US2973175A - Electrical box bracket - Google Patents

Description

Feb. 28, 1961 A. l. APPLETON 2,97 ,175

ELECTRICAL BOX BRACKET Filed Feb. 19, 1958 3 Sheets-Sheet 1 Feb. 28, 1961 A. APPLETON ELECTRICAL BOX BRACKET Filed Feb. 19, 1958 3 Sheets-Sheet 2 INVENTOR ARTHUR I. APPLETON z a f ,%4%- gM ATTYS Feb. 28, 1961 A. 1. APPLETON 2,973,

ELECTRICAL BOX BRACKET Filed Feb. 19, 1958 3 Sheets-Sheet 3 tion taken in connection with ELECTRICAL BOX BRACKET Arthur I. Appleton, Northbrook, Ill. Appleton Electric Co., 1701 Wellington Ave., Chicago 13, Ill.)

'Filed Feb. 19, 1958, Ser. No. 716,136 7 Claims. (Cl. 248-216) ing purposes. This invention has particular, but not exclusive utility in a bracket for electrical boxes, and when so used facilitates permanent installation of the box on a mounting surface, as, for example, on a wood stud or joist.

A further object is to provide an integral nailing prong which is adapted to be formed from flat sheet material into a configuration presenting a barbed toe that may be driven into the support by a hammer blow, and which when so embedded will be anchored by the fibers of the wood against withdrawal. Another object is to provide a mounting bracket having a plurality of such integral nailing prongs, the individual prongs being so arranged asto mutually cooperate in anchoring the bracket to the support.

Another object of the invention is to provide a bracket for electrical boxes which enables mounting the box square and true on the supporting structure. Another object is to provide a permanent mounting bracket carrying out the foregoing objects and which is simple in construction and inexpensive to manufacture.

This application relates to an improvement in certain respects over the fastener shown in the co-pending application for patent of Norton A. Appleton and Arthur I. Appleton, Serial No. 642,858, filed February 27, 1957, now Patent No. 2,917,263, and is a continuation-in-part of application for patent of Arthur I. Appleton, Serial No. 667,889, filed June 25, 1957, now abandoned.

, Other objects will appear from the following descripthe accompanying drawings, wherein:

Figure l is a perspective view of mounting bracket structure;

Fig. 2 is a side view of the box and mounting bracket shown in Figure 1, taken. from the right hand side of Figure 1;

an electrical box and Un d S es Pate Fig. 3 is a front view of the box and bracket, taken in a direction looking at the. face of the electrical box of Figure 1;

Fig. 4 is a side view like Fig. 2, of an alternative form -'of box and mounting bracket structure;

Fig. 5 is a front view of the box and bracket, taken .in a direction looking at the face of the electrical box of Fig. 6 is an enlarged view showing a prong in elevation (and both in upright andembedded positions; Fig. 7 is a transverse view taken in the plane of lines 7-7 of Fig. 6; Y

Fig. 8 isa transverse section taken in the plane of the right in Fig. 17; and

since the invention is adapted appropriate fittings.

.tions (1 8B,D) of each of the stud, while the Fig. 9 is a transverse section taken through the toe in the plane of lines 9-9 of Fig. 6;

. Fig. 10.is a plan view of a further alternative form of mounting bracket for an electrical box;

Fig. 11 is a side view of the bracket and box shown inFig. 10;

Fig. 12 is an end view of in Fig. 10;

Fig. 13 is a view depicting the bracket ofv Figs. 10-12 with the nailing prongs embedded in a wood member;

Fig. 14 is a view in elevation of a further form of box and bracket;

Fig. 15 is a fragmentary side view of the bracket in Fig. 14;

Fig. 16 is an end view of the bracket and box taken the bracket and box shown .from below in Fig. 15;

the 'box shown fragmentary;

. Fig. 18 is a side view of the bracket and box from Fig. 19 is an end view of the bracket and box taken from below in Fig. 17.

While the invention has been described in connection -with certain preferred embodiments thereof, it will be understood that it is not intended to be limited to such embodiments but is intended to include all modifications, alternative constructions and equivalents which are in- --cluded within the spirit and scope of the appended claims- Referring to the drawings, the present invention is shown embodied for illustrative purposes in brackets for mounting electrical boxes, although this is exemplary only to be used as a general purpose fastener for attachment of a member to a support of wood or. similar type material. One such exem plary bracket 10 embodying the invention is shown in 'Figs. l3,,wherein the box 11 is a conventional switch box, having the usual tapered bottom 12 and knock-outs -13 in the walls which provide openings through which electrical conduit or cable may enter the box through In this case the mounting bracket 10 includes plates 15, 15A formed integral with the heavy gauge metal of the side wall 16 of the box lluat opposite edges and extending outwardly so as to be positionable against the support. It will be evident that whereas in the illustrated form the bracket plates 15,

15A are integral, with the side wall, these may be made separately and fastened to the box structure.

This bracket is adapted for mounting the box on the corner of a stud or joist, and accordingly, the bracket plates 15,

15A have right angle sections ISA-D. One of the see plate 15, 15A fits on the edge 11 is flush with the finished wall, as may be observed in these figures, the face of the box extends out from the plane of the sections 18B,D which fit on the edge of the stud.

In accordance with one aspect of this invention, a series of similar deformable barbed nailing prongs 20 are struck out of the heavy gauge sheet material of the bracket plates 15,15A. Each of the nailing prongs is so constructed that it may be driven into the supporting structure by a hammer blow, thus securing the bracket to and mounting the box on the support without the use of ordinary .nails or screws.

barbed toe 22 extending toward the bracket plateland terminating ina wedge-shaped tip 23 which lies substanother section 18A,C fits-on the side of the stud. So that the front face 19 of the box swam tially within the opening left in the material of the plate after the nailing prong has been struck therefrom. Thus the toe is drivable into the support as by a series of hammer blows. The curve of the'toe 22 is 'defined'by an are I (Fig. 6) struck from about the hinge point 25 of .the prong. By virtue. of this latter provision, the prong pivots about its hinge while the toe enters the wood,

without exerting substantial reaction force on the bracket at the hinge tending to shift the bracket from its original placement on the support.

It is a major aim hereof to secure the prong 20 against withdrawah'and in carrying out this aspect of the invention the tip 23 of the prong 20 is formed so that the outer surface 26 has a smaller radius of curvature than the arc I, which provides a generally forwardly inclined or raked surface, relative to the axis of the prong. It has been observed that when so constructed, the tip 23 acts against the fibers of the wood in such a manner as to draw the curved toe along a path defined by the arc I, and in forcing the tip toward the hinge point defeats any tendency to straighten out the toe. This enhances the holding power of the prong due to the claw effect produced by the prong when fully embedded.

Further in keeping with the invention, the prongs are mounted in cooperative relation so that when the associated'prongs on a bracket are hammered into a wood support, the curved toes enter the wood support at oppositely inclined angles and extend either toward each other or away from each other which accentuates the holding power of the assembly. Thus, when embedded the associated prongs anchor each other. For this purpose, referring to Figs. 1-3, a single prong 20 is struck out of each angle bracket section ISA-D in such a fashion that the prongs are hinged at mutually opposite ends of the corner bracket with the toe portions set oppositely and facing in different directions; as herein shown the toes are in generally facing relation.

In addition to offering greater holding power due to the increased length of barbed edge embedded in the wood, this arrangement of prongs providm greater resistance to forces applied offset from the axis of the prong and effective to shift the bracket laterally on the surface of the support. Such forces would otherwise result in twistingthe nailing prong 20- about its own axis, but, instead, are transmitted as a couple directly to the bracket structure through the mutual cooperation of the prongs 20.

Turning now to further details of the nailing prongs 2 as illustrated in Figs. 2 and 3, for example. In the present instance, the prongs are made with a continuous longitudinal taper from the hinge 25 to the free end or tip 23, leaving a tapered opening 24 in the bracket. To assist in anchoring the prong in the wood, the toe 22 is fashioned on its lateral edges with barbs Z7, and due to the continuous taper, each succeeding barb 27 from the tip back lies at an increasingly greater distance from the center line of the prong. 7 Thus each succeeding barb is in engagement with the wood after the fibers are parted and the toe has been embedded.

As shown in these figures, the tip 23 is angled to enter the support through the opening 24 in the member. Due to the taper of the prong, with the tip 23 in line substantially with the mid-point of the opening, clearance is left between the prong and the lateral edges 24- of the opening. The shank 2.1 and toe 22 may be formed with a'transverse curve as shown in Fig. 9 for stiffening or strengthening purposes, and which is also eifectivefor reducing the width of the prong providing suflicient addipivotable freely about its edge while the prong is driven into the sup o t by h mme blow a p i t sheaisith the Pre nt inventive a a tass i taken of a virtualiy inevitable lack of coincidence between the shank screws,

21 and the opening as the shank moves down into the opening when the prong 20 is driven into the support, as well as a flattening of the transverse curve in the prong shank which may be produced by the hammer blows. The lack of coincidence may be due to several factors, including the non -precise hammering of a workman who may render slanting or glancing blows. Another factor may be the mechanical difficulty in returning the material to the exact form it had originally when the prongs were struck therefrom as by a die in a punch press. Due to the foregoing, one edge or the other of the shank, of a portion of one edge, overlaps the lateral edge of the opening, and the overlapping edges are swaged into mutual engagement by the hammer blows as shown in Fig. 8. As a result the shank 21 is wedged tightly into the opening 24 and is gripped by the edges of the opening. With this arrangement, when embedded the prong is attached to the bracket plate not solely at the hinge but by the shank, and this produces a more rigid connection between the prong and plate. It is particularly noticeable that by reason of the tight fit of the shank in the slot, the bracket is held more securely against sidewise and twisting forces applied in the plane of the bracket plate. Such forces twisting the bracket or tending to move it are transmitted between the toe of the prong and the bracket through the lateral abutting edges of the slot and the shank, making for a stronger connection. Moreover, the stresses within the prongs are effectively reduced giving the effect of greater strength as well as a more rigid connection.

In the bracket shown in Figs. 1-3, due to the angular relation between the plate sections 18A-D, the tangs 20 enter the wood in planes substantially at right angles and derive great holding power therefrom, as well as from the effect the associated prongs have in mutually anchoring each other. Thus, this bracket with the driven prongs cooperating provides a permanent mounting for the box without other securing devices such as nails or screws.

It is preferred, as shown in the figures, to construct the prongs so that the tip of the prong extends slightly beyond the plane of the surface of the bracket plate which is adapted to be positioned against the support. With this arrangement, when the bracket is placed against the support, the tip of the prong projects enough to scratch into the support surface, particularlywhcre it is a relatively soft material like wood, to frictionally hold the bracket against accidental movement until the prong is sufficiently embedded to serve as an anchor.

A further form of bracket embodying nailing prongs constructed and arranged in keeping with the present invention is shown in Figs. 4 and 5. In these figures, a abracket 30 for side mounting is shown-comprised of a pair of alined bracket plates 31, 31A, again formed integral with one side wall 32 of the box 33 to extend therefrom so as to be positionable against the support. For the purpose of providing means to fasten the bracket 30 to a wooden stud or joist without the use of nails or in carryingout the invention a series of integral nailing prongs 20 are struck from the material of the plates. The individual prongs 20 in structure are substantially identical with the prongs 20 just described in connection with Figs. 1-3 and 610, and similar reference numerals are therefore employed.

However, whereas in the instance of Figs. 1-3 the bracket has right angle sections, in the case of the bracket 30 shown in Figs. 4 and 5 the bracket plates 31, 31A are entirely fiat. Therefore, the under sides of the bracket plates are adapted to be positioned against the side of the support, and the prongs 20 are so constructed that they may be driven into the surface of the support by a hammer. After being driven in, the prongs cooperate to rigidly fasten the bracket to the support without the aid .of

n s sc w or th l k In this form of the invention, the prongs 2 0 are a rranged in pairs, with the individual prongs of each pair .plate 41,

parallel and in a generallyfacing relation. To accomplish the latter, the individual prongs (Fig. 5) are positioned such that the shanks 21 of the individual prongs of a pair are hinged at spaced points 32, 33 to the respective bracket plate. Thus, when both prongs are embedded (Fig. 13) the curved barbed toe portions extend away from each other due to the reverse curve set in the prongs, the associated prongs being mutually effective in anchoring each other to the support and gaining additional holding power as a consequence.

A further form of bracket constructed in keeping with the present invention is shown in Figs. -13. In these figures, a bracket 40 is shown comprised of a single plate 41 which is fastened on one wall of an electrical box 42 such as an outlet box, to extend laterally, and has integral nailing tangs 20A-C struck from the material of the plate 41. In the present instance, the under side of the bracket plate 41 is adapted to be positioned flush against the surface of a wood support, such as a well stud or ceiling joist, and the prongs are so constructed that they may be driven into the support by a blow struck with a hammer. In this case three prongs are employed, a pair of which 20A, 20B are hinged to the bracket plate 41 substantially at the juncture between the plate and the box and the other prong 200 being arranged to face the pair. Since these prongs are substantially identical individually to the prongs described previously in connection with Figs. 6-9, the detailed description thereof is not repeated.

With the bracket arrangement which is depicted in Figs.

10-13, when the prongs are driven into the wood support,

in the absence of a provision to prevent the same,'it has been observed that the box bends slightly away from the which has the result of leaving the mounted box askew, as shown in dash-dot lines in Fig. 13, due-to the fact that the bracket plate may dish slightly as the prongs are hammered into the support.

Accordingly, in keeping with the invention, the bracket 40 is arranged on the box so that when the prongs 20A-C have been completely embedded the box is square and true with relation to the supporting surface. In the present instance, for this purpose the bracket plate 41 is initially set at a predetermined angle a (Fig. 10) less than a right angle relative to the box 42. It has been observed that with a bracket like that illustrated the box 42 ordinarily bends about 3 away from the plate while the tangs are being driven. Thus in the present instance a=3 and the bracket and box are initiallypositioned at an angle of substantially 87. Accordingly, when the bracket plate dishes as the prongs 20A-C are embedded (Fig. 13), this action pulls the box into a correct position, square and true with relation to the support.

By arranging the prongs with a pair 20A, 20B, side by. side and facing the third prong 20C, advantage is taken of the effect produced from forming the toe portions curved, wherein the single prong anchors the pair due to the reverse cvurve of the facing prongs. In this manner a stronger, more rigid and secure fastener is provided.

A further form of bracket for mounting an electric box, and embodying integral nailing prongs constructed in accordance with the invention, in shown in Figs. 14-16. In this case there is illustrated a mounting bracket 60 for side mounting a switch box 61 similar in form to the box shown in Figs. 4 and 5. In keeping with the invention the nailing prongs 20 are arranged in pairs and parallel to the end walls 62 of the box, thus lying at right angles to the long dimension of the bracket. It will be observed that the prongs 20 are attached to the bracket 60 at mutually opposite hinge points 63, 64 and are in facing relation so as to take advantage of the cooperative anchoring effect which is present between embedded prongs arranged in such an association.

A different arrangement of nailing prongs 20 on a bracket 71 for olfset mounting an electrical box 72 at the corners of a stud or joist is shown in Figs. 17-19.

.In this instance, the bracket has apair of plates fastened :to opposite edges each of which includes right angle secwill be understood the opposite plate is constructed in a similar manner. For nailing the bracket to a support, the prongs 20 are arranged in pairs on the right angle sections 74, 75 of the bracket 71. As a consequence, the individual prongs 20 of each pair are arrangedat right angles to each other. In this case, however, the axes of the individual pron-gs rather than being arranged parallel, as in Fig. l, are at right angles thus increasing the distance between the -toes 22 of associated prongs when embedded so as to enhance the holding power of the mounting and the stability of the box.

It will be appreciated that the individual nailing prongs incorporated in the mounting brackets shown in Figs. 14-16 and Figs. 17-19 are constructed in the manner depicted in detail in Figs. 6-9, and the previous description applicable to these figures is not repeated. These brackets all offer a convenient, quick method of permanent installation of the brackets on a wood support. Moreover, due to the manner of attachment between the individual prongs and the bracket, a more stable and rigid mounting is obtained which isa special feature as applied to such brackets for electrical boxes, but which is important also for general applications of the nailing prongs. The integral nailing prongs provide a method of attachment adapted to widespread use which is more rigid and secure, may be manufactured at less cost, and is easy and convenient to use.

I claim as my invention: I

1. A bracket for nailing an electrical box to a wood support, comprising, in combination, a plate fastened to one wall of the box having a first section' flat against said wall and a second section substantially perpendicular to said first section and extending therefrom so as to be positionable against the support, and a pair of closely adjacent deformable barbed nailing prongs struck out of said plate, each prong including a shank hinged to the plate and extending at an angle therefrom away from the support engaging side thereof and carrying a reversely curved toe extending toward the support so as to be drivable into the support as by a hammer blow, with the toes of said closely adjacent prongs set oppositely to enter a wood support behind said plate at oppositely inclined angles so that one embedded prong of said pair offsets the other to anchor said plate to the wood support, one of said prongs being hinged to the plate and facing away from the box, the driving of said prongs into the support causing the box to bend away from the plate a predetermined angle, said second plate section being initially-set at said predetermined angle less than a right angle relative to said first section and the box so that when said prongs are completely embedded, the box lies square with relation to the support. 7

2. A bracket for nailing an electrical box to a wood support member comprising a plate fastened to one wall of the box, and a pair of closely adjacent L-shaped prongs struck from said plate, each prong having a shank integral with said plate and a toe portion carried thereby pointed toward said plate, with the toe portions of said closely adjacent prongs set oppositely to enter a wood support member behind said plate at oppositely inclined angles so that one embedded prong of said pair offsets the other to anchor said bracket plate to the wood support member.

3. A bracket for nailing an electrical box to a wood support member comprising a pair of plates fastened to one wall of the box at opposite edges, respectively, of said wall, both said plates having sections arranged at right-angles to fit on the corner of said wood support member, and an L-shaped prong struck from each of apes-a s id plate sections, each of said prongs having a shank section with the toe portions of the prongs on adjacent plate sections set at oppositely inclined angles relative to the plate sections carrying the latter so as to enter a wood support member behind said plate sections in perpendicular planes and at oppositely inclined angles, so that one embedded prong of a pair on adjacent plate sections oifsets the other to anchor said plates to the wood support member.

4. A bracket for nailing an electrical box to a wood support member comprising a pair of plates fastened to one wall of the box at opposite edges, respectively, of said wall, and a pair of closely adjacent L-shaped prongs struck from each plate, eaoh prong having a shank integral with the respective plate and a toe portion carried thereby pointed toward the respective plate, with the toe portions of a pair of closely adjacent prongs on one of said plates set oppositely so as to enter a wood support member behind said one plate at oppositely inclined angles so that one embedded prong of each pair offsets the other embedded prong of the same pair to anchor said plates to the wood support member.

5. A fastener comprising a plate member having a section positionable against a wood support, and a tapered prong struck from said seetionof the plate member leaving a tapered opening in said section, said prong having one wider end hinged to the plate member and lateral edges tapering from the said wider hinged end to a narrower free end, and being formed in an upstanding position with a straight shank extending from said'hinged end away from the'support engaging side of the section, anda longitudinally and transversely curved toe carried by said shank pointed toward the support engaging side of said section and angled to enter the support through substantially the 'd-point of said opening in the plate member, said toe in the upstanding position of said prong having clearance with the lateral edges of the mid-point of said opening in said section, so that the 'prong is pivotable about its hinged end by hammer blows struck on theshank to a flattened position with the toe embedded at an inclined angle in the wood support, said shank with the prong in said flattened position having substantially no clearance with the lateral edges of the opening so that said shank is wedged into the opening with the edges swaged into mutual engagement.

6. A fastener comprising a plate member having a section positionable against a wood support and a prong Lstrnek from said section of the member leaving an opening in said member, said prong having a straight shank hinged to said member carrying a longitudinally and transversely curved barbed toe with substantially the entire length inclined at an acute angle relative to the shank and a tip inclined more sharply than said acute angle to enterfthe support through said opening thereby to embed said toe at an inclined angle in said wood support.

7. A fastener comprising a plate member having a section positionable against a wood support, and a tapered prong struck from said section of the plate member leaving a tapered opening in said section, said prong having one wider end hinged to the plate member and lateral edges tapering from the said wider hinged end to a narrower free end, and being formed in an upstanding position with a straight shank extending from said hinged end away from the support engaging side of the section, and a longitudinally and transversely curved barbed toe carried by said shank pointed toward the support engaging side of said section and angled to enter the support through substantially the mid-point of said opening in with the lateral edges of the mid-point of said openingin said'section so'that the prong is pivotable about its "hinged end by hammer blows struck on the shank to a flattened position with the barbed toe embedded at an inclined angle in the wood support, said shank with the prong in said flattened position having substantially no clearance with the lateral edgesof the opening so that said shank is wedged into the opening with the edges swaged into mutual engagement.

References Cited in the file of this patent UNITED STATES PATENTS 1,171,127

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