Abstract:
A shelf comprising a base part ( 2 ) and at least one side ( 3 ) rigid with said base part, in which to enable the side ( 3 ) to be varied in position relative to the base part ( 2 ) and to maintain the position assumed, the side ( 3 ) and base part ( 2 ) are joined together by at least two deformable elements.

Description:
FIELD OF THE INVENTION 
     This invention relates to a collapsible-sided shelf, in particular of metal or non-metal wires, rods and rod-like elements, particularly for trolleys and fixed support devices. 
     BACKGROUND OF THE INVENTION 
     Shelves of plastic-coated metal wire, rods or rod-like elements are known, to be hooked at different heights to side walls provided or not provided with wheels, to form a trolley or a support device in which these (removable) shelves form a consolidating part of the trolley or device. These shelves comprise a substantially rectangular flat base part plus sides. The sides may form an integral part of the base part, in which case they are rigidly set substantially at 90° to the base part which, with the sides, assumes either a U-configuration, or a tray configuration if bounded by four sides. The overall size of such a shelf is considerable, and negatively affects transport and storage costs. 
     To reduce the overall size of such shelves it has already been proposed to provide them with collapsible sides which can be rotated from a substantially flat position lying on the base part to a position rotated through 90° therefrom. For this purpose the sides are provided with a number of rods, wires and rod-like elements shaped approximately as a half-closed hook which by engaging a surrounding rod of the base part enables the sides to be rotated away from and towards this base part. 
     Although this solution solves the size problem, it has certain drawbacks: the shelf is unstable and therefore also makes the trolley structure unstable; the shelf is uncomfortable to install between the side walls; and fitting the sides to the base part involves relatively complicated manual operations which cannot be automated. 
     An object of this invention is to provide a shelf provided with at least one side which forms one piece with the base part and can be made to manually assume a plurality of stable angular positions relative to said base part. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     A further object of the invention is to provide a trolley or a fixed support structure in which the shelf of the invention is applied. 
     These and further objects which will be apparent from the ensuing detailed description are attained by a shelf and a trolley or support structure in accordance with the teachings of the accompanying claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be more apparent from the detailed description of some preferred embodiments thereof given hereinafter by way of non-limiting example with reference to the accompanying drawings, on which: 
     FIG. 1 is a perspective view of a shelf of the invention provided with two sides shown in their erect position; 
     FIG. 2 is a perspective view of the shelf of the invention with its sides collapsed onto the base part; 
     FIG. 3 is a partial section through the shelf taken on the line  3 — 3  of FIG. 1; 
     FIG. 4 is a perspective view of a trolley or non-wheeled structure in which a shelf of the invention is mounted; 
     FIGS. 5 a, b, c, d, e  show schematically the different possible positions which the sides can assume relative to the base part; 
     FIGS. 6 a,    6   b  are two front perspective views of a further variant of a shelf according to the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the figures the reference numeral  1  indicates the shelf of the invention overall. It comprises a base part  2  and two sides  3  forming o n e piece with said base part. Both the base part  2  and the sides  3  are formed from metal or non-metal wires, rods or rod-like elements assembled together and surface-treated. 
     In particular, in the illustrated example, the base part  2  comprises three parallel longitudinal rod-like elements  4   a, b, c  (two side or outer elements  4   a, b,  bent at 90° at their outer ends at  4   d,  and one intermediate element  4   b ) and a series of parallel transverse rod-like elements  5  rigid with the three longitudinal rod-like elements  4   a, b, c.  The transverse elements  5  and longitudinal elements  4   a, b, c  involve only the base part  2 . 
     Spaced between the transverse elements  5  and fixed to the longitudinal elements  4   a, b, c  of the base part  2 , there are provided metal and non-metal elements of strap form, indicated by  6 , which are parallel to each other and, in that portion fixed to the base part  2 , also parallel to the transverse elements  5 . 
     According to the invention these straps are prolonged beyond the base part  2  to extend into the sides  3  and form a part of the structure of these latter. 
     More specifically, those portions of said straps which extend beyond the base part  2  are fixed, after a certain suitable free spacing distance indicated by  7 , to two (rod-like) parallel stringers  8   a, b  bounding the sides  3 , these latter being completed by a series of parallel rod-like elements  9  also fixed to the stringers  8   a, b.  Advantageously, the outer stringers  8   b  project outwards at their ends (at  10 ). 
     The base part  2  and sides  3  hence form one piece which can be produced entirely automatically without manual intervention. 
     The material of the straps  6  is chosen such that the sides  3  can be made to assume any position relative to the base part  2  by being bent (in the opening or closure direction) manually and without particular force along their free portion  7 , their assumed position persisting after the manual intervention ceases. The material is also chosen such that even after the position of the sides has been changed a certain number of times, the straps do not fracture within those free portions  7  in which the repeated bending occurs. Typical materials suitable both for bonding and for changing the position of the sides and their stability in the desired position are metals in general or other materials. 
     For example, steel wire covered with a thermosetting or thermoplastic plastic can be used. 
     The shape of the straps is such as to offer a low resistant moment to change in position of the sides (ie in the direction of side rotation relative to the base part) but to offer considerable resistance to any force exerted transversely to the straps in the direction of the arrows F of FIG. 1, so stabilizing not only the structure of the shelf but also, in consequence, the structure of the trolley or non-wheeled support structure to which the shelf is hooked or connected. 
     In the case of a trolley or non-wheeled element comprising conventional side walls of inverted U-shape provided at different heights with groups of parallel crosspieces  12  joining together the legs of the U and rigid with them, as seen in FIG. 4, the shelf  1  of the invention is mounted (either with the sides  3  collapsed onto the base part or with the sides  3  raised) on said crosspieces  12  such that the bent appendices  4   d  of the base part lie on the outside of the crosspieces and the base part of the shelf rests on these latter. If collapsed, the sides are then rotated to assume a position at approximately 90° to the base part, whereas the projecting parts  10  of the outer stringers  8   a  of the sides engage the legs of the U to prevent any outward rotation of the sides should an accidental thrust be applied to them. 
     The scope of the invention includes different embodiments of the shelf and sides in terms of the number and arrangement of their constituent rods, wires or the like. Instead of having a mesh configuration, the shelf and its sides could be formed with solid flat elements connected together by straps or similar elements. The same applies to the number of straps  6  used, which could be reduced to two. The straps  6  could also be limited in length to just the portion  7  plus short extensions to enable it to be fixed to the sides  3  and to the base part  2 . 
     As can be seen from FIGS. 5 a, b, c, d, e,  the-proposed embodiment of the invention enables the sides  3  to be positioned in various spatial arrangements. 
     The number of sides could also be limited to one or be such as to totally surround the base part  2  (FIGS. 5 d  and  5   e ). 
     FIGS. 6 a,    6   b  show a variant of the aforedescribed embodiments (those shelf parts in common with the aforedescribed embodiments are indicated by the same reference numerals thereas). 
     The shelf  13  of this variant is substantially identical to the lastly described embodiment and also comprises a base part  2  and sides  14  forming one piece with the base part, to which they are connected such as to enable their position to be modified as already described. 
     However, the sides  14  also comprise hooking elements  15 , preferably provided on the ends of said sides. 
     The hooking elements  15  have a vertical part  15 A and a hook-bent end part  15 B. The hooking elements are preferably formed by prolonging the outside bars  16 A,  16 B defining the ends of the sides  14 . 
     The length L of the hooking elements  15  is such that when the relative side  14  has been folded onto the base part  2  (FIG.  6 B), said hooking elements  15  lie completely within the base part. 
     The hooking elements  15  are arranged to hook onto an overlying shelf by engaging a horizontal rod-like element  16  of a side  14  in the free space between the vertical end bars  16 A,  16 B of the side and the immediately adjacent vertical bars  16 C, D. 
     To connect the shelves of this variant to a crosspiece  17 , for example provided inside a cupboard or connected to a support structure  18  (partially shown in FIG. 6 a ), preferably also rod-like, hanging means  19  comprising bent ends  20  able to cooperate with the bent ends  15 B of the hooking elements  15 , and a central  21  part bent to straddle the crosspiece  17 .