US 3605079 A
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United States Patent Inventor Hans Wernhard Schneider Castle Works, High St., Old Woking, Surrey, England App! No 9,328 Filed Feb. 6,1970 Patented Sept. 14. 1971 Priority Feb. 13, 1969 Great Britain 7895/69 ELECTRICAL TERMINAL CONNECTIONS 4 Claims, 3 Drawing Figs.
U.S. Cl 339/276 R,
174/87, 200/166 CT, 339/277 R Int. Cl H0lr 11/08 Field of Search 339/276,
 References Cited UNITED STATES PATENTS 2,284,384 5/1942 Evans 339/276 2,796,458 6/1957 Hartmann 174/74 2,825,041 2/1958 Meyer 339/263 Primary Examiner-Joseph H. McGlynn Attorney-Stevens, Davis, Miller & Mosher ABSTRACT: An electrical contact assembly comprises an apertured tag through which the bare end of a conductive wire passes. A tang projects rearwardly from the aperture to lie alongside the wire and a sleeve surrounds the tang and wire. The sleeve is crimped to press the wire into conductive relationship with the tang and hence the tag.
ELECTRICAL TERMINAL CONNECTIONS This invention relates to electrical connections where it is desired to connect, for example, an electrical conducting cable or wire to a tag or its equivalent, the present invention avoiding the necessity for a soldering operation.
The present invention is particularly applicable to electric switches particularly miniature electric switches of the rotary type in which the fixed electrical contacts take the form of .thin metal pressings located within the switch casing, the contacts being designed for the attachment of flexible electric conducting wires by a soldering operation.
The chief object of the invention is not only to avoid the necessity for the soldering operation but to provide a better and more secure attachment for the conducting wires with a maximum area of surface contact consistent with the size of the tags or their equivalents.
According to the present invention each tag or its equivalent is formed with a projecting tang or other projection to which the end of the conducting wire is attached by means of an enclosing tubular sleeve or its equivalent which is pinched to grip both tang and wire to provide a good electrical connection.
Preferably the pinching process is such that the tang and wire will be bent or kinked at a point intermediate its length so that the wire will be more firmly resistant to any pulling force to which it may be subjected during use.
Although it is within the scope of the invention to employ a simple metal sleeve open at both ends or closed at one end like a thimble or ferrule it is preferred that the sleeve shall be open at both ends, one end being formed with a peripheral flange, the sleeve being almost identical with a tubular rivet.
A particular embodiment of the invention will now be described by way of example and with reference to the accompanying drawings wherein:
FIG. 1 is a view (10 times magnified) of the parts constituting the contact assembly in accordance with the particular embodiment and cable end part to be connected to the assembly;
FIG. 2 is a plan view of the assembly connected to the cable end part; and
FIG. 3 is a section on the line IlI-Ill of FIG. 2.
A tag I, see particularly FIG. 2, is pressed out of sheet metal and forms a fixed electrical contact in a miniature electric switch. The tag I, viewed in plan, has a square part 2 which receives the cable and a curved part 3 which forms the switch contact. An elongate rectangular slot 4 extends from one front corner of the tag part 2 to a position centrally of the said part. A tang 5 extends at right angles to the plane of the tag 1 from the inner end of the slot 4. The tang 5 and the slot 4 are formed by a pressing operation out of an unslotted tag blank. The rear end part 6 of the tang 5 is thus pointed.
The front bare conductive end part 7 of an insulated cable 8 is dimensioned for insertion through the'inner end part of the slot 4 and to lie alongside the tang 5. A sleeve 9, generally in the form of a rivet, has a cylindrical body 10 which is dimensioned to surround the tang 5 and cable part 7 and a radially extending end flange 11 which seats against the tag 1.
In use, as can be seen in FIGS. 2 and 3, the bare front end part 7 of the cable 8 is passed through the slot 4 until the end of the insulating cover on the cable contacts the under side of the tag 1, the bare end part 7 of the cable lying parallel with and adjacent the tang 5. The flanged sleeve 9 is then slipped over the bare end part 7 of the cable 8 and the tang 5 until the flange 11 engages the upper surface of the tag 1. The sleeve 9 is then crimped by a suitable tool so that the sleeve body 10 is partly flattened to grip the cable end part 7 and is also bent longitudinally through a right angle together with the enclosed cable end part 7 which has the effect of making a good electrical nonpulloff connection between the cable and tang l and pressing the flange ll firmly into contact with the surface of the tag l.
A suitable tool for the crimping process is a small punch acting on the sleeve body 10 at right angles to its length, the tool in no way distorting the flange 11 but firmly squeezing the sleeve at a point intermediate its length and bending its extremity at right angles and at the same time flattening the extremity of the sleeve.
It will be appreciated that if the tag is enclosed completely within the casing of the switch, connection of the cable and tag will have to be made before the casing is finally closed by the attachment of the usual casing cover, the cable projecting through a hole in the cover, the bare metal sleeve and tag being completely insulated by the switch casing to comply with safety regulations.
Iclaim: 1. A contact assembly comprising: an electrically conductive element securable to an electrical component such as a switch;
structure defining a passage through the said element through which the conductive end part of an elongate conductor can be inserted to project from a face of the element;
an electrically conductive projection extending from said face of the element alongside the projecting conductive end part; and
a sleeve dimensioned to surround the projection and the projecting conductive end part with one end of the sleeve abutting the element, the sleeve being deformable to hold the projection and conductive end part in electrical connection with one another.
2. The assembly of claim 1 wherein the sleeve in the functional position is deformed into two parts generally at right angles to one another.
3. The assembly of claim 1 wherein the electrically conductive element is a flat tag, slotted to define the passage, and wherein the projection is a tang extending from one end of the slot.
4. The assembly of claim 3 wherein the sleeve is cylindrical and wherein a radial flange is provided at the end of the sleeve which abuts the tag.