Abstract:
The present invention is directed to a vertical displacement conveyor system for collecting and transporting objects, such as food trays, from a drop-off area to a receiving area. The conveyor system follows a vertical planar path, thereby allowing the drop-off area and the receiving area to be set at different elevations or at the same elevation and providing a smaller space footprint. The present invention is also directed to a vertical conveyor system for transporting and displaying object, such as bottles. A basket holding bottles is coupled to the conveyor system and then is transported in planar path for display.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims priority to U.S. provisional application Ser. No. 60/582,249 entitled “Apparatus for Automatically Collecting and Transporting Objects,” filed Jun. 22, 2004, the contents of which are incorporated herein by reference in its entirety for all purposes. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of Invention  
         [0003]     The present invention is directed to an apparatus for automatically collecting and transporting objects such as food-carrying trays or cafeteria trays, wherein the trays can be efficiently and quickly collected at a designated drop-off area and transported to a designated receiving location via a transportation route that is at least in part vertically above or below the drop-off area.  
         [0004]     2. Description of Related Art  
         [0005]     In a self-service cafeteria or a restaurant setting in which food items and food wares are served on a tray, such as a standard 14 inches by 18 inches cafeteria tray, and in which the patrons are asked to return the trays to a designated drop-off location, it is well known in the art that conveyor systems may be employed to automatically pick up and transport the returned trays from the drop-off location to a receiving location, where employees of the cafeteria or the restaurant can pick up the dropped off trays and remove the soiled ware from the trays. In order to effect such an automatic system, a conveyor system using a rotating conveyor belt is typically used to transport the trays laterally from one location to the other.  
         [0006]      FIG. 1A  of the present application illustrates a top view of a lateral movement conveyor system. Specifically,  FIG. 1A  shows a lateral movement conveyor system  1  in which tray carriers  2  move laterally along a motorized conveyor system in a circular direction (as indicated by the arrows), rotating around a common wall  3  that separates the cafeteria or restaurant area  4  from the dish room  5 , where the trays are off loaded and cleaned. As shown in  FIG. 1A , patrons carrying food trays can drop off the trays at a drop-off window  6 . The moving tray carrier then carries the dropped off food tray from the drop-off window  6  around the common wall  3  to the other side for off loading. As discussed above, a typical food tray measures 14 inches by 18 inches. The tray carriers  2  shown in  FIG. 1A  are preferably sufficiently deep and wide so as to be able to receive trays that are loaded in either orientation (i.e., either side ways or long ways).  
         [0007]     In accordance with a more conventional type of conveyor system, the tray carriers are not employed; instead, a simple conveyor belt is used to transport the trays from the drop-off location to the receiving area. In the more conventional system where simply the conveyor belt is used, the belts or at least the transport canal on which the belt travels must be sufficiently wide to accommodate side loading of the trays. Hence, a system as shown in  FIG. 1A  must be designed to be at least 18 inches wide on each side of the common wall, wherein the wall itself needs to be at least a foot wide to allow sufficient room for maneuvering the trays from one side of the wall to the other and to provide sufficient separation. Accordingly, a typical system as shown in  FIG. 1A  needs to be almost five feet wide to accommodate proper tray transportation.  
         [0008]      FIG. 1B  shows a side view of the system shown in  FIG. 1A . As shown in  FIG. 1B , the tray carriers  2  may be a multi-stacked receptacle for carrying multiple trays one on top of another. By employing a multi-stacked tray carrier system, the system of  FIG. 1B  can transport more trays at the same time, thereby potentially reducing the length of the conveyor system while maintaining or even increasing the load capacity of the system.  
         [0009]     The system shown in  FIGS. 1A and 1B  is a lateral movement system in which the trays are moved laterally from one location to another location. The system of  FIGS. 1A and 1B  has a disadvantage in that the dishwashing room, or otherwise known as the “wet area,” must be located on the same floor as the dining area, since the trays or carriers can only be moved laterally. As a result, the dining area of the cafeteria or the restaurant must be reduced to accommodate the wet area, lowering the maximum capacity of the cafeteria or the restaurant.  
       SUMMARY OF THE PRESENT INVENTION  
       [0010]     The present invention is directed to a vertical displacement conveyor system for collecting and transporting the food trays from a drop-off area or location to a receiving area using vertical displacement of the food trays along the way.  
         [0011]     The present invention offers the advantage of the ability to locate the wet area on a different vertical elevation or even a different floor than the dining area to thereby maximize the dining area or wet area of a cafeteria or a restaurant. Another aspect of the preferred embodiment of the present invention maintains or even increases the capacity of the conveyor system while at the same time minimizing the floor space requirements, or indeed even reduce the floor space requirement, for installing the system.  
         [0012]     In accordance with an alternative embodiment of the present invention, the wet area are located on the same level as the dining area, but through the use of vertical displacement of the tray carriers in an “over and under” configuration, the total size of the tray transportation system maybe reduced.  
         [0013]     In accordance with yet another embodiment of the present invention, objects such as bottles may be transported in a vertical manner for display purposes using carriers of different construction. The different embodiments of the present invention are discussed in detail below.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1A  illustrates a top view of a lateral displacement conveyor system for transporting objects.  
         [0015]      FIG. 1B  illustrates a side view of the lateral displacement conveyor system of  FIG. 1A .  
         [0016]      FIG. 2A  illustrates a front view of a vertical displacement conveyor system in accordance with a preferred embodiment of the present invention.  
         [0017]      FIG. 2B  illustrates a side view of the preferred embodiment of  FIG. 2A .  
         [0018]      FIG. 2C  illustrates a top view of the preferred embodiment of  FIG. 2A .  
         [0019]     FIGS.  2 D( 1 ),  2 D( 2 ) and  2 D( 3 ) illustrate a multi-floor floor plan incorporating the vertical displacement conveyor system in accordance with the preferred embodiment of the present invention.  
         [0020]      FIG. 2E  illustrates a front-view of one embodiment of an “over and under” configuration.  
         [0021]      FIG. 2F  illustrates a side view of the embodiment of  FIG. 2E .  
         [0022]      FIG. 2G  illustrates different drive options.  
         [0023]     FIGS.  3 A( 1 ),  3 A( 2 ),  3 A( 3 ),  3 A( 4 ),  3 A( 5 ),  3 A( 6 ),  3 A( 7 ),  3 A( 8 ),  3 A( 9 ),  3 A( 10 ),  3 A( 11 ),  3 A( 12 ),  3 A( 13 ),  3 A( 14 ) and  3 A( 15 ) illustrate various views of a vertical displacement conveyor system in accordance with an alternative embodiment of the present invention.  
         [0024]      FIG. 3B  illustrates a front view of the vertical displacement conveyor system in accordance with the alternative embodiment.  
         [0025]      FIG. 3C  illustrates a rear view of the vertical displacement conveyor system in accordance with the alternative embodiment.  
         [0026]      FIG. 3D  illustrates a side view of the vertical displacement conveyor system in accordance with the alternative embodiment.  
         [0027]      FIG. 3E  illustrates a carrier employed in the vertical displacement conveyor system of the alternative embodiment.  
         [0028]      FIG. 3F  illustrates the internal construction of the vertical displacement conveyor system of the alternative embodiment.  
         [0029]      FIG. 3G  illustrates a front view of the frame construction of the vertical displacement conveyor system of  FIG. 3F .  
         [0030]      FIG. 3H  illustrates a top view of the frame construction of the vertical displacement conveyor system of  FIG. 3F .  
         [0031]      FIG. 3I  illustrates a side view of the frame construction of the vertical displacement conveyor system of  FIG. 3F .  
         [0032]      FIG. 3J  illustrates a cross-sectional view of the frame of the vertical displacement conveyor system of  FIG. 3G  along the A-A line.  
         [0033]      FIG. 3K  illustrates a cross-sectional view of the frame of the vertical displacement conveyor system of  FIG. 3G  along the B-B line.  
         [0034]      FIG. 3L  illustrates a cross-sectional view of the frame of the vertical displacement conveyor system of  FIG. 3G  along the C-C line.  
         [0035]      FIG. 3M  illustrates a cross-sectional view of the frame of the vertical displacement conveyor system of  FIG. 3H  along the D-D line. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0036]     Detailed descriptions of the preferred embodiments will now be provided with references to  FIGS. 2A-3M .  
         [0037]      FIG. 2A  illustrates a front view of a vertical displacement conveyor system  100  in accordance with a preferred embodiment of the present invention. As shown in  FIG. 2A , carriers  110  are preferably attached to a transporting mechanism  120  of the conveyor system that transports the carriers  110  both laterally and vertically, in either a clockwise or counterclockwise direction. The transporting mechanism  120  comprises a group of gears or sprockets  125  that are placed throughout the system.  FIG. 2A  illustrates four gears placed at the four corners of the system. The gears are linked through a chain which is guided through a series or rails or guides  121 ,  122 ,  123  and  124 . The carriers  110  are coupled to the chain, such as with a bolt or pin  114  as illustrated in  FIG. 2B . When the gears are driven by a motor (not illustrated in  FIG. 2A ), the chain is correspondingly driven along the path defined by the gears and guides, thereby driving the carriers  110  along the path.  
         [0038]     In a self-service cafeteria environment, a patron of the cafeteria can drop off trays into one of the carriers  110  that pass by the drop-off window  130 , after which the carriers are moved along the conveyor system  100  to a receiving area for off loading before returning to the drop-off window.  FIG. 2B  shows a side view of the preferred embodiment. As seen in  FIG. 2B , the carriers  110  are preferably made of multiple receptacles such as  111  and  112  stacked vertically for carrying multiple trays. By using multiple receptacles, each carrier can carry multiple number of trays and therefore increase the carrying capacity of the conveyor system.  
         [0039]      FIG. 2C  shows a top view of the vertical displacement conveyor system in accordance with the preferred embodiment. As can be seen from the top view, a receiving window  140  is preferably located on a side of the conveyor system opposite that of the drop-off window  130 . However, the location of the receiving window  140  can also be located on the same side as the drop-off window  130 , or even on the side walls  150  and  160  of the conveyor system  100 . Moreover, the location of the receiving window  140  and the drop-off window  130  can be located on either the same vertical elevation or different vertical elevation, even different floors of a building. It should be understood that the location of both the drop-off window  130  and the receiving window  140  can be however located to best suit the needed application or space restriction.  
         [0040]     FIGS.  2 D( 1 ),  2 D( 2 ) and  2 D( 3 ) show an implementation of the preferred embodiment of the present invention. As shown in  FIG. 2D ( 1 ), the vertical displacement conveyor system  200  is installed such that the drop-off area  210  and the receiving/wet area  220  are located on different floors  230  and  240  respectively. Specifically, the drop-off area  210  of the system  200  shown in  FIG. 2D ( 1 ) is located on a floor  230  above the receiving/wet area  220  of the system. A patron may place a tray into one of the carriers  212  passing through the drop-off window  211  which is elevated by a stub wall or panel enclosure  213 , after which the carrier  212  travels along the conveyor transportation mechanism  250  in a clockwise direction towards the receiving area  220  located on a floor  240  below. The trays may be off loaded from the carriers  212  to dish table  221  at the receiving area  220  downstairs from the drop-off area  210 , after which the carriers  212  travel back up towards the drop-off area  210 . The conveyor transportation mechanism  250  may be operated so that the carriers  212  travel continuously, or intermittently with occasional pauses.  FIG. 2D ( 2 ) shows a top view of receiving area  220  of the conveyor system  200 .  FIG. 2D ( 3 ) shows a top view of the drop off area  210  of the conveyor system  200 .  
         [0041]     As discussed above, a typical cafeteria food tray measures about 18 inches by 14 inches. In a conventional lateral displacement conveyor system such as the one shown in  FIG. 1A , where the trays are loaded side ways into the system, the apparatus must have a minimum width of around 60 inches to accommodate the trays on both sides and the common wall in between. The preferred embodiment of the present invention, on the other hand, allows the trays to be returned above or below (as shown in  FIG. 2B ), and hence only requires a maximum width of around 34 inches. Of course, these measurements are only cited for illustration purposes, and should not be interpreted as limitations.  
         [0042]      FIGS. 2E and 2F  illustrate one embodiment of an over-under configuration. Such a configuration can be used when a rectangular path is not available due to space constraints or other constraints. The vertical conveyor system  260  of  FIGS. 2E and 2F  transports carriers, such as carrier  267 . The carrier  267  can be a multi-tray carrier as illustrated in  FIG. 2F . Carrier  267  has a counterweight  270  to ensure stability as it is driven along the vertical conveyor system. A guide mechanism illustrated at  280  at the bottom portion of the carrier further ensures stability as well as guide the carrier along its path.  
         [0043]     The vertical conveyor system  260  transports the carriers between a lower level and an upper level. The lower level is defined by floor  261  and ceiling  262 . The upper level is defined by floor  263  and ceiling  264 . The distance Y 7  between the floor  263  of the upper level and the ceiling  262  of the lower level can be 4 feet.  
         [0044]     Customers or patrons can place trays or other objects in a carrier  267  at window  265 . The window  265  can be placed at a height Y 2  of 3 feet above floor  263 . The height Y 5  of the window, itself, can be 2 feet, 3 inches as illustrated in  FIG. 2F  while the height Y 1  to the ceiling  264  can be six feet.  
         [0045]     The conveyor system then transports the carrier  267  horizontally along the window  265  in the direction of the arrow of  FIG. 2E . As it nears the right side of the system, the carrier  267  is transported vertically up and then horizontally along an upper path as indicated by the arrow in  FIG. 2E . The horizontal and vertical movements are achieved through a series of gears or sprockets  268  placed throughout the conveyor system. Each carrier is coupled to a chain guided by a rail or guide and driven by the gears. The gears in turn are driven by a motor  271 . The motor  271  can drive one or more gears through a chain as illustrated in  FIG. 2E .  FIG. 2G  also illustrates a side view of motor  290  driving a gear  268  through a chain  291 .  FIG. 2G  also illustrates another embodiment in which the gear  268  is directly driven by a motor  292  without a chain.  
         [0046]     As the carrier  267  nears the left side of the upper level, it transported vertically down toward the lower level along a vertical path as indicated by the arrow. As the carrier heads down vertically, other carriers are heading up vertically along an adjacent path. The width X 2  of the two paths can be five feet, six inches. The carrier  267  then emerges at the lower level through receiving area having a receiving window  266 . The receiving window  266  can be placed at a height Y 4  of 3 feet above floor  261 . The height Y 3  to the ceiling  262  can be six feet. Adjacent to the receiving area is a dish table  269  as illustrated in  FIG. 2F , having a height Y 6  of 2 feet, 10 inches.  
         [0047]     As the carrier  267  travels along the receiving area, an individual can unload the trays or other objects from carrier  257 . The carrier  267  continues horizontal until it reaches the right side of the system, upon which is travels vertically as indicated by the arrow. The carrier  267  then travels along a horizontal and vertical path as it returns to window  265  to be loaded with trays or other objects.  
         [0048]     It should be understood to one skilled in the art that different types of motors and drive mechanism can be used to effect the transport mechanism mentioned above.  
         [0049]      FIG. 3A  illustrates various views of a vertical displacement conveyor system in accordance with an alternative embodiment of the present invention.  
         [0050]     As shown in  FIG. 3B , the vertical displacement conveyor system  300  can also be used to transport other types of objects such as bottles or liquid containers  310 . The containers  310  are stored in carriers  330  and transported along a rectangular path. The path is defined by four internal rails  321 ,  322 ,  323  and  324  with gears or sprockets at each corner. Only gear  403  is illustrated in  FIG. 3B  while  FIG. 3F  illustrates all four gears. A motor (such as motor  441  illustrated in FIGS.  3 A( 3 ) and  3 A( 4 ) drives the carriers  330  along the internal rails and gears through a chain (also not illustrated). The operation of the system is controlled by control panel  340 . The control panel can be mounted in a mounting bracket such as bracket  441  in FIGS.  3 A( 1 ) and  3 A( 2 ).  
         [0051]     To guide the carriers  330  during transportation, six guide rails  320  are positioned to be adjacent to the sides or bottom of the carriers  330 . As discussed below with respect to  FIGS. 3D and 3E , each of the carriers  330  has corresponding guide elements that follow the guide rails  320 .  
         [0052]     The height H and width W of the system  300  can be 9 feet, 4 inches and 4 feet, 7 inches respectively. The depth D of the system  300  can be 1 foot as illustrated in  FIG. 3D . An advantage offered by this alternative embodiment is the ability to store multiple bottles of liquid while minimizing the horizontal space required for storing the bottles. At the same time, this alternative embodiment provides the advantage of displaying the bottles in an aesthetically unique manner. Such conveyor systems may be used at places such as nightclubs or bars that may benefit from aesthetic display of alcoholic beverage containers.  FIGS. 3C and 3D  illustrate a rear view and side view of the alternative embodiment, respectively. As illustrated in both figures, the rear of the conveyor system  300  can be enclosed by sliding doors  350 . The sliding doors provide access to the internal mechanisms and structure of the system. For example, as illustrated in  FIG. 3A ( 2 ), a user can access the motor  441  or the control panel  340  supported by mounting bracket  440 . Access is also available to brackets  500  that hold the gears or sprockets of the system as discussed below.  
         [0053]      FIG. 3E  shows an isometric view of carrier  330  of the conveyor system  300  in accordance with the alternative embodiment. The carrier  330  comprises a basket  331 . The basket is designed to securely hold at least one container, such as a bottle. The basket  331  is connected to a metal handle  332 . The metal handle  332  is shaped to allow the placement of containers  310  in the carrier  330  while allowing the handle to be hooked to a connection  335  extending from bracket  334 . Bracket  334 , in turn, is coupled to the transport path of system  300  in a manner that allows the carrier to be transported. For example, the bracket  334  can be coupled to bolts  339  which in turn are coupled to the chain driven along internal rails  321 ,  322 ,  323  and  324  and gears. It should be noted that carrier  330  can be shaped and connected to the transport system in other ways. For example,  FIG. 3A ( 8 ) illustrates a carrier  600  without a metal handle. Instead, a solid back  601  has an opening  602  for a bolt that, in turn, can be coupled to a chain.  
         [0054]     The carrier  330  further comprises guide elements  336  and  338  connected to the basket  331  by brackets  333  and  337  respectively. The guide elements follow the guide rails  320  as illustrated in  FIG. 3D  to keep the carrier on the transport path.  
         [0055]      FIGS. 3F through 3M  illustrate different views and cross-sectional views of the structural support and motor mechanism of the alternative embodiment.  
         [0056]     In  FIG. 3F , the structural support comprises of a plurality of rectangular beams  360  connected together to form a frame. The structural support on the front or rail ( 320 ) side is defined by vertical beams  361  and  362  connected by horizontal beams  363  and  364  to form a front or rail side rectangular frame. On the rear side, the structural support is defined by vertical beams  365  and  366  connected by horizontal beams  367  and  368  to form a rear side rectangular frame. The front or rail side rectangular frame and the rear side rectangular frame are connected by a series of shorter beams, including beams  369 ,  370 ,  371  and  372  to form a volumetric rectangular space. The frame can have cover supports  450  as illustrated in  FIG. 3A ( 5 ).  
         [0057]     The motor mechanism  400  is positioned within the rectangular space. The motor mechanism comprises four gears  401 ,  402 ,  403  and  404  and a motor  405  (not fully illustrated) supported by motor base bracket  406 . Each gear comprises a gear element, a shaft connected to the gear element and a bracket  500  connected to a shaft and a plate for positioning and supporting the gear element. Further views of an exemplary idler bracket are provided in FIGS.  3 A( 2 ) and  3 A( 14 ). The motor  406  drives the carriers along the internal rails  321 ,  322 ,  323  and  324  and gears  401 ,  402 ,  403  and  404 .  
         [0058]      FIG. 3G  shows a front view of the frame of  FIG. 3F .  FIG. 3G  illustrates the front or rail side rectangular frame defined by beams  361 ,  362 ,  363  and  364 . As further illustrated in  FIG. 3G , the internal rails  321 ,  322 ,  323  and  324  are positioned approximately at the center of the rectangular frame. The distance H 3  from rail  364  to motor base bracket  406  can be 10 inches.  
         [0059]     Although not shown in  FIG. 3G , the internal rails  321 ,  322 ,  323 , and  324  are positioned within the volumetric rectangular frame. The frame has cut-out sections in which a given internal rail is placed. The distance H 1  from the inner edge of beam  363  to a cut-out above internal rail  324  can be 1 foot, 5¾ inches. The distance H 2  from the inner edge of beam  364  to a cut-out below rail  323  can be 1 foot, 7¾ inches. Similarly, the distance W 1  from the inner edges of vertical beams  361  and  362  to cut-outs on the outer sides of rails  321  and  322  respectively can be 9½ inches. The distance W 2  between the cut-outs on the inner sides of rails  321  and  322  can be 2 feet, 3 inches.  
         [0060]      FIG. 3H  illustrates a top view of the frame of  FIG. 3F .  FIG. 3H  illustrates the volumetric rectangular frame is formed in part by connecting beams  363  and  367  to beams  371  and  372 . The distance D 1  between the inner edges of beams  363  and  367  can be 9¼ inches.  
         [0061]     As discussed above with respect to  FIG. 3G , internal rails  321 ,  322 ,  323  and  324  are positioned within the volumetric rectangular frame.  FIG. 3H  illustrates this feature with respect to rails  321  and  322 . Rails  321  and  322  are positioned internal to beam  363 .  
         [0062]      FIG. 31  illustrates a side view of the frame of  FIG. 3F . This view shows that the right side of the volumetric rectangular frame is formed by connecting beams  361 ,  363 ,  364 ,  366 ,  367 ,  368 ,  370  and  372  together. The distance D 2  from the outside edge of beam  363  to the outside edge of beam  367  can be 11¾ inches. This is ¼ inch less than the distance D illustrated in  FIG. 3D , because it does not include the depth of sliding doors  350 .  
         [0063]     As discussed above with respect to  FIG. 3G  and  FIG. 3H , internal rails  321 ,  322 ,  323  and  324  are positioned within the volumetric rectangular frame.  FIG. 31  illustrates this feature with respect to rails  323  and  324 . Rails  323  and  324  are positioned internal to beam  361 .  
         [0064]      FIG. 3J  illustrates a top cross-sectional view of the frame of  FIG. 3G  along the A-A line of  FIG. 3G . The motor base bracket  406  is not positioned to be equidistant from beams  369  and  370 . Rather, the distance W 3  between the outer edge of beam  370  and one edge of the bracket  406  can be 10¼ inches while the distance W 6  between the outer edge of beam  369  and the other edge of bracket  406  can be 1 foot, 7¾ inches. The bracket  406  is supported by six vertical beams  380 ,  381   382 ,  383 ,  384  and  385 . Beams  380  and  385  do not extend vertically above bracket  406  as illustrated in  FIG. 3F . The length W 7  of the bracket  406  can be 2 feet, 1 inch. As illustrated in  FIG. 3J  and  FIG. 3G , the supporting beams are not placed at equal distances along the bracket  406 . The distance W 4  from the inner edge of beam  383  to one edge of beam  384  can be 8¼ inches. In contrast, the distance W 5  from the other edge of beam  384  to the inner edge of beam  385  can be 1 foot, 1 inch.  
         [0065]      FIG. 3K  illustrates another top cross-sectional view of the frame of  FIG. 3G  along the B-B line of  FIG. 3G . Rails  321  and  322  are connected to beams  396  and  395  respectively. Beam  396  supporting rail  321  is connected directly or indirectly to a square-shaped group of beams  391 ,  392 ,  393  and  394 . Similarly, beam  395  supporting rail  322  is connected directly or indirectly to a square-shaped group of beams  387 ,  388 ,  389  and  390 .  
         [0066]     Each of the square-shaped group of beams provides the top cover of a partial cube of beams that support and cover the gears  403  and  404  as illustrated in  FIG. 3F . The dimensions and placement of the square-shaped group of beams is illustrated in  FIG. 3K . The internal depth D 3  of each square-shaped group can be 7½ inches. Each square-shaped group of beam can be positioned to be 10½ inches (W 9  in  FIG. 3K ) from the inner edges of side beams  369  and  370 . The outer and inner distances W 8  and W 10  between the two group of beams can be 1 foot, 3½ inches and 1 foot, 1 inch respectively.  
         [0067]      FIG. 3K  highlights the internal placement of rails  321 ,  322  and  323  within the rectangular volumetric frame. As discussed above with respect to  FIG. 3G , the internal placement is achieved through cut-out portions in the external rectangular volumetric frame.  FIG. 3K  illustrates the depth of the cut-out portion vis-à-vis horizontal rail  323 . The distance D 4  between the outer edge of the volumetric frame and the back edge of rail  323  can be 1¾ inches.  
         [0068]      FIG. 3L  illustrates another top cross-sectional view of the frame of  FIG. 3G  along the C-C line of  FIG. 3G .  FIG. 3L  illustrates that the internal rails, such as  321  and  322 , remain internal to the rectangular volumetric frame in the region between the lower gears  403  and  404  and the upper gears  401  and  402  (illustrated in  FIG. 3F ). With internal rails, the frame has a series of beams that do not span the entire width of the frame. For example, beam  398  has a width W 11  of 2 feet, 3 inches, which is less than half of the entire width W of the frame.  
         [0069]      FIG. 3L  also illustrates that support for the beams  395  and  396  which support the internal rails is provided by horizontal beam  399 . Beam  399  has a longer width than beam  398 . The width W 10  of beam  399  can be 2 feet, 5 inches.  
         [0070]      FIG. 3M  illustrates a side cross-sectional view of the frame of  FIG. 3H  along the D-D line of  FIG. 3H .  FIG. 3M  illustrates that a series of cross-beams, such as beams  410 ,  412 ,  413  and  414  are used to support the frame. These beams, however, are not positioned at equal distances from the top of the frame to the bottom of the frame. The distance H 5  from the top of the frame to the top edge of beam  410  can be 1 foot, 4½ inches while the distance H 7  from the bottom of the frame to the bottom edge of beam  414  can be 1 foot, 6½ inches. The distance H 4  between beams  412  and  413  can be 2 feet, 1 inch.  
         [0071]      FIG. 3M  illustrates that internal rails  321 ,  323  and  324  within the volumetric rectangular frame. The vertical distance H 6  between the outer edges of the beams supporting the internal rail  323  and  324  is 5 feet, 10 inches. As discussed above, each of the gears  401 ,  402 ,  403  and  404  are positioned within a partial cube of beams.  FIG. 3M  illustrates one view of these partial cubes of beams. For example, beam  394  discussed with respect to  FIG. 3K  is illustrated as comprising one of beams in the group for gear  404 , while beam  411  comprises one of the beams in the group for gear  401 .  
         [0072]     It should be understood to one skilled in the art that multiple methods of construction may be employed to achieve the same functionality and result of the alternative embodiment.  
         [0073]     Although the present invention has been fully described in connection with the embodiments thereof and with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood as being included within the scope of the present invention as defined by the claims.