyl group, an acylaminoalkyl group, or a mercaptoalkyl group. Preferably the alkyl groups contain 1 to about 20, especially 1 to about 10 carbon atoms, the alkenyl group 1 to about 10, especially 1 to about 5 carbon atoms, the cycloalkyl and cycloalkenyl groups from about 3 to about 15, preferably from about 3 to about 10 carbon atoms. In a given case in the cycloalkyl or cycloalkenyl group, one or more --CH 2 -- units can also be replaced by --O--, --S--, or --NH--, or --C═ can be replaced by --N-- so that there is present the corresponding heterocyclic ring with about 3 to about 15, preferably from about 3 to about 10 ring atoms. The alkoxy, alkylthio, hydroxyalkyl, mercaptoalkyl, mono or dialkylaminoalkyl and acylaminoalkyl groups contain preferably 1 to about 10, especially 1 to about 6 carbon atoms in the alkyl or acyl groups, and ##STR2## in which Y 1 , Y 2 , and Y 3 are the same or different and can be X as defined above, hydrogen, halogen, e.g. of atomic weight 9 to 80, a hydroxy group, a nitro group, a cyano group, an amino group, an aralkyl group, or an alkaryl group. Preferably, the aralkyl and the alkaryl groups contain from about 7 to about 15 carbons in the alkylene or alkyl groups. In a given case, two of the groups Y 1 to Y 3 together can form an alkylene or alkenylene group with from about 3 to about 5 carbon atoms whereby in this case one or more --CH 2 -- units can be replaced by --O--, --S--, or --NH-- or --CH═ can be replaced by --N═.
R 1 and R 2 are the same or different and are hydrogen, alkyl, aryl, or amino.
Accordingly, there are employed aliphatic aldehydes having the formula
X--CHO
wherein X is as defined above. Non-limiting examples of suitable aldehydes include butyraldehyde, isobutyraldehyde, valeraldehyde, isovaleraldehyde, caproaldehyde, enanthaldehyde, nonaldehyde, cyclobutylaldehyde, cyclopentylaldehyde, cyclohexylaldehyde, furfural, 2-thiophenealdehyde, 2-pyrrolealdehyde, imidazolealdehyde, oxazolealdehyde, 3-indolealdehyde, pyridylaldehyde, pyrimidylaldehyde, malonic acid half aldehyde and monoaldehyde derivatives of dicarboxylic acids.
Non-limiting examples of appropriate aromatic aldehydes having the formula Y--CHO include, benzaldehyde, tolylaldehyde, 4-isopropylbenzaldehyde, 4-hydroxybenzaldehyde, 3,4,5-trimethoxybenzaldehyde, 3-bromo-4-methoxybenzaldehyde, 3,4-methylenedioxybenzaldehyde, 2-hydroxy-4-nitrobenzaldehyde, 4,5-dimethoxy-2-nitrobenzaldehyde, salicylaldehyde, vanillin, 4-phenylbenzaldehyde, 4-benzylbenzaldehyde, 4-fluorobenzaldehyde, 4-dimethylaminobenzaldehyde, 4-acetoxybenzaldehyde, 4-acetaminobenzaldehyde, 4-methylthiobenzaldehyde, and 3,5-dichloro-4-hydroxybenzaldehyde. Additional aldehydes include p-tolylaldehyde, m-tolylaldehyde, 4-chlorobenzaldehyde, 4-hexylbenzaldehyde, 2-allylbenzaldehyde, 4-allylbenzaldehyde, 2-vinylbenzaldehyde, 3-vinylbenzaldehyde, 4-methallylbenzaldehyde, 4-crotylbenzaldehyde, 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2-aminobenzaldehyde, 4-aminobenzaldehyde, 4-cyclopropylbenzaldehyde, 2-cyclopropylbenzaldehyde, 4-cyclohexylbenzaldehyde, 2,6-dichlorobenzaldehyde, anisaldehyde, 3-hydroxybenzaldehyde, 2-hydroxybenzaldehyde, 2-hydroxy-4-methylbenzaldehyde, 2-hydroxy-3-methoxybenzaldehyde, veratraldehyde, 2,4-dihydroxybenzaldehyde, 2,5-dihydroxybenzaldehyde, 4-cyclohexenylbenzaldehyde, 4-cyclooctylbenzaldehyde, 4-piperidinylbenzaldehyde, 4-pyridylbenzaldehyde, 4-furylbenzaldehyde, 4-thienylbenzaldehyde, 4-phenylethylbenzaldehyde, 4-sec.butylbenzaldehyde, 4-morpholinobenzaldehyde, 4-isopropoxybenzaldehyde, 2-propoxybenzaldehyde, 3-ethoxybenzaldehyde, 4-hexoxybenzaldehyde, 2-isopropylaminobenzaldehyde, 4-hexylaminobenzaldehyde, 4-diethylaminobenzaldehyde, 4-dipropylaminobenzaldehyde, 4-methylethylaminobenzaldehyde, 3,4-ethylenedioxybenzaldehyde, 4-acetylthiobenzaldehyde, 4-propionoxybenzaldehyde, 4-formyloxybenzaldehyde, 4-butyroxybenzaldehyde, 3,4-tetramethylenebenzaldehyde, 3,4-trimethylenebenzaldehyde, 3,4-dihydroxybenzaldehyde, alpha-napthaldehyde, beta-napthaldehyde, and 3-indenecarboxaldehyde.
In addition, hydantoins substituted at the N-1 or N-3 position can also be used in the condensation reaction. Examples of such hydantoins include, 3-methylhydantoin, 1,3-dimethylhydantoin, 1-phenylhydantoin, 3 -benzylhydantoin, 1,3-dibenzylhydantoin and the like.
The inexpensive basic salts of an inorganic acid to be employed in the reaction include ammonium bicarbonate or ammonium carbonate with the bicarbonate being the preferred compound. The basic salt can be derived from any inorganic acid with a pK a of above 5. For example, basic salts derived from carbonic acid (pK a =10.3), the bicarbonate of carbonic acid (pK a =6.4), or the monoacid phosphate of phosphoric acid (pK a =12.4) can be used.
The basic salt used is dissolved in an aqueous solvent. Other solvents include water/alcohol, or water/glycol(s). Preferably, the aldehyde is added to the solution of catalyst, solvent and hydantoin.
Generally, the condensation takes place at a temperature between about 0° to about 120° C., especially at a temperature of about 10° to about 105° C. The pressure at which the reaction is carried out is atmospheric but superatmospheric pressure can also be used.
The molar ratio of aldehyde to hydantoin can be 0.8 to 1.2. Generally, it is advantageous to employ per mole of hydantoin from about 0.85 to 1.15 moles, especially from about 0.9 to about 1.1 moles of the aldehyde.
Per mole of hydantoin, there is suitably employed an effective amount, ranging from at least 0.10 mole, preferably from about 0.20 to about 1.0 moles, especially from about 0.20 to about 0.6 moles, of the basic salt of the inorganic acid.
The reaction can be carried out on a small scale or a large scale and can be done batchwise or in a continuous fashion. If a continuous reaction is chosen, the reaction is monitored and reactants are added when depleted.
The process can comprise, consist essentially of, or consist of the steps set forth in the stated examples.
COMPARISON EXAMPLE
Similar to the procedure of U.S. Pat. No. 4,345,072, a mixture comprising hydantoin (25 g, 0.25 mole), benzaldehyde (29.3 g, 0.275 mole), ammonium acetate (19.3 g, 0.25 mole) and glacial acetic acid (60 g) were placed in a round bottom flask fitted with stirrer, condenser, thermometer and heating mantle. The white solids became yellow on heating. All the solids dissolved when the temperature reached between 120° C. and 134° C. The mixture was refluxed for one-half hour (125° to 134° C.) and then held at 120° C. for 4 hours with stirring. Solids crystallized out on cooling to room temperature. The solid was suction filtered, water washed and then ethanol washed. After air drying, the yellow orange solid had a weight of 38.0 g for an 81% yield. The melting point of the 5-benzalhydantoin obtained was determined to be 218°-220° C. which corresponds to the melting point reported in BIOCHEM J. 29, 542 (1935).
EXAMPLE 1
The Comparison Example was repeated using 25 g of hydantoin and 29.3 g of benzaldehyde but 125 ml of water was used as a solvent. 9.9 g of ammonium bicarbonate (0.125 mole, 50 mole % of hydantoin) was added with stirring over a period of 10 minutes. A considerable amount of white solid formed. The mixture was stirred at reflux for 4 hours. The reaction mixture was washed as above and 45 g of a white solid determined by UV analysis to be 5-benzalhydantoin was obtained. The theoretical yield based on starting material was 96%. The 5-benzalhydantoin had a melting point of 215°-221° C.
EXAMPLE 2
This Example illustrates that the above process of Example 1 can be adapted to a large scale process. In this variation, large quantities of raw materials were used. 1313 g of 99% pure hydantion (13.0 moles on a 100% basis), 5000 g of distilled water, 257 g of ammonium bicarbonate (3.25 moles) and 1367 g or 12.9 moles on a 100% pure basis of benzaldehyde (1395 g on an actual 98% pure basis) were used. The benzaldehyde was added to the other stirred ingredients over a period of 3 hours at 33°-98° C. with the temperature being gradually increased to the reflux temperature of 98° C. The mixture was stirred at reflux for 6 hours. The light yellow-white solid formed was filtered off and then washed twice with 1 liter of distilled water each wash and then dried on a suction filter. The product was then washed with 1.5 liter of ethanol and then dried on the suction filter. The white solid was forced air dried in an oven and had a weight of 2155 g corresponding to a yield of 89% based on benzaldehyde. The melting point was 219°-222.5° C.
Additional features of the preferred and most preferred features of the invention are found in the claims hereinafter. | Alkylidene or arylidene substituted hydantoins are produced by condensation of an aromatic or aliphatic aldehyde with hydantoin in the presence of at least one basic salt of an inorganic acid. The desired products are obtained in high yields. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention:
This invention relates to a rotary ring for spinning machinery, such as ring spinning machines, ring twisting machines, etc., particularly, a rotary ring for spinning machinery of such type that its ring-shaped rotator is turned by frictional resistance with a traveller.
2. Description of Prior Art:
As to rotary rings of this kind, there have been suggested, for example, a rotary ring of such type that a ring-shaped rotator is caused to lift by air pressure so as to realize a higher spindle speed of spinning machinery and to improve productivity and a rotary ring of such type that a ring is supported by bearings at its circumference. Additionally, FIG. 8 shows a rotary ring of a type wherein a sliding body (15) is interposed between a ring-shaped rotator (13) and a ring-shaped holder (14) and the ring-shaped rotator (13) is supported rotatably. This arrangement is set forth in Japanese Patent Application Publication Gazette No. 60-56807.
This rotary ring comprises a ring-shaped rotator having a ring-shaped flange at a top part thereof, a sliding wheel and a holder. The height of the sliding surface of a sliding part is made 1/3-3/4 of the total height of a rotary ring so as to make rotation during spinning smooth and to reduce partial lifting.
Another rotary ring type is set forth in Japanese Laid Open Patent Application Gazette No. 48-77130. This rotary ring limits the weight (W) of its rotary ring to within the scope obtained by the following formula as a function of the ring diameter (inside diameter of ring-shaped flange):
0.01050-0.40+70≧W≧0.01050-0.40+50
(W is the weight (in grams) of the rotary ring and 0 is the diameter (in millimeters of the ring).
This rotary ring, even if the spindle is turned at a speed higher than usual, involves the least frictional resistance between the rotary ring and a seating ring which supports the rotary ring. Thus, the rotary ring turns effectively and smoothly, free from vibration.
However, rotary rings of these types in which a ring rotator turns by frictional force with a traveller raise the following problem.
In the case of the rotary ring shown in FIG. 8, if the sliding area between the ring-shaped rotation (13) and the sliding body (15) normal to the thrust (or axial direction is to much larger than the sliding area between the ring-shaped rotation (13) and the sliding body (15) radial direction, the frictional torque increases and rotation of the ring-shaped rotator is impeded and contact pressure increases. On the other hand, if the sliding area normal to the thrust direction is too much smaller than the sliding area normal to the radial direction, the sliding surface normal to the thrust direction is subject to greater wear. Also, if the weight of the ring-shaped rotator is too large, frictional force between the ring-shaped rotator and the sliding body becomes large, with the result that the number of revolutions required for the ring-shaped rotator cannot be obtained and fluffing occurs frequently. On the other hand, if the weight of the ring-shaped rotator is too light, frictional force between the ring-shaped rotator and the sliding body becomes too small, with the result that when a spindle is stopped, the ring-shaped rotator does not stop but continues to turn by inertia and a traveller turns as it follows the revolution of the ring-shaped rotator. This can cause snarls of spinning yarn and end breakage at re-starting.
For the rotary ring it is general practice to lighten the weight of a ring-shaped rotator so as to increase r.p.m. of the ring-shaped rotator. For lightening the weight of the ring-shaped rotator, thickness of a trunk part of the ring-shaped rotator is reduced or its height is reduced. However, the thickness of a trunk part of the ring-shaped rotator cannot be made too thin because the relation with the ring diameter must be taken into consideration. Also, a thin trunk part is apt to warp and therefore abnormal rotation of the ring-shaped rotator occurs. If the height of the ring-shaped rotator is reduced, fluctuation to a clearance between the ring-shaped rotator and the sliding body becomes large and setting of a proper clearance is made difficult.
An object of the present invention is to stabilize and make smooth the rotation of the ring-shaped rotator. Another object of the present invention is to provide a rotary ring which stabilizes sliding of a traveller and which is free from end breakage and abnormal wear.
SUMMARY OF THE INVENTION
A rotary ring according to the present invention carries a ring-shaped rotator with a ring-shaped flange at a top part thereof, which is supported slidably by the ring-shaped supporter. In this rotary ring, the weight W (in grams) of the ring-shaped rotator and the outside diameter D 1 (in millimeters) are expressed by W/D 1 =1.5 g/mm-3.0 g/mm preferably W/D 1 =1.8 g/mm-2.8 g/mm, and in the sliding surface of the ring-shaped rotator, the height H along the axial (in millimeters) direction and the width A (in millimeters) along the radial direction are expressed by H/A=2.0-χ3.0. Also, the weight W (in grams) of the ring-shaped rotator and the inside diameter D 2 (in millimeters) ring-shaped top flange are expressed by the following relative formula,
(2 g/mm×D.sub.2 -10 g)≦W≦(3 g/mm×D.sub.2 -10 g)
where D 2 is in the range of 30-80 mm.
A ring-shaped supporter is made of synthetic resin, such as ethylene tetrafluoride, polyethylene, polystyrene, nylon, etc., having the coefficient of friction μ of 0.05≦μ<0.3.
BRIEF DESCRIPTION OF THE DRAWINGS
The nature and advantage of the present invention will be understood more clearly from the following description made with reference to the accompanying drawings, in which:
FIG. 1 is a cross section, partly broken away, of Embodiment 1;
FIG. 2 is a cross section, partly broken away, of Embodiment 2;
FIG. 3 is an explanatory drawing, showing how Embodiment 1 is used;
FIG. 4 is a drawing, showing the relation between the ratio of rotation (between r.p.m. of the ring-shaped rotator and r.p.m. of the spindle) and index number of fluffing/amount of wear of the ring-shaped supporter.
FIG. 5 is a drawing, showing the relation between the ratio of rotation (between r.p.m. of the ring-shaped rotator and r.p.m. of the spindle) and weight of ring-shaped rotator/ring diameter;
FIG. 6 is a drawing, showing the relation between the ratio (between the width of a sliding surface in thrust direction and the height of a sliding surface in radial direction) and surface pressure/inclination of the ring-shaped rotator to the ring-shaped supporter;
FIG. 7 is a drawing, showing the relation between the inside diameter of ring-shaped flange and the weight of ring-shaped rotator; and
FIG. 8 is a cross section, partly broken away, of a conventional rotary ring.
DETAILED DESCRIPTION OF THE INVENTION
A rotary ring according to the present invention has a ring-shaped rotator with a ring-shaped top flange at a top part thereof, supported slidably by a ring-shaped supporter. This ring-shaped supporter is made of synthetic resin, such as ethylene tetrafluoride, polyethylene, polystyrene, nylon, etc., and the coefficient of frictionμ between the ring-shaped rotator and the ring-shaped supporter is within the limits of 0.05≦μ<0.3.
In the case where the weight of a ring-shaped rotator is made constant, if the coefficient of frictionμ is less than 0.05, frictional force becomes small and rotation of the ring-shaped rotator increases nearly up to the spindle speed. As a result, wear of the ring-shaped supporter increases abruptly. On the other hand, if the coefficient of friction exceeds 0.3, frictional force becomes large and rotation of the ring-shaped rotator becomes too slow. As a result, fluffing occurs frequently and quality of yarn is lowered. FIG. 4 shows the relation between the ratio of rotation (between r.p.m. of the ring-shaped rotator and r.p.m. of spindle) and the fluffing of 3 mm in length/amount of wear of the ring-shaped supporter. From this figure, it has been found that in the case where the above ratio of rotation is within the limits of ##EQU1## it is proper for fluffing and amount of wear.
For obtaining the above ratio of rotation, it has been found that the ratio of the weight W (in grams) of the ring-shaped rotator to the outside diameter D 1 (in millimeters), is required to satisfy the relative formula of W/D 1 =1.5 g/mm -3.0 g/mm , preferably W/D 1 =1.7 g/mm-2.8 g/mm, as shown in FIG. 5.
With regard to the surface pressure of a sliding part of the ring-shaped rotator and its inclination to the ring-shaped supporter, we have investigated experimentally into the relation between the width A (in millimeters) of the sliding surface normal to the thrust (or axial) direction and the height H (in millimeters) of the sliding surface along the axial direction and obtained the result as shown in FIG. 6. As is obvious from FIG. 6, we have found it necessary to satisfy the relative formula of H/A=2.0˜3.0.
In the rotary ring, a clearance C of some extent is necessary between the sliding part and the ring rotator, especially in the radial direction. Due to this clearance, conventional rotary rings were not free from partial lifting. However, in the present invention in which the above range is adopted, even if the clearance of the sliding part is large, partial lifting can be prevented and the ring-shaped rotator turns smoothly. Therefore, stabilized rotation can be obtained, wear of the ring supporter at an early stage does not occur and end breakage is reduced.
Regarding the rotary ring which satisfied the above two relative formulae, the relation between the weight W (in grams) of the ring-shaped rotator and the inside diameter D 2 (in millimeters) of ring-shaped to flange should preferably be within the limits of
(2 g/mm×D.sub.2 -10 g)≦W≦(3 g/mm×D.sub.2 -10 g)
where D 2 is in the range of 30-80 mm.
which is within the optimum range shown in FIG. 7.
In the case where the weight W of the ring-shaped rotator is less than (2 g/mm×D 2 )-10 g, if the coefficient of frictionμ is constant, the frictional force becomes small and rotation of the ring-shaped rotator becomes large, causing early wear of the ring-shaped supporter. On the other hand, if the weight W of the ring-shaped rotator exceeds (3 g/mm×D 2 )-10 g, the frictional force becomes large and the ratio between the ring weight and the ring diameter (shown in FIG. 5) also becomes large. Thus, the ratio of rotation between r.p.m. of the ring rotator and r.p.m. of the spindle becomes too small, which, coupled with the increase of frictional force, causes a large increase of fluffing.
If the rotation of the ring-shaped rotator becomes too large as mentioned above, when the spindle is stopped, the ring-shaped rotator does not stop but continues to turn by inertia and a traveller turns as it follows the rotation of the ring-shaped rotator. This can cause snarling of spinning yarn and end breakage.
Embodiment 1
As shown in FIG. 1, a ring-shaped rotator 2 is made of carbon steel, alloy steel or the like and has a ring flange 1 at a top part thereof. The ring-shaped rotator 2 is 76 mm in ring (outside) diameter D 1 , 63.5 mm in ring-shaped flange inside diameter D 2 and 120 g in weight W. A ring-shaped sliding flange 2a is provided integrally at the outer circumferential part of a trunk part of the ring-shaped rotator 2. A ring-shaped supporter 3 is made of ethylene tetrafluoride resin having the coefficient of friction of 0.2μ in relation to a metal member. The ring-shaped supporter 3 is annular in shape and has at its outer circumferential part a fitting part 3a to fit a ring rail.
A rotary ring 4 is composed in such a fashion that the ring-shaped rotator 2 is supported slidably by the ring-shaped supporter 3 with a small clearance C therebetween. The rotary ring 4 is so composed that the relation of the width A (in millimeters) of a sliding surface normal to the thrust direction between the undersurface of the sliding flange 2a of the ring-shaped rotator 2 and the upper surface of the ring-shaped supporter 3 to the height H (in millimeters) of a sliding a surface normal to the radial direction between the outer circumferential part of the ring-shaped rotator 2 and the inner circumferential part of the ring-shaped supporter 3 is 2A=H.
Embodiment 2
As shown in FIG. 2, a rotary ring 6 is composed by fitting a ring-shaped fixing body 5 formed by a light weight member, such as aluminium alloy, synthetic resin or the like, in an outer circumferential part of the ring-shaped supporter 3 of the rotary ring formed similarly to Embodiment 1.
In the drawings for each embodiment, reference numeral 7 designates a retaining ring for preventing the ring-shaped rotator from slipping off the ring-shaped supporter.
How the rotary ring of the present invention is used is explained below, with reference to FIG. 3.
The ring-shaped supporter 3 of the rotary ring-shaped 4 is fitted to a ring rail 8 and is fixed by a set spring 9. Spinning yarn 11 is caught by a traveller 10 hung on the ring-shaped top flange 1 and is wound around a bobbin 12 put on a spindle.
Under the above state, if a spindle is turned, spinning yarn 11 is wound round a bobbin as it is drawn to the bobbin. At this time, the traveller slides on the ring-shaped flange 1 by winding tension T applied to yarn 11. The ring-shaped rotator 2 turns by contact pressure between the traveller 10 and the ring-shaped flange 1. This contact pressure is generally 1/2-1/3 of the centrifugal force F of the traveller.
The results of spinning tests by using the rotary ring of the present invention and the conventional rotary ring are shown in the following table.
TABLE 1__________________________________________________________________________ Concrete example Present invention Comparative exampleItem 1 2 3 1 2__________________________________________________________________________Spinning yarn Tetoron Acryl Polyester/ Acryl Tetoron/ cotton 24 Nm cotton 24 Nm cotton 45' S 6' S 45' SRing diameter mm 53 76 81 76 53Ring inside 45 63.5 70 63.5 45diameter mmNumber of 14000 8000 6850 8000 14000revolution ofspindle r.p.m.Traveller and HZ/hf CH/WZ BZ/hf OH/WZ ZS/hfits weight 5/0 NO. 7 NO. 15 NO. 7 5/0g 0.035 0.124 0.283 0.124 0.035Number of 2800 2000 1500 3000 4800revolutions ofring-shaped rotator r.p.m.Weight of ring-shaped 80 120 200 80 43rotator gCoefficient of 0.2 0.2 0.2 0.2 0.2friction betweenring-shaped rotator andring-shaped supporter μRatio between H = 2A H = 2A H = 2.5A H = A H = 1.5Awidth A and heightH of slidingsurfaceFrequency of end 3 3 3 5 6breakagePcs/400 SP/hrNumber of pieces 30 60 20 100 60of 3 mm fluff__________________________________________________________________________
As shown above in Table 1, as compared with conventional rotary rings, the rotary ring according to the present invention involved less incidence of end breakage and fluffing and thus made it possible to spin yarn of good quality.
Since the rotary ring according to the present invention is composed as mentioned above, it provides stabilized rotation. Moreover, as the ring-shaped rotator stops almost at the same time as a spindle stops, end breakage is reduced to a large extent and yarn of good quality with less fluff can be spun.
From the foregoing advantages, use of rotary rings according to the present invention makes it possible to increase the spindle speed still more and to realize high productivity of yarn. | Disclosed is a rotary ring for spinning machinery, such as ring spinning machines and ring twisting macines, which provides stabilized rotation of a ring-shaped rotator and involves no end breakage of yarn during spinning. This is accomplished by specifying the coefficient of friction μ between the ring-shaped rotator and the ring-shaped supporter, the relation between the weight W of the ring-shaped rotator and the outside diameter D 1 and ring-shaped top flange inside diameter D 2 , and the relation between the width A along the radial direction and the height H along the axial directio between the sliding surfaces of the ring-shaped rotator and the ring-shaped supporter. This rotary ring makes it possible to realize higher spindle speed and higher productivity of yarn. | 3 |
FIELD OF THE INVENTION
The present invention relates to an apparatus and method for producing a single crystal by the Czochralski technique comprising an auxiliary vacuum port, and an auxiliary vacuum pump dedicated to the machine in the event of failure of the primary vacuum pump.
BACKGROUND OF THE INVENTION
In a conventional crystal growing apparatus employing the Czochralski (CZ) technique, charge material, such as silicon, gallium-arsenide, and the like, that is to be grown into a single crystal is loaded into a crucible. A circumferential heater surrounds the crucible, and supplies heat to melt the charge material to a molten state. A seed crystal with the desired crystalline structure is then lowered into contact with the melt, and allowed to thermally stabilize. The seed is rotated one direction, and the crucible is rotated the opposite direction. The seed is then raised at a controlled rate, thus enabling growth of a crystal. Typically, crystal growth is accomplished at a pressure lower than atmospheric, with an inert purge gas supplied to flush the system of impurities.
A main controller is connected to respective control circuits for drive mechanisms, limit switches, sensors, pressure control and the like, so as to completely control the crystal pulling apparatus. For safety reasons, the supply of power to the heater is interlocked with sensors to other key items such as the vacuum pump, inert purge gas, and a cooling water system. As such, if an anomaly occurs in the vacuum system, inert purge gas system, or the like, the power supplied to the heater is shut off for safety reasons.
During a main vacuum pump failure situation, in a relatively short time the molten charge material will begin to freeze into a solid form. Such solidification of the molten charge material can cause significant damage and potential danger. It is common for the charge material to be wasted, as well as the crucible and other parts supporting the crucible due to thermal expansion. The associated costs with a failure from inoperable machine time, lost charge material, broken or damaged crucible and related parts, and time needed to clean and repair the crystal growing apparatus are significant. Moreover, an abrupt solidification of a large amount of the charge material may cause a leak of the melt, which could in turn lead to grower damage, and potentially a steam explosion or other significant safety problem.
To maintain reduced pressure, a vacuum pump is run continuously during the crystal pulling process. This main vacuum pump is subjected to substantial quantities of silicon oxide dust, a byproduct of molten silicon. In the past, oil-sealed vacuum pumps were used. However, oil-sealed pumps require a substantial amount of power, and the oil is a contaminant to the vacuum chamber.
It is now common to use a dry vacuum pump as the main vacuum pump in a crystal growing apparatus. Dry vacuum pumps use less electrical power, which lowers the cost of ownership, and they do not have oil to contaminate the process chamber. In contrast to the oil seals used in an oil-sealed pump, a dry pump relies on extremely close tolerances between its rotors and stators to provide the necessary seals within the pump. However, the extremely small gaps between the rotors and stator of a dry vacuum pump can be filled by the silicon oxide dust, resulting in increased load on the pump motor. Left unchecked, this increased load could result in overload of the motor, tripping a breaker and causing a shutdown of the crystal growing process. Thus, there has been a demand for measures to secure greater safety, and to reduce the costs associated with such an incident.
SUMMARY OF THE INVENTION
The present invention has been accomplished in view of the above-mentioned problems, and it is an object of the present invention to provide an environment for maintaining a safe, stable process state within the crystal growing apparatus upon the loss of a main vacuum pump.
The present invention provides a method of connecting the crystal growing apparatus vacuum piping normally dedicated to the main vacuum pump to the auxiliary vacuum pump instead. After the auxiliary pump has been connected, the controller for the crystal pulling apparatus is able to re-establish gas flow, pressure control, and control of the heater. This prevents the freezing of the molten charge material, damage to the crucible or other equipment, and product loss. Even though the heating state is briefly interrupted during the switch over from the primary vacuum source to the auxiliary vacuum source, no problem will arise because the thermal capacity of the molten charge material is sufficiently large.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a crystal pulling apparatus.
FIG. 2 is a schematic illustration of an embodiment of the present invention wherein the crystal pulling apparatus is operating under primary vacuum.
FIG. 3 is a schematic illustration of an embodiment of the present invention wherein the crystal pulling apparatus is operating under auxiliary vacuum.
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will now be described with reference to the drawings.
As shown in FIG. 1., a crystal pulling apparatus 10 includes a bottom chamber 12 . The bottom chamber 12 houses a quartz crucible 14 , which is supported by a vertically moveable and rotatable susceptor and shaft assembly 16 . A cylindrical heater 18 made of, for example, graphite is disposed around the susceptor 16 , and is in turn surrounded by an insulating cylinder 20 . The bottom chamber 12 also has a conduit 40 for evacuating air during start up, and process gas during crystal pulling operations utilizing the main vacuum pump (not shown).
A top chamber 24 is disposed above the bottom chamber 12 while an isolation valve 22 is disposed therebetween. The top chamber 24 provides a space for accommodating a pulled crystal. The isolation valve 22 functions to allow a vacuum tight separation between the top chamber 24 and the bottom chamber 12 thus enabling a pulled crystal to be removed from the top chamber 24 without losing vacuum or temperature in the bottom chamber 12 . The top chamber 24 has a conduit 70 that goes to the auxiliary vacuum pump (not shown) that allows the top chamber to be evacuated of air and purge gases, so it may be rejoined with bottom chamber 12 .
A winding mechanism 26 is disposed above the top chamber 24 , and includes a winding drum 28 within the winding mechanism 26 . The winding mechanism 26 is rotatable around a vertical axis with respect to the top chamber 24 . A wire 30 is wound onto the winding drum 28 , and extends downward. A seed chuck 32 for holding a crystal seed 34 is attached to the lower end of the wire 30 .
When a single crystal is to be grown in the crystal pulling apparatus 10 , the isolation valve 22 is in an open position so as to allow the seed 34 to be lowered into the bottom chamber 12 . Both the bottom chamber 12 and the top chamber 24 are evacuated, and purged with an inert gas. Subsequently, a charge material, such as silicon, is placed in the crucible 14 , and heated by the heater 18 , thereby making a material melt 36 .
The seed crystal 34 is lowered by the winding drum 28 until the end of the seed crystal 34 is lowered into the melt 36 . After allowing the seed crystal 34 to reach temperature equilibrium with the melt 36 , the winding drum 28 slowly begins to wind up the wire 30 , thus enabling a crystal 38 to be pulled. During the pulling operation, the winding mechanism 26 and thus the seed are rotating in the opposite direction of the susceptor assembly 16 .
A main controller (not shown) controls and monitors, among other things, the vacuum in the bottom chamber 12 . When vacuum failure occurs in the bottom chamber 12 , the power to the heater 18 is shut off.
Now turning to FIG. 2, exhaust gases flow from the bottom chamber through conduit 40 through a valve 42 and into the main vacuum pump 48 . In a preferred embodiment of the present invention, in the event of vacuum failure, power is shut off to the heater, and valve 42 closes to prevent backflow of exhaust gas back into the bottom chamber. In such a failure, a conduit 58 containing a very low cracking pressure check valve 54 , can be readily attached to conduit 40 through flange 52 . The opposite end of conduit 58 is then attached to conduit 70 through flange 60 , after making sure vacuum pump 68 is off, and opening cap 62 . When the conduit 58 is attached to both conduit 40 and conduit 70 , the operator can then open valve, thereby allowing the bottom chamber 12 to be evacuated by the auxiliary vacuum pump 68 , as illustrated in FIG. 3 . Purge gas flow can be re-initiated and the power to heater 18 can now be turned on, thus allowing the heater to maintain the melt 36 in a molten condition, thereby preventing freezing of the melt and damage to, for example, the crucible 14 and susceptor assembly 16 , through thermal expansion of the melt 36 .
After pressure control has been regained in the bottom chamber 12 , the failed main vacuum pump 48 can be disconnected from conduit 40 through flange 44 , and from the exhaust system (not shown) through flange 46 . The main vacuum pump 48 can now be replaced or fixed, and reinstalled. After main vacuum pump 48 has been reinstalled, power to the heater 18 is again stopped, valve 50 is closed and valve 42 is reopened. The power to the heater 18 is again supplied, and the main vacuum pump 48 now provides pressure control for the bottom chamber 12 . Vacuum pump 68 can now be shut off, and conduit 58 can now be removed, thus returning the crystal pulling apparatus to normal operating conditions. After allowing growing conditions to stabilize, crystal pulling may resume.
An alternate form of the present invention would provide permanent fixed conduit and valves to auxiliary vacuum pump 68 , with the main controller programmed such that in detection of a failed main vacuum pump 48 , all requisite valves arc actuated as described above in the manual method automatically, with a warning alarm activated to inform the operator.
Yet another alternative form of the present invention would allow for the 58 to be attached to flange 44 after the removal of primary vacuum pump 48 on one end, and attached to flange 60 of the auxiliary pump 68 , thus eliminating the need for valve 50 , flange 52 , and valve 54 .
Other embodiments of the present invention will be apparent to those skilled in the art from a consideration of this specification or practice of the invention disclosed herein. It is intended that the specification be considered in all aspects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of the equivalence of the claims are to be embraced within their scope. | A crystal pulling apparatus is disclosed which employs the Czochralski method. The crystal pulling apparatus is operated while a containing a crucible of molten material, while maintaining the growing chamber under a controlled pressure of less than atmospheric. In the event of a vacuum pump unexpectedly ceasing operation, power to the heater is terminated, thus allowing the molten material to solidify. In such an event, a second vacuum pump can readily be attached to the growing chamber thus restoring pressure control, and allowing power to the heater to be restored. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This patent application is a continuation-in-part of application Ser. No. 12/803,567, filed Jun. 29, 2010, the disclosure of which is incorporated herein by reference.
TECHNICAL FIELD
This description relates generally to a restraint device and more specifically to a device for physically restraining an individual as well as for selectively applying an electrical shock to control a combative or resistive individual or to deter or repel an attack by an individual or an animal. The device may be utilized by law enforcement personnel as well as by joggers, hikers, bicyclists, animal control officers and others.
BACKGROUND
There are various non-lethal control, defensive or restraining devices used by law enforcement and others to restrain and control detainees or to ward off an attacker. The simplest of these restraint devices are handcuffs, manacles or shackles which have been available and have been used for many years. Manacles are placed about the wrists of an individual or, in some cases, also placed about the ankles to restrict freedom of motion. While handcuffs and manacles are effective, an individual or detainee, in some instances, can free himself or herself from these devices either by disabling the lock or by manipulation in a manner to free the wrists or ankles.
More recently other devices have been developed to either restrain or temporarily incapacitate an individual. Aerosol defense sprays containing Capsicum or tear gas are well known. Stun guns use batteries to supply electricity to a circuit which includes multiple transformers which boost the voltage and reduce the amperage and which charge is stored in a capacitor. The capacitor builds up and stores the electrical charge and, upon activation, releases the charge to electrodes which is placed in contact with an individual, causing temporary interference with the individual's nervous system and muscular control to incapacitate the individual.
A variation of the stun gun is the more recently developed TASER® gun. TASER® devices work in the same basic way as stun guns, except the electrodes are positioned on the end of conductive wires attached to the electrical circuit of the TASER® device. When activated, gas pressure launches the electrodes and the attached wires. Small barbs are affixed to the electrodes so that they will attach to the individual's body or clothing. Electrical current travels through the conductive wires, stunning the individual in basically the same way as a conventional stun gun.
A main advantage of a TASER® device is that individuals can be brought under control at distances of up to 20 feet. Being able to maintain a distance or space between a detainee or would-be assailant, significantly decreases the risk to law enforcement personnel or intended victims.
While, as mentioned above, devices such as handcuffs, manacles, shackles, aerosol spray, stun guns and TASER® guns are effective in many situations, they all inherently have certain disadvantages. Accordingly, there exists a need for an effective restraint and control device which law enforcement and other individuals can use to restrain an individual while maintaining a space between the individual and law enforcement personnel. Further, there exists the need for a device of this type which can both provide physical restraint without electrical shock or in the case of more extreme resistance by a detainee, can also apply electrical shock to temporarily disable the individual. While the device has principal application to law enforcement, the device may also be used by civilians as a protective safety device in the event of an attack or threatened attack, as well as by animal control personnel.
Many of the attendant features will be more readily appreciated as the same becomes better understood by reference to the following detailed description considered in connection with the accompanying drawings.
SUMMARY
The following presents a simplified summary of the disclosure in order to provide a basic understanding to the reader. This summary is not an extensive overview of the disclosure and it does not identify key/critical elements of the example or delineate the scope of the example. Its sole purpose is to present some concepts disclosed herein in a simplified form as a prelude to the more detailed description that is presented later.
The present example provides a restraint and control device having an insulated handle at the upper or proximal end and a rod at the distal end which rod is telescopic within the handle so that the overall length of the restraint device can be adjusted. A lockable manacle or cuff is secured to the end of a tether. The manacle or cuff has a fixed arcuate section and a pivotal arm which is engageable in a lock on the fixed section to encircle the limb of an individual. The tether is a wire of stainless steel or other strong material which also serves as an electrical conductor. The end of the tether opposite the cuff is secured to a retractor within the handle. In the retracted position, the cuff is secured at the end of the telescopic rod so that the cuff and the restraint device are an integral, rigid assembly and the tether is fully retracted on to the retractor. In this position, the restraint and control device is rigid and can be attached to the limb of an individual at the cuff or manacle so the movements of the individual can be restrained and controlled by a law enforcement or other individual using the handle while still maintaining the restrained individual at a safe distance.
The tether can be released to free the cuff from the end of the rod. In this deployed position, the restrained individual will have more freedom of movement, but can still be controlled while maintained at a greater distance from the law enforcement or other individual.
The upper end of the handle of the restraint and control device houses a battery, transformer, capacitor and circuitry common to stun devices. This circuitry is connected to electrodes on the exterior of the distal end of the rod, as well as electrodes located within the cuff. A trigger, preferably within a trigger guard on the handle, can be operated to cause a high voltage, low amperage discharge to the electrodes which will deliver a disabling or stunning shock to the individual. The electrodes on the distal end of the rod will deter a detainee from attempting to grab the rod to wrestle it away from law enforcement personnel or other user.
DESCRIPTION OF THE DRAWINGS
The present description will be better understood from the following detailed description read in light of the accompanying drawings, wherein:
FIG. 1 is a partial perspective view showing the cuff on the distal end of the restraint device secured about the limb of a detainee;
FIG. 2 is a perspective view of the restraint device of the present example shown in a retracted, rigid position;
FIG. 3 is a partial perspective view showing the distal end of the restraint device of the present example secured about the limb of an individual in a position with the tether deployed;
FIG. 4 is a perspective view of the restraint device of the present example showing the telescopic extension of the rod and of the cuff from the handle;
FIG. 5 is a perspective view similar to FIG. 4 showing the distal rod end retracted and the tether and cuff deployed, the rod being provided with electrodes for applying a stun or electrical shock to a detainee;
FIG. 6 is a sectional view taken along line 6 - 6 of FIG. 4 ;
FIG. 7 is a sectional view taken along line 7 - 7 of FIG. 5 ;
FIG. 8 is a schematic diagram showing the components of the electrical circuit housed within the handle of the restraint device as shown in FIG. 5 ; and
FIG. 9 is a detail view of the handle broken away to illustrate the retractor in the handle of the device for deploying and taking up the tether.
FIG. 10 shows an alternative example of a wireless controlled restraint and control device.
FIG. 11 is a perspective view of the restraint device of the including a compound telescopic extension of the rod and of the cuff from the handle.
Like reference numerals are used to designate like parts in the accompanying drawings.
DETAILED DESCRIPTION
The detailed description provided below in connection with the appended drawings is intended as a description of the present examples and is not intended to represent the only forms in which the present example may be constructed or utilized. The description sets forth the functions of the example and the sequence of steps for constructing and operating the example. However, the same or equivalent functions and sequences may be accomplished by different examples.
The examples below describe a restraint device. Although the present examples are described and illustrated herein as being implemented in a ankle restraint system, the system described is provided as an example and not a limitation. As those skilled in the art will appreciate, the present examples are suitable for application in a variety of different types of restraint systems applicable to various extremities, and portions of those extremities.
FIG. 1 is a partial perspective view showing the cuff on the distal end of the restraint device secured about the limb of a detainee. The manacle 20 , may be secured about a limb L such as an arm or a leg. Advantageously the manacle 20 may be applied without an officer, or other user having to be in close proximity either in attaching the manacle, or after it is applied. The manacle may be made in various sizes for us with humans and animals of various sizes. Use of eh restraint and control device advantageously allows an electrical stunning device to be used without having to apply electrodes to a torso. Such electrode placement away from the torso should greatly reduce risk of heart attack in those who have had a electrical stun applied to them.
FIG. 2 is a perspective view of the restraint device of the present example shown in a retracted, rigid position. The restraint and control device of the present example is shown and is generally designated by the numeral 10 .
The restraint device 10 has an elongate, generally tubular body 12 having a handle 14 at its upper proximal end and a lower, distal end 16 . The handle 14 may be a strong, lightweight non-conductive material such as a fiberglass or a polymeric composite, or the like. The tubular shape may be round as shown, but this is not limiting as the tube could have a square, elliptical, rectangular or other shaped outline.
At an upper end of the body 12 a handle may be disposed. The upper end of the handle 14 may be contoured having recesses 18 to receive the fingers of the user. The handle 14 may also be provided with a resilient covering, both for comfort of the user and which covering is insulated to protect the user from electrical shock.
A manacle or cuff 20 is positioned at the lower end 16 of the body 12 . The manacle 20 may include a lock body 22 , preferably of the double locking type, which has internal ratchet teeth 24 operable by a key (not shown) inserted in the lock opening 26 and rotated to open the ratchet teeth 24 and release the bolt of a double locking type lock. A fixed, generally arcuate arm 30 extends from one side of the lock body and is pivotally secured to arm 32 at pivot 36 . A torsion spring 38 may be provided at pivot 36 to bias or urge the arm 32 to the open position when the arm 32 is unlocked. The distal end of arm 32 is provided with teeth 35 which are engageable with the ratchet teeth within the lock body and, in the locked position, the arm is prevented from opening and also prevented from further tightening. Handcuff locks of this type are known to those skilled in the art.
When the cuff 20 is placed about the limb of an individual, as shown in FIG. 1 , and locked, the restraint device is rigid and can be used to restrain and control the movements of an individual. The cuff 20 can be opened at key lock 26 and the arm 32 will move to the open position under the influence of the spring 38 . The user can engage the fixed arcuate section 30 about the limb of an individual and a quick, smart “snapping” wrist action will cause the locking arm 32 to be engaged in the lock so that the user does not have to bend down or come into close proximity with a restrained individual. Being able to maintain a distance from the individual to be restrained is a safety precaution and diminishes the possibility that the restrained individual can, in some manner, overcome or successfully resist restraint.
The restraint device 10 can be a unitary piece, but it may advantageously be constructed as two pieces coupled by a tether that provides additional advantages in use. In the two piece unit described herein, the manacle 20 couples to the body 12 by being shaped to fit in a receiving aperture disposed in the lower end of the body 12 . The device 10 may remain rigid during application, and afterwards, if desired separated into two coupled pieces, coupled by a tether (not shown) to allow greater mobility. Separation may be accomplished by depressing a release 95 , disposed in the body 12 .
FIG. 3 is a partial perspective view showing the distal end of the restraint device of the present example secured about the limb of an individual in a position with the tether deployed. Another feature of the present example is that the restraint allows the handle or body 12 to be loosely tethered to the restrained individual. In this way, the law enforcement officer or other user may maintain a greater distance from the detained individual, but still may maintain control of the detained individual.
A strong tether cable 80 is connected to the cuff 20 . The cable may be a stainless steel or other wire that extends through the lower tubular elongate body 12 into the upper handle. The cable may incorporate electrical conductors 70 coupled to the electrodes 50 , 50 A, and activated by the officer in alternative examples of the restraint and control device including a TASER®, or other equivalent stunning device.
Before activation the cuff 20 may be held against a flush cut end of the tube 12 , by the cable tension, as its retraction mechanism may be under spring bias. Being held against the flush cut tube by cable tension may also be augmented by other equivalent coupling mechanisms. For example a cone may be disposed on the manacle so that it retracts and centers when pulled into the hollow center of the tube 12 . Alternatively any sort of aperture may be disposed in either the manacle 20 or tube 12 to recievabally couple to a mating surface provided on the component that will mate with it.
FIG. 4 is a perspective view of the restraint device of the including a telescopic extension of the rod and of the cuff from the handle. The device may be extensible so the user may adjust the length of the body 12 . A lower rod end 16 is slidable within the tubular body 12 . The lower rod end 16 defines a longitudinally extending slot 40 in which a plurality of bores 42 are provided. A spring-loaded detent pin 46 is provided at the lower end of the handle portion which is engageable in one of the bores to lock the rod at a selected position.
FIG. 5 is a perspective view of an alternative example of the restraint and control device similar to FIG. 4 . The restraint device of the present example may also be provided with the capability of applying a high voltage, low amperage electrical charge to an individual to assist in restraining or stunning an individual who is resistive or combative.
The figure shows the distal rod end retracted and the tether and cuff deployed, and further includes the rod being provided with electrodes 50 for applying a stun or electrical shock to a detainee. To provide a shock a conventional circuit such as used in an electric fence, stun gun, or TASER® may be utilized, as in this example by including it in the body 12 .
The electrical circuit 60 is connected via at least two conductors 70 to the electrodes 50 and, upon discharge, activated by a trigger 55 on the handle will send the electrical charge to the electrodes. The conductors 70 are contained within tether 80 or the tether 80 itself may serve as the conductor between the electrical circuit and the electrodes.
Additional electrodes 50 A may also be located on the inner side of the arms of the cuff and are shown as fixed arms 30 . A safety may be provided to lock the trigger 55 and prevent inadvertent discharge. The safety is conventionally constructed like a pushbutton safety on a firearms, as is well known to those skilled in the art. Alternatively other types of trigger locks may be used as safety's including bales latches and the like. The charge delivered to the electrodes 50 A on the cuff from the circuit 60 will stun the restrained detainee. The electrodes 50 on the lower end of the body 12 of the device can be placed in contact with an unrestrained individual to subdue the individual. The electrodes 50 will also hold to fend off a restrained individual from attempting to grab the device and wrest it from law enforcement personnel or other user.
FIG. 6 is a sectional view taken along line 6 - 6 of FIG. 4 and shows the detent pin 46 in an engaged position in one of the bores 42 . The telescopic lower rod end 16 may also be adjusted by other convenient mechanisms such as an adjustable locking slip collar or the like. The body may also be non-adjustable having a fixed length either longer for law enforcement personnel or shorter for civilian use.
FIG. 7 is a sectional view taken along line 7 - 7 of FIG. 5 and shows electrodes 50 disposed on the body 12 . The body 12 can be provided with two or more pairs of electrodes 50 . However, any number of electrodes, and patterns of electrodes are contemplated, two electrodes typically being a minimum number provided.
FIG. 8 is a schematic diagram showing the components of the electrical circuit 60 that may be housed within the handle of the restraint device shown in FIG. 5 . The electrodes previously shown may be coupled to an electrical circuit 60 within the handle. The electrical is a stunning circuit, conventionally constructed and may include a battery 62 , voltage amplifier 64 and a capacitor 66 or their equivalents, which are conventional to stun guns and other devices such as TASER® devices. In addition a conventionally constructed wireless receiver and antenna 67 and associated circuitry may be included in the circuit to allow remote activation of the stunning circuit 60 .
FIG. 9 is a detail view of the handle broken away to illustrate the retractor in the handle of the device for deploying and taking up the tether. The spool can be unlocked allowing the spring-biased spool to rewind the cable to return the cuff to the position shown in FIG. 2 . The user can allow the spool to fully rewind the tether, placing the cuff in a secured position at the lower end of the body.
The upper end of the body ( 12 of FIG. 2 ) houses a spring-loaded retractor spool 90 upon which the cable 80 is wound. Spring 92 will urge the spool in a direction to wind the cable on the spool. When the law enforcement officer or other user wishes to deploy the cable, a shaft acting as a release 95 will disengage the teeth on the ratchet 98 from the teeth 96 on the spool, allowing the spring-biased spool to freely rotate to pay out or deploy cable 80 when the handle is pulled and the tether cuff engaged about the limb of an individual. Thus, the user can allow the connecting tether cable to extend to a desired length at which point the spool will be locked by ratchet teeth 98 engaging the release maintaining the cable at the desired length in a taut condition.
Tether 80 is unwound from spool 90 , which may include spring bias by biasing spring 92 . Spring bias is conventionally supplied for taking up the tether, or otherwise retracting it. A ratcheting mechanism is provided by teeth 86 on the edge of spool 90 . Spool teeth may engage with a toothed spool 98 , so that as the tether 80 is extended it is not automatically retracted. The tether may be retracted by pushing an exposed end of shaft 95 that is slidebally disposed in apertures in the handle 12 . Spring bias (not shown) may be provided to return the spool 98 to position. Other equivalent structures for deploying and retracting the tether 80 may be provided that function as described herein.
The tether 80 may have the conductors 70 disposed on it, or otherwise coupled to it, along its length so that when the tether plays off of the spool the conductors go with it. The conductors may be on the inside, or outside of the tether, or may be incorporated in the tether itself. For example with conductors on the interior the tether may be a woven tubular cable with the insulated conductors included in its core. If on the outside the conductors may be bonded or otherwise coupled to the tether. The tether may be made from any suitable conductive material like a steel braided cable, nonconductive material such as nylon cord, or a combination of materials or their equivalent.
Conductors 70 may be wound on a spool behind spool 90 , and wound in the opposite direction to the tether 80 so that they unwind into the hollow handle when the tether is extended. This maintains the high voltage connection to the electronics ( 60 of FIG. 8 ) disposed in the handle. Alternatively a contactor arrangement, with brushes or the like may couple the electrical signals from the electronics ( 60 of FIG. 8 ) to the conductors 70 that have been incorporated into the tether 80 .
Alternatively the conductors 70 may deploy separately from the tether 80 with their own deployment mechanism such as spring wire wound under tension so that the wires tend to quickly play off of a spindle upon which they are wound. Other known equivalent retractor mechanisms including a manually windable retractor spool can be used in alternative examples.
FIG. 10 shows an alternative example of a wireless controlled restraint and control device. In this example a need for conductors extending from the handle is eliminated as the electronic circuit 60 is part of the previously described cuff 20 . Electrodes 50 A are activated by the trigger 55 activating conventionally constructed transmitter electronics in the body 12 that are coupled wirelessly 1001 to an antenna and receiver electronics that are coupled to the electronic circuit 60 . Optionally electrodes 50 may be incorporated into the body, with an additional electronic circuit (not shown, but as previously described) to create a stun baton after deployment of the cuff 20 . The previously described tether release 94 may be used in this example to release the cuff 20 from the body 12 . Alternatively the tether ( 80 of FIG. 3 ) may be included to provide added control.
In another alternative example, in the case of a detachable cuff having a wireless ling as shown in FIG. 10 , two cuffs may be included in the device-one at each end, increasing it usefulness for example in riots and crowd control. Controls and circuitry are duplicated as needed to control the additional cuff.
FIG. 11 is a perspective view of the restraint device of the including a compound telescopic extension of the rod and of the cuff from the handle. The device may be extensible so the user may adjust the length of the body 12 . A lower rod end 16 is slidable within the tubular body 12 in two locations allowing quick deployment. The lower rod end 16 longitudinally extends, and the piece having the catch 46 , also moves away from the body 12 as it extends to an open position.
It will be obvious to those skilled in the art to make various changes, alterations and modifications to the example described herein. To the extent such changes, alterations and modifications do not depart from the spirit and scope of the appended claims, they are intended to be encompassed therein.
Those skilled in the art will realize that the process sequences described above may be equivalently performed in any order to achieve a desired result. Also, sub-processes may typically be omitted as desired without taking away from the overall functionality of the processes described above. | A restraint device having a tubular body with a handle at one end and a telescopic extension rod at the other end which allows the overall length of the body to be selectively adjusted. A cuff is attached to a tether at the end of the rod in a non-deployed position. The tether can be released so a law enforcement officer can loosely control a detainee. Electrical circuitry in the body is connected to electrodes on the lower end of the handle and on the cuff so a disabling charge can be delivered. The device is also useful to civilians as a protective device when jogging, walking, bicycling or the like. | 5 |
PRIOR APPLICATIONS
This is a continuation-in-part application that claims priority from U.S. patent application Ser. No. 12/933,421, filed 26 Nov. 2010 that claims priority from International Application No. PCT/SE2009/050288, filed 19 Mar. 2009 claiming priority from Swedish Patent Application No. 0800645-4, filed 20 Mar. 2008.
TECHNICAL FIELD
The present invention relates to a feed system for a continuous digester in which wood chips are cooked for the production of cellulose pulp.
BACKGROUND AND SUMMARY OF THE INVENTION
In older conventional feed systems for continuous digesters, high-pressure pocket feeders have been used as sluice feeders for pressurisation and transport of a chips slurry to the top of the digester.
The Handbook of Pulp , (Herbert Sixta, 2006) discloses this type of feeding with high-pressure pocket feeders (High Pressure Feeder) on page 381. The big advantage with this type of feed is that the flow of ships does not need to pass through pumps, but is instead transferred hydraulically. At the same time it is possible to maintain a high pressure in the transfer circulation to and from the digester without losing pressure. The system has however demonstrated some disadvantages in that the high-pressure pocket feeder is subjected to wear and must be adjusted so that the leakage flow from the high-pressure circulation to the low-pressure circulation is minimized. Another disadvantage is that during transfer, the temperature must be kept low so that bangs related to steam implosions do not occur in the transfer.
As early as 1957, U.S. Pat. No. 2,803,540 disclosed a feed system for a continuous chip digester where the chips are pumped from an impregnation vessel to a digester in which the chips are cooked in a steam atmosphere. Here, a part of the cooking liquor is charged to the pump to obtain a pumpable consistency of 10%. However, this digester was designed for small scale production of 150-300 tons pulp per day (see col. 7, r.35).
Also, U.S. Pat. No. 2,876,098 from 1959 discloses a feed system for a continuous chip digester without a high-pressure pocket feeder. Here the chips are suspended in a mixer before they are pumped with a pump to the top of the digester. The pump arrangement is provided under the digester and here the pump shaft is also fitted with a turbine in which pressurised black liquor is depressurised to reduce the required pump energy.
U.S. Pat. No. 3,303,088 from 1967 also discloses a feed system for a continuous chip digester without a high-pressure pocket feeder, where the wood chips are first steamed in a steaming vessel, followed by suspension of the chips in a vessel, whereafter the chips suspension is pumped to the top of the digester.
U.S. Pat. No. 3,586,600 from 1971 discloses another feed system for a continuous digester mainly designed for finer wood material. Here, a high-pressure pocket feeder not used either, and the wood material is fed with a pump 26 via an upstream impregnation vessel to the top of the digester.
Similar pumping of finer wood material to the top of a continuous digester is also disclosed in EP157279.
Typical for these embodiments of digester systems from the late 50's to the beginning of the 70's is that these were designed for small digester houses with a limited capacity of about 100-300 tons pulp per day.
U.S. Pat. No. 5,744,004 shows a variation of feeding wood chips into a digester where the chips mixture is fed into the digester via a series of pumps. Here, so called DISCFLO™ pumps are used. A disadvantage with this system is that this type of pump typically has a very low pump efficiency.
The previously mentioned Handbook of Pulp also discloses on page 382 an alternative pump feed of chips mixtures called TurboFeed™. Here three pumps are used in series to feed the chips mixture to the digester. This type of feed has been patented in U.S. Pat. Nos. 5,753,075, 6,106,668, 6,325,890, 6,336,993 and 6,551,462; however in many cases, U.S. Pat. No. 3,303,088 for example, has not been taken into consideration.
U.S. Pat. No. 5,753,075 relates to pumping from a steaming vessel to a processing vessel.
U.S. Pat. No. 6,106,668 relates specifically to the addition of AQ/PS during pumping.
U.S. Pat. No. 6,325,890 relates to at least two pumps in series and the arrangement of these pumps at ground level.
U.S. Pat. No. 6,336,993 relates to a detail solution where chemicals are added to dissolve metals from the wood chips and then drawing off liquor after each pump to reduce the metal content of the pumped chips.
U.S. Pat. No. 6,551,462 essentially relates to the same system already disclosed in U.S. Pat. No. 3,303,088.
A big disadvantage with the systems with multiple pumps in series is limited accessibility. If one pump breaks down, the whole digester system stops. With 3 pumps in series and a normal accessibility for each pump of 0.95, the total systems accessibility is just 0.86 (0.95*0.95*0.95=0.86).
Today's modern continuous digesters with capacities over 4000 tons pulp per day use digesters that are 50-75 meters high, where a gauge pressure of 3-8 bar is established in the top of the digester in the case of a steam phase digester, or 5-20 bar in the case of a hydraulic digester. The continuous digester systems are designed to, during the main part of operation, typically well over 80-95% of operation, run at nominal production, which makes it necessary, in regard to operational costs, for the pumps to be optimized for nominal production.
A typical digester system with a capacity of about 3000 tons with a feed system with the so called “ TurboFeed™” technology requires about 800 kW of pumping power. It is obvious that these systems must have pumps that run at an optimized efficiency close to their nominal capacity. Such a feed system requires 19,200 kWh (800*24) per 24 hours, and at a price of 50 Euro per MWh, the operational cost comes to 960 Euro per 24 hours or 336,000 Euro per year.
The systems must also be able to be operable within 50-110% of nominal production which places great demands on the feed system.
This means that a system supplier must offer pumps that are large enough to handle 4000 tons and that may also be operated within a 2000-4400 ton interval. Such a pump operated at 50% of its capacity is far from optimised, but it is necessary to at least temporarily be able to operate the pump at limited capacity in case of temporary capacity problems, for example further down the fibre line.
If this system supplier offers digester systems that can handle nominal capacities of 500-5000 tons, then pumps must be designed in a number of different pump sizes so that each individual installation can offer, from a power consumption and energy perspective, optimised transfer at nominal production. This makes the pumps very expensive, as normally a very limited series of pumps are manufactured in each size. To be able to meet demands of reasonably short delivery times, the system supplier must stock pumps in all pump sizes, which is very expensive.
The digester feed should also be able to guarantee optimal feeding to the top of the digester even if the flow in the transfer line is reduced to 50% of nominal flow.
This is difficult, because the flow rate in the transfer lines should be maintained above a critical level, as well-steamed chips have a tendency to sink against the direction of the transfer flow if the speed becomes too low.
A corrective measure that can be used at low rates, is to increase the dilution before pumping so that a lower chips concentration is established. This is however not energy efficient as it forces the feed systems to pump unnecessarily high volumes of fluid, which increases the pump energy consumption per produced unit of pulp.
Each pump has a construction point (Best Efficiency Point/“BEP”) at which the pump is intended to work. At this “BEP”, shock induced loss and frictional loss are, in the case of centrifugal pumps, at their lowest which in turn leads to that the pumps efficiency is highest at this point.
A first aim of the present invention is to provide an improved feed system for wood chips wherein optimal transfer can be achieved within a broader interval around the digesters design capacity.
Other aims of the present invention are;
improved efficiency of the feed system; improved accessibility; lower operational costs per pumped unit of chips; constant chip concentration during pumping regardless of production level; a limited range of pump sizes that can cover a broad span of the digesters production capacity; simplified maintenance; lower installation costs compared to feed systems with high-pressure pocket feeders or multiple pumps in series;
The above mentioned aims may be achieved with a feed system according to the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a first system solution for feed systems for digesters with a top separator;
FIG. 2 shows a second system solution for feed systems for digesters without a top separator;
FIGS. 3-6 show different ways of attaching pumps to an outlet in a pre-treatment vessel;
FIG. 7 shows the feed system's connection to the top of a digester without a top separator; and
FIG. 8 shows a top view of FIG. 7 ;
FIG. 9 shows a third system solution for feed systems for digesters without a top separator;
FIG. 10 shows a fourth system solution for feed systems for digesters with a top separator, and
FIG. 11 shows how the transfer lines from each pump in the systems in FIGS. 9 and 10 may be combined to form one single transfer line.
FIG. 12 shows a second alternative of how the transfer lines from each pump may be combined to form one single transfer line, and
FIG. 13 shows a third alternative of how the transfer lines from each pump may be combined to form one single transfer line.
DETAILED DESCRIPTION OF THE INVENTION
In the following detailed description, the phrase “feed system for a continuous digester” will be used. “Feed system” herein means a system that feeds wood chips from a low-pressure chips processing system, typically with a gauge pressure under 2 bar and normally atmospheric, to a digester where the chips are under high pressure, typically between 3-8 bar in the case of a steam phase digester or 5-20 bar in the case of a hydraulic digester.
The term “continuous digester” herein means either a steam phase digester or a hydraulic digester even though the preferred embodiments are exemplified with steam phase digesters.
A basic concept is that a feed system comprises at least 2 pumps in parallel, but preferably even 3, 4 or 5 pumps in parallel. It has been shown that a single pump can feed a chips suspension to a pressurised digester, and it is therefore possible to exclude conventional high-pressure pocket feeders or complicated feed systems with 2-4 pumps in series.
The pumps are arranged in a conventional way on the foundation at ground level to facilitate service.
With the above outlined solution it is possible to provide feed systems for digester production capacities from 750 to 6000 tons pulp per day, with only a few pump sizes. This is very important, as these pumps for feeding wood chips at relatively high concentration are very specific in regard to their applications, and pumps that are able to handle production capacities of 4000-6000 tons pulp per day are very large and only manufactured in very limited series of a few pumps per year. The cost for these pumps therefore becomes a crucial factor for a digester system.
The table below shows an example of how it is possible to cover a production interval of 750-6000 tons with only two pump sizes optimised for 750 and 1500 tons pulp, respectively, per day;
PUMP PROGRAM
Nominal Production
Capacity (ton per day)
750 pump
1500 pump
750
1 unit
1500
2 units
2250
1 unit
1 unit
(2250 alt)
(3 units *)
—
3000
—
2 units
(3000 alt)
(4 units *)
3750
1 unit
2 units
4500
—
3 units
(4500 alt)
(2 units *)
(2 units *)
5250
1 unit
3 units
6000
4 units
(X unit * = 1: st alternative)
This table clearly shows how it is possible, with the concept according to the present invention, to cover production capacities between 1500-6000 tons with only 2 optimised pump sizes while using a single pump installation in smaller digester systems with a capacity of 750 tons. Continuous digesters with a capacity of 750 tons are seldom used for new installations today, because batch digester systems are often more competitive for these capacities. A certain after market may exist for older digester systems with a low capacity where expensive feed systems with high-pressure pocket feeders are still used.
First Embodiment
FIG. 1 shows an embodiment of the feed system with at least 2 pumps in parallel. The chips are fed with a conveyor belt 1 to a chips buffer 2 arranged on top of an atmospheric treatment vessel 3 . In this vessel, a lowest liquid level, LIQ LEV , is established by adding an alkali impregnation liquid, preferably cooking liquor (black liquor) that has been drawn off in a strainer screen SC 2 in a subsequent digester 6 , and possibly adding white liquor and/or another alkali filtrate.
The chips are fed with normal control of the chip level CH LEV which is established above the liquid level LIQ LEV .
The remaining alkali content in the black liquor is typically between 8-20 g/l. The amount of black liquor and other alkali liquids that are added to the treatment vessel 3 is regulated with a level transmitter 20 that controls at least one of the flow valves in lines 40 / 41 . With this alkali impregnation liquor the wood acidity in the chips may be neutralised and impregnated with sulphide rich (HS − ) fluid. Spent impregnation liquor, with a remaining alkali content of about 2-5 g/l, preferably 5-8 g/l, is drawn off from the treatment vessel 3 via the withdrawal strainer SC 3 and sent to recovery REC. If necessary, white liquor WL may also be added to the vessel 3 , for example as shown in the figure, to line 41 . The actual remaining alkali content depends on the type of wood used, hardwood or softwood, and which alkali profile that is to be established in the digester.
In the case where a raw wood material that is easy to impregnate and neutralise is used, for example raw wood material such as pin chips or wood chips with very thin dimensions and a quick impregnation time, vessel 3 may in extreme cases be a simple spout with a diameter essentially corresponding to the bucket formed outlet 10 in the bottom of the vessel. Required retention time in the vessel is determined by the time it takes for the wood to become so well impregnated that it sinks in a free cooking liquor.
After the chips have been processed in vessel 3 they are fed out from the bottom of the vessel where also a conventional bottom scraper 4 is arranged, driven by a motor M 1 .
According to the invention, the chips are fed to the digester via at least 2 pumps 12 a , 12 b in parallel, and these pumps are connected to a bucket formed outlet 10 in the bottom of the vessel. The bucket formed outlet 10 has an upper inlet, a cylindrical mantle surface, and a bottom. The pumps are connected to the cylindrical mantle surface.
To facilitate pumping of the chips mixture, the chips are suspended in a vessel 3 to create a chips suspension, in which vessel is arranged a fluid supply via lines 40 / 41 , controlled by a level transmitter 20 which establishes a liquid level LIQ LEV in the vessel, and above the pump level by at least 10 meters, and preferably at least 15 meters and even more preferably at least 20 meters. Hereby a high static pressure is established in the inlet to pumps 12 a and 12 b so that one single pump can pressurise and transfer the chips suspension to the top of the digester without cavitation of the pump. The top of the digester is typically arranged at least 50 meters above the level of the pump, usually 60-75 meters above the level of the pump while a pressure of 5-10 bar is established in the top of the digester.
To further facilitate the feeding to the pumps, a stirrer 11 is arranged in the bucket formed outlet. The stirrer 11 is preferably arranged on the same shaft as the bottom scraper and driven by the motor M 1 . The stirrer has at least 2 scraping arms that sweep over the pump outlets arranged in the bucket formed outlet's mantle surface. Preferably a dilution is arranged in the bucket formed outlet, which may be accomplished by dilution outlets (not shown) connected to the upper edge of the mantle surface.
FIGS. 3-6 show how a number of pumps 12 a - 12 d may be connected to the outlet's cylindrical mantle surface and how the stirrer 11 may be fitted with up to 4 scraping arms. The pumps may preferably be arranged symmetrically around the outlets cylindrical mantle surface with a distribution in the horizontal plane of 90° between each outlet if there are 4 pump connections (120° if there are 3 pump connections and 180° if there are 2 pump connections). This way it is possible to avoid an uneven distribution of the load on the bottom of the vessel and its foundation. In practice, shut-off valves (not shown) are also arranged between the outlet's 10 mantle surface and the pump inlet and a valve directly after the pump to make it possible to shut off the flow through one pump if this pump is to be replaced during continued operation of the remaining pumps.
In FIG. 1 the chips are fed by pumps 12 a , 12 b via transfer lines 13 a , 13 b (only two shown in FIG. 1 ) to the top of the digester 6 . FIG. 1 shows a conventional top separator 51 arranged in the top of the digester. The transfer lines 13 a , 13 b , preferably 2, both open into the bottom of the top separator, where, driven by motor M 3 , a feeding screw 52 drives the chips slurry up under a dewatering process against the top separators withdrawal strainer SC 1 . Drained chips will then be fed out from the upper outlet of the separator in a conventional way and fall down into the digester. In the case a hydraulic digester is used, the top separator is turned up-side down, and feeds the chips down into the digester.
The drained liquid from the top separator 51 is led through a line 40 back to the processing vessel 3 , and may preferably be added to the bottom of the processing vessel, to there facilitate feeding out under dilution.
Alternatively, line 40 may be connected to the position for the outlet of line 41 in the processing vessel 3 and line 41 may be connected to the position for the outlet of line 40 in the processing vessel 3 , according to the concept CrossCirc™. In a variation, the flow of line 40 and 41 may be mixed at the intersection of lines 40 and 41 in FIG. 1 .
The digester 6 may be fitted with a number of digester circulations and the addition of white liquor to the top of the digester or to the digester's supply flows (not shown). The figure shows a withdrawal of cooking liquor via strainer SC 2 . The cooking liquor drawn off from strainer SC 2 is known as black liquor and may have a somewhat higher content of remaining alkali than black liquor that is normally sent directly to recovery and normally drawn off further down in the digester. The cooked chips P are then fed out from the bottom of the digester with the help of a conventional bottom scraper 7 and the cooking pressure.
Second Embodiment FIG. 2 shows an alternative embodiment which does not include a top separator. Instead the transfer lines 13 a , 13 b (only two are shown in FIG. 1 ) open directly into the top of the digester. Excess liquid is then drawn off with a digester strainer SC 1 arranged in the digester wall. FIGS. 7 and 8 show this in more detail. The remaining parts of this embodiment correspond to the digester system shown in FIG. 1 .
FIG. 8 shows how 4 transfer lines 13 a , 13 b , 13 c and 13 d may open directly into the top of the digester. These outlets may preferably be arranged symmetrically in the top of the digester with a distribution in the horizontal plane of 90° between each outlet if there are 4 outlets (120° if there are 3 outlets and 180° if there are 2 outlets). The outlets are suitably arranged at a distance of 60-80% of the digester radius. FIG. 7 shows how the transfer lines 13 a , 13 b and 13 c open directly down into the top of the digester and thereby distribute the chips over the cross section of the digester. In this case a steam phase digester is shown where steam ST and/or pressurised air P AIR is added to the top of the digester, in which a chips level CH LEV is established above the liquid level LIQ LEV in the top of the digester. Excess liquid is drawn off with a strainer SC 2 and collected in a withdrawal space 51 before being led back via line 41 .
An advantage with the second embodiment, but also with the first embodiment, is that each pump may closed independently while the remaining pumps may continue pumping at optimal efficiency and without requiring modification of the feed system itself.
Third Embodiment
FIG. 9 shows an alternative embodiment for the feed system to a continuous digester without a top separator where each pump 12 a , 12 b pumps the chips suspension through a first section 13 a , 13 b of a transfer line to the top of the digester, and the first sections of the transfer lines from at least 2 pumps are combined at a merging point 16 to form a combined second section 13 ab of the transfer line before this second section is led towards the top of the digester. To maintain a constant flow rate, a supply line 15 is also connected to the merging point 16 . In this embodiment black liquor is taken from line 41 and may be pressurised with a pump 14 . However, because the black liquor has already reached a full digester pressure, the need to pressurise the liquor is limited. All other characterizing parts of the system correspond to the system shown in FIG. 2 .
Fourth Embodiment
FIG. 10 shows an alternative embodiment for the feed system to a continuous digester with a top separator where each pump 12 a , 12 b pumps the chips suspension through a first section 13 a , 13 b of a transfer line to the top of the digester, and the first sections of the transfer lines from at least 2 pumps are combined at a merging point 16 to form a combined second section 13 ab of the transfer line before this second section is led towards the top of the digester. To maintain a constant flow rate, a supply line 15 is also connected to the merging point 16 . In this embodiment black liquor is taken from line 40 and may be pressurised with a pump 14 . However, because the black liquor has already reached a full digester pressure, the need to pressurise the liquor is limited.
All other characterizing parts of the system correspond to the system shown in FIG. 1 .
FIG. 11 shows an example of how supply lines 15 a , 15 b that are used in both the third and the fourth embodiment may be connected to merging points 16 ′ in the case 4 pumps 12 a - 12 d are used. An advantage with this supply arrangement is that it is possible to guarantee optimal speed in the combined flow in the second section 13 ac/ 13 bd and in the combined flow in the final third section 13 abcd of the transfer line.
It is critical that the rate of the flow up to the digester is well over 1.5-2 m/s so that the chips in the flow do not sink down towards the feed flow and cause plugging of the transfer line. The flow in the transfer line should suitably be maintained between 4-7 m/s to make sure that the chips are transferred to the top of the digester.
If, for example, pump 12 a would be shut down due to repair or a desired capacity reduction, the flow in addition line 15 a may be increased so that the flow rate in the second section 13 ac is maintained.
In these combined line systems for transferring chips suspensions it is advantageous that the lines after the merging points 16 , 16 ′, 16 ″ have a flow cross section that is equal to or greater than the sum of the incoming lines, to avoid pressure loss in the transfer lines. Suitable equations for flow areas A may be:
A 13bd ≧( A 13d +A 13b ), and
A 13abcd ≧( A 13bd +A 13ac ).
In a transfer line where the first section has a diameter of for example 100 mm and an established flow rate of 5 m/s, a flow rate of 4.4 m/s is established if a second section that combines 2 lines with diameter 100 mm has a diameter of 150 mm. With a subsequent combination of 2 such lines with a diameter of 150 mm to a third section with a diameter of 250 mm, a flow rate of 3.18 m/s may be established. All these flow rates have a margin towards the critical lowest flow rate.
The supply lines 15 a , 15 b may also have connections directly after each pump outlet, so that the line between pump and merging point is kept flushed during the time that the pump is shut down or operated at a reduced capacity. The addition of extra fluid may also be combined with a further dilution of the chips suspension before the pumps, for example on the suction side of the pumps or in the bottom of vessel 3 .
FIG. 12 shows a cross-sectional view of a second embodiment of how lines 13 a - 13 d from the pumps may be combined to form one single transfer line 13 abcd . Here, the supply line 15 for dilution liquid provides a vertical part of the transfer line towards the top of the digester, and each line 13 a , 13 b , 13 c , 13 d from each pump is connected successively, one by one, to this vertical part of the transfer line at different heights. At each supply position, the chip flow is added in a conical part of a diameter increase in the transfer line. As is indicated by the dashed alternatives 13 b ALT / 13 d ALT , the connections from the pumps may instead be shifted from side to side on the transfer line.
FIG. 13 shows a cross-sectional view of a third embodiment of how lines 13 a - 13 d from the pumps may be combined to form one single transfer line 13 abcd. Here, the supply line 15 for dilution liquid provides a vertical part of the transfer line towards the top of the digester, and each line 13 a , 13 b , 13 c , 13 d from each pump is connected at the same height to this vertical part of the transfer line. Preferably the supply position for the chip flow is arranged in a conical part of a diameter increase in the transfer line and each connected line is oriented upwards and inclined at an angle in relation to the vertical orientation in the interval 20-70 degrees. The Figure shows only the connections 13 a , 13 b , 13 c, as connection 13 d is in the part that is cut away in this view.
The invention is not limited to the above mentioned embodiments. More variations are possible within the scope of the following claims. In the embodiments shown in FIGS. 2 and 9 , in some applications the strainer SC 1 and the return line 40 may for example be omitted, preferable for cooking of wood material with a higher bulk density, such as hardwood (HW), that for a corresponding production volume require less liquid during transfer.
In the case where a raw wood material that is easy to impregnate and neutralise is used, for example raw wood material such as pin chips or wood chips with very thin dimensions and a quick impregnation time, vessel 3 may in extreme cases be a simple spout with a diameter essentially corresponding to the bucket formed outlet 10 in the bottom of the vessel.
If the chips fed into the vessel 3 are already well steamed, the liquid level LIQ LEV may be established above a chips level CH LEV .
In the embodiments shown, an alkali pre-treatment was used in vessel 3 , but it is also possible to use a process where this pre-treatment comprises acid pre-hydrolysis.
There is a substantial difference between pumping chips suspensions/slurries compared to pumping water-like liquids. In general, handbooks in pumping provide advice and instructions for pumping water-like fluids. However, the special circumstances of pumping slurries with a high content of solid matter must always be given special attention.
One difference, when pumping chip slurries, is that chips suspensions establish a volume of interlocked chips that create a flow-restriction, or a pressure drop through the chips, of the free liquid in the chips suspension/slurry through the slurrying vessel. It cannot, therefore, be assumed that a liquid head has the same impact upon the pumping inlets as in any general application where pumps are pumping pure liquid and the hydraulic system/volume transmits a full hydraulic pressure as a result of the liquid volume disposed above the pump inlets.
Another difference is that the chips in the chips suspension interlock, or have a tendency to interlock, to one another that creates a unitary interlocked volume of chips that moves as one “plug” flow. This unitary flow does not behave like a conventional liquid-like liquids do. It is difficult to break up the unitary plug-flow of interlocked chips into several partial flows which would require that the chip-plug flow behaves more like a liquid feeding each pump inlet with equal feeding volume tapped off from the chip plug flow.
When a hot liquid is added to a flow of chips suspension containing interlocked chips, such as adding hot black liquor via a pipe, it was surprisingly discovered that the hot liquid does not mix well or thoroughly with the chips suspension because hot streaks of black liquor was discovered in the transfer lines all the way up to the digester. It was also surprisingly discovered that the hot streaks of black liquor do not shift from one side to another inside the transfer line either but remained stable in the same position inside the transfer line.
It was also surprisingly discovered that by breaking up the chips plug, by using scraping arms of a stirrer close to the outlets at the pump inlets, the interlocking effect between chips in the chips suspension is sufficiently broken-up by continuous agitation from the stirrer so the feed of the chips slurry is unrestricted towards all the pump inlets which is important when many pump inlets are used because the distribution of the flow to the various pump inlets is more even. The breaking up of the interlocked chips also enhances the mixing of the hot liquor into the chips suspension which in turn reduces the hot streaks described above.
More particularly, the breaking up of the interlocked chips positively affects the pumping of the chips slurry from the multiple outlets of the vessel up to the top of the digester even if only one single pump per transfer line is used for the entire pump head. If the plug flows are not broken up, there is a high risk of pump cavitation due to the interlocking of the chips in each pump inlet and uneven flow between the pump inlets, as all multiple pump inlets establish a negative pressure in the pump inlets and hence into the bottom of the tower increasing the risk for cavitation in pumps.
In other words, when the chips in the chips slurry are interlocked, the static pressure at the bottom of the vessel does not generally change as linearly as it does in hydraulic systems by raising the liquid level as the liquid head experiences a pressure drop through the interlocked chip pile. Especially, if multiple single pumps, i.e. one single pump per transfer line, wherein the pumps are in parallel, are connected to the bottom of the vessel, all pumps induce a super-imposed negative pressure from each pump inlet that may cause cavitation.
However, it was surprisingly discovered that the static pressure created, while the stirrer breaks up the interlocked chip plug in the chips suspension at the bottom of the vessel, is high enough so that a single pump per transfer line can pump the chips slurry to the top of the digester kept at full digester pressure without cavitation of the pump (due to lack of sufficient or uneven feed of the chips slurry to each pump inlet). The breaking up of the interlocked chips makes the flow characteristics of the chips suspension to be more similar to that of the flow characteristics of conventional or water-like liquids.
While the present invention has been described in accordance with preferred compositions and embodiments, it is to be understood that certain substitutions and alterations may be made thereto without departing from the spirit and scope of the following claims. | The feed system is for a continuous digester where at least two pumps are arranged in parallel at the bottom of a pre-treatment vessel and a stirrer is provided in direct connection to inlets to pumps. The system makes it possible to provide a feed system with an improved accessibility and operational reliability, and to operate the main part of the pumps at optimal efficiency even if the production capacity is reduced. | 3 |
BACKGROUND OF THE INVENTION
The invention relates to intersomatic spine implants.
Document FR-2 727 003 discloses an intersomatic spine implant for putting into the place of a vertebral disk after it has been removed, and comprising a body having two plane faces that come into contact with the adjacent vertebral bodies. It has two housings for receiving anchoring screws, disposed in such a manner that the screws project from respective contact faces so as to be anchored into the adjacent vertebral bodies. Each screw slopes relative to the associated contact face because the head of the screw projects from a side of the body so as to be capable of being driven once the implant has been received between the vertebral bodies. Nevertheless, it is difficult to put the screws into place because of the slope of their axes. Furthermore, the positioning of the screws cannot be improved in order to optimize the quality of the anchoring they provide without making them less accessible.
U.S. Pat. No. 5,702,391 discloses an intersomatic implant comprising a body, slidably movable pins in the body for projecting from outside faces of the body, and spherical cams slidably movable in an axial duct of the body. An actuator piece disposed at the mouth of the duct enables thrust to be applied to the cams which move the pins by a ramp effect so that they project and thus anchor the implant in the plates of the associated vertebrae. Such an implant makes it much easier to achieve robust anchoring between the vertebrae. However, the implant is very difficult to remove should that be necessary, which in contrast is not the case with the implant disclosed in above-mentioned FR-2 727 003 since it needs only to have the screws undone to eliminate anchoring between the implant and the plates.
SUMMARY OF THE INVENTION
An object of the invention is to provide an implant that is easy to install and remove.
To achieve this object, the invention provides an intersomatic spine implant comprising a body, at least one anchoring element movable relative to the body to project from a contact face of the body making contact with a vertebra, and at least one cam slidable relative to the body and suitable for displacing the anchoring element relative to the body by the effect of a ramp engaging the anchoring element, wherein the cam and the anchoring element are arranged so that the cam moves the anchoring element in two opposite displacement directions.
Thus, the anchoring element is moved by means of the cam, by taking action on the cam. Since action is no longer taken directly on the anchoring element, constraints associated with accessibility of the anchoring element are to a very large extent eliminated. As a result, the anchoring element is easier to drive into place during surgery. Furthermore, since it is no longer necessary to make the anchoring element directly accessible, its positioning can be modified in a very wide variety of ways so as to ensure that it performs its anchoring function as well as possible. Consequently, the operation of installing the anchoring element is made easier, while also making it possible to improve the quality of anchoring.
In addition, since the action of the cam is reversible, it enables the or each anchor element to be actuated so as to go from the extended position to the retracted position. It is then easy to remove the implant. This action of the cam on the anchoring element is positive in the sense that the cam entrains the anchoring element. The action of the cam does not consist solely in leaving the way open for the implant to be capable of penetrating into the body under the effect of external pressure exerted on the anchoring element by the material of the vertebrae. Thus, in particular, it is possible to remove the implant a long time after it has been put into place.
The implant of the invention may also present one or more of the following characteristics:
the cam has a thread suitable for co-operating by screw engagement with an actuator for driving the cam from outside the body;
the actuator is suitable for being mounted to move
in rotation relative to the body;
the cam is mounted to move sliding relative to the body;
the cam has an end providing a face that is undercut relative to a travel direction of the cam so as to enable the cam to be extracted from the body;
the implant includes at least two anchoring elements and at least two cams suitable for moving respective anchoring elements;
the two cams are arranged so that their threads cooperate with a common actuator;
the anchoring element slopes relative to a general plane of the contact face;
the implant includes at least two anchoring elements suitable for projecting from the same contact face;
the implant includes at least four anchoring elements suitable for projecting from the same contact face and disposed in two rows defining mutually-parallel alignment directions;
the body has two contact faces for making contact with respective vertebrae and at least one recess extending between the contact faces;
the portion of the anchoring element suitable for projecting from the contact face has faces that are undercut relative to the sliding direction of the element towards the vertebra; and
the implant presents at least two anchoring elements and an element-carrier rigidly connected to the anchoring elements.
BRIEF DESCRIPTION OF THE DRAWINGS
Other characteristics and advantages of the invention appear further from the following description of five preferred embodiments given as non-limiting examples. In the accompanying drawings:
FIGS. 1 and 2 are two perspective views of an implant constituting a first embodiment of the invention shown respectively in the assembled state and in an exploded state;
FIGS. 3 and 4 are two section views of the FIG. 1 implant during two respective steps of installation thereof;
FIG. 5 is a view analogous to FIG. 4 showing the implant between two vertebrae;
FIGS. 6 and 7 are respectively an exploded perspective view and a section view of an implant constituting a second embodiment of the invention;
FIG. 8 is a perspective view of an implant constituting a third embodiment of the invention;
FIG. 9 is a perspective view of the FIG. 8 implant with the top portion of its body removed;
FIGS. 10 and 11 are perspective views showing an implant constituting a fourth embodiment of the invention respectively in the assembled state and in an exploded state;
FIG. 12 is a fragmentary axial section view of the cam and the screw of FIG. 11;
FIG. 13 is a perspective of an implant showing a fifth embodiment of the invention;
FIG. 14 is a section view of the implant on plane XIV—XIV of FIG. 13;
FIGS. 15 and 16 are two perspective views of the cam and the element-carrier of the FIG. 13 implant shown respectively in an element-retracted position and an element-extended position; and
FIG. 17 is a section view of the cam and the element-carriers on the midplane XVII—XVII FIG. 16 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first embodiment of the implant is described with reference to FIGS. 1 to 5 . The implant 102 comprises a body 4 that is generally in the form of a rectangular parallelepiped flattened in one direction so as to define two large faces 6 , namely a top face and a bottom face, and four side faces 8 . The edges and the corners of the body are rounded to avoid injuring the tissues of the human body for which the implant is intended. The top and bottom faces 6 are generally plane in shape and they have respective transverse profiles that are sawtoothed or zigzag, the tips of the teeth defining continuous mutually-parallel edges. These edges provide good engagement of the top and bottom faces 6 against the plates of the vertebral bodies of the destination vertebrae 9 , as shown in FIG. 5 .
The body 4 has two through recesses 10 extending close to two opposite edges of the body and between the top and bottom faces 6 so as to open out into both of them. Furthermore, each side face 8 has an orifice 12 opening out into one of the recesses 10 halfway between the top and bottom faces 6 . When the implant is put into place, the recesses 10 are filled with graft tissue which can thus grow towards the vertebral plates through the recesses 10 and the orifices 12 .
The body 4 has a cylindrical duct 14 so that its axis 16 extends through two opposite corners of the body that are remote from the recesses 10 , and parallel to the general planes of the top and bottom faces 6 . The duct 14 is open at both ends. In the vicinity of a distal one of its ends, it presents a segment 18 of smaller diameter that is threaded. The remainder of the duct 14 constitutes a smooth segment 20 of larger diameter than the segment 18 .
The body 4 has channels 22 of cylindrical shape extending from the segment 20 to the top and bottom faces 6 . All of the channels 22 have axes 24 which intersect the axis 16 in the segment 20 , in this case at right angles. There are twelve such channels 22 in this case. They are subdivided into two groups of six channels 22 . In each group, the six channels 22 are parallel to one another, in axial alignment in pairs, and situated in a common plane that includes the axis 16 . The section of FIGS. 3 and 4 lies in one such plane so that all six channels in one of the groups can be seen in these figures. This plane slopes relative to the general planes of the top and bottom faces 6 such that the axes 24 of the channels 22 slope likewise. The slopes are symmetrical and have the same angle for both groups of channels. In each group of six channels 22 , three of the channels open out into the top face 6 and three into the bottom face 6 . Each channel 22 that opens out into the top face 6 is in axial alignment with one of the channels in the same group that opens out into the bottom face. In each group, the three channels that open out into the same face are spaced apart a common pitch. Thus, in each face 6 , channels 22 open out that are distributed in two rows defining mutually-parallel alignment directions, with the channels in each row sloping in opposite directions.
Each channel 22 slidably receives an anchoring element constituted in this case by a pin 26 having a smooth cylindrical body presenting a point at an end closer to the face 6 and presenting, at an opposite end, a head having a convex spherical face of radius greater than the radius of the channel 22 and of width greater than the diameter of the associated channel 22 . The head is situated in the segment 20 and thus holds the pin 26 prisoner against being extended fully through the associated face 6 .
The implant has a cam 130 that is circularly cylindrical about an axis lying on the axis 16 . At a distal axial end it presents a threaded cylindrical face 134 suitable for entering into screw engagement with the segment 18 of the body. At a proximal axial end 136 it presents a head of diameter greater than the diameter of the segment 20 of the body so as to come into abutment against the outside of the body. The head presents a socket, e.g. a hexagonal socket with six flats, thus enabling the cam 130 to be rotated about its axis by means of a suitable tool such as a key.
Between its two ends, the cam 130 presents three broad cylindrical faces 138 , three cylindrical faces 140 that are narrow compared with the broad faces 138 , and three frustoconical faces 142 that slope towards the threaded distal end 134 . These faces alternate and are distributed in three consecutive groups each comprising in the proximal-distal direction: a broad face 138 ; a frustoconical face 142 ; and a narrow face 140 , the frustoconical face 142 providing a transition in level between the other two faces. The lengths of the faces along the axis 16 are identical for each type of face. These lengths are adapted so that when the threaded distal end 134 of the cam engages with only the proximal end of the segment 18 , as shown in FIG. 3, the heads of the pins 26 bear against the narrow faces 140 , with each narrow face 140 being in contact with the heads of four pins 26 whose axes 24 are coplanar in a plane perpendicular to the axis 16 , whereas when the head of the cam 130 is in abutment against the body, as shown in FIG. 4, the heads of the pins 26 bear against the broad faces 138 , with each broad face 138 being in contact with the four above-mentioned pins 26 . The diameter of the narrow faces 140 is such that when in the position shown in FIG. 3, referred to below as the “retracted position”, the points of the pins 26 do not project beyond the associated face 6 , or project so little that they do not significantly impede installation of the implant 102 between the vertebral bodies. The diameter of the broad faces 138 is such that when in the position of FIG. 4, referred to below as the “extended position”, the pins 26 project from the face 6 , e.g. by one-fourth to one-third of their length, and penetrate far enough into the associated vertebral body to prevent the implant being withdrawn.
The implant is put into place as follows. After a vertebral disk has been removed, and after the recesses 10 have been filled with graft tissue, as mentioned above, the implant 102 is inserted between the vertebral bodies of the vertebrae 9 associated with the disk that has been removed. The height of the body 4 of the implant corresponds to the thickness of the removed disk. The implant is inserted in such a manner that the threaded segment 18 is substantially in the posterior position. The faces 6 extend facing respective vertebral plates, being parallel thereto and in contact therewith. The implant is inserted while it is in its retracted configuration as shown in FIG. 3 .
Once the implant is in position, a key is used to drive the head of the cam 130 which is situated in the anterior position so as to cause the cam to turn about its axis 16 . Given the screw engagement between the distal end 134 of the cam and the segment 18 , the cam thus follows a helical path along its axis 16 . For each group of four pins, the contiguous frustoconical face 142 comes progressively into contact with the heads of the pins and constitutes a ramp which, given its displacement towards the segment 18 , urges the four pins so as to cause them to slide towards the outside of the body. As the pins 26 extend outwards, they penetrate into the vertebral plates and anchor the implant in the vertebrae. The four pins 26 then come to bear against the contiguous broad face 138 and project from the respective faces 6 in the extended configuration. At the end of driving the cam 130 , the head of the cam bears against the body and the distal end 134 of the cam is at the distal end of the segment 18 .
In a variant of this first embodiment, the screw engagement between the cam 130 and the body 4 could be replaced by snap-fastening or clipping to prevent the cam from moving relative to the body after the cam has merely been thrust parallel to its axis. The cam is then slidably movable relative to the body. Under such circumstances, its cross-section relative to its axis need not be circular, for example it could be rectangular.
A second embodiment of the implant is described with reference to FIGS. 6 and 7. Elements that differ from those of the first embodiment are given numerical references plus 100 .
In the implant 202 , the body 4 has substantially the same configuration as in the preceding embodiment, apart from the fact that the smooth larger-diameter segment 20 constitutes the entire length of the cam duct 14 . In this case, the cam 130 is replaced by a set of three cams 230 and a screw 250 . The screw 250 has a drive head 236 forming an abutment against the body, analogous to that of the cam 130 . The screw has a threaded rod 252 .
The three cams 230 are identical to one another. Each cam 230 is generally cylindrical in shape. It has a threaded cylindrical duct 253 suitable for co-operating with the rod 252 by screw engagement. Each cam 230 has four slots 254 each associated with a respective specific one of four pins 26 to be actuated by the cam. Each slot 254 extends in a plane that is radial relative to the axis 16 of the cam. Each slot 254 has a shallow, high portion 238 , a low portion 240 which is deep relative to the shallow portion, and an intermediate portion 242 forming a transition in level between the high and low portions. The high portions of the four slots 254 in any one cam are contiguous to the proximal end of the cam. Perpendicularly to the axis 16 , each slot has a profile in the form of an outwardly open circular arc extending over more than a semicircle, of radius that is constant along the slot, with the edges of the circular arc extending outwards level with the intermediate and low portions in the form of two mutually-parallel plane flanks. Each slot is adapted to receive the head of the associated pin 26 in the axial direction via either end, while preventing the head from escaping in the radial direction of the cam. The bottom of each slot 254 constitutes a first ramp for causing the associated pin 26 to slide outwards when the cam slides towards the distal end of the duct 14 . An advantage of this embodiment is that it is reversible. Since the head of each pin 26 is held captive in the associated slot 254 , the edges of the slot constitute a second ramp enabling the pin to be moved back into the retracted position when the cam 254 slides towards the proximal end of the duct.
The various parts of the implant are assembled as follows. After the pins 26 have been received in their channels 22 in the body 4 , one of the cams 230 is slid to the central position associated with the pins 26 in the middle of the row. To be able to do this, the cam 230 must be capable of “getting past” the four pins 26 at one of the ends of the rows, e.g. the four pins 26 at the distal end if the cam is inserted via said end. This step is performed by inserting the cam 232 in the distal end of the duct 14 and inserting the pins 26 into respective slots 254 . Since the pins 26 are initially projecting, continued thrust of the cam towards the center of the duct has the effect, given the ramps in the slots, of moving the pins 26 into the retracted configuration. As the cam continues to be thrust in, the distal ends of the pins leave the low portions 240 of the slots. Applying continued thrust to the cams serves to insert the pins in the centers of the rows into the high portions 238 of the slots 254 and finally to bring them into the low portions 240 of the cam. Thereafter, the cam 230 for occupying the distal position is inserted in the same manner. After that the cam 230 for occupying the proximal position is inserted in the same manner via the proximal end. Once all of the pins 26 are in the low portions 240 of the slots, in the retracted configuration, the screw 250 is screwed into the cam 230 so as to be in screw engagement therewith.
Once the implant has been installed between the vertebrae, the screw 250 is pushed towards the distal end of the duct 14 , thereby causing the cams 230 to slide in the same direction. By means of the ramps at the bottoms of the slots 254 , the pins are then caused to slide along their respective channels so as to move from the low portions 240 to the high portions and thus reach the extended position. Given the above-described reversibility, it is possible by means of steps that are the converse of those implemented for assembly, to remove the implant from its position between the vertebrae.
In the third embodiment, as shown in FIGS. 8 and 9 in which some of the numerical references have 400 added thereto, the body 4 in plane view generally has the shape of half a disk, being defined by a plane side wall 8 for occupying the posterior position and a circular side wall 8 for occupying an anterior position. Each side wall 8 has orifices 12 opening out into the recesses 10 as described above. In this case, the body 4 comprises a top portion 4 a and a bottom portion 4 b which meet in a joint plane parallel to the top and bottom faces 6 , with each portion carrying one of said faces 6 and being fixed to the other by means of screws 5 . There are still twelve channels 22 , but they are oriented so that their axes are perpendicular to the top and bottom faces 6 .
The cam duct 14 has a section that is generally rectangular in shape perpendicularly to its axis 16 and half of it is defined in each of the portions 4 a and 4 b of the body. The cam 430 has a male rectangular section corresponding to the female rectangular section of the duct 14 which receives it. It is suitable for sliding along its axis. The cam is generally in the form of a rectangular parallelepiped. The two longitudinal side faces 460 of the cam 430 have six slots 454 each suitable for receiving respective specific pins 26 . To this end, instead of having a head, each pin has a respective projection that is received in the slot so that each pin is generally L-shaped, with the projections extending towards the other row of pins. Each slot 454 presents two mutually-parallel plane ramps or faces 462 that are perpendicular to the associated side face 460 , and that slope relative to the sliding direction in such a manner that the end of the slot 454 that is further away from the associated face 6 is its end which is further away from the proximal end of the cam.
The cam 430 presents a threaded bore passing through it along its axis. The implant 402 has a screw 450 presenting a threaded rod suitable for screw co-operation with the cam 430 . The screw 450 has a groove receiving a collar 466 that is secured to the body 450 that the screw 450 is free to rotate in the body while the cam 430 is free to slide in the body.
After the implant 402 has been inserted between the vertebrae 9 with the pins 26 in the retracted position, when the head 436 of the screw is driven, rotation of the screw causes the cam 430 to slide towards the distal end of the duct 14 , which end is closed in this case, and by the effect of the ramps in the faces 462 of the slots oriented towards the associated faces 6 , the pins 26 are caused to slide so as to project and take up the extended position.
The operation of the implant 402 is reversible, with the faces 462 of the slots that face away from the associated faces 6 being suitable for moving the pins 26 into the retracted position when the cam 430 slides towards the proximal end of the duct 14 . Specifically, the proximal end associated with the head of the screw 436 opens out into the left-hand portion of the curved side wall 8 . The pins 26 in this case present circumferential grooves 70 in the vicinity of their points on the segments thereof that are designed to project, with the grooves presenting respective faces that are undercut relative to the direction in which the pins slide so as to project, and the grooves improve anchoring of the pins by enabling bone growth to take place in the grooves.
FIGS. 10 and 11 show a fourth embodiment with some of the reference numerals having 400 added thereto. In this case there are four pins 26 in each face 6 and they are oriented in the same manner as in the third embodiment. The slots 562 are analogous to those of the third embodiment but they are oriented in the opposite direction so that sliding the cam 530 towards the distal end of the cam duct 14 causes the pins 26 to project. The implant 502 has a screw 550 in screw engagement with the body 4 on the axis of the cam duct and suitable for urging the cam 530 at its proximal end in its duct towards the distal end of the duct.
With reference to FIG. 12, the proximal end of the cam has a cutout 572 suitable for slidably receiving the end of the screw 550 so that it can bear against the cam 530 . Between the far wall of the cutout and its edge, the cam 530 presents a slot 574 with a flank 576 that presents an undercut relative to the cam sliding towards the proximal end of the duct. By way of example, this face 576 can be an annular plane perpendicular to the axis 16 of the cam and facing away from the proximal end.
In order to remove the implant, the screw 550 is removed and then a tool is inserted into the duct 14 that is suitable for bearing against the undercut face 576 as to catch hold of it and pull the cam towards the proximal end of the duct, thereby causing the pins 26 to be moved into the retracted configuration. This embodiment avoids the need to provide a threaded bore passing through the cam 530 . It thus enables the dimensions of the cam 530 to be reduced and the dimensions of the recesses 10 for receiving graft tissue to be increased.
A fifth embodiment of the implant is described with reference to FIGS. 13 to 17 . The implant 602 comprises a body 4 whose plane is general in the shape of a bean whose hilum is in the posterior position, the body being flat in one direction so as to define two large faces 6 , namely a top face and a bottom face, and a peripheral side wall 8 . The top and bottom faces 6 are generally plane in shape with a transverse profile that is sawtoothed or zigzag, the tips of the teeth defining mutually-parallel continuous edges. These teeth provide good engagement between the top and bottom faces 6 and the plates of the vertebral bodies of the vertebrae constituting the destination location.
The body 4 has two through recesses 10 extending between the top and bottom faces 6 and opening out into them. When the implant is put into place, the recesses 10 are filled with graft tissue which can thus grow towards the vertebral plates through the recesses 10 .
The body 4 has a cylindrical duct 14 whose axis 16 extends between the recesses 10 parallel to the general planes of the top and bottom faces 6 and is separated from the single plane portion of the side face 8 by one of the recesses 10 . The duct 14 opens out at only one of its ends.
The body 4 has two channels 22 opening out into each of the top and bottom faces. Each channel 22 is of constant section along an axis perpendicular to the main faces and in section its profile is rectangular with rounded ends. Each channel opens out on one side over its entire height into a respective one of the recesses 10 with which it is contiguous. Furthermore, it opens out sideways on its opposite side in its middle portion into the duct 14 . The two channels 22 extend in register with each other on either side of the duct 14 . The channels 22 thus put the two recesses 10 into communication with the duct 14 .
In the vicinity of each of the main faces, each channel 22 receives a pair of anchoring elements each in the form of a pin 26 having a smooth cylindrical body presenting a point at its end closer to the face 6 . Each pin 26 extends against a respective curved edge of the channel so as to slide there against perpendicularly to the main face 6 of the body.
The implant includes two pin-carriers or anchoring element-carriers 680 associated with respective main faces 6 . Each pin-carrier 680 is generally in the form of a flat H-shape having two rectangular branches 682 parallel to each other and a middle segment 684 interconnecting the middles of the branches. Each pin-carrier 680 has rigidly fixed thereon all four pins 26 associated with the corresponding main face 6 . The bases of the four pins 26 rest on respective ends of the branches 682 , and all lie on the same side of the pin-carrier. The two pin-carriers 680 extend permanently in register with each other so that their outlines coincide, and regardless of whether the pins 26 are in the extended or retracted position, as shown in FIGS. 15 and 16. The branches 682 extend in respective channels 22 and have the same profile, while the middle segment 684 extends across the duct 14 .
The implant has a cam 630 with left and right cylindrical faces 631 that are left and right at the rear, and top and bottom at the front, for the purpose of slidably guiding the cam in the cylindrical duct 14 . The “rear” of the cam is its end closest to the mouth of the duct 14 . For each pin-carrier 680 , the cam 630 has a corresponding slideway 633 and bearing surface 635 that can be seen in particular in FIGS. 14 and 17. The slideway 633 is formed by a very flat duct open to both longitudinal edges and sloping relative to the axis 16 , going towards the corresponding main face when going from the front end towards the middle of the cam. The slideway 633 is closed at its front end and open at its rear end, with the inner face 641 of the slideway extending continuously from the bearing surface 635 . This surface is parallel to the axis 16 and to the associated main face 6 . The middle segment 684 can be moved by thrust against the slideway 633 and the bearing surface 635 as explained below. The sloping slideways 633 and the parallel bearing surfaces 635 give the cam a shape reminiscent of a boat anchor.
At its rear end, the cam has a tapped bore 637 whose thread can mesh with that of a suitable tool for driving the cam by pushing it or pulling it.
The implant is used as follows, with the pins 26 initially being in the retracted position as shown in FIG. 15 . After a vertebral disk has been removed and after the recesses 10 have been filled with graft tissue as described above, the implant 2 is inserted between the vertebral bodies of the vertebrae associated with the disk that has been removed. The height of the body 4 of the implant corresponds substantially to the thickness of the removed disk. The faces 6 extend in register with the respective vertebral plates, parallel thereto, and in contact therewith. The cam is close to the mouth of the duct 14 , at the rear.
The tool is screwed into the bore 637 of the cam and the cam 630 is pushed forwards. The ramp acting on each middle segment 684 via the inner face 641 of the associated slideway 633 causes the pin-carrier 680 together with the four pins 26 to move perpendicularly to the main face 6 .
After the pins 26 have been caused to project from the main face 6 , continued thrust on the cam causes the middle segment 684 to bear against the bearing surface 635 as shown in FIG. 14, thus locking the pins 26 in the extended position where the anchor in the vertebral plates. The tool is then unscrewed so as to be separated from the cam.
However, if it is desired to remove the implant, the tool is reconnected in the bore 637 of the cam via the duct 14 and then the cam is pulled so as to slide rearwards. The middle segment 684 then follows the bearing surface 635 and, by ramp engagement against the outer face 643 of the slideway 633 , it becomes moved towards the axis 16 towards the inside of the implant, thereby retracting the pins 26 so that they no longer project. The cam thus enables the pins 26 to be driven in both directions, i.e. reversibly.
By having all four pins 26 in each group fixed together, it is possible to obtain very accurate guidance for the pins in the channels 22 without needing to provide a cylindrical channel for each pin. In addition, this guidance is obtained using a single two-part ramp surface 641 , 635 , or 643 for all four pins in any one given displacement direction.
At the base of the point forming its tip, each pin 26 has circular grooves 70 forming undercut zones and improving the anchoring of the pin in the vertebral plate.
The body 4 is made up of two portions that are assembled together on a joint plane (not shown) parallel to the main faces 6 and including the axis 16 , thereby enabling the cam 630 and the pin-carriers 680 to be inserted in the body.
Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. | The intersomatic spine implant comprises a body, at least one anchoring element movable relative to the body to project from a contact face of the body making contact with a vertebra, and at least one cam slidable relative to the body and suitable for displacing the anchoring element relative to the body by the effect of a ramp engaging the anchoring element. The cam and the anchoring element are arranged so that the cam moves the anchoring element in two opposite displacement directions. | 0 |
BACKGROUND OF THE INVENTION
The invention provides a lift blade and engagement shed-forming apparatus for a textile machine and, in particular, a loom.
One form of shed-forming device for a textile machine, comprises lift blades which are movable in opposite relationship to each other, and hooking engagement elements which can be engaged by the lift blades in a hooking engagement position, and which are connected in pairs by flexible connecting members forming loop configurations. The device further includes rollers carried in the loops, operatively connected to the shedding means, such as the heald train or harness train of the textile machine. Stationary electromagnetic means act on the hooking engagement elements holding the elements in position and are adapted to be actuated by way of program carriers.
In the preferred embodiment of the invention each of the pair of hooking engagement elements is capable of being positioned in either of two discrete vertical locations. Specifically, when one of the hooking engagement elements is in the engaged position, i.e., engaged by the lift blades and moved upwardly into the upper-shed position, the other of the pair of hooking engagement elements is held in a lower-shed position. In the preferred embodiment, one element is retained in the upper-shed position if a change in shed is to be effected by the harness connected to the roller.
Another device of the general kind outlined above is disclosed, in European patent specifications Nos. 0 188 074 and 0 119 787. In those devices the hooking engagement element must be attracted by the magnets across a respective air gap in order to be held in a desired position. Thus, the part of the hooking engagement element to be attracted by the magnet means is of a long and blade-like configuration. This air gap requires that the electromagnet device produce a strong attractive force, which, inter alia, gives rise to a relatively high level of power consumption. Furthermore, this arrangement produces a large amount of heat, and requires a large space to accomodate an appropriate electromagnet.
The shed-forming device disclosed in European patent specification No. 0 219 437, operates with a weak electromagnet means; however, that configuration does not involve any air gap which has to be traversed. To provide such a design configuration, the arrangement requires additional arresting elements; e.g., pivotal levers which are additionally supported with hooks and springs. Accordingly, the additional mounting means subject the levers to heavy loadings and, in general, the additional components result in greater expense and increased incidences of malfunction.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a shed-forming device which does not suffer substantially from the above-mentioned disadvantages.
Another object of the invention is to provide a shed-forming device for a textile machine in which a magnetic force required to produce an arresting position of the arrangement does not have to act across an air gap.
Still another object of the present invention is to provide a shed-forming device for a textile machine, such as a loom, which involves a small number of movable components while affording reliability of operation of the arrangement.
The invention provides a lift blade and hooking engagement shed-forming apparatus for a textile machine such as a loom. In particular, the invention includes lift blades (e.g., 1,2,3) capable of opposing movement and hooking engagement elements (e.g., 4,4',4") adapted to be engaged by the lift blades in a hooking engagement position. The hooking engagement elements are connected in pairs by flexible connecting members (e.g., 9) forming a loop therebetween. Rollers (e.g., 12) which are carried in the respective loops, are operatively connected to the shedding means (e.g., 13) such as the heald train or harness train of a textile machine. Stationary electromagnets (e.g., 5) are operatively arranged to contact the hooking engagement elements and further adapted to be actuated by way of program carriers and a power source (e.g., 16). Each hooking engagement element is adapted to be supported by a support leg (e.g., 8) adapted to engage a stationary support bar, (e.g., 17) disposed at the level of the lower-shed position of the hooking engagement elements. The support leg is adapted to fit into a channel recess (e.g., 18) in a stationary support bar (e.g., 17) when the hook engagement element is in the lower-shed position. The channel recess is specially configured such that the hook engagement element is able to pivot toward and away from the attendant electromagnet. Pivoting of the hook engagement element is facilitated by the contacting of sliding surfaces (e.g., 21) of the lift blade which, in the lower-shed position, slides against a projection (e.g., 19) on the hook engagement element.
To facilitate movement to the upper-shed position, a hook portion (e.g., 7) is arranged on the hook engagement element capable of receiving complementary hook portions (e.g., 20) of the lift blades as the lift blades are driven upwardly.
Thus, in operation, as one lift blade engages the corresponding hooking engagement element and pulls the element to the upper-shed position in order to effect a change of shed, the other lift blade of the pair slides against the corresponding hooking engagement element pivoting the element against the electromagnet in the lower-shed position whereby, upon actuation of the electromagnet, the hooking engagement element is held in the lower-shed position.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic view of a shed-forming device with a lower-shed position and an upper-shed position, and
FIG. 2 shows a hooking engagement element according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Adverting to FIG. 2, the invention is shown to include a plurality of lift blades 1, 2 and 3 adapted to be moved upwardly and downwardly by a suitable drive arrangement (not shown). Lift blades 1, 2 are shown to be at the bottom dead center position of their lift movement, while lift blade 3 is shown at the top dead center point of the lift movement. The device further comprises hooking engagement elements 4, 4', 4" shown in various positions. Specifically, hooking engagement elements 4 at the extreme right and the extreme lift in FIG. 1 are in a pivoted condition and are attracted by an electromagnet 5.
Continuing to refer to FIG. 1, hooking engagement element 4' has been moved into the top dead center point of the movement by lift blade 3.
Similarly, FIG. 2 also shows a hooking engagement element 4" in the lower-shed position, but not pivoted towards and into contact with electomagnet 5.
Adverting to FIG. 2, hooking engagement element 4 is shown to include an elongated, specially configured main body portion 6, typically formed of plastic, which at its upper end has a hook means 7 and at its lower end, a support leg 8. Formed on the body portion, intermediate the hooking means and support leg, is a connecting element 9 having a spring tongue-like portion which is connected at its lower end to a clip hook 10. A pair of hooking engagement elements can be connected by appending the clip hooks to flexible connecting members 11 thereby forming a loop. Disposed within the loop is a roller 12 to which a selected shedding means, such as a harness train 13, is operatively connected.
Hooking engagement element 4 also includes a magnetic armature 14 arranged to face the electromagnet when the hooking engagement element is in the lower-shed position. This configuration is illustrated by the extreme right-hand hooking engagement element of FIG. 1.
Continuing to advert to FIG. 1, electromagnets 5 are each operatively arranged at stationary locations between connected pairs of hooking engagement elements and are supplied with electrical power and actuated by power lines 15 and related electronic components 16.
Also disposed at stationary locations are support bars 17, each of which have channel-like recesses or openings 18 for receiving the support legs 8 of the hooking engagement elements when in the lower-shed positons. The recesses are so that, when the hooking engagement elements are not pivoted into position against the hooking engagement elements support legs 8 bear against the upper side of the recess which forms a stop or abutment 22. Similarly, the lower portion of each recess is adapted to the rounded configuration of the support leg, while, the upper portion is wider to provide a gap in which the support leg can pivot against the respective electromagnet. Continuing to advert to FIG. 1, such pivotal movement is produced by the respective lift blade 1, 2 or 3 as it moves downwardly past the respective hooking engagement element 4, 4', 4". For that purpose, each hooking engagement element 4 includes a projection 19 which projects into the path of movement of the respective lift blade when the hooking engagement element is not pivoted into contact with the electromagnet.
Each lift blade is also provided with hook portions 20 which co-operate with the projection 19 and with sliding surface 21. Thus a lift blade comes into contact with an associated hooking engagement element, projection 19 and the sliding surface 21 come into sliding contact with each other, and the hooking engagement element is pivoted into position against the respective electromagnet. Specifically the hooking engagement element magnet armature bears against the associated electromagnet without an air gap therebetween, so that the magnetic forces produced by the electromagnet upon actuation thereof do not have to traverse an air gap in order to arrest the hooking-engagement element.
Continuing to advert to FIG. 1, the connecting element 9 connected to the respective hooking engagement element 4 is disposed in the direction of the line of pulling force, as can be seen, for example, by considering lift blade 3 and hooking engagement element 4' associated therewith. Support leg 8 of the hooking engagement element however, is arranged outside the pulling force line. Accordingly, the hooking engagement element takes up the hooking engagement position on account of the pulling force applied thereto by the shedding means, such as the heald or harness train of the machine.
It will be appreciated that the above-described construction has been set forth solely by way of example and illustration of the principles of the present invention and that various modifications and alterations may be made therein without thereby departing from the spirit and scope of the invention.
This arrangement affords the advantage that the positive movement of the lift blade means that the hooking engagement element is pivoted into a holding position in which the hooking engagement element bears against the electromagnet means without an air gap therebetween so that the hooking engagement element is held fast in that position, when the electromagnet means is activated, without having to overcome or traverse an air gap. On the other hand, the action of the support leg means and the support bar and the effect of the return pulling force of the shedding means, such as the harness or heald arrangement of the machine, means that the hooking element can be pivoted into the hooking engagement position. In that way, no additional components or members are required for moving the element which is to be arrested by the electromagnet means, towards same, with the result that the electromagnet means can be of small sizes. That, in turn, results in the assembly occupying a small amount of space and having a low level of power consumption. In addition, only a small number of movable components are involved, and that in turn means that the frictional forces involved in operation of the arrangement are low, assembly is a simple matter, manufacturing costs can be kept down, and the susceptibility to trouble of the assembly is also low, which results in a low repair and maintenance requirement. In the shed-forming device according to the invention, therefore, the hooking engagement element on the one hand performs the lift movement, while, on the other hand, it can be readily pivoted into the hooking engagement position without the magnetic force having to act across an air gap.
In a preferred feature of the invention, the support leg means may be arranged outside the line of pulling force between the holding means and the loop-forming connecting member, in such a way that the hooking engagement element is pivoted into the hooking engagement position by the shedding means, such as the heald or harness train. That design configuration means that the hooking engagement element is caused to pivot into the hooking engagement position without the use of additional components, such as springs or the like, by virtue of the pulling force of the shedding means of the textile machine. The arrangement may also be such that the hooking engagement element is pivoted in the opposite direction, that is to say towards the electromagnet means, by the shedding means of the machine.
Another advantageous feature of the invention provides that the hooking engagement element comprises a main body portion with a hooking means formed at one end thereof, a support leg formed at the other end thereof, and a connecting element which is of a spring tongue-like configuration and which is formed between the hooking means and the support leg. That arrangement provides the advantage that, due to the spring tongue-like connecting element, not only can the hooking engagement element perform a pivotal movement, but, in addition, the spring action of the connecting element has at the same time the positive effect that the movement of the hooking engagement element into the hooking engagement position can be boosted and materially assisted thereby.
Another preferred feature of the invention may provide that the hooking engagement element is made in one piece from plastic material and has a magnet armature at the side thereof which is towards the electromagnet means in the lower-shed position. That arrangement gives the advantage that both in the condition of hooking engagement with the lift blade, which generally comprises metal, and also in the condition of being supported against the support bar, which preferably comprises metal, contact occurs between plastic material and metal, which permits a lubrication-free mode of operation. Furthermore, that design configuration means that the hooking engagement element can be manufactured in a simple procedure using an injection molding process without subsequent trimming, finishing or like machining operations being required. The above-mentioned magnet armature may be provided on the hooking engagement element for example in manufacture thereof by being injection-molded therein of thereon or by being subsequently attached thereto, as by clipping, adhesive or in some other suitable fashion.
Another feature of the invention may provide that the hooking engagement elements each have a projection which projects into the path of movement of the respective lift blades in the hooking engagement position of the hooking engagement elements, and the lift blades, on hooking portions htereof which co-operate with the hooking engagement elements, have sliding surfaces so that when contact occurs between those sliding surfaces and the projections on the hooking engagement elements, the latter are pivoted into one of the pivotal positions, preferably the position of bearing against the electromagnet means. In that way, the hooking engagement elements can be moved closely to the electromagnet means so that the magnetic force produced thereby for holding the hooking engagement element in position does not have to overcome an air gap, with the result that the electromagnet means can be of a smaller capacity as they only have to produce a lower level of attraction force. | A shed-forming device for a textile machine which includes lift blades (e.g., 3) arranged to hookingly engage or slidably contact an associated hooking engagement element (e.g., 4) such that the hooking engagement element is either lifted into an upper shed position to effect a shed change or alternatively, is pivoted into an arrested lower shed position by the attractive force of an associated electromagnet (e.g., 5). The hooking engagement elements are arranged in pairs by flexible connecting elements (e.g., 9) which form a loop into which is disposed a roller (e.g., 12) operatively attached to a shed such as a harness (e.g., 13). A pulling force generated by the movement of the roller and harness serves to pivot or position the hooking engagement element for cooperation with the lift blades and accordingly, facilitates changing of the harness. | 3 |
CROSS REFERENCE TO RELATED APPLICATION
This is a Continuation of Ser. No. 11/038,202 filed on Jan. 21, 2005 now U.S. Pat. No. 7,204,482, which is a Continuation of Ser. No. 10/740,414 filed on Dec. 22, 2003, now granted U.S. Pat. No. 6,860,479, which is a continuation of Ser. No. 09/721,860 filed on Nov. 25, 2000, now abandoned, all of which are herein incorporated by reference.
FIELD OF THE INVENTION
The following invention relates to spine pressing in a page binding machine. More particularly, though not exclusively, the invention relates to pressing an edge portion of a stack of pages where each page has binding adhesive pre-applied to at least one surface adjacent the edge.
It is well known to print individual pages of a volume to be bound, then to place all of the printed pages into a stack, to then crop one or more edges of the stack and to then bind the pages together by applying a binding adhesive to an edge of the stack of pages. This is a time consuming and labour-intensive process.
It would be more efficient to provide pre-cut, uniformly sized pages, to print one or both surfaces of each page and to provide a strip of binding adhesive to one or both surfaces of each page adjacent the edge to be bound, to accurately place the printed and pre-glued pages in a stack, and to press the pages adjacent the spine so that the adhesive binds the page edges together.
OBJECT OF THE INVENTION
It is the object of the present invention to provide a method and apparatus for pressing a spine portion of a stack of pre-glued pages.
DISCLOSURE OF THE INVENTION
According to one aspect of the invention there is provided a printer comprising:
(a) a print engine for printing on pages; and (b) a page binding apparatus for binding at least some of the printed pages, the binding apparatus comprising:
(i) an adhesive application station including a first and a second adhesive applicator, the first applicator being arranged to apply a first part of a two-part adhesive onto one side of a page, the second applicator being arranged to apply a second part of the two-part adhesive onto an opposite side of the page; (ii) a tray for receiving pages from the adhesive application station, the tray having: (iii) a support surface for supporting a stack of pages, the support surface being inclined towards a lower-most corner; and, (iv) two side walls defining a corner situated at the lower-most corner of the support surface; (v) a vibrator coupled to the support surface to induce vibration therein to thereby urge sheets towards the lower-most corner; and (vi) a binding press operable by moving through a stroke length to bear upon the stack of pages to thereby bind the pages.
According to another aspect of the invention there is provided an apparatus comprising:
a support surface for supporting a stack of pages, at least some of which have adhesive applied to at least one surface adjacent an edge, and
a binding press operable to bear upon the stack of pages adjacent an edge of the stack so as to compress the adhesive and bind the pages.
Preferably the pages have binding adhesive applied to an upper side of all but the top page.
Alternatively, the pages have binding adhesive applied to a bottom side of all but the bottom page.
Alternatively, a first part of a two-part adhesive is applied to the top surface of all but the top page and a second part of a two-part adhesive is applied to the bottom surface of all but the bottom page.
Preferably the binding press is forced by a mechanical drive toward the support surface upon which the stack of pages rests.
Preferably the mechanical drive includes a pneumatic and/or hydraulic cylinder or cylinders.
Alternatively, the mechanical drive includes a rack attached to the press and a pinion meshing with the rack and driven by a motor.
Alternatively, the mechanical drive includes a pivot arm to which there is affixed a plurality of disks or arms which press down upon the stack upon pivotal rotation of the pivot arm.
Preferably the support surface is a bottom floor of a tray.
Preferably each page is delivered to the tray such that the pre-glued edge is a leading edge of the page.
Alternatively, each page is delivered to the tray such that the pre-glued edge is a trailing edge of each page.
Preferably the floor of the tray is adjustable vertically so as to present an upper page of the stack at a preset level to limit the stroke length of the binding press.
There is further disclosed herein a method of binding pages of a volume, the method including the steps of:
providing a plurality of uniformly sized pre-printed pages with at least some of the pages having binding adhesive applied to at least one side adjacent an edge thereof,
placing the pages one above another in a stack,
ensuring alignment of the pages, and
pressing at least a portion of the pages so as to compress the adhesive so as to adhere the pages together.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred forms of the present invention will now be described by way of example with reference to the accompanying drawings wherein:
FIG. 1 is a schematic illustration of a page conveyed along a path and passing a pagewidth print head and an adhesive applicator;
FIG. 2 is a schematic illustration of a page having an adhesive strip adjacent one edge thereof;
FIG. 3 is a table, schematically illustrating the principles of five alternative adhesive application methods;
FIG. 4 is a schematic elevational view of a number of pages with all but the top page having a strip of adhesive applied to an upper surface adjacent to an edge to be bound;
FIG. 5 is a schematic elevational view of a stack of pages with all but the bottom page having a strip of adhesive applied to a lower surface thereof adjacent to an edge to be bound;
FIG. 6 is a schematic elevational view of a stack of pages with a first part of a two-part adhesive applied to the upper surface of all but the top page and a second part of a two-part adhesive applied to the bottom surface of all but the bottom page,
FIG. 7 is a schematic perspective view of a page binding support tray situated immediately down-line of the adhesive applicator,
FIG. 8 is a schematic cross-sectional elevational view of the page binding support tray of FIG. 7 showing a first page having a strip of adhesive adjacent its edge at an upper surface en route thereto,
FIG. 9 is a schematic cross-sectional elevational view of the page binding support tray and page of FIG. 8 , with the page closer to its rest position,
FIG. 10 is a schematic cross-sectional elevational view of the page binding support tray and page of FIGS. 8 and 9 , with the page at rest thereon,
FIGS. 11 , 12 and 13 are schematic cross-sectional elevational view of the page binding support tray showing a second page as it progresses to rest upon the first page,
FIG. 14 is a schematic cross-sectional elevational view of the page binding support tray having a number of pages resting thereon to be bound, with all but the top page having an upwardly facing strip of adhesive adjacent an edge thereof,
FIG. 15 shows the progression of a page-binding press toward the edge of the stacked pages,
FIG. 16 shows the page binding support tray with pages bound along their edge by application of the binding press,
FIG. 17 is a cross-sectional elevational view of the page binding support tray having a number of individual volumes resting thereon, with a top volume ready to be pressed,
FIG. 18 is a schematic cross-sectional elevational view of the page binding support tray and volumes of FIG. 17 , with all volumes having been pressed, one upon another,
FIG. 19 is a schematic perspective illustration of a number of volumes having been bound,
FIG. 20 is schematic elevational view of a page binding support tray having an alternative press,
FIGS. 21 and 22 are schematic perspective views of a portion of the alternative press of FIG. 20 , and
FIG. 23 is a schematic elevational view of a page binding support tray having an alternative press at a trailing edge of a stack of pages to be bound.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 of the accompanying drawings there is schematically depicted a path 10 of a page 11 passing through a printer incorporating an adhesive applicator.
Page 11 is driven to the right at a driving station D. Driving station D might comprise a pair of opposed pinch rollers 12 as shown. The page 11 then passes a printing station P and then an adhesive application station A. As an alternative, the adhesive application station A might precede the printing station P, but it is preferred that the adhesive application station follow the printing station so that adhesive on the page 11 does not clog the print head or print heads at printing station P.
For single sided page printing, the printing station P might comprise a single print head 13 . The print head 13 might be a pagewidth drop on demand ink jet print head. Alternatively, the print head might be that of a laser printer or other printing device. Where the page 11 is to be printed on both sides, a pair of opposed print heads 13 might be provided.
Where the print heads 13 are ink jet print heads, wet ink 15 on page 11 might pass through the adhesive application station A.
An air cushion 14 at either side of the page 11 as it passes printing station P can be provided by means of air passing through an air flow path provided in each print head 13 .
The adhesive application station A can comprise an adhesive applicator 16 at one or both sides of the page 11 , depending upon which side or sides of the page to which adhesive is to be applied.
As shown in FIG. 2 , a page 11 having matter printed thereon by printing station P also includes a strip 17 of adhesive as applied at adhesive application station A.
As can be seen, the strip 17 can be applied adjacent to the leading edge 27 of page 11 . The application of strip 17 adjacent to the leading edge 28 is suitable for those situations where the adhesive applicator does not contact the page, or contacts the page at a velocity accurately matching that of the page 11 as it passes the adhesive application station A. Alternatively, the strip 17 could be applied adjacent to the trailing edge 28 of page 11 and this position might be more suited to adhesive applicators that make some form of physical contact with the page 11 as it passes adhesive application station A.
A margin 29 of about 1 to 2.5 mm is desirable between the strip 17 and edge 27 or 28 of page 11 .
Various methods of applying adhesive to the page 11 are envisaged, some of which are schematically depicted in FIG. 3 .
Method 1 in FIG. 3 is a non-contact method of applying adhesive to the moving page 11 . In this method, a stationary adhesive applicator 16 sprays adhesive on one side of page 11 as it passes the applicator. The adhesive applicator might be formed integrally with the print head 13 or might be located upstream or after the print head.
Method 2 also applies adhesive to one side of the moving page 11 , although this time using a contact method. An adhesive applicator 16 is pivotally mounted about a fixed pivot point and is caused to move at a speed matching that at which the page 11 passes through the adhesive application station. A reaction roller 30 comes into contact with the underside of page 11 as the adhesive applicator 16 applies adhesive to the page.
Method 3 applies adhesive to both sides of a page 11 as it passes through the adhesive application station. A pair of pivotally mounted adhesive applicators 16 move pivotally at a speed corresponding with that at which the page 11 passes through the adhesive application station. They both come into contact with the page 11 and mutually counteract each other's force component normal to the page 11 .
Method 4 employs a pair of adhesive applicator rollers 16 spaced from either side of the page 11 until activated to apply adhesive whereupon they move toward and touch the page 11 , leaving a strip of adhesive 17 at either side of the page. The rollers would mutually counteract each other's force component normal to page 11 .
Method 5 employs a pair of adhesive spray applicators 16 ,one at either side of page 11 . The applicators do not contact page 11 . Each applicator would apply one part of a two-part adhesive to a respective side of page 11 so as to apply strips 17 a and 17 b. Like Method 1 , Method 5 could employ an adhesive applicator formed integrally with the print head. That is, a channel for the flow of one part of a two-part adhesive might be provided in each print head.
Also, the use of a two-part adhesive could be beneficial in situations where there might be some delay in the printing/binding operation. For example, if there were a computer software or hardware malfunction part-way through a printing/binding operation, the use of a two-part adhesive could provide sufficient time within which to rectify the problem and complete the binding process.
FIG. 4 illustrates a stack of pages 11 with all but the top page provided with an adhesive strip 17 at an upper surface adjacent one edge to be bound.
An alternative is depicted in FIG. 5 wherein all but the bottom page has an adhesive strip 17 applied to its bottom surface adjacent an edge to be bound.
In FIG. 6 , a stack of pages is shown with part A of a two-part adhesive applied to the upper surface of all but the top page and the second part of the two-part adhesive applied to the bottom surface of all but the bottom page.
When the stacks of pages of FIGS. 4 and 5 are pressed together, adhesion of the pages occurs once the adhesive 17 has dried.
When the pages 11 of FIG. 6 are pressed together, the respective parts of the two-part adhesive in strips 17 a and 17 b combine so as to react and set.
Where print head 13 is an ink jet print head, and non-contact adhesive application Methods 1 and 5 are employed, the adhesive strip 17 is applied to page 11 before ink on the page passing through the adhesive application station 10 has dried. Air passing through air gap 14 accelerates the drying process. That is, adhesive is applied to the page as it passes out of the print head 13 . The velocity of the page 11 does not change as a result of the application of adhesive strip 17 .
Where the strip 17 is applied alongside the leading edge 27 of the page 11 , any alteration to the velocity of page 11 would adversely affect print quality. Hence application of adhesive strip 17 alongside the leading edge 27 is only possible without adversely affecting print quality using non-contact adhesive application methods or methods where the velocity of the adhesive applicator coming into contact with the page is very close to that of page 11 .
Where the adhesive strip 17 is applied alongside the trailing edge 28 of page 11 , a non-contact method or method of very close speed matching is also desired. For example, if the speed of the adhesive applicator of Methods 2 to 4 was faster than that at which the page 11 was passing the print head, the page could buckle.
A most desirable embodiment of the present invention would use a two-part adhesive and would incorporate the adhesive applicators within the print heads themselves. That is, a passage or passages for the flow of adhesive through the print head would be space and cost-effective.
The likelihood of adhesive “gumming” and blocking such channels would be diminished where a two-part adhesive was employed. That is, only one part of the two-part adhesive would pass through any particular channel or channels of the print head.
Where respective parts of a two-part adhesive are applied to opposed sides of pages 1 1 , those respective parts could pass through dedicated channels in the respective print head at either side of the page. This would greatly reduce the likelihood of adhesive blockages in the flow channels.
The adhesive or respective parts of a two-part adhesive can be provided in a chamber of a replaceable ink cartridge providing ink to the print head.
The print head 13 should be as close a possible to the pinch rollers 12 . This is because the rollers 12 provide a mechanical constraint upon the page 11 to enable accuracy of printing.
The pinch rollers 12 , print heads 13 and adhesive applicator 16 are illustrated in FIG. 7 alongside a page support tray 18 . That is, the page support tray 18 receives pages 11 that exit the paper path 10 . The tray 18 is suspended from a frame 21 by means of respective dampers 22 at each corner. The dampers could be elastomeric dampers or small hydraulic or pneumatic cylinders for example. The floor of tray 11 is not level. It has a lower-most corner 23 beneath which there is provided a vibrator 19 . The vibrator 19 might be a subsonic vibrator (ie a vibrator having a frequency below 20 hz) or an out-of-balance electric motor for example. A binding press 20 is situated above the tray 18 over the at-rest position of the respective leading edge of the pages 11 . However, as an alternative, the binding press 20 could be provided so as to be situated over the trailing edge of the pages.
In FIG. 8 a first page 11 is shown in its trajectory toward tray 18 . Page 11 has a strip of adhesive 17 on its upper surface adjacent the leading edge. The page 11 might tend to catch a pocket of air beneath it as it floats into position and the leading edge 28 might strike the vertical wall 31 as shown in FIG. 9 . The vibrations of the tray 18 as a result of the vibrator 19 will cause the page 11 to come to rest with edge 27 alongside the lower edge of wall 23 and with a right angled edge of the page touching the front wall 32 of tray 18 .
In FIG. 11 , a second page 11 is shown in its trajectory toward tray 18 . In a motion similar to that of the first page, the second page comes to rest upon the first page in a position perfectly aligned therewith. The second page comes to rest into the position depicted in FIG. 13 . Where the pages have the adhesive strip 17 applied to the upper surface, the final page is provided without any adhesive and it comes to rest at the top of the stack as depicted in FIG. 14 . If, instead, the majority of pages 11 had the adhesive strip 17 applied to their bottom surface, the first page (ie the page at the bottom of the stack) would have no adhesive applied to it. This would be suitable for multiple binding compressions.
As shown in FIG. 15 , the binding press 20 commences downward movement toward the stack of pages 11 over the aligned adhesive strips 17 . The stack is then compressed to a bound volume 24 as shown in FIG. 16 .
It should be noted that no subsequent edge trimming of the bound volume is required so long as standard-sized pages 11 had initially been used. This is because the vibrator 19 has aligned the pages into the lower-most corner 23 of tray 18 as described earlier.
In FIGS. 17 and 18 , multiple volume 24 are shown stacked on upon another with the upper-most volumes being progressively compressed by repeated application of press 20 .
The binding press 20 is shown schematically in the Figures and could be pneumatically or hydraulically driven, or could be driven by other mechanical means such as rack and pinion, electrical solenoid or otherwise. An alternative embodiment as depicted in FIGS. 20 , 21 and 22 incorporates a plurality of semicircular disks 20 each spaced apart, but fixedly mounted to a common rotatably driven shaft extending along an axis of rotation 26 . Each disk 20 could pass through a respective vertical slot 32 formed in the end wall 31 of tray 18 . That is, there would be as many vertical slots in wall 31 as there are disks 20 . The disks could commence in the orientation depicted in FIG. 21 and upon rotation of the shaft pivot to the orientation depicted in FIGS. 20 and 22 so as to press down upon the pages.
The tray 18 might be provided with a floor of adjustable height so as to always present the top page in the tray closely to the pressing device. This would reduce noise levels by minimizing the stroke length of the binding press 20 . Furthermore, the binding press 20 could be fixed and the tray could be pushed upwardly toward it to press and bind the pages.
The floor of tray 18 can be driven so as to move downwardly as each page 11 is delivered thereto. This would ensure that the upper-most page always resided at the same level. This could result in reduced noise of movement of the press bar 20 as it need not move very far to effectively bind the pages.
Where the pages have applied thereto adhesive strips alongside the trailing edge 28 , the press would be provided to the left as shown in FIG. 23 . In this embodiment, a pressing bar 20 is provided. Any pressing arrangement could however be provided. | A printing arrangement includes a driving station configured to drive print media along a path. The driving station includes a pair of opposed pinch rollers between which the print media can be pinched when driven. A printing station is operatively arranged with respect to the path to print upon the print media. The printing station includes a pair of opposed printheads between which the print media can pass to be printed on opposite sides. An adhesive application station is operatively arranged with respect to the path to apply adhesive to the print media. A binding station is operatively arranged with respect to the path to collect the printed media in a stack and press the stack to facilitate adhering of the printed media together. | 1 |
This is a division of application Ser. No. 875,846 filed June 18, 1986 now abandoned which is a division of application Ser. No. 673,231 filed Nov. 19, 1984 now U.S. Pat. No. 4,611,068.
BACKGROUND OF THE INVENTION
Endo et al., J. Antibiotics, XXIX, 1346 (1976) described a fermentation product, ML-236B, with potent antihypercholesterolemic activity which acts by inhibiting HMG-CoA reductase. This material, named compactin by Brown et al., J. Chem. Soc., Perkin I, 1165 (1976) was shown to have a desmethyl mevalonolactone partial structure and the stereochemistry was studied.
Shortly thereafter a chemically similar, natural product MK-803 (mevinolin), obtained by fermentation, was isolated and characterized, by Monaghan et al., U.S. Pat. No. 4,231,938. It has been shown to have the same desmethyl mevalonolactone partial structure and the absolute stereochemical configuration has been determined and described in EPO publication No. 0,022,478 of Merck & Co., Inc.
Totally synthetic analogs of these natural inhibitors have been prepared and described in Sankyo's U.S. Pat. No. 4,198,425 and Sankyo's U.S. Pat. No. 4,255,444 with no attempt being made to separate the stereo- and optical isomers. Subsequently, as described in Merck's EPO publication No. 0,024,348 and by Meyer, Ann. Chem., (1979), pages 484-491, similar totally synthetic analogs were separated into their stereoisomers and optical enantiomers. Furthermore, it was shown in EPO publication No. 0,024,348 that essentially all of the HMG-CoA reductase activity resides in the 4(R)-trans species as is the case with the naturally occurring compounds compactin and mevinolin.
In most of the prior art process for preparing the totally synthetic compounds, the lactone moiety of each compound had to be elaborated by a lengthy series of synthetic operations followed by very tedious and expensive chromatographic separation of the cis, trans racemates, or enantiomers, following which, the inactive cis-isomer would be discarded.
A process for the preparation of the lactone ring system in the correct optically active form was recently reported by Majewski et al., Tetrahedron Lett., 1984, 2101-2104 utilizing a (3S,5S) iodoketal of the following formula: ##STR2##
DETAILED DESCRIPTION OF THE INVENTION
This invention relates to a novel process for the preparation of antihypercholesterolemic agents of the following general structural formula (I): ##STR3## wherein R 1 is selected from the group consisting of: ##STR4## wherein Q is ##STR5## or ##STR6## R 6 is H or OH;
R is hydrogen or methyl, and a, b, c, and d represent optional double bonds, especially wherein b and d represent double bonds or a, b, c, and d are all single bonds; or ##STR7## wherein R 2 and R 3 are independently C 1-3 alkyl or halo (F, Cl or Br) and R 4 is hydrogen, phenyl, benzyloxy, substituted phenyl or substituted benzyloxy in which the phenyl group in each case is substituted with one or more substituents selected from C 1-3 alkyl and halo, which comprises:
(A) reacting a compound of the formula (II): ##STR8## wherein R 5 is C 1-5 alkyl or benzyl and R 7 is C 1-5 alkyl, benzyl, C 2-5 alkoxyalkyl, such as CH 3 OCH 2 , or C 3-6 alkoxyalkoxy lkyl, such as CH 3 OCH 2 CH 2 OCH 2 , with a compound of the formula (III):
R.sup.1 X (III)
wherein R 1 is defined above, X is a metal atom or metal complex selected from Li, MgCl, MgBr, (CuMgCl) 1/2 or (CuMgBr) 1/2 or an alkali metal (Li, Na, or K) plus an aryl sulfonyl group selected from ##STR9## followed by the removal of the aryl sulfonyl group [Trost et al. Tetrahedron Lett., 1976, 3477] to afford a compound of the formula (IV): ##STR10##
(B) lactonizing the compound of the formula (IV) under standard acidic conditions to afford the compound of formula (V): ##STR11## and
(C) removing the R 7 group by suitable methods known in the art [T. Greene, Protective Groups In Organic Synthesis, John Wiley & Sons, 1981, pp 10-86] or with an organoboron halide to afford the compound of formula (I).
In a preferred embodiment, the compounds prepared by the process of this invention are those compounds of the formula (I) wherein R 1 is (a) and R 6 is hydrogen and R is hydrogen or methyl and b and d represent double bonds or a, b, c and d are single bonds.
In a second preferred embodiment, the compounds prepared by the process of this invention are those compounds of the formula (I) wherein R 1 is (b), R 2 and R 3 independently are chloro, fluoro or methyl and R 4 is hydrogen, 4-fluoro-3-methylphenyl or 4-fluorobenzyloxy. The most preferred compounds are those wherein (1) R 2 and R 3 are methyl and R 4 is 4-fluoro-3-methylphenyl; (2) R 2 and R 3 are methyl and R 4 is 4-fluorobenzyloxy; and (3) R 2 and R 3 are chloro and R 4 is hydrogen.
The reaction of the compound of the formula (II) with the compound of the formula (III) is conducted at a temperature between -78° and 0° C., preferably at -78° C. with warming to -20° C. for a period of from 1 to 12 hours, most preferably 1 hour at -78° C. and 1 hour at -23° C., in a inert solvent. Illustrative of such inert solvents are: ethers or thioethers or mixtures thereof, such as diethyl ether, tetrahydrofuran, dimethoxyethane, dimethylsulfide and the like.
The amounts of reactants that are employed in this reaction may vary between 0.1 and 1.0 equivalents of the compound of the formula (II) to each equivalent of the compound of the formula (III). However, 0.4 equivalents of the compound of the formula (II) is preferred. The compound of the formula (III) wherein X is (CuMgBr) 1/2 is a preferred reactant.
The lactonization of the compound of the formula (IV) is conducted at a temperature between 0° and 25° C., preferably at ambient temperature, for a period of from 1 to 12 hours, preferably 3 hours in an inert solvent with a catalytic amount of an acid. Illustrative of such inert solvents are: hydrocarbons, such as hexane, toluene, benzene, cyclohexane and the like; and ethers, such as, diethylether, tetrahydrofuran, dimethoxyethane and the like. Illustrative of such acids are organic acids, such as, p-toluenesulfonic, benzenesulfonic and the like and inorganic acids, such as, hydrochloric. The preferred acid utilized in the lactonization is p-toluenesulfonic acid.
The removal of the R 7 protecting group is conducted at a temperature between -78° and 0° C., preferably at -78° for a period from 1 to 12 hours, preferably 1 hour in an inert solvent in the presence of an organoboron halide. Illustrative of such inert solvents are: chlorinated hydrocarbons, such as, methylene chloride, chloroform, dichloroethane or low melting mixtures thereof and the like.
The organoboron halide reactant is represented by the following formula:
R.sup.8 R.sup.9 BY
wherein R 8 and R 9 independently are C 1-4 alkyl, phenyl or when taken together with the boron atom to which they are attached form a 5, 6 or 7 membered ring or a bicyclic ring and Y is chloro or bromo. The preferred organoboron halide is dimethylboron bromide. The amount of the organoboron halide utilized may vary between 1 and 10 equivalents for each equivalent of the compound of the formula (V), with 4 equivalents being preferred.
The starting materials are either known or readily prepared according to the synthetic pathways described below.
For compounds of the formula (III) wherein R 1 is (a) and X is a metal atom or metal complex, Tetrahedron Lett., pp. 1373-6 (1983) describes a procedure for preparing compounds which can be readily converted into the desired compounds of the formula (III) using standard reaction conditions. For compounds of the formula (III) wherein X is ##STR12## Tetrahedron Lett., pp. 1655-8 (1984) describes a procedure for preparing compounds which can be readily converted into the desired compounds of the formula (III) using standard conditions. The compounds of the formula (III) wherein R 1 is (b) are known in the art.
The compound of the formula (II) wherein R 5 and R 7 are described above are readily prepared according to the following synthetic pathway from (S)-malic acid: ##STR13##
(S)-Malic acid (1) is reduced under standard reduction conditions using BH 3 .THF and then ketalized with acetone to give compound (2). Compound (2) is subjected to Swern oxidation to yield compound (3), which, without isolation, is treated under Wittig conditions with Ph 3 PCHCO 2 R 5 to give Compound (4). Compound (4) is hydrolyzed under acid conditions and selectively protected to give Compound (5) wherein Pr is a protecting group selected from benzoyl, acetyl, triphenylsilyl or tert-butyldiphenylsilyl, preferably t-butyldiphenylsilyl. Compound (5) is 1 cyclized to Compounds (6) and (7) under basic conditions with concomitant migration of the Pr group. Compound (7) may be isomerized to the desired Compound (6) under basic conditions. Compound (6) is converted to Compound (8) using an organoboranhalide R 8 R 9 BY, preferably dimethylboron bromide. Compound (8) is treated with R 7 -halide to get Compound (9) which is treated with tetraalkylammonium fluoride oranalkalimetal alkoxide to afford the compound of formula (II).
The following Examples illustrate the present invention and as such are not to be considered as limiting the invention set forth in the claims appended hereto.
EXAMPLE 1
Step (a)
Preparation of (S)-1,2-O-Isopropylidenebutane-1,2,4-triol
To a cold (0° C.), well-stirred solution of (S)-malic acid (13.4 g, 100 mmol) in 300 ml dry tetrahydrofuran, under argon, was added dropwise (via capillary) a tetrahydrofuran solution of borane-THF complex (300 ml, 300 mmol) over a period of 3 hours. The cooling bath was removed and the resultant slurry was stirred at room temperature for 15 hours. The reaction mixture was then cooled to 0° C. and carefully treated with dry methanol (100 ml). After warming to room temperature, the solvent was evaporated. The residue was evaporated three times with dry methanol (100 ml each) to ensure complete methanolysis of the reduction intermediate. Brief drying (0.1 mm) gave 10.3 g of the crude triol.
This material was dissolved in acetone (300 ml) and a catalytic amount of p-TsOH.H 2 O (0.95 g, 5 mmol) added. After 12 hours at room temperature the reaction mixture was quenched with triethylamine (0.70 ml, 5 mmol) and concentrated. The resultant oil was dissolved in ether (400 ml) and washed with water (3×50 ml) and brine (50 ml) and dried over MgSO 4 . Concentration and bulb-to-bulb distillation of the residue (air-bath temperature 85°-95° C., 0.15 mm; lit. 1 55°-61° C., 0.05 mm) gave 11.7 g (80%) of the desired product. 1 H NMR (CDCl 3 ) analysis showed that this material contained <10% of the isomeric acetonide (S)-2,4-O-isopropylidene butane-1,2,4-triol 1 ,2 and was used without further purification. This material exhibited IR (film) 3450, 2950, 1380 and 1050 cm -1 ; 1 H NMR (250 MHz, CDCl 3 ) δ1.38 (s, 3H), 1.43 (s, 3H), 1.79-1.88 (m, 2H), 2.55 (broad s, 1H), 3.61 (d,d, J=7.7 Hz, 1H), 3.80 (t, J-5.9 Hz, 2H), 4.10 (d,d J=7.0, 7.7 Hz, 1H), 4.28 (m, 1H).
Step (b)
Preparation of Ethyl (E)-(S)-O-Isopropylidene-5,6-dihydroxy-2-hexenoate
A cold (-78° C.) stirred solution of oxalyl chloride (1.92 ml, 22 mmol) in 50 ml of dry methylene chloride, under argon, was treated with a solution of DMSO (3.55 ml, 25 mmol) in the same solvent (10 ml). After stirring at -78° C. for 10 minutes a solution of (S)-1,2-O-isopropylidene butane-1,2,4-triol (2.92 g, 20 mmol) in 15 ml of methylene chloride was added. The resultant slurry was stirred at -78° C. for 40 minutes, then treated with diisopropylethylamine (17.5 ml, 100 mmol). The cooling bath was removed and the reaction mixture was stirred at room temperature for 1 hour to afford a yellow solution of (S)-O-isopropylidene 4-oxy-butane-1,2-diol.
This solution was cooled to 0° C. and treated with carbethoxymethylenetriphenylphosphorane (17.4 g, 50 mmol) at 0° C. for 1 hour and at room temperature for 4 hours. The resultant solution was diluted with ether (300 ml), washed with water (3×50 ml), 10% aqueous NaHSO 4 (50 ml) and brine (2×50 ml) and dried over MgSO 4 . Removal of solvent gave a viscous oil. Ether (150 ml) and hexane (150 ml) were added and the mixture kept at -10° C. for 15 hours. Filtration of the white precipitate (Ph 3 P=O) and removal of solvent gave the crude product. Flash chromatography (hexane-ethyl acetate 85:15) gave 3.60 g (84%) of ethyl (E)-(S)-O-isopropylidene-5,6-dihydroxy-2-hexenoate: [α] D -18.0 (c 2.43, MeOH); IR (film) 2994, 1727, 1661, 1372, 1269, 1172 and 1064 cm -1 ; 1 H NMR (CDCl 3 ) δ1.30 (t, J=7.0 Hz, 3H), 1.36 (s, 3H), 1.43 (s, 3H), 2.39-2.60 (m, 2H), 3.59 (m, 1H), 4.07 (m, 1H), 4.16-4.30 (buried m, 1H), 4.20 (q, J=7.0 Hz, 2H), 5.92 (d,t, J=15.5, 1.5 Hz, 1H), 6.92 (d,t, J=15.5, 7.2 Hz); MS m/e (relative intensity) 199 (43), 101 (100).
Anal. calcd. for C 11 H 18 O 4 : C, 61.66; H, 8.47. Found: C, 61.42; H, 8.44.
Step (c)
Preparation of Ethyl (E)-(S)-5,6-dihydroxy-2-hexenoate
To a solution of ethyl-(E)-(S)-O-isopropylidene-5,6-dihydroxy-2-hexenoate (5.35 g, 25 mmol) in 100 ml tetrahydrofuran was added 1N HCl (66 ml). The reaction mixture was stirred at room temperature for 18 hours. NaCl (10 g) and ethyl acetate (400 ml) were added. The organic layer was separated and washed with brine (2×50 ml). The aqueous washings were extracted with ethyl acetate (2×100 ml), the extracts washed with brine (25 ml) and the organic layers combined. Drying (MgSO 4 ) and removal of solvent gave 4.04 g (93%) of a viscous oil. This material exhibited: IR (film) 3400, 1720, 1657 and 1040 cm -1 ; 1 H NMR (CDCl 3 ) δ1.28 (t, J=7.0 Hz, 3H), 2.25 (broad s, 1H), 2.39 (m, 2H), 2.58 (broad s, 1H), 3.43-3.55 (m, 1H), 3.63-3.73 (m, 1H), 3.81-3.92 (m, 1H), 4.18 (q, J=7.0 Hz, 2H), 5.91 (d, J=16 Hz, 1H), 6.96 (dt, J=16, 6.6 Hz, 1H).
Anal. calcd. for C 8 H 14 O 4 : C, 55.16; H, 8.10. Found: C, 55.52; H, 8.08.
Step (d)
Preparation of Ethyl (E)-(S)-6-t-butyldiphenylsiloxy-5-hydroxy-2-hexenoate
To a cold (0° C.), stirred solution of the diol from Step (c) (4.04 g, 23.2 mmol) in 116 ml dry methylene chloride, under argon, was sequentially added diisopropylethylamine (6.08 ml, 34.8 mmol) 4-dimethylamino pyridine (280 mg, 2.3 mmol) and t-butyldiphenylsilyl chloride (7.54 ml, 29 mmol). The reaction mixture was stirred at 0° C. for 1 hour and then at room temperature for 18 hours. Water (100 ml) and ether (400 ml) were added. The organic layer was separated, washed with water (100 ml), saturated aqueous NaHCO 3 (50 ml), 10% aqueous NaHSO 4 (50 ml), and brine (50 ml). Drying (MgSO 4 ) and removal of solvent gave the crude product. Purification by flash chromatography (300 g, SiO 2 , hexane-ethyl acetate 85:15) gave 9.41 g (98%) of essentially pure mono-siloxy alcohol. This material exhibited: [α] D -10.0 (c 1.23, MeOH); IR (film) 3480, 2940, 1723, 1658, 1594, 1431, 1114 and 704 cm -1 ; 1 H NMR (CDCl 3 ) δ1.07 (s, 9H), 1.28 (t, J=7.2 Hz, 3H), 2.36 (broad t, J=6.5 Hz, 2H), 2.53 (d, J=4.4 Hz, 1H), 3.53 (d,d, J=10.2, 6.7 Hz, 1H), 3.67 (d,d, J=10.2, 3.7 Hz, 1H), 3.85 (m, 1H), 4.18 (q, J=7.2 Hz, 2H), 5.87 (d, J=15.5 Hz, 1H), 6.94 (d,d, J=15.5, 7.3 Hz, 1H), 7.34-7.49 (m, 6H), 7.60-7.68 (m, 4H); MS m/e (relative intensity) 355 (5), 199 (100).
Anal. calcd. for C 24 H 34 O 4 Si: C, 69.87; H, 7.82. Found: C, 70.22; H, 7.60.
Step (e)
Preparation of Ethyl 2(R)-(4(S)-tert-butyldiphenylsiloxytetrahydrofuran)acetate and its 2(S),4(S)-isomer
To a cold (0° C.), stirred solution of ethyl (E)-(S)-6-tert-butyldiphenylsiloxy-(5)-hydroxy-2-hexenoate (9.41 g, 23.0 mmol) in 200 ml dry ethanol, under argon, was added a solution of sodium ethoxide (2.3 mmol) in ethanol (30 ml). Stirring was continued at room temperature for 2 hours and at 65° C. for 4 hours. The reaction mixture was then cooled to room temperature and quenched with acetic acid (2.3 mmol). Concentration provided the crude product as a yellow oil (9.5 g). TLC (hexane-ethyl acetate, 4:1) and 1 H NMR (250 MHz, CDCl 3 ) analyses of the crude product indicated the pressure of the desired β (R f 0.55) and α (R f 0.53) product isomers in a ratio of 2:1 along with a small amount of starting material. This material was purified in two batches by careful flash chromatography (300 g SiO 2 , eluant:hexane-ethyl acetate, 95:5) to afford after concentration of the appropriate fractions 4.51 g of pure 2(R),4(S)-β-isomer.
Further elution of the colunn (hexane-ethyl acetate, 4:1) and combination of the appropriate fractions gave 4.80 g of a mixture of the 2(R),4(S)- and 2(S),4(S)-isomers along with a small amount of starting material. This material was dissolved in ethanol (160 ml) and resubjected to the equilibration conditions (1.16 mmol NaOEt) at 65° C. for 5 hours. Work-up and purification as outlined above (300 g SiO 2 , eluant:hexane-ethyl acetate, 95:5 then 4:1) gave 2.27 g of pure 2(R),4(S)-β-isomer (total yield 6.77 g, 72%). [α] D 7.81 (c 2.08, MeOH), IR (film) 3080, 2940, 1738, 1593, 1115 and 703 cm -1 ; 1 H NMR (250 MHz, CDCl 3 ) δ1.06 (s, 9H), 1.26 (t, J=7.2 Hz, 1H), 1.55 (d,d,d, J=15.4, 9.6, 5.6 Hz, 1H), 2.07 (d,d,d, J=15.4, 5.6, 1.8 Hz, 1H), 2.44 (d,d, J=15.4, 5.9 Hz, 1H), 2.57 (d,d, J=15.2, 7.2 Hz, 1H), 3.72 (d,d,d, J=9.4, 2.6, 0.8 Hz, 1H), 3.84 (d,d, J=9.4, 4.6 Hz, 1H), 4.15 (q, J=7.2 Hz, 2H), 4.45 (m, 1H), 4.57 (m, 1H), 7.33-7.50 (m, 6H), 7.60-7.76 (m, 4H); MS m/e (relative intensity) 355 (11), 199 (100).
Anal. calcd. for C 24 H 32 O 4 Si: C, 69.87; H, 7.82. Found: C, 70.15; H, 7.73.
Further elution of the column (hexane-ethyl acetate, 4:1) collection of the appropriate fractions gave 0.98 g (10%) of the 2(S),4(S)-α-isomer. IR (film) 3081, 2942, 1738, 1593, 1113 and 705 cm -1 ; 1 H NMR (250 MHz, CDCl 3 ) δ1.07 (s, 9H), 1.27 (t, J=7.2 Hz, 3H), 1.75 (d,d,d,d, J=13.1, 5.7, 3.4, 0.9 Hz, 1H), 2.16 (d,d,d, J=13.1, 7.5, 6.3 Hz, 1H), 2.66 (d,d, J=15.4, 6.4 Hz, 1H), 2.84 (d,d, J=15.4, 7.3 Hz, 1H), 3.62 (d,d, J=9.4, 4.9 Hz, 1H), 3.81 (d,d,d, J=9.4, 2.8, 0.9 Hz, 1H), 4.16 (q, J=7.2 Hz, 2H), 4.31 (m, 1H), 4.43 (m, 1H), 7.33-7.50 (m, 6H), 7.62-7.77 (m, 4H); MS m/e (relative intensity) 367 (14), 355 (100), 199 (61).
Step (f)
Preparation of Ethyl 6-bromo-5(S)-tertbutyldiphenylsiloxy-3(R)-hydroxyhexanoate
To a cold (0° C.), stirred mixture of ethyl 2(R)-(4(S)-tert-butyldiphenylsiloxytetrahydrofuran)acetate (1.21 g, 2.93 mmol) and diisopropylethylamine (51 μl, 0.29 mmol) in 16.5 l ml dry methylene chloride, under argon, was added a solution of dimethylboron bromide (3.46 ml, 5.98 mmol) in methylene chloride. The reaction mixture was then stirred at room temperature for 2 hours, diluted with ether (100 ml) and quenched with saturated aqueous NaHCO 3 (10 ml). The organic layer was separated, washed with 10 ml portions of saturated aqueous NaHCO 3 , water and brine and dried over MgSO 4 . Removal of solvent gave a yellow oil which was subjected to flash chromatography on silica gel (eluant:hexane-ethyl acetate, 4:1) to afford 1.19 g (82%) of the purified product as a colorless oil. This material exhibited [α] D +2.81 (c 1.67, MeOH); IR (film) 3430, 2938, 1725, 1590, 1430, 1112 and 700 cm -1 ; 1 H NMR (250 MHz, CDCl 3 ) δ1.08 (s, 9H), 1.26 (t, J=7.2 Hz, 3H), 1.82 (m, 2H), 2.30 (m, 2H), 3.05 (broad s, 1H), 3.39 (d, J=3.7 Hz, 2H), 4.10 (m, 1H), 4.15 (q, J=7.2 Hz, 2H), 7.34-7.48 (m, 6H), 7.64-7.70 (m, 4H); MS m/e (relative intensity) 447 (4), 435 (2), 199 (100).
Anal. calcd. for C 24 H 33 O 4 SiBr: C, 58.41; H, 6.74. Found: C, 58.19; H, 6.73.
Step (g)
Preparation of Ethyl 6-bromo-5(S)-tert-butyldiphenylsiloxy-(3)-(R)-(methoxymethoxy)hexanoate
To a cold (-10° C.), stirred solution of ethyl 6-bromo-5(S)-tert-butyldiphenylsiloxy-(3)-(R)-hydroxyhexanoate (0.84 g, 1.70 mmol) in 5.15 ml of dry acetonitrile, under argon, were sequentially added diisopropylethylamine (0.89 ml, 5.10 mmol), 4-N,N-dimethylaminopyridine (21 mg, 0.17 mmol) and chloromethyl methyl ether (1.03 ml, 13.6 mmol). The argon inlet was removed and the reaction mixture was stored at -3° C. for 24 hours. The reaction mixture was then quenched with saturated (aqueous) NaHCO 3 (3 ml) and diluted with ether (60 ml). The organic layer was separated, washed with saturated aqueous NaHCO 3 (2×10 ml), water (10 ml), 10% aqueous NaHSO 4 (10 ml) water (10 ml) and brine (10 ml). Drying (MgSO 4 ) and concentration gave a pale yellow oil. Purification by flash chromatography on silica gel (60 g, eluant:hexane-ethyl acetate, 4:1) provided 0.85 g (94%) of pure product. This material exhibited: [α] D =0.77 (c 1.68, CHCl 3 ): IR (film) 3075, 2935, 1738, 1589, 1428, 1031 and 701 cm -1 ; 1 H NMR (250 MHz, CDCl 3 ) δ1.08 (s, 9H), 1.24 (t, J=7.1 Hz, 3H), 1.94 (broad t, J=6.0 Hz, 2H), 2.26 (d,d, J=15.3, 5.2 Hz, 1H), 2.39 (d,d, J=15.3, 7.3 Hz, 1H), 3.18 (s, 3H), 3.37 (d, J=4.3 Hz, 2H), 3.92 (m, 1H), 4.04 (m, 1H), 4.12 (q, J=7.1 Hz, 2H), 4.50 (d, J=7.1 Hz, A part of AB, 1H), 4.58 (d, J=7.1 Hz, B part of AB, 1H), 7.33-7.46 (m, 6H), 7.65-7.74 (m, 4H); MS m/e (relative intensity) 479 (28), 213 (100).
Anal. calcd. for C 26 H 37 O 5 SiBr: C, 58.09; H, 6.97; Br, 14.86. Found: C, 58.33; H, 7.02; Br, 14.79.
Step (h)
Preparation of Ethyl 5(S),6-epoxy-3(R)-(methoxymethoxy)hexanoate
A cold (0° C.), stirred solution of ethyl 6-bromo-5(S)-tert-butyldiphenylsiloxy-3(R)-(methoxymethoxy)hexanoate (0.80 g, 1.49 mmol) in 3.8 ml dry tetrahydrofuran (THF), under argon, was treated with a solution of tetra-n-butylammonium fluoride (4.47 ml, 4.47 l mmol; 1.0M solution in THF). The cooling bath was removed and the reaction mixture was stirred at room temperature for 3 hours. Ether (50 ml) was then added and the mixture washed with water (5 ml), 10% aqueous NaHSO 4 (5 ml), water (5 ml) and brine (5 ml). Drying (MgSO 4 ) and removal of solvent gave a pale yellow oil which was subjected to flash chromatography on silica gel (20 g, hexane-ethyl acetate, 4:1) to provide 0.241 g (74%) of the desired epoxide, [α] D 31.5 (c 0.98, MeOH). IR (film) 2938, 1736 and 1035 cm -1 ; 1 H NMR (250 MHz, CDCl 3 ) α1.23 (t, J=7.2 Hz, 3H), 1.70-1.82 (m, 1H), 1.86-1.99 (m, 1H), 2.49 (m, 1H), 2.56 (d,d, J=15.6, 5.0 Hz, 1H), 2.71 (d,d, J=15.6, 6.0 Hz, 1H), 2.77 (m, 1H), 3.08 (m, 1H), 3.38 (s, 3H), 4.16 (q, J=7.2 Hz, 2H), 4.29 (m, 1H), 4.67 (d, A part of AB, J=7.8 Hz, 1H), 4.72 (d, B part of AB, J=7.8 Hz, 1H).
Anal. calcd. for C 10 H 18 O 5 : C, 55.03; H, 8.31. Found: C, 54.82; H, 8.39.
EXAMPLE 2
Step (a)
Preparation of 2,4-Dichlorobenzylmagesium bromide
To stirred magnesium metal (0.121 g, 5 mmol) in 1.0 ml of dry ether, under argon, was added 0.5 ml of an ether solution of 2,4-dichlorobenzyl bromide (1.20 g, 5 mmol in 4.0 ml dry ether). A small crystal of iodine was added and initiation of the reaction took place (exothermic) within 5 minutes. The remaining solution of 2,4-dichlorobenzyl bromide was then added dropwise at such a rate as to maintain a mild reflux. After the addition was complete the reaction mixture was refluxed for 1 hour to afford a colorless solution of 2,4-dichlorobenzylmagnesium bromide in ether (about 1.0M).
Step (b)
Preparation of Ethyl 7-(2,4-dichlorophenyl-5(R)-hydroxy-3(R)-(methoxymethoxy)heptanoate
To a cold (-78° C.), stirred suspension of cuprous bromide-dimethyl sulfide complex (88 mg. 0.43 mmol) in a mixture of dimethyl sulfide (1.3 ml) and ether (0.4 ml), under argon, was added dropwise a solution of 2,4-dichlorobenzylmagnesium bromide (0.88 ml, 0.88 mmol; 1.0M in ether). The resultant orange solution was stirred at -78° C. for 15 minutes. A solution of ethyl 5(S),6-epoxy-3(R)-(methoxymethoxy)hexanoate (72 mg, 0.33 mmol) in 0.5 ml dry ether was then added dropwise over a period of 3 minutes. The reaction mixture was stirred at -78° C. for 1 hour and at -23° C. for 1 hour. Saturated aqueous NH 4 Cl (0.5 ml) adjusted to pH 8 with concentrated NH 4 OH, and ether (20 ml) were added. After warming to room temperature the organic layer was separated, washed with 5 ml portions of saturated aqueous NH 4 Cl (pH 8), water and brine and dried over MgSO 4 . Concentration and purification by flash chromatography on silica gel (eluant:hexane-ethyl acetate, 7:3) gave pure product, 124 mg (100%). This material exhibited: [α] D +5.37 (c 0.85, MeOH); IR (film) 3480, 2943, 1738, 1591, 1477 and 1136 cm -1 ; 1 H NMR (250 MHz, CDCl 3 ) δ1.26 (t, J=7.2 Hz, 3H), 1.66-1.87 (m, 4H), 2.50 (d,d, J=15.0, 6.4 Hz, 1H), 2.71 (d,d, J=15.0, 6.3 Hz, 1H), 2.74-2.96 (m, 2H), 3.11 (broad s, 1H), 3.39 (s, 3H), 3.80 (m, 1H), 4.14 (q, J=7.2 Hz, 2H), 4.22 (m, 1H), 4.69 (d, A part of AB, J=6.7 Hz, 1H), 4.75 (d, B part of AB, J=6.7 Hz), 7.18 (m, 2H), 7.34 (m, 1H); MS m/e (relative intensity) 159 (100).
Anal. calcd. for C 17 H 24 O 5 Cl 2 : C, 53.84; H, 6.38. Found: C, 53.91; H, 6.50.
Step (c)
Preparation of 6(R)-[2-(2,4-dichlorophenyl)ethyl]-4(R)-(methoxymethoxy)tetrahydro-2H-pyran-2-one
A mixture of 7-(2,4-dichlorophenyl)-5(R)-hydroxy-3(R)-(methoxymethoxy)heptanoate (100 mg, 0.26 mmol) and p-TsOH.H 2 O (5 mg, 0.026 mmol) in 1.30 ml benzene, under argon, was stirred at room temperature for 3 hours. The reaction mixture was then diluted with either (20 ml), washed with 2 ml portions of saturated aqueous NaHCO 3 , water and brine and dried over MgSO 4 . Concentration and purification of the residue by flash chromatography (eluant:hexane-ethyl acetate, 4:1) afforded 78 mg (90%) of the desired lactone, [α] D +32.4 (c 0.71, MeOH). IR (film) 2940, 1740, 1590, 1475 and 1040 cm -1 ; 1 H NMR (250 MHz, CDCl 3 ) δ1.75 (m, 1H), 1.94 (m, 2H), 2.07 (m, 1H), 2.65-3.05 (m, 4H), 3.35 (s, 3H), 4.20 (m, 1H), 4.63 (m, 1H), 4.67 (s, 2H), 7.19 (s, 2H), 7.37 (s, 1H); MS m/e (relative intensity) 332 (13), 159 (100).
Step (d)
Preparation of 6(R)-[2-(2,4-dichlorophenyl)ethyl]-4(R)-hydroxy-tetrahydro-2H-pyran-2-one
To a cold (-78° C.), stirred solution of the corresponding methoxymethyl ether derivative from Step (c) (65 mg, 0.20 mmol) in 1.50 ml dry methylene chloride, under argon, was added a solution of dimethylboron bromide (1.56M) (0.51 ml, 0.80 mmol) in methylene chloride. Stirring was continued at -78° C. for 1 hour. The reaction mixture was then added to a room temperature stirred mixture of tetrahydrofuran (2.0 ml) and saturated aqueous NaHCO 3 (2 ml). After 3 minutes ether (20 ml) was added and the organic layer washed with 2 ml portions of saturated aqueous NaHCO 3 , water and brine. Drying (MgSO 4 ) and concentration gave the crude product. Purification by flash chromatography (6 g, SiO 2 , eluant:hexane-ethyl acetate, 4:1) gave 46 mg (79%) of the desired product, [α] D +59.7 (c 1.10, CHCl 3 ). IR (film) 3440, 1728, 1476, 1260 and 1050 cm -1 ; 1 H NMR (250 MHz, CDCl 3 ) δ1.78 (m, 1H), 1.88-2.10 (m, 3H), 2.20 (d, J=3.6 Hz, 1H), 2.64 (d,d,d, J=16, 3.4, 0.9 Hz, 1H), 2.76 (d,d, J=16, 4 Hz, 1H), 2.77-3.05 (m, 2H), 4.41 (broad m, 1H), 4.71 (broad m, 1H), 7.18 (s, 2H), 7.36 (s, 1H); MS m/e (relative intensity) 288 (15), 159 (100).
Anal. calcd. for C 13 H 14 O 3 Cl 2 : C, 54.00; H, 4.88. Found: C, 54.02; H, 4.89.
EXAMPLES 3-12
Utilizing the general procedures of Example 2 and starting from the appropriately substituted compounds of the formula (III) and ethyl 5(S),6-epoxy-3(R)-(methoxymethoxy)hexanoate the following compounds of the formula (I) are prepared:
______________________________________CompoundNumber R.sup.1______________________________________ ##STR14##4 ##STR15##5 ##STR16##6 ##STR17##7 ##STR18##8 ##STR19##9 ##STR20##10 ##STR21##11 ##STR22##12 ##STR23##______________________________________ | An intermediate compound of the formula ##STR1## wherein Y is chloro or bromo: Pr is a protecting group selected from benzoyl, acetyl, triphenylsilyl or t-butyldiphenylsilyl:
R 5 is C 1-5 alkyl or benzyl; and
R 7 is C 1-5 alkyl, benzyl, C 2-5 alkoxyalkyl or C 3-5 alkoxyalkoxyalkyl,
useful for the preparation of certain HMG-CoA reductase inhibitors. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a fastening particularly usable in skis.
The known ski fastenings are constituted by a heel element and by a tip element, both associated with the ski, in order to allow the engagement of the usually standardized ends of a ski boot.
Said heel element and said tip element therefore have adapted and separate adjustment means for the correct engagement, disengagement and securing of the boot.
This solution, however, forces the skier to perform separate operations in order to optimally adjust the heel element and the tip element.
As a partial solution to this disadvantage, an Austrian patent Application No. 2622/81, filed on Jun. 12, 1981, discloses a fastening which comprises a front engagement element and a rear engagement element as well as adjustment means interposed therebetween.
Even this solution, however, has disadvantages: first of all said adjustment means are subjected to considerable stress, which leads to their rapid wear; secondly, said adjustment means, instead of varying the degree of securing of the tip element and of the heel element at the end of the boot, substantially allow to adjust the distance between the heel element and the tip element according to the size of the boot.
Finally, it should be noted that the stiff elements, such as rods, used for connecting the adjustment means with the supports for the heel element and the tip element, stiffen the ski and limit its flexibility.
SUMMARY OF THE INVENTION
The aim of the present invention is therefore to eliminate the disadvantages described above in known types by providing a fastening which allows the skier to simultaneously achieve, with a single operation, an optimum adjustment of both the front and rear engagement means.
Within the scope of the above described aim, an important object is to provide a ski fastening having components whereof are not subjected to heavy stresses during the adjustments made thereto.
Another important object is to provide a ski fastening which allows to maintain the relative distance between the front and rear engagement means during the inflections to which the ski is subjected during its use.
Not least object is to provide a ski fastening which is reliable and safe in use.
This aim, these objects and others which will become apparent hereinafter are achieved by a fastening, particularly for skis, which includes a front engagement means for engaging a ski boot toe portion and a rear engagement means for engaging a ski boot heel portion, said front and rear engagement means both being mountable on a ski top portion which defines a separated distance therebetween, said rear engagement means comprising a pivoting heel locking element and a first adjustable biasing means for providing a first adjustable locking force acting on said pivoting heel locking element, said front engagement means comprising a pivoting tip locking element and a second adjustable biasing means for providing a second adjustable locking force acting on said pivoting tip locking element, said first adjustable biasing means comprising a first spring means and said second adjustable biasing means comprising a second spring means, wherein said rear engagement means comprises means for housing both of said first spring means and said second spring means, and wherein the fastening further comprises means for simultaneously adjusting both said first and second adjustable locking forces. Advantageously, the means for housing both of said first spring means and said second spring means comprises a first body connectable at an adjustable position to the ski and a second body which is slidably supported with respect to the first body against the action of spring biasing means along a direction which parallel to the longitudinal direction of the ski to thereby maintain a constant distance between the front and rear engagement means even upon flexing of the ski.
BRIEF DESCRIPTION OF THE DRAWINGS
Further characteristics and advantages of the invention will become apparent from the detailed description of two particular but not exclusive embodiments, illustrated only by way of non-limitative example in the accompanying drawings, wherein:
FIG. 1 is a sectional view of the front engagement means, taken along a longitudinal median axis;
FIG. 2 is a view, similar to the preceding one, of the rear engagement means;
FIG. 3 is a view taken along a sectional plane III--III of FIG. 1;
FIG. 4 is a view taken along the sectional plane IV--IV of FIG. 2;
FIG. 5 is an exploded view of some of the components of the rear engagement means;
FIGS. 6 and 7 are views of other details present at the rear engagement means;
FIG. 8 is a view, similar to that of FIG. 2, of a second embodiment for the rear engagement means;
FIG. 9 is a view taken along the sectional plane IX--IX of FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the above figures, the ski fastening, according to the present invention, comprises a rear engagement means 2 and a front engagement means 3.
The rear engagement means 2 is constituted by a first body 4 which is associated with a ski 5 and by a second body 6 which is slidable with respect to the first body 4.
The rear engagement means can be made to slide with respect to the ski 5, for example in order to adjust the interspace between the rear engagement means and the front engagement means; during said sliding, the first body 4 and the second body 6 rigidly move together, relatively to the ski 5.
This sliding is allowed by a first screw 7 having a stem which interacts with a complementarily threaded support 8. The support 8 is rigidly coupled to, and protrudes from, a rear plate 9a, which is rigidly associated with the ski 5. A front plate 9b is frontally provided on the same axis as the plate 9a and is also rigidly associated with the ski 5. A U-shaped profiled element 10 is pivoted thereto centrally to the base, and a tip element 11, which constitutes the front engagement means 3, is pivoted between the wings of said U-shaped profiled element 10 along an axis which is transverse to the ski 5.
The first screw 7 has an end which can be accessed from the outside of the rear engagement means 2 in order to activate it by means of adapted tools such as for example a screwdriver; its other end, indicated by the numeral 12, has a perimetric tang 13 and a first axial seat with a polygonal shape, indicated by the numeral 14.
On one side, the perimetric tang 13 slides axially to the ski within an adapted second seat 15 which is defined longitudinally at the rear plate 9a; at the other side it is coupled to the first body 4 at a first groove 16 which is defined thereon.
The first body 4 is accommodated within a first cavity 17 internally provided in the second body 6.
The sliding of the second body 6 with respect to the first body 4, and therefore with respect to the ski, occurs in contrast with a pair of first springs 18a and 18b which are interposed between a pair of first tabs 19a and 19b which protrude laterally to the first body 4 and a pair of second tabs 20a and 20b which face the preceding ones and protrude internally to the second body 6 toward the adjacent first body 4.
The rear engagement means furthermore comprises a lever 21 which is pivoted transversely proximate to the end of the second body 6 which faces the front engagement means 3; said lever comprises at its lower end a heel locking element for releasably engaging and holding down the heel 22 of a ski boot.
A cam 23 furthermore protrudes axially at the end of the second body 6 to which the lever 21 is pivoted, and interacts with the lever 21 in contrast with a first elastically deformable element constituted by a first spring 24.
Said spring has an end which interacts with the corresponding end of the cam 23 and which is internal to the first cavity 17 of the second body 6; the other end of the spring 24 is accommodated within a third cylindrical seat 25 which is defined axially to a polygonal element 26 which is associated with the end of a second screw 27 which can be accessed from the outside of the second body 6 and which engages therewith at a threaded seat 6a defined thereon.
As will become clear hereinafter, the second screw 27 forms part of the means for simultaneously adjusting both of the locking forces for holding down the ski boot provided by the front and rear engagement means.
A first cylinder 28 is associated externally and coaxially to the polygonal element 26, is internally shaped complementarily to said polygonal element and is externally threaded so as to engage a complementarily shaped thread defined at a fourth cylindrical seat 29 which is defined axially to the first body 4 at a third tab 30 which protrudes therefrom from the end adjacent to the support 8.
The end of a second elastically deformable element, such as a second spring 31, is accommodated within the fourth seat 29 and abuts at the end of the first cylinder 28.
Said second spring 31 is arranged coaxially and externally to the first spring 24 and interacts with the surface of a second cylinder 32 which is arranged adjacent and coaxial to the end of the cam 23 which is internal to the first cavity 17.
First pins, indicated by the numerals 33a and 33b, protrude diametrically to the second cylinder 32 along a plane which is transverse to the ski 5.
The end of a first pair of rockers 34a and 34b is connected to the first pins; said rockers are preferably centrally pivoted transversely to the first body 4 and are connected, at their other end, to a pair of second pins 35a and 35b.
Said second pins protrude longitudinally to a block 36 which is arranged transversely and below the first body 4 at an adapted second cavity 37 defined thereon.
An internally threaded seat for a complementarily threaded third screw 38 is defined transversely to the block 36; one of the ends of said screw, which are indicated by the numerals 39a and 39b, is shaped complementarily to, and accommodated at, the first seat 14 defined at the end of the first screw 7, and the other one is mushroom-shaped.
The mushroom-shaped end 39b is associated in a complementarily shaped seat defined at the end of a rod 40 which is slidable above the front plate 9b and the rear plate 9a.
The rod 40 extends on said plates until it is proximate to the profile 10; a third pin 41 protrudes thereat and is accommodated in a third cavity 42 provided on the tip element 11.
The third pin 41 has a fourth tab 43 which is at an angle with respect to the plane of arrangement of the ski so as to form an acute angle in the direction of the tip of said ski, which assumes, in the region directed toward the rear engagement means, a triangular configuration with a rounded vertex.
The third cavity 42 assumes a similar configuration at the fourth tab 43.
The use of the ski fastening is as follows: initially, in order to adjust the release load, a rotation is imparted to the second screw 27 by means of adapted tools.
Said screw 27 compresses the first spring 24 and the first cylinder 28 is simultaneously moved, by virtue of the coupling between the polygonal element 26 and said first cylinder 28, concordantly with the movement of the screw 27, which compresses the second spring 31.
The pitches of the threads of the second screw 27 and of the cylinder 28 may be identical or different from one another; in the latter case, part of the ratio occurring between the first spring 24 and the second spring 31 can be obtained by varying the pitches of the two threads.
The action of the first spring 24 contrasts the rotation of the lever 21 by means of the cam 23 and therefore the release of the heel element.
The second spring 31 instead opposes the translatory motion of the second cylinder 32 which is imparted by the movement of the tip element in the manner described hereafter.
If the release of the tip element in limit conditions is to be achieved, the third pin 41 has the function of subjecting the rod 40 to traction and of then sliding it forward with respect to the ski consequent to a rotation of the tip element 11 on the vertical plane or on the horizontal plane.
The translatory motion of the rod 40 and consequently of the third screw 38 with respect to the first screw 7 moves forward the block 36 and thus the pair of second pins 35a and 35b, thereby rotating the rockers 34a and 34b around the axis of pivoting to the first body 4.
The end of the rockers which engage the first pins 33a and 33b therefore oscillates backward, moving the second cylinder 32 to compress the second spring 31.
Once the reaction or locking force provided by the spring, which is equal to the set limit load, is overcome, the tip element will rotate to thereby release the boot.
If the fastening is to be adapted to the length of the sole, a rotation imparted to the first screw 7 is followed by the backward movement of the assembly of elements formed by the first body 4 and by the second body 6 with respect to the tip element 11.
The motion transmitted to the third screw 38 ensures the backward motion of the block 36 with respect to said third screw and therefore of the second pins 35a and 35b in order to ensure the vertical alignment of the first pins 33a and 33b with the second pins 35a and 35b so as to maintain the neutral position for the rockers 34a and 34b.
It is finally possible to maintain the relative distance between the rear and front engagement means during the inflection of the ski in use by virtue of the sliding of the second body 6 with respect to the first body 4 in contrast with the first springs 18a and 18b.
The relative mutual translatory motion is also imparted between the second screw 27 and the first cylinder 28 by virtue of their mutual polygonal coupling.
This allows to keep unchanged the degree of compression of the first and second springs: the first spring 24 is fact moves rigidly with the second body 6 and with the second screw 27, whereas the second spring 31 remains in fixed position with respect to the first body 4, the first cylinder 28 and the second cylinder 32.
It has thus been observed that the invention has achieved the intended aim and objects, a fastening having been provided which has adjustments which are centralized in a single seat and which can both be actuated simultaneously by means of a single operation.
Adjustments of the locking forces provided by the two engagement means are thus achieved in which there is the assurance that the degree of setting selected for the two engagement means is the same or less than the ratio between the elastic constants of the springs.
Said ratio is, according to the currently applicable laws, constant with good approximation.
This allows, by accommodating the first spring 24 and the second spring 31, which meet the above mentioned requirement, within the first cavity 17, to compress both of them by means of the first screw 27.
It is therefore possible to perform a single manual operation for the simultaneous adjustment of the front and rear engagement means, said adjustments being adequate to the load requirements of said means, thus complying with the currently applicable laws.
Furthermore there is the assurance that the setting selected for the engagement means is the same or less than the ratio between the first spring and the second spring.
Finally, the fastening also has small dimentions.
The invention is naturally susceptible to numerous modifications and variations, all of which are within the scope of the same inventive concept.
FIGS. 8 and 9 illustrate a second embodiment for a ski fastening in which specifically the rear engagement means 102 is again composed of a first body 104 which is fixed with respect to the ski 105 and by a second body 106 which is slidable with respect to the first body.
The second body 106 again has a box-like structure inside which a pair of first cavities 117a and 117b is defined; said cavities are partially mutually divided by a partition 144 which is arranged approximately parallel to the plane of the ski 105 and is slightly higher than the first body 104 so as to be able to contain said body.
A first screw 107 is arranged longitudinally to the ski at the first lower cavity 117b and has a head 145 which protrudes rearward to both the first body 104 and the second body 106; the other end is threaded and engages at a complementarily threaded seat 106a defined on the second body 106.
The rotation of the first screw 107 therefore allows to adapt the fastening to the length of the sole since a translatory motion of the second body 106 with respect to the ski 105 is forced.
A first spring 124 is arranged coaxially to the stem of the first screw 107 and abuts at one end with the rear wall 146 of the first body 104 and, at the other end, with a first cylinder 128 which is keyed to the first screw 107.
The purpose of the first spring 124 is to contrast the sliding of the second body 106 with respect to the first body 104 during the inflection of the ski, to recover the elastic plays.
The release load is adjusted by means of a second screw 127 which is rotatably associated with, and rearwardly protrudes from, the second body 106 and has a cylindrical stem 147 on the outer surface whereof a threaded set of teeth is defined and interacts with a complementary thread defined at the facing surface of the second body 106.
The cylindrical stem 147 is internally partially hollow so as to define a third seat 125 for a second spring 131 which is accommodated at the other end within an adapted fifth seat 148 defined on the end of the cam 123 which protrudes internally to the first cavity 117a.
The cylindrical stem 147 of the second screw 127 meshes, upon a rotation imparted thereto, with a complementary threaded set of teeth defined on the outer surface of a third cylinder 149 which is arranged coaxially to the first screw 107 and has a first base 150, adjacent to the head 145, which abuts at the end of a third spring 151 which is arranged coaxially and externally to the first spring 124.
Said third spring 151 abuts, at the other end, with a second base 152 of a fourth cylinder 153 which has an axial through hole for the first screw 107 and for the first spring 124.
The ski fastening furthermore comprises a rod 140 which has, at the end of the first body 104 which is adjacent to the cam 123, a pair of shoulders 154 between which a first pin 155 is interposed.
The depressions 156a and 156b, defined at the lower end of a pair of second cams 157a and 157b which are freely pivoted laterally to the body 104 by means of second pins 158a and 158b, are positioned on the ends of said pin 155 which protrude beyond the pair of shoulders 154.
As regards the release of the tip element in limit conditions, the forward sliding of the rod 140 imparts a rotation to the second cams 157a and 157b, which compress the third spring 151 through the sliding imparted to the fourth cylinder 153.
Therefore, for a load equal to the limit value, the release of the boot from the tip element is allowed.
Therefore, this second embodiment, too, achieves the previously mentioned aim and objects.
The materials and dimensions which constitute the individual elements of the safety fastening may naturally be the most appropriate according to the specific requirements. | The ski fastening includes a pivoting toe locking element which provides a first toe holding down locking force by means of a first spring and a rear heel locking element which provides a second heel holding down locking force by means of a second spring. Both the first spring and the second spring are housed in the heel holding device and both the locking forces provided by such springs are simultaneously adjustable upon the activation of a single screw element also provided on the heel holding device. The heel holding device furthermore includes a first body connectable to a ski in an adjustable position and a second body which is slidably supported by the first body in a direction parallel to the longitudinal extension of the ski to thereby maintain a constant distance between the heel holding device and the toe holding device of the fastening even during flexing of the ski during use. | 0 |
FIELD OF THE INVENTION
The invention relates to a concentrate cartridge for a diluting and dispensing container for combining at least two separate components of a multi-component system that are combined before use and subsequently dispensed together as a solution. More particularly, the invention includes a reusable concentrate cartridge for use in a diluting and dispensing container for combining a concentrated material, typically a liquid, with a liquid diluent, such as water. The concentrated material is supplied in a separately packaged cartridge that is easily inserted into and removed from the reusable diluting and dispensing container. After the combined solution of concentrated material and diluent is used, the spent cartridge is removed and replaced by a fresh cartridge. Diluent is resupplied to the diluting and dispensing container and the two components are combined to form a fresh supply of the solution.
BACKGROUND OF THE INVENTION
In many instances it is desirable to retain the components of a multi-component system separate and to combine them shortly before use. This is true of systems wherein the components are incompatible either with each other as well as when it is desired to supply the consumer with a concentrated substance which can be diluted, typically with water, to form a solution.
The present invention provides a dispenser and cartridge of a concentrated substance for use in conjunction with the dispenser to combine the concentrated substance with a diluent material to form a solution having particular performance characteristics. Typical of the concentrated substances useable according to the invention are detergents that can be subsequently diluted with water to form a detergent solution of the proper concentration for use as a window cleaner, spot remover, disinfectant cleanser for hard surfaces, tub and tile cleaners, wall cleaners, etc.
Dispensers for combining the components of a multi-component system shortly before use can be classified into three distinct groups. The first group are those employing reusable containers that can be recharged with a fresh cartridge of concentrate when the solution is expended; a second group wherein the container and cartridge of concentrate are designed for a single use and subsequent disposal; and a third group wherein the cartridge for the concentrate may be refilled with concentrate after being used to produce a diluted operative solution. In the second group, the cartridge of concentrate is typically permanently contained within the container and/or dispenser.
Representative of the first class of container-dispensers is the device disclosed in the U.S. Pat. No. 3,655,096 to Easter. The patent describes a dispensing system employing a replaceable cartridge containing a concentrated liquid material in combination with a bottle and a dispensing pump device. The cartridge has frangible upper and lower surfaces and an annular flange extending from the upper surface. The cartridge is placed in the neck of the bottle and supported by the annular flange resting on the rim of the container neck. The dip tube passes through the cartridge by puncturing both its top and bottom surfaces. The concentrate will drain into and mix with a diluent, such as water. The resulting solution is dispensed by activating the pump mechanism to upwardly draw the solution through the dip tube and to expel it from a dispensing orifice in the pump head.
The second class of multi-component container dispensers includes the devices disclosed in the U.S. Pat. No. 3,024,947 to Jeynes Jr., U.S. Pat. No. 2,653,611 to Smith and U.S. Pat. No. 3,347,410 to Schwartzman. The Jeynes Jr. patent discloses a squirt bottle of the foregoing type wherein the concentrated material is present in a ring shaped aluminum foil cartridge. The concentrate cartridge is placed on a supporting flange located within the neck of the bottle. A closure cap having a dispensing orifice, a dip tube and an annular row of teeth extending downwardly is provided in the Jeynes Jr. system. The upper surface of the concentrate cartridge is punctured by the annular row of teeth when the closure cap is pressed downwardly thereby releasing the concentrate into the diluent contained in the body of the bottle. The resulting solution is expelled through the dip tube and the dispensing orifice by squeezing pressure applied to the bottle, which has flexible plastic walls.
The Schwartzman and Smith patents both provide compartments disposed in the bottle neck for holding a powdered component separate from a liquid diluent in the body of the bottle. A plunger means is provided in the closure cap for combining the powdered component and the diluent in response to downward pressure on the plunger. In Schwartzman the plunger operates through a bellows and displaces the bottom wall of the powder compartment while in Smith the plunger forces the entire compartment into the body of the bottle.
The third class employing a reusable container for the diluting fluid and a reusable cartridge for the concentrate is typically disclosed in U.S. Pat. Nos. 5,957,335 to Otto and 6,041,969 to Parise. The Otto patent discloses a concentrate cartridge comprised of a circular cylinder having one end open and the opposite end closed by a bellows-like wall. The open end is selectively opened and closed by an annular-shaped wall connected to the bellows-like wall by a hollow actuator tube.
The Parise patent discloses a container for a concentrate including a first hollow cylindrical element having an axial hole in its lower part. A second cylindrically symmetrical element is disposed inside the first element and is comprised of a collar in the shape of an inverted cup which is adapted to slide inside the first element in fluid-tight relationship. A third element in the shape of a ring which threads onto the end of the second element and when tightened forms a single piece with the second element. The external diameter of the ring allows it to slide within the hole in the bottom of the first element with engagement in such a way as to obtain a water-tight fit. The aforementioned collar and the ring effectively close the two opposing ends of the first hollow cylindrical element and defines a chamber for the concentrate. Axially movement of the collar of the second element and the associated ring opens the axial hole in the first element allowing the concentrate to exit the first element into an associated bottle containing a diluting fluid.
It is an object of the present invention is to produce a concentrate cartridge for a diluting and dispensing container which may be economically manufactured.
Still another object of the present invention is to produce a concentrate cartridge for a diluting and dispensing container for packaging concentrate to greatly reduce the costs in formulating a desired dilute solution.
Another object of the present invention is to produce a concentrate cartridge for a diluting and dispensing container which may be refilled and reused.
Another object of the present invention is to produce a concentrate cartridge for a diluting and dispensing container which may be easily and economically refilled.
Still a further object of the present invention is to produce a concentrate cartridge for a diluting and dispensing container embodying structural features to capture concentrate overflow from the cartridge.
SUMMARY OF THE INVENTION
The above, as well as other objects and advantages of the invention may typically be achieved by a dispensing container comprising: a bottle, container, or other hollow vessel having a body for containing a liquid diluent and a reduced diameter neck portion having supported therein a cartridge for containing the concentrate substance. The concentrate cartridge comprises a hollow cylindrical element having a first open end forming a closure seat and a second end including a flange extending outwardly of the cylindrical element, an annular collar, and an annular web having a generally U-shaped cross-section interconnecting the collar and the flange of the first cylindrical element; and a hollow tube having a first end portion in fluid-tight sliding relation with the annular collar of the hollow cylindrical element, and a second end terminating into a radially outwardly extending closure adapted to selectively seat with the closure seat of the hollow cylindrical element to form a fluid-tight closure therebetween.
The radially outwardly extending closure is opened in response to a downward force applied to the first end portion of the hollow tube while the hollow cylindrical element of the cartridge is held in place in the dispensing container.
A closure cap including a dispensing means, typically a pump, is provided. The closure cap includes means to mate with the neck portion of the bottle to provide a tight seal between the two members. A dip tube communicating with the dispensing pump is associated with the body portion of the bottle.
The closure cap is joined to the neck portion of the bottle usually by screwing it onto the neck and; the dip tube passes through the central passageway of the cartridge and into the body of the bottle. Before the closure cap is fully seated on the neck of the container, an inner surface of the top of the cap contacts the upper surface of the hollow tube. The additional application of downward axial force to seat the closure cap forces the hollow tube downward until the closure is opened and the concentrate flows into the diluent contained in the body of the bottle to form the desired solution. The solution is dispensed from the bottle through the dip tube and the dispensing orifice as a spray or a steam of liquid in response to activation of a hand pump associated with the closure cap.
BRIEF DESCRIPTION OF THE DRAWINGS
The above objects and advantages of the invention will become readily apparent to those skilled in the art from reading the following detailed description of the invention when considered in the light of the accompanying drawings, in which:
FIG. 1 is an elevational view partially in section of a concentrate cartridge embodying the features of the invention in combination with a diluting and dispensing container, and an associated pump;
FIG. 2 is an enlarged perspective view of the concentrate cartridge illustrated in FIG. 1 partially in section;
FIG. 3 is an exploded view of the container cap, the concentrate cartridge, the upper portion of the diluting and dispensing container including the threaded neck portion, and downwardly depending dip tube of the dispensing pump prior to assembly; and
FIG. 4 is an enlarged cross-sectional view of the upper portion of the diluting and dispensing container illustrated in FIG. 1 with the container cap partially applied prior to the opening of the concentrate container as illustrated in FIG. 1 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, there is illustrated a diluting and dispensing container 10 having a body portion 12 for containing a diluent fluid 14 such as water, for example. The diluting and dispensing container 10 includes a hollow neck portion 16 having external threads 18 formed on the outside surface thereof for engaging the cooperating internal threads 20 formed on the inner surface of an associated closure cap 22 . Other mating means may be used such as, for example, a press fit. The closure cap 22 is adapted to form a seal at the open end of the neck portion 16 of the diluting and dispensing container 10 .
The closure cap 22 is rotatingly coupled to dispensing means provided with a depending dip tube 26 . In the embodiment shown, the dispensing means is a hand pump 24 .
A concentrate cartridge 30 having an outer diameter slightly smaller than the inside diameter of the neck portion 16 , is provided with a main hollow cylindrical body 32 having an outer diameter slightly smaller than the inside diameter of the neck portion 16 . A lower end 34 of the body 32 is open. The opposite end is provided with an outwardly extending annular flange 36 which extends completely around the outer peripheral surface of the body 32 . The juncture of the under surface of the flange 36 and the outer surface of the body 32 may be formed on a radius. The radius terminates in a ledge 38 adapted to rest on the upper open end of the neck portion 16 of the diluting and dispensing container 10 . The adjacent outer surface of the body 32 is flared outwardly slightly as illustrated in FIG. 3 at 38 . The under surface of the flange 36 is generally flat and serves to support the concentrate cartridge 30 within the neck portion 16 of the diluting and dispensing container 10 .
The upper end of the concentrate cartridge 30 includes an annular collar 40 . The annular collar 40 is interconnected to the inner portion of the body 32 and in the region of the flange 36 by an annular web 42 . It will be observed that the inner surface of the upper portion of the body 32 , the annular web 42 , and the outer surface of the annular collar 40 form a trough 44 which is generally U-shaped in cross-section.
The inner surface 46 formed by the juncture of the annular collar 40 and the annular web 42 is inclined inwardly and upwardly from the inner surface of the body 32 to the inner surface of the annular collar 40 .
The concentrate cartridge 30 includes an associated closure member 50 . The closure member 50 is comprised of a hollow tube portion 52 having a radially outwardly extending closure 54 at one end thereof. The closure 54 is formed with a generally flat outer surface 56 and an opposing inner surface 58 . The outer peripheral surface of the inner surface 58 is provided with an inclined camming surface or bevel 60 .
The assembly of the body 32 and the closure member 50 is typically achieved by inserting the free end of the tube portion 52 into the interior of the body 32 toward the open interior of the annular collar 40 . This procedure is simplified by the existence of the inclined inner surface 46 which functions to readily guide the end of the tube portion 52 into the annular collar 40 . To effect a complete closure, the closure member 50 is caused to move axially within the body 32 until the camming surface 60 of the closure 54 cooperates with the lower end 34 of the body 32 to seal in a fluid-tight connection. The free end of the tube portion 52 extends through the annular collar 40 to protrude slightly, as clearly illustrated in FIG. 2 . As a general rule, a concentrate 62 is inserted, manually or automatically, to the interior of the concentrate cartridge 30 before the closure member 50 is closed to seal the concentrate 62 within the concentrate cartridge 30 .
Once filled with the concentrate 62 , the lower end 34 of the concentrate cartridge 30 is inserted into the neck portion 16 of the diluting and dispensing container 10 . The concentrate cartridge 30 is guided to seat properly within the neck portion 16 by the flared portion of the adjacent outer surface of the body 32 . Ideally, the outer surface of the body 32 of the concentrate cartridge 30 is substantially smooth which facilitates sliding and positioning of the concentrate cartridge 30 within the neck portion 16 . A material of construction such as high-density polyethylene, for example, provides such qualities.
When the concentrate cartridge 30 is fully inserted into the neck portion 16 , the ledge 38 abuts the upper edge of the neck portion 16 to suspend the concentrate cartridge 30 within the diluting and dispensing container 10 . The neck portion 16 of the diluting and dispensing container 10 is inserted into the closure cap 22 of the hand pump 24 . The closure cap 22 is then caused to rotate to engage the internal threads 20 and the external threads 18 to effect closure of the diluting and dispensing container 10 . As the closure cap 22 is caused to close on the diluting and dispensing container 10 , the top of the tube portion 52 is contacted by the closure cap 22 and caused to be slid downwardly within the body 32 of the concentrate cartridge 30 . The closure 54 is thereby caused to disengage from the lower end 34 of the body 32 of the concentrate cartridge 30 releasing the concentrate 62 into the diluting and dispensing container 10 .
Undesirable leakage from the concentrate cartridge 30 is minimized due to the tight fit between the annular collar 40 and the tube portion 52 and between the closure 54 and the lower end 34 . Should leakage occur from between the annular collar 40 and the tube portion 52 , during shipment or storage for example, the leaked concentrate 62 is contained within the trough 44 and permitted to dry. The trapping of the leaked concentrate 62 militates against damage to shipping and storage containers, for example.
From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications to the invention to adapt it to various usages and conditions in accordance with the scope of the appended claims. | A reusable concentrate cartridge adapted to be supported by a diluting and dispensing container for combining at least two separate components of a multi-component system, the concentrate cartridge having a hollow cylindrical body and a hollow tube with a closure portion. The concentrate cartridge is caused to open by the rotating engagement of a closure cap on the diluting and dispensing container to which causes the closure portion of the hollow tube to disengage to release the concentrate material. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Applicant hereby claims the benefit of U.S. provisional patent application No. 61/493,034, filed Jun. 3, 2011, the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to crystalline epirubicin hydrochloride and to a method for its production.
Epirubicin and its acid addition salts, such as epirubicin hydrochloride, are compounds from a group of anthracyclines, which have been used since the 1980s as cytostatics for treatment of various types of solid tumors. The structure of epirubicin hydrochloride can be represented by the following formula:
The use of epirubicin for treatment of tumors is the subject of U.S. Pat. No. 5,091,373, for example.
The production of epirubicin is described in U.S. Pat. Nos. 4,112,076 and 5,874,550, among others. For example, epirubicin and its acid addition salts can be synthesized chemically starting from daunorubicin. The production of epirubicin by the fermentation of microorganisms, however, is also possible and disclosed, for example, in European patent application Publication No. EP 1 990 405. Organic and inorganic contaminants typically accumulate during the production of epirubicin, and their proportion can be up to 25 weight percent of the produced product mixture. For this reason, purification of epirubicin or its corresponding acid addition salts after production is essential.
A suitable method for purifying epirubicin hydrochloride emerges from U.S. Pat. No. 4,861,870. Here, epirubicin hydrochloride is precipitated from an aqueous solution with the help of acetone and is obtained as an amorphous solid. With this method it is possible to obtain amorphous epirubicin hydrochloride in largely pure form.
In U.S. Pat. No. 7,485,707 and International patent application Publication No. WO 2010/039159 there are described certain crystalline forms of epirubicin hydrochloride, which are characterized by different x-ray diffraction patterns, that exhibit improved thermal stability compared with known modifications of epirubicin hydrochloride. These crystalline modifications should be able to be obtained by precipitating epirubicin hydrochloride from a solution or a gel by adding hydrophilic organic solvent. With the post-processing of the method described in these patent documents, however, it was determined that crystalline epirubicin hydrochloride cannot be obtained with the described x-ray diffraction patterns under the specified conditions.
Furthermore, the problem is known from the prior art that the production or crystallization of epirubicin hydrochloride leads to an undesired formation of dimers and decomposition products, such as doxorubicinone.
Therefore, there is also a need for a thermally stable modification of crystalline epirubicin hydrochloride and a simple and reliable method for producing such a thermally stable modification of crystalline epirubicin hydrochloride in high purity.
BRIEF SUMMARY OF THE INVENTION
The invention is therefore based on the object of providing a thermally stable modification of crystalline epirubicin hydrochloride.
The invention is further based on the object of providing a simple and reliable method for producing such a thermally stable modification of crystalline epirubicin hydrochloride in high purity.
The invention therefore provides a method for producing crystalline epirubicin hydrochloride, comprising the steps:
(a) providing of epirubicin hydrochloride; (b) producing a mixture containing the provided epirubicin hydrochloride and at least one alcohol selected from the group consisting of 1-butanol, 2-butanol, and 1-pentanol; and (c) crystallizing epirubicin hydrochloride from this mixture.
The invention also provides crystalline epirubicin hydrochloride obtained by this method.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The foregoing summary, as well as the following detailed description of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.
FIG. 1 is a typical DSC diagram of crystalline epirubicin hydrochloride produced according to an embodiment of the invention; and
FIG. 2 is a typical powder x-ray diffraction diagram of crystalline epirubicin hydrochloride produced according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
According to the invention, crystalline epirubicin hydrochloride is produced.
This crystalline epirubicin hydrochloride preferably has a peak in a Differential Scanning calorimetry (DSC) diagram having a maximum intensity in the temperature range of 195-205° C., more preferably having a maximum intensity in a temperature range of 198-202° C., and in particular having a maximum intensity at a temperature of 200° C. This peak preferably involves an exothermic peak.
According to another preferred embodiment, crystalline epirubicin hydrochloride of the invention has an additional peak in the Differential Scanning calorimetry (DSC) diagram having a maximum intensity in the temperature range of 240-260° C. and in particular having a maximum intensity in the temperature range of 245-255° C. This additional peak preferably involves an endothermic peak.
The Differential Scanning calorimetry (DSC) diagram can be obtained within the scope of the invention, for example, by heating a sample of crystalline epirubicin hydrochloride (for example corresponding to a quantity of 1-8 mg epirubicin hydrochloride) to 30-350° C. at a heating rate of 10-20° K/min, preferably 10° K/min, in a DSC calorimeter.
A typical DSC diagram of crystalline epirubicin hydrochloride according to an embodiment of the invention is shown in FIG. 1 .
Crystalline epirubicin hydrochloride of the invention is preferably characterized at least by peaks in a powder x-ray diffraction diagram at average values for the diffraction angle (2Θ) in the following ranges: 5.04-5.14, 9.00-9.20, 13.50-13.80, 22.00-22.20, 22.40-22.50, 22.51-22.60, 23.90-24.10, and 25.70-25.90.
According to one preferred embodiment, the crystalline epirubicin hydrochloride has at least peaks at the following average values for the diffraction angle (2Θ) in a powder x-ray diffraction diagram: 5.09, 9.10, 13.63, 22.10, 22.46, 22.52, 24.00, and 25.77.
According to one especially preferred embodiment, crystalline epirubicin hydrochloride is characterized by a powder x-ray diffraction pattern having relative intensities P (%) at average values for the diffraction angle (2Θ) according to the following table:
Diffraction angle
Preferred
(2Θ)
Relative intensity P(%)
relative intensity P(%)
5.09
100-80
100
9.10
80-60
71
13.63
100-80
98
22.10
55-45
50
22.46
95-75
85
22.52
100-80
100
24.00
100-80
100
25.77
65-50
56
According to another preferred embodiment, crystalline epirubicin hydrochloride is characterized preferably at least by peaks at the following average values for the diffraction angle (2Θ) in a powder x-ray diffraction diagram: 5.09, 9.10, 9.47, 11.51, 12.01, 12.34, 13.62, 14.59, 16.11, 16.37, 16.50, 18.02, 19.11, 19.36, 20.82, 21.02, 21.37, 22.10, 22.46, 22.52, 23.29, 24.00, 25.77, 27.67, and 29.69.
According to another especially preferred embodiment, crystalline epirubicin hydrochloride is characterized by a powder x-ray diffraction pattern having relative intensities P (%) at average values for the diffraction angle (2Θ) according to the following table, wherein only relative intensities P≧10% are specified:
Preferred relative
Diffraction angle (2Θ)
Relative intensity P(%)
intensity P(%)
5.09
100-80
100
9.10
80-60
71
9.47
15-10
13
11.51
25-18
22
12.02
22-14
18
12.34
30-20
26
13.63
100-80
98
14.59
60-40
49
16.11
40-30
34
16.50
45-33
37
18.02
30-20
24
19.11
25-15
21
19.36
35-25
29
20.82
25-15
20
21.02
33-20
27
21.37
40-50
46
22.10
55-45
50
22.46
95-75
85
22.52
100-80
100
24.00
100-80
100
25.77
65-50
56
27.67
55-40
47
29.69
25-40
32
According to the invention, it can be preferred that the term “peak” is understood to be the signal of this peak having the maximum intensity.
A typical powder x-ray diffraction diagram of crystalline epirubicin hydrochloride produced according to an embodiment of the invention is shown in FIG. 2 .
The above values relate to x-ray diffraction measurements measured with a powder x-ray diffractometer made by the company Stoe (Darmstadt) by an IPPSD detector (image plate position-sensitive detector) using Cu—Kα radiation (λ=1.5406 Å) (Ge monochromator). The measurement range for 2Θ was 3 to 79. The measurement devices were calibrated against Si 5N=99.999%. The accuracy of the obtained values equals 1.0%.
For producing crystalline epirubicin hydrochloride, initially epirubicin hydrochloride is provided in a step (a). This epirubicin hydrochloride can be produced in a known manner, for example using fermentation or chemical synthesis.
The provision of epirubicin hydrochloride can take place as a solid, in a suspension, or in a solution. Preferably, epirubicin hydrochloride is provided in solid form or in a solution.
If epirubicin hydrochloride is provided as a solid, this can be present as amorphous epirubicin hydrochloride or as crystalline epirubicin hydrochloride.
If epirubicin hydrochloride is provided in a solution, then it preferably involves an aqueous solution of epirubicin hydrochloride. According to one especially preferred embodiment, this aqueous solution is a concentrated aqueous solution of epirubicin hydrochloride. By aqueous solution of epirubicin hydrochloride is understood, according to the invention, a solution containing epirubicin hydrochloride and water. The percentage of water in this solution is preferably in the range of 30-70 volume percent and more preferably in the range of 40-60 volume percent, relative to the total volume of aqueous solution containing epirubicin hydrochloride.
In addition to epirubicin hydrochloride and water, the aqueous solution can however optionally also contain additional components, in particular at least one additional solvent. This at least one additional solvent can involve, for example, an alcohol. Here, as alcohols, ethanol, 1-propanol, 2-propanol, or mixtures thereof are preferred. The proportion of the at least one alcohol preferably lies in the range of 30-70 volume percent and more preferably in the range of 40-60 volume percent, relative to the total volume of the aqueous solution containing epirubicin hydrochloride. The content of epirubicin hydrochloride in this aqueous solution equals preferably 100-400 g/l and more preferably 150-350 g/l, relative to the total volume of the aqueous solution containing epirubicin hydrochloride. According to one preferred embodiment, the pH value of the aqueous solution containing epirubicin hydrochloride lies in the range of 3.5-4.5.
The epirubicin hydrochloride provided in step (a) is used in a step (b) for producing a mixture. For this purpose, the provided epirubicin hydrochloride, preferably present as a solid or in a solution, is combined with at least one alcohol selected from the group consisting of 1-butanol, 2-butanol, and 1-pentanol.
Accordingly, a mixture is formed that contains at least epirubicin hydrochloride and at least one alcohol selected from the group consisting of 1-butanol, 2-butanol, and 1-pentanol. It has proven especially advantageous for the crystallization to produce a mixture that contains, in addition to epirubicin hydrochloride, at least 1-butanol.
The presence of an alcohol selected from the group consisting of 1-butanol, 2-butanol, and 1-pentanol, in particular 1-butanol, contributes surprisingly to the prevention of gel formation that is otherwise typical for epirubicin hydrochloride and that is an obstacle to crystallization of epirubicin hydrochloride. Accordingly, just the presence of at least one alcohol selected from the group consisting of 1-butanol, 2-butanol, and 1-pentanol allows the growth of epirubicin hydrochloride crystals.
According to one preferred embodiment, the proportion of the at least one alcohol selected from the group consisting of 1-butanol, 2-butanol, and 1-pentanol lies in the range of 5-100 volume percent, more preferably in the range of 5-50 volume percent, even more preferably in the range of 5-30 volume percent, especially preferred in the range of 6-20 volume percent, and very especially preferred in the range of 7-15 volume percent, relative to the total volume of the mixture in step (b). At a concentration of less than 5 volume percent of the at least one alcohol selected from the group consisting of 1-butanol, 2-butanol, and 1-pentanol, relative to the total volume of the mixture, it has been shown that the tendency toward crystallization of epirubicin hydrochloride decreases significantly.
According to another preferred embodiment, the mixture in step (b) contains, in addition to epirubicin hydrochloride and at least one alcohol selected from the group consisting of 1-butanol, 2-butanol, and 1-pentanol, at least one additional alcohol. This additional alcohol is preferably selected from the group consisting of ethanol, 1-propanol, and 2-propanol. According to one especially preferred embodiment, the additional alcohol is 2-propanol.
Preferably, the proportion of the at least one additional alcohol selected from the group consisting of ethanol, 1-propanol, and 2-propanol lies in the range of 5-95 volume percent, more preferably in the range of 10-94 volume percent, even more preferably in the range of 50-93 volume percent, especially preferred in the range of 75-92 volume percent, and very especially preferred in the range of 80-90 volume percent, relative to the total volume of the mixture.
If an additional alcohol is contained in the mixture, wherein this additional alcohol is selected from the group consisting of ethanol, 1-propanol, and 2-propanol, then it can be preferred that the ratio of the volume of this additional alcohol to the volume of the alcohol selected from the group consisting of 1-butanol, 2-butanol, and 1-pentanol lies in the range of 3:1 to 20:1, more preferably in the range of 5:1 to 15:1, and even more preferably in the range of 7:1 to 10:1.
The mixture produced in step (b) can also have other additional components. One preferred additional component can be, for example, water. Preferably, the proportion of water is below 7 volume percent, relative to the total volume of the mixture. A higher percentage of water in the mixture could reduce the yield. According to one preferred embodiment, the proportion of water is in the range of 0.5-7 volume percent and more preferably in the range of 3-5 volume percent, relative to the total volume of the mixture.
It has proven especially advantageous if, in step (b), a mixture is produced that contains, in addition to epirubicin hydrochloride, 80-90 volume percent 2-propanol, 5-15 volume percent 1-butanol, and 2-6 volume percent water, relative to the total volume of the mixture.
According to an embodiment of the invention, it can be further advantageous that the proportion of epirubicin hydrochloride lies in the range of 5-100 g/l, preferably in the range of 6-100 g/l, more preferably in the range of 10-50 g/l, and even more preferably in the range of 25-35 g/l, relative to the total volume of the mixture in step (b). A concentration of epirubicin hydrochloride in this range leads to a surprisingly high yield of crystalline epirubicin hydrochloride, which in this case can be, for example, approximately 95 weight percent.
The mixture produced in step (b) can be a solution or a suspension. A solution of epirubicin hydrochloride is typically obtained when a solution of epirubicin hydrochloride, for example an aqueous solution of epirubicin hydrochloride, is present before the addition of the at least one alcohol. In contrast, the mixture in step (b) is typically present as a suspension when epirubicin hydrochloride is present as a solid before the addition of the at least one alcohol.
A pH value of the mixture in step (b) in the range of 2.5-4.5 has proven especially advantageous for the crystallization. An optimum crystallization is obtained here if the pH value of the mixture in step (b) lies in the range of 3.0-4.5, more preferably in the range of 3.5-4.5, and in particular in the range of 3.9-4.1. If the mixture is produced by adding the at least one alcohol to epirubicin hydrochloride as a solid, then the mixture typically already has a pH value in this range. If the production of the mixture is realized by adding the at least one alcohol to a solution containing epirubicin hydrochloride, then the mixture could have a higher pH value. In this case, the pH value can be adjusted to the preferred range, for example by adding hydrochloric acid.
In step (c) the crystallization of epirubicin hydrochloride takes place. For this purpose, the mixture obtained in step (b) can be left standing, for example, until crystalline epirubicin hydrochloride forms. If necessary, the mixture can be stirred here.
The mixture can also be heated, however, for accelerating the crystallization. According to one preferred embodiment, the mixture is heated to a temperature in the range of 40-80° C., more preferably in the range of 50-75° C., and even more preferably in the range of 60-70° C. At temperatures below 40° C. the crystallization of epirubicin hydrochloride from the mixture takes place only slowly, while at temperatures above 80° C. the epirubicin hydrochloride obtained in the mixture is slowly broken down. The mixture is preferably heated while being stirred.
According to another preferred embodiment, the mixture is left at a temperature in the range specified above for a time period of at least two hours, for example for a time period in the range of 2-8 hours, 4-8 hours, or 4-6 hours. Here, the mixture can optionally also be stirred.
Then, the heated mixture can be cooled. The cooling can take place, for example, at a temperature in the range of 20-30° C., in particular at a temperature of 25° C.
It has been shown that crystalline epirubicin hydrochloride is thermodynamically more stable than amorphous epirubicin hydrochloride. With crystallization of epirubicin hydrochloride from a solution, crystalline epirubicin hydrochloride is typically obtained directly. If the crystallization of epirubicin hydrochloride is performed from a suspension containing amorphous epirubicin hydrochloride, then the amorphous epirubicin hydrochloride typically initially present in the suspension as a solid is gradually converted into the thermodynamically more stable crystalline epirubicin hydrochloride.
After the crystallization, the produced crystals can be separated from the rest of the mixture. The separation here takes place preferably by filtration or distillation.
If necessary or desired, the crystals can then be washed. The washing can take place, for example, with a ketone, for example acetone.
After the optional washing of the crystals, the crystals can in turn be separated from the washing solution. Here also, the separation typically takes place by filtration or distillation.
The isolated solid can finally be dried. The drying preferably takes place until the weight becomes constant and also preferably under a vacuum.
The invention is described below with reference to examples that should not, however, limit the scope of protection.
EXAMPLES
Example 1
9.0 g amorphous epirubicin hydrochloride was suspended in a mixture of 12 ml water, 258 ml 2-propanol, and 30 ml 1-butanol. This suspension was heated to 65° C. while stirring and left at this temperature for four hours. Here, the solid contained in the suspension was not completely dissolved, but instead was gradually converted from an amorphous modification into a crystalline modification. The suspension was cooled stepwise to a temperature of 22° C. After the removal of the solvent contained in the suspension by filtration, the crystals were washed with acetone and dried for 24 hours under vacuum after the removal of acetone.
Then, the purity of the resulting epirubicin hydrochloride was tested. The presence of dimers or decomposition products was not detected. The yield equaled 95%.
The produced crystalline epirubicin hydrochloride was subjected to a test of thermal stability. For this purpose, the produced crystals were stored at a temperature of 40° C. for a time period of one week, two weeks, and three weeks. Within this time frame, no decomposition of the crystalline epirubicin hydrochlorides could be detected. Instead, the crystals remained in unchanged form.
Example 2
10.0 g amorphous epirubicin hydrochloride was dissolved in a mixture of 13 ml water and 13 ml 2-propanol, in order to prepare a solution containing epirubicin hydrochloride. This solution was then mixed with 33 ml 1-butanol and 274 ml 2-propanol. The produced mixture was heated to 65° C. and left at this temperature for four hours, whereby epirubicin hydrochloride crystals were formed. Then, the obtained suspension was cooled stepwise to a temperature of 22° C. The solvent contained in the suspension was removed by filtration, and the crystals remaining as filter residue were washed with acetone. After removing the acetone, the crystals were dried for 24 hours under vacuum.
Then, the purity of the produced epirubicin hydrochlorides was tested. The presence of dimers or decomposition products was not detected. The yield equaled 95%.
The produced crystalline epirubicin hydrochloride was subjected to a test of thermal stability. For this purpose, the produced crystals were stored at a temperature of 40° C. for a time period of one week, two weeks, and three weeks. Within this time frame, no decomposition of the crystalline epirubicin hydrochlorides could be detected. Instead, the crystals remained in unchanged form.
Comparison Example 1
A solution of epirubicin hydrochloride (10.0 g) was produced in water (pH 3.5), and the solution was subjected to drying under vacuum at a temperature of 40° C. until a gel-like state was reached. The solution thus obtained was mixed with 300 ml acetone, in order to precipitate epirubicin hydrochloride from this solution. The precipitate produced was obtained from the solution by filtration and washed with 50 ml acetone.
Then, the purity of the obtained epirubicin hydrochloride was tested. The yield initially equaled 95%. The presence of dimers was detected.
The epirubicin hydrochloride produced was subjected to a test of thermal stability. For this purpose, the epirubicin hydrochloride was stored at a temperature of 40° C. for a time period of one week, two weeks, and three weeks. Within this time frame, a thermal decomposition of epirubicin hydrochloride amplified with increasing storage period by two percent respectively was observed.
Comparison Example 2
Example 1 of U.S. Pat. No. 7,485,707 was followed, and initially a solution of epirubicin hydrochloride (10.0 g) was produced in water (pH 3.5), which was subjected to drying under vacuum at a temperature of 40° C. until a gel-like state was reached. The solution produced was mixed with twelve times the volume of 1-propanol and stirred for three hours at a temperature of 60° C. No crystalline epirubicin hydrochloride according to the present invention was produced.
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 crystalline epirubicin hydrochloride and a method for its production are provided. The method for producing the crystalline epirubicin hydrochloride includes the steps: (a) providing epirubicin hydrochloride, (b) producing a mixture containing the provided epirubicin hydrochloride and at least one alcohol selected from the group 1-butanol, 2-butanol, and 1-pentanol, and (c) crystallizing epirubicin hydrochloride from this mixture. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/069,090 filed Mar. 12, 2008.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention is directed to low chlorine epoxy resin formulations having improved corrosion resistance.
[0004] 2. Brief Description of the Related Art
[0005] Epoxy resins have a broad range of applications within electronics and electrical engineering. They are used for molding compounds, glob top materials, printed circuit board materials, resist materials, adhesives, underfillers, and films and for shielding semiconductor, electronic and optoelectronic components. Glycidyl and polyglycidyl ether resins frequently serve as the base materials for these applications. As a general rule, these are produced by reacting respective phenols, bisphenols, polyphenols or novolak resins with epichlorohydrin.
[0006] The majority of technically available resins are obtained by the conversion of the polyphenols with epichlorohydrin. It is well known that the glycidyl ether compounds prepared by means of epichlorohydrin, especially those prepared industrially, are always contaminated with chlorine, which is present in the epoxy resins as ionic chloride, as hydrolysable chlorine (1,2-chlorohydrin) and non-hydrolyzable chlorine (alkyl chlorides). These resins typically have residual chlorine contents in excess of 1000 ppm. The residual chlorine can, particularly at the high temperature conditions which exist in current high-performance electronic systems, corrode metal parts of the underlying electronic components and will eventually cause failure of the part. While chlorine-free epoxy resins are preferable for various reasons, they appear to be manufacturable, if at all, only with a large capital outlay and thus at high cost.
[0007] Higher requirements with respect to the purity are continually being imposed on epoxy resins, especially those which are used for the production of electrical and electronic components, in order to reduce the corrosion influence of the residual chlorine content on device components, in particular contact metals such as copper and aluminum. Epoxy resins of this sort are required in particular for cationic hardening. In addition, given other hardening mechanisms, they can also replace chlorine-containing polyepoxies, which are currently an essential component of molding compounds and circuit board materials.
[0008] The ionically bound chloride produced during epoxy resin synthesis can be removed to low ppm levels by means of aqueous washing processes. The content of ionic chloride can be reduced to less than 0.0001% (1 ppm) by weight using the sometimes extravagant aqueous washing techniques. In contrast, organic compounds containing chlorine which develop as byproducts and which cause the epoxy materials to have a total chlorine content of up to 0.5% (5000 ppm) by weight are not removed by means of aqueous washing processing. Aqueous alkali treatments have been shown to reduce the hydrolysable chlorine content to as low as 0.0028% (28 ppm) by weight, but more typically 100 to 300 ppm. See, for example, U.S. Pat. No. 4,668,807 to Darbellay et al. The total organic chlorine content, which includes even less hydrolyzable chlorine, is higher yet.
[0009] Processes to reduce the total chlorine content using crystallization of diglycidyl ethers from organic solvent solutions such as isopropyl alcohol have been known for some time, and have reduced the total chlorine contents to 300 to 500 ppm. See, for example, U.S. Pat. No. 5,098,965 to Bauer et al. However, these levels have still been inadequate to protect against the corrosion of sensitive parts. Epoxy resin such as bisphenol A diglycidyl ether or bisphenol F diglycidyl ether with a total chlorine content of less than 100 ppm have until recently unknown. Epoxy novolak resins with such low total chlorine contents are still unknown. Glycidyl ether resins containing less than 100 ppm total chlorine content have now been reported by Gröppel (WO 03/072627 A1, EP 1 478 674 B1 and US Patent Application Publication 2005/0222381 A1) and have been reported to produce electronic components with reduced susceptibility to corrosion. Test boards coated with several low total chlorine resins were subjected to 100 volts DC in an 85° C., 85% relative humidity climate for 1000 hours and were reported to show no visible signs of corrosion and no significant changes in the insulation resistance could be determined. Total chlorine levels less than 100 ppm were reported to be required to produce such low levels of corrosion.
[0010] The present inventors attempted to use such low total chlorine epoxy resins to produce both liquid and dry film photoimagable resist compositions for use in MEMS and wafer level packaging applications and have found that even these formulations needed additional improvements to achieve the highest possible corrosion resistance on fine copper and aluminum structures with geometries as small as 2 to 5 μm. In choosing these additional improvements one must also be cognizant that they also need to be acceptable for semiconductor and CMOS fabrication processes. The present invention is believed to be an solution to these problems.
SUMMARY OF THE INVENTION
[0011] In one aspect, the present invention is directed to a low chlorine photoresist formulation, comprising:
[0012] from about 2-90 wt % of an epoxy resin;
[0013] from about 0.25-10 wt % of a photoacid generator;
[0014] from about 2-100 ppm of a barium, calcium, or zinc organometallic compound; and
[0015] from about 10-98 wt % of a solvent;
[0016] wherein said formulation has a total free chlorine content of 300 ppm or less; and wherein the weight percents of said epoxy resin, photoacid generator and organometallic compound are based on the total solids weight, and wherein the weight percent of said solvent is based on the total weight of said formulation
[0017] In another aspect, the present invention is directed to products, including dry film products, made from the low chlorine photoresist formulation above.
[0018] In another aspect, the present invention is directed to a product, such as a MEMS device, a microsystem, or packaging, made from the above composition or its dry film.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Recently a few bisphenol A and bisphenol F diglycidyl ether resins with total chlorine contents below 100 ppm have become available. These resins are low MW solid or semi-solid resins with poor resist forming properties, tend to be quite brittle before cure and lead, in particular, to poor dry film resist properties. The present inventors have now formulated these resins into cationically cured epoxy resist formulations using photoacid generators such as used in SU-8 resists available commercially from MicroChem Corp. (Newton, Mass.), preferentially incorporating chlorine-free modifiers to improve film forming properties, where necessary.
[0020] The present inventors have combined these resins with various chlorine-free flexibilizing agents, added photo acid generators commonly used in cationic curing of epoxy resins, and a coating solvent to produce resist products with improved film forming properties. These formulations are similar to SU-8 2000 Resist (MicroChem) and the SU-8 Flex resist formulations disclosed in U.S. Pat. No. 6,716,568 and U.S. application Ser. No. 10/945,344, where the epoxy novolak resin has been replaced by an epoxy copolymer resin of bisphenol A diglycidy ether and bisphenol A. These resist formulations were spin coated onto suitable substrates then dried or cast onto PET films, dried and made into dry film resists, which were subsequently laminated onto the suitable substrates. These films were coated onto 100-200 nm of aluminum coated onto glass substrates, exposed through a mask, post exposure baked, and developed with a suitable solvent to give a film with an array of cavities in the film, then cured at 150° C. for 30 min in air. Such structures were next subjected to a Pressure Cooker Test (PCT) at 120° C., 60-100% humidity for 96 to 112 hours. All samples on glass showed some corrosion under the testing conditions, but the films prepared using low chlorine resists were significantly superior to films prepared with low chloride, but not low chlorine resists or a thermally cured low chloride epoxy system. Films coated onto Al, Al/Cu 1% or Cu on silicon substrates performed significantly better and etching only occurred in the less effective formulations. The samples containing a flexibilizer showed excellent film characteristics and the best corrosion resistance.
[0021] Aluminum acetylacetonate is a widely used and reported gettering agent, and has been successfully used in a number of underfiller and printed circuit board materials. However, it is a highly toxic material and is also a highly mobile ion in semiconductor applications, both negative attributes for wafer level IC or CMOS applications. Calcium, barium and zinc organometallic compounds such as the acetylacetonates are less toxic and far larger molecular species. All three metallic species show very low ion mobility and barium in particular has such a low ion mobility that it is not regulated in IC or CMOS applications. With a low chloride resist formulation we evaluated the addition of 0.1% on solids of aluminum acetylacetonate (control), zinc acetylacetonate, calcium acetylacetonate and barium acetylacetonate as gettering agents. Only the aluminum acetylacetonate fully dissolved in the resist formulation, zinc acetylacetonate was almost completely dissolved, and the others left excess insoluble organometallic solid. However, aluminum and zinc acetylacetonate both inhibited the photoimaging of the compositions at the concentrations used, 1000 ppm. Lower concentrations, <100 ppm may have imaged but were not evaluated. The remaining resists were evaluated as above and the samples containing the gettering agent calcium and barium acetylacetonate gave improved corrosion resistance and were found to be superior. This work showed that the addition of gettering agents to a low chloride resist formulation, containing as low as 1 ppm of ionic chloride had slightly improved the corrosion resistance of a resist formulation, but not nearly to the degree that was seen with the low chlorine resist formulations. Thus neither the use of a low chlorine resist nor the use of gettering agents by themselves was sufficient to provide corrosion resistance to the fine aluminum films.
[0022] When 0.1% of barium acetylacetonate was added to a low chlorine resist formulation and the insoluble solid excess removed by filtration, the total barium content in the resist formulation was found to be less than 50 ppm. Surprisingly, we found that even a low total chlorine dry film resist formulation containing less than 10 ppm barium as barium acetylacetonate when laminated onto an aluminum metallized SAW filter device now successfully passed both a 96 hr, 131° C., 85% relative humidity pressure cooker test and a 85° C., 85% humidity HAST test for more than 200 hours with no detectable corrosion under microscopic investigation. A similar resist sample not containing the barium compound was found to give inferior results.
[0023] The present inventors have therefore found that epoxy resins with total chlorine contents of less than 100 ppm formulated into compositions comprising a photo acid generator commonly used in cationic curing of epoxy resins, a suitability small amount of an organometallic compound and a coating solvent produce resist products of the present invention. Various additives can be added to improve the film forming capability or physical properties of the composition, such as other low chlorine or chlorine-free resins, chlorine-free flexibilizing agents, adhesion promoters, surfactants, inhibitors, dyes, fillers, etc. The compositions can be coated by various means such as spin coating or spray coating onto various substrates such as silicon wafers and baked at 50 to 150° C. to remove the coating solvent resulting in a nearly solventless resist film covering the substrate. The compositions can also be coated and dried on a carrier film to prepare a dry film version of the composition containing little of no residual solvent. The resulting liquid or dry film products can be used as photoresist products in micro electo mechanical systems (MEMS), also called microsystems or in packaging or wafer level packaging applications.
[0024] Suitable epoxy resins comprise 2-99 percent of the final film composition, preferably 85-99 percent based on the total solids weight in the composition, and contain less than 300 ppm of total chlorine as determined by the carbitol method, preferentially less than 100 ppm. As defined herein, the phrases “low chlorine” and “low chlorine content” refers to compositions containing 300 ppm or less of total chlorine, and more preferably 100 ppm or less of total chlorine. The type of epoxy resin is insignificant as long as it provides the desired film properties and lithographic performance. The resin can also be a blend of two or more different resins selected for their particular properties, as long as all resin components exhibit very low total chlorine contents. Acceptable resins or resin blends must be capable by themselves of forming films which are not too sticky nor too brittle and can be acceptably formulated into the present formulations or can be modified with suitable low chlorine (as defined above) or chlorine-free flexibilizers or plasticizers to give the desired film forming properties. The photoacid generator is typically a triarylsulfonium or diaryliodonim salt of a strong acid such as hexafluoroantimonate, or other perfluoronated acids or fluoromethides. Most typically a triaryl or mixed triarylsulfonium salt is employed. The amount of photoacid generator can range from approximately 0.25% of the composition to approximately 10% of the composition based on the total solids weight, but more commonly ranges between 0.25 and 5 percent. The organometallic component is typically a barium, calcium or zinc compound with at least some limited solubility in the composition and the metallic species concentration in the final film ranges from 2 to 100 ppm or more, but preferably 5 to 50 ppm. Most commonly used are the acetylacetonate complexes of these metals, but other complexing agents would work acceptably as well. Barium is the preferred metallic species.
[0025] Any suitable chlorine-free solvent or blend of solvents which can dissolve all of the components and give good film forming properties to the resist solution can be used. A wide range of solvents are acceptable, but the most commonly used are ketones, ethers and esters such a acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, cyclopentanone, cyclohexanone, 1,3-dioxolane, 2-ethoxyethyl acetate, 2-methoxylpropyl acetate, dimethoxypropane, ethyl lactate, and 2-ethoxyethylpropionate, or other unique solvents such as gamma-butyrolactone or propylene carbonate. The solvent comprises 10-98 percent by weight of the composition, typically 20-95 percent, and little to none of the dried film compositions.
[0026] A wide range of flexibilizers can be employed and can comprise 5-25 percent of the composition, preferably 5-15 percent. Suitable flexibilizers are low molecular weight glycidyl, diglycidyl or polyglycidyl ethers containing less than 300 ppm of total chlorine as determined by the carbitol method or various polyols such as caprolactone polyols. Other flexiblizers are also usable. The exact composition of the flexibilizer is unimportant as long as it is chlorine-free or contains very low total chlorine and provides the desirable film forming and lithographic properties to the film.
EXAMPLES
[0027] The following examples are meant to illustrate, but in no way limit the present invention.
Example 1
[0028] To a 50 gm sample of SU-8 3000 Resist [generically a mixture of an epoxidized bisphenol A novolak resin (SU-8 resin, Hexion, Houston Tex.) and other epoxy resins, a mixed triarylsulfonium hexafluoroantimonate salt (Cyracure UVI-6976, Dow Chemical) and gamma-butyrolactone as solvent], available commercially from MicroChem Corp. (Newton, Mass.), in an amber glass bottle was added 0.035 gm (0.1%) of aluminum acetylacetonate. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 2-8 hrs. The mixture was allowed to stand until cool then microfiltered at 0.2 μm.
Example 2
[0029] To a 50 gm sample of SU-8 3000 epoxy resist in an amber glass bottle was added 0.035 gm (0.1%) of aluminum phenoxide. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 2-8 hrs. The mixture was allowed to stand and the undissolved solids filtered off by microfiltration at 0.2 μm.
Example 3
[0030] To a 50 gm sample of SU-8 3000 epoxy resist in an amber glass bottle was added 0.035 gm (0.1%) of barium acetylacetonate. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 2-8 hrs. The mixture was allowed to stand and the undissolved solids filtered off by microfiltration at 0.2 μm.
Example 4
[0031] To a 50 gm sample of SU-8 3000 epoxy resist in an amber glass bottle was added 0.035 gm (0.1%) of calcium acetylacetonate. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 2-8 hrs. The mixture was allowed to stand and the undissolved solids filtered off by microfiltration at 0.2 μm.
Example 5
[0032] SU-8 3000 resist as well as the formulations produced in Examples 1 to 4 were spin coated onto 200 nm of aluminum deposited onto borosilicate glass to give approximately 50 μm coatings, then baked, UV imaged through a mask, post exposure baked for 5 min, and developed with 2-methoxypropyl acetate for 3 to 5 min to create a resist pattern on the Al coated substrates with 1 to 2 mm holes in the otherwise crosslinked SU-8 3000 resist. The imaged substrate was further cured at 150° C. for 30 minutes to provide a cured article common to the art. The glass substrates were then placed in a pressure cooker with 50 to 100 ml of DI water, sealed, then heated to 130° C. The samples were examined daily, by venting the vacuum and removing the hot parts from the pressure cooker, visually examining, quickly returning the parts and reheating for an additional time period for a total of 7 days. In the early stages of corrosion, pinholes in the aluminum were noticed and as the corrosion advanced the aluminum was totally etched away. All samples showed significant corrosion; Example 1 showed some improvement over the SU-8 3000 film and Examples 3 and 4 were slightly better again, but with obvious corrosion.
Example 6
[0033] To a 50 gm of a mixture of an epoxidized bisphenol A novolak resin (SU-8 resin, Hexion, Houston Tex.) and other epoxy resins with a total chlorine content of approximately 800 ppm was added 0.25 gm of a proprietary tris(trifluoromethanesulfonyl)methide photoacid generator (GSID 26-1, from Ciba Inc), and 20 to 60 gm of cyclopentanone as solvent. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 6-8 hrs to dissolve all of the ingredients. The mixture was allowed to stand until cool then microfiltered.
Example 7
[0034] In an amber glass bottle was added 42.8 gm of a proprietary copolymer of bisphenol A diglycidyl ether and bisphenol A epoxy resin containing less than 100 ppm of total chlorine content as measured by the carbitol method, 4.9 gm of Tone 305, 1.0 gm of γ-glycidoxypropyl trimethoxysilane (Z-6040 from Dow Chemical), 3.5 gm of a mixed triarylsulfonium hexafluoroantimonate (Cyracure UVI-6976), 0.01 gm of a surfactant (Baysilone 3739 from Bayer) 22.7 gm of 1,3-dioxolane and 1.8 gm of 2-pentanone. Th mixture was immediately rolled on a roller mill under a infrared heat lamp at 40-60° C. for 12-18 hrs until completely dissolved. This formulation gave a film with good coating qualities.
Example 8
[0035] This Example was prepared in the same way as Example 7 except the Tone 305 is replaced by a proprietary polyfunctional polyol (CDR-3314 from King Industries, Norwalk, Conn.). This formulation gave a film with good coating qualities.
Example 9
[0036] This Example was prepared in the same way as Example 8 except the Baysilone 3739 is replaced by a proprietary fluorinated surfactant (FluorN 562, from Cytonix Corp., Beltsville, Md.). This formulation gave a film with good coating qualities.
Example 10
[0037] This Example was prepared in the same way as Example 9 except the Cyracure UVI-6976 is replaced by a proprietary tris(trifluoromethanesulfonyl)methide photoacid generator (GSID 26-1, from Ciba Inc). This formulation gave a film with good coating qualities.
Example 11
[0038] This Example was prepared in the same way as Example 10 except the solvent mixture is replaced by propylene carbonate.
Example 12
[0039] This Example was prepared in the same way as Example 11 except no surfactant was used.
Example 13
[0040] To a 50 gm sample of the formulation prepared in Example 6 was added 0.035 gm (0.1%) of barium acetylacetonate. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 6-8 hrs. The mixture was allowed to stand until cool and the undissolved solids filtered off by microfiltration.
Example 14
[0041] To a 50 gm sample of the formulation prepared in Example 7 was added 0.035 gm (0.1%) of barium acetylacetonate. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 2-8 hrs. The mixture was allowed to stand until cool and microfiltered at 0.2 μm.
Example 15
[0042] To a 50 gm sample of the formulation prepared in Example 8 was added 0.035 gm (0.1%) of barium acetylacetonate. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 2-8 hrs. The mixture was allowed to stand until cool and the undissolved solids filtered off by microfiltration at 0.2 μm.
Example 16
[0043] To a 50 gm sample of the formulation prepared in Example 9 was added 0.035 gm (0.1%) of barium acetylacetonate. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 2-8 hrs. The mixture was allowed to stand until cool and the undissolved solids filtered off by microfiltration at 0.2 μm.
Example 17
[0044] To a 50 gm sample of the formulation prepared in Example 12 was added 0.035 gm (0.1%) of aluminum acetylacetonate. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 6-8 hrs. The mixture was allowed to stand until cool and the undissolved solids filtered off by microfiltration at 0.2 μm.
Example 18
[0045] To a 50 gm sample of the formulation prepared in Example 12 was added 0.035 gm (0.1 %) of barium acetylacetonate. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 6-8 hrs. The mixture was allowed to stand until cool and the undissolved solids filtered off by microfiltration at 0.2 μm.
Example 19
[0046] To a 50 gm sample of the formulation prepared in Example 12 was added 0.035 gm (0.1%) of calcium acetylacetonate. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 6-8 hrs. The mixture was allowed to stand until cool and the undissolved solids filtered off by microfiltration at 0.2 μm.
Example 20
[0047] To a 50 gm sample of the formulation prepared in Example 12 was added 0.035 gm (0.1%) of zinc acetylacetonate. The mixture was rolled on a roller mill under an infrared heat lamp at 40-50° C. for 6-8 hrs. The mixture was allowed to stand until cool and the undissolved solids filtered off by microfiltration at 0.2 μm.
Example 21
[0048] The formulations prepared in Examples 7-9 and 14-16 were coated onto PET films using a 20 or 40 μm Myers rod and dried in a hot air oven at 100° C. over to prepare dry film resist samples of each example.
Example 22
[0049] The formluations prepared in Examples 14 and 15 were coated or laminated onto aluminum deposited glass substrates and processed as in Example 5. Both examples were found to be far superior to those materials tested in Example 5.
Example 23
[0050] The dry film resists from Example 21 prepared from the compositions described in Examples 7 and 14-16 were laminated onto structured wafers containing 20 μm aluminum SAW filter arrays and imaged to give nominal 0.75 mm by 1.0 mm resist cavities surrounding each of the filter arrays. The wafers were then further cured at 125 to 200° C.
Example 24
[0051] The substrate wafers prepared in Example 23 were then tested under unbiased JEDEC Standard 22-A101-B HAST conditions of 85° C., 85% relative humidity for 100 hours. The wafers prepared from films made from Examples 14-16 were found to be corrosion-free upon microscopic examination. Example 16 also passed 200 hr testing.
Example 25
[0052] Additional SAW device wafers prepared from Example 23 dry films prepared from the compositions described in Examples 15 and 16 were further subjected to additional pressure cooker tests at 131 ° C., 100% relative humidity for 100 hrs and were also found to be corrosion-free by microscopic examination.
Example 26
[0053] Silicon wafers with a coating of 5000 Å of Al/Cu 1% on 100 Å Ti were etched to generate nominal 10 to 50 μm line/space patterns in the Al/Cu as well as 500×500 μm square pads. The patterned metal wafers were then spin coated with SU-8 3000 Resist as described in Example 1 with a total chlorine content of approximately 1000 ppm and compositions from Examples 12 and 18 with total chlorine contents of 20-30 ppm. The wet films were dried by baking at 95° C. for 15 to 20 min resulting in uniform 25 μm thick coatings. The dried coatings were then exposed, post exposure baked and developed to generate 750×750 μm resist pads separated by 325 μm open streets. The wafers were next baked at 150° C. for 30 minutes to cure the films. The wafers were then tested under unbiased JEDEC Standard EIA/JESD22-A101-B HAST conditions of 85° C., 85% relative humidity for 1000 hours. The wafer prepared from films made from SU-8 3000 showed significant corrosion in the open areas in as little as 144 hrs whereas the wafer from Example 12 showed much reduced corrosion and the wafer from Example 18 was found to be corrosion-free upon microscopic examination for the 20 μm and larger lines and nearly corrosion-free for lines less than 10 μm after the 1000 hrs.
Example 27
[0054] Silicon wafers with patterned coatings of 5000 Å of Al/Cu 1% on 100 Å Ti covered with imaged patterns of compositions from Examples 6, 12, and 18 were prepared as in Example 26. The wafers were then tested under unbiased JEDEC Standard JESD22-A102-C accelerated pressure cooker test (PCT) conditions of 121° C., 100% relative humidity for 98 hours. The wafer prepared from films made from Example 6 showed corrosion in the open areas in as little as 24 hrs and significant corrosion after 96 hrs. The wafer from Example 6 showed reduced corrosion and the wafers from Examples 12 and 18 were found to be nearly corrosion-free upon microscopic examination for the 15 μm and larger lines.
Example 28
[0055] Silicon wafers with unpatterned coatings of 5000 Å of Al/Cu 1% on 100 Å Ti, 1000 Å Al with no Ti adhesion layer and 1000 Å of Cu on 100 Å Ta were covered with imaged patterns of a composition from Example 12 were prepared as in Example 26. The wafers were then tested under unbiased JEDEC Standard JESD22-A102-C accelerated pressure cooker test (PCT) conditions of 121° C., 100% relative humidity for 98 hours. All wafers showed severe corrosion in the open areas. The wafer prepared on the Al coating showed initial etching along the edges of the pads and darkening in the covered areas in 24 hrs and loss of approximately 10 μm of metal along the edges and severe darkening over the entire surface after 96 hrs. The wafer prepared on the Al/Cu coating showed reduced corrosion in the covered areas and after 96 hrs only initial attack could be seen along the edges. The wafer on the Cu coating was found to be nearly corrosion-free under the pad upon microscopic examination.
Example 29
[0056] Silicon wafers with patterned coatings of 1000 Å Al with no Ti adhesion layer were covered with imaged patterns of compositions from Examples 6, 12, 18 and 19 were prepared as in Example 24. The wafers were then tested under unbiased JEDEC Standard JESD22-A102-C accelerated pressure cooker test (PCT) conditions of 121° C., 100% relative humidity for 48 hours. The wafer prepared from films made from Example 6 showed corrosion in the open areas. The wafer from Examples 12 showed almost no corrosion and the wafers from Examples 18 and 19 were found to be nearly corrosion-free as could be determined by the test method upon microscopic examination for the 15 μm and larger lines. | This invention relates to the need to improve the corrosion resistance of very low total chlorine epoxy resins which contain very low contents of organically bound chlorine. The invention relates to the improvement of corrosion resistance of such epoxy resins for electronic applications by the addition of specific additives acceptable to the electronics industry. The use of these low chlorine resins in combination with said additives has been shown to be corrosion-free on highly corrosive surfaces such as aluminum and copper, which are frequently encountered in electronic applications. | 2 |
FIELD OF THE INVENTION
This application relates to the novel compound discorhabdin D and compositions containing such compound as an active ingredient. More particularly, the invention concerns the new biologically active compound discorhabdin D, pharmaceutical compositions containing same, methods of producing the compound and compositions and method of using them.
BACKGROUND OF THE INVENTION
Considerable research and resources have been devoted to oncology and antitumor measures including chemotherapy. While certain methods and chemical compositions have been developed which aid in inhibiting, remitting or controlling the growth of tumors, new methods and antitumor chemical compositions are needed.
It has been found that some natural products and organisms are potential sources for chemical molecules having useful biological activity of great diversity. Marine sponges have proved to be such a source and a number of publications have issued disclosing organic compounds derived from marine sponges including Scheuer, P. J. Ed., Marine Natural Products, Chemical and Biological Perspectives; Academic Press, New York, 1978, Vol. I, pp 175-240; Faulkner, D. J., Natural Products Reports 1987, 4, 539-576 and references cited therein; Uemura et al., J. Am. Chem. Soc., 1985, 107, 4796-4798; Minale, L., et al., Fortschr. Chem. org. Naturst. 1976, 33, 1-72.
Discorhabdin compounds related to those of this invention have been produced from marine sponges as disclosed in U.S. No. 4,731,366 and have been discussed in various publications including:
Perry, N. B., et al., J. Org. Chem. 1986, 51, 5476; Blunt, J. W., et al., J. Nat. Prod. 1987, 50, 290; Munro, M. H. G., et al., Bioorganic Marine Chemistry; Scheuer, P. J., Ed.; Verlag Chemie: Heidelberg, 1987, Vol. 1, Chapter 4; Kobayashi, J., et al., Tetrahedron Letters 1987, 28, 4939; Perry, N. B., et al., Tetrahedron 1988, 44, 1727, Perry N. B., et al., J. Org. Chem. 1988, 53, 4127 and Cheng et al., J. Org. Chem. 1988, 53, 4610.
This present invention, utilizing sponges as a source material and supplemented by specific production methods, has provided the art with a new biologically active compound and new pharmaceutical compositions useful as antitumor agents.
Other advantages and further scope of applicability of the present invention will become apparent from the detailed descriptions given herein; it should be understood, however, that the detailed descriptions, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent from such descriptions.
SUMMARY OF THE INVENTION
The objects of the invention are accomplished by the provision of a novel, biologically active compound that has a structure according to the formula: ##STR2##
As embodied and fully described herein, the invention also comprises pharmaceutical compositions, e.g., antitumor compositions, containing as active ingredient, an effective amount, e.g., between about 0.1 to 45% by weight based on the total weight of the composition, preferably about 1 to 25% b/w, of the new compound of the invention and a non-toxic pharmaceutically acceptable carrier or diluent.
As embodied and fully described herein, the invention also comprises processes for the production of the new compound and compositions of the invention and methods of use thereof, e.g., methods of inhibiting tumors in a mammal and therapeutic methods for treating cancerous cachexia.
In accordance with the invention, methods for inhibiting tumors in a host comprise contacting tumor cells with an effective amount of the new pharmaceutical compositions of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A more complete understanding of the invention can be obtained by reference to preferred embodiments of the invention which are illustrated by the following specific examples of the new compound, compositions and methods of the invention. It will be apparent to those skilled in the art that the examples involve use of materials and reagents that are commercially available from known sources, e.g., chemical supply houses, so no details are given respecting them.
One method of preparation of the new compound of the invention involves extraction from marine sponge species of the genus Latrunculia (family Latrunculiidae, order Hadromerida).
EXAMPLE 1
This example concerns the preparation of the compound 1 of the invention, discorhabdin D, having the structure of the formula: ##STR3##
Specimens of marine sponge L. brevis were collected by SCUBA at depths of about 30 m from the Sugar Loaf Islands, Taranaki, New Zealand. Voucher specimens 5NP3-1 and 5NP5-7 have been deposited in the University of Canterbury Marine Collection at Christ-church, New Zealand.
The collected sponge specimens were blended and extracted with MeOH and MeOH/toluene (3:1) to give, after removal of solvents, a green gum. This was partitioned on a reverse phase (RP) column to give a combined fraction containing largely discorhabdin A 2 (see U.S. Pat. No. 4,731,366).
Preparation RPLC [Merck Lobar RP-8 column, 310×25 mm; 4 mL/min MeOH/H 2 O (with 0.05% CF 3 COOH) (3:7); 254 nm detectional] on a subsample gave initially 1 followed by 2. Further preparative RPLC gave pure 1.
Discorhabdin D was characterized as its hydrochloride salt, a deep green solid, mp>360° C.; [] D 0, [] 578 -45, [] 546 -160 (c 0.15, MeOH).
HRFABMS: MH + found 336.08208, calcd for C 18 H 14 N 3 O 2 S 336.08069. The compound revealed the following spectral data:
UV(MeOH): 248 nm (log 4.35), 281(4.15), 320(3.93), 395(3.95), 584(2.84). UV(MeOH/KOH): 262 nm (log 4.49), 290(4.19), 368(3.98).
IR: 3700-2300, 1650, 1620, 1550, 1525, 1490, 1410, 1310 cm -1 .
1 H NMR (CD 3 OD): 7.10(d, J=1.0 Hz, H14), 6.07(t, 0.8, H4), 5.60(dd, 1.4, 3.4, H8), 4.35(t, 2.8, H2), 4.0(ddd, 3.3, 7.6, 14.3, H17), 3.9(ddd, 6.8, 12.6, 14.3, H17.), 3.2(dddd, 1.1, 7.8, 12.5, 16.9, H16), 3.1(ddd, 3.2, 7.2, 16.6, H16), 2.91(dd, 2.8, 13.5, H1R), 2.80(dd, 3.6, 11.9, H7), 2.64(dd, 1.3, 12.1, H7), 2.58(dd, 3.1, 13.3, H1S).
1 H NMR ([CD 3 ] 2 SO): 7.37(s, H14), 6.22(s, H4), 5.79(s, H8), 4.47(s, H2), 13.45(s, NH13), 10.8(s, NH9), 4.13(m, H17), 3.92(m, H17), 3.15(m, H16), 3.02(d, 12.8, H1R), 2.65(d, 12.8, H7), 2.55(d, 12.8, H1S).
13 C NMR ([CD 3 ] 2 SO): 183.08(s, C3), 173.14(s, C5), 166.47(s, C11), 147.84(s, C10 or C19), 145.90(s, C19 or C10), 127.00(d, 1 J CH =190 Hz, C14), 123.69(s, C12 or C21) 121.50(s, C21 or C12), 117.71(s, C15), 112.43(d, 168, C4), 99.64(s, C20), 62.79(d, 169, C8), 62.26(d, 159, C2), 51.24(t, 145, C17), 41.19(s, C6), 38.59(t, C7), 30.27 (t, 137, C1), 19.49(t, 134, C16).
The structure as established by this spectral data and as given by the above formula, although based on the same ring system as discorhabdin C, possesses two further heterocyclic rings to give a total of seven interlocking rings (four heterocyclic and one spiro) and seven double bonds. high resolution FABMS established a composition of C 18 H 14 N 3 O 2 S for MH + of discorhabdin D.
In-Vivo Assay For Antitumor Activity
The following procedure was used for the In-Vivo assay of discorhabdin D for P388.
P388 leukemia was maintained by serial passage in DBA/2 mice. To assay antitumor activity of Discorhabdin D, tumors were established (10 6 cells/0.1 ml) by injection in the i.p. cavity of BDF1 mice. Mice were randomized on day 1 into groups of six mice since bacteriological check of tumor was negative. Test materials were dissolved or suspended in sterile 0.98% NaCl solution with the aid of absolute ethanol and "Tween-80", then administered ip, qD1-9, in a volume of 0.5 ml/mouse. Mice were weighed on days 1 & 9 to provide evidence of toxicity and deaths were recorded daily. Each test included appropriate numbers of untested control mice, one-dose level of the positive reference compound 5-fluorouracil and test material (four dose levels each). Test material were prepared fresh on day 1 and administered daily for nine days. Quantity and consistency of test material precluded fresh preparation daily. Doses were derived from prior single treatment acute toxicity assays. The endpoints for therapeutic evaluation were mean and median survival time and long-term survivors on day 30. A 25% percent increase in life span (%ILS) was considered evidence of significant activity.
The following table reports the in vivo antitumor assay results for dischorhabdin D.
TABLE______________________________________Dose mg/kg Treatment (days) Survival % T/C______________________________________40 1-1 7720 1-9 13210 1-9 123 5 1-9 118______________________________________
It is apparent from the in vivo testing and results reported in the table that the compound of the invention is effective for inhibiting or destroying tumors and therefore in controlling diseases caused by or related to such tumors, e.g., cancerous cachexia. | A new biologically active compound discorhabdin D, pharmaceutical compositions containing same, methods of producing the compound and compositions and methods of using them are disclosed. The new compound, discorhabdin D, has the structure: ##STR1## | 2 |
FIELD OF THE INVENTION
[0001] This invention relates to monitor systems and, in particular embodiments, to devices and methods for operation of a sensor to determine a characteristic of a body.
BACKGROUND OF THE INVENTION
[0002] Over the years, bodily characteristics have been determined by obtaining a sample of bodily fluid. For example, diabetics often test for blood glucose levels. Traditional blood glucose determinations have utilized a painful finger prick using a lancet to withdraw a small blood sample. This results in discomfort from the lancet as it contacts nerves in the subcutaneous tissue. The pain of lancing and the cumulative discomfort from multiple needle pricks is a strong reason why patients fail to comply with a medical testing regimen used to determine a change in characteristic over a period of time. Although non-invasive systems have been proposed, or are in development, none to date have been commercialized that are effective and provide accurate results. In addition, all of these systems are designed to provide data at discrete points and do not provide continuous data to show the variations in the characteristic between testing times.
[0003] A variety of implantable electrochemical sensors have been developed for detecting and/or quantifying specific agents or compositions in a patient's blood. For instance, glucose sensors have been developed for use in obtaining an indication of blood glucose levels in a diabetic patient. Such readings are useful in monitoring and/or adjusting a treatment regimen which typically includes the regular administration of insulin to the patient. Thus, blood glucose readings improve medical therapies with semi-automated medication infusion pumps of the external type, as generally described in U.S. Pat. Nos. 4,562,751; 4,678,408; and 4,685,903; or automated implantable medication infusion pumps, as generally described in U.S. Pat. No. 4,573,994, which are herein incorporated by reference. Typical thin film sensors are described in commonly assigned U.S. Pat. Nos. 5,390,671; 5,391,250; 5,482,473; and 5,586,553 which are incorporated by reference herein, also see U.S. Pat. No. 5,299,571. However, the monitors for these continuous sensors provide alarms, updates, trend information and require sophisticated hardware to allow the user to program the monitor, calibrate the sensor, enter data and view data in the monitor and to provide real-time feedback to the user. This sophisticated hardware makes it most practical for users that require continuous monitoring with feedback to maintain tight control over their conditions. In addition, these systems require the user to be trained in their use, even if to be worn for short periods of time to collect medical data which will be analyzed later by a doctor.
[0004] Doctors often need continuous measurements of a body parameter over a period of time to make an accurate diagnosis of a condition. For instance, Holter monitor systems are used to measure the EKG of a patient's heart over a period of time to detect abnormalities in the heart beat of the patient. Abnormalities detected in this manner may detect heart disease that would otherwise go undetected. These tests, while very useful are limited to monitoring of bio-mechanical physical changes in the body, such as a heart beat, respiration rate, blood pressure or the like.
[0005] Electrochemical sensors typically have a well-defined finite time of use. Contributing to the finite life is the consumption or reaction of chemical reagents that allow the sensor to detect the desired agents and compositions. Upon consumption of the sensor reagents it is possible to get spurious or inaccurate readings from a sensor. It is therefore undesirable and even potentially dangerous to use a sensor beyond its designed lifetime. Despite the known dangers, there are documented cases of sensors being used well beyond their design lifetime. In order to provide accurate data and optimized care, it would be beneficial to have a sensor capable of turning itself off after a specified design lifetime has elapsed.
SUMMARY OF THE DISCLOSURE
[0006] In one embodiment a monitor system to record a characteristic of a user is disclosed. The monitor system includes a sensor to produce signals indicative of a glucose characteristic measured in the user. The sensor includes a connector with a plurality of contacts where at least two of the contacts being shorted by a fuse trace. The system further includes an electronics package that includes a package housing that contains, a battery, a package port interfaced with the connector to receive signals from the sensor, and a package processor to process the signals from the sensor and store the processed signals in non-volatile memory. Further included in the package housing is a fuse system controlled by the package processor that includes a fuse timer. Wherein the fuse trace is destroyed after the fuse timer reaches a threshold value.
[0007] In another embodiment a monitor system to transmit a real-time characteristic of a user is disclosed. The monitor system includes a sensor to produce signals indicative of a glucose characteristic measured in the user, the sensor having a connector with a plurality of contacts, at least two contacts being shorted by a fuse trace; and an electronics package that includes a package housing, a battery being contained within the package housing, a package port interfaced with the connector to receive the produced signals from the sensor, a package processor to process the produced signals from the sensor and transmit the processed signals via a transmitter, a fuse system controlled by the package processor that includes a fuse timer; wherein the fuse trace is destroyed after the fuse timer reaches a threshold value.
[0008] Other features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, various features of embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] A detailed description of embodiments of the invention will be made with reference to the accompanying drawings, wherein like numerals designate corresponding parts in the several figures.
[0010] FIG. 1 is an exemplary illustration of components of a monitor system, in accordance with embodiments of the present invention.
[0011] FIGS. 2A-2C are exemplary illustrations of placement of a sensor and installation of the electronics package onto the sensor, in accordance with embodiments of the present invention.
[0012] FIG. 3 is an exemplary block diagram illustrating components within the electronics package, in accordance with one embodiment of the present invention.
[0013] FIGS. 4A-4D are exemplary views of the fuse circuit in accordance with embodiments of the present invention.
[0014] FIG. 5A is an exemplary illustration of package port that would receive the connector from the sensor, in accordance with one embodiment of the present invention.
[0015] FIGS. 5B-5D illustrate various embodiments of detail of the recorder port, in accordance with embodiments of the present invention.
[0016] FIG. 6 is an exemplary flow chart illustrating operations to initiate a sensor with a fuse, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0017] As shown in the drawings for purposes of illustration, the invention is embodied as a component within a subcutaneous implantable analyte sensor set that provide continuous data of the sensor readings to a portable infusion system. In some embodiments the sensor data is recorded into memory integrated into an electronics package that also provides power and wireless communication capability to the sensor. In other embodiments the sensor transmits sensor readings to an infusion pump that can include memory to store the sensor readings. The recorded sensor readings or data can later be downloaded or transferred to a computing device to determine body characteristic data based on the data recording over the period of time. In embodiments of the present invention, the analyte sensor set and monitor system are for determining glucose levels in the blood and/or bodily fluids of the user without the use of, or necessity of, complicated monitoring systems that require user training and interaction. However, it will be recognized that further embodiments of the invention may be used to determine the levels of other analytes or agents, characteristics or compositions, such as hormones, cholesterol, medications concentrations, viral loads (e.g., HIV), or the like. In other embodiments, the monitor system may also include the capability to be programmed to record data at specified time intervals. The monitor system and analyte sensor are primarily adapted for use in subcutaneous human tissue. However, still further embodiments may be placed in other types of tissue, such as muscle, lymph, organ tissue, veins, arteries or the like, and used in animal tissue. The analyte sensors may be subcutaneous sensors, transcutaneous sensors, percutaneous sensors, sub-dermal sensors, skin surface sensors, or the like. Embodiments may measure and record sensor readings on an intermittent or continuous basis.
[0018] FIG. 1 is an exemplary illustration of components within a monitor system 100 , in accordance with embodiments of the present invention. The sensor 102 is shown from an exemplary top view as if it has been inserted into a patient. In one embodiment the sensor 102 utilizes an electrode-type sensor while in alternative embodiments, the sensor 102 may use other types of sensors, such as chemical based, optical based or the like. In further alternate embodiments, the sensor 102 may be of a type that is used on the external surface of the skin or placed below the skin layer of the user or placed in the blood stream of the user. Other embodiments of a surface mounted sensor would utilize interstitial fluid harvested from the skin.
[0019] In some embodiments, the sensor 102 is an assembly commonly known as a “sensor set” that includes, but it not limited to the connector 104 , sensor adhesive (not shown) covered by an adhesive backing 106 , an introducer needle (not shown in FIG. 1 ), a sensing portion of the sensor to be placed in a body (not shown), and a mounting base 105 . In one embodiment the connector 104 is integrally injection molded from plastic with the mounting base 105 . The connector 104 further includes electrical contacts that interface with contacts on the sensor. On a side opposite that shown in FIG. 1 , the adhesive is applied to the mounting base 105 and the adhesive backing 116 is further applied over the adhesive.
[0020] An electronic package 108 is also included in the monitor system 100 . The electronics package 108 includes a package housing 109 with a package port 110 . The package port 110 is designed to couple with the electrical contact on the connector 104 thereby providing power and other electrical interfaces between the electronics package 108 and the sensor 102 . In one embodiment the electronics package further includes a power source, processor and transmitter within the package housing 109 . The power source provides power for the processor and transmitter and when coupled to the connector 104 , further powers the sensor 102 . In such an embodiment signals generated by an installed sensor can be processed via the processor and transmitted to another device such as, but not limited to infusion pump 112 . In other embodiments, the electronics package 108 includes at least a power source, processor, transmitter along with memory and a receiver. In these embodiments sensor signals from an installed sensor can be stored to memory within the package housing 109 and periodically transmitted to the infusion pump 112 or other devices configured to communicate with the electronics package 108 . Additionally, the inclusion of the receiver within the electronics package would enable two-way communication between other devices and the electronics package 108 .
[0021] The inclusion of memory within the electronics package 108 can enable the combined electronics package 108 and sensor 102 to be used as a Holter-type recording device that can use the package port 110 to interface with either the sensor 102 or a docking station (not shown) that is further connected to a computer of tablet computing device. When used as a recording device the combined electronics package 108 and sensor 102 have the capability to record and store data as it is received from the sensor 102 . When the electronics package 108 is coupled to a docking station the data stored on the memory of the electronics package 108 can be transferred to networked or local data storage and analyzed using general computing processors such as desktops, laptops, notebooks, netbooks, tablets, or handheld computing devices such as, but not limited to smart phones and the like. To enable data transfer through the dock, the dock may further include a data transfer cable such as, but not limited to USB or Thunderbolt or Ethernet directly coupled to a computing device.
[0022] The infusion pump 112 included in the monitor system 100 includes a tubing 120 that is in connected to a reservoir 118 within the infusion pump 112 . Other characteristics of the infusion pump include a display 114 and a user interface 116 . In some embodiments the display 114 is a touchscreen thereby making the display 114 an integrated component of the user interface 116 . The infusion pump 112 can further include a radio transmitter and receiver that enables wireless communication. In some embodiments the radio transmitter is a standard off the shelf BLUETOOTH radio that includes the BLUETOOTH LOW ENEGRY profile. In other embodiments a custom secure radio transmission system is used. The radio transmitter within the infusion pump 112 enables wireless transmission with the electronics package 108 thereby allowing sensor data to shown on the display 114 .
[0023] Transmission of sensor data to the infusion pump 112 further enables real-time glucose monitoring which can further enable low-glucose suspend functionality. In these embodiments if the sensor data indicates a blood sugar level below a specified threshold, the infusion pump 112 can suspend delivery of basal insulin. In some embodiments the raw sensor data measured by the sensor 102 is manipulated or processed using the processor within the electronics package 108 to determine sensor data from interstitial fluid that corresponds to a blood glucose level. In still other embodiments, the electronics package 108 transmits the raw sensor data to the insulin pump 112 where the raw sensor data is processed to correspond to a blood glucose level. In still other embodiments, the electronics package 108 transmits both the raw sensor data and a first calculated blood glucose level to the insulin pump. In these embodiments the insulin pump can then use a different algorithm to calculate a second blood glucose level from the raw sensor data. The second blood glucose level then being used in conjunction with the first blood glucose level to determine a third calculated blood glucose level.
[0024] Further description regarding the sensor and associated sensor set can be found in U.S. Pat. No. 6,248,067, entitled A NALYTE SENSOR AND HOLIER-TYPE MONITOR SYSTEM AND METHOD OF USING THE SAME , U.S. Pat. No. 5,586,553, entitled T RANSCUTANEOUS SENSOR INSERTION SET , and U.S. Pat. No. 5,594,643, entitled D ISPOSABLE SENSOR INSERTION ASSEMBLY , all of which is herein incorporated by reference.
[0025] FIGS. 2A-2C are exemplary illustrations of placement of a sensor 102 and installation of the electronics package 108 onto the sensor 102 , in accordance with embodiments of the present invention. FIG. 2A illustrates a sequence of typical steps used to place the sensor 102 within interstitial fluid of a patient. The leftmost panel of FIG. 2A is illustrative of using an inserter 200 to assist in the installation or placement of the sensor 102 . Commonly, inserters 200 are customized to accommodate a specific type of sensor 102 . For additional information regarding inserter 200 please see U.S. patent application Ser. No. 10/314,653 filed on Dec. 9, 2002, entitled I NSERTION DEVICE FOR INSERTION SET AND METHOD OF USING THE SAME , U.S. Pat. No. 6,607,509, entitled I NSERTION DEVICE FOR AN INSERTION SET AND METHOD OF USING THE SAME , and U.S. Pat. No. 5,851,197 entitled I NJECTOR FOR A SUBCUTANEOUS INFUSION SET , all of which are herein incorporated by reference.
[0026] The middle panel of FIG. 2A is an illustration showing the removal of the adhesive backing 106 to expose an adhesive that enables adhesion of the sensor 102 to skin 202 of a patient. The rightmost panel of FIG. 2A is an illustration that depicts the removal of an introducer needle 204 that is used during the placement of the sensor 102 . FIG. 2B is an exemplary illustration showing the installation of the electronics package 108 onto the sensor 102 . Direction arrows D 2 indicate that the electronics package 108 is pushed onto the sensor 102 that was adhered to the patient, as shown in the middle panel of FIG. 2A . In some embodiments, it is desirable to wait a predetermined period of time before installing the electronics package 108 onto the sensor 102 . For example, it may be advantageous to wait for up to 15 minutes for the sensor 102 to be properly hydrated or wetted by the patient's interstitial fluid before attaching the electronics package 108 . In other embodiments it may take longer or less time before is sensor is considered properly hydrated. Being able to detect if an installed sensor 102 is properly hydrated can be used by a practitioner to help determine if the sensor was properly installed into the interstitial fluid. In other embodiments there is no minimum time required before attaching the electronics package 108 to the sensor 102 . In still more embodiments, the sensor 102 need not be hydrated before the electronics package 108 is connected. And in additional embodiments, the electronics package 108 may be integrated with the sensor before the sensor is inserted into a user. Once the electronics package 108 is coupled with the sensor 102 some embodiments initialize the sensor based on algorithms stored in the electronics package. During the initialization process algorithms can determine if the sensor is properly hydrated and will most likely function as designed. In other embodiments initialization of the sensor is not required.
[0027] As illustrated in FIG. 2C , some embodiments of the electronics package 108 include a feedback indicator 206 . In one embodiment the feedback indicator 206 is a light emitting diode (LED) that can be seen through a translucent or semi-translucent housing. In other embodiments, different light elements can be used, such as, but not limited to incandescent lights, fluorescent lights, organic light emitting diodes (OLED) or the like. In still other embodiments, the feedback indicator 206 can be an audible tone or a vibration alarm similar to those in mobile phones. In embodiments with the feedback indicator 206 , the electronics package 108 can provide feedback regarding the hydration level of a connected sensor. For example, the recorder includes hardware and software that can determine if the sensor 102 is properly hydrated. The feedback indicator 206 can help a practitioner by narrowing the type of troubleshooting that needs to be performed. For example, the feedback indicator 206 can be programmed to flash a specific sequence or color to indicate that the sensor 102 is properly hydrated. Similarly, the feedback indicator 206 can be programmed to flash a different sequence or color to indicate that the sensor is not properly hydrated. In other embodiments, the feedback indicator 206 can further be programmed to flash a particular sequence or color that indicates to a practitioner that the electronics package 108 is not fully charged or even that data needs to be transferred from the electronics package 108 before additional data can be recorded. The examples provided are not intended to be exhaustive of conditions that can be reported by the feedback indicator 206 . The particular examples provided are intended to be exemplary and should not be construed as limiting the scope of the present invention.
[0028] FIG. 3 is an exemplary block diagram illustrating components within the electronics package 108 , in accordance with one embodiment of the present invention. A power supply 212 connected to power management 214 is found within the package housing 109 of the electronics package 108 . In some embodiments the power supply 212 is a battery assembly that uses a rechargeable battery chemistry to provide power to the electronics package 108 . In one embodiment the power supply 212 is made up of lithium ion battery cells. However, it is understood that alternate battery chemistries may be used, such as nickel metal hydride, alkaline or the like. Similarly, various embodiments can use a single battery cell for a shorter life such as for a single-use disposable unit while other embodiments use multiple battery cells that enable longer and/or reusable/rechargeable units.
[0029] In rechargeable embodiments the power management 214 includes circuitry and programming to allow recharging of the power supply 212 via the package port 110 . In some embodiments power management 214 also includes circuitry and programming that enables a low battery warning alarm. In some embodiments the power supply 212 is capable of enabling the electronics package 108 to measure and/or record data for six days with a factor of safety of one additional day. Additionally, after six or seven days of measuring or recording data, the power supply further enables operation of an integrated clock in the electronics package 108 for an additional seven days. Alternative embodiments may provide longer or shorter battery lifetimes, or include a power port or solar cells to permit recharging of the power supply 212 .
[0030] The sensor 102 is connected via the connector 104 and the package port 110 to a signal conditioning circuit 202 , such as a potentiostat or the like, in the package housing 109 of the electronics package 108 . The signal conditioning circuit 202 is in turn connected to a current to frequency converter (I to F) 204 . The output of the current to frequency converter 204 is a digital frequency that varies as a function of the sensor signal produced by the sensor 102 . In alternative embodiments, other signals, such as voltage, or the like, may be converted to frequency. In one embodiment, the digital frequency is then counted by a digital counter 206 , and a value from the digital counter 206 is periodically read and stored with an indication of elapsed time, by a microprocessor 208 , into a non-volatile memory 210 . In other embodiments the value from the digital counter 206 is sent to transmitter 211 for transmission to, but not limited to, the infusion pump (not shown). In further embodiments the transmitter 211 additionally functions as a receiver thereby allowing two way communication between the electronics package 108 and the infusion pump.
[0031] In some embodiments, the electronics package 108 provides power to drive the sensor 102 via the package port 110 and the connector 104 . Power from the electronics package 108 may also be used to speed initialization of the sensor 102 , when it is first placed under the skin. The use of an initialization procedure can result in a sensor 102 providing stabilized data in an hour or less compared to requiring several hours before stabilized data is acquired without using an initializing procedure. One exemplary initialization procedure uses a two step process. First, a high voltage (preferably between 1.0-1.2 volts—although other voltages may be used) is applied to the sensor 102 for one to two minutes (although different time periods may be used) to initiate stabilization of the sensor 102 . Then, a lower voltage (preferably between 0.5-0.6 volts—although other voltages may be used) is applied for the remainder of the initialization procedure (typically 58 minutes or less). The initialization procedure described above is exemplary and other initialization procedures using differing currents, voltages, currents and voltages, different numbers of steps, or the like, may be used. In all embodiments the microprocessor 208 is further coupled to a fuse circuit 214 . The fuse circuit 214 can be used to help limit the number of uses of the sensor thereby ensuring sensors are not used beyond their expected lifecycle. Use of a sensor beyond its expected lifecycle can lead to erroneous and unreliable readings that may compromise the efficacy of therapy. Additional details regarding the fuse circuit will be discussed below.
[0032] FIGS. 4A-4D are exemplary views of the fuse circuit 214 in accordance with embodiments of the present invention. FIG. 4A illustrates a basic circuit diagram with switch 404 that is controlled by the microprocessor 208 . The charging of capacitor 402 would likewise be controller by the microprocessor 208 . Upon closing the switch 404 the capacitor 402 would discharge with enough energy to break fuse 400 . FIG. 4B illustrates elements of the fuse circuit that are implemented on the connector 104 from FIG. 1 . As illustrated, fuse 400 is made by narrowing material that also makes up sensor detection pads 406 a and 406 b . The sensor detection pads 406 a and 406 b being shorted by fuse 400 serve as a switch that signals to the electronics package that a sensor is plugged in. In some embodiments, upon detecting the sensor, the electronics package initiates a timer for a first specified time. Once the first specified time has elapsed the capacitor 402 is charged and discharged into the shorted sensor detection pads 406 a and 406 b thereby breaking the fuse 400 . In some embodiments the sensor signals can continue until the sensor is disconnected or until a second specified time has elapsed. The breaking of the short between sensor detection pads 406 a and 406 b can ensure that the sensor is only used once as the microprocessor can perform a check for shorted sensor detection pads 406 a and 406 b upon initialization of a sensor.
[0033] FIGS. 4C and 4D are illustrations of a first side 408 and a second side 410 of the connector 104 , in accordance with an embodiment of the present invention. The first side 408 includes the previously discussed sensor detection pads 406 a and 406 b along with fuse 400 . Located between the sensor detection pads 406 a and 406 b is an electrical contact for a second working electrode 418 . On the second side 410 of the connector 104 are the contacts for a counter electrode 412 , a first working electrode 414 and a reference electrode 416 . The relative position of the contacts should not be construed as limiting as the various locations can vary depending on how traces are made on the sensor.
[0034] FIG. 5A is an exemplary illustration of package port 110 that would receive the connector 104 from the sensor, in accordance with one embodiment of the present invention. The embodiment shown in FIG. 5A is a 10-pin connector that enables communication with the contact pads discussed in FIGS. 4A-4D while also providing additional electrical contacts for power, transmitters and receivers. The particular embodiments discussed in detail below should not be construed as limiting. Other embodiments can use various port and pin configurations. In still other embodiments, additional or fewer electrical contacts may be implemented on both the package port and the connector to enable or disable various sensor features. As shown in FIG. 5A pins 506 a and 506 b are designed to interface with sensor detection pads 406 a and 406 b . Likewise, second working electrode pin 518 interfaces with second working electrode contact 418 . Counter pin 512 , first working electrode pin 515 and reference pin 516 interface respectively with counter contact 412 , first working electrode contact 415 and reference contact 416 . Further included are ground pin 502 , charge pin 504 , transmitter pin 510 and receiver pine 516 . For single-use embodiments, the charge pin 504 can be omitted.
[0035] FIGS. 5B-5D illustrate various embodiments of detail 520 of the recorder port 110 , in accordance with embodiments of the present invention. Detail 520 shows top contacts 522 and bottom contacts 524 which together can simply be referred to as “electronics package contacts”. In the embodiment illustrated the electronics package contacts are mounted to a circuit board 526 to which the components described in FIG. 3 are also mounted. The electronics package contacts can be board mounted springs, or simple contact pads, or any other variety of contact that creates a reliable electrical connection.
[0036] The configuration illustrated is intended to be exemplary and should not be construed to be limiting. For example, in alternative embodiments shown in FIG. 5C , rather than a single recorder port 110 ( FIG. 5A ), the sensor 104 could have two separate ports with the first port 550 providing access to top contacts 522 while the second port 552 provides access to bottom contacts 524 . Similarly, other embodiments could use two separate ports while placing the bottom contacts 524 on the same side of the circuit board 526 as the top contacts 522 , as shown in FIG. 5D .
[0037] FIG. 6 is an exemplary flow chart illustrating operations to initiate a sensor with a fuse, in accordance with an embodiment of the present invention. The flow chart begins with START operation 600 followed by operation 602 where the connector for the sensor is inserted into the package port. Operation 604 utilizes the microprocessor within the electronics package to verify a short between the sensor detection pads. Operation 606 initiates a first timer and operation 608 determines if the first timer has reached the predetermined elapsed time. In some embodiments, the first timer allows the sensor to be used for 138 hours. In other embodiments, shorter or longer periods may be used for the first timer depending on the chemistry and configuration of the sensor.
[0038] Operation 610 charges and discharges the capacitor within the fuse circuit to break the fuse and open the short between the sensor detection pads. Operation 612 starts a second timer that is programmed to stop the sensor from functioning after a specific time has elapsed. In one embodiment, the second timer is set to run for six hours. Together with the initial 138 hours, this embodiment results in 144 hours, or six days of sensor use. In other embodiments, six days of sensor use may also be the total number of days of use but various times can be used for the first timer and second timer to ensure the sensor does not cease functioning while a user is asleep. Accordingly, the first time period may be shortened in order to increase the second time period while still having the sensor operate for six days. In some embodiments the first and second timers are countdown timers that count down from the predetermined elapsed time to zero. In other embodiments, the first and second timers count forward until the elapsed time is the same as the predetermined elapsed time. In still other embodiments the first timer is a countdown timer and the second timer counts forward or vice versa. Operation 614 notifies the user via messages displayed on the infusion pump that disconnecting the sensor will permanently terminate use of the sensor. In some embodiments operation 614 further displays the amount of time remaining until the sensor stops functioning on the display of the infusion pump.
[0039] In still other embodiments, the feedback indicator on the electronics package may begin blinking or flashing upon activation of the second timer. In some embodiments the color of the flashing LED of the feedback indicator of the electronics package can change the longer the second timer is running. For example, upon initiation of the second time, the LED may flash a first color such as green. When about half the time of the second timer has elapsed, the LED switches to a second color such as yellow. Finally, when about a quarter of the time for the second timer remains, the LED switches to a third color such as, but not limited to, red. In addition to changes color, in other embodiments the LED feedback indicator on the electronics package can also flash at different rates depending on how much time of the second timer remains. Operation 616 terminates the sensor. In some embodiments the sensor may continue to operate, but signals from the sensor are not processed or transmitted to other devices. In other embodiments sensor functionality is terminated by disconnecting the power supply. Operation 618 ends the process.
[0040] While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention.
[0041] The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | A monitor system to monitor a characteristic of a user is disclosed. A monitor system includes a sensor producing signals indicative of glucose characteristics within the user. The sensor has a connector with a plurality of contacts, at least two contacts being shorted by a fuse trace. The monitor system further includes an electronics package with a package housing. The package housing contains a battery, a package port interfaced with the connector to receive signals from the sensor, and a package processor to process the signals from the sensor. Further included in the monitor system is a fuse system controlled by the package processor that includes a fuse timer, wherein the fuse trace is destroyed after the fuse timer reaches a threshold value. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 60/045,483, filed May 2, 1997.
FIELD OF THE INVENTION
This invention relates to the field of diffraction gratings, and particularly to adjustable and compound diffraction gratings to simplify measurements in multiple spectral passbands.
BACKGROUND OF THE INVENTION
Various designs of micromechanical systems capable of light diffraction have been previously developed for a number of applications. One class of micromechanical diffraction elements, the grating, can be used for various electro-optical applications such as spectroscopy or as spatial light modulators for applications such as display technology and optical signal processing.
A spatial light modulator is presented in U.S. Pat. No. 5,061,049 whereby a reflective element is electrostatically controlled by electrodes to achieve various angles of beam deflection. The primary advantage taught in this patent is the small deflection angle and uniform beam deflection achieved by using two sets of electrodes designated address electrodes and landing electrodes. The landing electrodes minimize the stress to the deflected element. The simple design of the reflective element provides ample means of beam deflection but does not address the diffraction requirements of spectroscopy.
A deformable grating apparatus is presented in U.S. Pat. Nos. 5,459,610 and 5,311,360 both by Bloom et al. The grating apparatus is presented as a means to modulate incident light rays primarily for display technology applications. An array of beams, at initially equal heights and with reflective surfaces, are supported at predetermined fractions of incident wavelength above a similarly reflective base. Below the base is a means of electrostatically controlling the position of the beams by supplying an attractive force which will deflect all of the beams or every other beam to a secondary position. The diffraction of the incident light is dependent upon the position of the reflective beam elements. The primary application of the grating apparatus presented in these prior art patents is as a spatial light valve. Control of the deformable grating apparatus is limited for spectroscopic applications.
OBJECTS OF THE INVENTION
It is an object of the invention disclosed herein to provide a compound diffraction grating developed through microelectromechanical systems (MEMS) processing that can be reconfigured in real time to allow for sequential analysis of multiple passbands thereby simplifying spectroscopic measurements for multispectral analysis.
It is also an object of the invention to provide a reconfigurable compound diffraction grating to enable wavelength tuning in a laser cavity via voltage adjustments to the grating.
SUMMARY OF THE INVENTION
The present invention provides a reconfigurable compound diffraction grating fabricated using MEMS technology. The implementation of this reconfigurable compound diffraction grating in a miniature spectrometer will simplify multispectral analysis measurements.
A common lower electrode is placed beneath selected reflective beam elements to achieve the desired grating configuration (i.e. every other, every third, every fifth, etc.). The same beam elements which have the electrode underneath are elevated above the other beam elements in the grating's initial position. The elevation of periodic selected grating elements is the basis for the design of the compound grating structure, which can be viewed as two gratings superimposed on one another, namely, a lower resolution diffraction grating consisting of only the elevated beams and a higher resolution grating consisting of all of the beams.
All of the beam elements are linked to a common upper electrode. Voltage applied across the upper and lower electrodes creates an electrostatic force that pulls the selected beams down toward the underlying electrode. Changing the vertical position of the selected beams with respect to the other stationary beams presents a different ruling distribution to the incoming radiation. By changing this distribution spacing, the diffracted power among individual diffraction orders of the wavelengths is altered. Controlling the diffracted signal in this way allows for specific diffraction passbands to be fixed on a particular detector or a particular area of a detector.
Therefore a diffraction grating of this design can be sent a series of calibrated voltage pulses to change the ruling distribution of the grating through the desired configurations for complete spectral analysis. These adjustments can be made very rapidly in an automated manner, which significantly simplifies and reduces the time necessary for complete spectral analysis previously achieved by mechanical movement of the diffraction grating, or by interchanging several gratings.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the invention believed to be novel are set forth in its associated claims. The invention, however, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawing(s) in which:
FIG. 1 is a two dimensional top view of the reconfigurable compound diffraction grating.
FIG. 2 is a two dimensional side view of a deflectable beam and a stationary beam in the initial position of the compound diffraction grating.
FIG. 3 is an exploded isometric, cutaway view of the reconfigurable compound diffraction grating in an initial position.
FIG. 4 is an exploded isometric, cutaway view of the reconfigurable compound diffraction grating in a secondary position.
FIG. 5 is a schematic cross sectional view of the reconfigurable compound diffraction grating with every other beam being a deflectable beam with an associated lower electrode extension beam.
FIG. 6 is a schematic cross sectional view of the reconfigurable compound diffraction grating with every third beam being a deflectable beam with an associated lower electrode extension beam.
FIG. 7 is a schematic cross sectional view of the reconfigurable compound diffraction grating with every fifth beam being a deflectable beam with an associated lower electrode extension beam.
FIGS. 8a and 8b is a representation of light diffracting from the compound grating in the initial undeflected and secondary deflected positions.
FIG. 9 is a top view of an example of an array of reconfigurable compound diffraction gratings.
DETAILED DESCRIPTION
The primary basic function of a diffraction grating in any application is to separate incident light by wavelength. The general operation of a diffraction grating is sensitive to the wavelength of incident light and input angle and will diffract specific wavelengths of light at specific angles based on the grating design.
The reconfigurable, compound diffraction grating 1 is shown from a top view in FIG. 1, and from a cutaway isometric view in FIG. 3. A base 100, typically made of silicon, supports a frame 102. A lower electrode lead 104 lies on the base 100, and runs parallel to and below the frame 102, as shown in FIG. 3. An upper electrode lead 106, runs through two corners of the frame 102 along the top surface 302 of said frame 102, generally perpendicular to the extension of a set of diffraction beams 108 supported at their ends by the frame 102.
This set of beams 108 comprises both stationary beams 210 and deflectable beams 212. The planes of the beams 108, run substantially parallel to each other and substantially perpendicular to the sides of the frame 102, by which they are supported. The set of beams 108, are of substantially uniform thickness, width and length. The beams 108, are much longer than they are wide and thick. The beams 108, are spaced along the frame 102, at periodic intervals. Both the base 100, and the top surface of the set of beams 108, are of a reflective nature.
The upper electrode lead 106, the top surface 302 of the frame 102, and the set of beams 108 are all electrically connected, and together comprise an upper electrode. The lower electrode lead 104 and a series of lower electrode extension beams 214 are all electrically connected, and together comprise a lower electrode. The frame 102, which is an electrical insulator, enables the introduction of voltage differentials between the upper electrode comprising 106, 302 and 108, and the lower electrode comprising 104 and 214.
The deflectable beams 212, can be identified as those in the set of beams 108, which have the lower electrode extension beams 214, running underneath them. Also, in the initial undeflected position shown in FIG. 3, the deflectable beams 212, are in an elevated plane above the stationary beams 210, although remaining generally parallel. The relative parallelism is achieved by the excessive length of all of the beams 108 as compared to their length and width. This elevation of the deflectable beams 212, is a key feature in the design of the reconfigurable compound diffraction grating 1, which can be viewed as the superposition of two grating structures. The series of deflectable beams 212, comprise a low resolution grating secondary to the higher resolution primary grating consisting of the full set of beams 108.
The diffraction of incident light by the reconfigurable compound diffraction grating is controlled by manipulating the vertical position of particular individual beams in the set of beams 108, and in particular, by changing the vertical position of the deflectable beams 212 while leaving unaltered the vertical position of the stationary beams 210.
FIG. 2 shows a cutaway side view of the interior of the reconfigurable compound diffraction grating in which the vertical elevation of the plane of the deflectable beams 212, over the plane of the stationary beams 210 is evident. One of the lower electrode extension beams 214 is shown lying on the base 100, immediately beneath one of the deflectable beams 212. This deflectable beam 212 is shown in its initial position. As seen in FIG. 2, the majority of the top surface of the deflected deflectable beam 212, remains substantially parallel to an adjacent stationary beam 210. Application of a voltage differential applied between the deflectable beams 212, and the lower electrode extension 214, would result in a deflection of the beams 212, in which they would approach the plane of the stationary beams 210. Of course, application of different voltages would result in different degrees (distances) of deflection.
FIG. 3 is a cutaway isometric view of the reconfigurable compound diffraction grating in an initial, undeflected position. This view shows exactly how the lower electrode extension beams 214, project along the base 100 from the lower electrode lead 104, and how the deflectable beams 212 are positioned directly above the lower electrode extension beams 214 so that they may be deflected when a voltage differential is applied between the upper and lower electrodes generally.
FIG. 4 is a similar cutaway isometric view of the reconfigurable compound diffraction grating, with the deflectable beams 212 depicted at a deflected position in which the deflectable beams 212, are in the same plane as the stationary beams. Applying a voltage differential across the two (upper and lower) electrodes via the upper and lower electrode leads 106 and 104, respectively, causes the deflectable beams 212 to move towards the lower electrode extension beams 214. The deflection of the deflectable beam 212, is proportional to the voltage applied to the lower electrode lead 104, and therefore to the lower electrode extension beam 214 electrically connected thereto.
The upper electrodes (comprising 106, 302, and 108 (i.e., 210/212)) are typically fabricated as a unit whole with the rest of the grating structure typically of a material such as silicon. No shielding is necessary between the stationary beams, 210, and the adjacent deflectable beams, 212, since the aspect ratio of the set of beams, 108, is such that voltage applied to the lower electrode lead 104, and therefore to the lower electrode extension beam, 214, is enough to only deflect the deflectable beam, 212.
For descriptive purposes thus far, the stationary beams 210, and the deflectable beams 212 have been shown alternating every position in the diffraction grating, which is represented in the cross sectional schematic view of FIG. 5. Alternative configurations of the stationary beams 210, and the deflectable beams 212, may be desired depending on the specific application of the diffraction grating. Although the diffraction of the incoming light is altered by changing the vertical position of the deflectable beams 212, and thereby changing the vertical spacing between the stationary beams 210, and the deflectable beams 212, alternative configurations of the stationary beams 210, and the deflectable beams 212 are beneficial for various parts of the spectrum. In addition, such configurations can be determined based on the resolution requirements of the secondary grating structure that consists of the deflectable beams 212.
FIG. 6 presents an alternative configuration in which the deflectable beams 212 occupy every third position and the stationary beams 210 occupy the remaining positions. Similarly, FIG. 7 presents another alternative configuration in which the deflectable beams 212 occupy every fifth position and the stationary beams 210 occupy the remaining positions. The alternative configurations are not limited to those shown in FIGS. 5, 6, and 7, and indeed, any repetitive periodic pattern could be incorporated into the grating design and is contemplated by this disclosure and its subsequent associated claims. From these configurations, the diffraction of the incoming light is controlled by the vertical position of the deflectable beams 212.
Using the configuration in which every third beam is deflectable, as presented in FIG. 6, FIGS. 8a and 8b are respective representations of the light diffracted from the reconfigurable diffraction grating 1 in the initial position (FIG. 8a) and as the beams are deflected to the secondary position where the deflected and stationary beams are aligned (FIG. 8b). That is, FIG. 8a represents the initial position of FIG. 3, and FIG. 8b represents the secondary position of FIG. 4, but with the every-third-beam spacing of FIG. 6. The diffraction is changed when the beams are deflected due to the change in the position of the reflective surface.
FIG. 8a shows the light diffracted from the reconfigurable compound diffraction grating base 100 in the initial position of the configuration of every third beam being deflectable. The secondary diffraction grating consisting of only the deflectable beams 212 causes the diffraction described below as due to 3d spacing. The primary diffraction grating consisting of the entire set of beams 108, accounts for the diffraction described below as due to d spacing. The diffraction generated from impinging light, 818, includes a zero order, 820, a first order (due to 3d spacing where d is beam spacing), 822, a second order (due to 3d spacing), 824 and a third order/first order superposition (due to 3d spacing and d spacing, respectively), 826. FIG. 8b shows the diffraction generated from the grating base 100 when the deflected beams (every third beam configuration) are moved to their secondary position where they are aligned with the undeflected beams. In this configuration only the zero order, 820 and first order (due to d spacing), 826 are present as a result of impinging light, 818. It is important to note that FIGS. 8a and 8b are simply illustrative of how light readings may be taken from this grating, and that many other variations obvious to someone of ordinary skill are possible and clearly within the scope of this disclosure and its associated claims.
The reconfigurable diffraction grating is typically fabricated using MEMS processing. Current MEMS processing techniques are capable of features on the scale of 1-2 microns. The most critical dimension in the operation of the diffraction grating is the width of the beam. The ruling or grating spacing determines the resolution of the grating. With the current feature sizes on the 1-2 micron scale, a grating comparable with a medium resolution (600-1200 grooves/mm) conventional optical grating is produced. This resolution is ideal for the visible and near-infrared region of the electromagnetic spectrum and higher wavelengths, as well. The design of the reconfigurable compound diffraction grating can be scaled to include wider beams and grating spacings to be useful in applications in the infrared region of the electromagnetic spectrum. As the size limitations of the MEMS processing technique decreases, the reconfigurable diffraction grating will be applicable below this wavelength, and it is contemplated that the scaling of the beam width and ruling to such smaller dimensions is fully encompassed by this disclosure and its subsequent associated claims.
The use of such a reconfigurable compound diffraction grating could be incorporated in a miniature spectrometer apparatus, and is part of this disclosure and its associated claims. In miniaturizing a spectrometer setup, size, space and simplicity are critical factors. A grating designed on the scale described above would greatly minimize the space required. Control of the grating would also become simplified and automated by the calibrated voltage sequence applied to change the grating spacing.
The use of such a reconfigurable compound diffraction grating could also find application in the development of a tunable laser cavity as well. Conventional gratings are used in laser cavities to tune the lasers to a specific wavelength, usually by manual rotation. Use of the reconfigurable compound diffraction grating in the tunable laser cavity would simplify control of the wavelength selection to the application of a precalibrated voltage setting and allow for rapid and automated sequencing between lasing lines. This too, is contemplated in the scope of this disclosure and its associated claims.
Presented above is just a single embodiment of the present invention. Alternative embodiments include variations in the configuration of beams that establish the rulings of the diffraction grating. The design presented above can be formed with a variety of beam widths and spacings between the beams, also known as grating spacing. For example, these variations include but are not limited to, beams spaced half a beam width apart, a quarter of a beam width apart, and twice a beam width apart. All such variations, and similar variations, are contemplated by this disclosure and its associated claims.
Another alternative embodiment of the reconfigurable compound diffraction grating includes coating the set of beams 108, the upper electrode lead 106, and the lower electrode lead 104, with a thin film of reflective coating such as gold or aluminum in order to significantly increase the reflectivity and therefore resultant signal strength. Coating the top surface of the set of beams 108, also provides a means of reducing the electrical resistance. This is particularly important in high frequency applications.
Another alternative embodiment of the present invention includes expanding the single diffraction grating presented above to an array of diffraction gratings that would respond to a broader input signal or have a multitude of beam configurations as presented for example in FIGS. 5, 6, and 7 available in one array to a single input signal for parallel processing. One such embodiment is presented in FIG. 9. The design of the reconfigurable compound diffraction grating from FIG. 1 is extended in width and replicated in a 1×5 array of diffraction gratings connected by the common upper electrode lead 106, and a lower electrode lead 104, on a common base 100. The individual frames 102 and set of beams 108, are evident in each array grating element.
Yet another alternative embodiment of this invention is the reconfigurable compound diffraction grating configured with a lower electrode extension beam 214, under every beam in the set of beams 108, thereby making every beam a deflectable beam 212, wherein some of the beams 108 are voltage deflected to a position appropriate to stationary beams 210, while others are voltage deflected to a position appropriate to deflectable beams 212, as earlier described. With this design, the voltage applied to the lower electrode leads 104 can be controlled to individually address each lower electrode extension 214 to actively reconfigure the diffraction grating to the appropriate configuration (every other, every third, every fifth, etc.) for the application in which it is being used. This advanced design is a natural extension of the embodiments presented herein and allows a single reconfigurable compound diffraction grating to satisfy all possible configuration requirements.
While only certain preferred features of the invention have been illustrated and described, many modifications, changes and substitutions will occur to those skilled in the art. It is, therefore, to be understood that the subsequent associated claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. | A reconfigurable compound diffraction grating is fabricated using microelectomechanical systems (MEMS) technology. The compound grating structure can be viewed as the superposition of two separately configured gratings. A common lower electrode is placed beneath selected beam elements, known as deflectable beams, to achieve the desired grating configuration (i.e. every other, every third, every fifth, etc.) of the beams in the primary grating. These deflectable beams alone comprise a secondary, lower resolution grating structure. The beam elements are linked to a common upper electrode. Voltage applied across the electrodes creates an electrostatic force that pulls the selected beams down toward the underlying electrode. Changing the vertical position of the selected beams with respect to the other stationary beams presents a different ruling spacing distribution to the incoming radiation. By changing this distribution, the diffracted power among individual diffraction orders of the wavelengths is altered. Controlling the diffracted signal in this way allows for specific diffraction passbands to be fixed on a particular detector or a particular area of a detector. Automated adjustments to the rulings can be very rapidly, which would significantly simplify and reduce the time necessary for complete spectral analysis previously achieved by mechanical movement of diffraction gratings. | 6 |
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application is a U.S. national stage application of international application No. PCT/FI2003/000745, filed Oct. 8, 2003 , the disclosure of which is incorporated by reference herein, and claims priority on FI 20021804 filed Oct. 9, 2002, and on FI 20022161, filed Dec. 5, 2002.
STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
[0002] Not applicable.
BACKGROUND OF THE INVENTION
[0003] The present invention relates to a method for manufacturing paper and paperboard products, the method comprising the steps of monitoring web formation during the manufacturing process and surface sizing the web at least on one side. The method also allows the control of curl in the manufactured product. The invention also relates to a product manufactured by virtue of the method.
[0004] In paper manufacture, as factors of increasingly higher importance have arisen a precise adaptation of the properties of the product being manufactured to the buyer's quality requirements and optimization of energy and raw material consumption during product manufacture. Various paper grades are produced for a broad spectrum of applications, whereby the end user requirements may differ widely. Examples of such products are copier and printer paper grades. Among other qualities, the qualities of these grades should include low Tinting and sufficient stiffness to make them run smoothly via the paper feed paths of copier/printer equipment. Obviously, the surface properties of the paper must be good to secure high quality of print. These properties are attained by using a base web that has a sufficiently high basis weight, is formed from high-quality fiber and additionally is surface sized. Due to these basic requirements, the price of copier paper becomes high, because a large amount of fiber is used to obtain a high basis weight and the application of a surface size loads the web with imported surplus water that must be evaporated using a lot of energy.
[0005] The function of surface sizing is to improve the surface qualities of a product, where size also improves the internal strength of the web. In order to additionally improve the internal strength of the web by sizing, the size furnish must have a high water content to make the furnish penetrate deep into the web. As a result, a high drying capacity is needed, even further accentuated by the fact that water is the more difficult to remove the deeper the penetration of water into the web. Hence, drying of surface size makes up a substantial portion of the drying capacity that must be used.
[0006] On a papermaking machine used for producing surface-sized paper grades, sheet curl can be managed today by using a twin-felted run system on the post-dryer section or, alternatively, treating the underside of the web with water and steam on single-felted runs. In a twin-felted system, symmetrical drying can be attained by proper adjustment of steam pressures on the upper and lower cylinders. Inasmuch as heat in a single-felted system is introduced to the web via one side only and evaporation can take place principally only from the same side (bottom side), the paper or paperboard web tends to billow out toward the top side. For a two-sided paper, a simple rule to remember is that curl occurs toward the side drying last. While the same rule applies to both twin-felted and single-felted runs, the effect is less pronounced on twin-felted runs.
SUMMARY OF THE INVENTION
[0007] It is an object of the present invention to provide a method suited for making paper products at lower raw material and specific energy consumption than those required in the manufacture of conventional products having similar qualities.
[0008] It is a further object of the invention to provide an embodiment of the invention suited for the control of curl of a paper or paperboard product being manufactured.
[0009] The goal of the invention is achieved by way of keeping the speed differential, or the draw, between the press section and the dryer section of the paper/paperboard making machine lower than 3% and performing surface sizing with a size furnish wherein the proportion of size solids is at least 15%.
[0010] The invention offers significant benefits.
[0011] By virtue of keeping the draw between the press section and the dryer cylinders lower than 3%, the internal bond strength (Hyugen), work-to-rupture and breaking elongation increase while web porosity decreases. As a result, surface sizing need not be used for increasing the internal bond strength of the product, but rather, size furnishes of higher solids can be used, whereby the size remains on the web surface. Thus a web structure is attained having the size layers coating the product surfaces and the base sheet acting as a middle layer in the same fashion as in a composite structure. The outcome is a very stiff product in regard to its basis weight. Such a product is well suited for use as a copier paper or, if manufactured as a paperboard grade, as a packaging cardboard. By way of keeping the s small, the tensile strength of the web remains substantially equal in both the cross-machine and machine directions. In the perpendicular direction (z-direction) to the paper surface, the breaking elongation and the work-to-rupture increase.
[0012] On the other hand, reduction of the sheet basis weight increases the internal bond strength by 10-20% thus allowing a higher size solids to be used in conjunction with a lower basis weight. In a surface sized paper, there is a crosscorrelation between the sheet basis weight and the draw in the press section such that setting the draw at 1 to 2% gives in the reduction of basis weight a more pronounced effect on the increase of internal bond strength than a draw of about 3%. Hence, the reduced basis weight made possible by using a lower draw on the press section enhances the other benefit obtained by the lower draw.
[0013] The above discussed variables related to the strength of the base sheet, particularly the lower porosity, principally result from the fact that the reduced draw causes less debonding of the fibers in the base sheet and reduces the deformation of fibers because the tensile stress of the web is reduced at the reduced draw. Thus, the lower draw cannot cause damage to the web by tensile elongation.
[0014] However, the benefits of reduced draw can be attained only through the use of modern web speed control methods. Obviously, as the function of draw is to keep the web tight on the rolls of the papermaking machine, it has been necessary at high web speeds and in the handling of wet web to keep the web under high tensile stress, that is, under tight draw. Among other variables, the lower draw is facilitated by improved web guidance with the help of wires and felts in combination with high-vacuum suction boxes that remove the web from the surface of the rolls.
[0015] When the draw is reduced, the machine-direction Young's modulus is lowered slightly while the cross-machine Young's modulus stays unchanged, the latter being vital particularly in the manufacture of copier paper inasmuch as the flexural stiffness especially in the cross-sheet direction is crucial to secure consistently reliable sheet infeed in the copier/printer.
[0016] By way of increasing the solids content of the surface size, the amount of water imported to the web is reduced with the immediate result that less drying capacity is needed in the process. This benefit is further accentuated by the lesser absorption of water into the web. The surface size furnish may be complemented with other additives such as brightener or pigment particles. Particularly the use of a brightener has been found advantageous. As the surface size remains on the surface of the web, the consumption of possible additives is small because no loss of additives via absorption into the base sheet takes place. Hence, more liberal use of expensive additives may be considered, too. One specific feature of brightener addition is that the method according to the invention increases the whiteness of the product, which is in contrast to the traditional belief in the art that the use of a brightener is detrimental to product whiteness. By having a distinct, sealing layer of surface size formed on the sheet surface, the product according to the invention is well suited for use in ink-jet printing and similar hardcopy processes, because the ink cannot excessively penetrate into the fibers and interfiber voids, whereby the contours of ink spots and printed patterns become sharply defined.
[0017] Control of web curl can be managed by virtue of the method according to the invention either via changing the amount of surface size application or the water content of the surface size furnish. As the starch of the surface size at high size solids forms a layer on the base paper surface, the sized sheet acts like a layered composite structure in which the surface sized top/bottom layers serve as the shell element. This shell element gives a vital contribution to the flexural stiffness of the sheet and, thereby, to the web curl. Hence, the method according to the invention offers efficient tools to the control of web curl. In summary, the following benefits are gained:
existing dryer sections can be run at higher web speeds, control of curl in the web requires no water and steam, or at least a marginal amount in regard to current practice will be sufficient, and runnability and production efficiency can be retained at a high level.
[0021] Moreover, control of curl can be still further essentially improved over the prior art by virtue of using different size furnishes on the two sides of the web, whereby for instance the solids of the two sides can be adjusted differently from each other. The effect on absorption, however, is such that absorption on the bottom side of the web increases inasmuch as a larger amount of water is applied thereon by virtue of the web curl control system.
[0022] While the paper and paperboard qualities manufactured using the method according to the invention are not generally calendered or coated, there is no hindrance to forwarding the manufactured product to such further finishing steps.
[0023] In the following, the invention is examined with the help of an exemplary embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Not applicable.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] The paper grade of the example is well suited for use as copier or printer paper.
[0026] Today, copier equipment manufacturers recommend the use of a copier paper grade having a basis weight of 80 g/m 2 . This recommendation aims to secure a sufficient sheet stiffness in the infeed and printing sections of copier/printer equipment. Typically, this kind of paper is surface sized using a furnish having a solids content of about 10% and applied, e.g., 10 g/m 2 as a wet film on both sides of the web. Then, the portion of dry weight of size solids is 2 g/m 2 , whereby the basis weight of the base sheet must be 78 g/m 2 .
[0027] According to the invention, the internal bond strength is secured by keeping the draw between the press section and dryer section of the papermaking machine lower than 3%, advantageously in the range 1-2%, whereby the internal bond strength required from the base sheet stays good. If the basis weight of the base sheet is lowered to a value of 68-72 g/m 2 , the computational value of product stiffness reduction is 15-25%. This stiffness reduction due to thinner base sheet is compensated for by using in surface sizing a furnish of 25% solids in the dry weight of the size, whereby the product has a sufficient stiffness and at least equal surface qualities as those of a comparative product surface sized with a smaller amount of size. In this context, the dry solids of the size is defined as the proportion of the actual solids of the size in regard to the amount of water in the furnish. While the overall solids of the furnish may be increased substantially for instance when using pigment additives, at the lower end of solids content the proportion of size components in the total amount of size material and water should not be less than 15% to avoid excessive penetration of size furnish into the interfiber voids. Advantageously, the size solids is at least 20%, most advantageously 25%. As a dry weight of the size layer, the total amount of applied size may be equal to the layer weight when size is applied using a furnish of less solids, but in the case that the product basis weight is precisely specified, e.g. at the above-mentioned 80 g/m 2 , the amount of size may be increased. Making the product from a base sheet of 68 g/m 2 basis weight, for instance, the application of a 25% solids size requires the size furnish to be applied by 24 g/m 2 of the wet size film on both sides of the base sheet which is a rather large amount of applied size that may preferably be implemented using even a greater amount of size solids.
[0028] The invention makes it possible to optimize the consumption of raw materials and, particularly, the product stiffness. As the size remains on the product surface, the contribution of the size layer to the product stiffness is substantial, whereby the product stiffness can be modified more easily by changing the applied size weight than by using a base sheet of different basis weight. Because the surface size is not necessary to increase the internal bond strength of the base sheet, the properties of the size can be fully utilized to improve the surface qualities and stiffness of the paper product.
[0029] While the invention is particularly suited for manufacturing copier and ink-jet printer paper grades, it may also be utilized in other kinds of products specified for a good ratio of stiffness to basis weight, even in packaging cardboard grades. Furthermore, in principle it is possible to surface size the web only on one side if such a product is requested. Obviously, the surface size furnish may be prepared based on some other liquid than water, whereby the proportions of size components must be computed relative to the total volume of liquid.
[0030] In the product according to the invention, the goal is to keep the size in the coat layer of the product and the penetration into the interfiber voids must be minimal. To this end, at least 80%, advantageously 90%, of the total amount of applied size shall remain on the base sheet fiber layer.
[0031] The increase of solids in the surface size furnish allows the top and bottom sides of the web to be coated with the same amount of size but in different amounts solids, whereby the amounts of water applied to the two sides of the web may be varied widely. The size solids can be varied in a range as wide as 8 to 30%. If the solids of the dried size is adjusted to 1.5 g/m 2 , it means that the amount of water applied to the web is 3.5 g/m 2 minimum and 17.3 g/m 2 maximum. Obviously, the range of allowable water application is really wide. Inasmuch as this difference in the amount of water applied to the two sides of the web makes it possible to efficiently control the tendency of the web to curl after drying, whereby the curl of the paper web is maximally easy to manage.
[0032] Typically, on a prior-art surface-sizing press, there is applied to the web an aqueous furnish of surface size containing water in such an amount that the solids content of a web of 70 g/m 2 basis weight falls from 97% to about 70%, whereby the web contains 30 g/m 2 water distributed essentially uniformly over the cross-machine direction of the web. Removal of this excess moisture content from the web requires plural dryer cylinders. If the dryer construction is based on single-felted runs, a moisture content gradient is formed when the bottom side dries first, whereby the web is subjected to internal stresses that force the web to billow out toward its top surface.
[0033] In a situation where the amount of water imported to the web is only half of that applied conventionally, a feasible arrangement could be such that, for instance: size furnish is applied on both the top surface and the bottom surface by the same amount of 1.5 g/m 2 furnish having different solids contents so that the dry solids of the bottom side furnish is 10% while 25% dry solids is applied to the top side. The corresponding amounts of imported water are 13.5 g/m 2 and 3.5 g/m 2 . Resultingly, the moisture content to be removed from the bottom side is more than three times greater than the moisture content evaporating from the web top side. Hence, a radical change takes place in the distribution of evaporation in a single-felted dryer group. Due to the substantially smaller amount of moisture being evaporated via the top surface, the web curl may be expected to be reduced and even change its billowing direction if the difference between the amounts of water applied to the top and bottom sides of the web is adjusted to a sufficiently large degree.
[0034] Using the above-mentioned amounts of surplus water (13.5 g/m 2 and 3.5 g/m 2 ) imported to the web of 70 g/m 2 basis weight discussed in the exemplary embodiment above, the solids content of the web will be 80.5% which is substantially more than the 70% conventionally used in the art. Also, the number of required dryer cylinders is reduced. For instance, on a papermaking machine having 12 cylinders in a single-felted run, the drying process is as follows: the two last cylinders of the dryer group are cooling cylinders and a surplus amount 1 g/m 2 water is imported to the web at the end of the dryer section. Now, with the provision that the amount of water imported to the web during sizing can be lowered in the fashion described in the exemplary embodiment, the reduction in the amount of imported water is about 43% in regard to the conventional level (30 g/m 2 vs. 17 g/m 2 ). Hence, the number of dryer cylinders can be reduced by about 40% as compared with the prior art. | A web of paper or paperboard is manufactured by first forming a base web that is dried on the press section of papermaking machine. The base web is further dried on the dryer section of the papermaking machine and a base web speed differential, or draw, is set between the press section and the first dryer cylinder group of the dryer section, whereupon at least one surface of the web is surface sized. The draw is set to 3% maximum, and a surface size furnish is applied having a solids content of at least 15% of the total amount of size components and liquid in the furnish. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to electrically erasable, programmable, read only memory (EEPROM) devices and, in particular, to a flash EEPROM memory system suitable for low voltage operation and a method of controlling such memory.
2. Background Art
Programmable, electrically erasable, read only memories are non-volatile field effect devices which utilize a floating gate structure. Standard EEPROMs, or electrically erasable, programmable memories, include memories wherein the cells may be individually programmed and erased. However, this type of EEPROM requires a wide range of voltages for programming, reading and erasing and the cells are relatively large.
Flash EEPROMs have been developed which have a smaller cell size then standard EEPROM. Flash EEPROMs have cells that cannot be individually erased, but are erased either in bulk or by sector. Referring now to the drawings, FIG. 1A depicts a conventional N channel flash EEPROM memory cell 18, commonly referred to as the Intel ETOX cell or simply the ETOX cell. The cell includes a graded N type source region 20 diffused into a P type substrate 22. An N type drain region 24 is also diffused into the substrate 22 so as to define a channel region 22a between the source and drain regions. The source region 20 is formed more deeply into the substrate 22 than is the drain region 24.
A polysilicon floating gate 26 is disposed above the channel 22a and is separated from the channel by a thin (about 100 Å) gate oxide 28. A portion of floating gate 26 extends over the graded source region 20. A polysilicon control gate 30 is disposed above the floating gate 26 and is separated from the floating gate by an interpoly dielectric layer 32.
FIGS. 1A-1C show typical conditions for programming, reading and erasing the cell 18, assuming that the primary supply voltage Vcc is +5 volts.
As shown in FIG. 1A, the ETOX flash cell is programmed by applying a programming voltage +Vpp (typically +6 to +8 volts) to the drain region 24 and a higher voltage Vgg (typically +10 to +13 volts) to the control electrode. The source region is grounded (Vss). Voltage +Vpp is usually supplied from an external source and voltage Vgg is usually provided by way of a charge pump type circuit. Alternatively, both Vpp and Vgg can be provided by a charge pump circuit, with only primary voltage Vcc being provided by an external source or supply.
The ETOX cell is programmed in the conventional standard EEPROM manner. Electrons exit the source 20 and are accelerated across the channel 22a towards the drain region 24. As the electrons approach the drain, the positive charge on the control gate 32 results in avalanche or hot electron injection near the drain 24 through the gate oxide and into the polysilicon floating gate 26. As will be explained, the presence of electrons on the floating gate 26 of a programmed cell produces characteristics which differ from an unprogrammed cell.
The conventional ETOX cell is read in the manner shown in FIG. 1B. The source region 20 is grounded (Vss) and an intermediate voltage +Vf (typically +1 to +1.5 volts) is applied to the drain region 24. Voltage +Vcc is applied to the control gate 30. In the case where the cell had been previously programmed, the negative charge present on the floating gate will tend to prevent the positive voltage on the control electrode 32 from inverting the channel. Thus, the negative charge on the gate effectively increases the threshold voltage of the cell so that the cell will not be rendered conductive by the voltage +Vcc applied to the control gate 30. Accordingly, no current flow will take place through the cell other than some amount of leakage current.
In the event the cell of FIG. 1B was not previously programmed, the threshold voltage of the cell will be sufficiently low such that the cell will be rendered conductive by voltage +Vcc. This will result in current flow through the cell which will be detected by the sense amplifier.
The ETOX cell is erased in the manner depicted in FIG. 1C. The drain region 24 is left open (floating) and control gate 30 is grounded (Vss).
Positive voltage +Vee, typically ranging from +11 to +13 volts, is applied to the source region 20 which results in electrons being drawn off floating gate 26 through the thin gate oxide 28 to the graded source region 20. This occurs in the region of the graded source which underlies the floating gate 26. The mechanism for such removal of electrons is known as Fowler-Nordheim tunneling. The graded source 20 provides a smooth curvature which increases the gate-aided junction break down voltage. Thus, the asymmetrical drain/source configuration, including the graded source and the section of the source underlying the floating gate 26 enhances the Fowler-Nordheim tunneling mechanism used in the erase process.
FIG. 2 shows a conventional memory array 32 comprised of flash cells 18 arranged in rows and columns. The source regions 20 of each of the cells is connected to a common source line S. Note that cells located in a particular column are arranged in pairs, such as the pair comprising cells 18A and 18B, with each cell 18 of a pair having a reversed orientation so that the source regions are adjacent to one another. The drain region 24 of each cell 18 located in a particular column is connected to a common bit line BLN. Further, the control electrode 30 of each cell located in a particular row is connected to a common word line WLN.
The memory system includes the memory array 32 and associated circuitry (not depicted) for decoding read/write addresses and for applying the appropriate voltages necessary for carrying out the program, read and erase steps. In addition, the associated circuitry includes sense amplifiers and related components for reading the array.
Operation of the conventional memory system is best described by way of example. If cell 18A is to be programmed, positive voltage +Vgg is applied to the selected word line WL1. The deselected word lines WL0, WL2, WL3 and WLN are all grounded. In addition, positive voltage +Vpp is applied to the selected bit line BL2, with the deselected bit lines all being grounded (Vss). Cell 18A will be programmed as previously described in connection with FIG. 1A. The deselected cells in the same column, such as cell 18B, will not be programmed because of the deselected word lines, including line WL0, are grounded. Similarly, the deselected cells in the same row, such as cell 18C, will not be programmed because the deselected bit lines, including line BL1, are grounded (Vss).
Reading is carried out by applying voltage +Vcc to the selected word line, such as line WL1 if cell 18A is to be read. The deselected word lines, WL0, WL2, WL3 and WLN, are all grounded as is the common source line S. Further, the deselected bit lines BL0, BL1 and BAN are all grounded (Vss) and the selected bit line BL1 will be connected to positive voltage +Vf. The deselected cells will not be rendered conductive. For cells in the same column, such as cell 18B, the grounded word line WL0 will maintain the cell in a non-conductive condition. For deselected cells in the same row, such as cell 18C, such cells will remain non-conductive since the associated bit lines are grounded (Vss).
Although not depicted, the memory system includes a sense amplifier and load associated with each column for sensing current flow through any of the cells located in the column. The load, which is typically an MOS transistor, is connected between the bit line and voltage +Vcc and functions as a voltage divider so as to produce voltage +Vf when no current is flowing through the bit line. In the event the selected cell 18A is in the unprogrammed or erased state, the cell will conduct current so that current flow will take place between bit line BL1 and the common source line S. The current will flow through the associated load will cause the voltage on the bit line to drop from the quiescent value of +Vf to a lower value. In the event the cell has been programmed, the cell will remain non-conductive and the voltage on the bit line will remain unchanged except for the changes attributable to leakage current. The output of the sense amplifier will thus reflect the programmed state of the selected cell.
The erase sequence is carried out by connecting the common source line S to positive voltage +Vee, grounding (Vss) all of the word lines WLN and floating all of the bit lines BAN. This causes all of the cells 18 of the array to be erased.
There has been a tendency to reduce the magnitude of the supply voltage so as to permit battery operation. By way of example, voltage +Vcc can be reduced from a typical value of +5 volts to +3 volts. The other voltages, including voltages +Vp and +Vgg, are then typically generated using on-chip charge pump circuitry.
One disadvantage of low voltage operation is that a low value of +Vcc results in a low cell current during a read operation (FIG. 1B). A low cell current results in slow access times since the amount of current available to charge and discharge the memory line capacitances is small. In order to increase the cell current, it would be possible to utilize an on-chip charge pump to generate a larger voltage +Vcc, but charge pumps increase the die size and waste power. Further, since the voltage +Vcc applied to the control electrode must be rapidly switched on and off during successive read operations, the inherent slow speed of charge pumps greatly reduces the time required to read the memory. Since memory read operations are much more critical to overall speed of the memory as compared to program and erase operations, this is highly undesirable.
One approach to increasing cell current is to decrease the threshold voltage of the cell. However, this will result in large leakage currents in deselected cells despite the fact that a low voltage is applied to the control gate of such cells. In addition, there is a tendency to program cells having a low threshold voltage when such cells are read. This phenomena, known as program disturb, is not desirable.
The present invention overcomes the above-noted shortcomings of conventional memory systems. Low voltage operation is achieved without the use of charge pumps to supply voltage +Vcc. Further, cell current is sufficient so as to maintain high speed memory read operations while maintaining immunity to leakage current from deselected cells and while avoiding program disturb. These and other advantages of the present invention will be apparent to those skilled in the art upon a reading of the following Detailed Description of the Invention together with the drawings.
SUMMARY OF THE INVENTION
A flash memory system is disclosed which includes an array of flash memory cells and control means for controlling operation of the system. The cells each include a source region, a drain region, a channel region intermediate the source and drain regions, a floating gate disposed over and insulated from the channel region and a control gate disposed over and insulated from the floating gate. The cell is preferably an N channel device and is fabricated to have a relatively low threshold voltage so that the system is operable at low supply voltages.
The cells located in one of the array columns have their drain regions connected to a common bit line and the cells located in a row have their control gates connected to a common word line. All of the cells of the array have their sources connected to a common source line.
The memory system further includes control means for controlling the operation of the system. The control means includes erase means for erasing the memory cells, program means for programming the memory cells and read means for reading the memory cells. The program means includes means for applying a positive voltage with respect to the memory array circuit common to the bit line associated with the cell to be programmed. Preferably, the source line is grounded so that current flow through the cell being programmed is from the drain connected to the bit line to the grounded source.
The read means of the control means includes means for applying a positive voltage with respect to the array circuit common to the common source line. The bit line associated with the cell being read is at a lower voltage so that current flow will be in the opposite direction as occurs when the cell is programmed. The cell can then be read at the source line. As will be explained, this arrangement greatly reduces leakage current despite the low cell threshold voltage.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1C depict a conventional flash EEPROM cell and the manner in which the cell is programmed, read and erased, respectively.
FIG. 2 is a conventional array of flash memory cells arranged in rows and columns.
FIG. 3 is a memory system in accordance with the present invention.
FIG. 4 is a block diagram of the sense amplifier and associated circuitry used in reading cells of the subject memory system.
DETAILED DESCRIPTION OF THE INVENTION
Referring again to the drawings, FIG. 3 is a block diagram of the memory system in accordance with the present invention. The system utilizes a conventional array 32 of flash memory cells 18 as depicted in FIG. 2. The cells 18 are similar to those depicted in FIG. 1 and have an asymmetrical drain/source configuration. For purposes of definition, for the N channel devices of FIG. 1, the drain is the region connected to the most positive voltage during a programming sequence. In the event a P channel device is used, the source is the region connected to the most positive voltage during a programming sequence.
The flash memory cells 18 of array 32 have been fabricated to have a low erased threshold voltage Vterase of approximately +0.5±1 volts and a programmed threshold voltage Vtwrite of approximately +4 to +5 volts. The system further includes a Control Circuit 34 for controlling the overall operation of the memory system. Circuit 34 functions to decode addresses to be used for memory reads and memory writes and receives data to be written in the memory. This information is used to control a Row Decoder 36 and a Column Decoder 38 so that certain predetermined voltages are applied to the word lines WLN, bit lines BLN and the source line S to carry out the read, program and erase operations.
Table 1 below shows exemplary voltages to be applied to the array 32 for carrying out these operations. These voltages are suitable for operating the memory system from a +3 volt battery supply. Voltage +Vcc is the +3 volt battery voltage, with the remaining voltages preferably being produced by on-chip positive and negative charge pumps. Of course, these nominal voltages may have to be adjusted depending upon the actual process dependent characteristics of the flash cells 18.
TABLE 1______________________________________ READ PROGRAM ERASE______________________________________SELECTED +Vcc +Vgg -VeeWORD LINE (+3 volts) (≦+10 (-13 to volts) -16 volts)DESELECTED Vss -Vc -VeeWORD LINE (ground) (-2 volts) (-13 to -16 volts)SELECTED +Vf +Vpp Vss or FBIT LINE (+0.5 to (+5 to (ground or +1 volts) +6 volts) floating)DESELECTED +Vcc Vss Vss or FBIT LINE (+3 volts) (ground) (ground or floating)SOURCE LINE +Vcc Vss +Vcc (+3 volts) (ground) (+3 volts)______________________________________
As set forth in Table 1, a selected cell 18A (FIG. 2) is programmed by causing Row Decoder 36 to apply voltage +Vgg of +10 volts or less to the selected word line, this being line WL1 for selected cell 18A. This value compares to +12 to +13 volts usually used for programming cells having the more typical lower programmed threshold voltages Vtwrite of +4 to +5 volts. The Control Circuit 34 also causes Row Decoder 36 to apply voltage -Vc of -2 volts to the deselected word lines WL0, WL2, WL3 and WLN. Again, this value compares to the typical approach of grounding the deselected word lines for cells having a higher Vterase threshold voltage.
As can be seen in Table 1, the program sequence is further carried out by the Control Circuit 34 causing the Column Decoder 38 to apply voltage +Vpp of +6 volts to the selected bit line BL2 and to ground (Vss) the deselected bit lines BL0, BL1 and BLN. In addition, Column Decoder 38 is caused to ground (Vss) the common source line S.
With the above-described conditions, cell 18A will be programmed by way of hot electron injection from the grounded source region. The deselected cells in the same column as cell 18A, such as cell 18B, will not be programmed due to the negative voltage -Vc being applied to the control gate by way of the associated word line WL0. The deselected cells in the same row but different column, such as cell 18C, will not be programmed due to the grounding of the associated deselected bit line BL1. The other deselected cells of the array will not be programmed due to the combination of grounded deselected bit line and the negative voltage -Vc applied to the deselected word line. Such negative voltage further functions to reduce the leakage current of other cells located in the same column as the target cell 18A.
As can also be seen in Table 1, the entire array is erased when the Control Circuit 34 causes the Row and Column decoders to apply -Vee ranging from -13 to -16 volts to all of the word lines and to either ground (Vss) all of the bit lines or leave all of the bit lines floating. In addition, the Column Decoder 36 is directed to apply voltage +Vcc of +3 volts to the common source line S. Under these conditions, all of the cells 18 of the array will be erased by way of Fowler-Nordheim tunneling.
In some applications, it may be desirable to erase less than the entire array. In that event, the array is divided into segments, with each segment having a common source line S. Such array segments are considered to be an array in itself, as that term is used here. Similarly, the array can be configured so that more than a single cell, such as a byte, can be programmed in a single operation and can be read in a single operation. Such arrays are typically implemented by operating array segments in parallel. In that event, the portion of the array containing a single cell of the group, an array segment, is considered to be an array in itself, as that term is used here.
Table 1 also shows the voltages applied by the Column Decoder 38 and Row Decoder 36 for reading a selected cell 18A of the array 32. The Row Decoder is caused to apply +Vcc of +3 volts to the selected word line WL1 and to ground (Vss) the remaining deselected word lines WL0, WL2, WL3 and WLN. The Column Decoder 38 is caused to apply voltage +Vf to the selected bit line BL2 and to apply voltage +Vcc of +3 volts to the deselected bit lines BL0, BL2 and BLN. Further, the common source line S is also connected to voltage +Vcc of +3 volts by the Column Decoder 38. The Row Decoder is caused to apply voltage +Vcc of +3 volts to the selected word line WL1 and to ground (Vss) the deselected word lines WL0, WL2, WL3 and WLN.
Under the above-described conditions, assuming that selected cell 18A has not been programmed, the cell will conduct current. It is important to note that the direction of current flow will be the opposite to the direction of flow when the cell is programmed. The direction of current will be from the common source line S, which is at +3 volts (+Vcc), to the bit line BL1 which is at a voltage less than +3 volts. Thus, current flow is from the source of the cell to the drain, with the source and drain being defined by the direction of current flow when the cell is programmed.
In conventional flash memory systems, the direction of current flow is from the bit line, through the cell and to the grounded source. In the present memory system, the direction of current flow is in the opposite direction so that specially adapted current sense circuitry is required to carry out a read operation. FIG. 4 shows such special current sense circuitry located in the Column Decoder 38. There is one group of such current sense circuitry associated with each bit of the word length, with the word length being dependent upon the particular memory architecture being used. By way of example, if the architecture is for an eight bit word, there will be a total of eight sense circuits, with the sense circuits being connected by way of decoder transistors (not depicted) to the appropriate column in which the cells 18 are located.
Cell 18A of FIG. 4 represents the selected memory cell. The source of the cell 18 is connected to the common source line S which is connected to voltage +Vcc. The drain of the selected cell 18 is connected to one of the bit lines BLN. The other deselected cells located in the same column are also connected to the same bit line, but are not shown. A P channel MOS transistor 40 is connected between ground and the bit line BLN and acts as a load for the cell 18A during read operations.
A circuit comprising another P channel MOS transistor 42 and an N channel transistor 44 function to amplify and invert the voltage present on the bit line BLN, with such voltage being indicative of the programmed state of the cell 18A. A separate bias voltage is applied to the gate of MOS transistor 44. The output of the read amplifier at the junction of transistors 42 and 44 is connected to a Sense Line. The Sense line is connected back to the gate of MOS transistor 40 to provide positive feedback. Such regeneration functions to increase the gain of the sense circuitry. The Sense line will be at a high voltage if the cell 18A being read is in a programmed state and a low voltage if the cell is in an erased state.
The subject memory system further includes reference circuitry including a reference cell 46 connected to the same voltages as is the cell 18 being read. Reference cell 46 is located in a column of reference cells, with each reference cell being located in a row associated with word lines WL0-WLN. Reference cell 46 is located in the same row as the cell being read and is connected to the same word line WL1. Not shown are the other deselected reference cells located in the reference column in the deselected rows.
A P channel MOS device 48 functions as a load for the reference cell 46. The reference output on line 47 is amplified by an inverting amplifier which includes P channel MOS device 50 and N channel MOS device 52 which are configured in the same manner as MOS devices 42 and 44. The output of the reference circuit inverting amplifier is on the Reference Line.
Reference load MOS transistor 48 has a geometry which is larger than that load MOS transistor 40 so that the voltage drop across transistor 40 is greater than that across transistor 48 for the same amount of cell current. Reference cell 46 is unprogrammed so that it will conduct approximately the same amount of current as the cell 18A being read, assuming that cell 18A is also in an erased state. The leakage current in the deselected cells 18A connected to the same bit line (same column) as the cell 18A being read will tend to be offset by the leakage current of the deselected reference cells (not depicted) also connected to line 47.
The geometries of load MOS devices 40 and 48 are selected so that the voltage on the Reference Line fall midway between the voltage on the Sense Line when the cell 18A being read is in a programmed state and the voltage when the cell being read is in an erased state. A conventional sense amplifier 54 compares the level of the signal on the Sense Line with the level on the Reference Line and produces a corresponding digital output on the Data Output line.
The disclosed memory system is ideal in that the cell 18 current during read operations is large (assuming it is in an erased state) notwithstanding the use of a low value supply voltage +Vcc of +3 volts. The cells are fabricated to have low threshold voltages to provide the high read current yet leakage normally attributable to low threshold voltage cells is minimized. Although the deselected word lines in the read operation are at ground potential (Vss), this would be sufficient in some circumstances to turn on a low threshold voltage cell, should the cell source also be grounded. However, in the present case, the cell source is not grounded, but rather the sources of each of the cells of the array is placed at voltage +Vcc. This functions to reduce the cell leakage current.
The conductivity of the subject memory cells is directly related to the voltage between the control gate and the voltage of the drain region connected to the bit line BLN. A positive voltage equal to the drop across load MOS device 40 will be present on the bit line. From a device physics point of view, the region of cell 18A connected to the bit line BL2 functions as the source but for the sake of consistency in terminology, the regions are defined by their function in program operations. In program operations, the flow of cell current is in the opposite direction, so that the region connected to the bit line functions as the drain. Thus, the gate-drain voltage of the cell during read operations is the primary voltage controlling the conductivity of the cell. The voltage on the bit line BL2 has a polarity which will tend to reduce the gate-drain voltage of the deselected cells located in the same column in which the selected cell is located. Thus, assuming that the selected cell is cell 18A (FIG. 2), the leakage current from these deselected cells, such as cell 18B, will be lower than in the case where the source is connected to ground.
With respect to the deselected cells located in other columns, such as cell 18C, both the drains and sources of these cells are connected to +Vcc. The polarity of the gate-drain voltage is thus in a direction which tends to turn the cell off. Further, since both the drain and source are at the same voltage, there will be insignificant leakage flow through these deselected cells.
It should also be noted that there will be a reduced tendency for a cell 18A being read to be programmed disturbed, despite the low threshold voltage. When cell 18A is read, the source region rather than the drain region is at the positive voltage. Thus, any undesired program current for producing hot electron injection will have to originate from the drain region 24 (FIG. 1A) of the cell rather than the source region. However, since the cells have an asymmetric drain/source configuration, with the cell optimized for the generation of programming currents at the source rather than the drain, there will be a substantially reduced tendency for program disturb to occur.
The subject memory system can be fabricated using conventional integrated circuit processing steps. Such steps form no part of the subject invention and will not be disclosed so as not to obscure the true nature of the invention in unnecessary detail.
Thus, a novel flash memory system has been disclosed capable of operating efficiently at low supply voltages. Although a preferred embodiment of the system has been described in some detail, it is to be understood that changes can be made by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims. | A flash memory system utilizing low threshold voltage cells so as to provide adequate cell current during read operations even with at low power supply voltages. The cells are arranged into an array of rows and columns, with the source regions of all of the cells connected to a common source line, the drain regions of the cells in one of the columns connected to a common bit line and the control gates of the cells in one of the rows connected to a common word line. In program operations, voltages are applied to the cells so that the program current flows from the cell bit line to the common source line. This results in electrons being injected from the drain toward the floating gate and the floating gate thereby altering the threshold voltage of the cell. In read operation, voltages are applied so that current flow is in the opposite direction, namely from the source line to the bit line. The read current is then sensed at the source line by way of a sense amplifier and associated circuitry. This arrangement minimizes undesirable leakage currents during read operations notwithstanding the use of low threshold voltage memory cells. | 6 |
PRIORITY CLAIM
Priority is claimed to U.S. provisional patent Ser. No. 61/296,620, filed Jan. 20, 2010, which is incorporated herein in its entirety by reference.
BACKGROUND OF THE INVENTION
In construction, deck units are used to construct a deck system. A deck unit is comprised of one or more profiled forms made of steel that is handled as a single building component. Deck systems are simply a group of deck units that are fastened together in sufficient number to make the deck system of desired size.
The deck unit or deck system may support a layer of structural concrete in order to be used as a roof or floor, or a layer of lightweight insulating concrete in order to be used as a roof or may be used without the concrete.
Deck units include hat-shaped, profiled panels which are fastened to an exposed bottom panel to form closed cells within the deck units. The interiors of these cells may be used as air ducts, for running conduit for utilities and cabling, and to carry sound-absorbing materials.
Large open spaces, such as airport terminal areas and stadiums often have ceilings made of closed cellular deck systems. Often, these deck systems will also support hanging fixtures such as lighting, signs and sprinkler pipes.
There is a continual need for stronger deck systems that can span greater distances and have more capabilities while still possessing aesthetic qualities for public places.
SUMMARY OF THE INVENTION
The present invention is a deck unit comprising one or more top hat portions of various sizes and shapes joined to an exposed dove-tail bottom panel. The bottom panel includes at least one or more dovetail-shaped recess. A deck system is made by joining the present deck units.
Each deck unit includes a central hat-shaped panel with integral first and opposing second side laps of an attached bottom panel. The bottom panel is dimensioned to span the underside of one or more hat-shaped portions, and to have hidden side laps that nest with side laps of the hat-shaped portion. The deck units are fastened together to form the deck system. Importantly, the bottom panel has at least one “dove-tail”-shaped recess formed in it. These recesses, which may be concave upward or downward, provide additional strength to the deck unit and deck system, as well as a defined, confined recess in the bottom panel for use in concealing and running conduit and also in providing vertical support for lighting and other hanging type vertical loads when the present deck system is used as a roof/ceiling or floor/ceiling.
A feature of the present invention is the dove-tail shaped recesses formed in the bottom panel and throughout its length. The configuration of these dove-tailed panels and hat-shaped deck profiles together substantially increase stiffness to the deck system while providing the clean, plank-like appearance of the exposed underside of the deck system. Furthermore, the dove-tailed recesses provide additional capabilities to the deck system. Because the recess may be only partially closed, that is, it may have a narrow gap when viewed from below, it allows the deck system to support and conceal connections for exterior ceiling lighting and signage and aids in attenuating sound energy.
An advantage of the present system is that, from below, it has the appearance of planks, which especially in a large ceiling is aesthetically pleasing, while nonetheless providing functional spaces for acoustical materials and structural strength for the ceiling load over such long spans.
These and other features and their advantages will be readily apparent to those skilled in the art of metal deck system fabrication and construction from a careful reading of the Detailed Description of Preferred Embodiments, accompanied by the following drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the figures,
FIG. 1 is a top perspective view of a deck unit comprising two individual top hat profiles joined to a single exposed bottom panel, according to an embodiment of the present invention;
FIG. 2A is a bottom perspective view of a deck unit including two individual top hat profiles joined to a bottom panel with concave upward and open dove-tail recesses, according to an embodiment of the present invention;
FIG. 2B is a bottom perspective view of a deck unit including two individual top hat profiles joined to a bottom panel with concave downward and closed recesses, according to an alternative embodiment of the present invention;
FIG. 3 is a side view of a portion of deck system serving as a ceiling, with concrete placed above, in an embodiment of the present invention; and
FIG. 4 is a perspective, partially-cut-away view of the deck unit of FIG. 1 with deck struts inside the first and second top hat profiles, according to an embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention is a deck unit including at least one top-hat profile attached to a bottom panel for use in making a deck unit for a roof or floor. The bottom panel includes at least one dovetail-shaped recess. Adding the top hat profile to the bottom panel with dovetail recesses substantially increases the strength of the deck unit. The present deck unit can be joined together to form a deck system, which can be used with or without a layer of concrete depending on specifications for the application of use. A deck unit with more than one top hat profile attached to one bottom panel makes assembling the deck system faster, and the present description of embodiments of the present invention and accompanying drawings will show plural top hat profiles in each deck unit. However, the present deck unit may alternatively have just one or more than two top hat profiles.
Referring now to the figures, there is shown in FIGS. 1 , 2 A and 2 B, top and bottom perspective views, respectively, of a deck unit 8 . Each deck unit 8 includes two top hat profiles 10 attached to one bottom panel 12 and has a distance end to end that runs the length of a specified span of a ceiling or roof. Deck unit 8 is handled as a single unit and combined with other deck units 8 to construct a deck system of the specified width.
Although deck unit 8 is shown as having two individual top hat-shaped profiles 10 , it may be made with one top hat profile 16 . Top hat profiles 16 are integrally joined and both may be formed from a single profiled sheet of metal, preferably steel.
Each top hat profile 16 includes a top flange 22 integrally formed with two side walls 24 , 26 . Side walls 24 , 26 , may be nearly at right angles to top flange 22 , but may be canted slightly outwardly from top to bottom as shown in the figures so as to be spaced slightly farther apart at the bottom of top hat profiles 16 and slightly closer together at top flange 22 .
Top flange 22 may have one or more grooves 30 formed therein, trapezoidal in shape with the bottom 32 of groove 30 being smaller than the opening at the top of the groove 30 , and side walls 36 , 38 of groove 30 may be symmetrically flared outwardly in the upward direction. A groove 30 adds stiffening to top hat profile 16
Each top hat profile 16 has bottom flanges 42 , 44 , and each of them may have a bead 46 , 48 , formed therein to add stiffening. Deck unit 8 is formed by securing top hat profiles 10 on bottom panel 12 . Each bottom flange 42 , 44 of each top hat profile 16 of deck unit 8 is connected integrally to bottom panel 12 by a mechanical fastening process, such as by welding for example.
Bottom panel 12 is also preferably a profiled sheet of metal, such as steel, that covers the bottom openings of top hat profiles 10 of a deck unit 8 to define spaces or cells 50 therebetween. Bottom panel 12 also provides side laps 52 , 54 , for fastening adjacent deck units 8 together. Side laps 52 , 54 are formed so that a side lap 52 of one bottom panel 12 nests within or interlocks with a side lap 54 of an adjacent bottom panel 12 . By the term nesting, it is meant that the length of one side lap 52 fits within and follows closely with the length of the other side lap 54 , that the contours of one side lap 52 follow closely in the same directions and has the same changes in direction as the contours of the other side lap 54 . By the term interlocking, it is meant that a portion of one side lap 52 , is crimped to the other side lap 54 so that the materials of which the two side laps 52 , 54 , are made penetrates each others boundaries.
Bottom panel 12 may be perforated so as to have an array of holes 58 formed therein for absorbing sounds (see FIGS. 2A and 2B ) into cells 50 .
Bottom panel 12 has at least one, and preferably more than one, dove-tail shaped recesses 60 formed therein, and may have two dovetail recesses 60 for each top hat profile 16 of deck unit 8 in registration with each cell 50 . Recesses 60 may be concave upward or concave downward. Recesses are concave upward when viewed from below bottom panel 12 as they extend into cells 50 , as shown in FIG. 2A . Dovetail recesses 60 have narrow openings 64 and may extend concave downward, to the exterior of cell 50 below bottom panel 12 expanding in the downward direction, as shown in FIG. 2B .
Bottom panel 12 at dove-tail recesses 60 provide a nearly-closed, well-defined, protected conduit for piping, wiring, cables, optic fibers or sound insulating material 62 ( FIGS. 2A and 2B ). Bottom panel 12 at recesses 60 may be used to support vertical loads from below bottom panel 12 , such as signage 68 and lighting 70 (see FIG. 3 ).
FIG. 3 illustrates a deck system 72 formed of at least two deck units 74 , each defined by two top hat profiles 76 with a dovetail bottom panel 78 . As illustrated in FIG. 3 , a layer of concrete 80 overlays deck system 72 when deck system 72 is to function as a composite roof or floor.
In addition, employing bottom panels 12 with dove-tail recesses 60 attached to a top hat profile adds significantly to the strength of deck system 72 and allows for longer spans as well as greater functionality. Recesses 60 may be open and concave upward as illustrated in FIGS. 2A and 3 or closed and concave downward, as illustrated in FIG. 2B . If concave upward, the top of the dove-tail recesses may be used as added support for metal deck struts 90 , as disclosed in application Ser. No. 11/347,484 filed Feb. 3, 2006 for a metal deck strut system, as seen in FIG. 4 , which is identical to FIG. 1 except for the addition of struts 90 .
The superior strength of the present invention over an otherwise similar bottom panel with dove-tail recesses alone, is illustrated by the following example. Assuming a uniform load of 30 pounds per square foot and using 20 gauge steel, the span limit of a dovetailed panel is 12.5 feet. With a 20 gauge steel top hat profile attached to the dove-tailed panel, the span limit for the same loading increases to 20.5 to 26.5 feet depending on the height of the hat profile.
In addition to its great strength, the present invention also adds to the functional aesthetics of a ceiling of a building covering a large area, such as an airport terminal or an arena. The concave upward dovetail recesses establish narrow gaps in the otherwise smooth panel liners to create a plank look from below. This plank look gives the viewer a better indication of the perspective of the area as well as provides an aesthetically-pleasing, clean-looking treatment to the ceiling. Concave downward dovetail recesses provide wider gaps which provide a similar visual effect. In both cases (concave upward and concave downward dove-tail recesses) the bottom panel also hides the sidelap connections between adjacent deck units.
Dove-tail recesses also provide a convenient way to suspend lighting fixtures and signage, to serve as a hidden chase way for electrical or plumbing purposes, and as a sound-absorbing chamber or place for inserting acoustic materials for absorbing sounds from below.
Those familiar with steel deck system construction will appreciate that many modifications and substitutions can be made to the foregoing preferred embodiments of the present invention without departing from the spirit and scope of the present invention, defined by the appended claims. | A deck system is made by joining deck units, each having a hat-shaped profile fastened to the topside of a profiled bottom panel. The bottom panel has nestable or interlocking side laps and one or more “dove-tail” shaped recesses formed therein. These recesses, which may be concave upward or downward, give the deck unit additional strength as a defined, confined location for use to run conduit and to provide vertical support for vertical loads. The deck system may be combined with a layer of concrete for use as a floor or roof. | 4 |
BACKGROUND
Exemplary embodiments relate generally to managing network elements, and more particularly to managing voice over Internet protocol (VoIP) network elements.
Although VoIP technology has been in the market for several years, its service assurance for performance, reliability, and maintenance automation is relatively new in the network management arena. VoIP billing records, referred to as call detail records (CDRs), from multiple network equipment vendors are used separately to monitor and proactively respond to network or service impacting events. Without a common correlation identifier for CDRs among all VoIP network elements, it is difficult to produce an accurate end-to-end view of a telephone call. Network managers are forced to use inexact methods to correlate events, such as relating in-going and out-going Internet Protocol (IP) addresses. These inexact methods can lead to inaccurate call statistics for the entire VoIP network and for each service supported in the VoIP network. In addition, the performance alerts generated from each type of network element may not reflect the actual trouble area.
BRIEF SUMMARY
Exemplary embodiments include a method for managing VoIP network elements. The method includes receiving call details records (CDRs) from a plurality of network elements. The received CDRs include disconnect cause codes and telephone call correlation identifiers. The received CDRs are correlated to telephone calls based on the telephone call correlation identifiers. Two CDR records are associated with the same telephone call when their telephone call correlation identifiers are the same. A master correlated CDR is created for each telephone call. The creating includes assigning a correlated disconnect cause code and classifying the telephone call. The assigning and classifying are responsive to the received CDRs associated with the telephone call. The master correlated CDR includes the correlated disconnect cause code and the telephone call classification. A threshold crossing alert (TCA) is generated in response to a threshold for the correlated disconnect cause code being reached.
Additional exemplary embodiments include a system for managing VoIP network elements. The system includes a CDR collector machine receiving CDRs from a plurality of network elements. The received CDRs include disconnect cause codes and telephone call correlation identifiers. The system also includes a master correlated CDR machine that correlates the received CDRs to telephone calls based on the telephone call correlation identifiers. Two CDR records are associated with the same telephone call when their telephone call correlation identifiers are the same. The master correlated CDR machine also creates a master correlated CDR for each telephone call. The creating includes assigning a correlated disconnect cause code and classifying the telephone call. The assigning and classifying are responsive to the received CDRs associated with the telephone call. The master correlated CDR includes the correlated disconnect cause code and the telephone call classification. The system also includes an alert processing machine generating a TCA in response to a threshold for the correlated disconnect cause code being reached.
Further exemplary embodiments include a computer program product, tangibly embodied on a computer readable medium, for managing VoIP network elements. The computer program product has instructions for causing a computer to execute a method, which includes receiving call details records (CDRs) from a plurality of network elements. The received CDRs include disconnect cause codes and telephone call correlation identifiers. The received CDRs are correlated to telephone calls based on the telephone call correlation identifiers. Two CDR records are associated with the same telephone call when their telephone call correlation identifiers are the same. A master correlated CDR is created for each telephone call. The creating including assigning a correlated disconnect cause code and classifying the telephone call. The assigning and classifying are responsive to the received CDRs associated with the telephone call. The master correlated CDR includes the correlated disconnect cause code and the telephone call classification. A threshold crossing alert (TCA) is generated in response to a threshold for the correlated disconnect cause code being reached.
Other systems, methods, and/or computer program products according to exemplary embodiments will be or become apparent to one with skill in the art upon review of the following drawings and detailed description. It is intended that all such additional systems, methods, and/or computer program products be included within this description, be within the scope of the exemplary embodiments, and be protected by the accompanying claims.
BRIEF DESCRIPTION OF DRAWINGS
Referring now to the drawings wherein like elements are numbered alike in the several FIGs.:
FIG. 1 illustrates a high level view of a process for managing VoIP network elements that may be implemented by exemplary embodiments;
FIG. 2 illustrates a block diagram of a system that may be implemented by exemplary embodiments to manage VoIP network elements;
FIG. 3 illustrates a process flow for managing VoIP network elements that may be implemented by exemplary embodiments; and
FIG. 4 illustrates a process flow for creating correlated CDRs that may be implemented by exemplary embodiments.
The detailed description explains the exemplary embodiments, together with advantages and features, by way of example with reference to the drawings.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Exemplary embodiments provide, as part of voice over Internet protocol (VoIP) network maintenance automation, an accurate end-to-end view of a telephone call as it travels through the network. This end-to-end view of the telephone call is created by utilizing a common telephone call correlation identifier (ID) for call detail records (CDRs) among all VoIP network elements utilized by the telephone call. The common telephone call correlation ID is utilized to generate a master correlated CDR that reflects the CDRs generated by the network elements utilized by the telephone call. In exemplary embodiments, the common telephone call correlation ID is also utilized to provide an end-to-end view of threshold crossing alerts, and to generate call statistics and reports.
FIG. 1 illustrates a high level view of a process for managing VoIP network elements that may be implemented by exemplary embodiments. VoIP CDRs are generated by network elements (e.g., border elements, central control elements, and application servers) in a VoIP network 102 . A CDR provides detailed information about telephone calls that originate from, terminate at, or pass through each network element in the VoIP. In exemplary embodiments, the CDRs include information that may be utilized for billing such as, but not limited to: arrival time at network element, exit time from network element, record type, disconnect cause code, and telephone call correlation ID. The CDRs are received at a CDR processing module/system 104 to perform CDR collection, correlation, analysis, alerting and reporting.
The CDR processing module/system 104 generates threshold crossing alerts (TCAs) (also referred to herein as TCA performance alerts) when specified thresholds are exceeded. TCA performance alerts may be generated for network conditions such as blockage, cutoff, busy, packet loss, particular disconnect cause codes, data not ready, and ring no answer. In exemplary embodiments, the TCA performance alerts are fed into an alarm correlations module/system 106 along with VoIP network traps (also referred to herein as native traps) from the network elements. The alarm correlations module/system 106 correlates the network element native traps and the TCA performance alerts and generates correlated alerts that are fed into a rules module/system 108 . The rules module/system 108 includes additional rules for further alarm reduction. The rules module/system 108 generates alerts that are fed into a ticketing module/system 110 for generating service tickets that in exemplary embodiments are sent to a work center for evaluation and/or trouble-shooting.
FIG. 2 illustrates a block diagram of a system that may be implemented by exemplary embodiments to manage VoIP network elements. The system includes several network elements 202 , each generating a CDR 210 having data that includes a telephone call correlation ID (labeled “Corr. ID X”) and a disconnect cause code (labeled “DC#”). In the system depicted in FIG. 2 , a fault occurs at the network element 202 labeled “NE4.” In the exemplary embodiment depicted in FIG. 2 , the correlation IDs are the same for all of the CDRs 210 because they all are associated with the same telephone call in the VoIP network. In exemplary embodiments, the disconnect cause codes differ depending on the type of network element, the network element vendor, and the stage of progress of the call. Disconnect cause codes may include, but are not limited to: blockage, cutoff, busy, packet loss, particular disconnect cause codes, data not ready, and ring no answer
As depicted in FIG. 2 , the CDRs 210 are collected by a CDR collector machine 204 . As used herein, the term “machine” refers to computer software and/or hardware elements. The CDR collector machine 204 sends the CDRs 210 to a master correlated CDR machine 206 . The master correlated CDR machine 206 creates master correlated CDRs 212 for each telephone call and transmits them to alert processing and reporting machines 208 . In exemplary embodiments, the master correlated CDRs 212 include a correlated disconnect cause code and a telephone call classification. Additional data may also be provided in the master correlated CDR 212 such as telephone call start and stop time, record type, call direction and network element node name list. In exemplary embodiments, the CDR collector machine 204 , the master correlated CDR machine 206 , and the alert processing and reporting machines 208 make up the CDR processing module/system 104 depicted in FIG. 1 .
In exemplary embodiments, the alert processing and reporting machines 208 generate reports based on the master correlated CDRs 212 . Exemplary embodiments generate master correlated CDR detail reports autonomously to alleviate human intervention. In addition, exemplary embodiments include allowing a report requestor (e.g., a user) to query and view the master correlated CDR data. In further exemplary embodiments, the report requestor may filter, sort, perform trend analysis, transfer, and/or electronically mail the reports.
In exemplary embodiments, the master correlated CDRs 212 are stored for a configurable time period to avoid the necessity of storing individual network element CDRs 210 .
In exemplary embodiments, the alert processing and reporting machines 208 perform master correlated CDR analysis and overall call statistics generation based on the master correlated CDRs 212 . Derived overall telephone call statistics may be generated based on: per call classification, per call direction (e.g., from PSTN to VoIP, from VoIP to VoIP), per call service (e.g, business VoIP), total call attempts, and other criteria. In addition, other overall statistics such as average holding time per call direction and per service may be derived. Statistics derived from the individual network element CDRs 210 and the master correlated CDRs 212 may be stored for a configurable period of time.
FIG. 3 illustrates a process flow for managing VoIP network elements that may be implemented by exemplary embodiments. At block 302 , CDRs, such as the CDRs 210 from a plurality of network elements 202 are received at the CDR collector machine 204 . The CDRs 210 are associated with one or more telephone calls via the common telephone call correlation ID that is assigned by the network elements 202 when CDRs, such as the CDRs 210 are created. At block 304 , the received CDRs 210 are correlated to the telephone calls by the master correlated CDR machine 206 . The CDRs 210 that have the same telephone call correlation ID are associated with the same telephone call. At block 306 , a master correlated CDR 212 , such as the master correlated CDR 212 , is created for each telephone call by the master correlated CDR machine 206 . In exemplary embodiments, the master correlated CDRs 212 include a correlated disconnect cause code and a telephone call classification.
At block 308 in FIG. 3 , a TCA is generated if a performance threshold has been reached. As described previously, TCA performance alerts may be generated for network conditions such as, but not limited to, blockage, cutoff, busy, packet loss, particular disconnect cause codes, data not ready, and ring no answer. The TCA is forwarded to the alarms correlations module/system 106 and rules system 108 for trouble ticket generation. In exemplary embodiment, thresholds on call failure data are set based on expert judgment on the likelihood of events of this type occurring. In other exemplary embodiments a feed of master correlated CDRs 212 is sent to a test system that has a set of trial thresholds implemented. Different network scenarios can then be implemented and sensitivity to the problem adjusted. In addition, a duplicate CDR feed of master correlated CDRs 212 from the live network can be sent to a test system to “soak test” a proposed set of thresholds. It can be appreciated that there is a fine line that needs to be tread between being sensitive to real network problems and generating a lot of false positives which flood network managers with a lot of alerts, which they eventually may become de-sensitized to.
In exemplary embodiments, thresholds are set in order to balance detection of real and persistent problems with generating so many alerts that network managers disregard them. Exemplary systems have the ability to perform persistence and aging processing with alerts being processed at regular specified intervals (e.g. five minutes). In exemplary embodiments, the first time a threshold is crossed in the specified interval, a decision to take no action may be made unless the same problem occurs in the next specified interval. In exemplary embodiments, the threshold for any problems with calls associated with “911” service are set to the lowest possible value in order to trigger an immediate alert. The number of specified intervals can be provisioned to wait after a threshold is crossed before triggering an alert. TCA alerts and corresponding clears are used to indicate that a problem no longer exists. The number of specified intervals can be configured to wait when the threshold for a particular alert is no longer crossed. Clears indicate to network managers that a problem is no longer impacting the network but that they still may need to take some action to see if it may recur. Clear can be set up to automatically close trouble tickets or to remove alerts visually displayed on wall boards used by the network managers to monitor network health.
Master correlated CDRs 212 that indicate defects in associated entities can be aggregated. This includes such targets for aggregation as numbering plan area (area code), network element (e.g., switch), service (e.g., 911 calls, various business offerings), and disconnect code (e.g., timer expiration). Separate thresholds can be set for the number of defect calls aggregated against a node in a specified time period, an area code in a specified time period, and so forth. For example, it may be decided that, if there are one hundred telephone calls with the defect of blocked for a network element 202 within a specified time period, then a network element block alert will be generated if a specified number of additional telephone calls with a defective block are received. If after waiting a further specified time interval, the number of defects has stayed below the threshold of one hundred, then a clear is issued for the event.
FIG. 4 illustrates a process flow for creating master correlated CDRs 212 that may be implemented by exemplary embodiments. In exemplary embodiments, the process depicted in FIG. 4 is implemented by the master correlated CDR machine 206 depicted in FIG. 2 . At block 402 , all CDRs 210 received from network elements 202 with the same telephone call correlation ID are processed. In exemplary embodiments, the system may need to delay a time interval until all of the CDRs 210 for a telephone call are received. At block 404 , telephone call characteristics are determined based on contents of the CDRs 210 associated with the telephone call. In exemplary embodiments this includes characteristics such as earliest start time, latest stop time, record type (attempt or stop), call direction, network element node name list, disconnect cause code list, and other unique and common CDR fields of interest (e.g., to a particular vendor or network element). In exemplary embodiments, a record type of attempt means that the call failed and the disconnect cause code should be taken into account, and a record type of stop means that the call was successful.
In exemplary embodiments, an “n-field rule” that uses the values of a subset of “n” fields in the master correlated CDR 212 is utilized to assign the correlated disconnect cause code and to classify the telephone call. At block 406 , a correlated disconnect cause code is assigned to the master correlated CDR 212 . In exemplary embodiments, the correlated disconnect codes include, but are not limited to: blockage, cutoff, busy, packet loss, particular disconnect cause codes, data not ready, and ring no answer. The individual disconnect codes in the CDRs 210 are examined and a set of rules is implemented. Typically, when something goes wrong in a chain of network elements handling a call, the disconnect code for the failed network element 202 is the most informative. Disconnect codes from network elements 202 previous to it may indicate a success or failure; and network elements 202 after the failed network element 202 will either echo the failed network element's disconnect code or pass along their particular version of it. The chain of disconnect codes on the CDRs 210 are examined to find the first failure. The correlated disconnect code typically reflects the disconnect code of the first failed network element 202 in the chain of network elements handling the telephone call.
An example of a call characteristic is duration time; if all of the calls are suddenly staying up for only a short period of time there may be a problem. Another example call characteristic is packet loss; it may indicate that the call stayed up, but that the audio quality was poor. Often, CDRs 210 contain embedded billing information that relate the call to a particular network provider offering and this can be utilized to indicate that a particular network provider service is having a problem.
At block 408 , a call classification is assigned to the master correlated CDR 212 . Call classifications include, but are not limited to: ring no answer, busy, successful, blocked, and cutoff In exemplary embodiments, the CDR n-field rules described previously are utilized to classify the calls. For example, one of the “n-fields” indicates whether the call was successful or that it had failed. If the call failed, then another field of the “n-fields” indicates what the problem is related to. It could indicate that the call is related to a block (i.e., the call never even gets set up to the point where user communication takes place), or that the call was “cut-off” (the call got set up okay, but it was terminated due to something other than satisfied users hanging up the phone). Various disconnect codes (more of the n-fields) indicate if the call was a ring no answer, busy, or successful. Other parameters, such as call direction (e.g., VoIP-to-PSTN, PSTN-to-VoIP, VoIP-to-VoIP) help isolate the problem to the VoIP network platform, or the public switched telephone network (PSTN). In exemplary embodiments, a disconnect initiator indicates if the calling party, the called party, or the switch hung up the call. If the call direction is PSTN-to-VoIP and the call terminator is always the called party, and this seems to be happening in excess, then there may be a problem with the VoIP network.
Technical effects and benefits of exemplary embodiments include the ability to utilize a common correlation ID for the CDR 210 from different network elements 202 and different network element vendors. Thus, a master correlated CDR, such as the master correlated CDR 212 , may be generated based on information from the CDR 210 from multiple network elements 202 utilized by a telephone call. This allows for an accurate end-to-end view of call statistics and reporting. In addition, this may lead to a reduction in the amount of time required to analyze performance alerts.
As described above, exemplary embodiments can be in the form of computer-implemented processes and apparatuses for practicing those processes. Exemplary embodiments can also be in the form of computer program code containing instructions embodied in tangible media, such as floppy diskettes, CD ROMs, hard drives, or any other computer-readable storage medium, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the exemplary embodiments. Exemplary embodiments can also be in the form of computer program code, for example, whether stored in a storage medium, loaded into and/or executed by a computer, or transmitted over some transmission medium, loaded into and/or executed by a computer, or transmitted over some transmission medium, such as over electrical wiring or cabling, through fiber optics, or via electromagnetic radiation, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the exemplary embodiments. When implemented on a general-purpose microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits.
While the present disclosure has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from the essential scope thereof. Therefore, it is intended that the present disclosure not be limited to the particular exemplary embodiments disclosed for carrying out this invention, but that the present disclosure will include all embodiments falling within the scope of the claims. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. | Methods, computer program products, and systems for managing VoIP network elements are provided. Methods include receiving call details records (CDRs) from a plurality of network elements. The received CDRs including disconnect cause codes and telephone call correlation identifiers. The received CDRs are correlated to telephone calls based on the telephone call correlation identifiers. Two CDR records are associated with the same telephone call when their telephone call correlation identifiers are the same. A master correlated CDR is created for each telephone call. The creating includes assigning a correlated disconnect cause code and classifying the telephone call. The assigning and classifying are responsive to the received CDRs associated with the telephone call. The master correlated CDR includes the correlated disconnect cause code and the telephone call classification. A threshold crossing alert (TCA) is generated in response to a threshold for the correlated disconnect cause code being reached. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a Continuation-in-Part of U.S. patent application Ser. No. 12/124,191, entitled “Reduced Weight Decontamination Formulation for Neutralization of Chemical and Biological Warfare Agents”, filed on May 21, 2008, which application is a Continuation-in-Part of U.S. patent application Ser. No. 10/251,569, filed on Sep. 20, 2002, now U.S. Pat. No. 7,390,432, and the specifications thereof are incorporated herein by reference.
FEDERALLY SPONSORED RESEARCH
The United States Government has rights in this invention pursuant to Department of Energy Contract No. DE-AC04-94AL85000 with Sandia Corporation.
BACKGROUND OF THE INVENTION
Sandia National Laboratories has previously developed DF-200, an enhanced aqueous decontamination formulation for the neutralization of chemical and biological warfare agents and biological pathogens.
Two formulations associated with DF-200 are summarized below:
DF-200HF (Enhanced Formulation for High Foam Applications):
2.0% Variquat 80MC (cationic surfactant)
1.0% Adogen 477 (cationic hydrotrope)
0.4% 1-Dodecanol (fatty alcohol)
2.0% Polyethylene Glycol 8000 (polymer)
0.8% Diethylene Glycol Monobutyl Ether (solvent)
0.5% Isobutanol (solvent)
5.0% Bicarbonate salt (buffer and peroxide activator)
3.5% Hydrogen Peroxide (oxidant)
2.0% Propylene Glycol Diacetate or Glycerol Diacetate (peroxide activator)
10.0% Propylene Glycol (organic stabilizer)
˜2.0% Potassium Hydroxide (pH adjustment)
Water (Remainder—˜70%)
Note: The formulation can be adjusted to a pH value between 9.6 and 9.9; and is effective for decontamination of all agents tested.
DF-200NF (Enhanced Formulation for No Foam Applications):
2.0% Benzalkonium Chloride 2.0% Propylene Glycol Diacetate or Glycerol Diacetate 3.5% Hydrogen Peroxide 5.0% Potassium Bicarbonate 10.0% Propylene Glycol (organic stabilizer) ˜2.0% Potassium Hydroxide Water (Remainder—˜75%)
A new form of the Sandia National Laboratories decontamination formulation (DF-200) is needed to meet the CBW agent decontamination requirements of the US Department of Defense (DoD), and other potential users, for significantly reduced weight and volume burdens. Of primary interest and benefit to the warfighter is the use of one formulation for battlefield and fixed site decontamination that is easily deployable, fast reacting, environmentally friendly with low toxicity and corrosivity properties, and that has a low logistics burden. Currently, the aqueous-based DF-200 is provided in an ‘all-liquid’ configuration where all water is included within the packaged formulation. The current decontamination formulation of the US DoD (EasyDECON™-200 and MDF-200 which are based on Sandia National Laboratories DF-200 Decontamination Formulation) contains approximately 75% water and is packaged, shipped, and stored with all the water as part of the formulation. Although this configuration of DF-200 makes it simple to use (by quickly mixing each of the three liquid parts) it requires a significant logistics burden since each gallon of the formulation weighs approximately 9 lbs.
A new configuration of the decontamination formulation is needed that can be packaged as a dry kit, with most or all water removed, thereby reducing the packaged weight of the decontamination formulation by ˜80% (as compared to the “all-liquid” DF-200 formulation) and significantly lowering the logistics burden on the warfighter. Water (freshwater or saltwater) would be added to the new decontamination formulation configuration at the time of use from a local source.
Currently, standard DF-200 is used by the military in an ‘all-liquid’ configuration consisting of three parts:
Part A: Foam Component (˜49% by volume)—consists of surfactants, solvents, inorganic bases, and buffers dissolved in water; Part B: 8% Hydrogen Peroxide Solution (˜49% by volume)—consists of hydrogen peroxide dissolved in water; and Part C: Liquid Peroxide Activator (˜2% by volume)—consists of an organic liquid.
As seen in the current formulations above, water makes up a substantial portion of DF-200 and, hence, it removal can achieve the desired weight savings. However, development of a reduced weight configuration of DF-200 (i.e., a ‘dry’ formulation) is a considerable technical challenge. Ideally, a ‘dry’ formulation would have the following desirable characteristics:
high storage stability in extreme temperature environments; rapid solubility of the ingredients in both freshwater and saltwater; low cost (e.g., use of commercially available ingredients); high efficacy against both chemical and biological warfare agents; ability to maintain sufficient contact time between the formulation and the agents on both vertical and horizontal surfaces in all deployment conditions; ability to be easily deployed with existing military equipment.
To accomplish these objectives, the development of a reduced weight decontamination formulation utilizing a solid peracid compound focused on three tasks:
evaluation of the sodium borate peracetate material to determine its stability under high temperature storage conditions; selection of ingredients to extract chemical and biological warfare agents from contaminated material surfaces into the decontamination formulation for subsequent neutralization (i.e., selection of surfactants for incorporation into the decontamination formulation); and selection of ingredients to enable the decontamination formulation to maintain sufficient contact time on a surface to achieve the required efficacy against chemical and biological warfare agents.
SUMMARY OF THE INVENTION
The present invention relates to a reduced weight decontamination formulation that utilizes a solid peracid compound (sodium borate peracetate) that can be packaged with all water removed. This reduces the packaged weight of the decontamination formulation by ˜80% (as compared to the “all-liquid” DF-200 formulation) and significantly lowers the logistics burden on the warfighter. Water (freshwater or saltwater) is added to the new decontamination formulation at the time of use from a local source.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and form part of the specification, illustrate various examples of the present invention and, together with the detailed description, serve to explain the principles of the invention.
FIG. 1 : Results from oven stability testing on sodium borate peracetate.
FIG. 2 : Oxidative attack of a chemical agent with low water solubility within a cationic micelle in the decontamination formulation.
FIG. 3 : Nucleophiles are repelled by anionic micelles and do not attack an insoluble toxic chemical agent.
FIG. 4 : Remaining spores following a 15 and 60 minute exposure to the reduced weight decontamination formulation with de-ionized water and saltwater as the make-up water.
DETAILED DESCRIPTION OF THE INVENTION
The use of powdered additives to ‘dry-out’ some components certain ingredients of standard DF-200 formulations has been described in detail in commonly-owned U.S. Pat. Nos. 7,276,468 and 7,282,470 to Tucker, which are both incorporated herein by reference.
Neutralization is defined as the mitigation, de-toxification, decontamination, or otherwise destruction of TICs to the extent that the TICs no longer cause adverse health effects to humans or animals. The present invention addresses the need for decontamination formulations that are non-toxic, non-corrosive, lost-cost, long shelf-life, and that can be delivered by a variety of means and in different phases, including sprays, foams, fogs, mists, aerosols, gels, creams, pastes, baths, strippable coatings, etc.
The word “formulation” is defined herein as the made-up, “activated” product or solution (e.g., aqueous decontamination solution) that can be applied to a surface or body, or dispersed into the air, etc. for the purpose of neutralization, with or without the addition of a gas (e.g., air) to create foam. Unless otherwise specifically stated, the concentrations, constituents, or components listed herein are relative to the weight percentage of the made-up, activated aqueous decontamination solution. The word “water” is defined herein to broadly include: pure water, tap water, well water, waste water, deionized water, demineralized water, saltwater, or any other liquid consisting substantially of H 2 O.
Evaluation of the High Temperature Stability of Sodium Borate Peracetate
A primary consideration for the reduced weight decontamination formulation was to identify a solid oxidant material that is stable under high temperature storage conditions. In this case, the focus was on the peracid compound: sodium borate peracetate, Na 2 B 4 O 5 (OH) 4 .2CH 3 COOH 2CH 3 COO 2 H, also known as peracetyl borate (PAB), PES-SOLID, PBS-AC, and Sodium borate: peroxyacetic acid adduct; and has a molecular weight of 509.5. Two different sodium borate peracetate samples were obtained—one from the US DoD and one from Solvay, Inc (the manufacturer of the compound). Oven testing was initiated to test this material. The compound was placed in an oven that cycled between 30° C. and 70° C. on a 24-hour basis. The compound was placed in glass vials with plastic lids. The plastic lids were loosened slightly to provide a mechanism for pressure relief in the vials. Small samples of sodium borate peracetate were extracted from the oven approximately every seven days and the samples were analyzed for peracetic acid content via a titration method to determine if any degradation occurred. The results from the oven tests are shown in FIG. 1 . The results show that sodium borate peracetate is relatively stable under these conditions. It retained approximately 80% of its original peracetic acid content even after 120 days of exposure to the high temperature storage conditions.
Description of Reaction Mechanisms in the Decontamination Formulation
The primary mechanism for detoxification of chemical agents in this decontamination formulation involves the principle of micellar catalysis. This principle is illustrated for a chemical agent that has low solubility in water that may be detoxified by nucleophilic or oxidative attack. A set of constituents has been selected in the decontamination formulation to provide a mechanism to solubilize the sparingly soluble chemical agent and to attract a reactive catalyst, dissolved in aqueous media, to a position in close proximity to the chemical molecule vulnerable to nucleophilic or oxidative attack. This is accomplished through the recognition that certain nucleophiles and oxidants are negatively charged. Therefore, the formulation contains cationic surfactants that form positively-charged micelles to solubilize the chemical agent and attract the negatively-charged nucleophile or oxidant such as hydroxyl ions (OH − ) and peracetate ions (RCOOO − ), which are released from the sodium borate peracetate.
FIG. 2 shows an example of a cationic micelle that is formed from cationic surfactants. In the aqueous environment, the insoluble toxic chemical agent is dissolved within the micelle comprised of an aggregate of surfactant molecules with hydrophobic tails forming the interior core of the micelle, and hydrophilic heads concentrating at the surface of the micelle. These positively charged hydrophilic heads attract the negatively charged oxidant (in this case, the peracetate ion) greatly enhancing the reaction rates with the insoluble chemical agent within the micelle.
This is contrasted with a formulation that is constructed with anionic surfactants such as those in a typical firefighting foam ( FIG. 3 ). Here, the negatively charged micelles repel the nucleophiles and oxidants so that neutralization of the insoluble chemical agent, which is dissolved in the micelle, does not occur.
In the present invention, sodium borate peracetate is combined with a cationic surfactant. The use of cationic surfactants creates a reaction mixture that utilizes micellar catalysis to achieve rapid reaction rates against the agents. It also allows for the use of a relatively low percentage of ingredients in the formulation (i.e., a high percentage of water) as compared to other formulations that use a microemulsion (i.e., a high percentage of the formulation is ingredients other than water). In the present invention, the use of a high percentage of water allows the formulation to be concentrated in a dry form, and having a reduced weight.
Reduced Weight Decontamination Formulation Components
The reduced weight decontamination formulation consists of a mixture of the following components:
Part A: Solid Sodium Borate Peracetate Material; Part B: Surfactant, Buffering, Foam Stabilizing, and Drying Ingredients; and Part C: Makeup Water—freshwater or saltwater supplied from a local source at the point of use
A first example of a formulation for decontamination of chemical and biological warfare agents is shown below. An optimal pH of the formulation is 8.6. The formulation represents approximately an 80% weight savings over the pervious ‘all-liquid’ DF-200 formulation.
EXAMPLE #1
Part A (Sodium Borate Peracetate)
40 g Solid Sodium Borate Peracetate
Part B (Surfactant Buffering Foam Stabilizing and Drying Ingredients)
11 g Dodecyltrimethylammonium Chloride
4 g Tripropylene Glycol Methyl Ether
2 g 1-Dodecanol
10 g Potassium Bicarbonate
30 g Potassium Carbonate
20 g Sorbitol (Sorbigem™ Fines)
Part C (Makeup Water)
500 g Water (Freshwater or Saltwater).
Total=617 grams.
To prepare Part B, use the following method:
1. Add Tripropylene glycol methyl ether to an empty vessel.
2. Add dodecyltrimethylammonium chloride. Stir until dispersed throughout liquid and all lumps are dissolved.
3. Add 1-dodecanol. Stir (a paste will form).
4. Add sorbitol and stir.
5. Add potassium bicarbonate and potassium carbonate. A free flowing powder will result.
To prepare the formulation, use the following method.
1. Add Part C (makeup water) to an empty vessel.
2. Add Part A. Stir vigorously until dissolved.
3. Add Part B. Stir vigorously until dissolved.
4. The formulation is ready for use. The pH of the formulation should be approximately 8.6. Optimal deployment is through a compressed air foam generating system.
Example # 2 has the same ingredients as in Example #1, with the concentration shown in weight percentage (wt %) amounts:
EXAMPLE #2
Part A (Sodium Borate Peracetate)
6.5 wt % Solid Sodium Borate Peracetate
Part B (Surfactant, Buffering, Foam Stabilizing, and Drying Ingredients)
1.8 wt % Dodecyltrimethylammonium Chloride
0.6 wt % Tripropylene Glycol Methyl Ether
0.3 wt % 1-Dodecanol
1.6 wt % Potassium Bicarbonate
4.9 wt % Potassium Carbonate
3.3 wt % Sorbitol (Sorbigem™ Fines)
Part C (Makeup Water)
81.0 wt % Water (Freshwater or Saltwater)
Total=100%
Reduced weight DF-200 formulations can be packaged, stored, and transported to the point of use in the form of a two-part kit (i.e., Parts A and B, each packaged separately in individual containers). Then, at the point of use, the makeup water (Part C) is added.
Alternatively, the two pre-packaged dry parts (A and B) can be pre-mixed together to form a single dry mixture, however the storage stability may be reduced due to some interaction between the ingredients. This would not be a problem for some applications where a short shelf life would be acceptable.
The reduced weight formulation could also be used for other disinfection and neutralization applications where the toxic chemical or biological compounds are less resistant and/or less toxic than chemical warfare agents such as GD, VX, or HD or biological warfare agents such as anthrax spores. Examples of these applications include inactivation of viruses (e.g., avian influenza, smallpox, foot and mouth disease, etc.) or vegetative cells (e.g., E. coli, salmonella , etc.) or neutralization of toxic industrial chemicals (e.g., sodium cyanide). In this case, the concentrations of the ingredients of the formulation could be reduced in the ranges shown below:
EXAMPLE #3
Part A (Sodium Borate Peracetate)
5-40 g Solid Sodium Borate Peracetate
Part B (Surfactant, Buffering, Foam Stabilizing, and Drying Ingredients)
1-11 g Dodecyltrimethylammonium Chloride
0-4 g Tripropylene Glycol Methyl Ether
0-2 g 1-Dodecanol
5-40 g Potassium Bicarbonate
5-40 g Potassium Carbonate
0-20 g Sorbitol (Sorbigem™ Fines)
Part C (Makeup Water)
500 g Water (Freshwater or Saltwater)
Example # 4 has the same ingredients as in Example #3, with the concentration shown in weight percentage (wt %) amounts:
EXAMPLE #4
Part A (Sodium Borate Peracetate)
0.8-6.5 wt % Solid Sodium Borate Peracetate
Part B (Surfactant, Buffering, Foam Stabilizing, and Drying Ingredients)
0.1-1.8 wt % Dodecyltrimethylammonium Chloride
0-0.6 wt % Tripropylene Glycol Methyl Ether
0-0.3 wt % 1-Dodecanol
0.8-1.6 wt % Potassium Bicarbonate
0.8-4.9 wt % Potassium Carbonate
0-3.3 wt % Sorbitol (Sorbigem™ Fines)
Part C (Makeup Water)
81-97.5 wt % Water (Freshwater or Saltwater)
Total=100%
Substitutions for the various ingredients can be made. In Part B, the solvent (Tripropylene glycol methyl ether) can be replaced by other solvents, such as hexylene glycol, diethylene glycol methyl ether, or propylene glycol. In addition, the surfactant can be replaced by other cationic surfactants, such as other types of quaternary ammonium compounds (e.g., benzyl dodecyldimethyl ammonium chloride, didecyldimethylammonium chloride), amine alkoxylates (e.g., polyethylene glycol cocoamine), and amine oxides (e.g., lauric dimethylamine oxide). However, it was determined through a series of tests, that dodecyltrimethylammonium chloride provides superior efficacy as compared to other cationic surfactants so it is considered to be the surfactant for use in the preferred formulation. Potassium bicarbonate and potassium carbonate can be replaced by other buffering and pH adjustment ingredients including other bicarbonate and carbonate salts (e.g., sodium, ammonium, etc.), borate salts (e.g., sodium, potassium), phosphate salts (e.g., sodium and potassium), and acetate salts (e.g., sodium and potassium).
The sorbent additive, sorbitol, used as a drying ingredient, can also be replaced with another sorbent selected from the group consisting of zeolytes, precipitated silica, fumed silica, dendritic salt, sea salt, polyethylene glycol, urea, sodium gluconate, potassium gluconate, and polyols.
Examples of suitable polyols that may be used as the sorbent additive include
Sorbitol, Mannitol, Hydrogenated Starch Hydrolysates (HSH), Maltitol, Zylitol, Lactitol Monohydrate, Anhydrous Isomalt, Erythritol, and Polydextrose.
The polyols listed above are sugar-free sweeteners. They are carbohydrates, but they are not sugars. Chemically, polyols are considered polyhydric alcohols or “sugar alcohols” because part of the structure resembles sugar and part is similar to alcohols. However, these sugar-free sweeteners are neither sugars nor alcohols, as those words are commonly used. They are derived from carbohydrates whose carbonyl group (e.g., aldehyde or ketone, reducing sugar) has been reduced to a primary or secondary hydroxyl group.
The most widely used polyols in the food industry are sorbitol, mannitol, and malitol. Sorbitol is derived from glucose; mannitol from fructose; and malitol from high maltose corn syrup. Sorbogem™ and Mannigem™ are product names for sorbitol and mannitol sold by SPI Polyols, Inc., and are available in a wide range of particle size, down to fine sizes (i.e., Sorbogem Fines™).
Sorbitol is a hexahydric alcohol (C 6 H 14 O 6 ) corresponding to glucose, and has a molecular weight of 182.2. It occurs naturally, and is also produced by the hydrogenation of glucose syrup in the presence of Raney Nickel Catalyst. Some synonyms for sorbitol include: cholaxine, clucitol, diakarmon, gulitol, I-gulitol, karion, nivitin, sionit, sorbicolan, sorbite, d-sorbitol, sorbo, sorbol, sorbostyl, sorvilande. Sorbitol has a CAS No. 50-70-4 and an EC No. 200-061-5. The sorbent additive may be selected to be a “G.R.A.S.” material, meaning that it is Generally Recognized As Safe to be used in this and other applications.
Efficacy Testing of the Reduced Weight Formulation
The performance of the preferred reduced weight decontamination formulation (Example #1) for neutralization of chemical agent simulants is shown in Table 1 with de-ionized water used as the make-up water (Part C). These tests were conducted in a solution of the formulation at a decon-to-simulant ratio of 200:1. The results are compared to the standard “all-liquid” version of DF-200.
TABLE 1 Concentration (wt %) of remaining simulant in solution tests of the reduced weight decontamination formulation Example #1. VX Simulant HD Simulant 1 15 60 1 15 60 Formulation Min. Min. Min. Min. Min. Min. DF-200 (All-Liquid) 81.6 ND >99.9 67.6 98.6 ND Reduced Weight Formulation 98.0 99.1 >99.9 95.7 96.6 ND Example #1
Tests against the anthrax spore simulant ( Bacillus globigii spores) demonstrated 99.9999% (7−log) kill after a 15 and 60 minute exposure to the preferred reduced weight decontamination formulation. The results are shown in FIG. 4 .
In another example, the decontamination formulation can comprise:
by weight percentage:
0.8-6.5 wt % Solid Sodium Borate Peracetate; 0.1-1.8 wt % cationic surfactant; 0-0.6 wt % solvent; 0-0.3 wt % 1-Dodecanol; 0.8-6.5 wt % buffering agent; 0-3.3 wt % sorbent additive; and water (remaining balance);
wherein the solvent is selected from the group consisting of Tripropylene glycol methyl ether, hexylene glycol, diethylene glycol methyl ether, and propylene glycol, and combinations thereof; wherein the cationic surfactant is selected from the group consisting of dodecyltrimethylammonium chloride, benzyl dodecyldimethylammonium chloride, didecyldimethylammonium chloride, amine alkoxylates, polyethylene glycol cocoamine, amine oxides, and lauric dimethylamine oxide, and combinations thereof; wherein the buffering agent is selected from the group consisting of sodium bicarbonate and carbonate salts, ammonium bicarbonate and carbonate salts, sodium or potassium borate salts, sodium or potassium borate phosphate salts, and sodium or potassium acetate salts, and combinations thereof; and wherein the sorbent additive is selected from the group consisting of selected from the group consisting of zeolytes, precipitated silica, fumed silica, dendritic salt, sea salt, polyethylene glycol, urea, sodium gluconate, potassium gluconate, and polyols, and combinations thereof.
The particular examples discussed above are cited to illustrate particular embodiments of the invention. Other applications and embodiments of the apparatus and method of the present invention will become evident to those skilled in the art. It is to be understood that the invention is not limited in its application to the details of construction, materials used, and the arrangements of components set forth in the following description or illustrated in the drawings.
The scope of the invention is defined by the claims appended hereto. | A reduced weight decontamination formulation that utilizes a solid peracid compound (sodium borate peracetate) and a cationic surfactant (dodecyltrimethylammonium chloride) that can be packaged with all water removed. This reduces the packaged weight of the decontamination formulation by ˜80% (as compared to the “all-liquid” DF-200 formulation) and significantly lowers the logistics burden on the warfighter. Water (freshwater or saltwater) is added to the new decontamination formulation at the time of use from a local source. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This Divisional U.S. Patent Application, filed under 37 C.F.R. § 1.53(b) and 35 U.S.C. § 121, claims the benefit of priority under 35 U.S.C. § 120 of U.S. patent application Ser. No. 10/877,659 (filed on 24 Jun. 2004), which claims the benefit under 35 U.S.C. § 119(e)(1) of U.S. Provisional Patent Application No. 60/482,097, filed under 35 U.S.C. § 111(b) on 24 Jun. 2003, each of which are hereby incorporated by reference in their entireties.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
[0003] Not applicable.
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON COMPACT DISC
[0004] Not applicable.
BACKGROUND OF THE INVENTION
[0005] 1. Field of the Invention
[0006] The present invention relates to a novel method of creating an immunogen and using it to produce antibodies against nonenveloped and enveloped viruses, bacterial pathogens, fungal pathogens, other microbial pathogens, and proteins. The invention relates generally to agents and methods for preventing a viral outbreak and, more specifically, to compositions containing a β-cyclodextrin (β-CD) and methods of using such compositions to decrease the probability and/or reduce the severity of a viral outbreak. The present invention also relates to a pharmaceutical composition, which includes β-CD, which is in a sufficient amount to block viral passage through lipid rafts in the membrane of nerve cells. The present invention further relates to a composition, comprising a solid substrate that contains an effective amount of β-CD useful for reducing viral release.
[0007] 2. Description of Related Art
[0008] The plasma membrane of immune and non-immune cells is composed of detergent insoluble domains called lipid rafts, which are membrane compartments enriched in cholesterol and sphingolipids. In some tissues these specialized domains are referred to as caveolae. The initiation and propagation of intracellular signaling events occurs in these specialized membrane regions. Lipid rafts also contain many lipid-modified signaling proteins, and restrict their diffusion. Some examples of proteins associated with lipid rafts are tyrosine kinases of the Src family, glycophosphatidylinositol (GPI)-linked proteins, as well as adaptor proteins.
[0009] The confinement of signaling molecules to membrane subdomains suggests that lipid rafts are platforms for the formation of multicomponent transduction complexes. When immune receptors bind to their ligands, they become associated with lipid rafts. Additional components of the receptor signaling pathways are subsequently recruited to the rafts and form macromolecular signaling complexes. The initial translocation of immune receptors into lipid rafts is an important step in regulating cell activation.
[0010] Numerous experiments have provided substantial evidence that the integrity of lipid rafts is crucial for the initiation and maintenance of intracellular signals. Depletion of cholesterol, a component of lipid rafts, has been shown to inhibit HIV infection and illustrates the importance of lipid rafts in viral infection. Virus fusion and entry involves sequential interactions between viral proteins and proteins of the cell surface. These fusion and entry interactions proceed via three-dimensional rearrangements of viral and cell-surface proteins, thus giving rise to novel, but transient antigenic features. The present invention exploits those unique antigenic features to create novel anti-viral antibodies.
[0011] Virus entry into host cells involves the specific interaction of virus with receptor molecules contained within. Virus assembly and increases in viral concentration also occur in lipid rafts. Thus, the interaction between virus particles and lipid rafts presents an environment in which novel viral epitopes may be exposed. The interaction of proteins and lipid rafts generates novel configurations of the proteins that may be exploited to produce novel antibodies against the protein.
[0012] The significance of detergent-insoluble, glycolipid-enriched membrane domains (“lipid rafts”) has been demonstrated, particularly in regard to activation and signaling in T lymphocytes. Lipid rafts can be viewed as floating rafts comprised of sphingolipids and cholesterol that sequester glycosylphosphatidylinositol (GPI)-linked proteins such as Thy-1 and CD59. CD45, a 200 kDa transmembrane phosphatase protein, is excluded from these domains. Human immunodeficiency virus type 1 (HIV-1) particles produced by infected T cell lines acquire the GPI-linked proteins Thy-1 and CD59, as well as the ganglioside GM1, which is known to partition preferentially into lipid rafts. In contrast, despite its high expression on the cell surface, CD45 is poorly incorporated into virus particles. Confocal fluorescence microscopy revealed that HIV-1 proteins colocalized with Thy-1, CD59, GM1, and a lipid raft-specific fluorescent lipid, DiIC16 (see below), in uropods of infected Jurkat cells. CD45 did not colocalize with HIV-1 proteins and was excluded from uropods. Dot immunoassay of Triton X-100-extracted membrane fractions revealed that HIV-1 p17 matrix protein and gp41 were present in the detergent-resistant fractions and that ( 3 H)-myristic acid-labeled HIV Gag protein showed a nine-to-one enrichment in lipid rafts. As disclosed herein, the budding of HIV virions through lipid rafts is associated with the presence of host cell cholesterol, sphingolipids, and GPI-linked proteins within these domains in the viral envelope, indicating preferential sorting of HIV Gag to lipid rafts (see Example 1).
[0013] Glycolipid-enriched membrane (GEM) domains are organized areas on the cell surface enriched in cholesterol, sphingolipids, and GPI-linked proteins. These domains have been described as “rafts” that serve as moving platforms on the cell surface (Shaw and Dustin, Immunity. 6:361-369, 1997). The domains, now referred to as “lipid rafts,” exist in a more ordered state, conferring resistance to Triton X-100 detergent treatment at 4° C. (Schroeder et al., J. Biol. Chem. 273: 1150-1157, 1998). Many proteins are associated with lipid rafts, including GPI-linked proteins, Src family kinases, protein kinase C, actin and actin-binding proteins, heterotrimeric and small G proteins, and caveolin (see, for example, Arni et al., Biochem. Biophys. Res. Commun. 225:8001-807, 1996; Cinek and Horejsi, J. Immunol. 149:2262-2270, 1992; Robbins et al., Mol. Cell. Biol. 15:3507-3515, 1995; and Sargiacomo et al., J. Cell. Biol. 122:789-807, 1993). Saturated acyl chains of the GPI anchor have been shown to be a determinant for the association of GPI-linked proteins with lipid rafts (Rodgers et al., Mol. Cell. Biol. 14:5384-5391, 1994; Schroeder et al., Proc. Natl. Acad. Sci., USA. 91: 12130-12134, 1994). Lipid rafts exclude certain transmembrane molecules, specifically the membrane phosphatase CD45 (Arne et al., supra, 1996; Rodgers and Rose, J. Cell. Biol. 135: 1515-1523, 1996). Exclusion of CD45 results in the accumulation of phosphorylated signaling molecules in lipid rafts, and T cell activation requires clustering of signaling molecules in these membrane domains (Lanzavecchia et al., Cell. 96: 1-4, 1999).
[0014] The role of lipid rafts in viral infection can further be extended to viruses other than HIV. For example, selective budding occurs for a virus of the influenza family, fowl plague virus, from ordered lipid domains (Scheiffele et al., J. Biol. Chem. 274:2038-2044, 1999, which is incorporated herein by reference). The requirement for cholesterol and sphingolipids in target membranes for Semliki Forest virus fusion also has been established (Nieva et al., EMBO J. 13:2797-2804, 1994; Phalen and Kielian, J. Cell Biol. 112:615-623, 1991, each of which is incorporated herein by reference). The interactions of lipid rafts with accessory HIV-1 molecules such as Vif and Nef can have important roles in virus budding, since interactions of myristylated HIV and simian immunodeficiency virus Nef with Lck, which is present in lipid rafts, and its incorporation into virions have been established (see, for example, Collette et al., J. Biol. Chem. 271:6333-6341, 1996; Flaherty et al., AIDS Res. Hum. Retrovir. 14:163-170, 1998).
[0015] Example 1 describes the interaction of HIV virus with lipid raft resident molecules such as GM1. The results disclosed in Example 1 indicate that HIV-1 buds through lipid rafts. During the course of infection, the cell becomes activated and polarization occurs, capping normally dispersed lipid rafts along with GPI-linked proteins and associated intracellular signaling molecules, and membrane areas containing CD45 can be cleared out of the cap site. The newly translated viral Gag precursor protein associated with lipid rafts then can be directed to the capped pole, where assembly and budding occurs. Palmitylated gp41 (gp160) is also directed into lipid rafts, and the interaction of its cytoplasmic tail with Gag protein in lipid rafts can prevent its internalization, allowing for the incorporation of gp160 into virions only at the site of budding (see Egan et al., J. Virol. 70:6547-6556, 1996; Yu et al., J. Virol. 66:4966-4971, 1992). Individual targeting of Gag and Env to the same site at the membrane can be an important means for delivering these proteins to the site of budding, since Gag and Env are processed and transported in different pathways within the cell. The host membrane then can become the new viral coat, resulting in the incorporation of cholesterol, sphingolipids, Thy-1, and CD59 and in the exclusion of CD45. HIV-1 also acquires functional adhesion molecules from host cells (Orentas and Hildreth, supra, 1993). These host-acquired proteins can significantly affect the biology of HIV-1 (see, for example, Fortin et al., J. Virol. 71:3588-3596, 1997).
BRIEF SUMMARY OF THE INVENTION
[0016] The present invention relates to a novel method of designing an immunogen and producing antibodies to nonenveloped and enveloped viruses, and proteins. Specifically, it uses the co-culture of purified lipid rafts and viral particles as an immunogen.
[0017] The present invention also relates to a novel therapeutic method of preventing viral outbreaks (budding), using β-cyclodextrins.
[0018] This invention provides a novel application for β-cyclodextrin, a cholesterol depletor, as an inhibitor of viral outbreak. Topical applications of β-cyclodextrin are recommended to inhibit or reduce the severity of viral outbreaks such as oral or genital herpes. This invention also provides a novel technique for the creation of immunogens. Viral entry and outbreak also occurs at specialized lipid raft domains and disruption of rafts with cholesterol depletors blocks viral entry and outbreak (budding). Lipid microdomains (lipid rafts) are mobile regions of the plasma membrane and exist in all mammalian cell membranes. They are produced by the preferential packing of cholesterol and sphingolipids into the plasma membrane and are identified by their low solubility in detergents and enrichment with gangliosides such as GM1. The size and composition of rafts can be dynamically altered during transmembrane signaling. Depletion of membrane cholesterol disrupts lipid rafts and inhibits viral entry and outbreak. Virus entry into cells involves virus/lipid raft interaction wherein the virus unfolds to enter the cell via the lipid raft. I provide a technique for the creation of an immunogen with novel viral epitopes based on the virus/lipid raft interaction and viral unfolding. Viral unfolding only occurs in lipid rafts. This fact can be exploited to create novel immunogens based on viral interaction with lipid rafts. The virus/lipid raft co-culture technique will create novel immunogens which will be used to create novel neutralizing monoclonal and polyclonal antibodies to fight viral disease such as HIV infection.
[0019] Viral entry into cells involves unfolding of the virus and penetration into the cell at specific lipid raft sites. Antibodies created against the lipid raft/virus co-culture exploit viral unfolding to reveal novel epitopes in the virus that may be exploited as immunogens to create novel neutralizing antibodies. Purified preparations of lipid rafts are easily prepared from primary lymphoctes or transformed lymphocytes such as the Jurkat cell line. Purified isolates of HIV obtained from infected cell supernatants can be co-cultured with purified fractions of lipid rafts. These co-cultures can be used intact as immunogens or partially proteolysed to create viral/raft fragments. Additionally, the viral/raft co-cultures can remain co-cultured intact or fixed while co-cultured in mild fixative such as paraformaldehyde or glutaraldehyde. The steps involve mixing purified raft fractions with isolated virus. This admixture of raft/virus serves as the novel immunogen. Antibodies created against the lipid raft/virus co-culture will recognize antigenic determinants of the virus unique to the lipid raft/virus interaction. The method employs lipid raft/virus or lipid raft/protein suspensions as immunogens to develop polyclonal or monoclonal antibodies. Alternatively, lipid raft fractions may be made from infected cells such as lymphocytes or an immune cell line such as Jurkat. Lipid rafts produced in this fashion would already contain interactive virus and would be ready for use as a raft/virus immunogen. A lipid raft/virus or lipid raft/protein co-cultured immunogen that will generate an antibody response able to neutralize a broad spectrum of primary viral isolates and generate immune responses is created in this fashion. Antibodies to novel epitopes in virus and proteins are also created in this fashion.
[0020] The use of lipid raft terminology in this disclosure also includes use of caveolae (i.e., cocultures of caveolae/virus or co-cultures of caveolae/protein) as immunogens. This method can also be applied to the co-culture of lipid rafts and any pathogen. As such, the pathogen can be an enveloped virus, including but not limited to an immunodeficiency virus such as human immunodeficiency virus, a T lymphocytic virus such as human T lymphocytic virus (HTLV), a herpes virus such as herpes simplex virus (HSV), a measles virus, or an influenza virus. The pathogen also can be a microbial pathogen, for example a bacterium, a yeast such as Candida, a mycoplasma, a protozoan such as Trichomonas, or a Chlamydia.
[0021] Lipid raft preparations are easily obtained from a variety of cell sources. Immune cells susceptible to viral infection represent good source for raft preparation. Whole immune cells exposed to virus could also be used as a source of lipid raft/virus immunogen. Co-culture combinations of lipid rafts, viral proteins and various peptides (e.g., the HIV envelope glycoprotein gp120) would also be used as immunogens. Thus, this method is also applicable to generating antibodies to novel conformations of viral, microbial, fungal, and animal proteins when co-cultured and interacting with lipid rafts.
[0022] Many proteins translocate into lipid rafts following stimulation. This translocation involves modifications such as palmitylation and/or myristylation. Antibodies raised against such lipid raft/protein immunogens may recognize novel epitopes in the translocated protein. Natural lipid raft/virus co-cultures will serve as immunogens, but lipid raft/virus co-cultures or whole cell/virus co-cultures fixed with low concentrations of fixative such as formalin, glutaraldehyde, or methanol may also be used. Lipid raft preparations can also be modified to include or exclude selected proteins in order to vary the immunogenic effect of the raft/virus, raft/protein co-culture. In a preferred embodiment, immunizations are performed in mice engineered to be transgenic for human antigens, thus reducing the possibility that the antibodies generated would recognize human proteins.
[0023] This novel method of immunogen production may prove useful in the generation of anti-viral vaccines. In the case of human immunodeficiency virus type 1 (HIV-1), success has been gauged by the ability of candidate immunogens to generate measurable immune responses in human volunteers and animal models. The two crucial responses have been the generation of virus-specific CD8 + cytotoxic T lymphocytes (CTLs), which attack and destroy infected cells, and production of neutralizing antibodies, which bind to the virus and prevent infection of new cells. For HIV-1, an effective anti-viral vaccine has remained elusive.
[0024] A number of studies published in recent years have shown that neutralizing monoclonal antibodies of the IgG class alone can be effective in blocking the infection of non-human primates by mucosal challenge with SHIV. Such studies provided a rationale for testing groups of monoclonal antibodies with synergistic neutralizing antibodies in vitro as immediate postexposure prophylaxis, modeling for perinatal exposure in infants. Cocktails of human IgG1b12, 2G12, 2F5, and 4E10 neutralizing monoclonal antibodies prevented disease in newborn macaques and prevented the establishment of SHIV89.6P infection in half of the animals when given within an hour of exposure (Ferrantelli et al., AIDS; 17: 301-309, 2003). Studies in recently infected HIV patients indicated that neutralizing antibodies are indeed involved in controlling viral replication during the first months after infection, and that the pressure they exert on the virus is significant (Richman et al., Proc Natl Acad Sci, USA; 100:4144-4149, 2003).
[0025] Budding of nascent virus also occurs from lipid rafts. Thus, in addition to preventing new infection, the present invention is applicable to preventing the spread of infection or re-infection. Clinical application of antibodies created by this method may also prevent outbreaks of virus in infected individuals (e.g., herpes outbreaks). Beta-cyclodextrins deplete cholesterol and disrupt lipid rafts. A novel use of β-cyclodextrins is extended to applications (e.g., topical cream) to prevent recurrent herpes zoster, herpes oral or genital outbreaks. Topical use of β-cyclodextrins may also reduce the severity of outbreaks as well as shorten their duration. Many pathogens exploit lipid rafts for cell infection as well as cell outbreak. This use of β-cyclodextrins and the disruption of raft structure as a portal for entry or exit are applicable to any pathogen outbreak, which involves lipid rafts. As such, pathogen release from infected cells or neurons may be prevented by the disruption of raft structure by β-cyclodextrins.
[0026] The present invention relates to methods of reducing the risk of virus budding or diminishing the severity of outbreak of viral infections. It also may be used to diminish pain and associated symptoms of post-outbreak neuralgia. In one embodiment, a method of the invention is performed by contacting area of viral release (e.g., dermatomes in shingles) with a β-cyclodextrin (β-CD). The afflicted dermatomes may be identified by a tingling sensation (a prodrome), which signals the onset of viral release. Examples of said releasable viruses include but are not limited to: an enveloped virus, for example, an immunodeficiency virus such as human immunodeficiency virus (HIV); a T lymphotrophic virus such as human T lymphotrophic virus (HTLV); a herpes virus such as a herpes simplex virus (HSV); a measles virus; a chicken pox virus or an influenza virus. The β-CD can be any β-CD derivative, for example, 2-hydroxypropyl-β-cyclodextrin. In the case of herpes zoster or any outbreak resulting in an outbreak-induced neuralgia, the pain and associated symptoms may be amenable to topical treatment of β-CD.
[0027] The present invention also relates to a pharmaceutical composition, which includes β-CD, which is in a sufficient amount to block viral release through lipid rafts in the membrane of a nerve cell.
[0028] The present invention further relates to a composition, comprising a solid substrate that contains an effective amount of β-CD useful for reducing the risk of viral release and the severity of viral outbreak. The pharmaceutical composition can be formulated in a solution, a gel, a foam, an ointment, a cream, a paste, a spray, or the like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 shows a cyclodextrin molecule. Linking D-glucose units together with α-1,4 linkages means that the growth of the polysaccharide follows a helical path. Occasionally, this coiling brings the D-glucose at the end of the growing polymer chain close enough to the one at the beginning that a glycosidic bond can form between them, thereby creating a cyclic polysaccharide. These structures are known as cyclodextrins. FIG. 1 presents the structure of one such compound which contains a ring comprised of eight D-glucose units. This compound is known as γ-cyclodextrin. Cyclodextrins are natural products formed by the action of enzymes called cycloglucosyltransferases, CGTases, on starch. These enzymes are found in a microorganism called Bacillus macerans. Cyclodextrins participate in host-guest interactions, serving as hosts for a variety of small molecules. The number of monomer units in the macrocyclic ring determines the size of the cavity the host makes available to the guest. The ability of cyclodextrins to “encapsulate” small molecules has led to their use as cholesterol depletors and disruptors of lipid rafts in cells and neurons. FIG. 1 depicts the cavity from above.
[0030] FIG. 2 presents a perspective drawing of the 3-dimensional structure of γ-cyclodextrin. The conformation of the glucose units in the cyclodextrin places the hydrophilic hydroxyl groups at the top and bottom of the three dimensional ring and the hydrophobic glycosidic groups on the interior. Note that the polar OH groups project to the exterior of the structure while the hydrogens attached to the glucose units point into the cavity. Thus the interior is comparatively non-polar. These structural features make the polymer water soluble while still able to transport non-polar materials such as cholesterol. When cyclodextrin is applied to cells or neurons cholesterol is depleted from cellular membranes and resides within the interior non-polar cavity. The depletion of cholesterol from cell membranes disrupts lipid rafts and inhibits cell signaling through raft domains.
DETAILED DESCRIPTION OF THE INVENTION
[0031] To isolate detergent resistant membranes (DRMs) from a cell type including but not limited to primary or transformed lymphocytes. Cells are washed in Buffer A (100 mM NaCl, 10 mM KCl, 10 mM EGTA, 10 mM imidazole, pH 6.8), then in TKM buffer (50 mM Tris-HC1, pH 7.4, 25 mM KCl, 5 mM MgCl, and 1 mM EGTA). To reduce proteolysis, the following protease inhibitors are included in Buffer A: 2 mg/ml of leupeptin (Calbiochem Novabiochem Corp., La Jolla, Calif.); 5 mM Pefa-Bloc (Roche Molecular Biochemicals, Indianapolis, Ind.); 1% aproptinin (Sigma); 1% pepstatin A (Roche Molecular Biochemicals); and 100 nM benzamidine (Sigma). DRMs were prepared using a discontinuous sucrose density gradient. DRMs are located at the interface between 5 and 36% sucrose.
[0032] Alternatively, isolation of low-density, Triton X-100-insoluble membrane complexes is easily performed. Briefly, cells were homogenized in 2-morpholinoethanesulfonic acid (MES)-buffered saline containing 1% Triton X-100 (unless otherwise indicated), and sucrose was added to a final concentration of 40%. A 5 to 30% discontinuous sucrose gradient was layered on top of this detergent extract followed by ultracentrifugation [54,000 rpm in a rotor (Beckman Coulter, Fullerton, Calif.)] for 18 to 24 hours at 4° C. in a TL-100 ultracentrifuge (Beckman Coulter). Successive gradient fractions were collected from the top and subjected to SDS-PAGE and Western blot analysis.
[0033] HIV-1 RF viral supernatant from an infected Jurkat cell line can be collected and clarified through a 0.45 μm filter. Virus supernatant (10 ml) can be co-cultured with purified lipid raft fractions as described above. These lipid raft/virus co-cultures serve as immunogens for the creation of novel antibodies. Following hybridoma fusion to create monoclonal expressing immortalized B-cells, antibodies produced in this fashion can be mass screened to determine their effectiveness as neutralizing antibodies. The capacity of purified IgG as well as whole serum, to neutralize HIV can be tested in an assay with phytohemagglutinin-stimulated peripheral blood mononuclear cells. Briefly, antibodies or sera were incubated for 1 h at 37° C. with diluted tissue culture supernatant of virus-infected peripheral blood mononuclear cells (40 to 100 50% tissue culture infective doses, 100 μl). Peripheral blood mononuclear cells (10 5 in 50 μl) were added to the virus-antibody reaction mixture, and the mixture was incubated overnight. All dilutions were performed with RPMI 1640 medium (GIBCO, Life Technologies Ltd., Paisley, Scotland) supplemented with 10% fetal calf serum, 3 mM glutamine, 20 IU of interleukin-2, and antibiotics. Medium changes were performed on days 1 and 4. Seven days after infection, supernatants were collected and analyzed for HIV antigen by a capture ELISA. The neutralization titer was defined as the reciprocal of the last dilution step that showed an 80% or greater reduction in the OD at 490 nm of the culture supernatant compared to that of HIV antibody-negative serum.
[0034] Beta-cyclodextrins β-CDs) are widely used as solubilizing agents, stabilizers, and inert excipients in pharmaceutical compositions (see U.S. Pat. Nos. 6,194,430; 6,194,395; and 6,191,137, each of which is incorporated herein by reference). Beta-CDs are cyclic compounds containing seven units of α-(1,4) linked D-glucopyranose units, and act as complexing agents that can form inclusion complexes and have concomitant solubilizing properties (see U.S. Pat. No. 6,194,395; see also, Szejtli, J. Cyclodextrin Technol. 1988).
[0035] The compositions and methods of the invention are exemplified using 2-hydroxypropyl-β-CD (2-OH-β-CD). However, any β-CD derivative can be used in a composition or method of the invention, provided the β-CD derivative disrupts lipid rafts in the membranes of nerve cells. Beta-CDs act, in part, by removing cholesterol from cell membranes, and different β-CDs are variably effective in such removal. For example, methyl-β-CD removes cholesterol from cell membranes very efficiently and quickly and, as a result, can be toxic to cells, which require cholesterol for membrane integrity and viability. In comparison, a β-CD derivative such as 2-OH-β-CD can effectively remove cholesterol from cells without producing undue toxicity. Thus, it will be recognized that a β-CD useful in a composition or method of the invention is one that removes cholesterol in an amount that disrupts lipid rafts, without substantially reducing cell viability (see, for example, Rothblat and Phillips, J. Biol. Chem. 257:4775-4782 (1982), which is incorporated herein by reference).
[0036] Beta-CDs useful in the present invention include, but are not limited to, β-CD derivatives wherein one or more of the hydroxy groups is substituted by an alkyl, hydroxyalkyl, carboxyalkyl, alkylcarbonyl, carboxyalkoxyalkyl, alkylcarbonyloxyalkyl, alkoxycarbonylalkyl or hydroxy-(mono or polyalkoxy)alkyl group or the like; and wherein each alkyl or alkylene moiety contains up to about six carbons. Substituted β-CDs that can be used in the present invention include, for example, polyethers (see, for example, U.S. Pat. No. 3,459,731, which is incorporated herein by reference); ethers, wherein the hydrogen of one or more β-CD hydroxyl groups is replaced by C 1 to C6 alkyl, hydroxy-C 1-C6-alkyl, carboxy-C 1-C6 alkyl, C 1-C6 alkyloxycarbonyl-C1-C6 alkyl groups, or mixed ethers thereof. In such substituted β-CDs, the hydrogen of one or more β-CD hydroxy group can be replaced by C1-C3 alkyl, hydroxy-C2-C4 alkyl, or carboxy-C1-C2 alkyl, for example, by methyl, ethyl, hydroxyethyl, hydroxypropyl, hydroxybutyl, carboxymethyl or carboxyethyl. It should be recognized that the term “C1-C6 alkyl” includes straight and branched saturated hydrocarbon radicals, having from 1 to 6 carbon atoms. Examples of β-CD ethers include dimethyl-β-CD. Examples of β-CD polyethers include hydroxypropyl-p-β-CD and hydroxyethyl-β-CD (see, for example, Nogradi, “Drugs of the Future” 9(8):577-578, 1984; Chemical and Pharmaceutical Bulletin. 28:1552-1558 (1980); Yakugyo Jiho No. 6452 (Mar. 28, 1983); Angew. Chem. Int. Ed. Engl. 19:344-362 (1980); U.S. Pat. No. 3,459,731; EP-A-0,149,197; EP-A-0,197,571; U.S. Pat. No. 4,535,152; WO-90112035; GB-2,189,245; Szejtli, “Cyclodextrin Technology” (Kluwer Academic Publ. 1988); Bender et al., “Cyclodextrin Chemistry” (Springer-Verlag, Berlin 1978); French, Adv. Carb. Chem. 12:189-260; Croft and Bartsch, Tetrahedron 39:1417-1474, 1983; Irie et al., Pharm. Res. 5:713-716, 1988; Pitha et al., Internat'l. J. Pharm. 29:73, 1986; U.S. Pat. No. 5,134,127 A; U.S. Pat. Nos. 4,659,696 and 4,383,992, each of which is incorporated herein by reference; see, also, U.S. Pat. No. 6,194,395).
[0037] A method of the invention is performed, for example, by contacting an area of skin susceptible to viral release with a β-CD. As used herein, the term “contacting,” when used in reference to a β-CD and the pathogen or cells susceptible to a sexually transmitted pathogen, means that the β-CD is applied to the susceptible area such that it prevents viral budding through lipid rafts at nerve terminals.
[0038] As described above, budding of HIV-1 particles occurs at lipid rafts, which are characterized by a distinct lipid composition that includes high concentrations of cholesterol, sphingolipids, and glycolipids. Since cholesterol plays a key role in the entry of some other viruses, the role in HIV-1 entry of cholesterol and lipid rafts in the plasma membrane of susceptible cells was investigated. Example 2 demonstrates that intact lipid rafts are necessary for viral infection. A β-CD derivative, 2-hydroxypropyl-β-cyclodextrin (2-OH-β-CD), was used to deplete cellular cholesterol and disperse lipid rafts. As disclosed herein, removal of cellular cholesterol rendered primary cells and cell lines highly resistant to HIV-1-mediated syncytium formation and to infection by both CXCR4- and CCR5-specific strains of HIV-1 virus. 2-OH-β-CD treatment of the virus or cells partially reduced HIV-1 binding, while rendering chemokine receptors highly sensitive to antibody-mediated internalization, but had no effect on CD4 expression. These effects were readily reversed by incubating cholesterol-depleted cells with low concentrations of cholesterol-loaded 2-OH-β-CD to restore cholesterol levels. Cholesterol depletion also made cells resistant to SDF-1-induced binding to ICAM-1 through LFA-1. This may have contributed to the reduction in HIV-1 binding to cells after treatment with the β-CD, since LFA-1 contributes significantly to cell binding by HIV-1 which, like SDF-1α, can trigger CXCR4 function through gp120. These results indicate that cholesterol is involved in the HIV-1 co-receptor function of chemokine receptors and is required for infection of cells by HIV-1 (Example 2).
[0039] As discussed above, cholesterol, sphingolipids, and GPI-anchored proteins are enriched in lipid rafts (see Simons and Ikonen, Nature. 387:569-572, 1997). The high concentration of cholesterol and sphingolipids in lipid rafts results in a tightly packed, ordered lipid domain that is resistant to non-ionic detergents at low temperature. The structural protein caveolin causes formation of flask-shaped invaginations (caveolae) in the cell membrane with a lipid composition very similar to that of lipid rafts (Schnitzer et al., Science 269: 1435-1439, 1995). Signaling molecules, including Lck, LAT, NOS, and G protein α subunit, are localized to rafts on the intracellular side of the membrane, and are targeted by lipid modifications such as palmitylation, myristylation, or both. In comparison, many other transmembrane proteins do not show a preference for lipid rafts; for example, CD45 and E cadherin are excluded from these areas. Certain lipid modified transmembrane proteins such as the HA molecule of influenza virus localize to lipid rafts.
[0040] As disclosed herein, HIV-1 buds selectively from lipid rafts of infected T cells (Example 1). In addition, Semliki Forest Virus (SFV), measles viruses, influenza viruses, and polioviruses all assemble by raft association and, in the case of influenza virus, bud from lipid rafts (see, for example, Marquardt et al., J. Cell Biol. 123:57-65, 1993; Manie et al., J. Virol. 74:305-311, 2000; Zhang et al., J. Virol. 74:4634-4644, 2000, each of which is incorporated herein by reference). The involvement of lipid rafts in HIV-1 biology beyond its role in virus budding has been further examined. As further disclosed herein, partial depletion of cholesterol from cell membranes using a β-CD inhibited HIV-1-induced syncytium formation in cell lines and primary T cells (Example 2). β-CD treatment of cells also increased CR internalization induced by monoclonal antibody (MAb) binding. Primary cells and cell lines were rendered resistant to infection CXCR4-specific and CCR5-specific HIV-1 strains by treatment with 2-OH-β-CD (Example 2). The effects observed were not due to loss of cell viability after treatment with the β-CD, and demonstrate that intact lipid rafts and cholesterol are required for HIV-1 infection and syncytium formation.
[0041] The present invention also provides compositions useful for reducing the risk of transmission of sexually transmitted disease. A composition of the invention contains a β-CD, which can be in a form suitable for topical administration to a subject, particularly intravaginal or intrarectal use, including a suppository or a bioadhesive polymer, which can provide timed release of the β-CD (see, for example, U.S. Pat. Nos. 5,958,461 and 5,667,492, each of which is incorporated herein by reference); or can be formulated in combination with a solid substrate to produce a condom, diaphragm, sponge, tampon, a glove or the like (see, for example, U.S. Pat. Nos. 6,182,661 and 6,175,962, each of which is incorporated herein by reference), which can be composed, for example, of an organic polymer such as polyvinyl chloride, latex, polyurethane, polyacrylate, polyester, polyethylene terephthalate, polymethacrylate, silicone rubber, a silicon elastomer, polystyrene, polycarbonate, a polysulfone, or the like (see, for example, U.S. Pat. No. 6,183,764, which is incorporated herein by reference).
[0042] For topical administration, the β-CD can be formulated in any pharmaceutically acceptable carrier, provided that the carrier does not affect the activity of the β-CD in an undesirable manner. Thus, the composition can be, for example, in the form of a cream, a foam, a jelly, a lotion, an ointment, a solution, a spray, or a gel (see U.S. Pat. No. 5,958,461, which is incorporated herein by reference). In addition, the composition can contain one or more additional agents, for example, an antimicrobial agent such as an antibiotic or an antimicrobial dye such as methylene blue or gentian violet (U.S. Pat. No. 6,183,764); an antiviral agent such as a nucleoside analog (e.g., azacytidine), a zinc salt (see U.S. Pat. No. 5,980,477, which is incorporated herein by reference), or a cellulose phthalate such as cellulose acetate phthalate or a hydroxypropyl methylcellulose phthalate (see U.S. Pat. No. 5,985,313, which is incorporated herein by reference); a contraceptive (see U.S. Pat. No. 5,778,886, which is incorporated herein by reference); a lubricant, or any agent generally useful to a sexually active individual, provided the additional agent, either alone or in combination, does not affect the activity of the β-CD or, if it affects the activity of the β-CD, does so in a predictable way such that an amount of β-CD that is effective for reducing viral outbreak can be determined.
[0043] A pharmaceutically acceptable carrier useful in a composition of the invention can be aqueous or non-aqueous, for example alcoholic or oleaginous, or a mixture thereof, and can contain a surfactant, emollient, lubricant, stabilizer, dye, perfume, preservative, acid or base for adjustment of pH, a solvent, emulsifier, gelling agent, moisturizer, stabilizer, wetting agent, time release agent, humectant, or other component commonly included in a particular form of pharmaceutical composition. Pharmaceutically acceptable carriers are well known in the art and include, for example, aqueous solutions such as water or physiologically buffered saline or other solvents or vehicles such as glycols, glycerol, oils such as olive oil or injectable organic esters. A pharmaceutically acceptable carrier can contain physiologically acceptable compounds that act, for example, to stabilize or to increase the absorption of the β-CD, for example, carbohydrates, such as glucose, sucrose or dextrans, antioxidants, such as ascorbic acid or glutathione, chelating agents, low molecular weight proteins or other stabilizers or excipients.
[0044] The pharmaceutical composition also can comprise an admixture with an organic or inorganic carrier or excipient suitable for intravaginal or intrarectal administration, and can be compounded, for example, with the usual non-toxic, pharmaceutically acceptable carriers for tablets, pellets, capsules, suppositories, solutions, emulsions, suspensions, or other form suitable for use. The carriers, in addition to those disclosed above, can include glucose, lactose, mannose, gum acacia, gelatin, mannitol, starch paste, magnesium trisilicate, talc, corn starch, keratin, colloidal silica, potato starch, urea, medium chain length triglycerides, dextrans, and other carriers suitable for use in manufacturing preparations, in solid, semisolid, or liquid form. In addition auxiliary, stabilizing, thickening or coloring agents and perfumes can be used, for example a stabilizing dry agent such as triulose (see, for example, U.S. Pat. No. 5,314,695).
[0045] The β-CD also can be incorporated within an encapsulating material such as into an oil-in-water emulsion, a microemulsion, micelle, mixed micelle, liposome, microsphere or other polymer matrix (see, for example, Gregoriadis, Liposome Technology, Vol. 1 (CRC Press, Boca Raton, Fla. 1984); Fraley, et al., Trends Biochem. Sci., 6:77 (1981), each of which is incorporated herein by reference). Liposomes, for example, which consist of phospholipids or other lipids, are nontoxic, physiologically acceptable and metabolizable carriers that are relatively simple to make and administer. “Stealth” liposomes (see U.S. Pat. Nos. 5,882,679; 5,395,619; and 5,225,212, each of which is incorporated herein by reference) are an example of such encapsulating materials particularly useful for preparing a pharmaceutical composition of the invention, and other “masked” liposomes similarly can be used, such liposomes extending the time that the β-CD remains at the site of administration.
[0046] The amount a β-CD in a composition can be varied, depending on the type of composition, such that the amount present is sufficient to reduce viral outbreak or reduce severity of outbreak. An example of such an amount is about 1 to 100 mM, generally about 5 to 30 mM, when administered in an ointment, gel, foam, spray or the like, or about 0.1 to 2 grams, generally about 0.25 to 0.75 grams, when administered as a suppository or in combination with a solid substrate. An effective amount of a β-CD also can be measured in a weight:weight (w:w) or weight:volume (w:v) amount, for example, about 0.1% to 3% w:w with respect to a solid substrate or about 0.1% to 3% w:v with respect to a pharmaceutically acceptable carrier. In addition, an amount of a β-CD sufficient to reduce viral outbreak or decrease outbreak severity can be determined using routine clinical methods, including Phase I, II and III clinical trials.
[0047] Currently, several HIV-1 vaccine approaches are being developed, each with its own relative strengths and weaknesses. These approaches include the development of live attenuated vaccines, inactivated viruses with adjuvant peptides and subunit vaccines, live vector-based vaccines, and DNA vaccines. Envelope glycoproteins were considered as the prime antigen in the vaccine regimen due to their surface-exposure, until it became evident that they are not ideal immunogens. This is an expected consequence of the immunological selective forces that drive the evolution of these viruses: it appears that the same features of envelope glycoproteins that dictate poor immunogenicity in natural infections have hampered vaccine development. However, modification of the vaccine recipe through the use of raft/virus co-cultures to expose novel viral epitopes may overcome these problems.
[0048] Accordingly, there is a need in the art for new effective methods of identifying candidate sequences for vaccine development to prevent and treat HIV infection. The present invention fulfills this and other needs.
[0049] “Antibody” refers to a polypeptide substantially encoded by an immunoglobulin gene or immunoglobulin genes, or fragments thereof, that specifically bind and recognize an analyte (antigen). The recognized immunoglobulin genes include the kappa, lambda, alpha, gamma, delta, epsilon and mu constant region genes, as well as the myriad immunoglobulin variable region genes. Light chains are classified as either kappa or lambda. Heavy chains are classified as gamma, mu, alpha, delta, or epsilon, which in turn define the immunoglobulin classes, IgG, IgM, IgA, IgD and IgE, respectively.
[0050] An exemplary immunoglobulin (antibody) structural unit comprises a tetramer. Each tetramer is composed of two identical pairs of polypeptide chains, each pair having one “light” (about 25 kDa) and one “heavy” chain (about 50-70 kDa). The N-terminus of each chain has a variable region of about 100 to 110 or more amino acids primarily responsible for antigen recognition. The terms variable light chain (VL) and variable heavy chain (VH) refer to these light and heavy chains, respectively.
[0051] Antibodies exist, for example, as intact immunoglobulins or as a number of well characterized antigen-binding fragments produced by digestion with various peptidases. For example, pepsin digests an antibody below the disulfide linkages in the hinge region to produce an F(ab′) 2 fragment, a dimer of Lab which itself is a light chain joined to VH-CH1 by a disulfide bond. The F(ab′) 2 fragment can be reduced under mild conditions to break the disulfide linkage in the hinge region, thereby converting the F(ab′) 2 dimer into an Fab′ monomer. The Fab′ monomer is essentially an Fab with part of the hinge region (see, Fundamental Immunology, Third Edition, W. E. Paul (ed.), Raven Press, N.Y. (1993)). While various antibody fragments are defined in terms of the digestion of an intact antibody, one of skill will appreciate that such fragments can be synthesized de novo either chemically or by utilizing recombinant DNA methodology. Thus, the term antibody, as used herein, also includes antibody fragments, such as a single chain antibody, an antigen binding F(ab′) 2 fragment, an antigen binding Fab′ fragment, an antigen binding Fab fragment, an antigen binding Fv fragment, a single heavy chain or a chimeric antibody. Such antibodies can be produced by the modification of whole antibodies or synthesized de novo using recombinant DNA methodologies.
[0052] Thus, an immunogenic composition to this subtype B ancestor protein will elicit broad neutralizing antibody against HIV-1 isolates of the same subtype. An immunogenic composition to this subtype B ancestor protein will also elicit a broad cellular response mediated by antigen-specific T-cells.
[0053] Monoclonal antibodies (MAbs) have been available for over 25 years and have revolutionized biomedical research, especially in the areas of disease diagnosis and the treatment of infection and diseases.
[0054] The conventional method for the production of monoclonal antibodies involves hybridomas (Kohler & Milstein, Nature 256:495-7, 1975). In this method, splenic or lymphocyte cells from a mammal which has been injected with antigen are fused with a tumor cell line, thus producing hybrid cells. These hybrid cells, or “hybridomas”, are both immortal and capable of producing the genetically coded antibody of a B cell. To select a hybridoma producing a single antibody, the hybridomas made by cell fusion are segregated by selection, dilution, and regrowth until a single genetically pure antibody-expressing cell line is selected. Because hybridomas produce homogeneous antibodies against a desired antigen, they are called “monoclonal” antibodies. Hybridoma technology has primarily been focused on the fusion of murine lines, but also human-human hybridomas, human-murine hybridomas, rabbit-rabbit hybridomas and other xenogenic hybrid combinations have been made.
EXAMPLES
Example 1
[0055] HIV-1 Selectively Buds from Lipid Rafts
[0056] This example demonstrates that HIV-1 budding occurs through lipid rafts, thereby accounting for the cholesterol-rich, sphingolipid-rich virus membrane, which bears GPI-linked proteins such as Thy-1 and CD59, but lacks CD45.
[0057] The relative incorporation of GM1, a ganglioside marker specific for lipid rafts, also was examined. Using a soluble CTB binding assay, as much as 75% of HIV-1 was precipitated using goat anti-CTB and SaC after treating the virus with GM1-specific CTB. The CTB binding to virus was specific and dose dependent, and no virus was precipitated in the absence of CTB as measured by p24 ELISA. These results demonstrate that the majority of HIV-1 particles incorporate the lipid raft-specific marker GM1.
[0058] Thy-1, CD59, and GM1 colocalized with HIV-1 proteins on infected cell uropods, which excluded CD45. To determine the distribution of HIV-1 proteins relative to GPI-linked proteins that serve as lipid raft markers, infected cells were subjected to immunofluorescence staining followed by confocal microscopy. Expression of HIV-1 proteins was localized to uropods projecting from one end of the cell. This capping pattern was seen on most cells in the infected cell culture. Uropods protruding from HIV-1-infected cells have been described for adherent T cells. Thy-1 and CD59 both colocalized with cell surface HIV-1 proteins, as shown by a superimposed green (Thy-1 or CD59) and red (HIV-1 proteins) fluorescence (see Nguyen and Hildreth, supra, 2000; FIG. 4 ). Cells that were prefixed with 2% paraformaldehyde before staining showed a similar appearance, indicating that the colocalization was not due to antibody crosslinking of viral and GPI-linked proteins. Since the cells were not permeabilized before staining, the HIV proteins seen in these studies are likely gp41 and gp120. This was confirmed in studies with anti-gp41 MAb T32 in the colocalization studies. Uninfected cells showed no capping of Thy-1 or CD59. CD45 did not localize to areas of HIV-1 protein expression and was excluded from uropods. The distribution of CD45 was unaffected by HIV-1 infection, and the molecule remained evenly dispersed in patches all over the cell surface. These results confirm those obtained using the virus phenotyping studies. The ability of GM1 to colocalize on the cell surface with HIV-1 proteins was examined to confirm the finding that GM1 was present on virions. GM1 staining was relatively faint with rabbit anti-GM1 antibody, but confocal microscopy showed colocalization of this molecule with HIV-1 labeled cells.
[0059] HIV-1 proteins were detected in isolated lipid raft fractions. Lipid rafts were purified by cell lysis and equilibrium centrifugation in order to confirm the presence of HIV-1 proteins in these membrane structures. The fractions were assayed for the presence of viral and host proteins by immunoblot analysis. The separation of detergent-resistant lipid rafts was confirmed by the abundance of Thy-1 and CD59 in fractions 3 through 5, while CD45 was present only in the bottom fractions 9 and 10 (see Nguyen and Hildreth, supra, 2000; FIG. 6 ). Immunoblot detection of membrane fractions revealed that the HIV MA protein, p17, and gp41 were both present in the detergent-insoluble lipid rafts of infected cells.
Example 2
[0060] Host Membrane Cholesterol is Required for HIV-1 Infection
[0061] By removing cholesterol, 2-OH-β-CD is believed to partially perturb organized lipid rafts, resulting in dispersal of their components (Ilangumaran and Hoessli, Biochem. J. 335:433-440, 1998). The capture of HIV-1 by MAbs against CD59 and gp41 decreased substantially after treating cells with 2-OH-β-CD, as measured by the percentage of total p24. CD45 capture remained unaffected. The effects on virus precipitation through gp41 indicate that intact lipid rafts are required for efficient gp41 incorporation into virions, since the overall cellular release of p24 actually increased after 2-OH-β-CD treatment.
[0062] Results. 2-OH-β-CD treatment blocked syncytium formation of primary cells and cell lines. The role of lipid rafts in the HIV-1 fusion process was examined by treating CD4+ HIV-susceptible target cells with 2-OH-β-CD to deplete membrane cholesterol and disperse lipid rafts. Treatment of cells with 10 to 20 mM 2-OH-β-CD for 1 hour at 37° C., followed by washing to remove free 2-OH-β-CD, depleted greater than 70% of total cellular cholesterol without any loss in cell viability as measured by Trypan Blue exclusion. Furthermore, treated cells continued to grow normally after 2-OH-β-CD treatment when placed back into culture in cholesterol-containing medium. The non-toxicity of β-CD treatment was further demonstrated by finding 2-OH-β-CD treated Jurkat cells still showed Ca 2+ flux responses to anti-CD3 MAb. | Disclosed is a novel application for β-cyclodextrin (β-CD, a cholesterol depletor), and a novel technique for the creation of immunogens. Topical application of β-CD inhibits or reduces the severity of viral outbreaks such as oral or genital herpes by disrupting lipid rafts, through which viral entry and outbreak occur. Viral entry involves virus/lipid raft interaction, wherein the virus unfolds—only in lipid rafts—to enter the cell via the lipid raft. The invention provides a technique for creating immunogens with novel viral epitopes based on the virus/lipid raft interaction and viral unfolding. This fact can be exploited to create novel immunogens based on viral interaction with lipid rafts. The virus/lipid raft co-culture technique creates novel immunogens which will be used to create novel neutralizing monoclonal and polyclonal antibodies to fight viral disease such as HIV infection. | 0 |
CROSS-REFERENCE
[0001] This application claims priority to U.S. application Ser. No. 14/273,522, filed May 8, 2014 entitled “METHOD AND APPARATUS FOR RAPID SCALABLE UNIFIED INFRASTRUCTURE SYSTEM MANAGEMENT PLATFORM”, which claims the benefit of Provisional Patent Application Nos. 61/820,703 filed May 8, 2013 entitled “METHOD AND APPARATUS TO REMOTELY MONITOR INFORMATION TECHNOLOGY INFRASTRUCTURE”; 61/820,704 filed May 8, 2013 entitled “METHOD AND APPARATUS TO ORCHESTRATE ANY-VENDOR IT INFRASTRUCTURE (COMPUTE) CONFIGURATION”; 61/820,705 filed May 8, 2013 entitled “METHOD AND APPARATUS TO ORCHESTRATE ANY-VENDOR IT INFRASTRUCTURE (NETWORK) CONFIGURATION”; 61/820,706 filed May 8, 2013 entitled “METHOD AND APPARATUS TO ORCHESTRATE ANY-VENDOR IT INFRASTRUCTURE (STORAGE) CONFIGURATION”; 61/820,707 filed May 8, 2013 entitled “METHOD AND APPARATUS TO ENABLE LIQUID APPLICATIONS”; 61/820,708 filed May 8, 2013 entitled “METHOD AND APPARATUS TO ENABLE LIQUID APPLICATIONS”; 61/820,709 filed May 8, 2013 entitled “METHOD AND APPARATUS TO ENABLE CONVERGED INFRASTRUCTURE TRUE ELASTIC FUNCTION”; 61/820,712 filed May 8, 2013 entitled “METHOD AND APPARATUS FOR OPERATIONS BIG DATA ANALYSIS AND REAL TIME REPORTING”; and 61/820,713 filed May 8, 2013 entitled “METHOD AND APPARATUS FOR RAPID SCALABLE UNIFIED INFRASTRUCTURE SYSTEM MANAGEMENT PLATFORM”; 61/827,635 filed May 26, 2013 entitled “METHOD AND APPARATUS FOR REMOTELY MANAGEABLE, DECLARATIVELY CONFIGURABLE DATA STREAM AGGREGATOR WITH GUARANTEED DELIVERY FOR PRIVATE CLOUD COMPUTE INFRASTRUCTURE”, and this application also claims the benefit of U.S. Provisional Patent Application No. 61/827,636 filed May 26, 2013 entitled “METHOD AND APPARATUS FOR REMOTELY MANAGEABLE, DECLARATIVELY CONFIGURABLE DATA STREAM AGGREGATOR WITH GUARANTEED DELIVERY FOR PRIVATE CLOUD COMPUTE INFRASTRUCTURE”, the contents of which are all herein incorporated by reference in its entirety.
FIELD
[0002] The disclosure generally relates to enterprise cloud computing and more specifically to a seamless cloud across multiple clouds providing enterprises with quickly scalable, secure, multi-tenant automation.
BACKGROUND
[0003] Cloud computing is a model for enabling on-demand network access to a shared pool of configurable computing resources/service groups (e.g., networks, servers, storage, applications, and services) that can ideally be provisioned and released with minimal management effort or service provider interaction.
[0004] Software as a Service (SaaS) provides the user with the capability to use a service provider's applications running on a cloud infrastructure. The applications are accessible from various client devices through either a thin client interface, such as a web browser or a program interface. The user does not manage or control the underlying cloud infrastructure including network, servers, operating systems, storage, or even individual application capabilities.
[0005] Infrastructure as a Service (IaaS) provides the user with the capability to provision processing, storage, networks, and other fundamental computing resources where the user is able to deploy and run arbitrary software, which can include operating systems and applications. The user does not manage or control the underlying cloud infrastructure but has control over operating systems, storage, and deployed applications; and possibly limited control of select networking components (e.g., host firewalls).
[0006] Platform as a Service (PaaS) provides the user with the capability to deploy onto the cloud infrastructure user-created or acquired applications created using programming languages, libraries, services, and tools supported by the provider. The user does not manage or control the underlying cloud infrastructure including network, servers, operating systems, or storage, but has control over the deployed applications and possibly configuration settings for the application-hosting environment.
[0007] Cloud deployment may be Public, Private or Hybrid. A Public Cloud infrastructure is provisioned for open use by the general public. It may be owned, managed, and operated by a business, academic, or government organization. It exists on the premises of the cloud provider. A Private Cloud infrastructure is provisioned for exclusive use by a single organization comprising multiple users (e.g., business units). It may be owned, managed, and operated by the organization, a third party, or some combination of them, and it may exist on or off premises. A Hybrid Cloud infrastructure is provisioned for exclusive use by a single organization comprising multiple users (e.g., business units). It may be owned, managed, and operated by the organization, a third party, or some combination of them, and it may exist on or off premises.
[0008] The promise of enterprise cloud computing was supposed to lower capital and operating costs and increase flexibility for the Information Technology (IT) department. However lengthy delays, cost overruns, security concerns, and loss of budget control have plagued the IT department. Enterprise users must juggle multiple cloud setups and configurations, along with aligning public and private clouds to work together seamlessly. Turning up of cloud capacity (cloud stacks) can take months and many engineering hours to construct and maintain. High-dollar professional services are driving up the total cost of ownership dramatically. The current marketplace includes different ways of private cloud build-outs. Some build internally hosted private clouds while others emphasize Software-Defined Networking (SDN) controllers that relegate switches and routers to mere plumbing.
[0009] The cloud automation market breaks down into several types of vendors, ranging from IT operations management (ITOM) providers, limited by their complexity, to so-called fabric-based infrastructure vendors that lack breadth and depth in IT operations and service. To date, true value in enterprise cloud has remained elusive, just out of reach for most organizations. No vendor provides a complete Cloud Management Platform (CMP) solution.
[0010] Therefore there is a need for systems and methods that create a unified fabric on top of multiple clouds reducing costs and providing limitless agility.
SUMMARY OF THE INVENTION
[0011] Additional features and advantages of the disclosure will be set forth in the description which follows, and will become apparent from the description, or can be learned by practice of the herein disclosed principles by those skilled in the art. The features and advantages of the disclosure can be realized and obtained by means of the disclosed instrumentalities and combinations as set forth in detail herein. These and other features of the disclosure will become more fully apparent from the following description, or can be learned by the practice of the principles set forth herein.
[0012] A Cloud Management Platform is described for fully unified compute and virtualized software-based networking components empowering enterprises with quickly scalable, secure, multi-tenant automation across clouds of any type, for clients from any segment, across geographically dispersed data centers.
[0013] In one embodiment, systems and methods are described for sampling of data center devices alerts; selecting an appropriate response for the event; monitoring the end node for repeat activity; and monitoring remotely.
[0014] In another embodiment, systems and methods are described for discovery of compute nodes; assessment of type, capability, VLAN, security, virtualization configuration of the discovered compute nodes; configuration of nodes covering add, delete, modify, scale; and rapid roll out of nodes across data centers.
[0015] In another embodiment, systems and methods are described for discovery of network components including routers, switches, server load balancers, firewalls; assessment of type, capability, VLAN, security, access lists, policies, virtualization configuration of the discovered network components; configuration of components covering add, delete, modify, scale; and rapid roll out of network atomic units and components across data centers.
[0016] In another embodiment, systems and methods are described for discovery of storage components including storage arrays, disks, SAN switches, NAS devices; assessment of type, capability, VLAN, VSAN, security, access lists, policies, virtualization configuration of the discovered storage components; configuration of components covering add, delete, modify, scale; and rapid roll out of storage atomic units and components across data centers.
[0017] In another embodiment, systems and methods are described for discovery of workload and application components within data centers; assessment of type, capability, IP, TCP, bandwidth usage, threads, security, access lists, policies, virtualization configuration of the discovered application components; real time monitoring of the application components across data centers public or private; and capacity analysis and intelligence to adjust underlying infrastructure thus enabling liquid applications.
[0018] In another embodiment, systems and methods are described for analysis of capacity of workload and application components across public and private data centers and clouds; assessment of available infrastructure components across the data centers and clouds; real time roll out and orchestration of application components across data centers public or private; and rapid configurations of all needed infrastructure components.
[0019] In another embodiment, systems and methods are described for analysis of capacity of workload and application components across public and private data centers and clouds; assessment of available infrastructure components across the data centers and clouds; comparison of capacity with availability; real time roll out and orchestration of application components across data centers public or private within allowed threshold bringing about true elastic behavior; and rapid configurations of all needed infrastructure components.
[0020] In another embodiment, systems and methods are described for analysis of all remote monitored data from diverse public and private data centers associated with a particular user; assessment of the analysis and linking it to the user applications; alerting user with one line message for high priority events; and additional business metrics and return on investment addition in the user configured parameters of the analytics.
[0021] In another embodiment, systems and methods are described for discovery of compute nodes, network components across data centers, both public and private for a user; assessment of type, capability, VLAN, security, virtualization configuration of the discovered unified infrastructure nodes and components; configuration of nodes and components covering add, delete, modify, scale; and rapid roll out of nodes and components across data centers both public and private.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to describe the manner in which the above-recited and other advantages and features of the disclosure can be obtained, a more particular description of the principles briefly described above will be rendered by reference to specific embodiments thereof, which are illustrated in the appended drawings. Understanding that these drawings depict only exemplary embodiments of the disclosure and are not therefore to be considered to be limiting of its scope, the principles herein are described and explained with additional specificity and detail through the use of the accompanying drawings in which:
[0023] FIG. 1 is a block diagram of an exemplary hardware configuration in accordance with the principles of the present invention;
[0024] FIG. 2 is a block diagram describing a tenancy configuration wherein the Enterprise hosts systems and methods within its own data center in accordance with the principles of the present invention;
[0025] FIG. 3 is a block diagram describing a super tenancy configuration wherein the Enterprise uses systems and methods hosted in a cloud computing service in accordance with the principles of the present invention;
[0026] FIG. 4 is a logical diagram of the Enterprise depicted in FIG. 1 in accordance with the principles of the present invention;
[0027] FIG. 5 illustrates a logical view that an Enterprise administrator and Enterprise user have of the uCloud Platform depicted in FIG. 1 in accordance with the principles of the present invention;
[0028] FIG. 6 illustrates a flow diagram of a service catalog classifying data center resources into service groups; selecting a service group and assigning it to end users;
[0029] FIG. 7 illustrates a flow diagram of mapping service group categories to user groups that have been given access to a given service group, in accordance with the principles of the present invention;
[0030] FIG. 8 illustrates the Cloud administration process utilizing the tenant cloud instance manager as well as the manager of manager and the ability of uCloud platform to logically restrict and widen scope of Cloud Administration, as well as monitoring;
[0031] FIG. 9 illustrates a hierarchy diagram of the Cloud administration process utilizing the tenant cloud instance manager as well as the manager of manager and the ability of uCloud platform to logically restrict and widen scope of Cloud Administration in accordance with the principles of the present invention;
[0032] FIG. 10 illustrates the logical flow of information from the uCloud Platform depicted in FIG. 1 to a Controller Node in a given Enterprise for compute nodes;
[0033] FIG. 11 illustrates the logical flow of information from the uCloud Platform depicted in FIG. 1 to the Controller Node in a given Enterprise for network components;
[0034] FIG. 12 illustrates the logical flow of information from the uCloud Platform to the Controller Node in a given Enterprise for storage devices;
[0035] FIG. 13 illustrates the application-monitoring component of the uCloud Platform in accordance with the principles of the present invention;
[0036] FIG. 14 illustrates the application-orchestration component of the uCloud Platform in accordance with the principles of the present invention;
[0037] FIG. 15 illustrates the integration of the application-orchestration and application-monitoring components of the uCloud Platform in accordance with the principles of the present invention;
[0038] FIG. 16 illustrates the big data component of the uCloud Platform depicted in FIG. 1 and the relationship to the monitoring component of the platform
[0039] FIG. 17 illustrates the process of deploying uCloud within an Enterprise environment;
[0040] FIG. 18 illustrates a flow diagram in accordance with the principles of the present invention;
[0041] FIG. 19 illustrates a flow diagram in accordance with the principles of the present invention;
[0042] FIG. 20 illustrates a flow diagram in accordance with the principles of the present invention;
[0043] FIG. 21 illustrates a flow diagram in accordance with the principles of the present invention;
[0044] FIG. 22 illustrates a block diagram in accordance with the principles of the present invention;
[0045] FIG. 23 illustrates a block diagram in accordance with the principles of the present invention; and
[0046] FIG. 24 illustrates a block diagram in accordance with the principles of the present invention;
[0047] FIG. 25 illustrates a block diagram in accordance with the principles of the present invention; and
[0048] FIG. 26 illustrates a block diagram in accordance with the principles of the present invention.
DETAILED DESCRIPTION
[0049] The FIGURES and text below, and the various embodiments used to describe the principles of the present invention are by way of illustration only and are not to be construed in any way to limit the scope of the invention. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims. A Person Having Ordinary Skill in the Art (PHOSITA) will readily recognize that the principles of the present invention maybe implemented in any type of suitably arranged device or system. Specifically, while the present invention is described with respect to use in cloud computing services and Enterprise hosting, a PHOSITA will readily recognize other types of networks and other applications without departing from the scope of the present invention.
[0050] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by a PHOSITA to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, a limited number of the exemplary methods and materials are described herein.
[0051] All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates, which may need to be independently confirmed.
[0052] Reference is now made to FIG. 1 that depicts a block diagram of an exemplary hardware configuration in accordance with the principles of the present invention. A uCloud Platform 100 combining self-service cloud orchestration with a Layer 2- and Layer 3-capable encrypted virtual network may be hosted by a cloud computing service such as but not limited to, Amazon Web Services or directly by an enterprise such as but not limited to, a service provider (e.g. Verizon or AT&T), provides a web interface 104 with a Virtual IP (VIP) address, a Rest API interface 106 with a Virtual IP (VIP), a RPM Repository Download Server and, a message bus 110 , and a vAppliance Download Manager 112 . Connections to and from web interface 104 , Rest API interface 106 , RPM Repository Download Server, message bus 110 , and vAppliance Download Manager 112 are preferably SSL secured. Interfaces 104 , 106 , 107 and 109 are preferably VeriSign certificate based with Extra Validation (EV), allowing for 128-bit encryption and third party validation for all communication on the interfaces. In addition to SSL encryption on Message BUS 110 , each message sent across on interface 107 to a Tenant environment is preferably encrypted with a Public/Private key pair thus allowing for extra security per Enterprise/Service Provider communication. The Public/Private key pair security per Tenant prevents accidental information leakage to be shared across other Tenants. Interfaces 108 and 110 are preferably SSL based (with self-signed) certificates with 128-bit encryption. In addition to communication interfaces, all Tenant passwords and Credit Card information stored are preferably encrypted.
[0053] Controller node 121 performs dispatched control, monitoring control and Xen Control. Dispatched control entails executing, or terminating, instructions received from the uCLoud Platform 100 . Xen control is the process of translating instructions received from uCLoud Platform 100 into a Xen Hypervisor API. Monitoring is performed by the monitor controller by periodically gathering management plane information data in an extended platform for memory, CPU, network, and storage utilizations. This information is gathered and then sent to the management plane. The extended platform comprises vAppliance instances that allow instantiation of Software Defined clouds. The management, control, and data planes in the tenant environment are contained within the extended platform. RPM Repository Download Server 108 downloads RPMs (packages of files that contain a programmatic installation guide for the resources contained) when initiated by Control node 121 . The message bus VIP 110 couples between the Enterprise 101 and the uCloud Platform 100 . A Software Defined Cloud (SDC) may comprise a plurality of Virtual Machines (vAppliances) such as, but not limited to a Bridge Router (BR-RTR, Router, Firewall, and DHCP-DNS (DDNS) across multiple virtual local area networks (VLANs) and potentially across data centers for scale, coupled through Compute node (C-N) nodes (aka servers) 120 a - 120 n . The SDC represents a logical linking of select compute nodes (aka servers) within the enterprise cloud. Virtual Networks running on Software Defined Routers 122 and Demilitarized Zone (DMZ) Firewalls are referred to as vAppliances. All Software defined networking components are dynamic and automated, provisioned as needed by the business policies defined in the Service Catalogue by the Tenant Administrator.
[0054] The uCloud Platform 100 supports policy-based placement of vAppliances and compute nodes ( 120 a - 120 n ). The policies permit the Tenant Administrator to do auto or static placement thus facilitating creation of dedicated hardware environment Nodes for Tenant's Virtual Machine networking deployment base.
[0055] The uCloud Platform 100 created SDC environment enables the Tenant Administrator to create lines of businesses or in other words, department groups with segregated networked space and service offerings. This facilitates Tenant departments like IT, Finance and development to all share the same SDC space but at the same time be isolated by networking and service offerings.
[0056] The uCloud Platform 100 supports deploying SDC vAppliances in redundant pair topologies. This allows for key virtual networking building block host nodes to be swapped out and new functional host nodes be inserted managed through uCloud Platform 100 . SDCs can be dedicated to data centers, thus two unique SDCs in different data centers can provide the Enterprise a disaster recovery scenario.
[0057] SDC vAppliances are used for the logical configuration of SDC's within a tenants private cloud. A Router Node is a physical server, or node, in an tenant's private cloud that may be used to host certain vAppliances relating SDC networking. Such vAppliances may include the Router, DDNS, and BR-RTR (Bridge Router) vApplications that may be used to route internet traffic to and from an SDC, as well as establish logical boundaries for SDC accessibility. Two Router Nodes exist, an active Node (-A) and a standby Node (-S), used in the event that the active node experiences failure. The Firewall Nodes, also present in an active and standby pair, are used to filter internet traffic coming into an SDC. There is a singular vAppliance that uses the Firewall Node, that being the Firewall vAppliance. The vAppliances are configured through use of vAppliance templates, which are downloaded and stored by the tenant in the appliance store/Template store.
[0058] Reference is now made to FIG. 2 depicting a block diagram describing a tenancy configuration wherein the Enterprise hosts systems and methods within its own data center in accordance with the principles of the present invention. The uCloud platform 100 is hosted directly on an enterprise 200 which may be a Service Provider such as, but not limited to, Verizon FIOS or AT&T uVerse, which serves tenants A-n 202 , 204 and 206 , respectively. Alternatively, enterprise 200 may be an enterprise having subsidiaries or departments 202 , 204 and 206 that it chooses to keep segregated.
[0059] Reference is now made to FIG. 3 depicting a block diagram of a super tenancy configuration wherein the Enterprise uses systems and methods hosted in a cloud computing service 300 in accordance with the principles of the present invention. In this configuration, the uCloud platform is hosted by a cloud computing service 300 that services Enterprises 302 , 304 and 306 . It should be understood that more or less Enterprises could be serviced without departing from the scope of the invention. In the present example, Enterprise C 306 has sub tenants. Enterprise C 306 may be a service provider (e.g. Verizon FIOS or AT&T u-Verse) or an Enterprise having subsidiaries or departments that it chooses to keep segregated.
[0060] Reference is now made to FIG. 4 depicting a block diagram describing permutations of a Software Defined Cloud (SDC) in accordance with the principles of the present invention. The SDC can be of three types namely Routed 400 , Public Routed 402 and Public 404 . Routed and Routed Public SDC types 400 and 402 respectively are designed to be reachable through the Enterprise IP address space, with the caveat that the Enterprise IP address space cannot be in the same collision domain as these types of SDC IP network space. Furthermore, Routed and Public Routed SDC 400 and 402 respectively can re-use same IP network space without colliding with each other. The Public SDC 404 is Internet 406 facing only, it can have overlapping collision IP space with the Enterprise network. Public SDC 404 further provides Internet facing access only. SDC IP schema is automatically managed by the uCloud platform 100 and does not require Tenant Administrator intervention.
[0061] SDC Software Defined Firewalls 408 are of two/one type, Internet gateway (for DMZ use). The SDC vAppliances (e.g. Firewall 408 , Router 410 ) and compute nodes ( 120 a - 120 n ) provide a scalable Cloud deployment environment for the Enterprise. The scalability is achieved through round robin and dedicated hypervisor host nodes. The host pool provisioning management is performed through uCloud Platform 100 . The uCloud Platform 100 manages dedicated nodes for the compute nodes ( 120 a - 120 n ), it allows for fault isolation across the Tenant's Virtual Machine workload deployment base.
[0062] Referring back to FIG. 1 , an uCloud Platform administrator 102 A, an Enterprise administrator 102 B, and an Enterprise User 102 C without administrator privileges are depicted. To deploy uCloud platform 100 , Enterprise administrator 102 B grants uCloud Platform administrator 102 A information regarding the enterprise environment 101 and the hardware residing within it (e.g. compute nodes 120 a - n ). After this information is supplied, platform 100 creates a customized package that contains a Controller Node 121 designed for the Enterprise 101 . Enterprise administrator 102 B downloads and install Controller Node 121 into the Enterprise environment 101 . The uCloud Platform 100 then generates a series of tasks, and communicates these tasks indirectly with Controller Node 121 , via the internet 111 . The communication is preferably done indirectly so as to eliminate any potential for unauthorized access to the Enterprise's information. The process preferably requires uCloud platform 100 to leave the tasks in an online location, and the tasks are only accessible to the unique Controller Node 121 present in an Enterprise Environment 101 . Controller Node 121 then fulfills the tasks generated by uCloud platform 100 , and thus configures the compute 122 , network 123 , and storage 120 a - n capability of the Enterprise environment 101 .
[0063] Upon completion of the hardware configuration, uCloud platform 100 is deployed in the Enterprise environment 101 . The uCloud platform 100 monitors the Enterprise environment 101 and preferably communicates with Controller Node 121 indirectly. Enterprise administrator 102 B and Enterprise User 102 C use the online portal to access uCloud platform 100 and to operate their private cloud.
[0064] Software defined clouds (SDCs) are created within the uCloud platform 100 configured Enterprise 101 . Each SDC contains compute nodes that are logically linked to each other, as well as certain network and storage components (logical and physical) that create logical isolation for those compute nodes within the SDC. As discussed above, an enterprise 101 may create three types of SDC's: Routed 400 , Public Routed 402 , and Public 404 as depicted in FIG. 4 . The difference, as illustrated by FIG. 4 , is how each SDC is accessible to an Enterprise user 102 C.
[0065] Reference is now made to FIG. 5 that depicts a logical view of the uCloud Platform 100 that the Enterprise administrator 102 B and Enterprise user 102 C have in accordance with the principles of the present invention. Resources compute 502 , network 504 and storage 506 residing in a data center 507 are coupled to the service catalog 508 that classifies the resources into service groups 510 a - 510 n . A monitor 512 is coupled to the service catalog 508 and to a user 514 . User 514 is also coupled to service catalog 508 . Service catalog 508 is configured to designate various data center items (compute 502 , network 504 , and storage 506 ) as belonging to certain service groups 510 a - 510 n . The Service catalog 508 also maps the service groups to the appropriate User. Additionally, monitor 512 monitors and controls the service groups belonging to a specific User.
[0066] The service catalog 508 allows for a) the creation of User defined services: a service is a virtual application, or a category/group of virtual applications to be consumed by the Users or their environment, b) the creation of categories, c) the association of virtual appliances to categories, d) the entitlement of services to tenant administrator-defined User groups, and e) the Launch of services by Users through an app orchestrator. The service catalog 508 may then create service groups 510 a - 510 n . A service group is a classification of certain data center components e.g. compute Nodes, network Nodes, and storage Nodes.
[0067] Monitoring in FIG. 5 is done by periodically gathering management plane information data in the extended platform for memory, CPU, network, storage utilizations. This information is gathered and then sent to the management plane.
[0068] FIG. 6 illustrates a flow diagram of a service catalog classifying data center resources into service groups; selecting a service group and assigning it to end users. FIG. 7 illustrates a flow diagram of mapping service group categories to user groups that have been given access to a given service group, in accordance with the principles of the present invention.
[0069] Reference is now made to FIGS. 8 and 9 that illustrate the Cloud administration process its hierarchy respectively, utilizing the tenant cloud instance manager as well as the manager of manager and the ability of uCloud platform to logically restrict and widen scope of Cloud Administration as well as monitoring;
[0070] It should be noted that reference throughout the specification to “tenants” includes both enterprises and service providers as “super-tenants”. Each Software Defined Cloud (SDC) has a management plane, as well as a Data Plane and Control Plane. The Management plane provisions, configures, and operates the cloud instances. The Control plane creates and manages the static topology configuration across network and security domains. The Data plane is part of the network that carries user networking traffic. Together, these three planes govern the SDC's abilities and define the logical boundaries of a given SDC. The Manager of Manager 604 in uCLoud Platform 100 which is accessible only to the uCloud Platform administrator 102 A, manages the tenant cloud instance manager 706 ( FIG. 10 ) in every tenant private cloud. The hierarchy of this management is shown in FIG. 9 .
[0071] Referring now to FIGS. 10 , 11 and 12 , the tenant cloud instance manager 706 is responsible for overseeing the management planes of various SDC's as well as any other virtual Applications that the tenant is running in its compute Nodes, network components and storage devices, respectively. The uCloud Platform 100 generates commands related to the management of Compute Nodes 120 a - n based on tenant cloud instance manager 706 and extended platform orchestrator. The extended platform orchestrator is responsible for intelligently dispersing commands to create, manage, delete, or modify components of a tenant's uCloud platform 100 , or the extended platform based on predetermined logic. These commands are communicated indirectly to the Controller Node 121 of a specific Enterprise environment. The controller node 121 then accesses the compute Nodes 120 a - n and executes the commands. The launched cloud instance (SDC) management planes are depicted as 708 a - n in FIG. 10 . The ability of the tenant cloud instance manager 706 to modify and delete SDC management plane characteristics (compute, network, storage, Users, and business processes is provided over the internet 111 . Tenants (depicted in FIG. 3 as 302 , 304 and 306 ) each have a Tenant cloud instance manager 706 viewable to through the web interface 104 depicted in FIG. 1 .
[0072] Again with reference to FIG. 8 , the monitoring platform 602 is not limited to one controller but rather, its scope is all controllers within the platform. The monitoring done by the controller 512 ( FIG. 5 ) is performed in a limited capacity, periodically gathering management plane information data in the extended platform for memory, CPU, network, storage utilizations. This information is gathered and then sent to the tenant cloud instance manager 706 .
[0073] Centralized management view of all management planes across the tenants is provided to uCloud Platform administrator 102 A through the uCloud web interface 104 depicted in FIG. 1 .
[0074] Reference is now made to FIG. 11 illustrating the logical flow of information from the uCloud Platform 100 to the Controller Node in a given Enterprise. The uCloud Platform 100 generates commands related to the management of Network components 122 and 123 based on tenant cloud instance manager and extended platform orchestrator element. The extended platform orchestrator is responsible for intelligently dispersing commands to create, manage, delete, or modify components of 100 , or the extended platform based on predetermined logic. These commands are communicated indirectly to the Controller Node ( 121 in FIG. 1 ) of a specific Enterprise environment 101 . The controller node then accesses the pertinent router nodes, and within them, the pertinent vAppliances, and executes the commands.
[0075] Reference is now made to FIG. 12 illustrating the logical flow of information from the uCloud Platform to the Controller Node in a given Enterprise. The uCloud Platform 100 generates commands related to the management of Storage components tenant cloud instance manager and extended platform orchestrator. The extended platform orchestrator is responsible for intelligently dispersing commands to create, manage, delete, or modify components of 100 , or the extended platform based on predetermined logic. These commands are communicated indirectly to the Controller Node 121 of a specific Enterprise environment. The controller node then accesses the pertinent storage devices and executes the commands.
[0076] Reference is now made to FIG. 13 illustrating the application-monitoring component of the uCloud Platform 100 in accordance with the principles of the present invention. The platform indirectly communicates with the Controller Node which monitors the application health. This entails passively monitoring a) the state of Enterprise SDC's ( 400 , 402 , 404 in FIG. 4 ), and b) the capacity of the Enterprise infrastructure. The Controller Node also actively monitors the state of the processes initiated by the uCloud Platform and executed by the Controller Node. The Controller Node relays the status of the above components to the uCloud Platform monitoring component 1000 .
[0077] Reference is now made to FIG. 14 illustrating the application-orchestration component of the uCloud Platform in accordance with the principles of the present invention. The app orchestrator performs the process of tracking service offerings that are logically connected to SDC's. It takes the requests from the service catalog and deterministically retrieves information on what compute Nodes and vAppliances are part of a given SDC. It launches service catalog applications within the compute nodes that are connected to a targeted SDC.
[0078] The process is as follows:
[0000] 1. receive request for launch of a virtual application from service catalog 508 .
2. retrieve information on destination of the request (which SDC in which tenant environment)
3. Retrieve information of what devices compute Nodes and vAppliances are involved in the SDC
4. once it determines the above, the app orchestrator sends a configuration to launch these virtual applications to the controller Node.
Additionally, the app orchestrator will be used in conjunction with the app monitor in the uCloud platform 100 as well as the monitoring controller present in the controller node in the extended platform to a) receive requests from controller node and b) access the relevant tenant extended platform, determines the impacted SDC, and c) perform appropriate corrective action.
[0079] Reference is now made to FIG. 15 illustrating the integration of the application-orchestration and application-monitoring components of the uCloud Platform in accordance with the principles of the present invention. FIG. 15 illustrates part of the Monitoring functionality of the uCLoud platform 100 . Through use of the monitoring controller, the app monitor collects health information of the extended platform (as detailed herein above). In addition, a tenant can define a “disruptive event”. In the event of a disruptive event the monitoring controller will alert the app orchestrator to perform corrective action. The monitoring controller performs corrective action by rebuilding relevant portions of extended platform control plane.
[0080] Reference is now made to FIG. 16 illustrating the big data component of the uCloud Platform 100 and the relationship to the monitoring component of the platform. Based on the data collected by the Controller Node 121 that is relayed to the Platform and stored in a Database, an analysis can be made of, a) SDC and compute nodes usage, and b) disruptive events reported. Heuristics of cloud usage is tracked by the Controller Node. Heuristic algorithmic analysis is used in 100 to understand aspects of tenant cloud usage.
[0000] SDC instance information is collected from the SDC management plane by the tenant cloud instance manager. (achieved by a) tenant cloud instance manager sending a command to the controller node via the message bus, b) controller node uses the command to retrieve collected information from the correct SDC management plane, c) information is relayed to tenant cloud instance manager, d) information is stored in a database)
SDC instance Information refers to Data about services usage, services types, SDC networking, compute, storage consumption data. This Data is collected continuously (via process outlined above) and archived to an external Big Data database ( 1303 , contained in 100 ).
Big data analytics engine processes the gathered information and performs heuristic big data analysis to determine cloud tenant services usage, services types, SDC networking, compute, storage consumption data, and then suggests optimal cloud deployment for tenant (through web interface in 100 ).
[0081] This analysis can contain a determination of high priority events, and report it to the relevant administrators 102 A, and 102 B. Additional analysis can be made using business metrics and return on investment computations.
[0082] Reference is now made to FIG. 17 illustrates the process of deploying uCloud within an Enterprise environment. Using gathered information on compute nodes 120 a - n , uCloud Platform 100 creates a customized package that contains a Controller Node 121 , designed for the Enterprise 101 . Administrator 102 B then downloads and installs Controller Node 121 into the Enterprise environment 101 . The uCloud Platform then orchestrates the infrastructure within the Enterprise environment, via the Controller Node. This includes configuration of router nodes 122 , firewall node 123 , compute Nodes 120 a - n , as well as any storage infrastructure.
[0083] FIG. 17 represents a holistic view of the cloud management platform capabilities of uCloud Platform. The platform is separated into the hosted platform 100 and the management platform.
[0084] The uCloud Platform 100 can support many tenants recalling that a tenant is defined as an enterprise or a service provider. The multi tenant concept can be seen in FIG. 2 , as well as in FIG. 3 . The tenant environment prior to deployment of uCloud is a collection of Compute Nodes. Post uCloud deployment, the environment, now called a private cloud, comprises an extended platform and compute nodes. The extended platform comprises of a limited number of Nodes dedicated for the logical creation of clouds (SDC's). The compute Nodes are used as Enterprise resources, and can be part of a single or multiple SDC's, or software defined clouds. The SDC concept is seen in FIG. 4 . This is referred to as the “logical view” of the private cloud. The division of the extended platform and the compute nodes is seen in FIG. 1 . This will be referred to as the “hardware view” of the private cloud. The combination of the logical and hardware views is seen in ( FIG. 18 ). As mentioned, the extended platform consists of several Nodes (servers). Each Node will run specific types of virtual Appliances, or vAppliances, that regulate and create logical boundaries for an SDC. Every SDC will contain a specific set of vAppliances. The shaded regions of (FLOW 1) represent exclusive use of a set of vAppliances by a specific SDC. The Compute Nodes of a private cloud, seen in FIG. 1 and in FLOW as C-N, are a resource that can be shared between multiple SDC's. This sharing concept is seen in FIG. 18 .
[0085] The uCLoud Platform manages SDC's by providing several features that will assist a tenant in operating the private cloud. These features include, but are not restricted to, a) service catalog of virtual applications to be run on a given SDC, b) monitoring of SDC's, c) Big Data analytics of SDC usage and functionality, and d) hierarchical logic dictating access to SDC's/virtual applications/health information/or other sensitive information. The process of performing each feature has been shown in FIGS. 5-14 .
[0086] The uCloud Platform configuration process is summarized as follows: Using gathered information on compute nodes 120 a - n , uCloud Platform 100 creates a customized package that contains a Controller Node 121 , designed for the Enterprise 101 . 102 B then downloads and installs 121 into the Enterprise environment 101 . The uCloud Platform then orchestrates the infrastructure within the Enterprise environment, via the Controller Node. This includes configuration of router nodes 122 , firewall node 123 , compute Nodes 120 a - n , as well as any storage infrastructure. The combination of all uCLoud Platform components in the hosted and extended platforms allows for the operation of a multi-tenant, multi-User, scalable Private cloud.
[0087] FIGS. 22-24 illustrate embodiments of systems and methods for secure transmission of data to and from a tenant environment to the uCloud Platform to the tenant environment. FIG. 22 is a block diagram of an overview of an embodiment of a system according to the current invention. FIGS. 23 and 24 are block diagram of embodiment of a system according to the current invention.
[0088] Due to the nature of secure networking, it is not ideal to allow direct external access to a secure tenant environment. In order to allow the transmission of data from the uCloud Platform to a tenants environment, a system is created in the following manner. A tenant is onboarded initially, reserving certain nodes for the uCloud extended platform. This extended platform includes router nodes, firewall nodes, as well as a controller node 121 . This controller node 121 will contain several components. One such component is the tElastic Controller 2310 . The tElastic Controller 2310 is a vAppliance, similar to the router, firewall, DDNS, and bridge router vAppliances shown in FIG. 18 . The tElastic Controller 2310 serves as a Data stream aggregator, and will receive information from the uCloud Platform via a secure datastream.
[0089] Appropriate templates are downloaded in the nodes 120 reserved for the extended platform, an element corresponding to the tElastic Controller 2310 is created in the uCloud Platform. This element is called the Q. Together, both components will create a secure channel through which the tElastic Controller 2310 can receive messages, and execute commands.
[0090] In order to initial configuration of the tElastic Controller 2310 , the tenant is onboarded, tenant specifies nodes for Extended Platform, templates are downloaded for vAppliances, and a connection is established with Q in the uCloud Platform. In the initial connection, authentication of the tElastic Controller is performed by the uCloud Platform. The data stream is created through which the Q will communicate messages and commands to the tElastic Controller 2310 .
[0091] In operation, in the exemplary process, the application orchestrator utilizes the secure data stream to execute a certain result pertaining to the compute nodes 120 of a tenant's private cloud. The application orchestrator receives a compute node related request from a manager within uCloud Platform. The application orchestrator is in cooperation with the Q to create a simple data packet containing instructions for the tElastic Controller, as well as a return address. The tElastic Controller 2310 receives the data packet and executes the commands in the appropriate compute nodes 120 . The tElastic Controller 2310 sends a message confirming the completion of the task to the uCloud Platform via a protocol such as RestAPI call (show in FIG. 1 in 100 ).
[0092] The Q receives data packets via a redundant system of messaging servers. In order to guarantee delivery of the messages, the following process is implemented to the system. Messaging servers of Q receive data packet with instructions for/requests for information from compute nodes 120 of the tenant private cloud. These instructions are sent to the tElastic Controller. Messaging servers save a copy of the message in memory as well as in a file system. The Q sends messages to controller node 121 . If the tElastic Controller 2310 is overcapacity due to requests or the controller node 121 is non-responsive, the Extended Platform Monitor notifies the tenant administrator of the event. After the controller node 121 becomes available, the queued messages are delivered.
[0093] FIGS. 25 and 26 illustrate alternate embodiments of the invention which facilitate use of the secure data stream to execute network related instructions within the configured capabilities of a tenant's private cloud. The application orchestrator receives a network related request (for example router nodes, firewall nodes, vAppliances) from a manager within the uCloud Platform. The application orchestrator coordinates with the Q to create a simple data packet containing instructions for the tElastic Controller 2310 , as well as a return address. The tElastic Controller 2310 receives the data packet and executes the commands in the appropriate network related device, or through the extended platform monitor. The tElastic Controller 2310 sends a message confirming the completion of the task to the uCloud Platform via protocol such as a RestAPI call (seen in FIG. 1 in 100 ).
[0094] The Q receives data packets via a redundant system of messaging servers. In order to guarantee delivery of the messages, the following process is implemented to the system. Messaging servers of Q receive data packet with instructions for/requests for information from compute nodes 120 of the tenant private cloud. These instructions are sent to the tElastic Controller. Messaging servers save a copy of the message in memory as well as in a file system. The Q sends messages to controller node 121 . If the tElastic Controller 2310 is overcapacity due to requests or the controller node 121 is non-responsive, the Extended Platform Monitor notifies the tenant administrator of the event. After the controller node 121 becomes available, the queued messages are delivered.
[0095] While this disclosure has described certain embodiments and generally associated methods, alterations and permutations of these embodiments and methods will be apparent to those skilled in the art. Accordingly, the above description of example embodiments does not define or constrain this disclosure. Other changes, substitutions, and alterations are also possible without departing from the spirit and scope of this disclosure, as defined by the following claims. | Method and Apparatus for rapid scalable unified infrastructure system management platform are disclosed by discovery of compute nodes, network components across data centers, both public and private for a user; assessment of type, capability, VLAN, security, virtualization configuration of the discovered unified infrastructure nodes and components; configuration of nodes and components covering add, delete, modify, scale; and rapid roll out of nodes and components across data centers both public and private. | 7 |
This invention relates in general to a new and improved orthodontic appliance for orthodontically treating a patient, and more particularly to a new and improved bracket that may be used in combination with other brackets and appliances which includes multiple archwire slots, and still more particularly to a new and improved bracket having a closed archwire slot preferably functioning to allow crown tipping, limit root uprighting and controlling torque, and a horizontally open rectangular archwire slot for controlling tip, torque and rotation.
BACKGROUND OF THE INVENTION
Heretofore, it has been well known to provide orthodontic brackets having multiple archwire slots for receiving archwires and particularly archwire slots that are open for receiving rectangular archwires for the use in treating patients with the edgewise technique and slots for receiving archwires in the treatment of patients during the Begg or light wire technique, such as shown in U.S. Pat. No. 2,196,516.
It has also been well known to provide orthodontic brackets having means for accommodating crown tipping, root uprighting, and torquing functions, such as disclosed in U.S. Pat. Nos. 4,877,398 and 5,125,832. Brackets of this type are viewed as having a Tip Edge® slot for practicing the Tip Edge® technique. Tip Edge® is a registered trademark owned by TP Orthodontics, Inc. of Westville, Ind. While the brackets in these patents have been designed for using round or rectangular wire, they particularly perform torquing functions with rectangular wire and allow the movement of teeth along the archwire and the arch.
Further, the brackets disclosed in the above patents include vertically extending slots or openings for receiving the tails of uprighting springs to perform a root uprighting function where desired. Additionally, U.S. Pat. No. 4,842,514 discloses a type of uprighting spring that may be used with brackets having vertical openings.
It has also been known to provide an orthodontic bracket having a pair of contiguous labiobuccally opening archwire slots, one of which allows tipping and uprighting movement, and the other of which provides torquing movement, as shown in U.S. Pat. No. 4,842,512. It has also been known to provide a bracket having a pair of contiguous archwire slots which allows crown tipping, limits root uprighting, and controls torquing, while the other slots functions to stabilize tooth movement in three dimensions as sold by TP Orthodontics, Inc. of Westville, Ind., and illustrated in TP's 1998 product catalog on page 32.
Moreover, it has been known to provide an orthodontic bracket including a main archwire slot that allows crown tipping, root uprighting, and torquing functions, and additionally a lumen or tunnel which produces a final uprighting function with the use of a highly flexible archwire without the use of individual uprighting springs, as shown in U.S. Pat. No. 6,682,345.
SUMMARY OF THE INVENTION
The present invention relates to an orthodontic appliance, and particularly an orthodontic bracket, including a horizontally opening rectangular archwire slot to receive a rectangular archwire for treating patients under the edgewise or straight-wire technique, a closed archwire slot having means coacting with an archwire to treat patients with the Tip Edge® technique, and a vertical slot for accommodating an uprighting spring to produce uprighting forces. A recess is provided for allowing part or all of the uprighting spring head to be received and essentially become invisible from the labial or front of the bracket for enhancing the cosmetics of the brackets.
Thus, the bracket of the invention gives an orthodontic practitioner the option to use a closed archwire slot to orthodontically treat malpositioned teeth and particularly for easily moving teeth along an arch by employing the Tip Edge® technique, as well as providing a horizontally opening rectangular slot for receiving a main aligning archwire particularly during the final stages of orthodontic treatment when employing the edgewise or straight-wire technique. The bracket of the invention also includes a vertical slot for accommodating the use of an uprighting spring to give the orthodontic practitioner the option of using such a spring where uprighting of teeth is desired.
Additionally, the bracket of the invention consists of a front part which is configured to provide a horizontally open rectangular archwire slot, and a rear or back part of a plastic resin molded to the front part and configured to provide a closed mesiodistally extending archwire slot preferably for employing the Tip Edge® technique. The front section may be of any desired material, such as stainless steel or another metal, ceramic, or plastic, while the molded rear section may be of an acrylic of a suitable hardness to withstand the forces of an archwire without distorting the slot.
It is therefore an object of the present invention to provide a new and improved orthodontic appliance in the form of an orthodontic bracket that includes a horizontally opening rectangular archwire slot, and a closed archwire slot capable of allowing crown tipping, limiting root uprighting, and controlling torquing to treat patients with the Tip Edge® technique.
A further object of the present invention is to provide a new and improved orthodontic bracket that includes a horizontally opening archwire slot and a closed archwire slot, together with a vertical slot for accommodating an uprighting spring for producing tooth uprighting movements.
A still further object of the present invention is to provide a new and improved orthodontic bracket made of a front section of metal, ceramic or plastic, having a horizontally opening rectangular archwire slot, and a rear section of a suitable plastic resin molded to the front section and configured to define a closed archwire slot.
Other objects, features and advantages of the invention will be apparent from the following detailed disclosure, taken in conjunction with the accompanying sheets of drawings, wherein like reference numerals refer to like parts.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front perspective view of the bracket according to the present invention showing in dotted lines the closed archwire slot and in phantom a rectangular archwire in the closed slot, and illustrating a partially fragmentary view of an uprighting spring;
FIG. 2 is an exploded view of the bracket of FIG. 1 to illustrate the method of making the bracket wherein the base, which includes the inner archwire slot, may be configured of a suitable plastic resin and then molded onto the front section of the bracket;
FIG. 3 is a top plan view of the bracket of FIG. 1 ;
FIG. 4 is a side elevational view of the bracket of FIG. 1 ;
FIG. 5 is a vertical sectional view of the bracket of FIG. 3 and taken substantially along line 5 - 5 thereof;
FIG. 6 is a front elevational view of the bracket of FIG. 1 ;
FIG. 7 is a horizontal view of the bracket taken along line 7 - 7 of FIG. 4 ;
FIG. 8 is a modification of the invention and differs from the embodiment of FIGS. 1 to 7 in that the tie wing tips are spaced apart and not tied together, no vertical slot is provided, and the base of the front section does not include an enlarged portion;
FIG. 9 is a front elevational view of the embodiment of FIG. 8 ;
FIG. 10 is a further modification of the invention which differs from the embodiment of FIGS. 8 and 9 in that the tie wing tips are connected at the front face of the bracket with reinforcing bars; and
FIG. 11 is an end elevational view of the embodiment of FIG. 10 .
DETAILED DESCRIPTION OF THE INVENTION
The bracket of the present invention provides a combination bracket that includes a horizontally open rectangular slot for rectangular archwire to be used in connection with the usual straight-wire technique, or other edgewise techniques, and a closed archwire slot to be used in connection with the Tip Edge® technique wherein the closed slot includes means for coacting with the archwire to allow crown tipping, limit root uprighting to a predetermined angulation, and to control torquing. The standard horizontally opening archwire slot for rectangular archwire controls tip, torque and rotation. With respect to the horizontally opening archwire slot, it may or may not include single tie wings or double tie wings. The tie wings may be tied together to provide rigidity, or they may be separated as in the standard type of edgewise bracket. Moreover, with respect to the horizontally opening edgewise slot, it may be provided with means for closing the slot without the use of ligatures wherein it would be a self-ligating bracket. Where tie wings are provided, ligatures of the usual type may be used to retain the archwire in the slot such as the standard elastic ligatures or the standard wire tie ligatures.
Inasmuch as the bracket of the invention includes a horizontally opening archwire slot together with a closed archwire slot, the bracket may be constructed of two parts or sections permanently joined during manufacture, wherein the front or buccolabial part or section forming the open archwire slot may be made of the usual stainless steel, ceramic or plastic material, and the rear or lingual part or section would be molded of a suitable plastic resin to the backside of the first part and which would constitute the base of the bracket for bonding to a tooth. The rear section would also be configured during molding to define the closed archwire slot behind the main open archwire slot. Preferably, the rear section will be of a suitable plastic resin, such as an acrylic, which would be able to withstand any archwire forces that would exist between the bracket slot and the archwire during treatment and the application of forces to the bracket.
In this regard, the acrylic molded section would have built into its shape not only the arcuate bonding surface compatible with the tooth for which it is designed so that it would fit properly on a tooth, but also the tip, torque and rotation values that are intended to be incorporated into the bracket. In this respect, the bracket, which would define the horizontally opening rectangular slot, may be of a generic form for molding to a base having the particular prescription values.
Referring now to the drawings, the first embodiment of the invention is shown in FIGS. 1 to 7 , and second and third embodiments of the invention are shown in FIGS. 8 to 11 . The difference between the embodiments is in the structure of the front section of the bracket that defines the horizontally opening rectangular archwire slot as hereafter explained.
Referring now particularly to the embodiment of FIGS. 1 to 7 , the bracket is generally designated by the numeral 14 and includes a front or buccolabial section or part 16 and a rear or lingual section or part 18 .
The front section 16 of the embodiment illustrated is formed by any suitable method to define the horizontally opening rectangular archwire slot 20 adapted to coact with a main rectangular aligning archwire and twin tie wings 22 . Such parts made of metal may be machined or cast, while parts made of ceramic or plastic are usually molded. Each tie wing includes dual opposed tips or ears for receiving a ligature to retain the archwire in the archwire slot. With respect to the embodiment disclosed in FIGS. 1 to 7 , the tie wing tips are interconnected with each other by means of a horizontal reinforcing bar. However, it should be appreciated that the front section need not include the reinforcing bar and therefore define spaced apart tie wings at the buccolabial face, as shown in the embodiment of FIGS. 8 and 9 . Moreover, it should be appreciated that the front section could merely be formed to have a single tie wing. The ligatures may be of wire or elastic in accordance with the desires or the orthodontist. Additionally, it should be appreciated that the front section could have a form of a self-ligating slot wherein additional mechanism and means would be provided to open and close the slot without the need for ligatures to retain the archwire in the slot. In all of the potential configurations, the front section would include a horizontally opening rectangular archwire slot for receiving a rectangular archwire particularly where the bracket would be used to practice the edgewise or straight-wire technique. However, it should be appreciated that a round wire could be used in some stages of treatment in the rectangular archwire slot if so desired by a particular orthodontist.
The front section 16 also includes an enlarged lingual base portion 24 to which the lingual section 18 would be molded. In the embodiment of FIGS. 1 to 7 , the portion 24 is nearly as high as the tips of the tie wings and defines with the tie wings upper and lower cutouts 26 and 28 in which the ligatures are received when they are applied to the bracket for retaining an archwire in the horizontally opening rectangular archwire slot 20 . The backside of the base 24 is substantially flat although, as will be explained below, it includes a vertically extending groove to coact with the lingual section 18 for defining a vertical slot to receive the tail of an uprighting spring as illustrated in the drawings.
While the lingual section 18 is shown separated from the buccolabial section 16 in FIG. 2 , it will be appreciated that when the bracket is fully constructed it will be molded onto the buccolabial section and be integral therewith. As previously mentioned, the front or buccolabial section 16 of the bracket may be made of any suitable material, such as metal and particularly stainless steel, ceramic, plastic, or any combination thereof. Further, it may be of a standard sized part inasmuch as tip, torque and rotation values in accordance with any prescription can be built into the rear or lingual section 18 .
The lingual section 18 of the bracket 14 is preferably formed of a suitable plastic resin, such as an acrylic, and molded onto the front section 16 of the bracket during the manufacture of the bracket. Any suitable acrylic or equivalent material may be used to mold the rear section onto the buccolabial section as long as it has sufficient strength to withstand the forces imparted relative to the archwire slot formed in the base section without deforming. Preferably, the archwire slot, generally designated 30 , has a configuration as disclosed in U.S. Pat. Nos. 4,877,398 and 5,125,832 as above mentioned, which is configured to accommodate crown-tipping functions, root-uprighting functions, and torquing functions, in accordance with the Tip Edge® technique. For purposes of clarity, the disclosures in these patents are incorporated by reference. When viewed from the front, as generally seen in FIG. 2 , the slot generally has a bow-tie shape. The slot generally includes opposed surfaces defined by angular segments which coact to define fulcrums about which the bracket can tip relative to the archwire. A standard rectangular archwire is preferably used in the slot 30 , although it should be appreciated that a round archwire may be used in that slot for certain treatment phases as chosen by the orthodontist. The ability to provide the crown tipping and root uprighting functions facilitates the movement of teeth along the archwire to close spaces.
It will be appreciated that the archwire slot formed in the lingual section 18 in coaction with the rear surface of the base 24 of the buccolabial section 16 is a closed archwire slot that does not require any ligatures to retain the archwire in the slots of these brackets. The archwire is merely threaded through the slots of the various brackets when it is desired to utilize the Tip Edge® slot 30 in the base. With this in mind it should be appreciated that the orthodontist would have the option to use the horizontally opening rectangular archwire slot or to use the Tip Edge® slot during various phases of orthodontic treatment of a patient.
It should be further recognized that while as above mentioned both round and/or rectangular archwires may be used in either of the slots 20 or 30 , the type of wire may vary depending upon the desired treatment of an orthodontist. For example, the wire may be stiff or it may be highly yieldable, such as a nickel titanium wire.
As seen in FIGS. 1 to 7 , the lingual section 18 is preferably sized overall slightly larger than the base 24 of the buccolingual section 16 in order to provide an overlapping lip 34 that overlaps the base 24 to enhance the connection between the sections 16 and 18 . As also seen in the drawings, the lingual surface of the lingual section 18 defines an arcuate surface 36 formed to conform with the buccolabial face of a tooth when bonding the bracket to a tooth. The arcuate shape may vary depending upon which tooth the bracket is to be mounted. Additionally, the arcuate face 36 would preferably have a roughened surface of any suitable type in order to enhance its gripping action with any bonding material that is used to attach the bracket or bond the bracket to a tooth.
The bracket 14 preferably includes a vertical slot for receiving the tail of a standard uprighting spring, as seen in the drawings. An uprighting spring 40 is shown with a tail 41 that extends through a vertical slot 44 . The uprighting spring also includes a head or coil section 42 and a lever arm 43 for connecting to the archwire. In the embodiment illustrated, the vertical slot 44 is formed by a vertical groove in the rear face of the base 24 of the front section 16 and the front flat face of the back section 18 . Further, the upper end of the front section 16 is provided with a notch 46 that coacts with a notch 48 in the back section 18 to define a recess for the head 42 of the uprighting spring to essentially hide the uprighting spring from the buccal or labial side. It will be appreciated that the tail 41 of the uprighting spring may be clipped off or bent over backward to anchor the uprighting spring in the vertical slot. The uprighting spring would only be used during certain aspects of the orthodontic treatment of a patient where an uprighting function would be desired.
Accordingly, it will be appreciated that during the manufacture of the bracket the lingual section 18 will be molded onto the front section 16 to provide a bracket having a horizontally opening rectangular archwire slot and a closed mesiodistally extending Tip Edge® archwire slot as well as a vertical slot for an uprighting spring. Thus, any desired prescription may be incorporated into a bracket by adjusting the formation of the lingual section when it is molded onto the buccolabial section.
The embodiments of FIGS. 8 to 11 are preferred as the front section differs in not including an enlarged portion behind the tie wing tips. Moreover, the embodiment of FIGS. 8 and 9 differs from the embodiment of FIGS. 1 to 7 in that it includes a typical twin tie wing configuration wherein the twin tie wing configuration allows each of the tie wings to be projecting from the base of the bracket. FIGS. 10 and 11 show the same embodiment as FIGS. 8 and 9 except for the reinforcing bar that extends between the upper and lower tie wing tips. Further, while the embodiments of FIGS. 8 and 9 , 10 and 11 do not include a vertical slot, it should be appreciated that they could be structured with a vertical slot as in the embodiment of FIGS. 1 to 7 , and that the vertical slot would be essentially disposed between the horizontally open rectangular archwire slot and the Tip Edge® slot. The vertical slot may be formed in the front section or the rear section.
The embodiment shown in FIGS. 8 and 9 is generally indicated by numeral 14 A and includes a front section 50 and a rear or lingual section 52 . The front or buccolabial section 50 includes spaced apart tie wings 54 which differ from the tie wing configuration of FIGS. 1 to 7 in that the tie wings are not connected together by a reinforcing bar at the upper and lower tie wing tips or ears. Between the tie wing tips a horizontally opening rectangular archwire slot 56 is defined and of the same form as in the embodiment of FIGS. 1 to 7 for receiving particularly in the final stages of treatment a rectangular archwire. As above mentioned, the base of the front section 50 differs from the base of the front section in the embodiment of FIGS. 1 to 7 in that it does not include an enlarged portion to which the base section is molded. Further, the base extends straight back or lingually from the bottom of the areas that would receive a ligature, as seen in FIGS. 8 and 9 , to define upper and lower horizontally extending faces 58 and 60 .
The rear or lingual section 52 is molded onto the backside of the front section 50 in substantially the same manner as the rear section is molded onto the front section in the embodiment of FIGS. 1 to 7 and configured to include a Tip Edge® slot 62 much like the Tip Edge® slot that is formed in the rear section of the embodiment of FIGS. 1 to 7 . A rectangular archwire is shown in phantom in the Tip Edge® slot 62 . As with respect to the first embodiment, the rear section is molded of a suitable acrylic of such a hardness that it can receive and bear the forces of an archwire during treatment of a patient without distortion of the Tip Edge® slot. As in the first embodiment, the orthodontist would have the option to use the bracket by threading a wire through the Tip Edge® slot for performing the Tip Edge® technique or by using a rectangular archwire for engagement with the horizontally opening rectangular archwire slot 56 in the front section particularly for performing the standard straight-wire or edgewise technique. While the final stages of treatment can be completed by use of either of the archwire slots, it would be appreciated that use of the horizontally opening archwire slot would generally be preferred.
Moreover, it would be appreciated with respect to this embodiment as in the embodiment of FIGS. 1 to 7 rectangular or round archwires may be used whether of the standard stiffness or of the super flexible type depending upon the phase of treatment desired by the orthodontist.
The modified bracket shown in FIGS. 10 and 11 is generally indicated by the numeral 14 B and includes a front or buccolabial section 64 and a rear or lingual section 66 . The front section likewise includes a pair of tie wings 68 having upper or lower tie wing tips or ears and a horizontally opening rectangular archwire slot 70 . The rear section 66 includes a Tip Edge® archwire slot 72 and the rear section is molded to the back of the front section in the same manner as in the embodiment of FIGS. 10 and 11 . The molding overlaps at least a part of the rear section in order to obtain a secure connection and provide an integral bracket with a base. Likewise, the acrylic base would be formed at the lingual face to fit on a particular tooth and to include built-in tip, torque and rotation values, particularly for the horizontally open archwire slot. This embodiment differs from the embodiment of FIG. 8 only in that the tie wing tips are connected at the buccolabial face with reinforcing bars 74 much like the embodiment of FIGS. 1 to 7 . The base of the front section 64 is formed in the same manner as the base of the front section 50 in FIGS. 8 and 9 , and the front section may be of any suitable material such as stainless steel, ceramic or plastic.
The function of the embodiment of FIGS. 10 and 11 is substantially identical to the function of FIGS. 8 and 9 in that an orthodontist may choose to use either the Tip Edge® slot 72 or the horizontally opening rectangular slot 70 during treatment of a patient in accordance with the desired stage of treatment.
It should also be appreciated that while the configuration of the brackets in the embodiments illustrated as seen from the labial and/or mesiodistal views are somewhat square in overall shape. They may be rhomboidally shaped from either of those views in order to follow certain prescription specifications. Also, as mentioned with respect to the embodiment of FIGS. 1 to 7 , the configuration of the embodiments of FIGS. 8 to 11 could be such as to include means for defining the horizontally opening archwire slot in the front section to be self-ligating, thereby eliminating the necessity of using ligatures on the front section in order to retain the archwire in the front archwire slot.
It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention, but it is understood that this application is to be limited only by the scope of the appended claims. | An orthodontic appliance, and more particularly an orthodontic bracket to be used in conjunction with other brackets on centrals, laterals, cuspids and bicuspids for moving teeth in the orthodontic treatment of patients, and which includes a closed archwire slot that preferably functions to allow crown tipping, limiting root uprighting, and controlling torque, and a horizontally open rectangular archwire slot for controlling tip, torque and rotation in the final stage of patient treatment. The bracket is made by configuring a front section having a horizontally open rectangular archwire slot of metal, ceramic or plastic, and molding a rear or back section of a suitable plastic resin onto the front section such that the rear section preferably includes a closed mesiodistally extending archwire slot. | 0 |
FIELD OF THE INVENTION
The present invention relates generally to ophthalmological diagnostic equipment and particularly to an ophthalmological self-test unit which combines features of a standard Amsler grid with an attention focusing device in a convenient package for use in assisting a patient to consistently evaluate macular degeneration over time.
BACKGROUND OF THE INVENTION
Macular degeneration is a retinal disease which is the leading cause of central vision loss among people over the age of 65. Macular degeneration is a process of wear and tear in the macula, the portion of the retina responsible for sharp central vision and color perception. It usually affects both eyes, causing vision loss which may be either gradual or abrupt.
Referring to FIG. 1, a cross sectional view of a human eye is shown. The human eye is designed for panoramic viewing, allowing an individual to see objects straight ahead as well as to the side. As light enters the eye 10, it passes through the cornea 11 and pupil 12, and is focused by lens 13 into an image on retina 14. This image is converted by the retina into electrical impulses which are transmitted via optic nerve 15 to the brain. Macula 16 is the particular portion of the retina at which sharp central vision is processed.
The macula consists of multiple layers as is shown in FIG. 2. Innermost layer 18 of macula 16 is comprised of light sensing cells which produce sharp central vision. Two underlying layers nourish and help remove waste materials from these light sensing cells. The light sensing cells or "cones" as they are commonly referred to, are responsible for color perception and central vision. These cones shed their outer segments as waste products through normal metabolism. Second layer 20, known as the "retinal pigment epithelium", nourishes the cones and digests these shed outer segments during the day. Finally, third layer 22, known as the "choroid", comprises blood vessels that transport nutrients and carry away waste material from the macula region.
Macular degeneration is the common name for the age-related disease where macular retinal pigment epithelium cells function less well than normal. As a result, waste removal and nutrition of the cones suffers, causing central vision loss. Macular degeneration can be further classified into two varieties: a "dry type" and a "wet type". Dry type macular degeneration occurs when the outer segments of the light sensing cones, which are continuously being shed, are unable to be digested by the pigment epithelium layer of the macula. Consequently the pigment epithelium layer swells and eventually dies after accumulating too much undigested material from the cones. Yellowish deposits of this waste material gradually develop under the retina between the choroid and pigment epithelium. In this "dry type" macular degeneration, the vision loss is characterized by gradual blurring or partial obscuration of central vision as a result of parts of the macula having begun to die, creating areas where the cones are no longer functional. Clinically, the person suffering from this type of the disease may experience relatively mild central visual distortion with straight lines appearing bent or wavy.
In the second or "wet" type of this disorder, more severe and sudden vision loss may occur. This sort occurs when abnormal new blood vessels or "neovascular membranes" grow from the choroid through the damaged pigment epithelium and under the macula. These neovascular membranes are fragile and are prone to hemorrhage which results in severe distortion of the macular tissue. As a result, the light sensing cells (cones) become separated from their source of nutrients and suffer further damage due to eventual scarring as the hemorrhage contracts over time. With this type of disorder, dark or "missing" spots in the central vision may occur rapidly and with little warning due to these hemorrhagic changes. Fortunately, intervention with laser therapy early in this process may often prevent additional vision loss.
In order to detect changes early enough such that laser is beneficial, doctors use a variety of tests designed to evaluate the health of the macula. One such test is termed the "Amsler grid" and utilizes a uniform grid pattern of crossing lines to test central vision. The use of this grid reveals distortions and other abnormalities in the central field of vision. A patient once having been diagnosed with macular degeneration is typically required to monitor their vision with an Amsler grid on a daily basis in order to detect subtle signs of increasing distortion which may indicate an evolving neovascular membrane. Since this "wet" form of the disease may occur suddenly and with rapid vision loss, daily follow up is essential to ensure that intervention with laser treatment is instituted early enough to help prevent further visual damage.
The Amsler grid is known in the art (See FIG. 3). The use of the Amsler grid requires that a patient stand about a foot away from the grid itself, and, while wearing one's own glasses, covering or closing one eye while focusing on the center of the grid. In order for the Amsler grid to be effective, the patient must note any changes that occur over time and repeat the above process on a daily basis. While Amsler grids have been known for years in the art, the use of the grid in a practical setting by patients has revealed a number of every day problems.
Because of the nature of this degenerative eye disorder, daily use is required in order to track changes associated with the disorder such that early effective treatment can be implemented. As such, the grid must be accessible and easy to use in order to encourage use of the product. Accordingly, any improvements to the design of the grid which would improve the overall accessibility and ease of use would facilitate regular use. Use by patients has revealed that improvements to the basic grid design which facilitate the daily use of the device result in more consistent use of the product.
Secondly, the grid must also be sufficiently sized to accommodate the self testing of both the user's central and peripheral vision. A grid which is too small won't allow for the evaluation of a sufficient field of vision, yielding inaccurate or incomplete test results. However, the grid must not be so large as to become a nuisance to manipulate or store.
The degenerative nature of the eye disorder also requires that a patient be able to monitor the progress of the disease by somehow recording the particular areas of concern associated with each of the patient's eyes for a given baseline time frame, in order to determine whether or not any further damage has arisen. While the original grids were mass produced on paper products, any improvement which would assist the patient to identify and log the current eye condition as compared to a baseline condition would be desirable in order to help the patient in evaluating changes to his or her vision.
As described previously, the basic architecture of the Amsler grid includes a grid area which is utilized by the patient to assist in the evaluation of their vision. In practice patients have suggested that because of the poor contrast of the fixation target of the grid, that they often find themselves, and their eye that they are testing, wandering after but a few brief seconds when using the grid. Accordingly, any means of helping to assist a patient to keep their attention focused toward a single central location on the grid would assist in improving the accuracy of the self diagnostic tool.
The present invention improves on the prior art by providing a central attention focusing means which is designed to hold the patient's attention squarely centered on the grid so as to allow for a more accurate self diagnosis. The present invention includes an erasable re-writable surface to assist patients in identifying changes to their vision and progression of the disorder. The present invention also packages the grid, central focusing means and re-writable surface in a package which will assist the patient in performing the test on a daily basis, helping to remind the patient to conduct the self diagnosis while minimizing the possibility of loss of the grid itself and the baseline information upon which is stored.
SUMMARY OF THE INVENTION
It is the object of the present invention to provide an improved device such as an Amsler grid for assisting a patient with macular degeneration to establish a baseline configuration associated with the amount of degeneration that has occurred in each eye and for monitoring subsequent changes in their vision.
It is a further object to provide an improved device such as an Amsler grid which is conveniently packaged to facilitate daily use by a patient.
It is another object of the present invention to provide an improved device such as an Amsler grid which maintains a patient's attention focused squarely on the grid so as to allow for a more accurate evaluation of the patient's vision.
It is another object of the present invention to provide an improved device such as an Amsler grid packaged in a convenient medium so as to be able to facilitate easy location of the grid in well traveled portions of the patient's residence.
In summary, the present invention is an improved ophthalmological self test unit for assisting in the self evaluation of the degenerative effects of certain eye disorders. The self diagnostic ophthalmological device includes a grid area having a re-writable surface which is fixably attached to a magnetic backed material for ease of attachment to any metallic surface such as might often be found on a refrigerator. Disposed on the grid surface is a central focusing means for assisting in the focusing of a patient's attention to the central portion of the grid structure. In an alternative embodiment a polar grid is utilized along with the central focusing means mounted upon the magnetic backed material.
BRIEF DESCRIPTION OF THE DRAWINGS
Initial objects and features of the invention will be more readily apparent from the following detailed description and appended claims when taken in conjunction with the drawings, in which:
FIG. 1 is a cross section diagram a human eye.
FIG. 2 is a cross section of a macular portion of the human eye.
FIG. 3 is a prior art Amsler grid.
FIG. 4 is a grid structure according to one embodiment of the present invention.
FIG. 5 is a block diagram of a circuit associated with the focusing means of one embodiment of the present invention.
FIG. 6 is a cross section of the grid structure of FIG. 4.
FIG. 7 is an alternative grid structure according to a second embodiment of the present invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Referring to FIG. 4, there is shown a diagram of a grid 100 according to one embodiment of the present invention. In this embodiment, the grid 100 is comprised of a grid area 110 which includes twenty horizontal lines 120 and twenty vertical lines 130. The horizontal and vertical lines are spaced to form one hundred individual boxes 140 in an overall grid size of 5"×5". Those ordinarily skilled in the art will recognize that as the grid size is made smaller, less area of the peripheral vision associated with a particular patient may be mapped by the diagnostic tool. Accordingly, a minimum grid size of approximately four inches square (4×4) should be utilized in order to effectively cover the region associated with the macula. Similarly, those ordinarily skilled in the art will recognize that grids exceeding or much bigger than represented will offer little or no help in diagnosing the progress of the disease because of the centrally located distortion effects associated with this particular eye disorder. Accordingly, a maximum grid size of approximately eight inches square (8×8) should be utilized. A grid size of five inches by five inches is preferred.
The spacing of the vertical/horizontal lines is done to accommodate the recognition by the patient of discrepancies from a norm. As the grid lines are drawn tighter and tighter together, the "busyness" of the grid tends to mask certain manifestations of the disorder. Accordingly, a grid square resolution on the order of between 0.05 and 0.09 square inches is recommended, with a grid size of 0.0625 square inches used in one embodiment.
Disposed on grid area 110 is focusing means 150. In one embodiment, focusing means 150 is comprised of a focusing pattern comprising a pair of red diagonal lines 152 and 154 which extend from the respective corners formed by grid horizontal and vertical lines 120 and 130 through the center of grid area 110. Alternatively, the focusing pattern may be a target cross hair as would be commonly found in a gun sight.
At the center of focusing means 150 is light source 156. In one embodiment, light source 156 is a light emitting diode (LED). In use, patients have reported that the centrally located light source coupled with red diagonal focusing lines serve to center the patient's attention fixedly on the central portion of the grid thereby allowing for repeatable test results. Alternatively, light source 156 may be a light bulb, a mirror, a rhinestone or other sufficiently light emitting or reflecting object as is known in the art. Light source 156 must be sized sufficiently small to avoid masking any centrally located vision distortion or defects. Accordingly, the light source should be sized to be less than 0.50 inches, and in one embodiment, the light source is an LED which is 3 mm (approximately 0.1 inches) in diameter.
Referring to FIG. 5, a circuit diagram associated with the electrical portion of focusing means 150 is shown. Light source 156 is attached at one end to a resistor 164 whose other end is coupled to the normally open contact of switch/relay 160. The common contact of the switch/relay 160 is in turn attached to the positive lead of power source 162. Finally, the second lead from light source 156 is coupled to the negative lead of power source 162 forming a complete circuit. In the one embodiment, switch 160 is a single pole single throw manual switch, power source 162 is a lithium battery part number BR-2/3AA manufactured by Panasonic, resistor 164 is a 500 ohm resistor, and light source 156 is a light emitting diode part number BL-B5131-L manufactured by American Bright Optoelectronics Co. Those ordinarily skilled in the art will recognize that the parts were selected to minimize the overall profile of the components, while providing a sufficiently long life and duty cycle upon energization of light source 156 to allow a user to perform a complete test. As such, other similar parts may be substituted as is known in the art without departing from the true spirit of the present invention. Alternatively, switch relay 160 may be a Bipolar or Field Effect transistor, or an SCR, or any other electronic switch as is known in the art. Power Source 162 may alternatively be a solar cell, or other power source as is known in the art.
In operation, upon depressing manual switch/relay 160, power source 162 provides a voltage source at the positive lead to light source 156. Resistor 164 current limits the power source 162 providing for a sufficient amount of current to drive the LED, while minimizing the drain on the power source 162. Light source 156 will illuminate for as long as the manual switch is actuated, allowing for the user to easily focus on the center of the grid portion. Upon deactivating the manual switch/relay 160, the light source is powered, thereby conserving the battery power.
In an alternative embodiment, light source 156 is configured to flash over the period of activation. This is accomplished, for example, by providing a flasher control circuit 168 (not shown) between power source 162 and light source 156. In one embodiment, the flasher control circuit may be implemented by the use of capacitors to cause a simple saw tooth waveform to be delivered to the light source thereby resulting in the flashing action. Alternatively, a timer circuit employing, for example, a 555 timer is implemented between manual switch 164 and light source 156 to effectuate the flashing. Alternatively, a flashing LED may be utilized which incorporates the control circuit into the LED package. Flashing LEDs are available off the shelf from the American Bright Optoelectronics Co.
In one embodiment, power source 162, resistor 164, and relay 160 are packaged within a single block 170 as shown in FIG. 4. The block 170 is attached to the surface of grid 100 and allows for the easy removal and replacement of battery 162. In one embodiment, block 170 is comprised of molded plastic, but may be made of any other similar material as is known in the art. In addition, block 170 is fashioned to extend a minimal height above the surface of grid area 110 to minimize the occurrence of knocks or bumps to the device.
Referring to FIG. 6, a cut away view of grid 100 is shown. In one embodiment, grid 100 is comprised of a top layer 500 having a first recess 502 for receiving light source 156 and aperture 504 for allowing interconnecting wires 506 to pass through top layer 500 for connection to power source 162 mounted in block 170. Top layer 500 includes an upper surface 510 which is made from a high contrast erasable, re-writable material which allows for the easy writing and recording of baseline information on the grid surface. The re-writable surface also allows for ease of erasing or correcting any mistakes made in the course of the diagnostic process. In use, this ease of correction feature has helped to encourage patients to map out affected portions of their vision which are abnormal, while non-erasable surfaces have been found to frustrate and even discourage patients from marking on the grid. As was disclosed above, ease of use coupled with patient comfort in recording baseline information have been found to be the keys to continued use of the test aid, and necessarily the early detection of degradations in the patient's vision. In one embodiment, upper surface 510 is comprised of vinyl. However, other materials which allow for ease of writing and erasing may be substituted as is known in the art.
Top layer 500 is disposed over a bottom layer 520 enclosing interconnecting wires 506 between the two layers. Bottom layer 520 includes a bottom surface 530 comprised of a magnetic material. The top layer is affixed to the bottom layer by any suitable glue material, such as an epoxy resin. In one embodiment, bottom layer 520 is a magnetic backed material composite part number 130 produced by Dowlng Miner Magnetics Corporation. The magnetic back material allows for the attachment of the grid to any metallic surface, such as on a refrigerator, which is located in a portion of the patient's house which is accessed daily. In addition, the magnetic back material allows the patient to quickly and easily store and locate the grid, while the re-writable/erasable surface allows for the preservation of the vital baseline information. In use, this type of easily accessible, conveniently storable and erasable configuration has been shown to encourage the patient to perform the self-diagnostic test on a daily basis.
Referring to FIG. 7, a second embodiment of the grid is shown. In this alternative embodiment, grid area 700 is comprised of a series of concentric circles 702 and radial lines 704. A focusing means 710 including light source 712 and diagonal centering lines 714 are include in this embodiment, and are similar to the focusing means disclosed above. In this embodiment, the attention centering function of focusing means 710 is augmented by the polar grid configuration due to the tunnel affect created by the concentric circles.
In operation, a patient will define a baseline characterization of his vision at his or her respective physicians's office in order to track the progress of this degenerative eye disorder. The baseline characterization is performed by marking on the re-writable/erasable surface of the grid the areas of distortion which have arisen in the particular person's vision as of a baseline time. Thereafter this baseline information may be readily compared to the present results so that the progress of the disease may be monitored.
In use, the grid is to be mounted to a metallic surface such as found on a common refrigerator door, in a well traveled location of the patient's home. The magnetic back mounting also minimizes the risk of misplacing the grid thereby losing the baseline information that has been developed and recorded on the grid device. The grid being adaptable for easy, convenient, and highly visible storage while not in use, will encourage the patient to repeat the test as necessary and to record all relevant information for discourse with a physician at the appropriate juncture. At the designated hour of a given day, the patient can quickly and easily locate the grid, and activate the light source to focus the patient's attention. The focusing means is activated by depressing the manual switch located on the casing. Thereafter, the patient may quickly and easily perform a test on each eye, comparing his or her current vision (and associated defects) against the baseline information stored on the grid. In the event any differences are detected over the baseline, the patient may document these new changes by marking on the grid the areas that have become affected and contact his or her respective physician.
The present invention has been described with reference to a few specific embodiments. The description is illustrative of the invention is not to be construed as limiting the invention. Various modifications may occur to those skilled in the art without departing from the true spirit and scope of the invention as defined by the pending claims. | An improved ophthalmological self test unit for assisting in the self evaluation of the degenerative effects of certain eye disorders. The self diagnostic ophthalmological device includes a grid area having a re-writable surface which is fixably attached to a magnetic backed material for ease of attachment to any metallic surface such as might often be found on a refrigerator. Disposed on the grid surface is a central focusing means for assisting in the focusing of a patient's attention to the central portion of the high contrast grid structure. In an alternative embodiment a polar grid is utilized along with the central focusing means mounted upon the magnetic backed material. | 0 |
BACKGROUND AND SUMMARY OF THE INVENTION
The invention relates to packaging and shipping systems and in particular to packaging of materials and items to be secured as a unit load or to be secured to a shipping and transporting means, such as a pallet. Specifically, it relates to such systems using plastics stretch film (a high cling film) as the binding and securing agent.
A need has existed for some time for a simple and economical means for manually applying plastics stretch film material. This invention provides that simple and economical means to do the work.
In the prior art two methods are available for applying the plastics stretch film material to materials and units to be packaged or secured as hereinbefore described.
One method is to use a very expensive automatic machine to hold a supply of the plastics stretch film and to automatically wrap it around the unit of materials to be packaged; and to secure the unit of materials to a shipping or transporting means. Such machines require the attention of an operator and they do have their own limitations.
Another method is to use a commercial manually operated grabbing or holding device. However, this manually operated device is very expensive in comparison to the cost of the present invention. The commercial device is difficult to adjust to obtain the wide range of speeds and tensions that are required while manually wrapping the plastics stretch film to a unit load. The adjusting system on the commercial unit is such that it is difficult to "feel" the fine line between "full stop" and "just barely moving." As a result, many broken films are encountered during use of the commercial unit. The present invention eliminates these problems and is extremely simple to operate.
One of the devices in the prior art consists of a shaft means passing through the tubular core of the roll of plastics film material. The shaft has more or less "D" shaped hand grips on each end that are held by the operator and used to pull the plastics film around or over the unit or load being packaged or secured. When more tension is to be placed on the plastics film, one of the two hand grips is twisted to tighten the shaft movement through the core of the roll of plastics film. This tightening by twisting one of the hand grips does not provide a sensitive "feel" in the operator's hands and is the cause of the frequent breaking of the plastics film mentioned hereinbefore.
Another of the devices in the prior art consists of a shaft means passing through the aforementioned tubular core of the roll of plastics film material. The shaft also has more or less "D" shaped hand grips on each end as hereinbefore described, but the tension adjustment is provided by a brake-nut on the end of the shaft. Changes in the need for more or for less tension requires the operator to use one hand to operate the brake-nut while holding the roll of plastics film with the other hand in one of the "D" shaped hand grips. This method of adjusting the tension is an awkward operation to perform. In addition, this method also causes frequent breaks of the plastics film.
In the present invention the control of the amount of tension is by the direct pressure or the squeeze of the operators hands on the flexible tube-like devices around extended ends of the core of the roll of plastics material. Two embodiments are provided for extending the core ends of the roll of the plastics material, however, the tension control means is the same in each case.
In the prior art the fixing of the device to a roll of plastics stretch film required considerable time and effort to insert a shaft through or to drive a toothed or spiked shaft into the ends of the core of the roll of plastics stretch film, and then add hand grips, holding or securing nuts, and other such mechanical operations. In the present invention, the preparation is primarily the slipping of two flexible hand grips on the ends of the core of the roll of plastics stretch film or on simple inserts in the core.
It is, therefore, an object of the invention to provide a system for manually applying plastics stretch film to a unit that is economical to manufacture and simple to operate.
It is another object of the invention to provide a system for manually applying plastics stretch film to a unit that permits the operator to "feel" the movement and tension condition through the hands on the device of the system.
It is yet another object of the invention to provide a system for manually applying plastics stretch film to a unit that consists of two simple flexible hand grips.
It is a further object of the invention to provide a system for manually applying plastics stretch film to a unit that does not require the operator to remove the hands from the device to change the tension setting.
Further objects and advantages of the invention will become apparent in light of the following description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictorial view of a first embodiment of flexible hand grips on extended core ends of a roll of plastics stretch film;
FIG. 2 is an exploded pictorial view of an extended length core for plastics stretch film and flexible hand grips;
FIG. 3 is a pictorial view of a second embodiment of flexible hand grips on core extensions of a roll of plastics stretch film;
FIG. 4 is a partial exploded pictorial view of the second embodiment of a flexible hand grip on a core extension of a roll of plastics stretch film.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings and particularly to FIGS. 1 and 3, a first embodiment of the system for plastics stretch film is seen at 10 in FIG. 1, and a second embodiment of the system for plastics stretch film is seen at 20 in FIG. 3.
In FIG. 1 a roll of plastics stretch film 12 is shown on a core 14. The direction of the core wrap of the roll of plastics stretch film 12 is shown by the arrow thereon, however, it is to be understood that the direction of the arrow on such a drawing could be reversed without changing the concept of this invention.
A pair of cylindrical flexible tube-like hand grips 16 are shown in FIG. 1 on the ends of said core 14 of said roll of plastics stretch film 12.
The inside diameter 18 of hand grips 16 is a close fit over the outside diameter of core 14, but with sufficient clearance so that the core 14 can turn easily within the hand grip 16.
In FIG. 2 the length of core 14 can be seen to be in one piece. The hand grips 16 are shown in an exploded view in relation to the core 14. The inside diameter 18 of hand grip 16 is shown in relation to the outside diameter of the core 14.
The extension of the core 14 on each side of the roll of plastics stretch film 12 for a distance on each side thereof that is slightly more than the length of the hand grip 16 is a part of this first embodiment of this invention. Thus, the extended length core 14, or in other words, the core 14 with extended ends, is an element of this invention.
It is to be noted that a hollow tube-like core is illustrated but it is to be understood that a solid rod-like core is within the scope and intent of this invention.
It is to be noted that the outside diameter of core 14 is smaller than the usual or normal diameter of prior art cores of rolls of plastics stretch film. The usual or normal diameter of prior art cores is shown as core 32 of the roll of plastics stretch film 22 in FIG. 3, which will be described hereinafter.
It is to be understood that the possible chance existence of a small diameter core for a roll of plastics stretch film in no way precludes the present invention. Cores for rolls of plastics stretch film are normally of a length approximating the width of the plastics stretch film wrapped thereon, and this invention includes the extension of the length of the core to provide extended ends as hereinbefore described for the first embodiment.
Turning now to the second embodiment of the system for plastics stretch film 20, the following description relates to FIGS. 3 and 4.
The second embodiment of the system for plastics stretch film 20 provides a means for using rolls of plastics stretch film 22 on core 32 where the length of the core 32 is approximately the same as the width of the roll of plastics stretch film 22. This second embodiment provides a means of using the roll of plastics stretch film 22 on a core 32 without the need for rerolling the plastics stretch film 22 off of a short length core such as core 32 on to a larger length core such as core 14 in FIGS. 1 and 2.
As noted hereinbefore, the usual or normal outside diameter of core 32 is larger than the outside diameter of core 14 of the first embodiment.
The second embodiment 20 provides a pair of adapters so that core 32 can be used with the same pair of hand grips 16 that are used in the first embodiment 10. In FIGS. 3 and 4 the hand grips 16 of the first embodiment 10 are shown as hand grips 26 for clarity when speaking of the second embodiment 20. Hand grips 16 of the first embodiment 10 and hand grips 26 of the second embodiment 20 are exactly alike and can be considered one and the same concept.
The aforementioned adapter is shown in FIGS. 3 and 4 at 30. It is to be noted that the adapter 30, one for each hand grip, may be constructed in two ways.
The first construction of adapter 30 is as a single washer-like plug. The outside diameter of adapter 30 is a very close and tight fit for the inside diameter 34 of core 32 of the roll of plastics stretch film 22. The outside surface of adapter 30 has a very slight taper in order to introduce it easily into the inside diameter 34 of core 32. A short length of core 24 (the size of core 24 being exactly the same as core 14 of the first embodiment as far as the diameter is concerned) is inserted into the inside diameter of the washer-like adapter 30 for a very tight friction held fit. This first construction is shown in FIGS. 3 and 4.
The second construction of adapter 30 is as a single piece unit where both the element 30 and the element 24 are of one-piece construction, the total being of the same overall configuration as the first construction, but not illustrated on the drawings. In this second construction the shape and taper of the element 30 for fitting the inside diameter 34 of core 32 are exactly the same as described for the first construction hereinbefore. In this second construction, the outside diameter of the element 24 is exactly the same as described for the first construction hereinbefore.
Hand grips 26 are placed on the adapter element 24 (either first or second construction) the same as hand grips 16 were placed on the extensions of core 14 in the first embodiment. The inside diameter 28 of hand grips 26 is a close fit over the outside diameter element 24, but with sufficient clearance so that element 24 can turn easily within the hand grip 26, the same as core 14 turns easily within hand grip 16 in the first embodiment.
As to the materials: the cores 14 and 32 are usually of cardboard-like or fiber material, but could be wood in rod-like configuration or could be any similar or suitable materials; the material of the adapter 30 may be wood, fiber, plastics or any similar or suitable material for the second construction or combination thereof for elements 30 and 24 of the first construction; the material for the hand grips 16 and 26 may be any flexible rubber-like material; flexible plastics type material, flexible paper or fiber-like material, or any similar or suitable material, as long as the material will be flexible when squeezed.
In operation, the user grips the hand grips 16 (for first embodiment) or 26 (for second embodiment) on the extension of core 14 or core extension 24, respectively, and gives a slight squeeze to the hand grips 16 (or 26) in order to "feel" the extension of core 14 (or core extension 24). In the description of the operation which follows, only the first embodiment 10 will be described, the description for the second embodiment 20 is exactly the same.
In case where the initial friction between the hand grips 16 or 26 and the cores 14 and 24 is too great to obtain a satisfactory "feel" or a free movement, a suitable lubricant, such as a light coating of powder or a wax may be used.
As the operator plays out the plastics stretch film 12 during the wrapping of a unit or the securing of unit to a transporting means, a sufficient grip is maintained on the hand grips 16 to provide the necessary control of tension on the plastics stretch film 12. This control of tension is gaged by the "feel" of the extension of core 14 through the soft flexible hand grips 16. The operator can make a full stop of the turning by a tight squeeze on hand grips 16 or the operator can have a free running play out of plastics stretch film 12 as the plastics stretch film unrolls by loosening the squeeze on hand grips 16. Varying of hand squeeze pressure on hand grips 16 permits the control of the play out of plastics stretch film 12 while also controlling how tightly the plastics stretch film 12 is pulled to provide the wrap or securing of the unit being packaged or secured. The squeezing of the hand grips 16 provides a braking action that has controlled instantaneous results.
The use of this system may be practiced by a manufacturer involving the plastics stretch film on cores as illustrated in this invention, or by a user rewinding the film on a core of his choosing from a supply unit.
As can be readily understood from the foregoing description of the invention, the present structure and system can be configured or operated in different modes or ways to provide the ability to use plastics stretch film to package a unit or to secure a unit to a transporting means.
Accordingly, modifications and variations to which the invention is susceptible may be practiced without departing from the scope and intent of the appended claims. | The invention is an improved apparatus for the manual application of plastics stretch films to materials and items to be packaged and secured as a unit or packaged and secured to a shipping and transporting means. The apparatus consists of an extended core for the supply of plastics stretch film and a pair of tubular-like grip means for said extended core. Said grip means serving as a manual control means for the speed of paying out the plastics stretch film material, and as a manual means for applying tension on the film during the course of applying it to materials and items. | 1 |
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