GB1301552A - - Google Patents

Abstract

1301552 Two-part couplings PLESSEY CO Ltd 19 April 1971 [9 July 1970] 33442/70 Heading H2E An electrical contact assembly or switch board jack comprises a metal base portion 10, an insulating strip 11 e.g. of ebonite secured to base 10 by nut and screw fixings such as at 12, and a further insulating strip 14, secured by means of screws and a clamping plate 15, the contact members 16-22 and wire 23 being embedded in strip 14, which is typically of a plastics material e.g. glass-filled polycarbonate or ebonite and which may be applied by injection moulding techniques. The contact members and wire 23 are of square-section hard-drawn material e.g. cadmium copper, and their contacting areas at least may be coated with precious or semi-precious metal, the contact area being restricted to knife edges (Fig. 2, not shown). Due to their cross-section the contact members are suitable for solderless connections to be made on them where they protrude through strip 14 as at 24. To ensure that the contact members do not become dislodged under the stresses imparted by the solderless connection process it may be necessary to have a small knee formed in the contact members where they pass through strip 14. Each of the contact springs or members is of U-shaped configuration, members 17, 18, 20 and 22 being flared to give a widened free end to ensure twin contact between members (see enlarged detail of members 18 and 19). Members 16 and 19 are formed inwardly towards each other at their free ends to enable the tip and ring electrodes of a plug inserted through a hole having an interference fit metal bush 13, to contact them and at the same time deflect the said members out of contact with members 17 and 18. The movement imparted to member 19 from the plug is transmitted to member 21 via insulating sleeve 25 thus breaking contact between members 20 and 21 and making contact between members 21 and 22.