GB1347484A - Rotary electromagnetic devices - Google Patents

Abstract

1347484 Selsyn machines ELLIOTT BROS (LONDON) Ltd 2 July 1971 [2 July 1970] 32167/70 Heading H2A [Also in Division H1] In a brushless synchro including a transformer having a stator section and a rotor section for supplying current to the synchro rotor winding, the stator and rotor sections of the transformer being concentric, a core of the transformer comprises a plurality of axially extending laminations supported in angularly spaced relationship by an electrically insulating bonding agent. In the synchro shown, the rotor core 13 of the transformer comprises a plurality of U-shaped laminations 18 secured together by a thermosetting synthetic resin, e.g. an epoxy resin. The transformer secondary winding 11 is mounted on the base portion 20 of the laminations. The transformer stator core 14 comprises L-shaped laminations 21 secured together by epoxy resin. The stator magnetic circuit is completed by a ferromagnetic disc 24 of solid or laminated construction. In a modification, Fig. 2 (not shown), the stator core is made of U- shaped laminations as in the case of the rotor core, but with the limbs of the U pointing radially inwards. The stator winding and core are impregnated with epoxy resin to form a unitary structure. The peripheries of the limbs of the rotor and stator cores may each carry a continuous ferromagnetic ring (e.g. 32, Fig. 2) to reduce the cogging effect of the laminations. As shown, the transformer rotor and the main synchro rotor 1 are mounted on a shaft 5 carried in bearings 6 mounted in bearing housings 7 by C- springs 9.