ll! H W l ite @ites ltet 1 3,665,529 Slominslti May 30, 11972 54] FRAME FOR BUX SPRING ASSELY 1,585,279 5/1926 Brandberg ..5/263 [72] lnventor: Walter V. Slommskn, Lexington, Ky. Primary Examiner Bobby R- y [73] Assignee: Hoover Ball and Bearing Company, Saline, Assistant Examiner-Andrew M. Calvert Mich- At!0rney0lsen and Stephenson [22] Filed: July 21, 1970 [21] Appl. No.: 56,933
[57] ABSTRACT [52] US. Cl ..5/264, 267/] l l A box spring frame having side and end rails made of wood [51] Int. Cl ..A47c 23/02 n cros r ils n a uppor bar made of sheet metal. The [58] Field of Search ..5/236, 247, 263, 264, 249; cross rails and the support bar have interlocking means 2 7/ 1 1 1 l 12 formed out of the sheet metal which can be interconnected in a stressed condition as an incident to assembling the [56] References Cited prefabricated parts.
UNITED STATES PATENTS 1,378,921 5/1921 Van Hove ..5/264 R 7 Claims, 7 Drawing Figures PATENTEBMAY 30 I972 INVENTOR WALTER -V. SLOMINSKI ATTORNEYS FRAME FOR BOX SPRING ASSEMBLY CROSS REFERENCE TO RELATED APPLICATION This application relates to the invention disclosed in copending application Ser. No. 886,468, filed Dec. 19, 1969 for Frame for Box Spring Assembly.
FIELD OF THE INVENTION The present invention pertains to an improved frame for box spring assemblies of the type disclosed in US. Pat. No. 3,286,281, issued Nov. 22, 1966 to Walter V. Slominski. In this patent box spring assemblies are disclosed in which the springs are of the formed wire type rather than of the conventional coil type.
As is explained in the aforesaid copending application Ser. No. 886,468, it is conventional practice to make box spring frames from a material such as wood. It has become increasingly difficult to obtain low cost lumber of sufficient high quality to make box spring frames of wood so that it has become highly desirable to make frames of metal or a combination of wood and metal. The present invention is particularly adapted for use with a frame assembly which has side and end rails made of wood and cross rails or slats and a supporting bar made of sheet metal. However, it will be understood that the invention may be used with a box spring frame which is made entirely of metal.
One of the advantages of manufacturing box spring assemblies wherein formed wire springs are used rather than conventional coil-type springs is that the fabricated components for the box spring assemblies can be shipped compactly in unassembled form, and the box spring assemblies can be assembled by the customers at suitable sites. This substantially simplifies the shipping and handling problems involved with box spring assemblies and enables the customers to benefit fully from the economic considerations involved in manufacturing the knocked-down parts at one location and thereafter assembling the prefabricated parts at the location selected by the customer. When operating in this manner, it is highly desirable that the parts of the box spring assembly are fabricated so as to enable easy assembly of the knocked-down parts without the use of rivets, screws or welds.
SUMMARY OF THE INVENTION The present invention provides an improved frame for a box spring assembly which is constructed and arranged to facilitate the assembly of knocked-down parts and to facilitate interconnecting the parts in the most simple and effective manner.
According to a preferred form of the present invention, a frame for a box spring assembly is provided comprising side and end rails made of wood, a longitudinally extending support bar extending between and secured to the end rails, and a plurality of cross rails extending between and supported at longitudinally spaced locations on the side rails and the support bar. The cross rails and the support bar are formed of sheet metal and have interlocking means for holding these parts together. The interlocking means are formed out of the material of the parts and are constructed and arranged so that they can be snapped together in a prestressed condition to assure that they remain interconnected.
In one form of the invention the interlocking means include pairs of tabs facing one another in the cross rails, such tabs being struck out of the material forming the cross rails. The support bar is a generally U-shaped channel in cross section having laterally extending flanges at its upper ends which are adapted to fit between the pairs of tabs struck out of the cross rails. For the purpose of assembling these parts in their interconnected positions, the U-shaped channel can be urged together to permit the flanges to fit within the tabs after which the resilient properties of the channel will urge the flanges outwardly into locked positions relative to the tabs. The tabs can be struck out of the material of the cross rails in a variety of ways within the scope of the present invention.
It is preferred that the cross rails and the support bar be secured to the side and end rails by means of staples or the like, and for this reason, it is desirable that the side and end rails be made of wood, but it is to be understood that the present invention can also be used with side and end rails made from metal.
Thus, it is the principal object of the present invention to provide an improved frame for box spring assemblies.
Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.
BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a top plan view of a box spring assembly embodying the present invention with a portion broken away for clari- FIG. 2 is an enlarged fragmentary top plan view of one form of interconnecting means for holding the cross rails and support bar together;
FIG. 3 is a fragmentary section taken on the lines 3-3 of FIG. 2;
FIG. 4 is a section taken on the lines 44 of FIG. 3;
FIG 4 is a section taken on the lines 4-4 of FIG. 3;
FIG. 5 is an enlarged fragmentary top plan view of a modified form of interlocking means for holding the cross rails and support bar together;
FIG. 6 is a fragmentary section taken on the lines 6-6 of FIG. 5; and
FIG. 7 is a section taken on lines 7 7 of FIG. 6.
Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawing, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing, the embodiment of the invention illustrated in FIGS. l-4 will next be described. The box spring frame 10 is illustrated in assembled relation with the box spring assembly 12 which is of the general type disclosed in the aforementioned US. Pat. No. 3,286,281. The frame 10 comprises a pair of parallel side rails 14 and a pair of parallel end rails 16 which are made of wood. A longitudinally extending center support bar 18 extends between and is stapled as at 20 to the end rails 16. A plurality of cross rails or slats 22 extend between and are supported at longitudinally spaced locations on the side rails 14 and on the support bar 18. The cross rails 22 are suitably secured to the side rails 14 as by means of the staples 24.
The cross rails 22 and the support bar 18 are made of sheet metal. The cross rails define in cross section a U-shaped channel such as can be seen best in FIG. 4, and the support bar 18 defines in cross section a generally U-shaped configuration having laterally outwardly projecting flanges 26 at the upper ends of the U-shaped cross section such as can be seen best in FIG. 3.
The cross rail 22 can be manufactured in one rolling operation so that the pairs of tabs are struck from the sheet metal and are located in spaced relation with the distal ends thereof facing one another. For the purpose of stiffening the tabs they are preferably notched or deformed, as shown in FIG. 4 to oppose longitudinal bending. The support bar 18 can also be formed in a single operation such as by rolling, and it has a transverse configuration so that in an unstressed condition the outer ends of the flanges 26 are normally spaced apart a distance greater than the space between the distal ends of the tabs 28. Thus, when it is desired to interconnect the support bar with the plurality of cross rails 22, this can readily be accomplished by inserting the one flange within one of the tabs 28, as is shown by the dotted line position of the support bar 18 in FIG. 3, and thereafter by urging the flanges together so as to stress the support bar 18, the other of the flanges can be inserted within the other tab 28 to the solid line position shown in FIG. 3. By virtue of this arrangement, the support bar 18 will be in a prestressed condition constantly urging the flanges 26 into interlocked position with respect to the tabs 28.
It is also to be observed that the support bar 18 is secured to the end rails 16 by means of the staples 20 which pass through the flanges 26. When vertical loads are applied against the support bar 18, the latter will tend to bow a limited extent downwardly causing the upper ends of the U-shaped cross section to open wider resulting in a tighter holding action of the interlocked parts.
It will be recognized that other arrangements may be provided within the scope of the present invention for interlocking the support bar 18 and the cross rails 22. One such embodiment is shown in FIGS. 5-7, wherein a support bar 18 is provided which is identically the same as the one described with respect to the embodiment of the invention illustrated in FlGS. 1-4, and a cross rail 22a is disclosed which is essentially the same as the cross rails 22, differing in that tabs 28a are struck out of the material of the cross rails 22a so as to have a different configuration than the tabs 28. As best shown in FIG. 7, the tabs 28a form vertical extensions of the side walls 30 of the U-shaped channel defined by the cross rail 22a. However, in operation, the interlocking means shown in FIGS. 5, 6 and 7 will function essentially the same as the corresponding interlocking means of the embodiment of the invention shown in FIGS. 1-4.
It is claimed:
1. A generally rectangular frame for a box spring assembly comprising connected side and end rails, a longitudinally extending support bar extending between and supported on said end rails, a plurality of cross rails extending between and supported at longitudinally spaced locations on said side rails and on said support bar, pairs of tabs facing in opposite directions struck out of said cross rails, and laterally extending flanges on said support bar held in a stressed condition between the tabs in each said pair of tabs so as to maintain said crossrails and said support bar in interlocked relation.
2. The frame that is defined in claim 1, wherein the tabs of each of said pairs are in spaced relation with the distal ends thereof facing one another, and said support bar has a body portion of a generally U-shaped cross section and laterally outwardly projecting flanges at the upper ends thereof, said flanges fitting into said tabs and being urged thereinto by the prestressed condition of said body portion.
3. The frame that is defined in claim 1, wherein said one interlocked part is adapted to be prestressed as an incident to its being fitted in interlocking relation with the other part.
4. The frame that is defined in claim 2, wherein said crossrails are U-channel members having a bottom wall, said tabs being struck out of said bottom wall so as to be inclined downwardly with respect to the longitudinal axes of said cross rails.
5. The frame that is defined in claim 2 wherein said body portion of a generally U-shaped cross-section has its legs diverging outwardly.
6. The frame that is defined in claim 4, wherein each of said tabs are deformed to stiffen them against bending.
7. The frame that is defined in claim 4, wherein said cross rails are U-channel members having a bottom wall and upright side walls, said tabs being struck out of said bottom wall and deflected so as to be extensions of said upright side walls.