GB578121A - Improvements in dynamo-electric machines for the remote transmission of angular motion and torque - Google Patents

Abstract

578,121. Remote control systems. BRITISH THOMSON-HOUSTON CO., Ltd., MAGGS, A. H., CHOUDHURY, S-U A., and CLARK, L. J. Dec. 18, 1942, No. 17991. [Class 40 (i)] In a resultant field system using a selsyn receiver, the transmitter comprises a commutated winding 1 fed with single phase A.C. over brushes b movable relatively to the winding which is arranged to supply suitable secondary voltages to the windings 3 of the receiver the other winding 6 of which is also fed with single phase A.C., the single phase voltage being stepped down for application to the commutated winding and the secondary voltages being stepped up for application to the line. The step-down is effected by a transformer or auto-transformer 7 and the step-up, as shown, by corresponding transformers 5 at the outgoing end of the line. Transformer 5 may be combined in one unit like a polyphase transformer. In a modification, the step-up is effected by taking the secondary voltages from a winding inductively related to and wound in the same slots as the commutated winding. The magnetic circuit of the commutator winding may be completed by a stator core or the windings may be situated in deep slots having narrow openings as in Fig. 6 (not shown). Either the brushes b or the winding 1 may be movable, or if the sum or difference effects are required, both are movable. The transmitter enables high operating voltages to be employed, sparking at the commutator brushes being minimized, also, the input torque at the transmitter, which is operated manually or by a motor, is small and independent of the output of the receiver. The initial rate of growth of torque at the receiver is however, low, but this may be increased at the expense of maximum torque by employing short circuiting transmitter brushes at an angle of 90 degrees to brushes b, or by using pairs of brushes b as shown in Fig. 5, or further, by using a short-circuited quadration winding on member 2 at the receiver.