GB775302A - Improvements relating to polarised electro-magnetic relays - Google Patents

Abstract

775,302. Electromagnetic relays. TELEPHONE MANUFACTURING CO., Ltd. March 2, 1955 [March 5, 1954], No. 6543/54. Class 38(5) A polarized relay in. which the contact structure is separate from and connectible to the magnetic driving structure, employs a magnetic structure generally as disclosed in Specification 619,546 with reference to Figs. 1-4, the armature 3 of the present invention, however, does hot carry the moving contacts but operates the latter by a pair of hard insulating balls 4. The contact structure is mounted on a base plate 7 having a pair of lugs 6 fixed by screws to the upper end of the magnetic structure (Fig. 1, not shown), the contact structure comprising fixed contact strips 22 and moving contact strips 15, 16 separated by a pair of outer insulators 17, 18 and a pair of central insulators 19, 20. The assembly is held together in a stack by bolts 8 and nuts 9, the bolts electrically connecting their respective contacts 22 but being insulated from the contacts 15, 16 by insulating sleeves 24. The stack is mounted on the plate 7 by a pair of screws 10 passing through holes 10a in the insulators 19, 20 and slots 11 in the plate 7, and screwing into a plate 12 beneath the plate 7. Openings 13, 14 in the plates 7. 12 permit passage of the armature 3. By slackening the screws 10 to move them in the slots 11 the relay may be centre stable (as shown), or one side stable. The contacts 15, 16 in their unoperated condition are stressed against upstanding posts 25 formed on the insulators 19, 20, and the position of the contacts 22 is adjustable by screws 27 threaded therein which engage parts 26 formed on the insulators 17, 18: The contact clamping means disclosed in Specifications 673,867 or 484,472 may be employed, and the permanent magnets used in the magnetic structure may be as disclosed in Specification 715,630.