Pull-out tray for refrigerator shelf
United States Patent 1 1 1111 3,877,767  
 Bright 1 Apr. 15, 1975 [54] PULL-OUT TRAY FOR REFRIGERATOR 2,724,630 11/1955 Saunders 312/340 SHELF Primary ExaminerRoy D. Frazier [75] lnvemor&#39; James Bnght&#39; Dayton Ohm Assistant E.\&#39;an1inerR0bert A. Hafer [73] Assignee: General Motors Corporation, Attorney, Agent, or FirmEdward P. Barthel Detroit, Mich.  
 [22] Filed: Mar. 11, 1974 [57] ABSTRACT [2 1] A 1 M 449,326 A pull-out tray attachment for a refrigerator wire shelf wherein a tray is rotatably mounted on a pair of transverse rollers journalled in spaced relation by a center [52] 312/337; 312/340; 108/137; longitudinal spacer guide member which rollers are in V 211/126 turn in rolling contact with the wire shelf. The spacer 1211 Fiiiflra ariiiiji1:11.537171329 05311512? guide has for ramming and ing a rib of the tray which the guide is in turn retained and tracked on a supporting wire of the shelf by lower groove means in the guide. As the rollers engage both the tray and the wire shelf the rollers and center guide PULL-OUT TRAY FOR REFRIGERATOR SHELF This invention relates to a pull-out rolling tray add-on attachment for a conventional wire shelf used on refrigerators and the like.  
  It is an object of the present invention to provide a rolling tray attachment which may be removably supported in rolling fashion on a shelf of an appliance such as a refrigerator by means of transverse roller members journalled at each end of longitudinal spacer guide means whereby the tray may be withdrawn from the shelf about twice the distance traversed by the rollers to afford easy access to articles on the tray.  
  It is another object of the invention to provide a pullout tray assembly for a refrigerator wire shelf whereas the tray is rotatably mounted on a pair of transverse rollers journalled in spaced relation by a center longitudinally disposed spacer guide, which rollers are in turn in rolling contact with the wire shelf. and the spacer guide being provided with upper aligned grooves at each end for straddling and tracking a longitudinal underlying rib of the tray while the guide straddles and tracks on a supporting wire of the shelf by lower aligned grooves at each end of the guide, whereby the rollers and guide provide approximately a two to one rolling ratio allowing the tray to be extended from the shelf about twice the distance traversed by the rollers.  
  Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred embodiment of the present invention is clearly shown.  
  FIG. 1 is a plan section with parts broken away of a refrigerator cabinet showing a preferred embodiment of the invention;  
  FIG. 2 is a sectional elevation taken on line 22 of FIG. 1 with the tray extended position shown in phantom;  
  FIG. 3 is a sectional elevation taken on line 3-3 of FIG. 1;  
  FIG. 4 is an enlarged fragmentary view, partly in section, taken on line 44 of FIG. 1; and  
  FIG. 5 is an enlarged perspective view of the shelf center guide.  
  Referring now to the drawings and more particularly to FIG. 1, a partial view of a refrigerator cabinet is shown having the conventional side walls 12 and rear wall 13 with inner cabinet liner 14 defining a refrigerator compartment 16. A rolling tray attachment structure embodying the invention is indicated generally at and is arranged for ready removal from the refrigerator compartment wire shelf 28. The shelf 28 is of the cantilever type and includes a front crossbar 30&#39;and a rear crossbar 32 which, like the front crossbar 30, is of heavy wire. The shelf 28 also includes a central crossbar 34 of heavy wire parallel to the front and rear crossbars 30 and 32. A pair of cantilever arms 36 and 37 in the form of wedge-shaped thin plates are fastened to the opposite ends of the Crossbars 30, 32 and 34 and form the sides of the wire shelf 28. As seen in FIG. 2, the cantilever arms are mirror images and each is provided with an upper rear hook 38 and a lower rear hook 40 which extend and hook into adjacent notches or slots 41 in adjacent vertical stringers or rails 42 and 43 extending up the back wall of the compartment 16 near the corners thereof. The wire shelf 28 also includes a series of uniformly spaced wire supports 44 parallel to the arms 36 and 37 resting upon and bonded to the cross bars 30, 32 and 34 to form the main supporting surface of the shelf 28.  
  Spaced above the wire shelf 28 is the tray portion 50 of the tray attachment assembly 20 which tray is preferably made from suitable plastic material such as modifled acrylic or clear hi-impact ABS plastic, for example. The tray base 52 extends horizontally between a pair of parallel longitudinal side rails 54 and 56, while the rails extend vertically both above and below the base 52. As seen in FIG. 3, lower flange portions 58 and 59 of the side rails are positioned to engage the outer end faces of end caps or discs 61 and 62 located at each end of a pair of transversely extending longitudinally spaced parallel rollers 63 and 64, preferably formed of plastic material such as Nylon rods, which are rotatably received in front and rear transverse bores 65 and 66 respectively, located at the ends of longitudinally extending spacer guide means 67 (FIG. 5).  
  With reference to FIG. 5, the preferred form of the spacer guide means is an integral one piece center spacer guide 67, preferably molded from plastic material such as high impact polystyrene, formed H-shaped in transverse section. including a horizontal gusset plate 68 and a pair of vertical stiffener flanges 69 and 70. Integrally molded on each end of the spacer guide are front and rear hub members in the form of a pair of cylindrical bosses-7l and 72 each having transverse bores 65, 66 respectively. therethrough for the reception of their associated frontand rear rollers 63 and 64. Each of the hub members 71 and 72 preferably comprise front 73, 74 and rear 75, 76 pairs of transversely spaced hub portions, respectively providing a left front and rear set 73, and a right front and rear set of Iongitudinally aligned hub portions. Each of the hub members 71 and 72 are formed with upper 80 and lower 82 longitudinally aligned grooves extending transverse to their associated bores 65, 66, with the grooves of a predetermined depth intercepting the bores to expose the upper and lower intermediate surface of the rollers 63 and 64 when the rollers are positioned in their respective bores 65 and 66. In this manner the center spacer guide 67 is readily located on the wire shelf 28 by aligning the bottom grooves 82 on a longitudinal wire support 44 as shown in FIG. 4.  
  As best seen in FIGS. 3 and 4, the grooves 80 and 82 have a defined vertical depth which intersects the upper and lower portions of each of the bores 65 and 66, respectively, such that with the front roller 63 inserted through the bore 65 the lower intermediate portion of the roller 63 is exposed for rolling contact with a central wire support 44&#39; while the remaining portions of the roller 63 rollingly contacts underlying wires 44. The tray base 52 is formed with a plurality of longitudinally extending transversely spaced ribs 84 preferably integrally molded on the undersurface thereof and disposed in vertical alignment with the equally spaced shelf support wires 44. Thus the rib 84&#39;, which lies on the longitudinal center line of the tray 50, is received in the aligned front and rear upper grooves 80 so as to rollingly contact the exposed upper intermediate surface of the front and rear rollers 63 and 64 while the remaining tray ribs 84 are supported in rolling fashion on the rollers when the tray is located as shown in FIG. 3.  
  FIG. 3 also depicts how each of the end discs on each roller, such as end disc 61, for example, is aligned outboard of the outermost support wire 44&#34; and the outermost rib 84&#34; on the right side of the tray and inboard of the lower lip flange 58 to retain the rollers from transverse movement relative to the shelf 28, and allow the discs to track relative to the. wire shelf while the shelf tracks relative to the rollers and center guide 67.  
  At the rearward edge of the tray base 52 there is provided a transverse rear wall 90 the lower edge of which has integrally molded thereon a plurality of transversely extending wire retaining guide means preferably in the form of equally spaced L-shaped hook members&#39;9l defining slots 92 of the bayonette type so that the ends of the slots are first placed over the wires 44 i and then the shelf is laterally shifted slightly to move the wires into the inner ends of the slots 92.&#39;Thus, the wire supports 44 are engaged by the slots 92 and the tray 50 cannot be vertically raised from the wire shelf while the tray is able to freely roll in longitudinal fashion on the roller members, which roller members in turn freely roll on the support wires 44. Because applicants rollers roll on the wire supports there is provided a 2 to 1 diameter to radius ratio of the tray versus the rollers which allows the tray 50to extend about twice the distance outwardly fromthe forward edge of the wire shelf at its maximum extended position, shown in phantom in FIG. 2, while the roller members 63 and 64 and spacer guide means 67 have moved forward to the front edge of the wire shelf.  
  It will be noted that the front hub member of the guide means 67 engages the shelf front edge strip 94 to limit the forward travel thereof as seen in phantom in FIG. 2, while the rear wall guide means or hooks 91 engage the rear hub member 72 to limit the forward travel of the tray 50. In the disclosed embodiment the tray 50 travels forward to a maximum extended distance indicated by the dimension A in FIG. 2 of about eight inches while the rollers 63, 64 and spacer guide 67 roll forward a maximum extended distance, indicated by the dimension one-half A, of the order of about four inches. In the preferred form the spacer guide 67 is of a predetermined length to position the rollers 63 and 64 on about 7.3 inch centers, which dimension is dictated by the position of the transverse intermediate cross-bar or wire 34 relative to rear wire 32. That is, the disclosed spacer guide 67 has a maximum longitudinal dimension of about, 7.8 inches which insures that the front hub member 71 will contact the rear face of shelf front edge strip 94 just before the rear wall hooks 91 contact the wire 34. it will be appreciated, also, that the rollers 63, 64 are of a diameter, which in the disclosed form is about 0.3 inches, sufficient to allow the tray ribs 84 to clear the upper surface of the shelf front edge strip 94.  
  While the embodiment of the present invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted.  
 1 claim:  
  I. A removable roll-out tray assembly for a cabinet shelf which has spaced longitudinal wires, said tray assembly comprising, spacer guide means mounted on the shelf, said spacer guide means including front and rear pairs of transversely spaced longitudinally aligned hub portions, one set of front and rear aligned hub portions being located between a first pair of shelf wires and the other front and rear set of aligned hub portions being located between a second pair of wires, means for retaining each said pair of hub portions in fixed longitudinally spaced relation, a front transversely extending roller rotatably mounted in said front pair of hub portions, a rear transversely extending roller rotatably mounted in said rear pair of hub portions, each said front and rear roller in rolling contact on the. wire shelf, means for retaining said front and rear pair of hub portions in fixed transverse spaced relation, a tray member having a plurality of longitudinally extending transversely spaced rib members on the undersurface thereof, said rib members having a predetermined depth such that said tray is rollingly supported invertical spaced relation above said hub portions on said rollers, said tray assembly being operative to be rolled out.-  
 wardly from the shelf forward edge to an extended position by means of said tray rib members rolling on said front and rear rollers while said rollers in turn roll on the longitudinal shelf wires whereby said tray member travels through a distance approximately twice the distance traveled by said rollers together with said spacer guide means.  
  2. A removable roll-out tray assembly for a domestic refrigerator shelf which has spaced longitudinal wires, said tray assembly comprising: a unitary spacer guide having front and rear longitudinally aligned hub members, each said hub member having a bore rotatably receiving a transversely extending roller; each of said front and rear hub members being provided with upper and lower vertically aligned longitudinally extending slots; said lower pair of front and rear slots being aligned for receiving a common longitudinal shelf wire therein, said lower. pair of slots being of a predetermined depth allowing their associated front and rear rollers to rollingly contact the common shelf wire, a tray member having a plurality of longitudinally extending transversely spaced ribs on the undersurface thereof, the upper pair of front and rear slots of said hub members being aligned and receiving a central tray rib therein with said upper pair of slots beingof a pre determined depth to allow said central tray rib to rollingly engage said front and rear rollers, said remaining tray ribs being rollingly supported on the outboard portions of said front and rear rollers; said tray assembly being operative tobe rolled outwardly from the front edge of the shelf to an extended position by means of said tray ribs rolling on said front and rear rollers while said front and rear rollers in turn roll on the shelf longitudinal wires resulting in said tray traveling through a distance approximately twice the distance traveled by said spacer guide and said front and rear rollers, and  
 means on the underside of said tray for slidingly engag: ing a plurality of the remaining shelf wires to guide said tray, said engaging means positioned to engage said spacer guide and thereby limit the outermost travel thereof.  
 3. A removable roll-out tray assembly for a domestic refrigerator shelf which has spaced longitudinal wires, said tray assembly comprising: a unitary spacer guide having front and rear longitudinally aligned cylindrical hub members, each said hub member having a bore rotatably receiving a transversely extending roller, said front and rear rollers having a length substantially equal to the transverse dimensions of said trayand having discs affixed to each end thereof; each of said front and rear hub members being provided with upper and lower vertically aligned longitudinally extending, slots; said lower pair of front and rear slots being aligned and receiving a common longitudinal shelf wire therein, said lower pair of slots being of a predetermined depth allowing their associated front and rear rollers to rollingly contact the common shelf wire. a tray member having a plurality of longitudinally extending transversely spaced ribs on the undersurface thereof, the upper pair of front and rear slots of said hub members being aligned and receiving a central tray rib therein with said upper pair of slots being of a predetermined depth to allow said central tray rib to rollingly engage said front and rear rollers while providing a clearance between the underside of said tray and said front and rear hub members. said remaining tray ribs being rollingly supported on the outboard portions of said front and rear rollers; said tray having lower side flanges spaced from the outermost tray rib allowing said end discs to trace therebetween, said tray assembly being operative to be rolled outwardly from the front edge of the shelf to an extended position by means of said tray ribs rolling on said front and rear rollerswhile said front and rear rollers in turn roll on the shelf longitudinal wires resulting in said tray traveling through a distance approximately twice the distance traveled by said spacer guide and said front and rear rollers, and means on the underside of said tray for slidingly engaging a plurality of the remaining shelf wires to guide said tray, said engaging means positioned to engage said spacer guide and thereby limit the outermost travel thereof.  
  4. A removable roll-out tray assembly for a domestic refrigerator shelf which has spaced longitudinal wires, said tray assembly comprising: a unitary spacer guide having front and rear longitudinally aligned hub members, each said hub member having a bore rotatably receiving a transversely extending roller; engagement means on the ends of the front and rear hub members being provided with upper and lower vertically aligned longitudinally extending slots; said lower pair of front and rear slots being aligned and receiving a common longitudinal shelf wire therein, said lower pair of slots being of a predetermined depth allowing their associated front and rear rollers to rollingly contact the common shelf wire, a tray member having a plurality of longitudinally extending transversely spaced ribs on the undersurface thereof. said ribs being spaced so as to be in substantial vertical alignment with the longitudinal wires of the shelf the upper pair of front and rear slots of said hub members being aligned and receiving a central tray rib therein with said upper pair of slots being of a predetermined depth to allow said central tray rib to rollingly engage said front and rear rollers, said remaining tray ribs being rollingly supported on the outboard portions of said front and rear rollers; said roller end engaging means being positioned outboard ofthe tray outermost ribs and their associated underlying shelf wires to retain said rollers against transverse movement. said tray assembly being operative to be rolled outwardly from the front edge of the shelf to an extended position by means of said tray ribs rolling on said front and rear rollers while said front and rear rollers in turn roll on the shelf longitudinal wires resulting therein.