GB910561A - Improvements in or relating to electric relay contacts - Google Patents

Abstract

910,561. Switch contacts. PLESSEY CO. Ltd. July 20, 1959 [July 22, 1958], No. 23472/58. Class 38 (5). Contacts on the bifurcated ends of a resilient blade move relative to each other after engaging a fixed contact or contacts to produce a wiping action. Two pairs of such contacts 2, 3 and 4, 5 are shown in Fig. 1 on the ends of a spring 1. The limbs 10 . . . 13 are bent so that each pair of contacts is coplanar, the limbs 10, 12 being concave and the limbs 11, 13 convex when viewed from the direction of the fixed contacts 8, 9. When contacts 2, 3 engage the contact 8, the contact 2 is moved outwards owing to the decrease in curvature of the limb 10, and the contact 3 is moved inwards owing to the increase in curvature of the limb 11. Lugs 6, 7 on the spring 1 may be loosely mounted on contact-actuating means (not shown) so that if one contact sticks the wipe of another is increased. In Fig. 2 a spring blade 21, pivoted at 27, has bifurcated ends 24, 25 carrying contacts 22, 23 for engagement with contacts 28, 29 on a support 26. Owing to the differing contact heights they engage simultaneously but in different planes and further movement of the blade 21 results in relative movement of the points of contact. In a modification of this last arrangement, Fig. 3, the end of one arm 34a and one arm 36b of a bifurcated fixed support 36 are cranked; the heights of all the contacts being the same.