US2729414A - Bar hanger fixture for outlet boxes - Google Patents

Description

Jan. 3, 1956 E. B. CLARK 2,729,414

BAR HANGER FIXTURE FOR OUTLET BOXES Filed Oct. 28, 1952 Pfg. f,

Inventor: Edward B. Clark United States Patent O 2,729,414 BAR HANGER FIXTURE FOR QUTLET BQXES Edward B. Clark, Milford, Conn., assignor to Genera! Electric Company, a corporation of New York Application October 28, 1952, Serial No. 317,333 2 Claims. (Cl. 248-414) The present invention relates to bar hanger fixtures of the two-piece type used in connection with outlet boxes. Such fixtures comprise a clamp member having an opening through which the bar hanger passes, a stud to which an electrical fixture may be attached, and a screw for fastening the clamp and stud together in an opening in an outlet box and for securing the clamp and outlet box by means of the stud to the bar hanger.

The object of the invention is to provide an improved construction in a two-piece bar hanger xture which has substantial strength and is especially able to resist torsion or bending stresses, but which, at the same time, is handy to use and capable of being manufactured at low cost.

For a consideration of what I believe to be novel and my invention, attention is directed to the following specification and to the claims appended thereto.

In the drawing,

Fig. l is a bottom plan view of an outlet box supported on a bar hanger fixture embodying the invention.

Fig. 2 is a sectional view of the structure shown in Fig. l.

vlFig. 3 is a sectional view taken on line 3 3, Fig. 2, the gure being on a scale larger than that of Fig. 2.

Fig. 4 is a perspective view of two parts of the hanger fixture.

Referring to the drawing, tached at its ends to building attached an outlet box 3 bodying the invention.

The bar hanger fixture comprises a metal clamp 4 which may be of drawn construction and a metal stud 5, which also may be of drawn construction.

Clamp 4 comprises a cylindrical sleeve 6 having openings 7 in which the bar hanger may be positioned, a cylindrical neck 8 of a diameter smaller than that of sleeve 6, a tapered wall 9 which connects sleeve 6 to neck S, and a bottom wall 10 provided with an in-turned ilange 11 to form an opening which is threaded to receive a fixture screw 12.

Stud comprises a cylindrical sleeve 13 threaded on its outer surface and an outwardly flared flange 14 which is dimensioned to surround tapered wall 9. The end of sleeve 13 has a bottom wall 15 provided with a countersunk opening for fixture screw 12. Neck 8 has an outside diameter equal to the inside diameter of sleeve 13 so that it tits snugly therein. As is clear from the drawing, sleeve 6 has an outside diameter such that the sleeve will pass through the knockout opening 16 of an outlet box, and flange 14 has an end diameter such that it will engage with the box wall at the edge of a knockout opening.

1 indicates a bar hanger atstudding 2, and to which is by a bar hanger fixture em- When an outlet box is attached to a bar hanger as shown in the drawing, screw 12 when tightened brings the edge of flange 14 up fast against the inside Wall of the box bottom and pulls clamp 4 down to bring the bar hanger fast against the outside wall of the box bottom. Thus, when tightened, the screw serves to fasten the box tightly to the bar hanger. To hold the two parts of the fixture from turning relatively to each other, tapered wall 9 is provided with two square-sided lanced-out lugs 17 which tit into two square-sided indents 18 in flange 14. This serves to lock the two parts together and to prevent the stud from turning on the clamp when a mounting means is being attached to threaded sleeve 13.

An important feature of my invention is the provision on the clamp of the neck S which projects down inside sleeve 13 so that the tapped opening in neck-wall 10 is close to the opening in wall 15 of the stud. As a result, a relatively short screw can be used and, at the same time, the neck 8 serves to furnish support for the threaded sleeve 13. As a result, the screw, which forms the sole means for holding the structure assembled, is subjected to a minimum of distortion when the stud is subjected to bending and torsion stresses.

What I claim as new and desire to secure by Letters Patent of the United States is:

l. A sheet metal bar hanger xture for attaching an outlet box to a bar hanger including a hollow clamp and a hollow stud, the said hollow clamp comprising a cylindrical sleeve adapted to be positioned in an outlet box knock-out opening, the said sleeve having opposed openings to receive a bar hanger, said clamp also having a cylindrical neck of less diameter than the sleeve with a tapered wall portion joining the said sleeve and neck, said neck having a bottom wall provided with a tapped opening, the said hollow stud comprising an externally-threaded cylindrical sleeve in telescopic engagement with the cylindrical neck of the clamp and an outwardly ilared ange the edge of which is adapted to engage the inner wall of an outlet box, one of said clamp and stud members having one or more lugs which engage within indents formed in the other member to hold the stud from turning relatively to the clamp, the bottom wall of said threaded sleeve having an opening in line with said tapped opening in the neck of the clamp, and a screw which extends through the opening in the bottom wall of the threaded sleeve and threads into the opening in the bottom wall of the neck of the clamp in order to provide the desired clamping action.

2. A bar hanger fixture as recited in claim l wherein the tapered wall portion of the clamp is provided with outwardly projecting lugs which fit into indents formed on the flared flange of the stud in order to hold the stud from turning relatively to the clamp.

References Cited in the tile of this patent UNITED STATES PATENTS 1,723,866 Knoderer Aug. 6, 1929 2,013,059 Leslie Sept. 3, 1935 2,233,334 Austin Feb. 25, 1941 2,260,829 Carlson Oct. 28, 1941 2,365,433 Polizzi Dec. 19, 1944

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