GB214587A - Improvements in or relating to electric motors - Google Patents

Abstract

214,587. Torda, L. April 17, 1923, [Convention date]. Exciting; pole-pieces and cores.-The compensating - coils in salient-pole commutator motors of small radial dimensions and having air gaps of constant width are arranged so as to bridge over the space between two adjacent poles and are disposed in slots which divide the pole faces into substantially equal parts. Fig. 3 shows a form in which each pole N, S is divided on the plane d into two parts, secured together by screws, and has a central slot a for the compensating coil A which shows the space between the poles. In the form shown in Fig. 4, each pole has two slots, one for each of the two adjacent .compensating-coils A, B. The pole is made in three parts C, C', C, divided by non- radial planes at d. The part C<1> is just secured to the yoke by screwing at f<1>; the main coil e and the compensating coils A, B are then inserted; and finally the members C, C are introduced and secured by screwing at f. The num- 'ber of compensating ampere-turns per pole is less than the number of armature ampere-turns embraced by the pole shoe, but is greater than one greater of that number.