US2491463A - Electrical connector fixture - Google Patents

Description

Dec. 13, 1949 w. BROOKS ELECTRICAL CONNECTOR FIXTURE Filed May 4, 1948 INVENTOR.

L/NZY W BROOKS BY ATTORNEYS Patented Dec. 13, 1949 ELECTRICAL CONNECTOR FIXTURE Linzy W. Brooks, Portland, reg., assignor to On-A-Lite Corporation, Portland, Oreg.

Application May 4, 1948, Serial No. 24,941

3 Claims. (Cl. 173-340) This invention relates to an electrical fixture for making connection with a dual conductor electric cord to energize a lamp socket in the fixture.

The invention relates to improvements in the type of connector fixture wherein electrical connection is made with a dual conductor cord by forcing a pair of metal prongs or pins through the insulation of the cord and into contact with the electrical conductors therewithin. The advantages oi this type of connector fixture are that it enables light sockets to be mounted at any point along a conventional dual conductor electrical cord without scraping the insulation from the wires and making a permanent type of connection requiring theuse or tools or solder. Such a fixture is of particular advantage in mounting decorative lights on a conductor cord for lighting a Christmas tree or the like where the lights may have to be placed at irregular intervals on the cord to obtain the desired lighting effect, and wherein it may be desirable to shift the lights to different positions on the cord from time to time, as where the same string of lights is used year after year on different Christmas trees. This type of fixture permits the lights to be moved from one position to another along the cord without leaving parts of the bare conductor wires exposed which would have to be taped, making the cord unsightly and a possible fire and shock hazard if the tape should come 011. and of course involving the work of applying the tape.

In a similar manner, this type of fixture may also be used to energize branch conductor cords from a main cord to add additional strings of lights wherever they may be needed. The lamp sockets on the branch cords may also preferably be of the pin connector type so that they may be spaced at random to give the desired lighting eitect. In addition to the mentioned uses for decorative lighting purposes, this type of fixture may further be used for making temporary or permanent connection with a twin conductor cord for any other purpose whatsoever.

The general object of the present invention is struction having parts which may be easily molded oi-readily available plastic materials, to provide a design for the individual plastic parts which requires less complicated dies for the molding thereot,and to provide an improved form of constructlon and design oi parts to reduce the cost of assembly. Another object is to provide a form of construction for the principal molded parts which will permit the use of the same molding dies to make parts for both a lamp socket type of fixture and extension cord connector type of fixture. Additional and more specific objects of the invention are to provide an improved form of ram or piston element for forcing the wires onto the prongs or pins of the fixture and to provide an improved form of cap member including such piston element.

In the present forms of construction, the principal part or body member may be provided with a screw threaded metallic shell to form a lamp socket or it may constitute a connector fixture for a dual conductor branch or extension cord. The body member has a segmental end portion defining a recess having a transverse channel for the conductor cord with which the fixture is to be connected, and in the bottom of the conductor cord channel are mounted a pair of metallic pins having a length just sufilcient to pierce through the insulation and into the stranded electrical conductors of a conventional rubber or plastic covered twin conductor cord without piercing through the insulation on the opposite side 01' the cord. The conductor cord is forced onto the metallic pins by a ram or piston element which is projected into the said recess. The piston element is carried by a cap member which fits over the segmental end portion of the body member to force the piston toward the pins in the bottom 01' the channel so that electrical connection will be made with the two conductors of the cord in the channel when the cap is secured to the body member. When the body member constitutes a light socket, the cap is provided with a spring clip for mounting the light on a Christmas tree branch or support. The cap may be secured to the body member by a screw threaded connection, or by the use of cooperating projections and recesses.

Other objects and advantages of the invention will become apparent to persons skilled in the art as the description proceeds in connection with the accompanying drawing illustrating preferred embodiments of the invention. It is to be understood, however, that the purpose of the drawing is to illustrate the principles of the invention and not to limit the invention, as various other changes in the form of construction and arrangement of parts will occur to persons skilled in the art, and

all such modifications within the scope ot-the appended claims are included in the invention.

In the drawings:

Figure -1 is a. perspective view of a fixture embodying the features of the invention;

Figure 2 is a sectional view of the fixture shown in Figure 1;

Figure 3 is 'a perspective view oi the fixture shown in Figures 1 and 2, with the cap removed from the body.

The illustrated embodiment comprises a body member 60 and a cap 6|, these two parts having screw threaded interengagement to secure the cap to the body. The body member 60 is provided with a screw threaded metallic shell 39 forming a socket for the lamp 40. The shell 39 has a shoulder 4i mechanically and electrically connected with the riveted end of a sharp pointed prong or pin 25. A resilient center contact 42 for the lamp is mounted on the inner end of a similar pin 26. The body member 60 contains a recess having a cylindrical portion 62 and a, bottom channel portion 63 to receive the twin conductor cord I2. The cylindrical recess 62 is defined by two semicircular wall portions 64 disposed on opposite sides of the conductor cord channel, as shown. The outer cylindrical surfaces of these wall portions are threaded at 65 to engage the threads of the cap 6 l The cap 6| contains an integral cylindrical ram or piston element 66 extending out to the plane of the open end of the cap and of a size to project into the cylindrical recess portion 52 in the body member. The arrangement is such that when the twin conductor cord II or I2 is laid in the channel 63 across the ends of the pins 25 and 26 the cap member may be engaged with the starting threads on the threaded portion 65 to 7 cause the end of the piston element 66, as well as the rim of the cap member, to engage the conductor cord. Then, as the cap is screwed down on the threaded portion 65, the rim of the cap and the end of the piston element 66 force the conductor cord down into its channel 63, causing the pins 25 and 26 to pierce into the cord and make electrical connection with the metallic conductors therein. The electrical as well as the mechanical connection is thereby made, without pressing the wires onto the pins with the fingers, but by merely screwing the cap 6| into place until its rim is seated against the shoulder 61 of the body member. Except for the space between the piston element 66 and the circular rim of the cap, the cap is in engagement with the conductor cord over substantially its whole length within the channel 63 so that the cord will be forced onto the pins effectively, regardless of where the pins are located in the bottom of the channel. It is preferred, however, to space the pins longitudinally in the channel so that they will pierce the cord at spaced points, preferably under the piston element 66. Such arrangement of the pins positively prevents the cord from bending up over the ends of the pins without being pierced, and, at the same time, spaces the two puncture points by a sufilcient distance so that the cord will not be appreciably weakened by the punctures in the insulation.

When the device is made in the form of a socket fixture, a slot or recess 10 is formed in the end of the cap member to secure a mounting clip. In the present embodiment the mounting clip comprises a pair of identical metallic spring members H having projections or barbs l2 raised thereon, as shown, to be snapped into opposite indentations 13 in the walls of the slot or recess Ill. The recess 10 preferably extends up into the piston element 66 to contain enough of the length 4 of the clip element II to provide a firm anchor therefor. The sides of the recess are cut back at 14 to accommodate the spring action of the clip members whereby they may be spread apart to grip a branch or other support close to the fixture. Additional means may be employed to anchor the clip members, if desired, but it is preferred to make the recess 10 of dimensions to frictionally engage the clip members, the plastic material of which the cap is molded being sufficiently resilient in a small cap to retain the projection 12 in the indentations 13 by a snap fit as in a snap fastener.

Still other forms of integral piston elements and other connecting means for securing the cap to the body member utilizing the principles of the present invention will occur to persons skilled in the art.

By mounting the spring clip well within the piston element of the cap member, as shown, the clip members may have suflicient length to provide the desired spring action without causing the fixture to stand high above the branch or other support on which it is mounted. It is desirable to have the fixture mounted as close to its support as possible.

It is to be understood, of course, that the spring clip may be omitted and an extension cord connected directly with the pins 25 and 26 in lieu of the lamp socket 39 to provide an extension cord connector fitting. The various features of novelty in the body and cap members have the same advantage and utility with an extension cord connector fitting as with a lamp socket type of fitting.

In the illustrated embodiment the invention provides a two piece fixture by which additional lamps or extension cords may be connected with a main cord without requiring any tools or the usual skill necessary to make electrical connections. All the elements necessary for making the connection are self-contained in the body member and cap without the use of any screws or nuts which are easily lost and may result in a faulty connection it improperly applied. The threads on the threaded parts are relatively large and easy to engage, and in all embodiments the parts fit in such a manner as to make it self-evident to an unskilled person when they are put together in the proper manner. The pointed pins and electrical connections associated therewith are permanently mounted in an inaccessible position so that a person connecting or disconnecting wires from the fixture cannot possibly come in contact with any energized metallic parts, or with the sharp points. The energized parts are also inaccessible to tin foil and other metallic ornaments used on Christmas trees and the like.

The fixtures may be moved about on the cord as desired from time to time without materially shortening the life of the conductor cord, or all the fixtures may be removed from the cord to make it available for some other use. The single undivided cord channel in each embodiment allows the use of twin conductor cords without splitting the cord around a central bolt as has heretofore generally been necessary in such fixtures.

Having now described my invention and in what manner the same may be used, what I claim as new and desire to protect by Letters Patent is: I

1. An electric light socket fixture comprising a body member, a light bulb socket in one end of said body member, a transverse conductor cord 8 slot in the other end of said body member, said slot havin a narrow bottom portion to tit and confine a conductor cord, contact pins in said bottom portion to pierce said conductor cord and energize said socket, said slot having an up per portion with recessed side walls, a cap having an integral piston element of greater transverse dimension than said narrow bottom portion of the slot, rctative interengaging means on said cap and body member for securing said cap on said body member, said piston element being rotatable in said recesses of the side walls when the cap is applied to the body member, and said piston element having an end surface to hold said conductor cord on said contact pins in said bottom portion of the slot.

2. A portable electric light socket fixture comprising a body member, a light bulb socket in one end of said body member, a single transverse conductor cord slot in the other end or said body member, said slot having a narrow bottom portion with side walls to fit and confine a parallel conductor cord, a shelf within said body member at a distance from the bottom of the slot approximately equal to the thickness of the conductor cord, contact pins extending from the bottom of the slot substantially to the plane of said shelf to pierce the conductor cord and energize said socket, arcuate and parts extending from said shelf and defining an upper portion 01 said slot having recessed side walls, a cap having an integral piston element of greater transverse dimension than the width of said narrow bottom portion of the slot, and means on said cap and body member for securing the cap to the body member with the end or said piston seated against said shelf to hold the conductor cord on said contact pins in said bottom portion of the slot.

3. A portable electric light socket fixture comprising a body member, a lamp socket in one end or said body member, a single transverse conductor cord slot in the other end of said body 6 member, said slot having a narrow bottom portion with side walls to tit and confine a twoconduetor cord, a shoulder around said body member at a distance from the bottom of the slot approximately equal to the thickness of the conductor cord, contact pins extending from the bottom of the slot substantially to the plane of said shoulder to pierce the conductor cord and energize said socket, arcuate end parts extending from said shoulder and defining an upper portion of said slot having recessed side walls, a cap having a rim surrounding said arcuate end parts, an integral piston element in said cap having a greater transverse dimension than the width of said narrow bottom portion of the slot, and rotative interengaging means on said cap and body member for securing the cap to the body member with the rim of the cap seated against said shoulder, said piston element being rotatable in said recesses of the side walls of the slot when the cap is applied to the body member and having an end surface to hold the conductor cord on said contact pins in said bottom portion of the slot.

LINZY W. BROOKS.

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

UNITED STATES PATENTS Number Name Date 1,315,317 Letiecq Sept. 9, 1919 1,542,706 Lang June 16, 1925 1,884,950 Woodring Oct. 25,. 1932 2,440,748 Johnson May 4, 1943 FOREIGN PATENTS Number Country Date 341,265 Great Britain Jan. 15, 1931 412,939 Great Britain July 3, 1934 455,196 Great Britain Oct. 15, 1936

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