GB898948A - Improvements in and relating to control devices - Google Patents

Abstract

898,948. Magnetic switches. OAK MANUFACTURING CO. Jan. 19, 1959 [Jan. 17, 1958], No. 1859/59. Class 38 (5). [Also in Group XXXV] A magnetic switch comprises a magnetized actuating member which operates switches on the other side of a non-magnetic partition having magnetic inserts extending therethrough. In one embodiment actuating member 26 has a permanent magnet 28 mounted on a pin 27 which also carries polepieces 29, 30 which co-operate with magnetic inserts 21, 22. Mounted on the other side of partition 10 and electrically insulated from it are switches each comprising a spring arm 13 carrying a contact 16 which co-operates with a fixed contact 17. Near the centre of each arm 13 is a magnetic armature 20, sufficiently large to bridge the gap between inserts 21, 22. In modifications the partition is cylindrical instead of flat with the actuating member on a spindle coaxial with the partition (Figs. 4 and 5, not shown), and several such cylindrical controls may be arranged to operate together from the same spindle (Figs. 6 and 7, not shown). In a further modification, a pivoted construction has a snap-action (Fig. 8). In another embodiment the actuating member is moved in a straight line between three inserts to actuate a pivoted armature (Fig. 9), and this arrangement may operate by repulsion if the armature is magnetized. Instead of a permanent magnet an electromagnet may be used in any of the embodiments, and the partition may be movable instead of the magnet. The partition may be of plastic, glass, copper, brass or aluminium, and the inserts may be faced with thin layers of material to prevent sticking.