Patent Publication Number: US-6216892-B1

Title: Shelf unit

Description:
The present invention relates to a shelf unit comprising uprights and shelves suitable for being connected to said uprights to form shelving. 
     BACKGROUND OF THE INVENTION 
     Units of that type are known, in which the shelves are fixed to the uprights in various manners. Units exist in which the shelves are not adjustable, in which case battens or the like or used as fixing systems for fixing the shelves. Units also exist in which the uprights are in a plurality of portions, each of which is equipped with end-pieces that co-operate with bores provided at all four corners of the shelves. 
     Units also exist in which the shelves are adjustable, and in which the shelves rest on rests which can be displaced vertically along racks provided on the uprights. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a shelf unit that uses a different system for mounting the shelves on the uprights, which system is extremely simple. 
     This object is achieved by the fact that the uprights are formed by two flanks each provided with a plurality of windows into which the ends of the shelves are suitable for being inserted, such that, at each end of a shelf, clearance is provided between a horizontal “locking” face of the shelf and a “locking” edge of the window, which edge faces the locking face, and by the fact that, for each shelf, said unit is provided with at least two locking elements, one for each end of the shelf, each locking element comprising a clamping member suitable for being inserted between the locking face of the shelf and the locking edge of the window, and for being displaced so as to come into contact with said locking face for locking the shelf. 
     The uprights are shaped rather like ladders whose horizontal bars or “rungs” serve to hold the shelves of the shelving. For this purpose, the ends of the shelves are inserted into windows provided between two successive bars, and they are wedged in this position by locking elements. The bars provided between the windows form successive levels on which to position the shelves. Thus, depending on the vertical spacing between two successive windows, it is possible to dispose a shelf in each of the windows, or else to dispose shelves in only some of the windows, so as to select the spacings between the shelves. 
     Advantageously, each window has a horizontal bottom edge forming a bottom bearing surface for the end of a shelf, the locking edge being the top edge of the window. 
     Thus, the bottom surface of each shelf rests on the bottom edge of a window, which edge also forms the top edge of a bar. When manufacturing the uprights, it is easy to dimension the bottom edges of the windows such that they form bearing surfaces of area sufficient to support the shelves with a given load. 
     In an advantageous configuration, the unit includes means for fixing the locking elements to the flanks forming the uprights while enabling the locking elements to be moved relative to the locking edges of the windows. 
     This makes it easier both to assemble and to disassemble the shelf unit. Once the locking elements have been fixed to the uprights, the various component parts of the shelf unit can be handled without any danger of losing a locking element. The uprights can be delivered with the locking elements already in place for each window. It is also possible to make provision for the unit to be delivered with a given number of locking elements that corresponds to the number of shelves to be installed, and for the user to fix the locking elements to the uprights prior to installing the shelves. 
     Advantageously, the clamping members are in the form of clamping wedges. 
     The clamping wedges may be inserted between the shelves and the facing locking edges, and locking is obtained merely by displacing the clamping wedges while taking account of the direction in which they slope. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be better understood, and its advantages will appear more clearly on reading the following detailed description of embodiments shown by way of non-limiting example. The description makes reference to the accompanying drawings, in which: 
     FIG. 1 is a perspective view showing a shelf unit of the invention; 
     FIG. 2 is a fragmentary view looking along arrow II of FIG. 1; 
     FIG. 3 is a horizontal section view on line III—III of FIG. 2; 
     FIG. 4 is a vertical section view on line IV—IV of FIG. 2; 
     FIG. 5 is a perspective view showing a locking element; 
     FIG. 6 is a fragmentary perspective view showing another embodiment; 
     FIG. 7 shows a locking element as in the embodiment shown in FIG. 6; 
     FIG. 8 is a view analogous to the FIG. 6 view, showing yet another embodiment; and 
     FIG. 9 shows an assembly element suitable for being fitted to the uprights of the unit of the invention. 
    
    
     MORE DETAILED DESCRIPTION 
     FIG. 1 shows the two uprights  10  and  12  of a shelf unit, the shelves  14  of which are merely outlined in dashed lines. The uprights  10  and  12  are formed by two identical flanks. Each of them is provided with a plurality of windows  16  which are disposed one above another and which all have the same dimensions. The length L of a window, as measured in the depth direction of the unit, is at least equal to the width l of each of the shelves (it can be slightly greater). In the height direction, each of the windows has a height that is slightly greater than the thickness E of a shelf. Thus, as can be seen for the bottom windows and for the top windows of the uprights, the ends  15 A of the shelves can be inserted into said windows, over the entire width of said ends. 
     The uprights  10  and  12  can thus be likened to ladders, the wall elements  18  situated between two consecutive windows  16  forming the rungs of the ladders, said windows being delimitated on each side thereof by respective posts analogous to upright bars of a ladder. 
     FIG. 2 shows more clearly the shape of the window  16  with which the bottom end  10 A of the upright  10  is provided. It also shows the bottom region of the wall element  18  situated immediately above said window. 
     The end of a shelf  14  is inserted into the window  16 . It can be seen that the bottom face  14 A of the shelf rests on the horizontal bottom edge  16 A of the window, which edge thus forms a bottom bearing surface for the shelf. The locking face of the shelf is its top face  14 B, and it can be seen that clearance is provided between said top face  14 B and that edge  16 B of the window  16  which faces it. This locking edge  16 B is the top edge of the window  16 . 
     In the example shown, the clearance between the face  14 B and the edge  16 B is of height that varies between a maximum height j 1 , in a middle region of the window and a minimum height j 2 , at the front and rear ends of the window. 
     The edge  16 B is thus V-shaped, with the tip of the V pointing upwards, and its two branches forming two ramps  17 A and  17 B that slope relative to the horizontal. 
     The unit is provided with two locking elements  20  and  22  at each of the ends of each shelf, i.e. with four locking elements per shelf. 
     In general, it is necessary to provide at least one locking element for each end of each shelf. As shown in FIG. 2, each locking element  20  or  22  includes a portion that is inserted between the locking face  14 B of the shelf and the locking edge  16 B of the window. The arrows F indicate that the locking elements may be displaced by sliding them along the ramps  17 A and  17 B so as to lock the shelf. 
     The portions of the elements  20  and  22  that are inserted between the shelf and the locking edge are designated respectively in FIG. 2 by the references  21  and  23 . It can be seen that they slope so that they form wedges. It is thus easy to see that the shape of the elements  21  and  22 , combined with the decreasing clearance between the locking edge  16 B and the top face  14 B of the shelf, enable the shelf to be locked in the window  16  once the locking elements  20  and  22  have been slid to the ends of their strokes. 
     In the variant shown in FIGS. 1 to  5 , the locking elements are constituted by sliders for which the locking edges  16 B form rails. 
     In vertical section, the wall elements  18  are I-shaped in overall shape. Each of them thus has a central web  18 A which forms the vertical bar of the I, and two cross bars  18 A and  18 C which form the top and bottom bars of the I. 
     Via its top face, the top cross bar  18 B defines the bottom edge of a first window, while the bottom cross bar  13 C defines the top edge of another window situated under the first window, and of which it forms the locking edge. 
     The locking elements  20  and  22  are provided with side flanges  24  and  25  whose free ends  24 A and  25 A extend inwards to form lips overlying the top faces of the wedges  21 . 
     Thus, the locking elements are disposed such that the bottom bar  18 C is engaged under the lips  24 A and  25 , thereby enabling them to slide. 
     In FIGS. 1 to  3 , it can be seen that that portion of each of the bottom bars  18 C which is in the middle relative to the depth direction of the unit has notches so that, in order to install a locking element  20 , it is necessary merely to dispose it under the bar  18 C by placing the lips  24 A and  25 B in register with the notches  18 D, and then to push it upwards prior to moving it in the direction indicated by the arrows F. 
     In this situation, the bottom bar is held captive between the lips. The notches  18 D thus facilitate installation of the locking elements, which is particularly advantageous if the unit is delivered with only that number of locking elements which corresponds to the number of shelves, and if, to assemble the unit, the user must dispose the locking elements on the locking edges of those windows into which the user wishes to insert the shelves. 
     It is also possible to consider other ways of installing the locking elements, e.g. by clipping or the like. In any event, it can be understood that once the locking elements have been installed so that the bottom bars  18 C are engaged under the lips, it is possible to handle the component parts of the unit without any danger of the locking elements being lost. 
     It can be seen in FIG. 3 that the bottom bar  18 C flares at its ends  18 ′C, which determines the extreme advancement positions of the locking elements  20  and  22 , beyond which positions they cannot advance towards said ends. 
     The various component parts of the shelf unit may be made of a plastics material. In order to limit the manufacturing costs and the weight of the unit, the thicknesses of the parts are as small as possible, and it can thus be seen in FIG. 3 that the posts  11 A and  11 B that form the side ends of the flanks are hollow. For example, each of the flanks may be molded in one piece. Advantageously, the posts  11 A and  11 B are hollow through from end to end, thereby facilitating the manufacture of the uprights of the unit. 
     FIG. 9 shows an end-piece  50  that may be disposed at the top end of each of the posts. The end-piece is in the form of a substantially tubular element, one end  52  of which is closed. 
     The end-piece may be fitted to the top end of a post  11 A or  11 B. In the example shown, the end-piece may be engaged in said top end while being held in place by abutment by means of a bead  53  provided on its axial wall  51 . 
     The end-piece  50  may serve to finish a post by means of its closed end wall  52 . It may also serve to assemble together two posts disposed one above the other. The bottom end of the top upright then overlies the end-piece while being retained by the bead  53 . 
     It is thus possible to use the unit as a modular element assembled together with elements of the same type on either side and above and below it. 
     The shelves are also advantageously made of plastic; they may be molded or blown. However, they are advantageously made in long lengths, by extrusion, and then cut to the desired length. In which case, finishing trim may be installed on the edges of the shelves. 
     It should be noted that it is quite possible to dispose intermediate uprights in middle regions of long shelves, e.g. in the region A indicated in FIG.  1 . The locking elements are easy to manipulate in order to adjust the positions of the intermediate uprights and the spacing between them and the other uprights, as a function of the load on the shelves. 
     In general, in the first embodiment, the locking edge  16 B of each window has at least one ramp sloping relative to the horizontal such that the clearance provided between the locking edge and the locking face  14 B of a shelf  14  inserted in the window decreases between a first and a second end of said ramp. 
     In the example shown, the locking edge  16 B actually has two ramps, respectively  17 A,  17 B which form an upside-down V whose angle at its tip is very wide (e.g. about 178°), the first ends of the ramps being situated in a middle portion of the locking edge  16 B, substantially at the place where the clearance j 1  is indicated, while their second ends are situated in the vicinities respectively of the front end and of the rear end of the locking edge, in the depth direction of the unit. 
     FIGS. 6 and 7 show a second embodiment. FIG. 6 shows the end  15 A of a shelf  14 , as inserted in a window  116 . The shape of the uprights is substantially analogous to that of the uprights shown in FIG. 1 to  5 , and the same I-structure is shown for the wall elements  118  situated between two consecutive windows  116 . 
     The bottom edge  116 A of each of the windows is horizontal and forms a bearing surface for a shelf. The differences between the embodiment shown in FIGS. 1 to  5  and the embodiment shown in FIG. 6 lie in the disposition of each of the locking elements and in the shape of the locking edges. 
     Unlike the locking edges  16 B of the first embodiment, the locking edges  116 B are substantially horizontal. The number of locking elements  120  is also substantially two per shelf end. FIG. 6 is interrupted in a region in the middle of the unit, in the depth direction. It can be completed by symmetry about the vertical line C. 
     The locking elements  120  also include wedge-shaped clamping elements  121 , the top faces of which slope. The wedge is integral with a stud  130  suitable for being mounted in the vicinity of the locking edge  116 B of the window, so that the wedge  121  can be inserted into the clearance j provided between the locking edge  116 B and the locking face  14 B of the shelf that is inserted in said window, by being swung about the substantially vertical axis A of said stud. 
     For the purpose of fixing the locking element to the wall element  118 , said wall element is provided with a recess forming a sleeve  132  that is open facing downwards. Optionally, means are provided for retaining the stud in the sleeve. For example, the stud may be engaged under force into the sleeve, and it may optionally be provided with an annular retaining bead. The wedge  121  is connected to the stud  130  via a connection arm  134 , so that the locking element is formed in a single piece. Said arm is of relatively small thickness so as to impart flexibility to the part. 
     Advantageously, the locking elements are provided with handling surfaces. Thus, the locking element  120  shown in FIGS. 6 and 7 may be provided with a substantially vertical tab  136  on that one of its faces which is rearmost relative to the direction in which the locking element is swung to lock the shelf by means of the wedge. Similarly, the flanges  24  and  25  of the locking element  20  shown in FIG. 5 are disposed to project from the sides so as to make the element easier for the user to grasp for the purpose of sliding it. 
     FIG. 8 is a view analogous to FIG. 6 showing another embodiment. The windows  216  are analogous to the windows  116 , the clearance j being provided between the top face  14 B of the shelf  14  and the locking edge  216 B. The clamping element  220  includes a knurled wheel  221  that is carried by a threaded rod  224 . This rod co-operates with a nut  226  which is secured to or integral with the locking edge  216 B. For example, the nut may be implemented in the form of a tapped sleeve formed in one piece with the wall element  218  of the upright. It should be understood that the knurled wheel  221  is suitable for being moved towards or away from the locking edge  216 B by tightening or loosening the threaded rod in said nut. The knurled wheel can thus co-operate with the top face  14 B of the shelf  14  to lock said face relative to the upright.