GB190516301A - Improvements in Electric Arc Lamps. - Google Patents

Abstract

16,301. Johnson, W. C., and Thomson, M. P. Aug. 10. Arc lamps.-One of the electrodes C, Fig. 1, is supported by a stop a, shaped as shown in Fig. 6, and adjustably held by a set-screw (not shown) in the wall of a box b. The electrode holders C<1> are attached to frames f, which slide on rods g and are connected together by means of pins h and grooved arms. To strike the arc, the positive electrode is rocked about the pins h by means of a weighted cradle i, pivoted at k. The carbons are brought together, when no current flows, by the contraction of a wirej connected in series with the carbons, or by the weight of a series-solenoid core, which is situated at the upper end of the lamp and carries a rod having a reduced end passing through a perforated arm of the cradle. A pair of frame-rods, of which Fig. 1 only shows the ends d, are covered with insulating-enamel and wound with bare wire so as to form an arc-controlling electro-magnet, the strength of which may be adjusted by means of contact-sleeves movable over the coils. The baseplate c and box b are of non-magnetic material, and are insulated from each other. The box is divided by a gap b<1>, mainly at right-angles to the carbons, and serves to extinguish the arc when the carbons have reached the end of their feed; the bottom b<2> of the box forms a reflector.