US1310191A - Electrical fitting - Google Patents

Description

C. R. HUBBARD AND D. M COOPER.

ELECTRICAL FITTING. APPLICATION FILED FEB 2. 1918.

1 ,81 0, 1 91. Patented July 15, 1919.

INVENTOR THE coLuMmA PLANOURAPH co., WASHINGTON, B. C.

WITNESSES UNITED STATES PATENT curios.

CECIL R. HUBBARD, OF BADEN, AND DAVID M. COOPER, OF AMBRIDGE, PENNSYLVANIA,

ASSIGNORS TO NATIONAL METAL MOLDING COMPANY, OF PITTSBURGH, PENNSYL- VANIA, A CORPORATION OF PENNSYLVANIA.

ELECTRICAL FITTING.

Application filed February 2, 1918.

To all whom it may concern:

Be it known that we, CECIL R. HUBBARD,

. residing at Baden, in the county of Beaver and State of Pennsylvania, a subject of the King of Great Britain, and DAVID M. COOPER, residing at Ambridge, inthe county of Beaver and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful Improvements in Electrical Fittings, of which improvements the following is a specification.

Our invention relates to electrical fittings such as lamp sockets, receptacles, attachment plugs, etc., which fittings include in their construction base blocks of insulation and metal caps inclosing the tops of such blocks.

As such fittings are usually constructed, the attachment of the caps to the base-blocks is effected by screws extending through the caps and engaging nuts secured within the body of the blocks. For securing such nuts in the base blocks of insulation, the blocks are provided with holes extending from the back to the front, the back portions of the holes being square in cross-section to receive the nuts and the front portions being round to receive screws. The nuts, which are in serted in the square portions ofthe holes and rest on the shoulders or ofi'sets between the square and round portions areseal'ed in place by wax or other suitable material,

There are various difficulties incident to such means of attaching the caps to the base blocks. For example, the nuts are liable to be loosened and removed .from their holes by reason of pressure on the top of them exerted through the round portions of the holes. Also, long screws are required for attaching the caps, and it is diflicult to locate the holes by the screws when the latter are inserted through the screw holes of the caps.

It is the object of our invention to provide, for electrical fittings of the character described, improved means for attaching the caps to the bases whereby the above-mentioned and other diificulties may be overcome.

In the accompanying sheet of drawings which forms part of our specification. Fig ure 1 is a longitudinal central sectional view of an electrical fitting, embodying the Specification of Letters Patent.

Patented July 15, 1919. Serial No. 215,165,

preferred form of our invention; Fig. 2 a side view of the lower portion of such fitting and Fig. 3 a perspective view of a detail of construction to which reference is made hereinafter.

In the practice of our invention, we provide the base block of insulation with an attaching lug or member, a portion of which extends above the top of such block and is provided with means for engaging an attaching member extending through the cap. The base block and lug are preferably provided with cooperating thrust and bearing faces so arranged that a push or a pull upon the lug will be resisted directly by the base block rather than by the wax or other material which may be used to hold the lug in fixed position.

In the illustrated embodiment of our invention there is shown a base block of insulation 1 and a metal cap 2 which form part of a lamp socket. For the sake of clearness the electrical conductors, contacts and other portions of the socket are not shown in the drawings. While various forms and shapes of attaching lugs may be used, and the base block be provided with variously disposed thrust faces to resist forces applied to the lug, the lug and base block are preferably of the shape and form indicated in Fig. 1. Since the two connections there shown are alike, the further description will be confined to one of them.

The base block 1 is provided with a hole 3 extending from the back to the front thereof, and at the side of the central axis 4 of such block. Within the hole 3, and adjacent to the central axis 4, the block is provided with a backwardly facing thrust face 5. A second thrustface 6 acting oppositely to'that ofthe face 5 is formed on the top of the block on the opposite side of the hole 3 from the face 5. Within the hole 3 the lug 7 is placed and may, if desired, be held in position by means of the body of wax 8. The lug shown herein is provided with a laterally or inwardly turned tongue 9 engaging the thrust face 5 with an oppositely projecting portion 10 resting upon the top of a thrust face 6, and with means for engaging an attaching member preferably in the form of an interiorly screw-threaded portion 11 lying in a general plane oblique to the axis 4. The cap 2 is attached to the lug 7 and in turn to the base block I prefer ably by means of a screw 12. By using a lug of the shape shown in Figs. 1 and 3, the tightening of the screw causes the lug to be clamped upon the thrust faces 5 and 6 of the base block, and hence the packing of wax 8 may be omitted without affecting the connection or the manner of making it.

It will be observed of the connection which we have provided that the screwthreaded portion 11 of the lug lies above the top of the base block 1 and adjacent to the cap 2, and that accordingly the screw may be readily caused to engage the lug. A thrust downwardly upon the lug or in the direction 01": the axis of the screw 12 will be resisted by a thrust face 6 of the block 1 and by the wax or packing material 8 between the lug and the wall of the hole 3, the packing material being compressed laterally rather than pushed outwardly. Furthermore, a pull upon the lug will be resisted by the thrust faces 5 and 6 or by the thrust face 5 alone, depending, respectively, upon whether such pull is in the general line of the axis of the screw 12 or in line with the axis of the hole 3'.

I11 case the cap 2 is tapered or of a general bell shape 13 in the plane of the screws 12', the holes 14: through the cap may be directly punched without indenting the metal or otherwise interrupting the continuity of the bell-shaped portion 13. This neatness of construction is made possible by reason of my improved connection wherein the portion 11 of the lug 7 may be disposed at any desired angle to the axis 40f the fitting.

According to the provision of the patent statute, we have described the principle and operation of our invention, together with the construction-which we now consider to be the best embodiment thereof. However, we desire to have it understood that within the scope of the appended claims our invention may be practised with other forms of construction than that shown and described herein.

We claim as our invention:

1. In an electrical fitting, the combination of a base bloch of insulation, a cap inclosing the top thereof, said block being provided with a pair of oppositely acting thrust faces disposed transversely of the central axis of the block and cap, a lug provided with a pair of oppositely disposed bearing faces engaging said thrust faces, and an attaching member extending through said cap and engaging said lug for the attachment of said cap to said block.

2. In an electrical fitting, the combination.

of a base block of insulation, a cap inclosing the top thereof, said block being provided with a hole substantially parallel to the central axis of the block and cap,,and further provided with backwardly facing detent within said hole; a lug provided with a tongue engaging said detent, with a seat resting on the top of said block, and with an interiorly screw-threaded portion lying in a plane oblique to said central axis; and a screw extending through said cap and engaging the screw threaded portion of said lug for the attachment of said cap to said base.

3. In an electrical fitting, the combination of a base block of insulation provided at a side thereof with a pair of oppositely acting thrust faces, a lug secured to said block and engaging said thrust faces thereof, said lug being provided with an interiorly screwthreaded portion projecting above the top of said block, a cap inclosing the top of said block, and a screw extending through said cap and engaging said scr'eW threaded portion of the lug.

4:. In an electrical fitting, the combination of a base block of insulation provided at one side thereof with a hole extending from the top to the bottom of the block and further provided within said hole on the side adjacent to the center of the block with a backwardly facing detent; a lug provided with a laterally extending tongue engaging said detent, with an oppositely extending seat resting on the top of said block, and with an interiorly screw-threaded portion lying in a plane oblique to the central axis of said block; a cap inclosing the top of said block, and a screw extending through said cap and engaging said screw-threaded portion of the lug.

In testimony whereof we have hereunto set our hands.

CECIL It. HUBBARD. DAVID M. COOPER.

Witnesses:

., H. G. KURDREN,

M. EIiBERT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0.

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