Abstract:
A conveyor for a patty-forming apparatus is supported in cantilever fashion on support rods from the patty-forming apparatus. The conveyor includes an easily operated toggle mechanism to elevate the conveyor at a downstream end to facilitate sliding displacement of at least a portion of the conveyor on the support rods to gain access to portions of the apparatus. Particularly, the invention provides a lever action mechanism that tips the conveyor to raise a discharge end of conveyor. This mechanism facilitates sliding the conveyor out for access to knockout plungers of the apparatus. Elevation adjustment assemblies are arranged between the conveyor and the support rods. The set of the elevation assemblies is not affected by operation of the toggle mechanism.

Description:
[0001]     This application claims the benefit of U.S. Provisional Application 60/515,106 filed Oct. 28, 2003. 
     
    
     TECHNICAL FIELD OF THE INVENTION  
       [0002]     The invention relates to conveyors for food portion producing machines, particularly for reciprocating mold plate patty-forming machines.  
       BACKGROUND OF THE INVENTION  
       [0003]     A complete description of patty-forming machines can be found in U.S. Patent RE 30,096, U.S. patent application Ser. No. 60/503,354, filed Sep. 16, 2003, and U.S. patent application Ser. No. 10/942,627, filed on Sep. 16, 2004, all herein incorporated by reference. Patty-forming machines are also commercially available as FORMAX F-6, F-12, F-19, F-26, F-400 and MAXUM700 machines, from Formax, Inc., of Mokena, Ill., U.S.A.  
         [0004]     Beneath the discharge end of a patty-forming machine, and particularly beneath the knock out cups of a reciprocating mold plate patty-forming machine, a conveyor is arranged to receive the patties discharged from the mold plate. The conveyor is typically a stand-alone conveyor and supported from the floor on legs, and operates to discharge the patties to a downstream conveyor, freezer, packaging apparatus, or other downstream device.  
         [0005]     In such an arrangement, in order to maintain, retool, repair or clean the knock out end of the patty-forming apparatus, it is advantageous if the conveyor can be moved away from the knock out end. When the conveyor is reinstalled, typically both ends, and both sides, of the conveyor must be leveled and height-adjusted to maintain the correct relationship to adjacent upstream and downstream equipment.  
         [0006]     The present inventor has recognized that it would be advantageous to provide a conveyor that was easily moved to access adjacent equipment. The present inventor has recognized that would be advantageous to provide a conveyor that was easily movable to access adjacent equipment for maintenance and was easily placed back into correct operating position with regard to both the upstream and downstream equipment, without the need to readjust the elevation and leveling of the conveyor.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention provides an improved output conveyor for a food product-producing apparatus, such as a patty-forming apparatus. The conveyor is supported in cantilever fashion from the food product-producing apparatus. The conveyor includes an easily operated mechanism to elevate the conveyor at a downstream end to facilitate sliding removal of at least a portion of the conveyor to gain access to portions of the apparatus. Particularly, the invention provides a lever action mechanism that tips the conveyor to raise a discharge end of conveyor. This lever action mechanism facilitates sliding the conveyor outward for access to the output area of the apparatus.  
         [0008]     This mechanism also makes it easier to move downstream conveyors or systems without interference with the output conveyor.  
         [0009]     By using a fixed displacement toggling mechanism, once elevation and leveling of the conveyor is established, a re-establishing of heights need not be done after the output conveyor is moved from a maintenance position back into an operating position, i.e., the elevation and leveling of the conveyor does not have to be re-adjusted every time the output conveyor is moved away from the machine.  
         [0010]     When the food product-producing apparatus is a patty-forming apparatus, the conveyor can be slid away from a knockout area of the apparatus. As a further aspect of the invention, a knockout guard is pivotally mounted to the output conveyor to be moved with the output conveyor. The output conveyor can be slid away from the patty-forming apparatus, and folded away from the patty-forming apparatus, providing more access to the knockout plungers for tooling changes, repairs, adjustments, clean-up, and maintenance.  
         [0011]     As a further aspect of the invention, the output conveyor includes elevation adjustment assemblies to independently adjust the elevation of an input end of the conveyor and the elevation of an output end of the conveyor. Thus, the distance the patty drops onto the conveyor at the input end can be adjusted and the output end can be adjusted to match the downstream equipment.  
         [0012]     As a further aspect of the invention, the conveyor includes a drum motor drive that is easier to clean than external motors, reducers, chains or other power transmission devices.  
         [0013]     Numerous other advantages and features of the present invention will be become readily apparent from the following detailed description of the invention and the embodiments thereof, and from the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1  is a diagrammatic, elevational view of a patty-forming machine incorporating the conveyor of the present invention, with some panels and/or components removed for clarity;  
         [0015]      FIG. 2  is an enlarged, fragmentary view taken from  FIG. 1 ;  
         [0016]      FIG. 3  is an enlarged, fragmentary view taken from  FIG. 2 ;  
         [0017]      FIG. 4  is a diagrammatic elevational view of the patty-forming apparatus of  FIG. 1 , with the conveyor and in an extended, maintenance position, with some panels and/or components removed for clarity;  
         [0018]      FIG. 4A  is an enlarged, fragmentary view taken from  FIG. 4 , with the conveyor shown tilted down at its discharge end;  
         [0019]      FIG. 4B  is an enlarged fragmentary view taken from  FIG. 4 , with the conveyor shown tilted up at its discharge end;  
         [0020]      FIG. 4C  is an enlarged, fragmentary view taken from  FIG. 4A ;  
         [0021]      FIG. 5  is a sectional view taken generally along line  5 - 5  of  FIG. 4C , with some panels and/or components removed for clarity;  
         [0022]      FIG. 6  is a sectional view taken generally along line  6 - 6  of  FIG. 4C , with some panels and/or components removed for clarity;  
         [0023]      FIG. 7  is a is a sectional view taken generally along line  7 - 7  of  FIG. 4C , with some panels and/or components removed for clarity;  
         [0024]      FIG. 8  is a sectional view taken generally along line  8 - 8  of  FIG. 4C , with some panels and/or components removed for clarity;  
         [0025]      FIG. 9  is a sectional view taken generally along line  9 - 9  of  FIG. 4C , with some panels and/or components removed for clarity;  
         [0026]      FIG. 10  is a plan view of the conveyor taken generally along line  10 - 10  of  FIG. 2 , with some panels and/or components removed for clarity;  
         [0027]      FIG. 11  is a sectional view of the conveyor taken generally along line  11 - 11  of  FIG. 2 , with some panels and/or components removed for clarity; and  
         [0028]      FIG. 12  is a sectional view taken generally through line  12 - 12  of  FIG. 10 , with some panels and/or components removed for clarity. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0029]     While this invention is susceptible of embodiment in many different forms, there are shown in the drawings, and will be described herein in detail, specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated.  
         [0030]      FIG. 1  illustrates a patty-forming apparatus  20 . A complete description of patty-forming machines can be found in U.S. patent RE 30,096, U.S. patent application Ser. No. 60/503,354, filed Sep. 16, 2003, and U.S. patent application Ser. No. 10/942,627, filed on Sep. 16, 2004, all herein incorporated by reference. The apparatus  20  has a bin or hopper  24  for holding a supply of food material. Augers  26  deliver the food material into a food pump  28  which pumps food material through a manifold  30  and into cavities of a reciprocating mold plate  32 . A powered bucket lift  34  lifts buckets  35  containing food material and discharges the content of the buckets into the hopper  24 .  
         [0031]     The patties are discharged from the cavities of the mold plate  32  by vertically reciprocating knock out plungers or cups  38  (see  FIG. 2 ), located behind a guard  42 . The patties are deposited onto an output conveyor  46  to be transported to the discharge or output end  47  thereof, to be delivered to another conveyor  48 , or to another piece of equipment.  
         [0032]     Also shown in  FIG. 1  is the conveyor  46  having a lowered discharge end  47 A that is angled to match an input end of the conveyor  48  being at a lower position  48 A. An elevated position  47 E of the conveyor end  47  is also shown. The elevated position is used to slide the conveyor  46  away from the patty-forming apparatus and partly over the conveyor  48 , or other equipment, to gain access to the knock out cups  38  and the corresponding area of the apparatus  20  for maintenance, cleaning, repair or retooling.  
         [0033]      FIGS. 2 through 12  illustrate the conveyor  46  in more detail. Portions of the conveyor  46 , such as frame sidewalls are shown transparent or removed for clarity. The conveyor  46  is operable over an angular range “b” at its discharge end  47  from the position shown as  47  to the position shown as  47 A. The conveyor  46  includes a rear toggle or lever arrangement  49 , described below, which allows the conveyor end  47  to shift from any fixed position throughout the angle “b” to an elevated position  47 E that is the distance “a” higher than the particular operating position. According to the preferred embodiment the distance “a” is about 2 inches, preferably 1.8 inches.  
         [0034]     As illustrated in  FIGS. 2 and 4 C, the conveyor  46  comprises a continuous wire belt  52  such as one provided by The Wire Belt Company of America. The belt  52  is circulated around a rear roller  56 , a bottom first roller  60 , a drum motor  62 , a bottom second roller  63 , a front roller  64  and an intermediate roller  68 . The intermediate roller  68  is carried by a front frame  72 . The frame  72  is selectively angled to lower the front roller  64 , such that a front portion  75  of the belt  52 , between the intermediate roller  68  and the front roller  64 , can be set at the desired angle.  
         [0035]     The drum motor  62  can be a DURA-DRIVE Drum Motor available from Sparks Belting Company, of Grand Rapids, Mich., U.S.A.  
         [0036]     The rear roller  56 , the bottom roller  60 , the drum motor  62 , and the bottom second roller  63  are carried by sidewalls  80   a ,  80   b  of an inside conveyor frame  80 . The bottom roller  60 , the drum motor  62 , and the bottom second roller  63  are mounted directly onto the sidewalls  80   a ,  80   b.    
         [0037]     Referring to  FIGS. 4C and 10 , the front frame  72  is fastened to the sidewalls  80   a ,  80   b  of the inside frame  80  by a pivot strut  82  and an angle-set strut  86 . The struts  82 ,  86  have opposite end tapped holes that receive fasteners  82   a ,  86   a . The struts  82 ,  86  are received through apertures through the front frame  72 . The struts  82 ,  86  are tubes or rods and have a lesser outside diameters than the apertures through the front frame  72 . The struts abut an inside face of the inside frame  80  on each sidewall  80   a ,  80   b , in registry with an aperture and a curved slot  88  on each sidewall  80   a ,  80   b . The strut  82  has a greater outside diameter than the aperture through the inside frame sidewalls  80   a ,  80   b  and the strut  86  has an outside diameter greater than a width of the curved slot  88  through the inside frame sidewalls  80   a ,  80   b . The pivot fasteners  82   a  capture both sidewalls  80   a ,  80   b  of the inside frame  80  between the head of the respective pivot fastener  82   a  and the strut  82 . The angle-set fasteners  86   a  capture the sidewalls  80   a ,  80   b  of the inside frame  80  between the head of the respective angle-set fastener  86   a  and the strut  86 , at a selected position in the curved slot  88 . Thus the fasteners  82   a ,  86   a  can be loosened and the angle of the front frame  72  can be set with respect to the inside frame  80 .  
         [0038]     Referring to  FIGS. 2 and 10 , the conveyor  46  is supported by parallel, longitudinally extended horizontal support rods  104   a ,  104   b . The rods  104   a ,  104   b  are fixed into base blocks  106   a ,  106   b  on the machine frame and secured thereto by fasteners  108   a ,  108   b . The base blocks  106   a ,  106   b  support the rods  104   a ,  104   b  in cantilever fashion.  
         [0039]     The conveyer  46  has an outer frame  120  having sidewalls  120   a ,  120   b  having inwardly directed rear flanges  122   a ,  122   b  as shown in  FIG. 5 , inwardly directed front flanges  124   a ,  124   b  as shown in  FIG. 12 , and inwardly directed bottom flanges  126   a ,  126   b , as shown in  FIGS. 5-9 .  
         [0040]     Referring to  FIGS. 4A and 10 , the rear flanges  122   a ,  122   b  carry rear slide bearings  130   a ,  130   b  and the front flanges  124   a ,  124   b  carry front slide bearings  132   a ,  132   b . The slide bearings  130   a ,  132   a  journal sliding movement of the conveyor on the rod  104   a  and the slide bearings  130   b ,  132   b  journal sliding movement of the conveyor on the rod  104   b.    
         [0041]     Referring to  FIGS. 2, 6  and  9 , the inside frame  80  is supported on the outside frame  120  via rear elevation adjustment assemblies  140   a ,  140   b  and front elevation adjustment assemblies  142   a ,  142   b , described below.  
         [0042]     Referring to  FIGS. 2 and 10 , a front toggle or lever assembly  170  is used to slide the conveyor  46  on the rods  104   a ,  104   b.    
         [0043]     Referring to FIGS.  4 C,  10 - 12 , a drip pan  174  is fixed to the outer frame sidewalls  120   a ,  120   b . A respective pivot connection  178   a ,  178   b  is mounted on the pan  174  or otherwise connected to the sidewalls  120   a ,  120   b , via fasteners  180 . The pivot connections journal opposite ends of a hinge rod  182 . The guard  42  is hingedly attached to the hinge rod  182  via hinge journals  186   a ,  186   b  that are attached to the guard  42  by fasteners  190 . The guard  42  can pivot freely on the hinge rod  182 .  
         [0044]     The front toggle or lever assembly  170  includes rod fixtures  194   a ,  194   b  fixed onto ends of the rods  104   a ,  104   b . Each fixture  194   a ,  194   b  includes a laterally oriented pivot connection  196  created and retained by a fastener  196   a . Each first link  202  extends from the pivot connection  196  to a handle assembly  206 . Each handle assembly includes a handle  208 , a pivot connection  210 , a rest  212 , and an extension  213 . The pivot connection connects the handle  210 , the rest  212  and the extension  213  to the first link  202  and to a second link  216 . A fastener  220  creates and retains the pivot connection  210 .  
         [0045]     Each second link  216  is pivotally connected to the respective pivot connection  178   a ,  178   b  by a retainer  226  and a fastener  230 . The fastener  230  is engaged into an end of the hinge rod  182  and, together with the retainer  226  retains second link  216  at the respective pivot connection  178   a ,  178   b.    
         [0046]     By grasping both handles  208  on opposite sides of the conveyor  46  and exerting a force forwardly, the conveyor can be extended to its maintenance position as shown in  FIGS. 4-4C . The links  202 ,  206  fold into a “7” shape as shown, as the outside frame  120 , and thus the inside frame  80  also, slides on the rods  104   a ,  104   b  forwardly until contact is made between the bearings  132   a ,  132   b  and the rod fixtures  194   a ,  194   b  on the rods  104   a ,  104   b.    
         [0047]     When the conveyor  46  is slid rearward to an operating position, and the guard is swung down to its operating position as shown in  FIG. 2 , the toggle assembly  170  assumes the locked position shown in  FIG. 2  with the links  202 ,  216  assuming an over center locked orientation. The extensions  213  contact the rods  104   a ,  104   b  which act as stops for the toggle assembly, as shown in  FIGS. 2 and 10 .  
         [0048]     In the position shown in  FIG. 4C , the guard  42  can be opened and supported as shown with the shoulders  42   d  resting on the rests  212 .  
         [0049]     Referring to  FIGS. 2, 4C ,  10  and  12 , the guard  42  includes a top wall  42   a , a flange  42   b  extending above the top wall  42   a , upper sidewalls  42   c , side shoulders  42   d , an inclined front wall  42   e , a straight front wall  42   h , and lower sidewalls  42   f . The guard is configured in mirror image fashion about a longitudinal centerline. The flange  42   b  includes a target  42   g  for being sensed by a sensor  230  to determine in machine control whether or not the guard  42  is in position.  
         [0050]     The top wall  42   a  includes a rectangular cutout  42   k  ( FIG. 10 ) corresponding generally to the knockout area. The upper sidewalls  42   c  include oblong openings  42   j  ( FIG. 2 ). All other portions  42   d ,  42   e ,  42   h , and  42   f  of the guard  42  are substantially solid.  
         [0051]     Each elevation adjustment assembly  140   a ,  142   a ,  140   b ,  142   b  is configured essentially the same. As an example, the assembly  140   a  will be explained. Referring to  FIG. 6 , the elevation adjustment assembly  140   a  includes a threaded rod  260 , having threads in a first region  260   a  and a second region  260   b . A locking knob  262  is threaded onto the region  260   b . A yoke  266 , which can be in block or cylinder form, has a threaded bore  268  threaded onto the region  260   a . The yoke has a cross bore  270  for receiving a rod  274 . The rod  274  is supported at its opposite end by the elevation adjustment assembly  140   b . The rod  274  supports a rear portion of the inside frame  80 . An adjustment knob  282  is rotationally fixed to an end of the threaded rod  260  to turn the threaded rod by hand.  
         [0052]     The threaded rod  260  includes a shoulder portion  260   c  adjacent to the flange  126   a  of the outside frame  120 . When elevation adjustments are completed, the locking knob  262  can be elevated on the threaded region  260   b  by turning the knob  262  while holding the adjustment knob  282  to prevent the rod  260  from turning. The locking knob  262  is elevated until the flange  126   a  is tightly clamped between the shoulder portion  260   c  of the threaded rod  260  and the locking knob  262 . The threaded rod rotary position is thus locked and prevented from changing during operation.  
         [0053]     As shown in  FIG. 9 , the elevation adjustment assemblies  142   a ,  142   b  support a rod  294  that supports a front portion of the sidewalls  80   a ,  80   b  of the inside frame.  
         [0054]     Referring to  FIG. 4C , the height adjustment assemblies  140   a ,  140   b ,  142   a ,  142   b  can be independently adjusted to level the conveyor  46 . A series of markings or gradations  295  is provided at each height adjustment assembly. The gradations can be marked off at ¼ inch increments. A corresponding mark on the yoke  266 , visible through an opening in the respective sidewall  120   a ,  120   b  can be used to set the elevation.  
         [0055]     The rear toggle assembly  49  acts to lower the rear end of the inside frame  80  with respect to the outside frame  120 , and effectively raise the discharge end  47 , by pivoting the inside frame  80  about the rod  294 . In this way, the front frame  72  is pivoted upward and can slide over an adjacent piece of equipment, such as the conveyor  48  shown in  FIG. 1 , for maintenance, cleaning, repair or retooling, particularly of the knock out area of the apparatus  20 .  
         [0056]     The rear toggle assembly  49  is shown in detail in  FIGS. 3 and 6 . The rear toggle assembly  49  is configured in mirror image fashion across a longitudinal vertical center plane of the conveyor. The assembly includes levers  320   a ,  320   b  on opposite sides of the conveyor  46 . Each lever is rigidly connected to an end of the rod  274  by use of a square peg or by a key arrangement, or other arrangement such that turning the lever turns the rod  274 . A first link  322  is also fixedly connected to the rod by a keying arrangement or other arrangement, such that turning the rod  274  swings the first link  322  about the centerline of the rod  274 . The first link  322  is pivotally connected to a second link  326  at a first end thereof, the second link being pivotally connected to a support rod  336  at a second end thereof. The support rod  336  supports the inside frame  80 .  
         [0057]     As shown in  FIG. 3 , when the lever  320   a  is turned up, the first and second links are substantially vertical, and slightly over center to be locked in place. The support rod  336  is at a relatively high elevation. When the lever is turned down to the position indicated as  320   aa , the links  322  and  326  are to an extent folded together to the positions indicated as  322   aa ,  326   aa , and the elevation of the support rod  336  is lowered to the position indicated as  336   aa . When the support rod  336  is lowered, the discharge end  47  of the conveyor is raised as the conveyor pivots. This would be a position wherein the conveyor can be slid out longitudinally, using the front toggle assembly  170  so that access is available to the knock out cup area.  
         [0058]     Stops are provided to limit the counterclockwise rotary movement of the levers  320   a ,  320   b  to the vertical position shown in  FIG. 3  and to limit the clockwise rotation of the levers  320   a ,  320   b  to the phantom position of the levers  320   a ,  320   b  shown in  FIG. 3  as  320   aa . Particularly, tubular end portions  390   a ,  390   b  of a strut  390 , each located outside a sidewall  80   a ,  80   b , form one stop. Short rods  389   a ,  389   b  arranged on respective sidewalls  80   a ,  80   b  form the other stop.  
         [0059]      FIG. 3  illustrates components of the conveyor in an operating (elevated) and maintenance (lowered) position. The stop  390   a  is shown in its elevated position, and in its lowered position indicated as  390   aa . The rear roller  56  is shown in its elevated position, and in its lowered position indicated as  56   aa . The stop  389   a  is shown in its elevated operating position, and in its lowered maintenance position, indicated as  389   aa  where it engages the link  326  shown in its folded position as  326   aa.    
         [0060]     The figures also illustrate miscellaneous structural struts that rigidify the inside frame between the opposite sidewalls  80   a ,  80   b . Each strut includes a solid rod, spacer or tube between the sidewalls and end fasteners engageable into ends of the tube to connect the tube at opposite ends to the sidewalls  80   a ,  80   b . The struts are marked  390 ,  391 ,  392 ,  393 ,  408  and  468  shown in  FIGS. 4C, 5 ,  6  and  8 . When a solid rod strut is used, the ends of the strut are beveled to form a reduced diameter end portion adjacent a shoulder. The shoulder is pressed against the inside surface of the respective sidewall and the reduced diameter end portion fits closely into a hole through the sidewall. A fastener then clamps the sidewall between a washer on an outside and a shoulder on the inside of the sidewall. The fastener is threaded into a tapped hole on an end of the rod. In the case of the strut  390  the tubular end portions are fit between the washer and the outside of the respective sidewall  80   a ,  80   b.    
         [0061]     The figures also illustrate miscellaneous structural struts that rigidify the outside frame  120  between the opposite sidewalls  120   a ,  120   b . Each strut includes a solid rod, spacer or tube between the sidewalls and end fasteners engageable into ends of the tube to connect the tube at opposite ends to the sidewalls  120   a ,  120   b . When a solid rod strut is used, the ends of the strut are beveled to form a reduced diameter end portion adjacent a shoulder. The shoulder is pressed against the inside surface of the respective sidewall and the reduced diameter end portion fits closely into a hole through the sidewall. A fastener then clamps the sidewall between a washer on an outside and a shoulder on the inside of the sidewall. The fastener is threaded into a tapped hole on an end of the rod. The struts are marked  404 ,  406  shown in  FIGS. 4C, 6 , and  7 .  
         [0062]     The struts  408  and  391  support a drip shield  430  that directs drippings into a recovery trough  434  ( FIG. 2 ).  
         [0063]     The figures also illustrate a structural strut  440  that rigidifies the front frame  72  between the opposite sidewalls  72   a ,  72   b . The strut includes a spacer or tube between the sidewalls and end fasteners engageable into ends of the tube to connect the tube at opposite ends to the sidewalls  72   a ,  72   b . The strut  440  is shown in  FIGS. 4A, 11  and  12 .  
         [0064]     As illustrated in  FIGS. 10 and 11 , the rear roller  56  is journaled by longitudinal conveyor support members  462 ,  464  that are supported by support rod  336  and by strut  468 . The rod  336  and strut  468  penetrate through the members  462 ,  464 . The members  462 ,  464  are fixed to the strut  468  by fasteners. The rod  336  and strut  468  also penetrate through a plurality of conveyor supports  480  in like fashion. Longer conveyor supports  486  extend from the strut  468  to the angle set strut  86  and are fixed at both ends by fasteners. Further conveyor supports  494  are captured by being penetrated at one end by the pivot strut  82  and are fastened at an opposite end by fasteners to the strut  440 .  
         [0065]     The conveyor belt  52  moves over and is supported by the members and supports  462 ,  464 ,  480 ,  486 ,  494 .  
         [0066]     Because the rear roller  56  is not journalled directly to the sidewalls  80   a ,  80   b , but journalled through intervening supports  462 ,  464 , the angle to horizontal of the short supports  480  and the members  462 ,  464  can be set independently of the longer supports  486  by varying the relative angle of the members and supports  462 ,  464 ,  480  with respect to the supports  486  at the strut  468 . Thus, the members  462 ,  464  and supports,  480 , in the location where the patties land from the mold plate, can be kept level, notwithstanding the angle of the remaining portion of the conveyor top surface.  
         [0067]     Also, as the angle of the front frame  72  is set with respect to the inside frame  80 , the supports  494  are set at an angle to the longer supports  486  such that the top conveying surface can be set in three distinct planes: an input area, an intermediate area, and an output area.  
         [0068]     From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred.