GB394719A - Improvements in or relating to windings for dynamo-electric machines - Google Patents

Abstract

394,719. Dynamo-electric machines. STRITZL, P. F., 6, Brentfield Gardens, Hendon Way, London. Jan. 8, 1932, No. 34912/31. [Class 35.] Cores; windings.-In a dynamo-electric machine a winding arranged in open or closed slots has the front or back pitch exactly or nearly equal to double the pole pitch of the field in which the winding acts or to an integral multiple (including zero) of double the pole pitch, and permeable members are disposed so as to provide a flux path between the working faces of adjacent main field poles, a part of the path having a higher reluctance than another part; both front and back pitches may be arranged as double pitch windings but the case in which both part pitches are exactly equal to an integral multiple of double the field pole pitch is excluded. Fig. 1 shows a winding in which one pitch is approximately equal to double the pole pitch of the field, and Fig. 3 shows part of the field and armature 3 of a continuous current motor. The nett effective current is zero in slots a, c, d, e, g, h and the slots b, f which have effective current are situated in the position of maximum field strength. The brushes 4 are located opposite the centres of the main poles. Interpoles 5 arranged between the main poles 2 provide an additional path for the armature flux, undue leakage being. prevented by the spacing between the poles. The interpoles may carry shunt, series or compound windings which assist the armature field. Instead of the interpoles, the tips of adjacent main poles may constitute the permeable bridge. The windings described may be applied to the stator or rotor or to both as open or closed coil windings and may be wave or lap-connected.