GB597088A - Improvements in or relating to torque-producing electro-responsive devices - Google Patents

Abstract

597,088. Electromagnetic relays; protective cut - out arrangements. WESTING- HOUSE ELECTRIC INTERNATIONAL CO. Sept. 19, 1944, No. 17875. Convention date, Sept. 22, 1943. [Class 38(v)] [Also in Group XXXVI] A torque-producing relay is energised by means responsive to a product, e.g. (E + I) (E - I), of different vectorial sum of E and I where these symbols represent alternating- current functions of line-voltage and linecurrent. A loop 10, pivoted at 11 and carrying a contact arm 19, is energised by flux produced in a core member 7 by current flowing in coils 17, 18. This loop reacts with the flux produced in an air-gap 8 by current flowing in coils 15, 16, mounted on a central leg 5 of the same core. If the flux produced in the member 7 is proportional to (E + I) and the flux in the air-gap 8 is proportional to (E - I), the torque produced is proportional to (E<2> - I<2>) and the relay responds to apparent line-impedance. By proper selection of the exciting-currents in the windings 15-18 and in some cases by the use of a phase-shifter, the relay may be made responsive to reactance or resistance or it may serve as a directional, differential of overcurrent relay. In a modified form, Fig. 3, the voltage and current functions are combined in three-winding transformers 29, 30 to obtain secondary currents Is and ID which produce fluxes in poles 52, 54 and 51, 53, proportional to (E + I) and (E - I). Conducting loops A, B form a pivoted framework carrying the contact-arm 19 and each flux induces a current in one of the loops which reacts with the other flux to produce a torque. The Specfication as open to inspection under Sect. 91 comprises also a reference to the omission of one or more of the windings shown in Fig. 1 in order to obtain reaction or directional response. This subjectmatter does not appear in the Specification as accepted.