Patent ID: 7567007

Claim:
A motor comprising: an armature a plurality of slots provided on the armature in the circumferential direction around an axis of the armature, a commutator that rotates together with the armature, a plurality of segments provided on the commutator in the circumferential direction around the axis of the commutator and an armature winding having at least a first and a second unit windings formed between the armature and the segments, wherein: the first unit winding is defined by a first, a second and a third segments of the plurality of the segments, a coil of a first group and a coil of a second group for the first unit winding which are formed by winding the wire around respectively predetermined slot groups of slots selected from the plurality of the slots, and a first equalizing wire, the first segment defines a starting point of the first unit winding, the coil of the first group for the first unit winding and the coil of the second group for the first unit winding are connected in series in this order by winding the wire from the first segment to the second segment, the first equalizing wire is connected from the second segment to the third segment that defines an endpoint of the first unit winding, the second unit winding is defined by a third, a fourth and a fifth segments of the plurality of the segments, a coil of a first group and a coil of a second group for the second unit winding, and a second equalizing wire, the coils of the first and the second groups of the second unit winding being formed by winding the wire around respectively predetermined slot groups of slots which are selected from the plurality of the slots in such a manner as to include some of the slots of the slot groups used to form the coils of the first and the second groups of the first unit winding, the coils of the first and the second groups for the second unit winding being disposed in a position shifted from the coils of the first and the second groups for the first unit winding in the circumferential direction around the axis of the armature, the third segment defines an endpoint of the first unit winding and also defines a starting point of the second unit winding, the coil of the second group for the second unit winding and the coil of the first group for the second unit winding are connected in series in this order by winding the wire from the third segment to the fourth segment, the second equalizing wire is connected from the fourth segment to the fifth segment that defines an endpoint of the second unit winding, and wherein the first and the second unit windings are provided in which the groups of coils in one unit winding are connected from a starting-point segment to an endpoint segment in a different order from the group of coils in the other unit winding such that the wires connected between the commutator and the armature is prevented from regularly overlapping each other so as to avoid imbalance due to the increased wire volume.