referring initially to fig1 , and 6 , bracket assembly 10 comprises a frame 12 , formed of steel , aluminum or the like , having a rear wall 14 and two forwardly - extending parallel side walls 16 and 18 . each side wall is formed into upper and lower arms 20 , 22 , respectively , defining a pair of slots 24 therebetween dimensioned to accept the rear edge 26 and adjoining portion of shelf 28 . when so inserted , the shelf extends outwardly from the bracket assembly 10 in a cantilever manner . in order to retain the shelf in the bracket , locking means are provided . as detailed in fig2 , and 6 , mounted to the rear wall 14 is hook arm assembly 30 , comprising a pair of hook arms 32 each having a depending hook portion 34 at its distal end . the hook arms extend forwardly from a base plate 36 . the base plate 36 is mounted to the front surface of bracket rear wall 14 between the side walls 14 , 16 by a clamp 38 formed in the rear wall . a rearwardly - extending tab 40 on the base plate locks into a mating rectangular aperture 42 on the rear wall . the hook arms and hooks are positioned so as to engage with a depression or notch located on the top surface of the shelf to be inserted into the slots 24 formed by the bracket arms . as shown in fig1 the notch may be in the form of a longitudinally - extending slot 44 , positioned with respect to the shelf rear edge 46 to be engaged by the hooks when the shelf is fully inserted into the reception slots . the hooks each may be provided with an angular , forwardly - directed cam surface 48 to permit an upwardly - directed force to be generated at the point of contact with the shelf as the shelf is inserted . as the hook arms are formed from a resilient material such as an appropriate plastic composition , the hook arms flex slightly , permitting insertion of the shelf , followed by interlocking between the hooks and the shelf slot 44 . the locking mechanism formed between the bracket hooks and shelf slot insures that the shelf 24 cannot be inadvertently removed from the bracket . to allow shelf removal when desired , however , the bracket unit 10 includes a cam mechanism 50 . as may be seen , cam arm 52 is pivotally mounted between the hook arms 32 on axle 54 extending therebetween . the forward portion 56 of the cam arm serves as an actuating handle or arm , and when lifted as shown by the arrow in fig3 causes the rearward cam portion 42 to rotate downwardly into contact with the top surface of the inserted shelf 24 . because the axle is mounted to the hook arms , the upward force on the actuating cam arm portion 56 allows the hook arms to flex upwardly about the line of contact between the rearward portion of the cam arm and the shelf , lifting the hooks 34 out of engagement with the shelf slot 44 . while the hooks are maintained in the raised position , the shelf 24 may be pulled forward , out of engagement with the bracket . the shelf is thus removable for restocking , replacement or other desired activities . to allow the bracket to be mounted to a shelf support system , the bracket near wall 14 may be provided with appropriate mounting means . to provide increased flexibility of mounting , and to allow the bracket to be used with a variety of support system configurations , adaptor plates may be used between the bracket and support element . as presented in fig1 through 3 , a metal or other rigid material adaptor plate 60 may be used to allow mounting of the bracket assembly 10 to a shelf support structure having a plurality of horizontally - extending beams or bars , as exemplified by the element 62 . in order to engage the adaptor plate the bracket includes a pair of rearwardly and upwardly - projecting mounting pins 64 , extending from the upper edge of rear wall 14 . in addition , a pair of flexible lower mounting hooks 66 , are preferably formed as projections on an insert 68 which is mounted between the lower arms 22 on a projection 70 extending between the arms from rear wall 14 . ( see fig6 ). the insert embraces the projection and is maintained in position by a key ( not shown ) which engages the cutout 72 in the projection . the mounting hooks , which are provided with locking flanges 74 at their distal ends , project through apertures in the bracket rear wall 14 . by constructing the insert and hooks out of a plastic material , sufficient resiliency can be obtained to permit a snap action fit between the bracket assembly and adaptor plate to be achieved . as illustrated in fig1 the adaptor plate includes a front plate 76 against which the bracket assembly lies , apertures 78 , 78 and 80 , 80 being dimensioned and located to accept the mounting pins 64 and the mounting hooks 66 , respectively . it is to be appreciated that the bracket assembly is mounted to the adaptor prior to insertion of the shelf 24 , the pins 64 being inserted first , followed by a pivoting motion of the bracket assembly with respect to the adaptor to allow the hooks 66 to pass through the lower aperture 62 and lock the elements together . a pair of rearwardly - extending mounting ears 82 on the adaptor plate define a pair of vertical slots 84 , dimensioned as seen in fig2 and 3 , to allow the adaptor plate and thus the mounted bracket assembly 10 to be hung on the transverse bar 62 . such a construction permits the bracket assembly to be positioned as desired along a given bar . as shown in fig4 and 5 , a second form of adaptor 86 , formed of steel or the like , may be utilized to allow mounting of the bracket assembly 10 on a shelf standard structure having spaced , transverse rungs as depicted by the rungs 88 , 90 . as depicted in those figures , the adaptor 86 again includes plate 76 against which the bracket assembly rests , with the apertures 80 for acceptance of the bracket mounting pins 64 . as the mounting rungs typically have limited clearance between their rearwardly - facing surfaces and a shelf system partition or wall 92 , the plate 76 is displaced forwardly from the inverted u - shaped mounting flange portion 94 of the adaptor by an intermediate portion 96 . formed ledge portion 98 , adapted to engage and rest upon a second rung 90 , is similarly displaced rearwardly from the mounting surface 50 by a second lower intermediate section 100 , which is provided with the second apertures 82 for the hooks 66 . typically , multiple brackets 10 used to support a shelf after positioning the brackets as required on the shelf support system , either alone or in conjunction with an adaptor , the shelf may be inserted into the brackets and is locked in place . when removal of the shelf is required , the cam is manually operated to disengage the locking assembly , allowing the shelf to be removed by a horizontal withdrawing action . adjacent shelves need not be disturbed by either insertion or removal . it is to be recognized by those skilled in the art that variation and modification of the invention as set forth herein may be accomplished without departing from the true scope of the invention .
a cooperating shelf and bracket system having a bracket which embraces and engages the rear portion of the shelf so as to support the shelf and permit its mounting in cantilever fashion from a shelf upright . the bracket may be formed with arms which grip cooperating structure on the shelf so that when fully inserted the shelf is securely retained in the bracket . the shelf is easily removable via a releasing system , which permits the shelf to be inserted and removed in a horizontal plane without the need for rotation relative to the bracket .