Stackable tray
I Umted States Patent 1191 1111 3,874,510 Perry et a]. Apr. 1, 1975 [5 STACKABLE TRAY 2.603.36! 7/1952 Jarnesy 211/126 1 1 Gordon Perry, Baysidfi Row 33233133; 1311335 l&#39;r ir&#39;lII...IIIIIIIIIIIIIIIIIIIIIIIII ii 1152 Schmidt, Freepofl, both of 3.552.519 1/1971 sim n et 1. 211/126 Assigneez O f Pendaflex C p 1675,8&#39;5 7/[972 Rehrlg 211/126 Garden City1 NX&#39; 3,79L528 2/l974 Brendgord 2| l/l26 [22] Filed: 1973 Primtzry Examiner-James T. McCall [21] Appl. No,; 411,638 Assistant Examiner-Darrell Marquette Attorney, Agent, or Firm-Darby &amp; Darby [52] U.S. Cl. 211/126, 211/[77 [5 1] Int. Cl. A47f 3/14 [57] ABSTRACT [58] Field of Search 2ll/l26, 177, ll; 206/503.  
  206/5] 1, 5n Th1s lnventlon relates generally to trays of the type used for holding paper, letters, or the hire, and more [56] References Cited particularly, to trays which are stackable upon each UNITED STATES PATENTS 3/1941 Hearn etal. 2ll/l26 other.  
 2 Claims, 5 Drawing Figures PATENTEDAPR 119?.5 3.874.510  
 sum 1 {If 2 PATENIEDAPR&#39; H975 3,874.51 0  
 smaarz FIG. 3  
 STACKABLF, TRAY In the usual configuration. trays of the above type have been stacked upon each other in order to provide plural compartments for diverse material. e.g.. various forms. stationary. etc. In the past. these stacked trays have been held together by tneans of one or more mating tongue and groove or peg and hole stacked contigurations. Thus. a plurality of trays may be stacked by mating each additional tray to either the top or bottom of an existing tray stack. This form of construction has the inherent disadvantage of requiring plural supporting points around the periphery ofeach tray. thus making impossible a cantilever configuration wherein adjacent trays contact each other only at the rear portion of each tray. Access to all but the uppermost stacked tray is thereby limited to entry only from the forward opening of each tray. In addition. lack of any fastening means between trays results in an unsecure structure. wherein trays may be inadvertently dislodged from their normal positions within a given stacked array.  
 SUMMARY OF THE INVFN&#39;IION Accordingly. an object of this invention is to provide a new and improved stackable tray assembly.  
  Another object of the invention is the provision of a new and improved stackablc tray assembly having increased rigidity.  
  Still another object is the provision of a new and improved stackable tray assembly of tmcomplicated design.  
  Brielly. in accordance with a preferred embodiment of the invention. these and other objects are attained by providing Each supporting at least one supporting bracket which is detachably fastened to the underside of an associated upper tray and downwardly extended to engage the upper side of a lower adjacent tray. Clamping means are provided to detachably secure adjacent trays by means of longitudinal compression upon the supporting bracket.  
 DESCRIPTION OF THE DRAWINGS The invention is described in detail below with reference to the accompanying drawings. wherein:  
  FIG. I is a perspective view of the underside of a stackable tray and of an associated supporting bracket in detached configuration;  
  FIG. 2 is a perspective view of a stacked tray assembly&#39;.  
  FIG. 3 is a side view in sectiorl of a portion ofthe two stacked trays shown in FIG. 2 illustrating the insertion of the spring clamp;  
  FIG. 4 is aside view in section similar to FIG. 3 subsequent to insertion of the spring clamp: and  
 FIG. 5 is a sectional view along line S5 in FIG. 4.  
 DESCRIPTION OF THE PREFERRED EMBODIMENT tray configurations may be used within the scope of the present invention.  
  Each tray has a pair of guides l8 integrally provided on the downwardly facing surface of bottom wall 6. In the present embodiment these guides are formed on respective ones of a pair of extruded ledges or shoulders I2 which extend front the rear edges of the tray tapering toward each other terminating in a shoulder 30. A planar wall I3 is integrally formed with and at right angles to shoulders I2 and provides a rearward boundary for any material placed on the respective tray.  
  A pair of generally L-shaped supporting brackets 10 (only one shown) have dovetail ways 22 fornted in their short legs which correspond in shape with the guides l8. A tab 24 is provided at the free end of the long leg of each bracket Ill. The long leg preferably has a L&#39;- shaped cross-section for strength and rigidity. As shown in FIG. I. the bracket I0 is fitted over guide I8 while the second supporting bracket (not shown) engages the remaining dovetailed guide in a like manner. The upwardly facing surface of each bottom wall 6 has a pair of slots 20 FIGS. 3 and 4) formed therein which receive the tabs 24 extending from the respective brackets III.  
  A pair of channels In are provided on the side edges of wall I3. Each channel has an opening 26 therethrough formed below the plane of rear wall I3 FIGS. 3 and 4). The lower edge ofeach channel has a depending portion 3] which interlocks with a recess 33 formed in the upper edge of the channel which is associated with the tray stacked immediately below. Upon stacking the trays upon brackets 10. the channels are aligned. An elongate spring clamp 14 having a generally C-shape has its ends inserted through openings 26 in the respective upper and lower channels. When in place. the spring clamp 14 holds trays Sand 5&#39; together by means of compression longitudinally applied to the supporting bracket It).  
  In the preferred embodiment of the invention. a pad 28 is provided on each ofthe shoulders 12 of each tray. A non-slip material (e.g.. felt or rubber) is used for this purpose. The bottom tray in a given stack will thus rest upon its two pads 28 and the forward shoulder 30.  
  There are many possible variations of the basic invention. The number of supporting brackets employed may vary depending upon the desired structural rigidity. Both the number and the configuration of the clamping means may vary. such number not necessarily being restricted to the number of supporting brackets. While the figures illustrate the use of spring clamps I4 inserted through openings in aligned channels which are located adjacent to each bracket 10. alternate clamping means may be employed. For example. a single spring clamp may be inserted through guide holes located midway along the back sides ofeach tray. However, it is advantageous to have the spring clamp substantially adjacent to the support brackets so that the compressive force exerted thereby is applied to the support brackets 10. thus providing optimal rigidity and stability to a stacked array of trays.  
 What is claimed is:  
 l. A stackablc tray assembly comprising:  
 at least two vertically adjacent trays designated an uppermost tray and a lowermost tray. each of said trays including a bottom wall; and  
 at least one generally L-shaped bracket. said hracket heing detachahly fastened solely to said adjacent trays;  
 at least one extruded shoulder extending downwardly from the underside of the bottom wall of each ol ol the bottom wall ol the lowermost tray having a recess to cooperate with said tab.  
  2. A stackahle tray assembly as recited in claim I. each of said trays including a rear wall having at least one opening therein. at least one elongate spring clamp having a generall C-shaped construction having two arms and a bridge portion, one arm of said clamp passing through said opening in the rear wall of the uppermost tra the other arm of said clamp passing through said opening in the rear wall ot the lowermost tray. whereby adjacent tra \s are compressed against said supporting bracket