GB361891A - Improvements in electro-magnetic interrupters, impulsing devices or the like - Google Patents

Abstract

361,891. Electromagnetic interrupters. SIEMENS & GENERAL ELECTRIC RAILWAY SIGNAL CO., Ltd., Caxton House, Tothill Street, RIDDLE, H. J. N. and CANDLER, J. E., Central House, Kingsway, both in London. July 23, 1930, No. 22227. [Class 38 (v).] Retarding devices.-An electromagnetic interrupter or impulsing device of the kind in which the armature is adapted to perform a series of successive movements and to actuate a retarding device for controlling the frequency of said movements is so arranged that the movement of the armature effects movement of a movable member associated with the retarding device to short-circuit the electromagnet and thereby initiate the next movement of the armature. As shown in Fig. 1, the armature 5 when attracted to the cone 1 of the electromagnet 2 the circuit of which is closed at contacts 24, 25, Fig. 2, stores energy in a spring 11 driving upwardly two separately pivoted contactcarrying members 12, 14 the latter of which move slowly under the action of a mercury dashpot 16. At the end of the retarded movement an upper contact 23 on the arm 14 engages a relatively fixed constant 18 short-circuiting the coil 2 through a resistance 29. The consequent release of the armature 5 allows the armature 5 together with the arm 12 to fall without retardation of the arm 14 following slowly under the action of the dashpot 16. At the end of the fall of the member 14 the contacts 24, 25 again come into engagement to complete the circuit of the electromagnet 2 so that a further cycle of operations is initiated. The tuning may be varied by altering the amount of travel of the arms 12, 14 for which purpose the arm 17 carrying the contact 18 is pivotally mounted on the shaft 13 and has an extension pressed by a spring 20 against the periphery of an adjustable cam 19 which may be adjusted by a knob 21. The connection between the armature 5 and the arm 12 consist of a rod 2 pivoted to the latter and surrounded by the spring 11 the lower end passing through an extension of the armature which is prevented from sliding off the latter by a stop 10. The movements of the armature may drive intermittently a rotary switch through ratchet-and-pawl mechanism 7, 8.