Abstract:
1,045,441. Electromagnetic relays. STANDARD TELEPHONES & CABLES Ltd. Sept. 14, 1964 [Sept. 14, 1963], No. 37423/64. Heading H2B. A polarized electromagnetic relay in which the armature or armatures may be stable in one or both of its end of travel positions has one or more sealed magnetic contact devices with a ball-shaped contact armature which bridges fixed pairs of contact rods in one or both of said positions. In Fig. la the permanent magnet 7 is mounted between two contact devices 1 surrounded by a coil 8 and biases the armature contacts 6 to bridge an upper contact pair 2, 3. A second magnet may be mounted below the first (Fig. 2a, not shown) so that the armatures are bi-stable, as in Fig. 4 in which annular permanent magnets 10, 11 are mounted outside the coil 8 1 . Rod-shaped permanent magnets may lie alongside the coil (Figs. 5a and 6a, not shown) or annular magnets 14, 15 (Fig. 8b) may surround a number of contact devices 1 around an operating coil.