GB674439A - Improvements in contact-spring assemblies for electric switching devices - Google Patents

Abstract

674,439. Electromagnetic relays. VIGREN, S. D., BROBERG, W. O. W., and ZANDER, R. A. Feb. 23, 1950. [Feb. 24, 1949] No. 4717/50. Class 38 (v). A contact spring pile-up for a relay has a common supporting-stud 4 for the fixed springs 6 ... 8, and a common actuating stud 3 for the movable springs 9 . . . 12, each stud having a number of equally-spaced teeth engaged by the springs, the arrangement being such that all of the contacts are closed by the resilience of the springs. Each stud has a tooth corresponding to each spring and the teeth on one stud are slightly offset relatively to those on the other so that the springs of one pair may be interchanged and still engage the same stud. In Fig. 1, springs 6, 12 form a "break" contact, the spring 12 normally being out of engagement with stud 3 so that the contact pressure is not reduced by the stud. Springs 7, 11 form a "make" contact, the latter normally engaging the underside of a tooth on stud 3 so as to be separated from spring 7, and springs 10, 8, 9 form a "break-beforemake" contact, which may be changed to a "make-before-break" contact by increasing the height of the contacts of spring 8 or by bending down the tip of spring 10 and bending up the tip of spring 9. The stud 3 is normally held against a strut 2 by a spring 13 which returns the stud when the electromagnet (not shown) is de-energized. In a modification, Fig. 6 (not shown), two sets of teeth, one on each side of the stud, are directed laterally of the springs.