Sheet Metal Shelving Assembly

The present invention relates the filed of bent metal shelving. Despite this field being highly developed, there have always been the problems of increasing strength without the expenditure of additional material, improving the ease of assembly, improving the reliability of the shelf with respect to remaining assembled, and improving safety.

In the prior art, these desirable results or problems, depending upon the viewpoint, have been the subject of invention with varying degrees of success, but there is always room for improvement.

In general, it is an object of the present invention to reduce the above-mentioned problems by correspondingly providing improvements in the mentioned areas. Although the claims are the true measure of the invention, the nut and bolt connection between bent metal columns and shelves: is easy to assemble because the bolt apertures through the shelf skirts are spaced downwardly from the shelf main planar support surface a distance sufficient to permit easy finger access for the nut; is easy to assemble because the skirt includes a return bend portion forming an upwardly facing nut locking surface to prevent rotation of the nut during assembly; is secure because the skirt is formed of spaced apart walls that will compress and bias the nut, bolt assembly, particularly with an interlocking upper portion of the walls to provide or symmetrical compressions; is secure due to the columns being biased or stressed during assembly to bias the nut and bolt threads; and is strengthened in the column margins by bent portions that also increase safety.

Further objects, features and advantages of the present invention will become more clear from the following detailed description of a preferred embodiment, shown in the drawing, wherein:

FIG. 1 is a perspective elevation view of shelving employing the features of the present invention, as seen from line II--II in FIG. 1;

FIG. 3 is a top plan view of one corner as seen from line III--III in FIG. 1; and

FIG. 4 is an enlarged cross-sectional view taken along line IV--IV in FIG. 1.

Essentially, the shelving consists of at least one shelf 1 (two being shown in FIG. 1, although any number may be employed), a column 2 (four being shown in FIG. 1, although more or less may be provided for each shelf, for example when shelving is connected side by side using one column between two adjacent shelves) and fasteners 3 (nuts and bolts being shown, although other compressive type fasteners may be employed according to the broader aspects). In FIG. 1, conventional bracing 4 is shown by way of an example of conventional structure that may be employed with the features of the present invention, although not being necessary. The shelves, columns, and optionally bracing are constructed solely of bent sheet metal, that is each is constructed of a single sheet of metal, preferably thin steel, that is cut and bent into the shape employed. Of course, coatings and the like may be applied on the steel, for example protective and decorative paint, or plastic sleeve feet for the columns, which are conventional features employed by steel shelving.

All of the columns are identical, so that only one is shown in detail. Each column is symmetrical about a vertical center line 5. On each side of the centerline is a side wall 6. Only one side wall is necessary for a shelf, for example two horizontally adjacent shelves may be conncected together by only a single column and therefore two said walls will be associated with one shelf, one of which side walls will be common to the other shelf. Each side wall is provided with one or more through horizontal apertures 7, which are preferably evenly spaced from each other and vertically aligned with respect to each other.

As seen in FIG. 3 in plan view (this view would be substantially the same as a cross-sectional view), the columns are of a W-shape having outermost legs effectively formed by the side walls 6. Innermost legs 9 are perpendicular to each other where they are joined at the centerline 5, and the innermost legs are also perpendicular to the outermost legs 8, where they are integrally joined through a bend along margins opposite to the mutually joined margins at the centerline 5. Each of the outermost legs 8 has a major side wall portion extending from the integral connection with the innermost leg 9 outwardly to a bent margin 10, a transversely extending flange 11, and a U-shaped return terminal flange 12, which may be closed upon itself in a loop as specifically shown in the drawing, all of which are serially connected together. The U-shaped return terminal flange 12 is of a width, as measured perpendicular to the side wall portion 8, substantially equal to the width of the transversely extending flange 10 so that the column side wall 6 may be in its entirety clamped against a planar surface, namely the skirt to be described. Within the range intended, the U-shaped return terminal flange 12 may in fact extend inwardly towards the shelf more than side wall portion 8, so that it may be stressed into the planar condition during assembly, or outwardly beyond the aligned position, or may be of a different width, plus or minus, for similar effects. The main aspects of this feature are that the side walls are capable of being clamped against a vertical planar surface, the terminal edge is reversely bent back and a transverse flange is provided to allow some space for the return terminal flange. The return terminal flange 12 and transverse flange 10 add column strength to a far greater amount than would be proportional to the increased material used and further provide a safe marginal edge so that fingers and the like cannot be easily damaged on the edges.

Preferably, the shelves are identical to each other, so that only one will be described in detail. The shelf has a main planar support portion 14 that is rectangular and horizontally arranged between the four columns, as illustrated, which columns are at the four corners of the rectangle. A plurality of ribs 13 are provided (bent) in the planar support portion 14. These ribs 13 are preferably parallel to each other and preferably extend in the elongated direction of the rectangular planar support portion 14. The shelf includes an integrally formed generally vertically extending or more preferably depending skirt portion 15, preferably along each edge or around the entire periphery of the shelf 1. Each of the four skirts 15 includes, at each of its opposite ends adjacent the shelf corners, at least one through aperture 16, which horizontally extends in alignment with a selected aperture 7 in the adjacent column 2 for the reception of a threaded bolt 17. The bolt 17 has a head 18, which may be provided with a tool engaging portion 19, a slot being illustrated. A nut 20 is threaded on the inside end of the bolt 17 to supportingly clamp the shelf 1 on the column 2. The assembled position is shown in FIG. 4, whereas an exploded or unassembled position is shown in FIG. 3.

All four of the skirts may have the identical construction shown in FIG. 4 in detail, or they may have portions of the structure shown in FIG. 4. Most preferably, the opposed parallel front and rear skirts (along the long dimension of the shelf) are constructed as shown in FIG. 4; whereas the end skirts that are parallel to each other, extend along the short ends of the shelves and are perpendicular to the long skirts, have a more simplified structure to be described.

Preferably, all of the four skirts have the following structure: an upper portion 21 that is integral in one piece with the sheet metal of the planar support portion 14, that is generally of a downwardly opening channel or U-shape; a depending outer wall portion 22, having therein an inwardly extending rib 23 that extends horizontally for the full length of the skirt; and an inwardly and upwardly bent sheet metal portion 24.

For the end skirts, the inwardly and upwardly bent sheet metal portion 24 would be smaller and bent back upon itself (not shown in detail) in the same manner as shown in FIG. 3 with respect to the portions 12.

In addition to that described above, the front and rear skirts have the additional structure shown in FIG. 4, namely: the portion 24 may also be described as an inwardly bent sheet metal lower return portion forming an upper facing nut locking surface 25 spaced from the aperture 16 a distance A. As shown in FIG. 3, one of the nuts 20 has been rotated 90.degree. from its assembly position to illustrate a minimum nut width B defined as the nut thickness perpendicular to the nut axis as measured between the side wall of the threaded hole and the adjacent closest outer side wall of the nut; the maximum nut width thickness is C, which is measured in the same way, but with respect to the maximum thickness. The distance B is at least less than the distance C and substantially equal to the distance A, so that the nut locking surface 25 will, in cooperation with the confining aperture 16 that limits the transverse shifting of the bolt, prevent rotation of the nut 20 after the nut 20 is initially threaded onto the bolt 17 at least to an extent sufficient to permit tightening of the nut and bolt assembly without requiring the placement of a tool on the nut 20. The aperture 16 is located a distance D from the adjacent under surface of the planar support portion 14 that is substantially greater than any of the distances A, B, C, so that the undersurface of the shelf does not limit access, more particularly does not interfere with the fingers gripping the nut 20 during initial assembly of the nut 20 onto the bolt 17, to facilitate assembly. Therefore, the nut may be easily initially threaded onto the bolt passing through the aligned apertures 16 in the skirt and 7 in the column and thereafter the nut 20 will not turn when tightened and will hold against turning due to positive interference between the nut maximum width portion and the nut locking surface 25.

The above-mentioned skirt lower return portion 24 may be described as being generally of J-shape, with the long leg 26 and short leg 27 of the J-shape being horizontal. The short leg 27 forms the upwardly facing nut locking surface 25 (in a more simplified version, for example with respect to the end skirts, the nut locking surface 25 may be merely the edge of the web 28 of what is shown as the J-shape in FIG. 4, this modification not being shown). The skirt portion further includes an upwardly extending inner wall portion 29 generally coextensive with, spaced from and parallel to the outer wall portion 22 and having a through aperture 16 therein aligned with the aperture 16 in the outer wall portion 22 for receiving the bolt 17. Therefore, it may be seen that tightening of the nut and bolt will compress the inner wall portion 29 and the outer wall portion 22 towards each other in a resilient manner to thereby exert a bias on the threads of the assembled nut and bolt to resist disassembly much in the same manner that a Belleville washer or other lock type washer will exert a bias on a nut and bolt assembly to resist disassembly. Therefore, a lock washer is not needed. In fact, no washers are needed.

The skirt portion as shown in FIG. 4 further includes a terminal flange 30 integrally extending outwardly from the uppermost portion of the inner wall portion 29 and generally horizontally to the inside surface of the outer wall portion 22, so that compression of the inner wall portion 29 and outer wall portion 22 by tightening the nut and bolt will symmetrically compress the inner and outer wall portions 29, 22 only at their mid portions as the uppermost and lowermost portions of the inner and outer walls 29, 22 are respectively held at their initial spacing by the lower return portion 24 and the upper terminal flange 30.

The planar support portion 14 of the shelf 1 includes an upwardly extending integral rib 31 at least for the skirt shown in FIG. 4, preferably for both the front and rear skirts, and most preferably for all four skirts or for all four edges of the shelf or around the entire periphery of the shelf. At least for a skirt structure as shown in FIG. 4, this rib 31 will nestingly receive therein the terminal return flange 30 in an interlocking manner. Thereby, the upwardly extending integral rib 31, in addition to receiving in a locking manner the return flange 30, also both reinforces the shelf by increasing its beam strength and forms an upwardly extending ledge around the periphery of the shelf to resist sliding movement of articles supported on the shelf in a direction off the periphery of the shelf.

As shown in FIG. 4, the rib 23 has the additional function of matching the strengthening characteristic provided by the leg 27, which is generally parallel to it and horizontally aligned. Because of this strengthening matched for the inner wall portion 29 and outer wall portion 22, the symmetry of the clamping provided by the bolt is improved.

As shown in FIG. 3, which is true with respect to all four corners, adjacent depending skirt portions at each corner of the shelf are spaced from each other to receive therebetween the innermost legs 9 of the adjacent column 2. Effectively, a notch is formed at each corner of each shelf to mate with the shape of the innermost legs 9. Preferably, the column is bent and fixed into the shape shown in the unassembled condition of FIG. 3, wherein the angle formed between the outermost legs is sufficiently obtuse that when the column is assembled the outermost legs 8 will be resiliently bent to a generally right angular relationship to thereby exert a bias on the threads of the assembled nut and bolt to resist disassembly of the nut and bolt in the manner of a lock washer. That is, there is a perpendicular orientation of the outermost legs 8 and innermost legs 9 when assembled, but these legs have an orientation from the assembled perpendicular orientation toward a planar relationship when in the relaxed unassembled position shown in FIG. 3 so that when assembled each column will exert a bias on the threads of the assembled nut and bolt to resist disassembly.

The operation, advantages and functions of the preferred embodiment have been set forth along with illustrated variations. Further embodiments, modifications and variations are contemplated in addition to the advantageous details, all in accordance with the spirit and scope of the following claims.