US2459032A - Electrical connector - Google Patents

Description

JUL 11 1949. L w. J. KoRTH 2,459,032

ELEc'rnIcAL CONNECTOR Fuga opt. 5, 1946 (h. l d'.

F1 ,3 j INVENTOR.

ATTORNEYS Patented Jan. 1l, 1949 ELECTRICAL CONNECTOR William J. Koi-th, Cleveland, Ohio, assignor of one-half to Sam W. Levine, Cleveland, Ohio Application October 3, l1946, Serial No. 700,848

2 Claims. l

This invention relates to a multipart electrical connecting device in which the parts may be rotated with respect to each other so that a cord attached to oneof them will not twist or kink. More particularly the invention relates to such electrical connectors in which connection is made between a household appliance cord and the receptacle of an appliance or source ofcurrent.

Devices of the type indicated above have been made with the object of eliminating any twisting or kinking of an electrical cord attached to them as when one end of the cord is rotated or twisted and the other is not. Such devices have been made in the form of a multipart connector in which two parts mounted on the same central axis could be rotated relative to each other and yet maintain the required number of electrical connections between the two parts. The prior known devices for accomplishing this result have been subject to numerous disadvantages. Some of these disadvantages arose out of the cost of manufacture, as well as the safety and reliability, of such prior devices.

For the uses contemplated, particularly household uses, a low priced item is essential. On the other hand for the same purposes, and particularly to secure approval of the underwriting laboratories, the devices must be safe under all reasonable conditions of use and also durable in construction.

The general object of this invention is to provide an improved electrical connector of the type indicated in which two parts may rotate freely with respect to each other while maintaining a plurality of electrical connections from the one to the other. Another object of the invention is to provide such a multipart connector to which electrical connection may be made in various ways .as by a 'cord or a pronged socket. Still another object of the invention is to provide such a connector to one part of which an electric cable may be secured and that part rotated freely with respect to another part of the device that is electrically connected to it. Still another object is to provide an economical, safe and dependable type' of multipart connector that may be made economically for household use and related purposes.

These and other objects will more fully appear from the following description of my invention, the essential features of which are summarized in the claims, reference being had to the accompanying figures in which:

Figure l is an exploded view of one form ofvmy invention;

Figure 2 is a longitudinal section through the axis of rotation of the central connector of Figure 1, and;

Figure 3 is a longitudinal section of another form of connector that embodies my invention.

Referring now to the drawings my invention is shown as directed to an electrical connector with two parts rotatable relative to each other for linking the end connectors of one or more cords so that they will not become twisted or kinked upon such rotation. The invention is equally adapted to use with plugs or sockets and similar power outlets which require direct and permanent connection with a cord, as shown particularly in Figure 3. While those forms of the invention illustrated herein represent preforred embodiments thereof it will be understood that modifications may be made without departing from its scope and that the invention is limited only by the appended claims.

Essentially the connector in either form comprises a pair of shell-like housing parts that are freely rotatable with respect to each other about a common axis. A set of vcooperating terminals are carried by each part and interengage to maintain electrical contact between them and leads connected to the parts for every angular position of the parts, thus permitting an uninterrupted flow of electrical current irrespective of the adjusted position of the parts.

As illustrated in Figure 1 acord I to be connected to a source of power, is provided with a p female socket plug 3 at one end that is connected by an intermediate multipart Connector. made in accord with this invention, to a cord 2 leading to any desired power consumption unit and having a male plug 4. The multipart intermediate connector is generally indicated at 5 and,

according to my invention, is adapted to engage.

plugs 3 and 4 and electrically connect cords I and 2 so that they may be turned relative to each otherv without twisting or kinking.

The connector 5, as illustrated in detail in Figure 2, comprises a pair of substantially circular cylindrical shell-like housing parts 6 andl and part I define an annular groove I3 in which the flange I0 of shell part 6 is loosely confined, thereby effectively prohibiting any appreciable longitudinal movement of parts 6 and I away from each other along their common axis of rotation but at the same time enabling relative rotation between them. An internally threaded portion I I of the sleeve 8 engages\with external threads I2 of the part 'I to hold the shells together as shown.

In order to maintain an uninterrupted dow of current across the parts of the connector and yet p .rmit rotation between them when desired, the parts are provided Vat opposite ends -with approprate and interconnected terminals for engaging plugs 3 and 4. These terminals are connected by a pair of floating contacts which bridge the rotr able connection and maintain electrical contact in every angular position.

To maintain contact with a male plug 4 a pair of terminals I4 and I5 is mounted in shell 5 on a cross-piece I6 of Bakelite or similar material which spans the mouth of the part and is secured thereto by screws I1. `The interior of part is provided with two opposed radially extending longitudinal ribs I8 which are notched as at I9 in order to mate with the notched ends of cross-piece I5 and Provide a rm and snug seat therefor. The screws I1 extend upwardly through the cross-piece into the ribs as shown. The terminals |4 and |5 are L-shaped metal strips whose upright portions are positioned to make contact with the prongsof plug 4 which extend inwardly through apertures 2| when the connector is in use. The upper ends of each terminal may be bent slightly outwardly as at 22 and 23 to facilitate initial contact with the prongs of the plug 4 when they are inserted within the connector.

Suitable contacts link the terminals 4 and I5 to prongs mounted in member 1 to connect with the female plug 3 in order that the ow of current will be maintained between shell members 6 and 1 and plugs 3 and 4 consequent upon their relative rotation. Terminal 24 is preferably a flat annular ring of brass or other conducting metal iixedly seated in a corresponding annular groove 24a in the bottom wall 26 of the interior of member 1. A prong 21 is formed integrally with the ring and extends through the bottom wall of the connector. Terminal 25 is formed by a flat rectangular plate, preferably of brass, which is mounted in the bottom of a central cylindrical recess 29 in the bottom wall 25. A prong 28 is integrally connected to terminal 25. The prongs 21 and 28 cooperate to make electrical connection with a mating female plug or socket that is equipped with prongs similar to those illustrated at 22 and 23.

At the time member 1 is molded from Bakelite or other similar insulating material provision is made for the insertion and retention of terminals 24 and 25. The circular groove 24a is formed in the bottom wall of member 1 so as to receive the ring in press fit, and a longitudinal groove receives the prong 21 which extends through the bottom wall 25. The recess 29 is formed in the central portion of the bottom wail so that terminal 25 will lie in a lower plane as shown in Figure 2 than terminal 24 and hence be relatively isolated. This aiords to the plug a greater degree of safety if a part becomes broken because it materially prevents such broken part from shorting across terminals 24 and 25. A recess 25a and a longitudinal groove 28a are molded in shell 1 to receive terminal 25 in press fit and permit insertion of prong 28. On assembly a Bakelite plug 30 overlies the recess 25a to retain the terminal 25 securely locked in place. If desired as an alternative method of assembly, terminals 24 and 25 and prongs 21 and 28 may be secured within member 1 at the time it is molded under heat and pressure. k

In order electrically to connect the two sets of terminals for engagement during 360 of relative movement between members 6 and 1 I provide conducting pin members 3| and 32 bridging terminals I4 `and 25 and I5 'and 24 respectively. The member 3| comprises a relatively long slender metal pin connected at its upper end to terminal |4 by a ilexible connection 33. The pin .passes freely through a hollow rivetl 35, which holds terminal I4 to cross-piece I6, and extends into the recess 29 to contact the exposed face of terminal 25 carried by the shell 1. The axis of pin 3| preferably coincides with the central axis of the connector and the pin has a slightly rounded and enlarged head 34 to engage terminal 25 against which it is continuously urged by a coil spring 36 surrounding it and interposed between the cross-piece I6 and head 34.

Pin member 32, in all respects similar to pin 3|, but shorter, is connected to terminal I5 by a exible lead 31 and extends through and slides freely within the hollow rivet 35 which holds terminal I5 to cross-piece I6. This pin member makes contact with the ring terminal 24 by reason of a coil spring 38 which is interposed between the cross-pieceand an enlarged head 39 of the pin.

It is this described arrangement which enables the connector to function in the desired manner. Assuming that part 6 is rotated with respect to part 1, pins 3| and 32 will be carried along by the crosspiece I5 and, being permanently connected with terminals I4 and I5, will transmit current by maintaining wiping contact with terminals 24 and 25 respectively. The pin 3| and terminal 25 rotate with respect to each other about the axis of rotation of shell members Ii4 and 1 meanwhile continuously making electrical connection. At the same time pin 32 traces out a circular path over terminal 24 maintaining elecanother or to a ground position with respect to which the connector may be located. In the present construction this is attained by a combination of means including the location of the terminal ring 24 and the terminal 25 in different planes transverse to the axis of rotation of the shell members 6 and 1. This reduces any likelihood of shorting between the parts such as might occur if the terminals were positioned with their exposed surfaces in the same plane transverse to the said axis of rotation.

The safety aiorded by this construction is supplemented by provision of a sleeve 43 that loosely surrounds the spring 36 and its associated pin member 3|. The sleeve is somewhat shorter than the normal axial distance between the opposed faces of the terminal 25 and the cross member I6. It is constructed of insulating material to act as an electrical insulator interposed between the groups of elements making electrical connection through the pins 3| and 32 respectively. Also, if any parts of the pin 3| or the spring 36 should break, they will be retained within the sleeve 40 and thus will be prevented from shorting across to those other contact elements cooperating with pin 32.

In order to assemble the connector, the contacts 3| and 32, with the associated sleeve 4|! and springs 36 and 38 are connected to the part 5 by inserting the ends of the contacts through ananas the respective hollow rivets extending through cross-piece I6 and wiring them to terminals I4 and I5 respectively. The cross-piece I6 is then fastened to part 6-by the screws I1. Parts 6 and 'I are positioned adjacent each other with their open ends abutting and external threaded sleeve 8 is screwed down until the parts 6 and 1 are brought together. In this position contact II bears against the central portion of terminal 25 and contact 32 rides on the ring 24 due to the force of the coil springs 36 and 38 respectively.

My invention is illustrated in another form in Figure 3 that is adapted to be attached directly and permanently to an electric cord. In this particular form the connector or plug does not differ from that illustrated in Figure 1 in principle but only with respect to part 6 and its associated terminals I4 and I5. In the form of Figure 3 the part 6 is replaced by a substantially cylindrical cap 42 having a flange 4I which cooperates With part 'I and sleeve .8 in the same manner as previously described for part 6 and flange I0.

A cord 41 is passed through the opening 43 of cap `42 and the separate leads 48 and 49 oi' the cord are attached to the conventional screw terminals 45 and 46 respectively. The terminals 45 and 46 are preferably mounted on internally threaded hollow rivets 5D and 5I respectively, extending through the cross-piece I 6 and each comprises a washer and a bolt threaded into the rivets from the bottom side of the cross-piece. Pin contacts 3I and 32 -extend upwardly through hollow rivets as described above with regard to the connector of Figure 2 and are connected to the terminals by wires 33 and 31 in the same manner.

The form of the invention illustrated in Figure 3 is assembled in the same manner as described in connection with the form of Figure 2 and operates in the same way. As the cap 42 and the shell 1 rotate with respect to each other as permitted by the sleeve 8, electrical connecv tion is continuously maintained between the leads 48 and 49 of the cord 41 and the prongs 21 and 28. This is accomplished as heretofore explained by the connection made through pins 3| and 32 with the terminals 25 and 24 respectively.

From the foregoing description it will be seen that my present invention embodies a multipart electrical connector that may take several different forms and that effectively prevents any twisting or kinking, due to rotation of the parts, of a cable or cables connected to it. Thus a cable or device connected to one part of the multipart connector may be held stationary while another and electrically connected part of the connector is rotated to facilitate engagement with either another cord or cable or another elec trical device.

As indicated above various modifications may be made in the present invention without departing from the scope thereof and it is to be understood that I consider such modifications to form part of the present invention, such invention being limited only by the appended claims.

I claim:

1. In a device of the character described, two hollow molded dielectric shell members adapted to be mounted with their hollow portions opening toward each other and detachably joined together for relative rotation about a common axis, a cross member secured to one of said shell members, contacts carried by said cross member on the inner face thereof to make electrical connection with the prongs of a male plug connecting device entering into said one hollow shell. two guideways formed in said cross member, one extending along the axis of rotation of said shell members and the other parallel thereto, vpins slidably carried in each of said guideways,` electrical connections between each of said pins and through said contacts to each of said prongs respectively, a shield of insulating material enclosing substantially the whole free length of the axially extending pin, a terminal in one plane of said other shell and in alignment with said axially mounted pin, an annular terminal ring mounted in another plane of said other shell spaced from said first plane and adapted to encircle said axially mounted pin, coil springs encircling each of said pins and bearing at one end against said cross member and at the other end against said pins to urge said axially mounted pin into electrical contact with said terminal and said other pin into electrical contact with said terminal ring, and electrical connector prongs integral with said terminal and terminal ring respectively and passing through said other shell to the exterior thereof for engagement with a female plug socket.

2. In a device of the character described, two hollow molded dielectric shell members adapted to be mounted with their hollow portions opening toward each other and detachably joined together for relative rotation about a common axis, a cross member secured to one of said shell members, contacts carried by said cross member on the inner face thereof to make electrical connection with the prongs of a male plug connecting device entering into said one hollow shell, two guideways formed in said cross member, one extending along the axis of rotation of said shell members and the other parallel thereto, pins slidably carried in each of said guideways, electrical connections between each of said pins and through said contacts to each of said prongs respectively, a relatively deep cylindrical recess located axially in said other shell and a terminal in the bottom of said recess, and an annular terminal ring mounted in said other shell in a plane above said recess and adapted to encircle said recess and said axially mounted pin, coil springs encircling each of said pins and bearing at one end against said cross member and at the other end against said pins to urge said axially mounted pin into electrical contact 'with said terminal and said other pin into electrical contact with said terminal ring respectively, a sleeve of insulating material enclosing substantially the whole free length of said axially extending pin and associated coil spring and electrical connector prongs integral with said terminal and terminal ring respectively and passing through said other shell to the exterior thereof for engagement with a female plug socket.

WILLIAM J. KORTH.

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

UNITED STATES PATENTS Date.

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