GB788658A - An electric discharge lamp arrangement - Google Patents

Abstract

788,658. Control systems for electric discharge apparatus. QUARZLAMPEN GES. July 28, 1954 [July 28, 1953], No. 22051/54. Class 38 (4). [Also in Group XL (a)] A high-pressure xenon discharge lamp 1 has a tubular extension containing a rod 4 carrying a movable electrode 2, the rod being surrounded by a metal tube and provided with a small block 6 of ferromagnetic material movable by a magnet 7. The magnet 7 is movable on a screwed spindle 9 which is rotated by an electric motor 10 in circuit with the switch 16 in the lamp circuit to move the electrode 2 into and out of contact with the stationary electrode 3. A contactor 11 has an operating coil serially connected in the operational circuit of the discharge lamp and change-over contacts 12 inserted in the energizing circuit of the motor, the arrangement being such that when the contactor is operated by the discharge current, the energizing circuit is connected for a directicn of the motor's rotation in which the magnet 7 and electrode 2 are moved away from the stationary electrode 3, whilst when the contactor releases, the energizing circuit of the motor is changed over for movement of the magnet 7 and electrode 2 towards the stationary electrode 3. At each end position of the magnet 7 on the spindle 9 a switch 13, 14 is arranged which is opened by arms fixed to the magnet and which is connected into the motor circuit by a change-over switch 15 actuated by the contactor 11 in such manner that, if the magnet 7 moves towards one of the switches 13, 14, this switch is inserted into the motor circuit. A clutch can be inserted between the spindle 9 and the motor 10 to avoid over-running.