GB414273A - Dimming adapters for electric incandescent lamps - Google Patents

Abstract

414,273. Electric incandescent lamps. SOPER, H. N., KNAPP, V. G., and JONES, G. V. WYNNE-, (trading as VIVIAN & CO.), 99, Regent Street, London. Dec. 7, 1933, No. 34445. [Class 39 (ii).] An adapter for electric incandescent lamps, of the kind containing a resistance for altering the illumination, is provided with a rotary switch element 16, Figs. 4 and 7, having a pair of arcuate conducting-sections 17 coacting with a pair of non-rotatable contact fingers 14 across which a resistance 12 is connected, the whole resistance being placed in series with a lamp within the holder in one position of the switch, and being short-circuit by the conducting- sections 17 when in the other position, thereby giving alternatively either a dim or " full-on " illumination from the lamp. The adapter is made in upper and lower portions 1, 2 which form a hollow interior containing the body portion 5a carrying the plunger contacts 13 and bayonet socket 8, together with a ring 18 provided with leaf-spring pawls which cooperate with, and rotate, the switch element or ring 16 when a chain 20 attached to the ring 18 is pulled intermittently against the tension of a helical spring 22. The contact sections 17 are mounted on the upper face of the ring 16 to co-operate with the pair of contact fingers 14, one of which is connected to an upper plug terminal of the adapter while the other is connected to a plunger terminal 13 of the socket. The bottom face of the ring 16 is formed with ratchet teeth 23<a>, Fig. 5, which are engaged by pawls 23 on the ring 18 when the latter is oscillated by the pull chain 2. The resistance 12 is mounted on a ring within a circular recess 10 in the upper part 1 of the adapter. Ventilation holes 24 are provided.