GB178438A - Damping device for switch contacts for electro-magnetic vibrating members - Google Patents

Abstract

178,438. Ma¯tre, A. H., and Martin, V. H. G. April 18, 1921, [Convention date]. Electrically - vibrated instruments. Relates to means for damping rapidly the oscillatory motion of an electromagnetically vibrated body such as a stretched string &c., as described in Specification 3583/14. As applied to the vibration of a stretched wire, Fig. 1, the main electromagnet b is in series with a make and break electromagnet b<1> which rocks a weighted lever c pivoted at c<2> and makes and breaks contact at c<1>, a<1>. A fluid dash-pot j, k is attached to the lever c at j<2> to damp out the vibrations. The Specification as open to inspection under Sect. 91 (3) (a) describes also retarding means applied to the gong vibrator described in the said prior Specification; a felt pad, adjustably mounted, presses lightly on an extension of the armature member and damps out the oscillation. The pad is mounted on a wire and rubs on a lateral extension of the armature spindle. The vibrating contact consists of a bundle of silver wires co-operating with a " fixed " contact mounted on a wire adjustably held at one end and in engagement with the gong at the other so that it oscillates synchronously with the gong. This subject-matter does not appear in the Specification as accepted.