Patent Publication Number: US-2022234636-A1

Title: Cart with cabinet closure

Description:
FIELD OF THE INVENTION 
     In one aspect, the invention relates to a rolling cart. In another aspect, the invention relates to a closure for a rolling cart. In a further aspect, the invention relates to a fastening system for attaching a closure to a rolling cart. 
     BACKGROUND OF THE INVENTION 
     Assembled work carts are bulky items to keep in a sales inventory. Separately stocking easy-to assemble carts in boxed kits and easy-to-mount accessories for the carts in boxed kits saves in storage and offers customers the capability to easily customize a work cart to their needs. 
     OBJECTS OF THE INVENTION 
     It is an object of this invention to provide a cabinet closure system for a work cart that is easy to inventory, ship and mount to the cart. 
     It is another object of this invention to provide a work cart that is adapted for easy mounting of the cabinet closure system. 
     It is another object of this invention to provide a bushing to modify the cart to receive the cabinet closure system. 
     SUMMARY OF THE INVENTION 
     One embodiment of the invention provides a hand cart comprising a bottom tray, a top tray, legs having apertures connecting the bottom tray and the top tray, and casters supporting the bottom tray. The bottom and top trays are generally rectangular and have four corners. The aperture legs are four in number and formed from angle-stock. The legs connect the four corners of the bottom tray with the four corners of the top tray to form a rigid rectilinear structure. The casters are four in number are connected to the four corners of the bottom tray. They extend away from the top tray. Each of the angle-stock legs comprises an elongated first plate portion and an elongated second plate portion connected along a corner. The elongated first plate portion and the elongated second plate portion have parallel front and back faces. Each elongated plate portion defines at least one non-cylindrical aperture, preferably keyhole-shaped, extending therethrough generally normal to the front face and back face. 
     Another embodiment of the invention provides a kit that can be used for closing off the volume between the top and bottom trays of the just-described hand cart for more secure storage of items on the bottom tray. The kit comprises a first wall section, a second wall section, and a third wall section. The first wall section is generally flat. The second wall section has a first generally flat section and a second generally flat section connected by a corner section. The third wall section has a first generally flat section and a second generally flat section connected by a corner section, and a generally flat door section connected to the second generally flat section by a hinge. 
     Including corners on the wall sections permits the closure to comprise only three separate pieces and facilitates installing the pieces on the work cart. 
     Another embodiment of the invention provides a bushing that can be used with the just described cart as well as with the kit. The bushing has a generally flat first end and an oppositely facing generally flat second end, a longitudinal axis, and a passage extending therethrough from the first end to the second end along the longitudinal axis. The bushing has a first end portion adjacent the first end and a second end portion adjacent the second end. The first end portion is of a larger dimension transverse to the longitudinal axis than the second end portion. The second end portion of the bushing has an upper portion and a lower portion. The upper portion of the second end portion of the bushing has a generally cylindrical peripheral surface and the lower portion of the second end portion of the bushing forms a pair of wall sections that extend downwardly from the upper portion of the second end portion of the bushing. The lower end of each wall section is chamfered. The passage extending from the first end to the second end of the bushing is generally rectangular in elevation view and is vertically elongated. 
     The bushing is well adapted to use with the previously described hand cart when the non-cylindrical apertures are keyhole shaped to assist in securing the wall sections to the cart. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a pictorial view of a hand cart according to one embodiment of the invention. 
         FIG. 2  is a reverse view of the hand cart shown in  FIG. 1 . 
         FIG. 3  is an exploded view of a kit to enclose a portion of the hand cart shown in  FIGS. 1 and 2 . 
         FIG. 4  is a pictorial view of a cart as in  FIG. 2  onto which the kit of  FIG. 3  has been installed. 
         FIG. 5  is a reverse view of the cart of  FIG. 4 . 
         FIG. 6  is a pictorial view of a bushing for use with the carts of  FIGS. 1-5  from a back side. 
         FIG. 7  is a view of the bushing of  FIG. 6  from the front side. 
         FIG. 8  is an exploded pictorial view of a portion of the cart shown in  FIG. 4  and  FIG. 5  showing construction details. 
         FIG. 9  is an elevation view of a portion of the cart shown in  FIG. 4  and  FIG. 5  showing design details. 
         FIG. 10  is a cross-sectional view of the portion of the cart shown in  FIG. 9  taken along lines  10 - 10  of  FIG. 9 . 
         FIG. 11  is an exploded pictorial view of a portion of a cart similar to  FIG. 8  but with round boreholes in the legs. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     One embodiment of the invention provides a hand cart  12  comprising a bottom tray  14 , a top tray  16 , legs  18 ,  20 ,  22 ,  24  having apertures  26  connecting the bottom tray and the top tray, and casters  28 ,  30 ,  32 ,  34  supporting the bottom tray. The bottom and top trays are generally rectangular and have four corners. The apertured legs are four in number and formed from angle-stock. The legs connect the four corners of the bottom tray with the four corners of the top tray to form a rigid rectilinear structure. The casters are four in number are connected to the four corners of the bottom tray. They extend away from the top tray. Each of the angle-stock legs comprises an elongated first plate portion  36  and an elongated second plate portion  38  connected along a corner  39 . The elongated first plate portion and the elongated second plate portion have parallel front and back faces. Each elongated plate portion defines at least one non-cylindrical aperture  26  extending therethrough generally normal to the front face and back face. In a preferred embodiment, each non-cylindrical aperture has an upper end and a lower end and is generally keyhole-shaped with a generally round hole  40  at the upper end and a slot  42  extending downwardly from the hole to the lower end. 
     Preferably, the top generally rectangular tray has a first end  44  and a second end  46 . The hand cart further comprising a handle structure  49  attached to the first end of the top generally rectangular tray. 
     Also preferably, the top generally rectangular tray and the bottom generally rectangular tray each have peripheral side walls extending upwardly and downwardly from each of the top generally rectangular tray and the bottom generally rectangular tray. The peripheral side walls provide structural rigidity and a contact surface for the enclosing side walls when present. The bottom tray is accessible from an outside of the hand cart when the wall sections are not present. The trays and legs can be formed from any suitable material, but structural foam has been used with good results. For example, foamed polypropylene has been used with good results. 
     When desired, bushings provide structure to mount enclosing wall sections to the cart. Each bushing  48  preferably a generally flat first end  50  and an oppositely facing generally flat second end  52  and a passage  54  extending therethrough from the first end to the second end. The bushing has a first end portion  56  that won&#39;t pass through the at least one non-cylindrical aperture and a second end portion having a outside peripheral surface  58  that closely passes through an inside peripheral surface of the at least one non-cylindrical aperture. Each bushing is positioned in an aperture with the second end surface slightly protruding beyond the front face of a plate portion and the first end portion contacting the back face of the plate portion. 
     In an embodiment which has been used with good results, each keyhole-shaped aperture, when viewed in elevation, has a generally circular upper portion and a generally rectangular lower portion extending radially downwardly from the generally circular upper portion. The apertures preferably taper toward the front face portion of the angle stock legs and the bushings contact the aperture walls at the narrowest point. Each bushing has a generally flat first end and an oppositely facing generally flat second end and a passage extending therethrough from the first end to the second end. The bushing has a first end portion that won&#39;t pass through the at least one non-cylindrical aperture and a second end portion having an outside peripheral surface that closely passes through an inside peripheral surface of the at least one non-cylindrical aperture. Each bushing is positioned in the at least one aperture with the second end surface slightly protruding above the front face of a plate portion and the first end portion contacts the back face of the plate portion. The second end portion of each bushing has an upper portion and a lower portion. The upper portion has a generally cylindrical peripheral surface fitting closely against the wall defining the circular upper portion of the aperture. The lower portion of the bushing comprises a pair of wall sections each having an upper end and a lower end extending downwardly from the upper portion and biasing against the pair of inside walls defining the generally rectangular portion of the keyhole shaped passage to frictionally and/or by interference fit hold the bushing in the passage. The lower end of each wall section is chamfered. The passage through each bushing is preferably generally rectangular in elevation view and is vertically elongated. The first end portion of each bushing has a generally oval shaped cross section and is vertically elongated. See  FIG. 9 . The legs of the bushings fit into the lower portions of the keyholes to retain the bushings in the keyholes and to orient the major axes of the rectangular passages through the bushings up and down. 
     A kit that can be separately manufactured, shipped and installed, to enclose the volume of a cart between the trays comprises a first wall section  60 , a second wall section  62 , and a third wall section  64  that can be attached to the four angle stock legs and to form a closure bounded by the upper tray, the lower tray, and the first, second and third wall sections, and the angle stock legs. The angle stock legs can have round or non-cylindrical apertures, so long as the bushings are sized to fit. The wall sections are preferably formed of sheet metal. In accordance with the invention, a four-sided closure for the cart can be formed from three wall section, and by keeping a wall section by the included corners narrow, the kit can be shipped in a relatively flat box. 
     In a preferred embodiment, the first wall section is generally flat. The second wall section has a first generally flat section  66  and a second generally flat section  68  connected by a corner section  70 . The third wall section has a first generally flat section  72  and a second generally flat section  74  connected by a corner section  76 , and a generally flat door section  78  connected to the second generally flat section by a hinge  80 . 
     Each wall section is attached to two angle-stock legs with fasteners  82 . See  FIG. 10 . Preferably, each fastener passes through a passage  84  in the wall section and though a passage through a bushing positioned in a non-cylindrical aperture. 
     Preferably, each passage through the wall section is horizontally elongated and the passage through the bushing is vertically elongated. The fastener comprises a bolt  86  and a nut  88 . The head of the bolt is urged against a wall section and the nut is urged against the first end portion of the bushing. An edge of the door section opposite the hinge closes against the second flat section of the second wall section. 
     Another embodiment of the invention provides kit that can be used for closing off the volume between the top and bottom trays of the just-described hand cart for more secure storage of items on the bottom tray. The kit comprises a first wall section, a second wall section, and a third wall section. The first wall section is generally flat. The second wall section has a first generally flat section and a second generally flat section connected by a corner section. The third wall section has a first generally flat section and a second generally flat section connected by a corner section, and a generally flat door section connected to the second generally flat section by a hinge. The kit preferably comprises a plurality of fastener pairs for attaching the wall sections to the angle-stock legs. Preferably, each fastener pair comprises a bolt and a nut, and the kit further comprises a bushing for each fastener pair. 
     Another embodiment of the invention provides a bushing that can be used with the just described cart as well as the kit. The bushing has a generally flat first end and an oppositely facing generally flat second, a longitudinal axis, and a passage extending therethrough from the first end to the second end along the longitudinal axis. The bushing has a first end portion adjacent the first end and a second end portion adjacent the second end. The first end portion is of a larger dimension transverse to the longitudinal axis than the second end portion. The second end portion of the bushing has an upper portion and a lower portion. The upper portion of the second end portion of the bushing has a generally cylindrical peripheral surface and the lower portion of the second end portion of the bushing forms a pair of wall sections each having an upper end and a lower end that extend downwardly from the upper portion of the second end portion of the bushing. The lower end of each wall section is chamfered. The passage extending from the first end to the second end of the bushing is generally rectangular in elevation view and is vertically elongated. Preferably, the first end portion of the bushing has an oval shaped cross section and is vertically elongated to facilitate inserting the bushings into their receiving passages by hand. 
     Another embodiment of the invention is illustrated in  FIG. 11 . The bushing  48  can be used to secure the wall sections to legs having round apertures  26  so long as the second end  52  of the bushing has a transverse dimension small enough to pass through the aperture. Preferably, the bushing fits snugly in the aperture and the second end  52  of the bushing has a longitudinal dimension slightly greater than the thickness of the leg plate portion  36  so that the wall section will pull up close to the leg. 
     While certain preferred embodiments have been described herein, the invention is not to be construed as being so limited, except to the extent that such limitations are found in the claims.