CART ASSEMBLY

Abstract: A cart structure is provided in which generally rectangular top (24) and bottom panel (20) assemblies are clamped against the top and bottom of end panels (15, 16) by draw rods which pass through spacer tubes. The draw rods (22) extend from a tightening head upwardly through a bottom panel assembly and end panels to make a screw connection in nut inserts in the top panel assembly. The bottom panel assembly includes a rigid carriage frame to which caster wheel units (38) are mounted.

Description: Description CART ASSEMBLY Technical Field The present invention relates to vending and collection carts for use in material handling systems, such as, for example, the system for hotels and the like described in my copending application Serial No. 237,155, filed August 26, 1988, in which the carts are adapted to receive various removable containers, shelves, and bins. Background of the Invention There is a need for vending and collection carts for use in hotels by room attendants and food service personnel which are easy to use and maneuver, are readily cleanable and maintainable, are adapted to receive modular containers and shelves in a variety of arrangements, are easily assembled and reconfigured, have a furniture-grade appearance, and have excellent bumper protection against damage by accidental impact with walls or furniture Summary of the Invention In meeting the aforesaid needs, a cart structure is provided in which generally rectangular top and bottom panel assemblies are clamped against the top and bottom of end panels by draw rods which pass through spacer tubes. The draw rods extend from a tightening head upwardly through a bottom panel assembly and end panels to make a screw connection in nut inserts in the top panel assembly. The bottom panel assembly includes a rigid carriage frame to which caster wheel units are mounted. Tightening of the draw rods is limited by engagement of the ends of spacer tubes with the carriage frame and nut inserts. Preferably, the panel components of the cart are unitary, blow-molded parts filled with plastic foam. In the vending version of the cart, the front can be closed by a tambour door which is vertically guided at the front and back of the cart by guideways in the end panels which continue downwardly from a horizon¬ tal passageway provided by the top panel assembly. The end panels and an optional removable center divider panel have horizontal slideways spaced apart a modular distance to receive support lips on removable contain¬ ers, totes, and shelves. In the collection version of the cart, there is a swing-out removable bin and a top drawer. Upper and lower horizontal " bumper frames of resilient material are provided to protect against damage by accidental contact of the cart with other objects. These frames are clamped in position as parts of the top and bottom panel assemblies. Brief Description of the Drawings Figure 1 is a perspective view illustrating vending and collection carts made in accordance with the present invention, and showing examples of various containers to be used therewith; Figure 2 is a perspective view of the vendor cart with the tambour door in closed position; Figure 3 is an exploded perspective view of the components of the bottom subassembly for the cart; Figure 4 is an exploded perspective view of the top components of the cart; Figure 5 is an exploded perspective view showing the top and bottom units assembled, and the end panels, back panels, inner top panel, and tambour door oriented for assembly; Figure 6 is an exploded, fragmentary, vertical sectional view at a bottom corner portion of the cart; Figure 7 is an exploded, fragmentary sectional view of a top corner portion of the cart; Figure 8 is a transverse, fragmentary, vertical sectional view of a forward portion of the cart; Figure 9 is a detail, vertical sectional view taken as indicated by line 9-9 in Figure 8; Figure 10 is an elevational view of a bottom portion of one of the end panels as viewed from the inside of the cart; Figure 11 is a bottom plan view of one of the end panels; Figure 12 is a fragmentary top plan view of the bottom panel; and Figure 13 is a detail, fragmentary, horizontal sectional view of the back panels taken as indicated by line 13-13 in Figure 5. Detailed Description of the Invention Referring to the drawings, it is seen that a vendor cart 8 in accordance with the present invention has a top unit 10, tambour door 12, inner top panel 14, end panels 15-16, center divider panel 17, back panels 18-19, and bottom unit 20 which are clamped together by four vertical draw rods 22 passing through spacer tubes 23 adjacent the corners of the cart. The top unit 10 comprises an outer top panel 24, top bumper frame 26, and front and back guide rails 27-28; and the bottom unit 20 comprises a bottom panel 30, bottom bumper frame 32, four corner inserts 34, and a carriage having a frame 36 and four caster wheel units 38. Directing attention to the bottom panel 30, the upper side thereof is formed with a back longitudi¬ nal groove 30a, end grooves 30b, and a front longitudi- nal raised curb 30c having a central cutout. The back and end grooves 30a, 30b terminate at front and back raised wall portions 30d at the top of rounded corner extensions. These raised wall portions 30d are connected by end curbs 30e, which, together with end ridges 3Of, define the end grooves 30b. The back groove 30a is defined by a back ridge 30g and a sloped ridge 3Oh at the front. A central keyway slot 30i extends partway across the width of the bottom panel. On its underside, the bottom panel 30 has a rectangular depend¬ ing central section 30j surrounded at the top by a continuous downward facing wall 30k. This wall 30k merges with an outer wall 30m, at the top of which there is a border flange 3On presenting a downwardly facing circumferential groove 3Op. The bottom bumper 32 is a molded, resilient, urethane part shaped to contour to the periphery of the bottom panel 30 and having an upper rib 32a formed to fit into the groove 3Op of the bottom panel. This upper rib 32a is inset from a vertical bumper wall 32b such that the outer face of the bumper wall is spaced outwardly slightly with respect to the periphery of the bottom panel 30. Projecting inwardly from the vertical bumper wall 30b are front and back flanges 32c and end flanges 32d resting on the carriage frame 36. These flanges 32c, 32d and the vertical wall 32b preferably have perforated metal inserts 40 for stiffening. At the corners, the bottom bumper 32 has contoured extensions 32e which match the corner extensions 30d of the bottom panel 30. The corner inserts 34 fit into the underside of the end extensions 32e of the bottom bumper 32 as backing for the corners thereof. The carriage frame 36 is generally rectangular and surrounds the central depending section 30j of the bottom panel. Corner mounting plates 37 are fixed on the underside of the carriage frame for receiving the caster wheel units 38. Screws secure the bumper flanges 32c-32d, corner inserts 34, and carriage frame 36 to the bottom panel 30. Preferably, the bottom panel is molded with nut inserts for the screws. The corner mounting plates 37 have extension portions 37a projecting outwardly from the carriage frame 37 to underlie the corner inserts 34. The end panels 15, 16 are formed with integral corner columns 16a which surmount the corner extensions of the bottom panel 30 and have bottom tongues 16b registering with the end grooves 30b of the bottom panel 30. The inner faces of the column portions 16a of the end panels are formed with front and back door guiding channels 16c, 16d and back locking grooves 16e. Inwardly of these locking grooves are a series of horizontal support ribs 16f shaped to provide a series of guideways 16g. Each of these guideways 16g is formed at its front entry end with a front bottom stop and a complementing upper expanded accessway which tapers downwardly at the rear to merge with the remainder of the top wall of the guideways. At their upper end, the end panels are widened by a top rib 16h which is prefer¬ ably formed with a series of upwardly projecting dowels 16i at its upper face. The back panels 18, 19 each have top and bottom lips 18a for interfitting with the inner top panel 14 and the back groove 30a in the bottom panel. They also have end tabs 18c for fitting into the back locking grooves 16e of the end panels 15, 16. At their opposed edges, each back panel is formed with a central trapezoidal shaped extension 18d and an end extension 18e. These extensions are staggered and shaped so that the central extension of each back panel fits between the end extension and central extension of the other back panel. Furthermore, the front face of each exten¬ sion has a longitudinal retaining groove 18f, and the back face of each extension 18d, 18e is recessed through half of its thickness so that the extension has a front lip portion 18g and the lip portions of the extensions overlap complementing recesses formed along the front faces of the back panels between the extensions. With this arrangement, the back panels collectively provide a forwardly facing retaining groove by way of the retaining grooves 18f in the extensions. The underside of the inner top panel 14 is provided near its ends with recessed, tapered seats 14a to receive the dowels 16i at the top of the end panels and has a rear longitudinal groove 14b to receive the lips 18a at the upper end of the back panels 18, 19. The top of the inner panel is formed with end guides 14c and three raised complementing central guides 14d for guiding the tambour door 12. The guides project forwardly at the front ends of the inner top panel as guide extensions. These extensions are complemented by overlying guides 27a presented on the underside of the front and back guide rails 27, 28. Referring to the top subassembly 10, the upper bumper frame 26 has an angle cross section providing a horizontal, inturned anchoring flange 26a and an outer vertical bumper flange 26b. The guide rails 27-28 also have an angle shape in cross section and are adapted to fit within the confines of the front and back sections of the bumper frame 26. Screws anchor the upper bumper frame 26 and guide rails 27-28 to the top panel 14. The tambour door 12 comprises slat members 12a which are generally semicircular in cross-section to provide a rounded outer face and a flat back face. The back faces of the slats are bonded by a suitable adhesive to a flexible, durable fabric backing sheet, such as Mylar. The central divider panel 17 has guideways on its opposite sides matching the guideways 16g on the end panels. It also has top and bottom integral keys 17a, 17b and rear lips 17c. In assembling the cart, the outer top panel 24, top bumper frame 26, and front and back guide rails 27-28 are connected together as a top unit 10 by screws passing through the guide rails and the anchoring flange 26a of the top bumper frame into nut inserts molded into the outer top panel 24. Similarly, the bottom panel 30, bottom bumper frame 32, corner inserts 34, and carriage frame 36 with the caster wheel units 38 bolted thereto are screw-connected together by screws passing through the carriage frame and the bottom bumper flanges 32c, 32d into nut inserts molded into the bottom panel 30. After resilient gasket strips 41, 42 are inserted in the back grooves on the underside of the inner top panel 14 and the upper side of the bottom panel 30, the back panels are interfitted and positioned on the bottom gasket strip 42, with the bottom panel lips fitting into the groove along the gasket strip. The end panels 15, 16 are then interfitted with the end lips 18c on the back panels and seated on the bottom panel 30. The four spacer tubes 23 can then be passed downwardly through registering openings 16x, 3Ox, 32x and 34x in the end panels, bottom panel 30, bottom bumper frame 32, and corner inserts 34 into engagement with the top face of the carriage frame 36 above smaller openings 36x in carriage frame extension 37a. When this is accomplished, the upper ends of the tubes 23 will project above the upper ends of the end panels 15, 16. The inner top panel 14 is then lowered by use of holes 14x over the upwardly projecting portions of the tubes 23 into interfitting engagement with the upper ends of the end panels 15, 16. The tambour door 12 is then placed on the inner top panel, with front and back portions of the door fitting into the front and back door guideways 16c, 16d presented by the end panels 15, 16. The top unit 10 is then lowered into position on the remaining upwardly projecting portions of the tubes 23 by use of the holes 26x in the top bumper frame 26. If the center divider panel 17 is to be used, it is positioned with its bottom key 17a fitting into the slot 30i in the bottom panel 30 and its rear lips 17c fitting into the back central groove 18f presented by back panels before the inner top panel is brought into position and interfits with the top key 17b. As a final step, the draw rods 22 are passed upwardly through the holes 36x in the carriage frame extension 37a register- ing with the tubes 23 and are pushed through the tubes to the nut inserts 40 in the outer top panel 24, where¬ upon the draw rods 22 are threaded into the inserts 40 by application of a wrench to the hexagonal heads 22a on the lower ends of the rods until these heads bear tightly against the underface of the carriage frame extension 37a. Overtensioning of the draw rods is prevented by having the length of the tubes 23 such that the ends of the tubes bear against the nut inserts and the top face of the carriage frame before the flange 26a of the upper bumper 26 and the flanges 32c, 32d of the bottom bumper 32 have been more than slightly compressed. Such compression is advantageous to keep tight engagement of the cart components. Handles 43 may be screw-mounted on the end panels 15-16 at the conclu- sion of the cart assembly or before mounting the end panels. Directing attention to Figures 1 and 14, a collection cart 9 may be constructed in the same manner as the vendor cart 8, with a smaller bottom assembly 10, without an inner top panel 14, and with a one-piece back panel. The end panels are grooved on their inside face at 49 to receive a shelf 50, and the bottom panel is provided with a front stop strip 51. A swing-out bin 52 rests on the bottom panel and has a curved upward edge 52a on its side walls which is of a curvature to engage the underside of the shelf 50 as a stop when the bin is in open position. When the bin is slightly open, it can be lifted over the stop strip 51 for removal of the bin. A top drawer 54 is provided which rests on the shelf 50. As indicated in Figure 1, the vendor cart may be used with a variety of removable container components in the form of totes 60 with swing-up handles 60a, shelves or trays 61, drawers 62, or dispensing drawers 63 with a lowered front wall for easy access. The totes and drawers preferably have a front downwardly curved lip to function as a handle and border lips to engage the support ribs 16f on the end panels 16. When totes 60 narrower than the width between the end panels 16 and center divider panel 17 are to be used, auxiliary supports 70 may be screw-mounted on the underside of the inner top panel 14. These auxiliary supports present support flanges 70a opposite the upper support ribs 16f on the end panels. It will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.

Claims: Claims 1. A cart comprising: a generally rectangular bottom panel assembly having bottom wheel mounts adjacent its corners; a generally rectangular top panel assembly spaced above said base panel assembly; vertical end panels extending between said top and bottom panel assemblies; and draw rod means extending vertically through the entire vertical length of said end panels and engaging said top and bottom panel assemblies for clamping said top panel assembly and base panel assembly against the upper and lower ends, respectively, of said end panels. 2. A cart according to claim 1 in which said top and bottom panel assemblies each have a tongue-and-groove interfit with said end panels. 3. A cart according to claim 2 in which a central vertical divider panel is provided which has a bottom key interfitting with said bottom panel assembly, said divider panel having a tongue-and-groove interfit with said top panel assembly. 4. A cart according to claim 1 in which said draw rod means comprises four rods threaded into said top panel assembly and having an enlarged head bearing against the underside of said bottom panel assembly. 5. A cart according to claim 1 in which said top panel assembly includes a top molded plastic panel having nut inserts molded therein, and said draw rod means comprises rods threaded into said nut inserts and each having an enlarged head bearing against the underside of said bottom panel assembly. 6. A cart according to claim 5 in which spacer tubes surround said rods, said tubes engaging said nut inserts at their upper end and bearing against said bottom panel assembly at their lower end so as to be subjected to compressive forces when said rods are tightened by being turned in said nut inserts to the extent that said top and bottom panel assemblies firmly engage the upper and lower ends of said end panels. 7. A cart according to claim 1 in which said top and bottom panel assemblies include resilient members arranged to be compressed by the clamping action of said draw rod means. 8. A cart according to claim 7 in which said resilient members are horizontal parts of top and bottom bumper units having outward exposed bumper faces. 9. A cart according to claim 1 in which said bottom panel assembly has a bottom rigid caster frame with depending caster units, and said draw rod means comprises draw rods each having an enlarged bottom head bearing against the underside of said carriage frame, said draw rods each being threaded at its upper end into said top panel assembly. 10. A cart according to claim 9 in which spacer tubes surround said draw rods, said tubes engaging the upper side of said caster frame at their lower end and engaging said top panel assembly at their upper end. 11. A cart according to claim 10 in which said draw rods are threaded into nut inserts in said top panel assembly and said spacer tubes engage said nut inserts at their upper end. 12. A cart according to claim 1 in which said top and bottom panel assemblies include externally exposed bumpers. 13. A cart according to claim 12 in which said bumpers comprises bumper frames having horizontal flanges clamped by said draw rod means. 14. A cart comprising: a generally rectangular bottom panel assembly having bottom wheel mounts adjacent its corners; a generally rectangular top panel assembly spaced above said base panel assembly; vertical end panels and a back panel extending between said top and bottom panel assemblies; draw rod means extending vertically through the entire vertical length of said end panels and engaging said top and bottom panel assemblies for clamping said top panel assembly and base panel assembly against the upper and lower ends, respectively, of said end panels and back panel. 15. A cart according to claim 14 in which said top and bottom panel assemblies each have a tongue-and-groove interfit with said end panels and back panel. 16. A cart according to claim 14 in which said back panel has a tongue-and-groove interfit with said end panels. 17. A cart according to claim 14 in which said top and bottom panels each have a tongue-and-groove interfit with said end panels and back panel, and in which said back panel has a tongue-and-groove interfit with said end panels. 18. A cart according to claim 14 in which said cart has a vertical divider panel interfitting with said top and bottom panel assemblies. 19. A cart according to claim 14 in which said cart has a vertical divider panel clamped between with said top and bottom panel assemblies. 20. A cart according to claim 14 in which said top panel assembly provides a passageway open to the front and back for a tambour door, and said end panels provide front and back guideways extending downwardly from the front and back ends of said passageway for guiding side edge portions of a tambour door extending through said passageway. 21. A cart according to claim 20 in which said top panel assembly provides a passageway from front to back; vertical end panels extending between said base panel assembly and top panel assembly and having front and back vertical guideways extending downwardly from said passageway; and a tambour door extending through said passageway into said guideways. 22. A cart according to claim 21 in which a back panel extends between said top panel assembly and bottom panel assembly forwardly of said back guideways of the end panels. 23. A cart according to claim 22 in which back panel means is provided having a tongue-and-groove interfit with said end panels forwardly of said back guideways of the end panels. 24. A cart according to claim 23 in which a vertical divider panel interfits with said bottom panel assembly, top panel assembly, and back panel means. 25. A cart comprising: a generally rectangular bottom panel assembly having bottom wheel mounts adjacent its corner; a generally rectangular top panel assembly spaced above said base panel assembly; and vertical end panels extending between said bottom panel assembly and top panel assembly, said top panel assembly including an outer top panel and an inner top panel defining a passageway therebetween for a tambour door extending from front to back. 26. A cart according to claim 25 in which said end panels present front and back vertical guides extending downwardly from the forward and back ends of said passageway. 27. A cart according to claim 25 in which said outer and inner top panels present upper and lower door guides in said passageway. 28. A cart according to claim 27 in which some of said upper door guides do not overlie any said lower door guides. 29. A cart according to claim 26 in which a back panel extends between said top and bottom panel assemblies forwardly of said back vertical guides. 30. A base assembly for a cart, comprising: a rigid rectangular carriage frame surrounding a generally rectangular open area and having corner mounts for the attachment of wheel units; a bottom panel having a central portion depending into said open area of the carriage frame and having an outer border portion directly overlying said border portion at an elevation higher than the bottom of said central portion; and a bumper unit having an outer face spaced outwardly of the periphery of said bottom panel, said bumper unit having inside flanges clamped between said carriage frame and said border portion of the bottom panel. 31. A base assembly according to claim 30 in which corner portions of said bumper unit are backed by corner inserts. 32. A cart comprising: a generally rectangular bottom panel assembly having bottom wheel mounts adjacent its corners; a generally rectangular top panel assembly spaced above said base panel assembly; two vertical end panels each having front and back integral corner columns extending between said top and bottom panel assemblies; and four draw rods extending vertically through respec¬ tive of said corner columns, said draw rods being threaded into said top panel assembly and having enlarged heads engag¬ ing the underside of said bottom panel assembly for clamping said top and bottom assemblies against the upper and lower ends of said corner columns. 33. A cart according to claim 32 in which spacer tubes surround said rods through most of the length of the rods, said spacer tubes being arranged to be subjected to compressive forces when said rods are tightened beyond a pre¬ determined amount. 34. A cart according to claim 32 in which resilient members are provided which are arranged to be compressed responsive to tightening of said draw rods. 35. A storage unit comprising: a rigid bottom base frame; a molded plastic top panel having nut inserts molded therein; end panels between said base frame and top panel; and draw rods extending vertically through said end panels, each of said rods having an upper threaded end portion screwed into a respective one of said nut inserts and having an enlarged head at its lower end engaging the underside of said base frame. 36. A storage unit according to claim 35 in which spacer tubes are provided which surround said rods between said nut inserts and the upper side of said base frame. 37. A storage unit according to claim 35 in which a molded plastic bottom panel rests on said base frame. 38. A storage unit according to claim 35 in which a bottom panel is clamped by said draw rods between said base frame and the lower ends of said end panels. 39. A storage unit according to claim 38 in which an inner top panel is clamped by said draw rods between said base frame and the upper ends of said end panels, and said top panels provide a passageway therebetween for a tambour door. 40. A storage unit according to claim 38 in which wheels are mounted on said base frame and a bottom bumper frame is provided which is clamped by said draw rods between said base frame and said bottom panel. 41. A storage unit according to claim 40 in which a top bumper frame is clamped by said draw rods beneath said top panel. 42. A storage unit according to claim 39 in which a top bumper frame is positioned between said top panels. 43. A storage unit according to claim 35 in which top and bottom resilient bumper frames are located between said top panel and the upper end of said end panels, and between said base frame and the lower ends of said end panels, and are arranged to be clamped by tightening of said draw rods. 44. A cart according to claim 1 in which said cart includes a shelf extending between said end panels, and a swing-out bin resting on said bottom panel assembly and having a curved top arranged to engage the underside of said shelf when said bin is swung to an open position from a closed position. 45. A cart according to claim 44 in which a slide- out container rests on said shelf. 46. A cart according to claim 44 in which a bin stop extends across the bottom panel assembly in front of said bin, said bin being adapted to be removed from said cart by being lifted over said stop when the bin is in closed position.

Inventors: PROPST ROBERT L, PROPST, ROBERT, L.
Applicants: PROPST ROBERT L, PROPST, ROBERT, L.
Application year: 1990
Main classification: A47B31
IPC codes: A47B31