US 6,888,285 B2 · Dynamo-electric machine and fan motor for vehicle

Abstract

An electric rotating machine and a fan motor for vehicle are obtained, wherein variation width of current waveform resulting from occurrence of coils in a short circuit state is narrowed to reduce vibration and noise. A commutator 26 of the fan motor for vehicle comprises twelve segments 24, and a pair of positive/negative brushes are press-contacted to the commutator 26. Among the segments 24, at least one of pairs of segments that the brushes simultaneously contact have mutually different pitches. Therefore, timing when the coil in the short circuit state occurs at an armature and timing when the coil is released from the short circuit state of one brush deviate from those of the other brush temporally. Accordingly, the variation width of current waveform of electric current supplied to the coil connected to the pair of segments 24 narrows at least. As a result, the vibration of the electric rotating machine, variation of rotating torque, and the noise are considerably reduced, and life thereof is thus extended as well.

Claims20

Dependent claims

An electric rotating machine comprising:

a motor yoke;
a field magnet fixed inside the motor yoke;
an armature comprising a rotating shaft at a central portion of a laminated core on which windings are wound, wherein a commutator comprising a plurality of segments, in which at least one pair of segments comprise mutually different peripheral widths, is attached to an end portion of the rotating shaft;
and
a plurality of brushes disposed opposite each other with the commutator therebetween, so as to slide on the commutator of the armature.

2 more elements

A fan motor for vehicle comprising:

a motor yoke;
a field magnet fixed inside the motor yoke;
an armature comprising a rotating shaft at a central portion of a laminated core on which windings are wound, wherein a commutator comprising a plurality of segments, in which at least one pair of segments comprise mutually different peripheral widths, is attached to an end portion of the rotating shaft;
a plurality of brushes disposed opposite each other with the commutator therebetween, so as to slide on the commutator of the armature;
and
a fan attached to the rotating shaft so as to rotate as the armature rotates.

3 more elements

Dependencies are inferred from the claim text.

Dynamo-electric machine and fan motor for vehicle

Life of this patent

Dynamo-electric machine and fan motor for vehicle

Life of this patent

Abstract

Claims20