Patent ID: 7663286
Filing Date: 2010-02-16
Classification: H01R,H02K

Abstract:
1. A motor comprising: a rotor; a commutator that has a rectifying surface for rectifying an electric current supplied to the rotor, the commutator being constructed of multiple segments that are circumferentially divided; a brush that repeatedly makes contact with each segment of the commutator via the rectifying surface of the commutator and conducts the electric current when the rotor and the commutator rotate relative to the brush along a rotative direction, the brush initially making each said contact with each segment of the commutator on an entry side of the brush when the rotor and the commutator rotate with respect to the brush along the rotative direction; a bias member that biases the brush; and a housing member in which the brush is axially slidable, wherein the brush has a first brush end on a side of the commutator, the brush has a second brush end at an opposite end of the brush with respect to the commutator, the second brush end having a slant surface, an axial length on the entry side is greater than an axial length on an opposite side of the brush from the entry side, with respect to the rotative direction, the bias member is in contact with the slant surface of the brush and applies bias force to the slant surface toward the entry side along a line of action, the housing member defining a gap with the brush in the rotative direction to enable the brush to incline within the gap, the line of action intersects the rectifying surface at an intersection which is located on the entry side and outside of the brush, the brush has an entry side first corner, which is on the entry side at the first brush end and makes contact with the rectifying surface, and an entry side second corner, which is on the entry side at the second brush end, the brush is enabled to incline around the entry side first corner, the brush is in contact with an inner wall of the housing member at the entry side second corner when the brush inclines, the brush further has a contact portion, which is on an opposite side of the brush from the entry side with respect to the rotative direction and is in contact with an inner wall of the housing member, the brush is supported at the entry side first corner, the entry side second corner, and the contact portion, and the bias member applies bias force to the brush at an angle relative to the rectifying surface to incline the brush so that the housing supports the brush at the entry side second corner and so that the contact portion is in line contact with the housing.