GB907519A - A sealed magnetic contact device - Google Patents

Abstract

907,519. Magnetic switches. STANDARD TELEPHONES & CABLES Ltd. June 10, 1960 [June 17, 1959], No. 20499/60. Class 38 (5). In a sealed magnetic contact device including parallel electrically conductive bars of magnetizable material, a magnetizable moving contact member is connected to one of the bars by spring means which urge the contact member away from the other bar. In Fig. 1, a U-shaped magnetic member 2 carries a magnetic contact armature 5 which is held against one end 3 of the member 2 and away from the other end 4 by a flat spring 6 welded to both members 3, 5. The normal spacing between the armature 5 and the end 4 is set during assembly by the engagement of the armature 5 with the inside of the vessel 1 before it is sealed to the member 2. After sealing the member 2 is cut along a line a-a as disclosed in Specification 829,066, so that the members 4, 5 act as contacts. As shown in Fig. 2, the device may complete the magnetic circuit between poles N, S of an electromagnet M. A second fixed contact may be sealed in the end of the vessel to be engaged by the armature 5 in the de-energized position (Fig. 3, not shown). In Fig. 5, the contact armature is a disc 12 biased by a spring 14 against the end 15 of a spindle 13 secured to the end 4. Additional non-magnetic fixed contacts 16 may be sealed in the end of the vessel 1. In Fig. 6, the armature comprises a flat spring 18 welded to the end 3 of the member 2 with its other end normally spaced from the end 4 and engaging the vessel 1.