US2622119A

US2622119A - Clampless bottom wiring for electrical devices

Info

Publication number: US2622119A
Application number: US162781A
Authority: US
Inventors: Hubbell Harvey
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-05-18
Filing date: 1950-05-18
Publication date: 1952-12-16
Anticipated expiration: 1969-12-16

Description

Dec. 16; 1952 H. HUBBELL 2,622,119

CLAMPLESS BOTTOM WIRING FOR ELECTRICAL DEVICES Filed May 18, 1950 =mnnm "mm 25 Inventor (F a in W W Gttornegs Patented Dec. 16, 1952 CLAMPLESS BOTTOM WIRING FOR ELECTRICAL DEVICES Harvey Hubbell, Long Hill, Conn.

Application May 18, 1950, Serial No. 162,781

6 Claims.

This invention relates to devices for connecting conductor wires to outlet receptacles, switches and other electrical elements, and an object is to provide an improved wire clamping device adapted for general use with such elements.

Heretofore in connecting lead wires to outlet receptacles, for example, it has been customary for the electrician to bend the stripped end of each wire to form a loop for embracing the binding post screw and then secure the looped end under the head of the screw. Such an operation is not only time consuming, but the resulting connection is not always entirely satisfactory. If the electrician is careless or hurried, the bent loop-may not be properly shaped or sized to be secured correctly under the head of the binding screw, or the wire conductor may be of such heavy gauge that the loop cannot be readily formed. In either case the wire is not engaged and held by the binding screw as securely as is normally required.

A further object is to eliminate this operation by the electrician and to provide an improved device for connecting conductor wires to electric fixtures, switches and the like constructed and arranged to electrically and mechanically connect a conductor wire without requiring any preliminary bending or looping of the stripped conductor.

A further object is to provide an improved device for connecting lead wires to outlet receptacles by back or bottom wiring without clamping the leads around the binding post screws.

A further object is to provide an improved wire clamping device for use with outlet receptacles and the like, so constructed as to provide an efficient electrical connection as well :as a strong mechanical grip merely by inserting the stripped end of a conductor into the device :and' then screwing up on the associated binding With the foregoing and other objects in view,

I have devised the construction illustrated in the accompanying drawing forming a part of this specification. It is, however, to be understood the invention is not limited to the specific details of construction and arrangement shown, but may embody various changes and modifications Within the scope of the invention.

In this drawing:

Fig. 1 is a side elevation of a duplex electrical outlet receptacle having a wire connecting device constructed in accordance with one embodiment of the invention;

Fig. 2 is a part plan, part horizontal section, of one end of the receptacle shown in Fig. 1;

Fig. 3 is a vertical transverse section through the lower portion of the receptacle shown in Figs. 1 and -2;

Fig. 4 is a perspective view showing certain details of the illustrated wire clamp;

Figs. 5, 6 and 7 are views illustrating a detail of the clamping device, and

Fig. 8 is a similar view partly in section of the same detail.

The illustrated embodiment of the invention is shown in connection with an outlet receptacle H, although the invention is equally adapted to other types of electrical devices. As illustrated, the receptacle II is formed of top and bottom sections I2, I3, respectively, of insulating material and a bottom insulating cover plate M. Spring contacts l5 are mounted in chambers [5a in the bottom section l3 to engage the blades of attachment plug caps inserted in the slots H1 in the front wall. The illustrated duplex receptacle includes two sets of such contacts and slots.

Each contact l5 at each end of the receptacle II is connected to a device for securing a conductor lead thereto. As illustrated, a current conducting plate It is provided on each side of the receptacle II and has an inturned flange I! at each end riveted or otherwise connected electrically and mechanically to the corresponding contacts l5 on the same side of the receptacle at each end thereof. Binding screws it are threaded through threaded openings IS in the plate It; and have slotted screw heads 2| positioned in recesses 22 formed in the face 23 of the bottom section l3 of insulating material. Each threaded opening I!) may be re inforced with a threaded collar 24 formed. on or secured to the inner face of they plate 16, if desired.

In order to connect a lead wire to a given contact I5 without any preliminary shaping or bending, plate It has a plate or flange 25 spaced from the plate l6 and connectedto it by a transverse connecting plate 26 bent laterally from this plate at the lower edge thereof. The spaced plates I6 and 25 are in planes substantially parallel to each other, and the plate 25 is so formed as to provide a wire clamping edge 21 on a level slightly below that of the screw opening [9. As shown in Figs. 4 andi'5, the clamping edge 21 is notched,'preferably with a V-shaped notch 28, to adapt it to clamp conductor wires of different gauge, as hereafter explained.

The transverse connecting plate 26 which is shown as located at the back or bottom of the receptacle II has an opening 29 through which the stripped end 3| of a conductor lead or wire 32 can be inserted, the insulating bottom cover l4 having a corresponding opening 33 concentric with the opening 29 for this purpose. Assuming the binding screw I8 is retracted so as not to extend across the axis of the opening 29, when the stripped end 3| of a conductor 32 is inserted through the aligned

openings

29, 33, it will be located opposite the end 34 of the retracted clamping or binding screw It. By then screwing the latter inwardly the end 34 of the screw, which is relatively blunt, engages theside of the stripped end of the conductor and bends the conductor toward the wall 25 of the angle plate and into engagement with the clamping edge 21 thereof, the V-shaped notch 28 accommodating wires of difierent gauge. The threads of the screw bite or cut into the wire to increase the grip on the wire and provide a better electrical connection. In order to prevent the rotation of the screw, as it is threaded into the clamp and engages the wire, from causing the wire to be displaced laterally to the side and thus prevented from being properly bent to engage the V notch, the angle plate 6 is formed with a third or guide wall 35 which is so positioned adjacent the wire as, if necessary, to engage the wire on the side toward which rotation of the screw l8 would tend to displace it, to thereby prevent such displacement and guide the wire into the clamping notch under the advancing movement of the binding screw l8.

In operation, no preliminary looping or shaping of the conductor lead 32 is required, the end 3| thereof merely being stripped of insulation and inserted through the aligned

openings

29, 33 to position it between the blunt end 34 of the retracted screw l8 and the clamping edge 2'1, as indicated in dotted lines Fig. 4. Subsequent screwing in of the screw bends the stripped conductor end 3| into engagement with and clamps it against the edge 21, the V notch 28 accommodating the clamp to difierent diameters of wire.

In the illustrated outlet receptacle II, the two receptacle contacts 25 at an end of the receptacle will be connected to separate wires 32 and 32a, as best shown in Fig. 3, forming the two sides of the circuit. A mounting bridge 33 extends longitudinally of the receptacle H and has ears 39 for securing the receptacle to any suitable supporting surface.

The invention can be variously modified and adapted within the scope of the appended claims.

Having thus set forth the nature of my invention, I claim:

1. An electric fixture having a body of insulating material formed with a recess opening at the back and side of said body, an electric contact in said body, a Wire clamp electrically connected to said contact mounted in said recess and including an angle plate having one wall at the back of said recess and formed with an opening adapted to receive the stripped end of a conductor wire, a second wall at substantially right angles to the first wall and located at one side of said recess, and a third wall substantially parallel to the second wall and located on the opposite side of said opening from this wall so that the opening is located between the second and third walls, said third wall being provided with a wire clamping edge, and a binding screw threaded through said second wall above the first wall to engage one side of the stripped end of a conductor wire projecting into said recess through said opening to bend said wire laterally and clamp it against said clamping edge.

2. An electric fixture having a body of insulating material formed with a recess opening at the back and side of said body, an electric contact in said body, a wire clamp electrically connected to said contact member mounted in said recess and including an angle plate having one wall at the back of said recess and formed with an open- Iing adapted to receive the stripped end of a conductor wire, a second wall at substantially right angles to the first wall and located at one side of said recess, and a third wall at substantially right angles to the first wall and located on the opposite side of the opening from the second wall, said third wall having a wire receiving V-shaped notch in the edge thereof opposite said second wall, and a binding screw threaded through said second wall above the first wall to engage one side of the stripped end of a conductor wire projecting into said recess through said opening to bend said wire laterally and clamp it in engagement with said V-notch.

3. An electric fixture having a body of insulating material formed with a recess opening at the back and side ofsaid body, an electric contact in said body, a wire clamp electrically connected to said contact member mounted in said recess and including an angle plate having one wall at the back of said recess and .formed with an opening adapted to receive the stripped end of a conductor wire, a second wall at substantially right angles to the first wall and located at one side of said recess, and a third wall forming a wire clamping edge, located at the opposite side of said opening from the second wall, a binding screw threaded through said second Wall above the first wall to engage one side of the stripped end of a conductor wire projecting into said recess through said opening to bend said wire in a direction longitudinally of the screw and clamp it against said clamping edge, and a guide wall located at one side of the screw to prevent lateral displacement of said Wire when engaged by said screw whereby to guide the bent end of said wire against said clamping edge.

4. An electric fixture having a body of insulating material formed with a recess opening at the back and side of said body, an electric contact in said body, a wire clamp electrically connected to said contact member mounted in said recess and including an angle plate having one wall at the back of said recess and formed with an opening adapted to receive the stripped end of a conductor wire, a second wall extending at an angle to the first wall and located at one side of said recess, and a third wall formed with a wire clamping edge located at the opposite side of said opening from the second wall, and a binding screw threaded through said second wall above the first wall to engage one side of the stripped end of a conductor wire projecting into said recess through said opening to bend said wire in a direction longitudinally of the screw and clamp it against said clamping edge, and a guard member located at one side of the screw for guiding the stripped end of said wire into engagement with said clamping edge as it is bent by operation of said screw.

5. The combination in an electrical device having an electrical contact, of means for connecting a wire to said contact comprising spaced substantially parallel plates electrically connected to said contact, one of said plates having a clamping edge, means for positioning a conductor wire between said plates with its axis substantially parallel to the planes of said plates comprising a third plate extendin between and connecting the first two plates and provided with an opening for the conductor wire leading to the space between said plates, and a clamping screw threaded through the second of said plates into said space for movement transverse to said wire to engage one side of and bend said wire toward said clamping edge and clamp the bent portion against said edge.

6. The combination in an electrical device having an electrical contact, of means for connecting a wire to said contact comprising spaced substantially parallel plates electrically connected to said contact, one of said plates having a clamping edge positioned substantially opposite a threaded opening in the other plate, a third plate extending between and connecting the first plates provided with an opening leading to the space HARVEY HUBBELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,830,466 Hines Nov. 3, 1931 FOREIGN PATENTS Number Country Date 734,046 France July 25, 1932