US2614190A - Fused electrical connector - Google Patents

Description

Oct. 14, 1952 J. F. CONRAD FUSED ELECTRICAL CONNECTOR Jet Filed Oct. 26, 1950 w r M2 M WM R VC 0 r m w J Patented Oct. 14, 1952 FUSED ELECTRICAL CONNECTOR John F. Conrad, Ebensburg, Pa., assignor to Deltron Electric Products, Inc., Ebensburg, corporation of Pennsylvania Pa., a

Application October 26, 1950, Serial No. 192,259

2 Claims. 1

This invention relates to electrical connectors, and more particularly to connectors of the fused type for use in connection with electrical cables, the device having some features in common with my copending application Serial No. 193,176, filed October 31, 1950.

One object of my invention is to provide a connector of the type which includes a cartridge fuse, wherein the cable ends are more firmly held and more accurately centralized in the fuse holder than in various previously known connectors of this general type.

Another object of my invention is to provide a fused connector wherein the parts within the holder are readily accessible, but are, nevertheless, maintained in assembled position with suflicient firmness to avoid loose electrical connections and consequent faulty conductivity and other damage during handling of the device.

As shown in the accompanying drawing, Figure 1 is a longitudinal sectional view through the connector; Fig. 2 is a view taken on the line II--II of Fig. 1; Fig. 3 shows a modification of the anchoring device for the cable at one of the fuseholding sockets, and Fig. 4 is a sectional view through the structure of Fig. 3.

Referring first to Figs. 1 and 2, the fuse structure is employed to connect ends 6 and l of a sheathed cable. The connector comprises a tubular body member 8 that is of insulating material and suitably may be of a fibrous nature combined with phenolic resin or the like, under high pressure, to give it good mechanical strength.

At one end, a knurled seating member ID suitably of aluminum has tight press fit with the tube 8 and is covered at its outer side by a gasket ll of rubber or other insulating material that is pressed into place. The wire strands of the cable extend through a gland l2 and a collar 13 and are mushroomed or frayed out at M. A fuse socket 15 that is axially split for yieldability, has an outwardly-extended tubular portion [6 with which the gland l2 has threaded engagement. The gland 12, when screwed tightly into place, will cause the collar l3 to clamp the wires against the end wall I! of the extension 16.

In making the assembly, the tube 8 will be slid along the cable end 6, so as to render the bared wires accessible for these coupling members, at the other end of the tube. The wall I! is dished somewhat, so that when the gland I2 is screwed home tightly, the cable will be centralized with respect to the axial line of the bushing II. The parts l2, l3 and I may suitably be of brass.

At its other end, the tube has a knurled bushing 18, suitably of brass, firmly held therein, and there is a cap-like extension 19 of the same material as the tube 8, which has a brass bushing 2| firmly held therein, the two bushings being internally threaded for engagement with a coupling member 22 of brass that has a split socket 23 and an outwardly-extending tubular portion 24 whose end wall is concave. An insulating bushing 25 is snugly held in the outer end of the cap 19.

In assembling the parts, with the coupling 22 removed from the cap 19, the cable end I is threaded through the bushing 25, through a gland 26 and a collar 27 that will centralize the cable end on the concave seat in 22. The cable ends are frayed or mushroomed at 28, and the gland 26 is screwed to clamp the collar 21 against the wires. The cap 19 is then slid along the cable and turned to screw its bushing 2| on to the'extension 24 of the coupling member 22, and the coupling member 22 is screwed into the bushing [8, if it has not previously been screwed into place.

A cartridge fuse 30 of a standard form, having the usual metal caps 31 and 32 engageable in the sockets I5 and 23 respectively, is electrically connected to the end wall of the socket 23 by laminated fiat conductor strips 33 that are riveted at the ends to dies 34 and 35, the rivets preferably being of copper. A spring 36 holds the brass discs 34-35 tightly to their seats and also urges the cartridge into its socket 15 to thereby hold the end of the cap 3| snugly against the bottom wall of the socket l5 and thus provides for better conductivity than that which would be afforded simply by the split sides or fingers of the socket. The spring therefore maintains the electrically conductive parts under pressure and avoids looseness developing during use and handling of the device.

The use of copper rivets for connecting the discs 34-35 to the conductor strips 33 insures better maintenance of electrical connection than is possible with bolts or soldering. Where bolts or screws are used, there is danger of looseness through careless assembly, of occurring during use, while where a solder is used, it has a low melting point as compared to copper or brass and the solder would sometimes soften before or when the fuse reaches a rupturing temperature. Furthermore, copper rivets will usually be employed because of their high conductivity, Whereas in the case of screws, they are commonly made of brass because of better machineability but which is not so conductive as copper.

The laminated conductor strips 33 are advantageous, because not only can they be made of sufiicient length to allow for some extension and retraction, but they provide large total conductive and heat-radiating area and therefore will not develop heat in the confined space to such an extent as to cause the fuse to be ruptured at lower amperage or temperature than that for which the fuse is designed.

A modified form of cable-anchoring device is shown in Figs. 3 and 4. In this case, the gland [2a corresponds somewhat to the gland [2 but is lengthened to provide for a set screw 49 which is turned into the gland to deflector bend thecable, thus holding it more securely than at [4, or subplementing the clamping arrangement at M.

I claim as my invention:

1. An electrical connector comprising a tubular body member of insulating materialhaving an insulating apertured closure member at one end, to receive a cable end, *aconductive eeble-holding de'vice'at the inner side of theclosure member and having a conductive socket to receive one end of afuse cartridge, a threaded bushing rigidly se- "c ured within the body member at its other'end, a tubular cap member of insulating material engageable with said other end of the body member, and having a central hole for a cable, a

threaded bushing rigidly secured within the cap member, a coupling member that is exteriorly threaded for connecting the two bushings and is centrally recessed inits inner' end to serve as a cartridge-receiving socket and having a threaded recess in its outer end, alined with the hole in the cap and an eXteriorly-thre aded gland engage-able with the wall oftherecess to clamp a cable agains't the innerend wall of this recess,

the coupling member and the gland being of conductive material. I V w H 2. Anel'ectrical connector comprising a tubular body member of insulating material having an insulating apertured closure member at one end, to receive a cable end, a conductive cableholding device at the inner side of the closure member and having a conductive socket to receive one end of a fuse cartridge, a threaded bushing rigidly secured within the body member at its other end, a tubular cap member of insulating material engageable with said other end of the body member, and having a central hole for a cable, a threaded bushing rigidly secured within the cap member, a coupling member that is exteriorly threaded for connecting the two bushings and is centrally recessed in its inner end to serve as a cartridge-receiving socket, the recessed portion being of reduced wall thickness and of smaller outside diameter than the threaded portion and being split longitudinally, to serve as a fuse-receiving socket, the outer end of the coupling member being centrally recessed and threaded for engagement with a gland that is centrally apertured 'to receive a'cable that extends through the hole in the cap and clamp the same against the end wall of this recess, the coupling member beingof conductive material.

JOHN F. CONRAD.

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

UNITED STATES PATENTS Number Name Date 1,662,055 Chandler Mar. 13,1928 1,679,142 Wyman July 31, 1928 1,746,650 Harrington Feb. 11, 1930 1,822,883 Chandler; Sept. 15, 1931 2,419,152 'Mosebaoh Apr.-l5, 1947 2,466,997 Morris Apr. 12, 1949 2,475,352 Conrad- July 5, 1949

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