Display shelf device having a rigid structure

Claim 1

A display shelf device comprising: a pair of opposing side walls having inner upright surfaces facing each other, said upright surfaces being formed with a pair of substantially horizontal grooves respectively, each of said grooves having a first section adjacent to a respective one of said upright surfaces and a second section remote from said respective upright surface, said each groove having a vertical size greater at said second section than at said first section; and a shelf provided at opposite side edges thereof with mounting means for engagement with said side walls, said mounting means being received in said grooves such that said side walls are interconnected by said shelf, said mounting means comprising locking means received in said second sections of said grooves to lock said mounting means in said grooves, said locking means having a vertical size greater than said vertical size of said each groove at said first section whereby said side walls are secured together, wherein each of said side walls has front and rear ends defining therebetween said respective upright surface, said each groove comprising a main length including said first and second sections, said main length of said each groove extending rearward from said front end of a respective one of said side walls to an intermediate position between said front and rear ends of said respective side wall, and wherein said each groove further comprises an auxiliary length collinear and continuous with said main length of said each groove, said auxiliary length of said each groove extending rearward from said intermediate position, said each groove having at said auxiliary length a substantially constant vertical size generally equal to a vertical size of said first section at said main length.