GB356268A - Improvements in electromagnetic clutches - Google Patents

Abstract

356,268. Electromagnetic clutches. CARR, L. H. A., Oakleigh, Cambridge Road, Hale, Cheshire, and ASSOCIATED ELECTRICAL INDUSTRIES, Ltd., Bush House; Aldwych, London. June 6, 1930, No. 17535. [Class 35.] In an electromagnetic clutch of the kind in which one member is supplied with continuous current and the other has phase windings closed through external variable resistances, continuous current is fed to the second member when the clutch is required to operate without slip. As shown in Fig. 1, the field member 1 is supplied with continuous current from an exciter 15 through slip rings 8, and the armature 9 of the second member 2 is provided with a threephase winding which can be connected through slip rings 11 and a three-pole change-over switch 13 either to variable resistances 14 or to the exciter 15 or other source. In a modification, Fig. 2, the change of connections is effected by a single-pole switch 16. The exciter 15 may remain permanently in circuit since at starting the resistances 14 will limit the flow of current. Either of the clutch members 1, 2 may be the driving member and the armature may surround the field. The armature winding may have any number of phases and a part only may be supplied with continuous current, the remainder being short-circuited or open circuited.