Clip Connector Terminal For One Or More Insulated Conductors

Abstract

The metal contact assembly of a clip connector terminal includes a wire yoke having leg portions and a contact element disposed in the plane of the yoke, flanked by said leg portions and forming a unitary structure with said yoke. Each side of the contact element and each leg portion is provided with a sharp edge; a sharp edge of the contact element and a sharp edge of the yoke leg cooperate to cut through the insulation of an inserted conductor on diametrically opposed sides thereof and to maintain a continuous electric contact with said conductor.

Description

BACKGROUND OF THE INVENTION

This invention relates to a clip connector terminal for at least one insulated conductor and is of the type which is provided with two slots defined externally by the legs of a resilient wire yoke and internally by the sides of a contact element formed as a sharp contact knife. The end portions of the legs of the wire yoke and a part of the contact element are anchored in an insulating body or similar carrier. The reliability of contact in this and other clip connectors is determined largely by three factors: a secure cut through the insulation of the conductor, a small contact resistance between the parts of the connector and a continuous contact pressure exerted by the connector on the conductor.

In a clip connector structure described in U.S. application Ser. No. 833,024, filed June 13, 1969, in the name of Heinz Krone et al., entitled "Clip Connector Terminal for Insulated Conductors," the reliability of contact with respect to the aforenoted factors is in most cases very satisfactorily ensured. During the insertion of an insulated conductor into the clip connector, the insulation is, on one side, cut through by a sharp edge of the contact element and, on the other, diametrically opposed side, squeezed or pushed away by a leg of the resilient wire yoke, so that an electric contact results between the wire yoke and the conductor as well. It may occur, however, that because of the round profile of the yoke wire, the insulation of the conductor is only deformed to such an extent that, in the course of time, because of its stressed condition, it returns and again covers the previously exposed surfaces. Upon such an occurrence, electric contact will exist only between one side of the conductor and the sharp edge of the contact element. Further, the common anchoring of the contact element and the wire yoke in the carrier body by inserting the yoke ends through openings of the lower portion of the contact element, usually results in satisfactory low contact resistance, but may, nevertheless, constitute a trouble spot.

OBJECT, SUMMARY AND ADVANTAGES OF THE INVENTION

It is an object of the invention to provide an improved clip connector of the aforenoted type in which the reliability of electrical contact is ameliorated particularly with respect to the afore-listed three factors.

Briefly stated, according to the invention, the leg portions of the resilient wire yokes too are formed as sharp contact knives along the locations of possible contact with the conductor and further, the wire yoke forms, with the contact element, an integral mechanical and electrical unit.

In this manner, the insulation of the conductor attached to the clip connector is cut through securely by both the contact element and the wire yoke, ensuring a continuous good contact pressure on the conductor and further, the contact resistances between the conductor and the clip connector as well as between the contact element and the resilient wire yoke in the carrier body are maintained at all times at a very small value .

The invention will be better understood and further objects as well as advantages of the invention will become more apparent from the ensuing detailed specification of several exemplary embodiments taken in conjunction with the drawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective view of a first embodiment of the invention;

FIG. 2 is a perspective view of a second embodiment of the invention;

FIG. 3 is a front elevational view of a third embodiment of the invention;

FIG. 3a is a side elevational view of the same embodiment;

FIG. 4 is a front elevational view of a further embodiment of the invention;

FIG. 4a is a side elevational view of the same embodiment;

FIG. 5 is a front elevational view of still another embodiment of the invention;

FIG. 6 is a perspective view of the embodiment of FIG. 1 with a modification; and

FIG. 7 is a perspective view of an embodiment according to FIG. 2 with a modification.

DESCRIPTION OF THE EMBODIMENTS

Turning now to the embodiment shown in FIG. 1, the clip connector shown therein is formed essentially of an inner leaf-like contact element 1a and a contact yoke 1b surrounding the contact element 1a. The contact element 1a and the contact yoke 1b form a structurally integral, unitary contact assembly 1 anchored in an insulating carrier 2.

For establishing a contact between the clip connector and a conductor, there is provided a pusher slide of the type shown and described in the aforenoted U.S. Patent Application, but not illustrated or described here.

The contact element 1a is of rectangular cross-section and is formed at the linear flanks 1a' and 1a", at the end which emerges from the insulating carrier 2, as a sharp-edged contact knife. The contact element 1a merges, in the range of the insulating carrier, into a resilient rectangular contact yoke 1b which surrounds the contact element 1a and which forms with the flanks 1a' and 1a" the insertion openings a and b. The legs 1b' and 1b" of the contact yoke 1b are at their flanks 1b"' and 1b"", facing the contact element 1a, also formed as sharp-edged contact knives. At the lower end of the contact assembly 1 there extends downwardly a terminal strip 1ab.

To ensure a satisfactory resiliency of the contact yoke 1b, there are provided gaps or loops c and d between the yoke legs and the contact element. The legs of the contact yoke 1b are, in the range where the conductor is inserted, slightly divergent to thus form insertion slots a' and b'.

The contact assembly 1 may be a stamped unit and is preferably made of a highly conductive copper alloy.

To establish an electric contact between the clip connector and an insulated conductor 3, the latter is threaded through the contact yoke 1b and is positioned on the support faces e, and f, or g and h, which form part of the contact yoke 1b and the contact element 1a.

The guiding means for conductor 3 is provided on the one hand, by the inner flanks of the contact yoke legs 1b' or 1b" and, on the other hand, by the rounded end portion 1a'" of the contact element 1a.

In the embodiment according to FIGS. 6 and 7 there are provided additional oblique guide shoulders i and k which extend outwardly from the respective support faces e and h of the contact yoke.

Thereafter, the insulated conductor (or conductors) 3 is, by means of a pusher slide (not shown), pressed into the wedge-shaped slot opening a' and b' which has a width slightly smaller than the diameter of the metal conductor 3a.

As a conductor 3 is pressed into the slot a' and b', the insulation is progressively cut through, on the one side of the conductor, by the sharp-edged flanks 1a' and 1a" of the contact element 1a and, on the other, diametrically opposed side of the conductor, by the sharp-edged flanks 1b'" and 1b"". As conductor 3 reaches its final position at the location A or B, the sharp-edged flanks of the cooperating contact parts have penetrated into the material of the metal conductor 3a.

Turning now to FIG. 2, the embodiment shown therein differs from the previously described embodiment merely in that two separately stamped parts are used for the yoke and the contact element. In their assembled condition, however, the two parts form an integral mechanical and electrical unit. Both the contact element 4 and the yoke 5 have a respective, planar, plate-like integral lower part 4a and 4b which are in a face-to-face relationship and may be welded together. The thus unified plate-like parts 4a, 4b are embedded in the carrier body 2. The contact element 4 is bent out of the plane of its associated plate 4a to extend in a coplanar manner with respect to yoke 5. The relatively large contact area between the aforenamed two parts ensures a small contact resistance which, in turn, is the measure for a reliable electrical contact.

The terminal strip 4b forms a unitary part with the contact element 4. In FIG. 3 there is shown an embodiment of the invention adapted to receive up to four conductors between leg portions of a twin contact yoke 7 and flanks of a twin contact element 6. Both parts may be stamped components.

Turning now to FIGS. 4 and 4a, the embodiment shown therein includes a wire yoke 7b with an interposed contact element 6b for receiving two conductors and further includes a unitary wire yoke 7a integral with the wire yoke 7b. The wire yoke 7a, however, does not contain an interposed contact element. Consequently, a conductor inserted in the yoke 7a is contacted at both, diametrically opposed sides, by opposed leg portions of yoke 7a.

The embodiment according to FIG. 5 comprises integral tripple yokes 7c, 7d, 7e. The yokes are upwardly closed and are united at their lower end to form a plate-like member.

Claims

That which is claimed is:

1. A clip connector terminal for insulated conductors, comprising:

A. at least two cooperating contact members each provided with a knife edge, one of said contact members being formed of a central contact element having two sides provided with knife edges, each contact member being so spaced from its associated, cooperating contact member that upon insertion of said insulated conductor the knife edges of said cooperating contact members cut through the insulation of said conductor and establish an electric contact with diametrically opposite sides of said conductor;

B. a wire yoke in the shape of a closed loop, said wire yoke including two leg portions constituting two of said contact members which surround at least partially said central contact element, with each leg portion extending along either side of said central contact element with the knife edge on each leg portion cooperating with the knife edge of the immediately adjacent side of said central contact element, and resiliently yielding in a direction away from its cooperating contact member upon insertion of said conductor, said electric contact being maintained by a resilient force urging each leg portion towards its cooperating contact member, said yoke and said central contact element both having a plate-like terminal portion bonded together face-to-face, with said central contact element being bent out of the plane of its associated plate-like terminal portion and extending coplanar with said yoke between the leg portions thereof;

C. means joining said contact members at one end remote from the loop connection between said leg portions; and

D. insulated carrier means in which said last-named end of said contact members is anchored.

2. A clip connector terminal for insulated conductors, comprising:

A. at least two cooperating contact members each provided with a knife edge, each contact member being so spaced from its associated, cooperating contact member that upon insertion of said insulated conductor the knife edges of said cooperating contact members cut through the insulation of said conductor and establish an electric contact with diametrically opposite sides of said conductor;

B. two wire yokes being arranged in a juxtaposed relationship, each in the shape of a closed loop, and each including two leg portions which constitute contact members, each leg portion resiliently yielding in a direction away from its cooperating contact member upon insertion of said conductor, said electric contact being maintained by a resilient force urging each leg portion towards its cooperating contact member, said yokes being connected to one another at their ends remote from the loop connection between the leg portions of each yoke, the leg portions of one of said wire yokes being immediately adjacent to and cooperating with one another in establishing and maintaining said electric contact with a conductor, between the leg portions of the other of said wire yoke there being disposed a central contact element having two sides provided with knife edges, the last-named wire yoke surrounding at least partially said central contact element, said leg portions of the last-named wire yoke extending along either side of said contact element, the knife edge on each of the last-named leg portions cooperating with the knife edge of the immediately adjacent side of said central contact element, said wire yokes and said central contact element forming a secure mechanical and electrical unit;

C. means joining said contact members at one end remote from the loop connection between said leg portions; and

D. insulated carrier means in which said last-named end of said contact members is anchored.