GB643445A - Improvements in and relating to arc lamps and circuits therefor - Google Patents

Abstract

643,445. Supply systems for discharge lamps. REICHINSTEIN, D. March 7, 1946, Nos. 7180 and 7181. Convention dates, March 7, 1945, and Sept. 12, 1945. [Class 38 (iv)] [Also in Group XL (a)] An arc lamp with incandescent electrodes and an auxiliary electrode is incorporated in a circuit including a transformer and a signal lamp which are so arranged that when connected to lighting mains an auxiliary arc can be caused to pass from the auxiliary electrode to one of the main electrodes, and when in addition the circuit to the main electrodes is completed, the signal lamp is illuminated and remains illuminated until the existing auxiliary arc has passed over to the main electrodes, whereupon the signal lamp is automatically extinguished and thereby indicates that the main electrodes can be switched over to the mains and the transformer put out of circuit. The circuit -diagram, Fig. 2, shows the main electrodes 37, 47, the auxiliary electrode 48, the transformer primary windings 36-46 and 38-39 and secondary windings 40-42 and 43-41, and the signal lamp 50. I, II, III, IV indicates a 4. or 3-step, 2-pole sliding lever or roller switch for effecting the following connections. Step I : 29 is connected with 33 and 30 with 34, whereby the main 51 is connected to the primary winding of the transformer. Step II: previous connections maintained and at same time 24 is connected with 26, and 28 with 27, whereby main electrode 37 is con. nected with terminal 40 of secondary winding, and terminal 41 of secondary winding is connected with auxiliary electrode 48. By pressing switch 35 the auxiliary electrode 48 is connected with the secondary winding of the transformer and becomes incandescent to cause formation of an auxiliary arc between auxiliary electrode 48 and main electrode 37. Step III: connections 29 and 33, 30 and 34, 24 and 26 are maintained while 28 is now connected to 26, whereby the other main electrode is connected with terminal 41 of the secondary winding of the transformer while the signal lamp 50 is connected into the circuit of the auxiliary arc. The arc then passes on to the second main electrode and, when the latter is sufficiently heated by the arc the lamp 50 is extinguished indicating that the arc lamp can be switched over to Step IV: wherein connections 29 and 33 and 30 and 34 are broken while 24 is connected with 29, and 25 with 30, thus excluding the transformer and connecting the lamp to the main. Step I can be eliminated.