GB423488A - Improvements in relays for electrical remote control systems - Google Patents

Abstract

423,488. Electromagnetic switches. LANDIS & GYR AKT.-GES., 1, Hofstrasse, Zug, Switzerland. Sept. 12, 1934, No. 26155. Convention date, Sept. 15, 1933. [Class 38 (v)] In an electric remote-control control system in which a number of relays are operated by trains of rapid current impulses, additional relays are provided which are so arranged as not to be operated by such trains of impulses but to respond to single current impulses of substantial duration. As shown in the Figure across one conductor of a supply system 1, and a control or pilot wire 1<a> are connected a series of relays 3 which respond to a definite number of short current impulses. An additional relay is, however provided to control the circuit of a consuming device 5 in response to a single current impulse in the control circuit of substantial duration, e.g. a few seconds, and the relay is arranged to be unaffected by the impulse trains operating the relays 3. The additional relay comprises an electromagnet 4 arranged on energization by a relatively long current impulse to attract a pivoted armature 6 against a spring 7 and allow contacts 9 in the energizing circuit of an induction disc motor 11 to close. The motor disc drives through gearing 12 .. 16 a detent 17 which normally holds down a latch 30 so that its hooked end 32 is out of the path of a projection 35 on the armature 6. With a long, steady current impulse the projection 35 has moved past the hook 32 before the latter is moved into its path by the release of the lever 30 by the detent 17. During the release movement of the detent 17 a slotted projection carried by the intermediate shaft 14 moves to the succeeding tooth of a wheel 23 so that at the end of the current impulse a cam 25 is caused to engage and close contacts 26 in the circuit of the controlled apparatus 5. If however a series of short rapid current impulses are transmitted to operate relays 3, the intermittent closing of the motor circuit by the vibrating armature 6 at contacts 9, either produces only a small series of movements of the driven members or may, in case of increased intermittent energization of the motor cause the hooked end of the lever 32 to be moved into the path of the projection 35 and arrest further vibration of armature 6. The controlled circuit of the apparatus 5 is not closed as the operating detent 18 is not moved through a sufficient angle. Any small deviations of the wheel 23 from the position shown, due to vibration of the member 18, are neutralized by a spring 27 bearing on a flattened member 24 secured to the shaft 26 bearing the toothed wheel 23 and cam 25.