US2478082A - Electrical connector - Google Patents

Description

Patented Aug. 2, 1949 y 2,478,082 ELECTRICAL CONNECTOR William F. Broske, Harrisburg, Pa., assignor to Aircraft-Marine Products, Inc., Harrisburg, Pa., a corporation of New Jersey Application October 24, 1945, Serial No. 624,148

1 claim. l

This invention relates to electrical connectors.

Although applicable to various types of connectors, it will be described as it may be embodied in a connector of the straight-through type.V

The described embodiment is of the class which is intended to be attached between electrical conductors without soldering.

There are many instances Where the ends of two wires require joining together. Sometimes the joining should be such that the two ends can be readily separated, and sometimes the two wires must be permanently bonded to one another. In the case where the bond is tobe permanent the connection must be one involving minimum resistance to current flow and maximum length of life. If the bond is to occur in the circuit oi a sensitive electronic device where low currents and voltages are present, whatever resistance to current flow does accompany the connection must remain absolutely constant at all times. In order to maintain a high-grade mechanical and electrical bond it has heretofore been discovered that the bond should be protected against the entrance of moisture and other foreign matter. The present invention has particular utility in making possible a bond which is sealed against moisture and in which an inspection of the completed connections is possible to make sure that the crimping operations have been properly performed.

In part the invention is an improvement upon the invention described and claimed in the patent to William S. Watts, No. 2,410,321, relating to a preinsulated terminal. Essentially a preinsulated terminal includes a tough plastic insulating sheath which extends over and protects the metal ferrule portions of the terminal. These plastic sheaths are sufficiently tough that the metal of the electrical connector can be crimped in the ordinary manner onto the metal wire, using pressures which cause a cold metal flow and resulting weld to occur between the connector and conductor surfaces, without cutting or injuring the plastic sheaths. As will be apparent, the present invention may be incorporated in preinsulated terminal constructions other than that of the straight-through connector shown herein.

It is an object oi' my invention to provide an electrical connector of the character described having to a notable extent the characteristics and lcapabilities above set forth. A further object resides in the provision of connector means wherein the connection is more available for visual inspection upon completion than has heretofore been the case. The invention has as a further object the provision of either a straight-through or single-ended electrical connector of the preinsulated type wherein visual inspection of the location of the end of a stripped wire is possible both before and after the crimping is completed. A further object is the provision of an electrical connector of the preinsulated type wherein the stripped end of the electrical conductor remains visible for inspection but at the same time is sealed against the entrance of moisture and other corrosive material. Other objects will be in part pointed out as the description proceeds and will in part become apparent therefrom.

In this specification and the accompanying drawings, I have shown and described a preferred embodiment of my invention and suggested various modifications thereof; but it is to be understood that these are not intended to be exhaustive nor limiting of the invention, but, on the contrary, are given for purposes of illustration in order that others skilled in the art may fully understand the invention and the principles thereof and the manner of applying it in practical use so that they may modify and adapt it in various forms, each as may be best suited to the conditions of a particular use.

In the drawings:

Figure l is a plan view of an electrical connector embodying the invention, engaged between a pair of electrical conductors to be bonded together;

Figure 2 is a sectional view of the connector shown in Figure 1 taken along the line 2 2;

Figure 3 is a perspective view of an inner connector contact piece; and

Figure 4 is a perspective view of an insulation supporting sleeve.

In Figure 1 an electrical connector embodying the invention is generally indicated by the numeral 20. It includes an inner connector piece 22 (see also Figure 3) made of a highly conductive metal such as pure copper and it has an insulation supporting sleeve 24, 26 teleseoped over each of its ends. One of these sleeves is illustrated in Figure 4. It is of the general type disclosed in the patent to Buchanan No. 2,379,567; ordinarily the sleeve is seamless and is made of metal. An outer sheath 28 of tough plastic material embraces the assembly of contact piece 22 with sleeves 24 and 26 and, as illustrated in Figures 1 and 2, projects beyond each end thereof. Connector contact piece 22 is formed with ferrule portions 30 and 32 at each end and an intermediate bridging portion 33 extending integrally therebetween. The outer sheath 28 is made of a 'C lfnsparent material such as transparent Vinyl- 3 ite, polybutene, etc., and, accordingly. a windowiike portion 34 overlies bridging portion 33 and forms, together with the ferrule portions, a clearance region indicated at 36. l

As shown in Figure 1, a pair of Wires 38 and 40 to be permanently connected together may have their stripped wire ends 42 and 44, respectively, inserted into the connector. The transparent portion 34 makes possible a visual examination of the positions of ends 42 and 44 within clearance region 36, thus giving ready assurance that if the connector ferrule portions are now crimped a good contact can be made with each of the wires.

Any failure to insert a suilicient stripped wire length in the connector ferrule is immediately obvious and may at once be corrected, or, if not corrected, may easily be discovered upon a subsequent inspection. In use in the field, sheath 28 protects the crimp against the entrance of moisture and at all times makes possible a visual check of conditions within region 36.

The supporting sleeves 24 and 26 and/or the ends of the sheath 28 may be sealed to the insulation of the wires by the use of an appropriate die. One such die is described and claimed in Carlson Patent No. 2,359,083. Sheath 28 is tightly sealed to the outer peripheral surfaces o f sleeves 24 and 26. If the sleeves are omitted the sheath is sealed to the exterior surfaces of ferrule portions 30 and 32. If the sleeves and/or projecting ends of sheath 28 are now sealed to the insulated wire, the entire inner crimp is protected against corrosion.

From the foregoing it will be seen that an electrical connector made in accordance with the present invention is well adapted to attain the ends and objects hereinbefore set forth and to be economically manufactured since the Whole combination is suited to common production methods and is susceptible to a wide latitude of variations as may be desirable in adapting the invention to diierent applications.

As various embodiments may be made of the above invention and as changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

A straight through connector comprising highly conductive cylindrical sleeve members coaxially and integrally joined by a bridging member defining with the adjacent ends of said sleeve members an aperture affording visual access to the axis of the sleeves between their adjacent ends, a sleeve for supporting the insulated port1on of a wire entering the respective sleeve members, said sleeve extending beyond the respective free end of that member, and a transparent sleeve coaxially surrounding said members and sleeves and extending beyond them at both ends, said transparent sleeve said members and said insulation supporting sleeves being radially deformable into mutually interlocked relationship, to compress the sleeve members into electrical contact with the bare ends of wire and the insulation supporting sleeves into locking engagement with the insulation on the wire.

WILLIAM F. BROSKE.

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

UNITED STATES PATENTS OTHER REFERENCES Electrical Equipment, January 1944, page '7.

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