PNEUMATIC CONVEYOR

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0001] Not Applicable. BACKGROUND OF THE INVENTION

(1) Field of the Invention

[0002] The present invention relates to a differential impulse conveyor which uses bellows to provide the reciprocating motion for moving the objects along the conveyor.

(2) Description of the Related Art

[0003] Differential impulse conveyors, also known as linear motion conveyors, move objects along a tray or surface by varying the direction and rate of movement or speed of the tray. The conveyor motor moves the tray slowly at a slow speed in a forward direction to convey the objects forward. The conveyor motor then moves the tray quickly at an increased speed in the opposite or backward direction. As the tray is quickly moved in the backward direction, the objects slide along the tray such that the objects remain in the forward position. The slow forward and fast rearward motion is repeated to move the objects along the tray in the forward direction.

[0004] U.S. Patent Nos. 6,722,492, 6,880,693, 6,899,218 and 7,083,042 all to applicant, show pneumatic differential impulse conveyors which use bellows to move the conveying surface. The related art has also shown various types of differential impulse conveyors where the conveying surface is driven in the forward direction at a slow speed and is driven in the backward direction at an increased speed. Illustrative are U.S. Patent Nos. 6,794,757 to Svejkowsky et al.; 5,850,906 to Dean and 6,209,713 to Takahashi et al. The conveyors use a variety of different drive motors other than bellows.

[0005] U.S. Patent Nos. 1,146,947 to Norton; 2,214,755 to Tafel; 2,473,193 to Campion; and 4,508,208 to Preddy describe pneumatic transporters or conveyors which use pneumatic cylinders, pistons and seals to provide the drive or momentum for the conveyor. A fluid such as air can be used to move the pistons. However, none of the patents show the use of pneumatic bellows.

[0006] Also, of interest is U.S. Patent No. 2,378,979 to Burt which describes a vibrating conveyor which uses a pressure responsive element such as a bellow or flexible diaphragm to create vibrations which are transferred to a conveyor table.

[0007] There remains the need for a differential impulse conveyor which is compact and has a low profile and which uses bellows as the drive motor. Bellows have inherent qualities of low maintenance, tolerance to lateral misalignment, high resistance to contamination and frictionless stroke. Bellows are also capable of generating high forces and need no lubrication. The use of bellows enables the present invention to be inexpensive to construct and inexpensive to maintain.

BRIEF SUMMARY OF THE INVENTION

[0008] A differential impulse pneumatic conveyor using bellows to move a conveyor tray. The conveyor includes a conveyor motor having bellows, a drive block, and a fluid control system. The conveyor operates by expanding a first bellows which moves the drive block in a first direction. When the drive block reaches the predetermined travel distance, the drive block activates a limit switch which sends a first signal to the control valve to change the direction of travel of the drive block by supplying fluid to the second bellows. The second bellows expands and moves the drive block in the second direction. When the drive block reaches the predetermined travel distance in the second direction, the drive block activates the limit switch which sends a second signal to the control valve to change the flow of fluid back to the first bellows. A flow control valve is used to control the rate of flow of the signal from the limit switch to the control valve which controls the rate at which fluid is supplied to the bellows. The signal is controlled so that fluid is provided at a greater rate of flow to the second bellows so that the second bellows inflates at a faster rate than the first bellows which moves the conveyor plate at a greater rate of movement or speed in the second direction than in the first direction which moves the objects in the conveyor tray in the first direction.

[0009] The bellows are mounted by a support manifold to the housing of the conveyor. The support manifold has an inner passageway which connects a fluid inlet in the side of the support manifold to the fluid inlet of the bellows. The side feed of the support manifold allows for a more compact design. The drive block is slideably mounted on guide rods between the end plates and the bellows. In one (1) embodiment, the drive block is a single piece with recesses in each end. The bellows extend into the recesses and contact a center plate in the drive block to move the drive block. Recessing the bellows in the drive block reduces the overall length of the

conveyor while maintaining the amount and length of support provided to the conveyor plate by the drive block. Thus, the conveyor provides the same push force while having a more compact size. In another embodiment, the drive block includes two spaced apart drive plates which are rigidly secured together so that the drive plates act together as a single drive block. The use of two drive plates allows for mounting portions of the fluid control system between the drive plates which allows the conveyor to have a lower profile or less height while still providing the same push force.

[0010] The fluid control system includes a control valve, a limit switch and a flow control valve. In one (1) embodiment, all components of the fluid control system are fluid activated so that the switch and valves do not need seals and are more durable. The limit switch is a mechanically activated pneumatic switch. The limit switch includes a housing having a fluid inlet and two signal outlets. A spool extends between the ends of the housing. The spool is moveable along a length of the housing. The spool has a groove which forms a passageway between the fluid inlet and one of the signal outlets depending on the position of the spool. Movement of the spool between different positions along the length of the limit switch provides different signals. The drive block contacts the ends of the spool to move the spool to provide the signals. The signal outlets of the limit switch are in fluid communication with the signal inlets of the control valve. The signals from the limit switch activate the control valve and determine the action of the control valve. The control valve determines which bellows is provided with fluid. The flow control valve controls the rate of fluid flow of the signal from the limit switch to the control valve which in turn controls the rate at which fluid is provided to the bellows. [0011] The conveyor can be provided with a universal clamping system which enables a conveyor tray to be quickly and easily connected to the conveyor. The universal clamping system has pivotable arms and adjustable fasteners which enable the system to be used to secure conveyor trays having a variety of sizes.

[0012] The present invention relates to a conveyor motor for moving a conveyor plate to move objects along the conveyor plate, which comprises spaced apart first and second end plates with guide rods extending therebetween, first and second support manifolds mounted on the first and second end plates, first and second bellows mounted on the first and second support manifolds and spaced between the first and second end plates, a drive block having a pair of spaced apart first and second drive plates rigidly connected together and slideably mounted on the guide rods so that the first bellows is spaced between the first end plate and the drive block

and the second bellows is spaced between the second end plate and the drive block, and a fluid control system having only one limit switch connected to a control valve, wherein when the drive block moves in a second direction, the drive block contacts the limit switch which sends a signal to the control valve which sends fluid to the first bellows so that the first bellows expands and moves the drive block in a first direction, wherein as the drive block moves in the first direction, the drive block contacts the limit switch which sends a signal to the control valve which sends fluid to the second bellows so that the second bellows expands and moves the drive block in the second direction, wherein the control valve sends fluid to the first bellows at a first fluid flow rate so that the drive block moves at a first rate of movement in the first direction, wherein the control valve sends fluid to the second bellows at a second fluid flow rate so that the drive block moves at a second rate of movement in the second direction, and wherein the first rate of movement of the drive block in the first direction is greater than the second rate of movement of the drive block in the second direction.

[0013] Further, the present invention relates to a conveyor motor for moving a conveyor plate to move objects along the conveyor plate, which comprises spaced apart first and second end plates with guide rods extending therebetween, first and second support manifolds mounted on the first and second end plates, first and second bellows mounted on the first and second support manifolds and spaced between the first and second end plates, a drive block having opposed first and second ends with first and second recesses in the first and second ends respectively, wherein the first and second recesses are spaced apart by a center plate positioned between the recesses, wherein the first and second bellows extend into the first and second recesses, respectively and wherein, the drive block is slideably mounted on the guide rods, and a fluid control system having a single limit switch connected to a control valve, wherein when the drive block moves in a second direction, the drive block contacts the limit switch which sends a signal to the control valve which sends fluid to the first bellows so that the first bellows expands and moves the drive block in a first direction, wherein as the drive block moves in the first direction, the drive block contacts the limit switch which sends a signal to the control valve which sends fluid to the second bellows so that the second bellows expands and moves the drive block in the second direction, wherein the control valve sends fluid to the first bellows at a first fluid flow rate so that the drive block moves at a first rate of movement in the first direction, wherein the control valve sends fluid to the second bellows at a second fluid flow rate so that the drive block moves at a second rate of movement in the second direction, and wherein the first

rate of movement of the drive block in the first direction is greater than the second rate of movement of the drive block in the second direction.

[0014] Still further, the present invention relates to a conveyor for moving objects along a conveyor tray, which comprises spaced apart first and second end plates, first and second support manifolds mounted on the first and second end plates, first and second bellows mounted on the first and second support manifolds, guide rods extending between the spaced apart first and second end plates, a drive block having opposed first and second ends slideably mounted on the guide rods and spaced between the first and second bellows, a conveyor plate having opposed ends forming a plane of the conveyor plate and mounted on the drive block, a fluid control system having a limit switch and a control valve, wherein when the drive block moves in a second direction, the drive block contacts the limit switch which sends a signal to the control valve which sends fluid to the first bellows so that the first bellows expands and moves the drive block in a first direction, wherein the drive block contacts the limit switch which sends a signal to the control valve which sends fluid to the second bellows so that the second bellows expands and moves the drive block in the second direction, wherein the control valve sends fluid to the first bellows at a first fluid flow rate so that the drive block moves at a first rate of movement in the first direction, wherein the control valve sends fluid to the second bellows at a second fluid flow rate so that the drive block moves at a second rate of movement in the second direction, and wherein the first rate of movement of the drive block in the first direction is greater than the second rate of movement of the drive block in the second direction, and pivotable arms having opposed first and second ends with the first end pivotably connected to the conveyor plate and having an adjustable fastener mounted at the second end to removably mount the conveyor tray to the conveyor plate.

[0015] The substance and advantages of the present invention will become increasingly apparent by reference to the following drawings and the description.

BRIEF DESCRIPTION OF THE DRAWING(S)

[0016] Figure 1 is a perspective view of the conveyor 10 of one (1) embodiment of the present invention having a bar 104 and multiple conveyor trays 100.

[0017] Figure 2 is a top view without the conveyor plate 14 of one (1) embodiment of the conveyor 10, showing the drive block 32.

[0018] Figure 3 is a cross-sectional side view of the conveyor 10 showing the bellows 26 and

28 in the recesses 32E and 32F of the drive block 32.

[0019] Figure 4 is a partial exploded view of the drive block 32, bellows 26 and 28 and support manifolds 16 and 18 of one (1) embodiment of the invention.

[0020] Figure 5 is an exploded view of one (1) of the support manifolds 16 and bellows 26.

[0021] Figure 6 is a perspective view of one (1) of the support manifolds 16 and the bellows

26.

[0022] Figure 7 is a perspective view of the limit switch 54.

[0023] Figure 8 is an exploded view of the limit switch 54 showing the cover 68 removed.

[0024] Figure 9 is a cross-sectional view of the limit switch 54 in the neutral position.

[0025] Figure 10 is a cross-sectional view of the limit switch 54 in the first position.

[0026] Figure 11 is a cross-sectional view of the limit switch 54 in the second position.

[0027] Figure 12 is a schematic representation of the fluid flow system of the conveyor motor.

[0028] Figure 13 is a perspective view of the conveyor 10 of one (1) embodiment of the present invention having the universal clamping system.

[0029] Figure 14 is a top view of the conveyor 10 without the conveyor plate 14 of one (1) embodiment of the invention showing the limit switch 54 spaced between the drive plates 34A and 34B of the drive block 34.

[0030] Figure 15 is a side view of the conveyor 10 without the side wall 12C of the housing

12 of one (1) embodiment of the invention showing the drive block 34.

[0031] Figure 16 is a view of the drive block 34 of one (1) embodiment of the invention having the spaced apart drive plates 34A and 34B.

DETAILED DESCRIPTION OF THE INVENTION

[0032] All patents, patent applications, government publications, government regulations, and literature references cited in this specification are hereby incorporated herein by reference in their entirety. In case of conflict, the present description, including definitions, will control. [0033] A pneumatic conveyor 10 for moving objects 102 along a tray 100. The conveyor 10 includes a housing 12, a conveyor motor and a conveyor plate 14. In one (1) embodiment, the conveyor 10 also includes an adjustable clamping system for attaching the conveyor tray 100 to the conveyor plate 14 (Figure 13). U.S. Patent Nos. 6,722,492, 6,880,693, 6,899,218 and

7,083,042 all to applicant, disclose pneumatic conveyors having bellows 26 and 28 and are incorporated herein by reference in their entirety.

[0034] In one (1) embodiment, the housing 12 includes opposed end plates 12A and 12B, opposed side walls 12C, and a bottom wall 12D. The end plates 12A and 12B, side walls 12C and bottom wall 12D form a cavity or inner chamber within which is mounted the conveyor motor. The conveyor motor includes bellows 26 and 28, support manifolds 16 and 18, a drive block 32 or 34, and a fluid control system. The conveyor motor also includes guide rods 15 which extend between the end plates 12A and 12B. The guide rods 15 extend essentially parallel to the plane A formed by the conveyor plate 14. In one (1) embodiment, the conveyor motor includes a first pair of spaced apart, parallel guide rods 15 which are positioned adjacent the bottom wall 12D of the housing 12. In another embodiment, the conveyor motor includes a second pair of guide rods (not shown). The second pair of guide rods is spaced above the first pair of guide rods 15 adjacent the conveyor plate 14. The number of guide rods 15 depends on the size and push force of the conveyor motor. The larger the conveyor motor and the greater the push force, the larger the drive block 32 or 34 and the greater the number of guide rods 15. [0035] The support manifolds 16 and 18 are attached to the end plates 12A and 12B respectively and extend into the inner chamber formed by the housing 12. The support manifolds 16 and 18 are identical and therefore only one (1) will be described in detail. The support manifold 16 has opposed ends 16A and 16B with the first end 16A secured to the inner surface of the end plate 12A. In one (1) embodiment, the support manifold 16 is secured to the end plate 12A by a threaded bolt which extends through the end plate 12A into a threaded opening in the first end 16A of the support manifold 16. The support manifold 16 has a fluid inlet 20 spaced between the ends 16A and 16B of the support manifold 16. The fluid inlet 20 is connected by a passageway to the fluid outlet 24 in the second end 16B of the support manifold 16 (Figure 14) . In one ( 1 ) embodiment, the support manifold 16 is solid except for the passageway. The position of the fluid inlet 20 in the side of the support manifold 16 enables the entire conveyor motor to be positioned in the inner chamber formed by the housing 12. In one (1) embodiment, the support manifold 16 has a cylindrical shape. In one (1) embodiment, the circumference of the support manifold 16 is essentially the same as the circumference of the first end 26A of the bellow 26 to which the support manifold 16 is connected. In one (1) embodiment, the fluid outlet 24 is a female, threaded opening in the second end 16B of the support manifold 16.

[0036] The bellows 26 and 28 have opposed first and second ends 26A and 26B with a flexible membrane extending therebetween forming an inner cavity in the bellows 26 and 28. The bellows 26 and 28 are identical and therefore only one (1) will be described in detail. The first end 26 A of the bellows 26 A has a fluid inlet 30 which is in fluid communication with the inner cavity of the bellows 26. The fluid inlet 30 of the bellows 26 is a threaded male connector which engages the threaded fluid outlet 24 of the support manifold 16. The fluid inlet 30 has a center bore to allow fluid communication between the support manifold 16 and the bellows 26 (Figure 5). In one (1) embodiment, the second end 26B of the bellows 26 is flat to allow for applying an even force to the drive block 32 or 34. In one (1) embodiment, the bellows 26 is an air spring manufactured by Enidine, Incorporated. In one (1) embodiment, the conveyor motor has first and second bellows 26 and 28 mounted on first and second support manifolds 16 and 18 which are mounted on first and second ends plates 12A and 12B respectively. It is understood that the first bellows 26 and the second bellows 28 can be a single bellows or multiple bellows working together.

[0037] The drive block 32 or 34 is movably mounted in the inner chamber of the housing 12 spaced between the second ends 26B of the bellows 26 and 28. The drive block 32 or 34 is slideably mounted on the guide rods 15 extending between the end plates 12A and 12B of the housing 12. In one (1) embodiment where the drive block 32 or 34 is mounted on a pair of guide rods 15, the guide rods 15 are spaced an equal distance from the top and the bottom of the drive block 32 or 34 adjacent the sides of the drive block 32 or 34. The drive block 32 or 34 is spaced above the bottom wall 12D of the housing 12 and extends upward slightly above the top of the end plates 12A and 12B and side walls 12C of the housing 12. In one (1) embodiment, the drive block 32 is constructed from a single piece and has a first end 32A and a second end 32B with a top side 32C and a bottom side 32D extending therebetween (Figure 4). A recess 32E and 32F is provided in each of the ends 32A and 32B of the drive block 32. The depth of the recesses 32E and 32F is such that the first recess 32E in the first end 32A of the drive block 32 does not extend into the second recess 32F in the second end 32B. The recesses 32E and 32F are aligned so that the recesses 32E and 32F share an end wall or center wall 32G essentially at the center of the drive block 32. The recesses 32E and 32F have a shape and size similar to the shape and size of the second end 26B of the bellows 26 and 28. In one (1) embodiment, the width of the drive block 32 between the ends 32A and 32B and the depth of the recesses 32E and 32F is such that when the drive block 32 is moved in one (1) direction, the predetermined travel distance,

essentially all of the unexpanded bellows 26 or 28 is located in the recess 32E or 32F. Thus, when the drive block 32 is moved the predetermined travel distance in the first direction toward the second end plate 12B, the second bellows 28 is essentially completely within the second recess 32F in the second end 32B of the drive block 32.

[0038] In another embodiment, the drive block 34 includes spaced apart first and second drive plates 34A and 34B rigidly secured together (Figure 16). The drive plates 34A and 34B are secured together so that during use, the first and second drive plates 34A and 34B act as a single unit to move the conveyor plate 14. Connecting the drive plates 34A and 34B together eliminates the potential for flexing or twisting of drive plates 34A and 34B during use. In one (1) embodiment, the drive plates 34A and 34B are connected together by rods 34C which extend perpendicular to the drive plates 34A and 34B. The width of the drive block 34 in this embodiment is such that when both of the bellows 26 and 28 are uninflated, the drive block 34 can be positioned between the bellows 26 and 28 without touching either of the bellows 26 and 28. Bumpers 36 are provided on the end plates 12A and 12B of the housing 12 and extend inward toward the drive block 32 or 34. The bumpers 36 prevent the drive block 32 or 34 from traveling beyond the predetermined travel distance.

[0039] The fluid control system controls the flow of fluid to the bellows 26 and 28 to control the movement and the rate of movement of the drive block 32 or 34 and thus the conveyor plate 14 and conveyor tray 100. In one (1) embodiment, the fluid is air. In one (1) embodiment, the fluid control system includes a control valve 40, a limit switch 54 and a flow control valve 69. The control valve 40 controls the flow of fluid to the bellows 26 and 28 in response to a signal from the limit switch 54. The limit switch 54 is activated through physical contact with the drive block 32 or 34. The flow control valve 69 regulates the speed of the signal from the limit switch 54 to the control valve 40 to control the rate at which the control valve 40 receives the signal and sends fluid to the bellows 26 and 28 once the limit switch 54 is activated by the drive block 32 or 34.

[0040] The control valve 40 has a fluid inlet 42, two (2) fluid outlets 44 and 46 and two (2) signal inlets 48 and 50. The fluid inlet 42 is connected to and in fluid communication with the fluid source (not shown). The two (2) fluid outlets 44 and 46 are connected to and in fluid communication with the fluid inlets 20 of each of the support manifolds 16 and 18. The two (2) signal inlets 48 and 50 are connected to and in fluid communication with the two (2) signal outlets 60 and 62 of the limit switch 54. In one (1) embodiment, the control valve 40 also has a

secondary fluid outlet 52 which is connected to the fluid inlet 58 of the limit switch 54 and allows for fluid to pass through the control valve 40 from the fluid source to the fluid inlet 58 of the limit switch 54.

[0041] The limit switch 54 is a mechanically activated sealless limit valve. The limit switch 54 includes a housing 56 having a fluid inlet 58, two (2) signal outlets 60 and 62, and a slideable spool 64 extending between and beyond the ends 56A and 56B of the housing 56. The spool 64 is slideably positioned in a bore in the housing 56 of the limit switch 54. The fluid inlet 58 is connected to a passageway which leads to the bore of the limit switch 54 within which the spool 64 is moveably positioned (Figures 9 to 11). Similarly, the first and second signal outlets 60 and 62 are connected by passageways to the bore having the spool 64. The passageways are in fluid communication with the bore. The spool 64 is slideably mounted in the bore of the housing 56 and is able to slide along the longitudinal axis A-A of the limit switch 54 between the ends 56A and 56B of the housing 56. The spool 64 is of such a length that both the first and second ends 64A and 64B of the spool 64 always extend beyond the first and second ends 56A and 56B of the housing 56 of the limit switch 54. The spool 64 has a groove 64C which allows for fluid communication between the fluid inlet 58 and the signal outlets 60 and 62 when the spool 64 is in a set position. In one (1) embodiment, the spool 64 has multiple grooves. In one (1) embodiment, the spool 64 has a first groove which aligns with the passageway of the fluid inlet 58 and the passageway of the first signal outlet 60 when the spool 64 is in a first position and a second groove which aligns with the passageway of the fluid inlet 58 and the passageway of the second signal outlet 62 when the spool 64 is in the second position. In one (1) embodiment, end caps 66 are placed on the ends 64 A and 64B of the spool 64. The end caps 66 prevent the ends 64A and 64B of the spool 64 from extending into the bore. In one (1) embodiment, the limit switch 54 has a cover 68 which extends over the ends 56A and 56B of the housing 56 of the limit switch 54 (Figure7). The cover 68 has stop plates 68A and 68B which are spaced apart from the ends 56A and 56B of the housing 56 of the limit switch 54. The stop plates 68A and 68B limit the movement of the spool 64. The stop plates 68A and 68B are positioned so that when the spool 64 is moved to the predetermined extended position in one (1) direction, the end cap 66 on the end 64A or 64B of the spool 64 contacts the stop plate 68 A or 68B and stops the spool 64 from extending further. The stop plates 68A and 68B do not prevent the switching posts 35 or 37 of the drive block 32 or 34 from contacting the ends 64A and 64B of the spool 64. The stop plates 68A and 68B are positioned so that when the spool 64 is extended to the predetermined

position and contacts the stop plate 68A or 68B, the spool 64 is either in the first position or the second position so that the groove 64C in the spool 64 is aligned with the passageway of the fluid inlet 58 and one (1) of the passageways of the signal outlets 60 and 62 (Figures 10 and 11). The limit switch 54 provides a first signal to the control valve 40 when the spool 64 is moved until the spool 64 contacts the first stop plate 68A and provides a second signal to the control valve 40 when the spool 64 is moved in the other direction until the spool 64 contacts the second stop plate 68B.

[0042] The signal outlets 60 and 62 of the limit switch 54 are connected by fluid lines to the signal inlets 48 and 50 of the control valve 40. A flow control valve 69 is located in the fluid line connecting one (1) of the signal outlets 60 and 62 of the limit switch 54 to one of the signal inlets 48 and 50 of the control valve 40. The flow control valve 69 allows for adjusting the rate of fluid flow from the limit switch 54 to the control valve 40. Thus, the flow control valve 69 controls how quickly the signal from the limit switch 54 is received by the control valve 40. In one (1) embodiment, a second flow control valve (not shown) is provided in the fluid line between the remaining signal outlet 60 or 62 and the corresponding signal inlet 48 or 50. The second flow control valve allows for controlling of the rate of movement of the conveyor plate 14 in both directions.

[0043] In one (1) embodiment where the drive block 32 is a single block, the control valve 40 and the limit switch 54 are mounted on the bottom wall 12D of the housing 12 spaced below the drive block 32. It is understood that the control valve 40 can be positioned in any convenient space in the inner chamber of the housing 12. The limit switch 54 is positioned so that when the drive block 32 is in the neutral, at rest position, centered between the uninflated bellows 26 and 28, the ends 64A and 64B of the spool 64 of the limit switch 54 are spaced an even distance from the ends 32A and 32B of the drive block 32 or 34 when the spool 64 is centered in the housing 56 of the limit switch 54. The limit switch 54 is positioned on the bottom wall 12D of the housing 12 so that when the drive block 32 is in the at rest, neutral position, the limit switch 54 is directly below the drive block 32 and is evenly spaced between the ends 32A and 32B of the drive block 32. In this embodiment, the ends 32A and 32B of the drive block 32 are provided with switching posts 35 which extend beneath the bottom side 32D of the drive block 32 toward the limit switch 54. In one (1) embodiment, the switching posts 35 are mounted on the ends 32A and 32B of the drive block 32 and have an extension which extends underneath the drive block 32 toward the limit switch 54 (Figure 3). In another embodiment, the switching posts 35 are

mounted on the bottom side 32D of the drive block 32 and extend inward toward the limit switch 54. In the embodiment where the drive block 34 includes two (2) spaced apart drive plates 34A and 34B, the control valve 40 and the limit switch 54 are positioned between the drive plates 34A and 34B. In one (1) embodiment, the limit switch 54 is mounted directly on top of the control valve 40 which is mounted on the bottom wall 12D of the housing 12 (Figurel5). It is understood that the control valve 40 can be positioned at the variety of locations within the inner chamber of the housing 56. The limit switch 54 is positioned between the drive plates 34A and 34B of the drive block 34 so that when the drive block 34 is in the neutral position, the limit switch 54 is equally spaced between the drive plates 34A and 34B. In one (1) embodiment, the switching posts 37 are provided on the inner surface of the drive plates 34A and 34B of the drive block 34 adjacent the limit switch 54 (Figure 14). The switching posts 37 extend inward toward the limit switch 54.

[0044] The conveyor plate 14 is secured to the top surface or side 32C of the drive block 32 or 34. The drive block 32 or 34 extends above the housing 12 so that during use, the conveyor plate 14 does not contact the housing 12. In one (1) embodiment, the conveyor 10 is able to mount on a plurality of trays 100 (Figure 1). In this embodiment, a bar 104 is connected to the conveyor plate 14 of the conveyor 10. The bar 104 extends outward on either side of the conveyor plate 14. The bar 104 extends perpendicular to the direction of movement of the conveyor plate 14. Multiple trays 100 can be secured along the length of the bar 104. [0045] In one (1) embodiment, the conveyor 10 is used to move objects 102 along a single tray 100 connected to the conveyor plate 14 of the conveyor 10 (Figure 13). In this embodiment, a universal clamping system is used to quickly and easily attach the tray 100 to the conveyor 10. The universal clamping system can be adjusted to accommodate trays 100 having a variety of sizes. In one (1) embodiment, the clamping system includes a plurality of pivotable arms 70 connected to the conveyor plate 14 of the conveyor 10. In one (1) embodiment, the pivotable arms 70 have a first end 7OA and a second end 7OB with an essentially flat top surface 7OC extending therebetween. The first end 7OA of the pivotable arms 70 is pivotably connected to the conveyor plate 14. A fastener 72 is mounted on the second end 7OB of the arms 70. In one (1) embodiment, the universal clamping system has two (2) pivotable arms 70 with the first arm pivotably mounted on the conveyor plate 14 adjacent the first end plate 12A and adjacent one (1) 12C side of the housing 12 and the second pivotable arm 70 pivotably mounted on the conveyor plate 14 adjacent the second end plate 12B and adjacent the other side 12C of the housing 12. In

one (1) embodiment, the universal clamping system has four (4) arms 70 and the arms 70 are pivotably attached adjacent each of the corners of the conveyor plate 14 such that a first pivotable arm 70 is pivotably connected adjacent the first end plate and first side of the conveyor plate 14, a second pivotable arm 70 is pivotably connected adjacent the second end plate 12B and the second side of the conveyor plate 14, a third pivotable arm 70 is pivotably connected adjacent the first end plate 12A and the second side of the conveyor plate 14, and a fourth pivotable arm 70 is pivotably connected adjacent the second end plate 12B and first side of the conveyor plate 14. In one (1) embodiment, the pivotable arms 70 are mounted on the conveyor plate 14 so that a plane B formed by the top surface 7OC of the pivotable arms 70 is essentially parallel to a plane A formed by the conveyor plate 14 (Figure 13). In one (1) embodiment, the pivotable arms 70 are mounted on a first or top surface of the conveyor plate 14 opposite the drive block 32 or 34 so that the conveyor tray 100 is spaced above the conveyor plate 14. In one (1) embodiment, a support bracket 74 having a pair of spaced apart pivotable arms 70 pivotably connected together at one end and having fasteners 72 at the other end is positioned spaced apart from the end of the conveyor 10 to provide additional support for the tray 100 (Figure 13). To secure the tray 100 using the universal clamping system, the conveyor tray 100 is placed on the top surface 7OC of the arms 70 above the conveyor plate 14. Next, the arms 70 are pivoted inward toward the sides of the tray 100. The fasteners 72 are loosened and raised and positioned over the sides of the tray 100. The fasteners 72 are then tightened to clamp the tray 100 between the fastener 72 and the top surface 7OC of the arms 70. The ability to pivot the arms 70 away from and toward the conveyor plate 14 allows for the mounting of trays 100 having a variety of widths and a variety of lengths. In one (1) embodiment, the fasteners 72 are vertically adjustable so that the distance between the top surface 7OC of the arms 70 and the fastener 72 can be adjusted to accommodate trays 100 have sides of different heights. In one (1) embodiment, the sides of the tray 100 have a thickness and the fasteners 72 have a groove which fits over the top of the sides of the tray 100 to clamp the tray 100 in position.

[0046] To operate the conveyor 10, the conveyor plate 14 is secured to the top side of the drive block 32 or 34 and the conveyor tray or tray s 100 are connected to the conveyor plate 14. In one (1) embodiment, where there are multiple trays 100, the bar 104 is connected to the conveyor plate 14 and the conveyor trays 100 are connected to the bar 104. In another embodiment, where the conveyor 10 has a single tray 100, the universal clamping system is attached to the conveyor plate 14 and the tray 100 is positioned between the pivotable arms 70.

The arms 70 are pivoted into position along the sides of the tray 100. The fasteners 72 are then adjusted over the sides of the tray 100 to clamp the tray 100 between the fasteners 72 and the top surface 7OC of the arms 70. In both embodiments, the conveyor tray 100 moves simultaneously with the conveyor plate 14.

[0047] The fluid source or air supply is connected to the fluid inlet 42 of the control valve 40. As the fluid flows into the control valve 40, the control valve 40 provides fluid to the first bellows 26. However, it is understood that in the initial, at rest neutral position, both of the bellows 26 and 28 are uninflated and which bellows 26 and 28 is inflated first depends on the state of the control valve 40. As fluid flows from the control valve 40 to the first bellows 26, the first bellows 26 expands. As the first bellows 26 expands, the first bellows 26 moves in the first direction and contact the center wall 32G or the first drive plate 34A of the drive block 32 or 34. In the embodiment where the bellows 26 and 28 are positioned in recesses 32E and 32F in the drive block 32 or 34, the second end 26B of the first bellows 26 contacts the center wall 32G at the end of the first recess 32E. As the first bellows 26 continues to expand, the drive block 32 or 34 moves in the first or forward direction toward the second end plate 12B and the second bellows 28. When the first bellows 26 reaches a partially expanded position and the drive block 32 or 34 has moved a portion of the predetermined distance in the first direction, the first switching post 35 or 37 adjacent the first side 32A or first drive plate 34A of the drive block 32 or 34 contacts the first end 64A of the spool 64 of the limit switch 54 and moves the spool 64 in a first direction toward the second end 56B of the limit switch 54. The first bellows 26 continues to expand and move the drive block 32 or 34 until the drive block 32 or 34 has moved the predetermined travel distance in the first direction. It is understood that upon reaching the predetermined travel distance, the first bellows 26 can be partially or fully inflated. When the drive block 32 or 34 has moved the predetermined distance, the spool 64 has been moved to the first position so that the groove 64C in the spool 64 is positioned to provide a fluid path between the fluid inlet 58 and the first signal outlet 60 of the limit switch 54. In one (1) embodiment, the second end 64B of the spool 64 contacts a second stop plate 68B provided adjacent the second end 56B of the housing 56 of the limit switch 54 to ensure that the spool 64 stops at the correct position. The fluid from the fluid inlet 58 travels through the passageway, through the groove 64C in the spool 64, and through the passageway to the first signal outlet 60. The signal travels from the first signal outlet 60 through the fluid line to the first signal inlet 48 of the control valve 40. The first signal tells the control valve 40 to switch the flow of fluid and send the fluid to the

second bellows 28. As fluid flows from the control valve 40 to the second bellows 28, the second bellows 28 expands and pushes on the drive block 32 or 34. The drive block 32 or 34 pushes on the first bellows 26, forcing the fluid out of the first bellows 26. In one (1) embodiment, an exhaust valve (not shown) is provided to allow for controlling the fluid escaping the first bellows 26. In another embodiment, the fluid escapes the bellows 26 through the fluid inlet 30. As the second bellows 28 continues to expand, the second switching post 35 or 37 adjacent the second end 32B of the drive block 32 or the second drive plate 34B of the drive block 34 contacts the second end 64B of the spool 64 of the limit switch 54 and moves the spool 64 in the second direction toward the first end plate 12A. When the drive block 32 or 34 moves the predetermined distance in the second direction and is at the predetermined travel distance in the second direction, the spool 64 has been moved to the second position so that the groove 64C in the spool 64 is positioned to provide a fluid path between the fluid inlet 58 of the limit switch 54 and the second signal outlet 62. It is understood that the spool 64 may have multiple grooves 64C and that different grooves 64C may be used to form the first passageway between the fluid inlet 58 and the first signal output 60 and the second passageway between the fluid inlet 58 and the second signal output 62. The second signal is sent and received at the second signal inlet 50 of the control valve 40. The second signal tells the control valve 40 to stop the supply of fluid to the second bellows 28 and to provide fluid to the first bellows 26. In one (1) embodiment, the maximum predetermined distance traveled by the drive block 32 or 34 in the first direction is the same as the maximum predetermined distance traveled by the drive block 32 or 34 in the second direction.

[0048] The flow control valve 69 is positioned in the fluid line between the second signal output 62 of the limit switch 54 and the second signal inlet 50 of the control valve 40. The flow control valve 69 controls the rate of flow of the signal to the second signal inlet 50 of the control valve 40. In one (1) embodiment, the flow control valve 69 reduces the rate of flow of the signal so that the second signal travels between the limit switch 54 and the control valve 40 at a rate of flow or speed less than the speed of travel of the first signal. In one (1) embodiment, the flow control valve 69 slows down the rate of switching of the fluid flow from the second bellows 28 to the first bellows 26. The reduction of the rate of flow of the second signal to the control valve 40 causes a slow down in the switching of the fluid flow from the second bellows 28 to the first bellows 26 and causes a momentary pause in the movement of the drive block 32 or 34. Thus, the transition of the drive block 32 or 34 from moving in the second direction toward the first

bellows 26 to moving in the first direction toward the second bellows 28 is not instantaneous. The pause in the movement of the drive block 32 or 34 allows for the conveyor tray 100 to reestablish a factional connection with the items or objects 102 on the conveyor tray 100. The flow control valve 69 also reduces the rate at which the control valve 40 sends fluid to the first bellows 26. The flow control valve 69 allows a predetermined rate of flow of fluid to the first bellows 26. In one (1) embodiment, the rate of the flow of fluid or the speed of the fluid flow to the first bellows 26 begins slow and gradually reaches its full speed. This gradual increase in fluid flow results in a gradual acceleration of the drive block 32 or 34 in the first direction which is slower than the acceleration of the drive block 32 or 34 in the second direction. The quick expansion or inflation of the second bellows 28 causes the drive block 32 or 34 to move quickly at a faster rate of movement or speed in the second, rearward direction while the gradual, slower expansion or inflation of the first bellows 26 causes the drive block 32 or 34 to move more slowly at a slower rate of movement or speed in the first, forward direction. The uneven bidirectional movement of the drive block 32 or 34 and thus the conveyor plate 14 causes the objects 102 or items on the conveyor tray 100 to move in the first direction. It is understood that the position of the flow control valve 69 can be changed to switch the direction of movement of the objects 102.

[0049] It is intended that the foregoing description be only illustrative of the present invention and that the present invention be limited only by the hereinafter appended claims.