GB147804A - Improvements in or relating to electric arc lamps for searchlights or projectors - Google Patents

Abstract

147,804. Siemens - Schuckertwerke. April 5, 1917, [Convention date]. Arc lamps.-A lamp suitable for use in a projector or searchlight has means for constantly feeding the electrodes by an electric motor, clockwork, ratchet gear, or the like, at a speed corresponding to their normal consumption, and also means controlled by hand or electrically for compensating for irregularities in the consumption. In one arrangement, the constant-feed and regulating-motors drive through worm gear a screw and a long pinion respectively. A nut on the screw is embraced by the electrode-holder and is toothed to engage the pinion. In another construction, a constant-speed motor 15, Fig. 2, drives one sun-wheel 25 of a differential gear through worm gear, and also rotates two spur wheels 29, 31 in opposite directions. A pinion 32 geared to the other sun-wheel 26 is shifted into mesh with one or other of the wheels 29, 31 by electro-magnets 37, 38 governed by a differential relay 33, 34. The planet-wheel 27 is carried by the feed-screw 12. A pinion 40 revolubly secured to the carbon-holder 11 and splined on the feedscrew imparts rotation to the carbon 44. Either or both of the electrodes may be thus rotated. The regulating-mechanism may, if desired, be cut out or may be locked with the pinion 32 in its central inoperative position, when hand regulation is desired.