US2795677A

US2795677A - Electrical wiring device

Info

Publication number: US2795677A
Application number: US507811A
Authority: US
Inventors: Saul I Slater
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-05-12
Filing date: 1955-05-12
Publication date: 1957-06-11
Anticipated expiration: 1974-06-11

Description

June 11, 1957 s. l. SLATER 2,795,677

ELECTRICAL WIRING 'DEVICE Filed May 12, 1955 2 Shets-Sheet 1 INVENTOR. 4 5 404 f 51/175,?

'I I. I I ganfifo ELECTRICAL WIRING DEVICE Filed May 12, 1955 2 Sheets-Sheet 2 50 50 45 In I 48 1 T4 70 4 7 4/ 4/ I INVENTOR. F f 1 5,404 51/175? 6 4,3 4/ f 4 I 48 8 BY 09 o9 United States Patfifit i ELECTRICAL WIRING DEVICE Saul I. Slater, Forest Hills, N. Y.

Application May 12, 1955, Serial No. 507,811

3 Claims. (Cl. 200-166) The present invention relates to electrical wiring devices and particularly to a switch or outlet of the type commonly used in building construction which is provided with terminals for the wire leads which grip the stripped wire ends and release them only upon pressure upon the gripping members. Although the invention is useful in plug receptacles, it is shown particularly in the accompanying drawings as embodied in a switch construction wherein the other portions of the switch are specifically designed for use with grip type terminals such' as are mentioned briefly above.

In the usual electrical wiring installation, outlet boxes are provided in walls and metallic cable of the type usually known as BX is fastened to the outlet boxes through the use of apertures in the boxes and BX connectors at the ends of the cable. In such installations a maximum amount of wire lead-in is in the neighborhood of 4 to inches since more wire cannot be accommodated in the outlet box together with the switch or plug outlet. Consequently the wires must be connected to the switch or outlet or other wiring device while that device is held close to the wall surface, and additionally, at any time when the wiring device is to be replaced or wiring modified it is necessary to disconnect the wire from the terminals while the wiring device is held immedately adjacent to the plane of the wall.

The present invention provides a wiring device so arranged that a common screwdriver may be utilized to press against the wire gripping members to thereby release the wires from the terminals making it possible to readily replace the wiring device without the use of special tools such as short and narrow bladed screwdrivers which-must be used for wiring devices having gripping terminals such as are currently in use.

It isan object of the invention to provide a wiring device having wire gripping terminals, the terminals and housing being ,so arranged that the gripping members may readily be released with the use of the ordinary tools, thus obviating the use of special tools such as short and narrow bladed screwdrivers and the like;

It is another object of the invention to provide a switch structure having wire gripping terminals as described above and in which the other elements of the switch are peculiarly adapted for use with these wire gripping terminals. I

It is a further object of the inventionto provide a switch Figure 4 is an enlarged cross-sectional view of the switch of the present invention, the view being taken on the plane of the line 4-4 of Figure 3;

Figure 5 is a view similar to Figure 4, the view however being taken on the plane of the line 5-5 of Figure 3;'

Figure 6 is another cross-sectional view, this view being taken at right angles to the cross-sections of Figures 4 and 5 and specifically on the plane of the line 6-6 of Figure 5;

Figure 7 is a vertical cross-sectional view taken on the plane of the line 7-7 of Figures 3 and 6;

Figure 8 is a horizontal cross-sectional view, the view being taken on the plane of the line 8-8 of Figure 7;

Figure 9 is an enlarged perspective view of the operating handle of the switch of the instant invention; and

Figure 10 is an enlarged view, in perspective, of a cross-over member which may in some instances be utilized in order to simplify the wiring installation.

Referring now to the drawings, the switch comprises a housing 10 which may be molded of electrically insulating material, this housing being assembled with an operating handle 11 and a plate 12 which holds the handle 11 in place and which is clamped to the housing 10 by means of the ears 13 bent over molded projections 14 of the housing body 10.

As shown in Figure 1 the switch has been removed from an outlet box which is flush with the wall 15 preparatory to releasing the conductors 16 and 16a from the terminals. In order to accomplish this a screwdriver, such as is indicated in dot-dash lines at 17, is placed in one of the slots 52 in the housing 10 and pressed toward the front to release the wire gripping members in a manner which will be described hereinafter.

Referring now to Figures 4 through 8, it will be seen that the body '10 is provided with a plurality of internal projections and depressions which serve to support the various wire terminals and switch elements in their proper positions. Additionally, a cover plate 12, which is usually metallic, fits over a rim 20 on a cover member 21 and serves to hold that cover member in position against an internal shoulder 22 on the housing 10. Cover member 21 is provided with semi-circular cutouts such as indicated at 23 in Figure 6, which cutouts cooperate with the handle member 11 to hold it in position but capable of oscillation.

The handle member 11, as is seen in Figure 4, comprises a shaft portion 24 which, as explained above,

rotates in the. semicylindrical cutouts 23 of the cover member 21 and in cooperating depressions 24a in the internal wall of the housing 10. The shaft-like portion 24 of the handle 11 carries, in addition totheserriicylindrical portions mentioned, cam surfaces at 25, 26 and 27, the handle being, molded to shape from electrically insulating material. Bearing against the surface 26 is an L-shaped resilient detenting member 26a which member is supported in a T-shaped slot 28, extending vertically in the body portion 10. This member 26a thus serves to retain the handle 11 in either of .two positions, as is clearly seen in Figure 6, it being understood that the surface 26, although mentioned as being a cam surface, is actually a circle are so that the retention of the handlein its selected position is achieved purelyby the frictional engagement between the. end ofthe spring or resilient member 26a and the surface 26. Y i

I Mounted in the T-shaped' slot I 30 formed in the body Patented-June 11, 1957" is a second L-shaped metallic member 31 which is formed at its lower end with a rounded portion 32 adapted to conform to the semicylindrical surface of a conductor such as 16 from which the insulation has been strippedr The member 'is held in position by engagement of its upper bent-over ends with the underside of the cover member 21. as is clearly seen in Figure 5.

Fastened to the member 31 by "any suitable means such, for example, as a rivet 33, is a resilient member 34 bearing a contact 35 at its outer end, the contact 35 being preferably of a highly conductive material such as silver. The member 341 is engaged by the cam surface 27 formed on the handled and thus, as the handle is oscillated, the member 34 flexes, causing the outer end thereof including contact 35 to move upwardly and downwardly as seen inFigure 5.

Mounted in slots 36 in the body It! is an L-shaped member 3'7 similar to the member 36, this member being formed with a rounded portion 38 which engages another conductor such as the conductor 16a. The member 37 is held in position by the cover member 21 due to the fact that the lower surface of member 21 bears against the upper bent-over horizontal portion of the.

member 37. Member 37 carries at its upper end a contact 40 which is in vertical alignment with the contact 35 of member 34, this contact 4-0 being also preferably of silver. Thus, when the handle 11 is oscillated to its left hand position as seen in Figures 4 and 5, a circuit is completed from conductor 16 through member 37, contact 4%, contact 35 and member 34 to conductor 16a,

and when the switch handle is moved to its right hand position member 34 is depressed and the circuit broken at contacts 35 and 40.

, A spring member 41 of generally U-shape is positioned in the slots 42 in the body portion 12 which slots extend forwardly from the rear portion43 of the housing'lh. The member 41 has the base portion thereof lying against the rear portion 43 of the housing and has the terminal portion id extending across the aperture in the rear of housing 1% through which aperture the conductor 16 passes. The terminal 44 of member 41 has a sharp edge which, when a wire such as 16 is inserted through the aperture 45 (as shown in Figure 5), bears against that wire and prevents removal thereof. It will be noted that the member 41 has a bend 46 therein adjacent the opposite end which causes the memberto exert a considerable resilient force against a conductor such as 16 when positioned as described.

The member 41, which has thus far been described, is in the left hand portion of the housing as seen in Figure .5 and cooperates with the conductor 16. An

the body member 10 is provided with slots 52 adiacent the apertures 45 and further that the slots 52 are in alignment with the terminal ends 44 of the members 41. Additionally, the slots 52 extend from approximately the center line of aperture 45 to the edge of the housing and thence forwardly in the side wall of the housing. Slots 52 are wide enough so that the blade of the usual screwdriver customarily'carr'iedby electrical installers may be insertedtherein. Thus, as is seen in Figure l, a screwdriver such as '17 may be inserted in one of the slots 52 and when pressed forwardly will press the terminal end 44 of the, corresponding member 41 forwardly moving the edge thereof forwardly and out of engagement with the corresponding conductor such as 16, thus freeing the conductor for removal from the corresponding terminal 31 and permitting it to be removed through the aperture 45.

Since wiring'devices such as switches and plug re ceptacles are fastened imposition by means of screws which extend through the mounting plate 12 and are threaded into gears on the outlet box, it is necessary that the installer carry a screwdriver at all times, but this screwdriver is relatively large and cannot be utilized when the slots 52 extend only from adjacent the center of the apertures '45 to a point near the side wall of the housing body it). Moreover, when the slots 52 are formed in the rear wall only it is necessary to insert the screwdriver blade from the rear and frequently the wiring device caunotbe removed sufliciently far from the wall to permit the insertion of a screwdriver having a normal length blade and handle. Consequently, the installer is compelled to carry a special tool or at best a short, narrow bladed screwdriver which can be utilized for releasing wires from the terminal members of the wiring device.

' As will be seen, by extending the slots 52 to the side wall and forwardly, no special tool is necessary to release the circuit conductors from the switch terminals and therefore the wiring device of this invention is of great practical advantage.

While I have described a preferred embodiment of the invention, it will be understood thatI wish to be limited not by the foregoing description, but solely by i the claims granted to me.

exactly similar member 41 is positioned in the right hand 5 Moreover, the two members 41, which tioned in the forward portion of the housing as seen in Figure 8, these members cooperating with conductors in the same manner as do the first described members 41. However, in the particular embodiment shown, a means is provided for making a connection through the housing body 10 so that the other side of the circuit which has no switch therein can be more readily wired since no splice is necessary but instead the connection may be made by simply inserting the two wire ends in apertures 45 in the housing. This is accomplished by means of a cross-over member 47 which is of U-shaped form as seen particularly in Figure 10, the ends of the arms of the U being rounded as indicated at 48 to cooperate with the conductors and there being extensions 50 on each end of the member 47 which extensions are bent over sothat the cover member 21 holds the member 47 in place in the slots 51.

Referring now to Figures 2 and 3, it will be seen that What is claimed is: 1. An electrical wiring device comprising, in combination, a hollow body of electrically insulating material forming a housing, said housing having at least rear, end and side wall portions, a wire engaging member extending forwardly from said rear Wall, an aperture in said rear wall adjacent said wire engaging'member, a wiregripping member extending across at least a portion of said aperture, said gripping member being resilient and inclining from the'rear toward the front whereby said member serves to press a wire extending through saidaperture againstv said engaging member, and a slot extending from a point adjacent the center line of said aperture on the side opposite said wire engaging member to the adjacent side wall and forwardly insaid side wall, said slot providing ingress for a tool through said side and. rear walls for pressing said gripping member forwardly to thereby release a wire held between said engaging and gripping members. 7

2. An electrical wiring device comprising, in combination, a hollow body of electrically insulating material forming a housing, said housing having at least rear, end and side wall portions, an aperture in said rear wall, a

. wire gripping member with an edge extending across at vided for a tool through said side and rear walls for pressing said gripping member forward to release a wire retained by the device.

3. An electrical wiring device, comprising in combination, a hollow body of electrically insulating material forming a housing, said housing having at least rear, end and side wall portions, a wire engaging member within said housing, an aperture in said rear wall adjacent said wire engaging member, a wire gripping member with an edge extending across at least a portion of said aperture, said edge being resiliently supported with respect to said housing whereby said member serves to press a wire extending through said aperture against said engaging member, a slot in said rear wall, the forward projection of which intercepts a portion of said gripping member, said slot extending to the end of the rear wall and forward in the side wall to a point forward of the gripping member whereby ingress is provided for a tool through said side and rear walls for pressing said gripping member forward to release a Wire retained by the device.

References Cited in the file of this patent UNITED STATES PATENTS 2,644,144 Richardson June 30, 1953 2,705,787 Benander Apr. 5, 1955 2,708,225 Fitzgerald May 10, 1955 2,720,634 Hart Oct. 11, 1955 FOREIGN PATENTS 726,317 Great Britain Mar. 16, 1955