Abstract:
An automatic cassette wrapping machine includes three interconnected stations: a station for loading cassettes and inserting cassettes into an assembly line; a station for receiving the cassettes and engaging the cassettes with paperboard sheaths having preapplied glue; and a station for receiving the sheath encased cassettes and stacking the cassettes in shippable pluralities. The cassette assembly machine is fully automated and includes a central processing unit receiving signals from sensors positioned throughout the machine to coordinate all aspects of machine operation.

Description:
This patent application is being filed as a conversion of provisional application Ser. No. 60/087,257 filed May 29, 1998 and provisional application Ser. No. 60/122,441 filed Mar. 2, 1999. All disclosures and information contained in both provisional applications are expressly incorporated herein. 
    
    
     The present invention relates to an automatic cassette wrapping and assembly machine for use in manufacturing video cassettes, including but not limited to the type disclosed in U.S. Pat. No. 5,311,388. For the purposes of this patent application and description, the invention will be described for the wrapping and assembly of VHS-type tape cassettes. However, the description is not intended to be limiting upon the scope of the claims which are appended hereto. 
     It has long been an objective in the audio and video duplication industry to provide for the enhanced manufacture and assembly of cassettes, tapes and their labeling and packaging. Commonly, such cassettes and tapes receive labeling which is adhered directly to the cassette or tape body and the labeled cassette or tape is then placed in corrugated packaging having labeling and graphics applied thereto. Need for the corrugated sheath or container for such cassettes and tapes has been eliminated by cassettes of the type shown in U.S. Pat. No. 5,311,388. Cassettes or tapes of the type shown in the &#39;388 patent have a sheath or label which is applied to the outer surfaces of the cassette or tape which include the complete graphics and labeling, thereby eliminating the need for the outside cover. The cassette of the &#39;388 patent is simply labeled and wrapped in clear wrap to seal its surfaces prior to shipping. Such cassettes, to date, are time-consuming in their manufacture and use as the outer sheath or label is usually hand applied. Thus, there is a need for an automatic cassette wrapping and assembly machine which performs the steps of applying the sheath to the cassette in a rapid, repetitive automated fashion. 
     SUMMARY OF THE INVENTION 
     The present invention provides an automatic cassette wrapping and assembly machine generally composed of three stations: a station for loading cassettes and inserting cassettes into the assembly line; a sheath assembly and wrapping station; and a discharge and stacking station. 
     The loading and insertion station includes a magazine in which the cassettes are loaded and stacked. The magazine described herein has a capacity to retain rows of 60 units with a capacity of ten rows, thus providing for 600 cassettes in a fully loaded magazine. However, magazine capacity may be designed to meet demand. The machine, as described herein, is designed to process a minimum of 60 cassettes per minute, thereby a fully loaded magazine provides a ten minute operative capacity. A lowering and insertion member is designed to support the rows of stacked cassettes and insert one row at a time onto a feed conveyor member which transports the row of cassettes to the assembly station. The feed conveyor member is provided with a continuous belt and includes a guide member which prevents the row of cassettes from slipping out of position. The conveyor member is driven by stepper motors which receive drive inputs from a central processing unit, the inputs being regulated by sensing devices positioned to determine the relative positioning of cassette members throughout the machine. The sensors monitor the flow of cassettes on the conveyor and are used to signal when the conveyor is clear for insertion of another row of cassettes. Other sensors are used to monitor for the proper orientation and positioning of the cassettes as they approach the assembly station. 
     The assembly station is comprised of a flight conveyor which receives the cassettes from the feed conveyor and lifts the cassettes vertically into a compression conveyor. A sheath prefold and glue applicator apparatus operates in cooperation with the flight conveyor and compression conveyor. The flight conveyor includes a series of lift members driven by motors, preferably stepper motors programmed to move the distance of one cassette at a time, which carry a single cassette into an aligning track and into the compression conveyor. The compression conveyor receives the cassette which has engaged with a sheath having preapplied glue positioned at the mouth of the compression conveyor. As the cassette and sheath move through the compression conveyor, the pre-glued sheath is compressed and wrapped around the cassette. Sensors monitor the positioning of the cassettes and sheath and provide information signals to the central processing unit related to the cassette positioning on the flight conveyor; cassette positioning in the compression conveyor; sheath positioning and orientation; and cassette engagement with the sheath. 
     As the cassettes are approaching the flight conveyor and being positioned through engagement with the flight conveyor and aligning track, the sheath prefold and glue application apparatus is feeding sheath members with preapplied glue into position proximate the entrance to the compression conveyor for engagement with each approaching cassette. Individual sheaths are removed from a stack and each sheath is prefolded along scored lines and then straightened. The prefolded and straightened sheath receives an application of glue and is driven into its final position at the entrance to the compression conveyor. Again, sensors are positioned in the sheath transfer and glue application system to ensure proper positioning of the sheath with respect to the oncoming cassette, positioning of the sheath through the prefolding, straightening and gluing steps and for providing signals regarding the presence of defective and improperly positioned sheaths. After a sheath is positioned at the mouth of the compression conveyor, a cassette will be fed into the compression conveyor by the flight conveyor, first engaging the sheath along the spine of the cassette and then pressing the top flap, bottom flaps and end flaps of the sheath into engagement with the top surface, bottom surface and ends of the cassette respectively as the cassette and sheath move through the compression conveyor. It is envisioned that a quality control sensor to monitor the precise sheath wrap position on each finished cassette as the cassette exits the compression conveyor. As the cassette wrapped in the sheath exits the compression conveyor, it is guided onto a horizontally oriented compression chute having spaced rows of resilient fins designed to provide continuous pressure to the spine and ends of the sheath, thereby providing constant compression allowing the sheath and glue to set in position, thereby permanently bonding the sheath to the cassette. 
     As the cassette exits the compression chute, it is flipped to a horizontally oriented position onto a positioning conveyor which relays the cassette to the stacking station. The stacking station includes a bin having a vertically moving floor and an aligning and orienting apparatus located at the top of the bin. The aligning and orienting apparatus receives the cassettes from the positioning conveyor and orients them in rows of a preset number. As each row of cassettes becomes filled, a release mechanism is activated to drop the row of cassettes onto the floor of the stacking bin which is positioned immediately under the aligning and orienting apparatus. After each row of cassettes is deposited onto the floor of the stacking bin, sensors signal the central processing unit to activate a lift mechanism to lower the floor of the bin one cassette level to allow the next row of cassettes to be received from the aligning end orienting apparatus. After the bin is full, the stack of cassettes is ejected into an appropriate container and the floor of the bin is raised back to its starting position. 
     The present invention can be further appreciated by reference to the following description of the preferred embodiment of the invention with reference to the accompanying drawings. While the current embodiment, as described, dictates the use of specific types of drive mechanisms, motors and rollers, it is fully envisioned that the substitution of equivalent structure for the pneumatic lifts, stepper motors, servo motors, drive motors, compression rollers, conveyor belts, lift members, chain drives, gear and sprocket drives and sensors may be substituted without departing from the scope and overall vision of this invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the cassette wrapping and assembly machine of the present invention. 
     FIG. 2 is a front view, partially in ghost, of the cassette magazine and feed conveyor. 
     FIG. 3 is a side view of the cassette loading and insertion magazine showing the cassettes supported in an upraised position. 
     FIG. 4 is a side view of the cassette loading and insertion magazine showing the cassettes lowered to a position for placement on the feed conveyor. 
     FIG. 5 is a side view of the cassette loading and insertion magazine showing the positioning of the insertion member for placing the cassette row on the feed conveyor. 
     FIG. 5A is a side view of the cassette loading and insertion magazine showing the first row of cassettes partially inserted to the feed conveyor, while the next row of cassettes is supported by the insertion member. 
     FIG. 6 is a side view of the cassette loading and insertion magazine showing the insertion member fully extended to place a row of cassettes on the feed conveyor. 
     FIG. 7A is a partial side view of the front portion of the sheath prefold and glue application apparatus. 
     FIG. 7B is a partial side view of the remaining portion of the sheath prefold and glue application apparatus. 
     FIG. 8A is a partial cutaway side view of the cassette flight conveyor and compression conveyor and horizontally oriented feed and compression conveyor. 
     FIG. 8B is a partial cutaway side view of the continuation of the horizontally oriented feed and compression conveyor, positioning conveyor and stacking station. 
     FIG. 9 is an end view showing the stacking station of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, the automatic cassette wrapping and assembly machine of the present invention includes the following components. A cassette loading and insertion apparatus  10  is positioned to retain stacked rows of cassettes for placement, one row at a time, onto the feed conveyor  20 . The magazine  11  of the cassette loading and insertion apparatus  10  will provide capacity for ten stacked rows of VHS cassettes, each row containing sixty units. Thus, a fully loaded magazine  11  will contain 600 cassettes. All surfaces of the cassette loading and insertion apparatus  10  are preferably constructed of a hard canvas-based phenolic sheet chosen for its strong wear characteristics and its ability to provide a smooth non-abrasive surface on which the cassettes may slide, thereby preventing marking and any undesirable damage to the plastic cassette cases. It should be noted that all non-functioning and non-moving parts of the machine are preferably constructed of the same canvas-based phenolic sheet. 
     The feed conveyor  20  extends the length of the cassette loading and insertion apparatus  10  as shown in FIG.  2  and feeds to the assembly station  30  as shown in FIG.  8 A. 
     Referring back to FIG. 1, the assembly station  30  includes a flight conveyor  27 , shown in FIG. 8A, a compression conveyor  28 , shown in FIG. 8A, and a sheath prefold and glue applicator apparatus  50  positioned adjacent the flight conveyor  27  and the compression conveyor  28  as shown in FIGS. 1 and 8B. Finally, as shown in FIGS. 1,  8 B and  9 , a compression chute  57  is positioned downstream of the compression conveyor  28  and combines with a positioning conveyor  60  to feed the fully assembled cassettes to the stacking station  61 . The operation of the automatic cassette wrapping and assembly machine is controlled by a central processing unit  100 . 
     Referring now to FIG. 2, the magazine  11  of the cassette loading and insertion station  10  is formed to have opposed sidewalls  12  and a backwall  13 . The backwall  13  includes a slot  14  which runs the length of the backwall  13  and is slightly higher than the width of a standard VHS cassette, as shown in FIGS. 3-6. A lowering and insertion member  15  built for movement in the vertical and horizontal directions serves as the primary support for the vertically stacked rows of cassettes. The lowering and insertion member  15  includes a vertical elevator  16  which is raised and lowered by a pneumatic piston  17 . A horizontally actuated support and insertion platform  18 , driven by a pneumatic piston  19  is carried by the vertical elevator  16 . The non-functional surfaces of the insertion and support platform  18  are constructed of the same canvas-based phenolic sheet to ensure a smooth non-abrasive surface on which the cassettes may slide. A lip member  21  is located across the bottom of the open front of the magazine  11  and is designed to engage the bottom most row of cassettes, thereby ensuring that all the cassettes are properly aligned when being lowered by the lowering and insertion member  15  for insertion onto the feed conveyor  20 . 
     Referring now to FIGS. 3-6, the operation of the cassette loading and insertion station  10  can be ascertained. FIG. 3 shows the cassette loading and insertion station  10  at its start position, wherein the rows of cassettes which are stacked in the magazine  11  are supported by the top surface of the support and insertion platform  18 . A row of cassettes is shown in position on the feed conveyor  20  which are being fed to the assembly station  30 . The insertion and support platform  18  is then vertically lowered by means of the elevator  16  and its piston  17  as shown in FIG. 4, thereby lowering the stacked rows of cassettes to now rest in position on the magazine floor  22 . As the bottom row of cassettes engage and is supported by the floor  22  of the magazine, it aligns with the slot  14  in the back wall  13  of the magazine  11 . The magazine floor  22  is supported by a piston  23  which activates to move the floor vertically an approximate distance of ¼ to ½ inch. After the cassettes are in a position of support on the magazine floor  22  as shown in FIG. 4, the insertion and support platform  18  is withdrawn from engagement with the bottom row of cassettes by its piston  19  and is vertically raised by the elevator  16  and piston  17  to be positioned immediately behind the bottom row of cassettes as shown in FIG.  5 . The central processing unit, when signalled by the appropriate sensors (not shown) that the feed conveyor  20  is vacant, will activate the piston  19  to horizontally displace the insertion and support platform  18  to begin pushing the bottom row of cassettes through the slot  14 . As shown in FIG. 5A, the insertion and support platform  18  pushes the bottom row of cassettes through the slot  14 , and will begin supporting the immediately adjacent next row of cassettes on its top surface. As the next row of cassettes engage the top surface of the insertion and support platform  18 , the central processing unit activates the piston  23  supporting the magazine floor  22  to lower the magazine floor  22  approximately ¼ to ½ inch, thereby relieving pressure between the bottom row of cassettes and the forces being applied by the weight of the stacked rows of cassettes now being supported by the insertion and support platform  18  as shown in FIG.  5 A. The insertion and supporting platform  18  will continue pushing the bottom row of cassettes to the feed conveyor  20  across the magazine floor  22  while supporting the stacked rows of cassettes as shown in FIG.  6 . Once the bottom row of cassettes is in position on the feed conveyor  20 , the insertion and support member  18  will be withdrawn to its original starting position as shown in FIG.  3 . The magazine floor  22  will vertically return to its starting position, thereby providing a guide surface  24  for the row of cassettes as they travel along the feed conveyor  20 . A guide member  25  is positioned on the opposed side of the feed conveyor  20  to work with the guide surface  24  and properly align the cassettes as they proceed along the feed conveyor  20  to the assembly station  30 . 
     Sensing devices (not shown) such as light emitting diodes or polarized infrared scanners are positioned in the magazine  11  to signal when the last row of cassettes has exited the magazine, the signal being sent to the central processing unit  100  to notify the operator to refill the magazine  11 . Further sensors (not shown) are positioned about the feed conveyor  26  to monitor the flow of cassettes on the feed conveyor  20  and provide signals to the central processing unit when the feed conveyor  20  is clear for insertion of another row of cassettes and monitor the cassettes placed on the feed conveyor  20  to insure proper orientation and positioning of the cassettes as they approach the assembly station  30 . The conveyor guides  25  are preferably constructed of ultrahigh molecular weight polyethylene. The conveyor belts  26  of the feed conveyor  20 , as are all other conveyor belts of this invention, are constructed of true Teflon, the ends of which are laced together with a flush lacing designed to prevent tipping or otherwise disturbing the flow of cassettes to the assembly station  30 . The feed conveyor  20  is operated by motors  73 , preferably stepper motors, which index the feed conveyor belt  20  one cassette width at a time toward the assembly station  30 . 
     Referring to FIG. 8A, the assembly station  30  includes two conveyor sections which act in unison to assemble the cassettes and sheaths. A flight conveyor  27  is positioned proximate the end of the feed conveyor  20  to receive cassettes as they are indexed to the assembly station  30 . The flight conveyor  27  provides a vertical lift to each cassette and processes it into engagement with a prefolded, straightened and preglued sheath  40  positioned at the mouth of a compression conveyor  28 . The flight conveyor  27  includes a series of lift members  29  positioned on a belt or chain  31  which is preferably driven by a stepper motor  32 . The flight conveyor  27  also includes an aligning track  77  constructed of a Teflon material such as Delrinm which engages the ends of the cassettes and guides the cassettes in a desired orientation to the compression conveyor  28 . The stepper motor  32  receives signals from the central processing unit  100  which direct it to index the flight conveyor  27  one cassette at a time. Sensors  33 , such as infrared or light emitting diodes, monitor the positioning of the cassettes relative to the flight conveyor  27 . The sensor  33  provides a signal to the central processing unit which in turn provides input to a stop member  34  which, when activated, engages the cassette on the feed conveyor  20  to prevent the cassette from engaging the lift members  29  of the flight conveyor  27  until all systems of the machine are readied for operation and the cassettes are inspected for proper orientation by appropriate sensors. Preferably, the lift members  29  of the flight conveyor  27  are spring loaded, thereby providing engaging surfaces which create a cushioning effect when the cassettes are engaging each other in the aligning track  77  to prevent overloading the stepper motors driving the flight conveyor  27 . The central processing unit  100  receives signals from the various sensors and coordinates the operation of the stepper motors  73  which drive the feed conveyor  20 , the stepper motors  32  which drive the flight conveyor  27 , and the motors  26  which drive the sheath conveyor  36  and the motor (not shown) which drive the compression conveyor  28 . If the central processing unit  100  receives appropriate signals from the sensors that a cassette is in proper alignment with the flight conveyor  27 , the stop member  34  is signaled to release the cassette to be moved by the feed conveyor  20  into engagement with the lift members  29  of the flight conveyor  27 . The cassette is then transported by the flight conveyor  27  into the aligning track  77  toward the compression conveyor  28 . At the same time, a paper board sheath  40  is transported by the sheath conveyor  36  to a position immediately proximate the mouth of the compression conveyor  28 . The paper board sheath is engaged with the spine of the cassette at the entrance to the compression conveyor  28 . As the cassette and sheath  40  are carried into the compression conveyor  28 , the spine of the cassette and sheath are pressed against the immediately preceding cassette already in the compression conveyor, thereby compressing the paper board sheath  40  against the spine of the cassette. 
     The compression conveyor  28  is preferably constructed of opposed Teflon belts  37  carried by low crush rollers  38  and a plurality of flexible fins  39  positioned so as to provide continuous compressive forces against the sheath covered cassette as it travels through the compression conveyor  28  thereby causing the sheath to adhere to the cassette. 
     Referring now to FIGS. 7A and 7B, the sheath prefold and glue applicator apparatus  50  is shown. A stacking member  39  for retaining a stack of paper board sheaths which have the graphics for the particular video cassette preapplied includes a spring loaded elevator  41  which continuously raises as the sheaths  40  are removed from the stack. Vacuum pickups  42  remove the top sheath  40  from the stack of sheaths and place it into engagement with a positive drive roller  43  as shown in FIG. 7A. A sensor  44  determines the presence of sheaths in the stacking member  39  and if there are no sheaths remaining, the sensor  44  signals the central processing unit  100  to temporarily deactivate the machine until the stacking member  39  is replenished with sheaths. The sheath  40  is generally constructed of paperboard with appropriate graphics applied to one side. The sheath is precut and scored to provide the appropriate folding and openings necessary to properly encase the cassette. 
     After the sheath is driven through the positive drive roller  43  it engages a drive conveyor  45  which engages the spine of the sheath and drives the sheath through a folding station and an unfolding station. The drive conveyor  45  will support the sheath between a moving conveyor belt  74  and rollers  46 . As the sheath proceeds downstream from the positive drive roller  43  it first engages a prefold arm  47  which forces the sides of the sheath to fold along the scored lines which parallel the spine of the sheath. Upon exiting the prefold arm  47  and having a prefold placed along the scored line, the sheath engages a straightening arm  48  which unfolds and straightens the prefolded sheath. The straightened sheath is now limbered along its prefold scores which will enhance the ability of the sheath to fully encompass and adhere to the cassette in the compression conveyor  28 . After the sheath exits the straightening arm  48 , it is engaged by drive rollers  49  which propel the sheath past a glue application apparatus  51 . The glue application apparatus  51  includes a glue pot  52 , a feeding wheel  53  engaged with the glue pot  52  and a final glue application roller  54  which applies a measured amount of glue onto the non-graphic portion of the sheath on specified areas only. Preferably, the edges of the sheath are kept clean from glue so that, as the sheath is applied to the cassette in the compression conveyor  28 , excess glue will not be squeezed from the edges of the sheath onto the cassette or the drive mechanism of the machine. An opposed pair of driven Teflon belts  36  engage the sheath with glue applied, as it exits the glue application apparatus  51 , along the edges of the sheath to drive the sheath into its final position located at the entrance or mouth to the compression conveyor  28 . The parallel drive belts  36  which engage the edge of the sheath are positioned to apply a slight pressure to the sheath thereby causing the sheath to slightly fold or buckle along its scored lines, thereby enhancing adherence of the sheath to the cassette as the cassette engages the sheath by movement from the aligning track  77  to the compression conveyor  28 . 
     Appropriate sensors (not shown) are used to ensure that the glue pot maintains sufficient quantities of glue and to ensure proper positioning of the sheath with respect to the oncoming cassette at the mouth of the compression conveyor  28 . The sheath is also monitored as it passes through the prefold arm, straightening arm and drive rollers as well as the gluing station to ensure that the sheath maintains proper orientation and there are no defective sheaths entering the mouth of the compression conveyor  28 . If a defective sheath is located, the drive belts  36  are signaled by the central processing unit to reject the sheath from the assembly station  30 . 
     The operation of the assembly station can be followed by viewing FIGS. 7B and 8A. As the cassette is engaged by the flight conveyor  27  and lifted toward the aligning track  77  and compression conveyor  28 , the sheath  40  with preapplied glue is driven by the drive belts  36  into position at the mouth of the compression conveyor  28 . The cassette spine engages the spine of the sheath as the cassette is driven into the compression conveyor  28 . The top flap and bottom flap of the sheath are then pressed into engagement with the top surface and bottom surface of the cassette as the sheath and cassette are moved into the compression conveyor  28  between the low crush rollers  38  and Teflon belts  37 . Flexible fin members  39  are located along the travel path between the low crush rollers  38  and Teflon belts  37  continue the pressure on the Teflon belts  37  between the low crush rollers  38 . Flexible end fins  55 , shown in FIG. 7B, provide continuous pressure to the end flaps of the sheath, thereby pressing the end flaps of the sheath into engagement with the ends of the cassette. Thus, as the sheath encased cassette travels through the compression conveyor, the sheath is completely adhered to the cassette. The Teflon coated belts  37  are used throughout the compression conveyor  28  and other conveyor systems as they are impervious to the glue and any excess glue which may be squeezed from the cassettes and sheaths can be readily wiped off. 
     It is envisioned that automatic wipers for the Teflon belts  37  will be made as part of the overall apparatus of the invention. 
     As the sheath encased cassette exits the compression conveyor  28 , as shown in FIG. 8A, it enters a horizontally oriented compression chute  57  which maintains the cassette in an upright vertical position. A pushplate  78  driven by a pneumatically powered piston  79  engages each cassette as it exits the compression conveyor  28  and directs the cassette into the compression chute  57 . The compression chute  57  is designed to compress the top surfaces and bottom surfaces of adjacent cassettes together to facilitate the setting of the glue and final formation of the sheath application to the cassette. Further, rows of spaced resilient fins  58  are positioned to provide continuous pressure to the spine and ends of the cassette thereby applying continuous pressure to the spine and ends of the sheath, allowing the glue to set and permanently bond the sheath to the cassette. The resilient fins  58  may be constructed of any resilient and durable material. 
     Referring now to FIGS. 8B and 9, the sheath wrapped cassette exits the compression chute  57  and is flipped by a stop arm  59  to a horizontally oriented position and into engagement with a positioning conveyor  60 . It should be noted that the positioning conveyor  60  is constructed of polyurethane belts and is driven by motors  76  such as stepper motors which receive signals from the central processing unit to move the cassettes one cassette unit at a time. The positioning conveyor  60  feeds the final cassette products to the stacking station  61  which includes a bin  62  having side walls  63  and a vertically moveable floor  64 . Located at the top of the bin  62  in an area adjacent the positioning conveyor  60  is an aligning and orienting station  65 . The aligning and orienting station  65  includes support members  66  which receive the cassettes as they are being positioned at the top of the bin  62 . The aligning and orienting station  65  positions a preset number of cassettes for placement into the bin  62 . Appropriate sensors (not shown) provide signals to the central processing unit which indicate when the aligning and orienting station  65  has received its full compliment of cassettes. At that time a pneumatic piston  67  engaged with the support rails  66  of the aligning and orienting station  65  is signaled by the central processing unit to separate the support rails  66  apart, thereby releasing the row of cassettes to drop onto the floor  64  of the stacking bin  62  which is positioned immediately under the support rails  66 . A set of stops  68  located at the end of the positioning conveyor  60  are signalled by the central processing unit to close and prevent movement of cassettes from the positioning conveyor  60  onto the aligning and orienting station  65  when the aligning and orienting station  65  is full and the row of cassettes is being dropped to the floor  64  of the bin  62 . 
     The floor  64  of the bin  62  is supported by a pneumatic piston  69  and controlled by the central processing unit  100  to maintain a position immediately under support rails  66  of the aligning and orienting station  65 . After each row of cassettes is deposited onto the floor  64  of the bin  62 , a sensor (not shown) signals the central processing unit which in turn signals the lift piston  69  to lower the floor  64  of the bin  62  down one level of one cassette thickness, thereby allowing room for the next row of cassettes to be received from the aligning and orienting station  65 . Finally, the bin  62  includes a push wall  70  driven by a pneumatic piston  71  which is operated by signals from the central processing unit  100 . When sensors (not shown) positioned in the bin  62  indicate that the bin  62  is full of stacked rows of completed cassettes, the controller signals the piston  71  to drive the push wall  70  through the bin  62  thereby pushing a ready stack of cassettes onto the packaging table  72 . The floor  64  of the bin is then raised by its piston  69  back to its starting position. 
     While the current embodiment of the invention as described above dictates the use of specific types of drive mechanism, motors, rollers and sensors, it is fully envisioned that the substitution of equivalent structures for the pneumatic lifts, stepper motors, drive motors, compression rollers, conveyor belts, lift members, chain drives and gear and sprocket drives as well as any other structure in the invention, as shown in the figures, may be substituted without departing from the scope and overall vision of this invention.