D.C. Rotary machine with interpole compensation

Claim 1

D. C. rotary maching comprising: a stator having a yoke of annular shape, a plurality of main pole cores disposed along the inner periphery of said yoke in a relation equally spaced apart by a predetermined distance from each other in the circumferential direction of said yoke, a main pole winding wound around each of said main pole cores, a plurality of interpole cores disposed along the inner periphery of said yoke at positions intermediate between said circumferentially spaced main pole cores, and a interpole winding wound around each of said interpole cores; a rotor having a rotary shaft, an armature core fixed to said shaft, and an armature winding wound around said armature core; a commutation equipment having a commutator fixedly mounted on said rotary shaft, and brushes held in a position capable of making sliding contact with said commutator; first and second interpole compensation winding circumferentially biased toward both sides respectively of said interpole core relative to a circumferential center of said interpole core; first and second brush members disposed on a commutation starting side and a commutation ending side of one of said brushes, respectively, for detecting a first voltage between said first brush member and said one brush when the segment of said commutator begins to contact with said first brush member, and a second voltage between said second brush member and said one brush when the segment of said commutator begins to leave from said second brush member; and a first current controller connected between said first brush member and said first interpole compensation winding, and a second current controller connected between said second brush member and said second interpole compensation winding, for controlling currents flowing through said first and second interpole compensation windings corresponding to said first and second voltages, respectively.