GB424795A - Improvements in or relating to electromagnetic relays - Google Patents

Abstract

424,795. Electromagnets. GENERAL ELECTRIC CO., Ltd., Magnet House, Kingsway, London, and ROSE, W. R., c/o General Electric Co., Stoke, Coventry. Oct. 12, 1933, No. 28162. [Class 35] [See also Group XXXVII] In an electromagnetic relay preferably of the telephone type, a portion of the armature or a member of magnetic material fixed thereto and directly attracted by the core is movable relatively to the armature for the purpose of varying the air gap between the armature and the part of the magnetic circuit of the relay towards which it is attracted on energisation, the armature being provided with a non- magnetic residual pin or pins of a predetermined size. As shown in the Figure the armature 7 carries non-magnetic pins 8 adapted on attraction to contact with the end of the core 3 to limits its inward movement. A magnetic disc 7 is screwed into the armature opposite the end of the core and is adapted on being rotated by a suitable tool to vary the air gap between the armature and the core end, the pins 8 at the same time ensuring that the travel of the armature is not affected by such variation of air gap. The magnetic member 7 may be retained in its adjusted position by the springy action of the bifurcated ends 9 of the armature or separate spring-detent locking devices, Figs. 2 and 3, (not shown), may be provided for this purpose.