GB272574A - Improvements in electro-magnetically operated indicating instruments or relays - Google Patents

Abstract

272,574. General Electric Co., Ltd., and Angold, A. E. March 3, 1926. E l e c t r o magnetic switches. - A relav comprises a pivotally mounted magnet having a pole biassed towards a point at or near the centre of the length of a relatively long solenoid and adapted to move parallel to the axis of the solenoid. Within definite limits of movement, the force acting on the magnet is substantially proportional to the value of the current in the solenoid since the poles of the solenoid have no effect on the magnet. As shown a pivotally mounted bar magnet 4 co-operates with the solenoids 2, 3 wound in series on an iron ring 1 to produce when current flows torques which act on the magnet in the same direction and consequent poles at the unwound portions of the ring 1. Separate solenoids may be employed to produce a differential torque or movement of the magnet in one or other direction. Instead of a single bar magnet a group of magnets or an electromagnet may be employed. The solenoids mav be arranged on arcs of different radii. The Provisional Specification states that the consequent poles may be utilized for producing an adequate closing force for the contacts of the relay.