GB830605A - Improvements in or relating to electromagnetic relays - Google Patents

Abstract

830,605. Electromagnetic relays. SMITH & SONS (ENGLAND) Ltd., S. Oct. 29, 1956 [Oct. 27, 1955], No. 30769/55. Class 38 (5). A relay insensitive to acceleration forces comprises a coil 1 surrounding a core (not shown) and surrounded by a magnetic tube 2, the core and tube being connected at the remote end by a magnetic disc, and a brass mounting-block 3 being supported at the other, nearer, end of the core. A pair of slotted arms 4 on the block receive, respectively, armatures 8, 9 pivoted at their centres of mass about an axis 10. An inner polepiece 11 connected to the nearer end of the core co-operates with the lower end of armature 8 and a similar polepiece (not shown) co-operates with the upper end of the armature 9; also, an outer polepiece 13 on a tongue 12 extending from the tube 2 co-operates with the upper end of the armature 8 and a similar polepiece (not shown), co-operates with the lower end of armature 9. Thus when the coil 1 is energized the armatures rotate in opposite directions to bridge their respective pairs of polepieces. The ends of the armatures are connected by pins 19 of a pair of non-magnetic bars 14 pivoted on the block 3 about an axis .15, this axis being at right-angles to and in the same plane as, the axis 10. The bars 14 carry insulating contact-actuating forks 16 and the axis 15 passes through the centres of mass of the bar and fork units. Each fork 16 controls a respective contact blade 23 operating between fixed contacts 21, 22, the blade being moved to engage its contact 22 when the coil 1 is energized and the inherent bias of the blades restoring them against their contacts 21 and returning the armatures, when the coil is deenergized.