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CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     This application is a division of our co-pending application, entitled MOVEABLE SHELF AND PARTITIONING SYSTEM, Ser. No. 10/248,686, filed Feb. 9, 2003 and assigned to the assignee hereof. 
     
    
     DETAILED DESCRIPTION  
       [0002]     This invention relates to a moveable shelf and support therefore that offers greater flexibility and versatility than those presently in use.  
         [0003]     There are known storage systems that include one or more moveable shelves that are supported for movement along a work area on tracks or guide rails that are affixed to the floor of the area. When there are a plurality of these shelves, they can be compressed in abutting relationship to open up space and then moved to offer access to the individual shelf areas for the insertion and removable of articles therefrom. These types of devices have wide application and considerable utility.  
         [0004]     However, the requirement for having rails or tracks in the floor by which the shelves can be moved means that the area must be specially adapted to utilize this type of system. Also, once converted to this arrangement, the utility of the area is somewhat compromised.  
         [0005]     In addition, once in position the types of moveable shelves aforedescribed are not easily moved to another location. If they are to be moved, then that location must also be modified to provide the necessary guide rails on which the shelves can be mounted.  
         [0006]     It is, therefore, a principal object to this invention to provide an improved moveable shelf arrangement that does not require guide rails for its operation.  
         [0007]     It is a further object to this invention to provide a moveable shelf that can be supported on any type of floor and can be freely moved from position to position to optimize space utilization.  
         [0008]     It is a still further object of the invention to provide an improved moveable base system for such shelves that will offer a predictable movement along a floor of any conventional type including carpeted ones that will insure parallel movement of the individual shelves.  
       SUMMARY OF THE INVENTION  
       [0009]     A first feature of the invention is adapted to be embodied in a storage arrangement comprising a shelf adapted to receive articles. The shelf has a base and a drive unit disposed beneath the base and adapted to support the shelf on a floor for movement there along. Each drive unit is comprised of pairs of transversely spaced wheels supported for rotation upon the base about parallel, spaced axes. Each drive unit includes a support belt trained around the wheels and having a lower flight for engaging the floor and supporting the shelf thereupon. At least drive unit further includes a drive for rotating at least one of the wheels for driving the belt and effecting movement of the shelf along the floor. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0010]      FIG. 1  is a side elevational view of a moveable partitioning and shelving system constructed in accordance with a first embodiment of the invention.  
         [0011]      FIGS. 2, 3  and  4  are bottom views of the supporting frame for the shelf shown in  FIG. 1  looking at the left-hand edge, the center and the right-hand edge, respectively.  
         [0012]      FIGS. 5, 6  and  7  are side elevational views of the frame supporting portion showing the same areas illustrated in  FIGS. 2, 3  and  4 , respectively.  
         [0013]      FIG. 8  is a top plan view showing two pairs of drive belts.  
         [0014]      FIG. 9  is a side elevational view of the drive belts.  
         [0015]      FIG. 10  is a view, in part similar to  FIG. 9 , but only shows one drive belt and in another type of arrangement therefore.  
         [0016]      FIG. 11  is a cross sectional view taken along the line  11 - 11  of  FIG. 10 .  
         [0017]      FIG. 12  is a view, in part similar to  FIG. 9 , and shows another embodiment of the invention and illustrates the arrangement supported on the floor.  
         [0018]      FIG. 13  is a graphical view showing how the driving load depends upon the width of the drive belt.  
         [0019]      FIG. 14  is an enlarged view, in part similar to  FIG. 10 , and shows how the drive belt supports the shelving and acts as a cushion between the driving wheels and the floor.  
         [0020]      FIG. 15  is a view, in part similar to  FIG. 3 , but shows another embodiment of the invention.  
         [0021]      FIG. 16  is a view looking in the direction of the arrow  16  in  FIG. 15 .  
         [0022]      FIG. 17  is a view looking the direction of the arrow  17  in  FIG. 15  and is in part similar to  FIG. 6 . 
     
    
     DETAILED DESCRIPTION  
       [0023]     Referring now in detail to the drawings and initially to the embodiment of  FIGS. 1 through 9  and beginning by specific reference to  FIG. 1 , a moveable shelf constructed in accordance with this embodiment of the invention is identified generally by the reference numeral  31 . The moveable shelf  31  is adapted to be supported for movement along a floor  32  of any common type in a manner to be described.  
         [0024]     The shelf  31  includes an upper shelf assembly  33  that is mounted on a base, indicated generally by the reference numeral  34 . The shelf assembly  33  can be of any material and construction and, for example, can include adjustable shelves that are held by side pieces. Since those skilled in the art will readily understand the various forms that the shelving may take, further description of that is believed to be unnecessary.  
         [0025]     The base  34  has a construction as best shown and as will be described later by reference to  FIGS. 2 through 7 . However, it includes driving wheels  35  and driven wheels  36  that are interconnect by an endless belt  37  which provides the direct support for the shelf  31  on the floor  32 .  
         [0026]     Referring now primarily to  FIGS. 2 through 6 , the base  34  is comprised of a sheet metal assembly comprised of a planar type upper surface  38  and a pair of folded down side surfaces. Reinforcing U-channels  39  may be affixed at spaced locations along the horizontal surface  38  to add rigidity to the construction. A driving shaft  41  and driven shaft  42  are journaled in spaced transverse relationship by means of a plurality of pillow blocks  43  that are affixed to and form a part of the base  34 . Specifically, these pillow blocks  43  are fixed to the under side of the panel surface  38 . Bearings  44  carried by these pillow blocks  43  complete the journaling of the shafts  41  and  42  in the base  34 .  
         [0027]     The driving wheels  35  are affixed at spaced locations and between pairs of the pillow blocks  43  and bearings  44  to the driving shaft  41 . In a like manner, the driven wheels  36  are affixed to the driven shaft  42 . In order to facilitate assembly and machining, the shafts  41  and  42  need not be continuous shafts but can constitute shaft segments that are joined together by couplings  45 .  
         [0028]     The drive belts  37  may be of the toothed type and can cooperate with sprocket teeth on the driving wheels  35  and driven wheels  36 . In addition and if desired, a plurality of sprockets  46  may be fixed along the lengths of the shafts  41  and  42  and interconnected by a chain (not shown).  
         [0029]     The driving shaft  41  is driven by one or more electric motors  47  that are mounted on a mounting bracket assembly  48  on the underside of the plate  38 . These electric motors  47  have pinion gears  49  affixed to their drive shafts. The pinion gears  49  cooperate with gears  51  fixed to the driving shaft  41  so as to drive it. These motors  47  are of the reversible variable speed type and are control by a suitable control panel  49  mounted on the side of the shelves  31  ( FIG. 1 ).  
         [0030]     Although the drive belts  37  may be made of any suitable material and may, as noted above, have their inner flight toothed to provide a non-slip driving relationship with the driving wheels  35  and driven wheel  36 , it may be desirable to provide an arrangement for retaining the drive belt against axial movements.  FIGS. 10 and 11  show an embodiment to how this may be accomplished. Aside from this anti-slipping arrangement, the construction is the same as that previously described and, therefore, the components which are the same have been identified by the same reference numerals and will not be described again, except insofar as is necessary to understand the construction and operation of this embodiment.  
         [0031]     In this embodiment, the driving and driven wheels  35  and  36  have annular members  51  affixed to their outer periphery and which extend radially outwardly beyond the outer periphery of the wheels  35  and  36 . Thus, as seen in  FIG. 1 , these extending portions provided by the annular members  51  will insure that the belts  37  are maintained in axial position on the wheels  35  and  36 .  
         [0032]     Depending upon the width or depth of the shelves  31 , it may be desirable to provide further support on the floor  32  and specifically for the back up side of the belt  37 .  FIG. 12  shows such an arrangement where, in addition to the driving wheel  35  and driven wheel  36  mounted on the shafts  41  and  42 , respectively, there are a plurality of back up rollers  61  that are carried by shafts  62  that are journaled in the pillow blocks  43  and bearings  44 . Thus, more back up contact is provided between the drive belt  37  and the floor  32 .  
         [0033]     Also, the width of the belts  37  may be changed from a narrow width to a wide width as shown in  FIG. 13  where the different widths are shown at  37   a ,  37   b  and  37   c . Although the support is greater when the width is increased, this provides a larger resistance to driving and requires larger driving motors.  
         [0034]      FIG. 14  shows how the inter-positioning of the belt  37  between the driving and driven wheels  35  and  36  and the floor  32  provides a cushioning between the wheels  35  and  36  and the floor  32 . Hence, the device can be utilized on a wide variety of floor materials and, special rails embedded in or mounted on the floor  32  are not required. The supporting portion of the drive belt is indicated in  FIG. 14  by the reference numeral  63 .  
         [0035]     It has been noted in the embodiment as thus far described, there are provided two electric drive motors  47  spaced transversely across the length of the shelf  31 . Of course, the number of drive motors can be changed. Also although electric motors are illustrated, other means for rotating the driving shaft  41  can be employed. These can include providing a manual crank handle mounted on the side of shelf  31  for rotating the shaft  41 .  
         [0036]     In the embodiment as thus far described, all of the drive wheels  35  are mounted on a common shaft and are driven. Depending upon the loads to be expected and the specific environment, it is not necessary that all wheels be directly driven.  
         [0037]      FIGS. 15 through 17  are partial views which can be considered to be similar to  FIGS. 3 and 6  and show how some wheels, again indicated by the reference numerals  35  and  36 , can be mounted on stub shafts  81  which are journaled in the pillow blocks  43  and bearings  44 . In this case, these drive belts  37  are only driven through their contact with the floor.  
         [0038]     In connection with an arrangement wherein the driving wheels that are driven by an electrical motor or other force are not all coupled to each other, it would be possible to provide controls whereby one motor can be driven and the other remains stationary or is rotated in a reverse direction. In this way, it is actually possible for the shelf to be driven in an arcuate fashion. The possibilities of such various movements should be readily apparent to those skilled in the art without further description or illustration.  
         [0039]     Thus, from the foregoing description it should be readily apparent that the described embodiments permit the use of storage devices that can be easily moved and employed in any closed area without the necessity of guide rails. This offers substantially greater versatility and a wider variety of types of storage systems. Of course, the foregoing description is that of preferred embodiments of the invention and various changes and modifications may be made without departing from the spirit and scope of the invention, as defined by the appended claims.

Summary:
A number of embodiments of moveable storage racks and/or partitions that can be installed in existing buildings without the necessity of installing guide rails for them. In addition, the movement may be controlled so that the partitions move either in a parallel fashion or they can be rotated through an arc. The partitions are supported on drive and guide belts that are mounted on the underside thereof and which eliminate the need for the guide rails and spread the weight of the partition over a greater area of the floor so as to permit use in buildings which were not originally designed for such systems.