Telescoping Shelf Assembly

Abstract

A lightweight, sturdy, shelving assembly is disclosed, having telescoping metal shelf and guard rail units which snap fit between (right and left) end brackets, provided with hook ends at their bases to engage spaced upright slotted rails. The lateral span of the shelving assembly is adjustable to fit the desired space. The vertical spacing between the shelves and their guard rails is adjustable after installation to accommodate different sizes of articles. The shelf units are identical pairs having slotted box flanges, one larger than the other, which telescope together with the larger flange receiving the smaller flange of each as the planar surfaces overlap. Each have rolled front and rear box flanges and are identical. The guard rail units are identical pairs formed as rolled poly-sided beams. Each beam has an open-ended slot along one corner whereby two such units, oriented 180.degree. from each other along their longitudinal axes, receive on another in telescoping relationship, with the slot of each receiving a continuous wall of the other. The distal ends of the guard rail brackets have tabs snap-engaging the open extended ends of the guard units. The shelf brackets are provided with a supporting inner flange having distal tabs engaging appropriate openings in the inside walls of the ends of the box flanges of the shelf units.

Description

RELATED PATENTS

This application is directed to improvements over the tray shelving disclosed in U.S. Pat. No. 2,982,423 by Milton E. Handler and Ralph J. Bellon, and U.S. Pat. No. 3,139,258 by the same inventors, both of which patents are assigned to the instant assignee, and the latter being based on an application which was a continuation-in-part of the former.

BACKGROUND OF THE INVENTION

The tray shelving of U.S. Pat. No. 2,982,423 can be easily assembled and dis-assembled, and provides both internal and external bracing with dividers for reinforcing and stability. This shelving is suited for longevity under conditions of heavy use. A telescoping arrangement of non-identical guard rails and trays is disclosed with the end walls having ears with extensions that engage spaced elongated slots in the connecting wall of a U-shaped vertical support element.

The tray shelving of U.S. Pat. No. 3,139,258 can likewise be easily assembled and adjusted due to the upper and lower coplanar ears and their extensions on the bracket elements cooperating with the spaced slots in the inverted channel portion of the support elements. Here also male and female telescoping guard rails and shelf units are disclosed.

SUMMARY OF THE INVENTION

The instant invention comprises certain improvements and simplifications over the structures shown in said prior patents, wherein full advantage of the telescoping feature of the shelves and guard rails is attained without multiplying the number of parts involved, and at the same time, reducing the number of steps in the manufacture while retaining the strength, rigidity and ease of assembly. This is accomplished by fabricating the shelf and guard rail in identical pairs so that, though the pairs of shelf parts telescope along their flanges, the appearance of the shelf externally is that of a single unit. Likewise, the guard rail units fit together in such a manner that the cross-sectional configuration of the telescoped portions is hardly larger than the extending untelescoped portions. Not only are the parts easily assembled in their telescoping relationship, the rigidity of the telescoping parts is enhanced while their attachment to the respective brackets is facilitated.

DESCRIPTION OF THE DRAWINGS

An embodiment of the invention is shown in the drawings wherein:

FIG. 1 is a perspective view of an assembled series of three shelves and guard rails;

FIG. 2 is a partial cross-sectional view along the line 2--2 of FIG. 1;

FIG. 3 is a fragmentary cross-sectional view along the lines 3--3 of FIG. 2;

FIG. 4 is a fragmentary cross-sectional view along the lines 4--4 of FIG. 2;

FIG. 5 is a cross-sectional view along the lines 5--5 of FIG. 3;

FIG. 6 is a cross-sectional view along the lines 6--6 of FIG. 4;

FIG. 6A is an end view of one of the guard rail units to show the spaced relationship of the walls in better detail;

FIG. 7 is a fragmentary perspective view illustrating the manner of attachment of one end of the shelf to one of the support brackets;

FIG. 7A is a plan view of a blank sheet of metal from which a shelf unit is formed;

FIG. 8 is an exploded view of an embodiment of this invention to illustrate the general organization of the parts; and

FIG. 8A is a fragmentary enlarged perspective view of the end of one of the guard rail brackets to show the tabs in more detail.

THE PREFERRED EMBODIMENT

Referring to FIG. 1 a shelf assembly as shown comprising the pair of upright supports or rails 12 having end caps 14, attached in selected spaced vertical relationship upon the supporting wall 16, the pair of guard rail brackets 20 and 20', the guard rail assembly 22, the pair of shelf brackets 24 and 24' and the shelf assembly 26. The remaining bracket, guard rail and shelf assemblies of FIG. 1 are for the purpose of illustrating that any member of said units can be attached to a given pair of upright supports 12 and the distance between a shelf and its guard rail, a shelf and the guard rail thereunder and the over-all vertical spacing of the units are subject to variation as desired in accordance with the placement in relation to the vertical slots 28 (see FIG. 8) in the rails.

The rails 12 are generally U-shaped in cross-section to include the parallel spaced side walls 30 and 32 (FIG. 8), the pair of spaced coplanar front walls 34 and 36, joined by the arcuate connecting wall 38 which has the slots 28 cut therein at desired equally spaced intervals. The bracket member 40 is illustrative of means for attaching the rails to wall or other planar supporting surfaces in a manner which is simple and allows the entire assembly to be easily taken down or rearranged laterally to accommodate different sizes of articles. The wall bracket member 40 comprises the flat base 42 integral with the projecting side walls 44, of equal depth, and the hook member 46 located substantially centrally between the side walls 44 and projecting outward from the base 42 a distance sufficient to engage a rail slot 28 with the upright hook portion 48 thereof engaged on the frontal top edge of said slot. A wood screw 50 serves to hold the wall bracket to the wall. The side walls 44 fit inside the walls 30-32 of the rails and abut against the inside surfaces of the intermediate walls 34-36 in a locked supporting relationship (see FIG. 2). The wall bracket member 40 does not form a part of this invention and any means can be used to fasten the uprights to the walls. A bracket 40 or the equivalent is used at the top and bottom of each of the rails 12 in order to orient same flush against the wall 16 in weight-supporting vertical parallel relationship. The uprights are readily removed by sliding them upward to disengage the hook 48 from the slot 28 which is longer than the vertical height of the flat hook member 46.

Another optional and commonly used part of the assembly is the end plug 14, formed of molded plastic, which fits into the open ends of the uprights as a finish trim piece. Various designs of these end plugs are known in the art provided with tabs 52 which engage within the open channels between the walls 30 and 32 in a snap-fit relationship.

The guard rail brackets 20 and 20' may be formed of any material and for purposes of combined strength and lightness are formed of tough plastic. As shown in FIGS. 2 and 8 the right hand guard rail bracket 20 comprises an elongated arm 54 having the transverse shoulder or boss 56 with a flat end or inside surface 58 from which extends the shank portion 60 having the upstanding tab or hook 62 and the lower tab or hook 64. The inner edges 66 and 67 of the hooks 62 and 64, respectively, are coplanar and normal to the longitudinal axis of the arm 54.

Referring to FIGS. 2 and 4, it is apparent that the bracket 20 is easily attached during insertion of the tab 62 into a slot 28, by tilting the arm 54 so that the tab 62 clears the top and bottom edges of the slot 28. Then, as the arm 54 is pivoted to the horzontal and moved downwardly, the lower hook 64 engages over the bottom edge of the slot 28. The tab 62, being longer, still engages behind the wall 38 at the top of the slot. At the same time, since the distance between the inside surface 58 of the flange 56 and the inner surfaces 66 and 67 of both tabs 62 and 64 is substantially the same as the spaced relationship of the front walls 34-36 from the inner surface of the wall 38, the bracket is squared to the rail and extends rigidly therefrom.

At the distal end of the arm 54, and spaced from the end, top and bottom edges, there is provided a pair of tabs 72-74, facing normal to the inner side (FIGS. 2 and 8) which engage in a force fit relationship within the open end 76 of one member 78 of the guard rail assembly 22. The cross-sectional area of the opening 76 is no greater than the space area around the tabs 72 and 74 so that the end edges of the member 78 abut against the arm 54 and are not exposed. The guard rail bracket 20' is the mirror image of bracket 20 in order to form the support for the other end of the guard rail assembly 22. Consequently, the details of its structure need not be set forth or can be inferred from the description of bracket 20.

In FIG. 8 the tabs 72 and 74 are illustrated as being essentially rectilinear spaced equal sized protuberances extending from the inside surface of the arm 54, near the end thereof. Since the guard rails 78 are made of rolled sheet metal the walls thereof have a certain resiliency at the open end and the pair of tabs 72 and 74, made of plastic, are readily sized so as to snap-fit into the open end 76. Since the hook 62 is held by the U-shaped wall 38 against lateral thrust, the guard rail brackets 20 and 20' are substantially rigid once affixed in the rails 12. The guard rail assembly 22 can thus be extended to fit between the distal ends of the pair of guard rail brackets and be held by the tabs 72 and 74 against displacement.

A modification of this structure is shown in FIG. 8A wherein the end of the arm 54 is provided with spaced tabs 80 and 82 which have oppositely curved tips 84 and 86 which function to engage the inner edges of the opening 76 causing a simultaneous spreading action on the walls and a compression action on the tabs as they are inserted. Also, the four bosses 88 are provided in spaced corner relationship around the base of the tabs 80 and 82 to form a margin against the outer surfaces of the walls of the guard rail unit 78 and further prevent lateral or vertical displacement. The effective outside area of the spaced curved ends 84-86 is slightly greater than the unsprung area of the opening 76. while the effective inner area between the bosses 88 is slightly greater than or substantially equal to the outer sprung area of the end of each guard rail unit 78. The open ends 76 are thus subject to combined and cooperating expanding and contracting forces to form a solid seat against the inside of the arms 54. The guard rail bracket 20' would be similarly modified in this embodiment although it is apparent that the modified guard rail brackets are inter-changeable with that shown in FIG. 8.

As shown in FIGS. 6 and 8, the members 78 and 78' comprising the guard rail assembly 22 are identical. In FIG. 6 these members are shown in telescoping relationship while FIG. 6A shows an end view of one of the rail members so that the walls thereof and their spacing can be identified. It is to be understood that the guard rails 78 and 78' once assembled or telescoped can be used in any quarter-turn orientation to receive the tabs 72 and 74 on tabs 80 and 82 in the openings 76.

Referring to FIG. 6A an end of the guard rails 78 (or 78') is shown to include an internal partial wall 90, the interconnecting side walls 92, 94, 96 and 98 with the latter having a rolled-over edge portion 100. The walls 94, 96 and 98 are of substantially equal width and the sum of the combined thickness of the wall 98, its rolled over-portion 100, the space 102, between it and the partial wall 90, and the width of the wall 92 is about the same as the wall 96 so that an essentially square configuration is formed. Uniformity in wall width or an exactly square configuration is not essential to the invention and it is obvious that in roll-forming a tubular member such as this that all of the corners will not or need not be 90.degree. angles. The edge of the wall 90 terminates short of the inside surface of the wall 96 as indicated by the space 104, which like the space 102, is at least as great as and preferably slightly greater than the thickness of the sheet metal used in the fabrication. It is apparent that some latitude in these spaces is permissible because all of the walls have a spring action along their lengths. The end view of FIG. 6A may also represent a cross-sectional configuration of these wall parts at any point along the length of these members. Although a square or rectangular configuration has been illustrated, these parts may be fabricated in any tubular configuration. The opening 76 extends the entire length of the guard rail members for interconnecting telescoping relationship as will be described in reference to FIG. 6.

In FIG. 6, there is shown the relationship of the walls of a pair of telescoped guard rails 78 and 78'. For simplicity not all of the walls of the guard rail 78 bear reference numbers and in the following description reference to FIG. 6A can be made to identify the parts. It is seen that the internal partial wall 90' of guard rail unit 78' is inside and oppositely oriented to the wall 90 of guard rail 78. The wall 92' passes through the space 104 and the wall 94' extends between the walls 90 and 98 through the space 102, while the wall 96' emerges and with wall 98' completes the configuration. The wall 94 of guard rail unit 78 passes through the space between the wall 98' and 92'. The space 106 has been correspondingly reduced in size over the end space or opening 76.

It is also apparent from FIG. 6 that two outside walls of each of the telescoped guard rail units, which constitute the guard rail assembly 22 present two adjacent walls on the outside. Accordingly, by grasping the guard rail assembly with the finger tips of one hand against an adjacent pair of these walls and the fingers of the other hand against the other pair of walls and moving the hands in opposite axial directions as indicated by the arrow 108 (FIG. 8), the length of the guard rail assembly can be adjusted to the desired amount. In this manner, after a pair of guard rail supports 20 are attached to the desired slots 28 in the rails 12, the tabs 72 and 74 (or 80 and 82) thereon are readily pressed into the openings 76 at each end, in the manner shown in FIGS. 1 and 4.

The shelf brackets 24 and 24', like brackets 20 and 20' are identical but opposite, being mirror images of each other. The description of one will suffice for both. In FIGS. 2, 7 and 8 it is seen that the bracket 24 has the arm 110 extending normally from the base flange 112, the back side 114 of which is flat and normal to the longitudinal axis of the arm 110. The base flange 112 is about the same width as the rail 12 and has the protruding shank 116 central of the rear side 114 with the downward projecting hook 118 formed thereon. The arm 110 projects from the inner edge of the base flange 112. The inner edge 120 of the hook 118 is parallel to the back side 114 and spaced therefrom a distance about equal to the thickness of the rail between the back side of the wall 38 and the front walls 34-36. The outer surfaces of the arm 110 are provided with a rectangular trim flange 122 defining a planar surface 124 into which a trim panel of wood grained plastic (not illustrated) is applied by means of pressure-sensitive adhesive, if desired.

The inside portion of the arm 110 of each bracket 24 has peripheral reinforcing edge flange 126 and the supporting flange 128 extending normal to the vertical plane of the arm 110 and also normal to the base flange 112. The forward end of the flange 128 is notched at 130 to form the distal tab 132. The end of the tab 132 is spaced from the extended end 134 of the arm 110. The tab 132 is also spaced from the top and bottom flanges 126 of the arm 110. The flange 128 has a number of marker ribs 136 therealong for the purpose of identifying the spaced orientation of the bracket during assembly.

The back end of the flange 128 extends beyond the base flange 112 and the extended end carries the transverse abutment flange 138 spaced from the end. At this inner edge the notch 140 defines the rearward distal tab 141 in line with the other tab 132. The distance between the notches 130 and 140 is about the same as the effective distance between the box flanges of the shelf assembly as will be described.

Referring to FIGS. 3, 5 and 7 it is seen that the shelf assembly 26 comprises a pair of identical shelf units indicated by the numerals 142 and 142', which units are identical, each having square ends indicated at 144 with longitudinal side box flanges 146 and 148 bordering the object supporting planar rectangular portion 150. For simplicity the further details of the shelf unit 142 will be described, it being understood that the description also applies to the shelf unit 142'.

The side box flanges 146 and 148 are identically formed but oppositely turned or rolled in relation to the planar portion 150, except that the cross-section outside area of one of the flanges, i.e., the box flange 148 is smaller than or about the same as the cross-sectional inside area of the box flange 146. As will be explained, the smaller box flange of one shelf unit fits into the larger box flange of another shelf unit, the latter being reversed end for end to accomplish this, in sliding telescoping relationship.

FIG. 7A shows a plan view of a rectangular sheet metal blank which has been pre-punched or cut to provide the proper relationship of certain openings which are used to hold the shelf to the shelf brackets 24 and 24'. The sheet metal blank provides the planar surface 150 and both sides of the blank including the side borders are finished with the desired coating or paint to produce a simulated wood or other painted surface.

The parallel, spaced broken lines, i.e., the lines 151 and 152 in the respective side borders indicate the fold lines for the formation of the box flanges 146 and 148. Prior to folding, the blank has eight openings formed in the side borders which become oriented adjacent to the planar surface and on opposite sides thereof when the formation of the box flanges is completed.

For purposes of illustration, FIG. 7A is oriented between FIGS. 7 and 8, as if to form the shelf unit 142 therefrom. Accordingly, the lower side border will be used to form the larger box flange 146 while the top side border will be used to form the smaller box flange 148. The spacing between the fold lines 152 is slightly greater than the spacing between the fold line 151 to accomplish this purpose.

The sheet metal blank is cut to provide the notch openings 154 and 156 at the edge 158 and the notch openings 160 and 162 at the edge 164. These notch openings are illustrated as rectangular but it is to be understood that any shape of opening can be used. At the innermost fold lines of each side border, four more openings are provided, namely, the rectangular openings 166 and 168 for the box flange 148 and the rectangular openings 170 and 172 for the box flange 146.

The larger box flange 146 is formed from the bottom side portion of the blank by folding the metal mechanically along the respective fold lines 152 such that the edge 164 (see FIG. 7) defines the elongated space or slot 174 between it and the planar surface 150 thus producing the inner side wall 176, the top wall 178 (see FIG. 8), the outer wall 180, the bottom wall 182 and the inner wall 184, the latter being formed along the innermost of the form lines 152 whereby it is continuous with the planar portion 150.

Similarly, the smaller box flange 148 is formed from the top side portion of the blank by folding the metal mechanically along the respective fold lines 151 in the opposite direction in relation to the flange 146 such that the edge 158 defines the elongated space or slot 186 between it and the planar surface 150 thus providing the inner side wall 188. the bottom wall 190, the outer wall 192, the top wall 194 and the inner wall 196, the latter being formed along the innermost of the form lines 151 whereby it is continuous with the planar portion 150.

In the box flange 146, the inner walls 176 and 184 are essentially coplanar as are the inner walls 188 and 196 of the box flange 148 and both have the respective slots 174 and 186 on opposite sides. Each shelf unit is, by the opposite folding of the box flanges, provided with eight apertures or openings that are oriented adjacent to but equally spaced from each end of the shelf unit. Thus the notch 154 appears on the bottom of the shelf unit 142 in FIG. 7, within the wall 188 of the smaller flange 148 while the opening 166 does not appear, it being in the wall 196 immediately above and appearing in FIG. 8. The opposite opening 170 in the wall 184 is shown in broken lines in FIG. 7 and does not appear in FIG. 8. The opening 160 is on the top side of the shelf unit 142 in FIG. 8 being in wall 176, and opposite the opening 166 which is in the wall 196.

Since the shelf unit 142 is shown telescoped with the shelf unit 142' in FIGS. 7 and 8, the notches or openings 156, 168, 172 and 162 at the other end are hidden and in a non-functional position. However, when partially extended, the end notches and openings of the shelf unit 142' are exposed as will be described.

Accordingly, when the smaller box flange 148 of the shelf unit 142 is telescoped within the larger box flange 146' of the shelf unit 142' and simultaneously the larger box flange 146 of the shelf unit 142 is telescoped over the smaller box flange 148' of the shelf unit 142', the exposed notches and openings of the latter will be oriented as indicated in FIG. 7. Only the lower or underneath pair of notches at one end of one shelf unit and the lower or underneath pair of notches at the other end of the other shelf unit of an assembly 26 are used in attaching the assembly to the shelf brackets 24-24'. To telescope the shelf units together one of them is turned end-for-end and fitted into the other as illustrated.

The telescoped relationship of the shelf units 142 and 142' is illustrated in FIG. 5 wherein the smaller box flange of each shelf unit is within the larger box flange of the other and the slot defined by the edge 164 of the shelf unit 142 allows the passage of the planar portion 150' of the shelf unit 142' and the slot defined by the edge 158' of the shelf unit 142' allows the passage of the planar portion 150 therethrough. For simplicity the various walls of the box flanges are not indicated by numerals in FIG. 5. Thus, at any over-lapping portion of the shelf units, as represented by FIG. 5, the outer walls of the larger of the box flanges of each shelf unit are totally exposed for gripping with the fingers on each side and moving one shelf unit with respect to the other to adjust the length thereof. Such an assembly is readily attached to the fixed brackets 24, by first adjusting the length to span squared ends 144 between a pair of the fixed brackets 24-24' held by the rails 12 to a wall. Then it is only necessary to spread the bottom portions of the flanges at each end of the telescoped unit so that the holes 170 and 154 at one end can encompass the tabs 132 and 141 at the ends of the supporting flange 128 with the end edge flush against the arm 110 and the flat portion 150 resting on top of the flange 128. Correspondingly the holes 154' and 160' of the extended end of the other shelf unit are spread to encompass the tabs of the bracket at the other end. The flanges are readily spread by gripping the shelf in one hand with an inner twisting action at the top of the flanges.

An advantage of this invention is that both the shelf units and guard rails can be packaged and shipped in telescoped condition which takes less shipping space and also makes quick assembly and attachment to the brackets an easy operation. Also a guard rail assembly 22 affixed to its pair of brackets 24 or a shelf assembly affixed to its pair of brackets can be moved to and from any desired position between the rails merely by lifting and tilting these assemblies upwardly and placing them in a new pair of slots.

The invention is not to be limited to any of the dimensions of the parts described herein since it is apparent that both larger and smaller shelf units and guard rail units can be fabricated following the teachings of the specification. Although sheet metal and plastic have been mentioned as the materials of construction, it is equally apparent that other resilient materials can be used to fabricate the parts. By "resilient sheet material" is meant material which can be deformed or bent slightly with ordinary hand pressure or squeezing in order to spread the flanges sufficiently to engage the brackets and affix the shelf units or telescoped shelf assemblies thereto. More or less than a pair of shelf units and guard rail units can also be used in the assembly of the combination of parts. For instance, by telescoping three shelf units together longer spans between the brackets can be accommodated. Actually, one shelf unit 142 and one guard rail unit 78 can be used to form a shelf assembly if desired. It matters not which way the telescoped guard rails or shelf units are moved in relation to one another since the open ends 76 of the guard rails are uniform and a pair of lower opposite openings will be exposed at either ends of the shelf units. Although openings or notches have been disclosed as the means to attach the shelf units or telescoped shelf assemblies to the brackets it is to be understood that any means operative to attach the shelf units or an exposed end thereof to the brackets may be used. Also the manner of attachment of the guard rails can be modified.

Claims

What is claimed is:

1. A shelf assembly including:

a shelf unit of resilient sheet material having a rectangular planar portion between coextensive integral tubular flanges along the longitudinal edges thereof;

each of said flanges extending above and below the plane of said planar portion and presenting internal opposing walls on each side thereof;

apertures in each of said internal walls adjacent to and substantially equally spaced from the ends of said shelf; and

a pair of bracket members having arm portions adapted to be affixed in horizontal spaced coplanar positions from a supporting structure;

said bracket members each having a pair of transversely extending tabs on the inner surfaces of said arm portions adapted to span between and engage within said apertures; and

the resiliency of said shelf unit allowing the effective transverse span between said flanges to be spread so as to engage said apertures over said pairs of tabs.

2. A shelf assembly in accordance with claim 1 wherein:

a pair of said shelf units is provided as a shelf assembly;

a tubular flange on one side of each of said shelf units being smaller in cross-sectional area than the other flange;

the internal opposing wall of said smaller flange having an edge defining an elongated open-ended slot along one side of said planar portion;

the internal opposing wall of said other and larger flange having an edge defining an elongated open-ended slot along the opposite side of said planar portion;

said pair of shelf units being telescoped one upon the other with the smaller flange of one inside the larger flange of the other and said respective slots receiving the integral planar portion of the other whereby the effective length of said shelf assembly is adjustable.

3. A shelf assembly in accordance with claim 1 including:

a second pair of bracket members having arm portions adapted to be affixed in horizontal spaced coplanar positions from said supporting structure above said pair of brackets for said shelf unit, with the extended ends thereof substantially coextensive therewith;

said second pair of brackets each having tab members extending inwardly from the inside and extended end of said arm portions along a longitudinal axis of said shelf unit; and

a tubular guard rail unit adapted to span between and engage at its open ends over said tab members of said pair of bracket members.

4. A shelf assembly in accordance with claim 1 in which:

spaced upright substantially coplanar rail members are provided in fixed positions on said supporting surface to hold said shelf assembly;

said rail members each presenting a pair of upright spaced walls with an inwardly offset connecting wall therebetween;

a series of spaced slots in said connecting wall; and

said bracket members include a base flange at one end of said arm portion with hook means extending therefrom;

said hook means including a downwardly projecting portion the effective length thereof being longer than the vertical opening of said slots and the inner surface of said projecting portions being spaced from said base flange substantially the same distance as the offset of said connecting wall from said pair of upright walls whereby said hook means of said bracket members are engageable through said slots in an upward angular position and said inner surface thereof engages over the bottom of said slots with said base flange abutting same pair of upright walls of said rail members.

5. A shelf assembly in accordance with claim 3 in which:

spaced upright substantially coplanar rail members are provided in fixed positions on said supporting surface to hold said shelf assembly;

said rail members each presenting a pair of upright spaced walls with an inwardly offset connecting wall therebetween;

a series of spaced slots in said connecting wall; and

said second pair of brackets for said guard rail include a base flange at one end of said arm portion with hook means extending therefrom;

said hook means including upwardly and downwardly projecting coplanar hook members the effecting lengths of which are greater than the vertical opening of said slots;

the inner surfaces of said planar hook members being spaced from said base flange substantially the same distances as the offset of said connecting wall from said pair of upright walls, whereby said hook means of said bracket members are engageable through said slots in an upward angular position and said inner surfaces thereof engage over the top and bottom of said slots with said base flange abutting said pair of upright walls of said rail members.

6. A shelf assembly in accordance with claim 3 in which:

a pair of said tubular guard rail units is provided;

said guard rail units being substantially identical and having an encompassing wall with over-lapping terminal edges spaced axially from each other and one edge being spaced inside the other to define an elongated open-ended slot;

said pair of guard rail units being telescoped one upon the other with a portion of the encompassing wall of each within the elongated slot of the other.

7. A shelf assembly in accordance with claim 3 in which:

a pair of said tubular guard rail units is provided;

said rail units being identical and having an encompassing wall with over-lapping terminal edges spaced axially from each other and one edge being spaced inside the other to define an elongated open-ended slot;

said pair of guard rail units being telescoped one upon the other with a portion of the encompassing wall of each within the elongated slot of the other;

a pair of said shelf units is provided as a shelf assembly;

a tubular flange on one side of each of said shelf units being smaller in cross-sectional area than the other flange;

the internal opposing wall of said smaller flange having an edge defining an elongated open-ended slot along one side of said planar portion;

the internal opposing wall of said other and larger flange having an edge defining an elongated open-ended slot along the opposite side of said planar portion;

said pair of shelf units being telescoped one upon the other with the smaller flange of one inside the larger flange of the other and said respective slots receiving the integral planar portion of the other whereby the effective length of said shelf assembly is adjustable.

8. A shelf assembly in accordance with claim 1 in which:

said bracket members include a transverse supporting flange coextensive with said planar portion between said internal opposing walls; and

said tabs extend from and are coplanar with the ends of said supporting flanges.

9. A shelf assembly in accordance with claim 1 in which said resilient sheet material is metal.

10. A shelf assembly in accordance with claim 3 in which said tab members on said second pair of brackets comprise:

a pair of spaced individual resilient protuberances having outwardly curved divergent ends;

said curved ends extending beyond the sides of said tab members and adapted to snap-fit into the open end of said tabular guard rail unit.

11. A shelf assembly including:

a pair of identical shelf units of resilient sheet material;

each of said shelf units having a rectangular planar portion between coextensive integral tubular flanges along the longitudinal edges thereof;

each of said flanges extending above and below the plane of said planar portion and presenting integral opposing walls on each side thereof;

one of said tubular flanges on one side of each of said shelf units being smaller in cross-sectional area than the other flange;

an internal opposing wall of said smaller flange having an edge defining an elongated open-ended slot along the one side of said planar portion;

an internal opposing wall of said other and larger flange having an edge defining an elongated open-ended slot along the opposite side of said planar portion;

said pair of shelf units being telescoped one upon the other in over-lapping relationship with the smaller flange of one inside the larger flange of the other and said respective slots receiving the integral planar portion of the other whereby the effective length of said pair of shelf units is adjustable.

12. A shelf assembly in accordance with claim 11 wherein:

bracket means are provided to engage the ends of said pair of telescoped shelf units to hold same in a substantially horizontal plane from a supporting vertical surface.

13. A shelf assembly in accordance with claim 11 in which:

apertures are provided in each of said internal opposing walls of said tubular flanges adjacent to and substantially equally spaced from the ends of each shelf unit; and

a pair of supporting bracket means is provided, each having oppositely disposed pairs of transverse tab members spaced from the end of said shelf units a distance greater than the spacing of said opposing internal walls of said tubular flanges, whereby the resiliency of said shelf unit allows the effective transverse span between said flanges to spread so as to engage said apertures over said pairs of tab members on the respective bracket means.

14. In a sheet metal shelf assembly the combination of:

a pair of identical shelf units each having a rectangular planar portion between coextensive integral tubular flanges along the longitudinal side edges thereof;

one of said tubular flanges of each of said shelf units being smaller in cross-sectional area than the other;

each of said flanges of a shelf unit extending above and below the plane of said planar portion and presenting internal opposing side walls on each side thereof;

apertures in each of said internal side walls of said shelf units adjacent to and substantially equally spaced from the ends of said shelf units;

said internal opposing walls of said smaller flange of each shelf unit having an edge defining an elongated open-ended slot along one side of said planar portion;

the internal opposing walls of said larger flange of each shelf unit having an edge defining an elongated open-ended slot along the other side of said planar portion;

said pair of shelf units being telescoped one upon the other into a shelf assembly with the smaller flange of one inside the larger flange of the other and said respective slots receiving the integral planar portion of the other whereby the effective length of said shelf assembly is adjustable to expose a pair of said apertures on the same side and at each end of said shelf assembly;

a pair of bracket members having arm portions adapted to be affixed in horizontal spaced coplanar positions from a supporting structure;

said bracket members each having a pair of transversely extending tabs on the inner surface of said arm portions adapted to span between and engage within said exposed apertures of said shelf assembly;

a pair of identical tubular guard rail units;

said guard rail units having an encompassing wall with overlapping terminal edges spaced axially from each other and one edge being spaced inside the other to define an elongated open-ended slot;

said pair of guard rail units being telescoped one upon the other into a guard rail assembly with a portion of the encompassing wall of each within the elongated slot of the other;

a second pair of bracket members having arm portions adapted to be affixed in horizontal spaced coplanar position from said supporting structure above said first pair of bracket members;

said bracket members of said second pair each having a pair of laterally extending tabs on the inner surfaces of said arm portions adapted to span between and engage within the extended ends of said tubular guard rail assembly.

15. A sheet metal shelf assembly in accordance with claim 14 including:

spaced upright substantially coplanar rail members are provided in fixed positions on said supporting surface to hold said shelf assembly;

said rail members each presenting a pair of upright spaced walls with an inwardly offset connecting wall therebetween;

a series of spaced slots in said connecting wall;

said bracket members of said first pair of brackets include a base flange at one end of said arm portion with hook means extending therefrom;

said hook means including a downwardly projecting portion the effective length thereof being longer than the vertical opening of said slots and the inner surface of said projecting portions being spaced from said base flange substantially the same distance as the offset of said connecting wall from said pair of upright walls whereby said hook means of said bracket members are engageable through said slots in an upward angular position and said inner surface thereof engages over the bottom of said slots with said base flange abutting same pair of upright walls of said rain members; and

said second pair of brackets for said guard rail include a base flange at one end of said arm portion with hook means extending therefrom;

said hook means including upwardly and downwardly projecting coplanar hook members the effective lengths of which are greater than the vertical opening of said slots;

the inner surfaces of said planar hook members being spaced from said base flange substantially the same distances as the offset of said connecting wall from said pair of upright walls, whereby said hook means of said bracket members are engageable through said slots in an upward angular position and said inner surfaces thereof engage over the top and bottom of said slots with said base flange abutting said pair of upright walls of said rail members.

16. In a sheet metal shelf assembly the combination of:

a pair of identical shelf units each having a rectangular planar portion between coextensive integral tubular flanges along the longitudinal side edges thereof;

one of said tubular flanges of each of said shelf units being smaller in cross-sectional area than the other;

each of said flanges of a shelf unit extending above and below the plane of said planar portion and presenting internal opposing side walls on each side thereof;

apertures in each of said internal side walls of said shelf units adjacent to and substantially equally spaced from the ends of said shelf units;

said internal opposing walls of said smaller flange of each shelf unit having an edge defining an elongated open-ended slot along one side of said planar portion;

the internal opposing walls of said larger flange of each shelf unit having an edge defining an elongated open-ended slot along the other side of said planar portion;

said pair of shelf units being telescoped one upon the other into a shelf assembly with the smaller flange of one inside the larger flange of the other and said respective slots receiving the integral planar portion of the other whereby the effective length of said shelf assembly is adjustable to expose a pair of said apertures on the same side and at each end of said shelf assembly;

a first pair of bracket members adapted to be affixed in horizontal spaced coplanar positions from a supporting structure;

said bracket members each having tab means adapted to span between and engage said shelf assembly;

a pair of identical tubular guard rail units;

said guard rail units having an encompassing wall with over-lapping terminal edges spaced axially from each other and one edge being spaced inside the other to define an elongated open-ended slot;

said pair of guard rail units being telescoped one upon the other into a guard rail assembly with a portion of the encompassing wall of each within the elongated slot of the other;

a second pair of bracket members adapted to be affixed in horizontal spaced coplanar position from said supporting structure above said first pair of bracket members;

said bracket members having tab means adapted to span between and engage within the extended ends of said tubular guard rail assembly.

17. A sheet metal assembly in accordance with claim 16 in which:

said flanges of said pair of shelf units are rectangular in cross-section;

said guard rail units are rectangular in cross-section; and

the edge of the outermost of said over-lapping walls of said guard rail units is rounded along its length.

18. A shelf assembly comprising:

at least a pair of shelf units of resilient sheet material each having a planar portion between coextensive integral tubular flanges along opposite longitudinal edges thereof;

one of the tubular flanges of a shelf unit being smaller and having an external cross-sectional area which is no greater than the internal cross-sectional area of the other larger tubular flange;

each of said tubular flanges having an internal wall with an edge disposed in spaced relationship along said planar portion and defining an elongated open-ended slot along one side of said planar portion;

each of said open-ended slots being transversely spaced and on opposite sides of said planar portion;

one of said shelf units being telescoped upon the other with its smaller flange inside the larger flange of the other to form an extendable shelf assembly; and

means operative to engage said telescoped shelf units to a supporting bracket are provided at each of the extended ends of said assembly.

19. A shelf assembly in accordance with claim 18 in which:

more than a pair of said shelf units are employed in telescoping relationship.

20. A shelf assembly in accordance with claim 18 in which:

said engaging means are provided on both ends and on opposite sides of said ends whereby each of said shelf units is interchangeable and said engaging means are exposed in any attitude of extension and on either side of said shelf assembly.