A carbonaceous material is fabricated by kneading of carbon powder and a binder. The carbonaceous material is granulated such that an average particle diameter of the carbonaceous material is 0.3 mm or more. A brush material is fabricated by mixing of the granulated carbonaceous material and metallic powder. A ratio of the metallic powder to a total weight of the brush material is adjusted to 1% by weight or more and 30% by weight or less. Pressure molding is performed on the fabricated brush material, and thermal processing is further performed on the brush material at a temperature at which a resin in the brush material is not carbonized.

A carbonaceous material is fabricated by kneading of carbon powder and a binder. The carbonaceous material is granulated such that an average particle diameter of the carbonaceous material is 0.3 mm or more. A brush material is fabricated by mixing of the granulated carbonaceous material and metallic powder. A ratio of the metallic powder to a total weight of the brush material is adjusted to 1% by weight or more and 30% by weight or less. Pressure molding is performed on the fabricated brush material, and thermal processing is further performed on the brush material at a temperature at which a resin in the brush material is not carbonized.

A rotor assembly includes a rotor shaft and a rotor core supported by the rotor shaft and surrounded by a plurality of windings. The rotor assembly also includes a first brush engaging a first slip ring fixed relative to a first distal end of the rotor shaft. The first brush includes one of a first conical projection or a first convex receptacle and the first slip ring includes the other of the first conical projection or the first convex receptacle. A first electrical connection extends between the first slip ring and the plurality of windings. A second brush is configured to engage a second slip ring with the second slip ring fixed relative to the rotor shaft. A second electrical connection extending between the second slip ring and the plurality of windings.

A rotor assembly includes a rotor shaft and a rotor core supported by the rotor shaft and surrounded by a plurality of windings. The rotor assembly also includes a first brush engaging a first slip ring fixed relative to a first distal end of the rotor shaft. The first brush includes one of a first conical projection or a first convex receptacle and the first slip ring includes the other of the first conical projection or the first convex receptacle. A first electrical connection extends between the first slip ring and the plurality of windings. A second brush is configured to engage a second slip ring with the second slip ring fixed relative to the rotor shaft. A second electrical connection extending between the second slip ring and the plurality of windings.

The present disclosure relates to a motor with bidirectional terminals. According to the present disclosure, as the brush terminals are installed on both the left and right sides of the upper surface of the brush card assembly, it is possible to prevent the assembly defects of the motor due to the erroneous assembly of the brush terminals.

The present disclosure relates to a motor with bidirectional terminals. According to the present disclosure, as the brush terminals are installed on both the left and right sides of the upper surface of the brush card assembly, it is possible to prevent the assembly defects of the motor due to the erroneous assembly of the brush terminals.

A power transmission device for energizing an electrical winding carried by a rotor of an electric machine is disclosed, and may include a slip ring unit, at least one slip ring non-rotatably fastened to the slip ring unit, a brush unit, and at least two brushes held on the brush unit for parallel energization of the slip ring. The at least one slip ring may be configured to be electrically connected to the winding. The brushes may be held on the brush unit such that the brushes may touch the slip ring an establish an electrical contact via a contact surface. When the slip ring unit rotates, the brushes may sweep over a running surface on the slip ring The brushes may be configured such that the respective running surfaces on the slip ring do not overlap. An electric machine with such a power transmission device is also disclosed.

A power transmission device for energizing an electrical winding carried by a rotor of an electric machine is disclosed, and may include a slip ring unit, at least one slip ring non-rotatably fastened to the slip ring unit, a brush unit, and at least two brushes held on the brush unit for parallel energization of the slip ring. The at least one slip ring may be configured to be electrically connected to the winding. The brushes may be held on the brush unit such that the brushes may touch the slip ring an establish an electrical contact via a contact surface. When the slip ring unit rotates, the brushes may sweep over a running surface on the slip ring The brushes may be configured such that the respective running surfaces on the slip ring do not overlap. An electric machine with such a power transmission device is also disclosed.

A system for monitoring the wear state of a carbon brush of a brush holder assembly in which the length of the carbon brush is diminished from an initial length as an end of the carbon brush wears away during use. The system includes a wear state monitor, including a sensor, coupled to the carbon brush. The wear state monitor is configured to rotate as the length of the carbon brush diminishes. The sensor is configured to measure an angular displacement of the wear state monitor as the wear state monitor rotates. The measured angular displacement of the wear state monitor correlates to an amount of diminution in the length of the carbon brush.

A system for monitoring the wear state of a carbon brush of a brush holder assembly in which the length of the carbon brush is diminished from an initial length as an end of the carbon brush wears away during use. The system includes a wear state monitor, including a sensor, coupled to the carbon brush. The wear state monitor is configured to rotate as the length of the carbon brush diminishes. The sensor is configured to measure an angular displacement of the wear state monitor as the wear state monitor rotates. The measured angular displacement of the wear state monitor correlates to an amount of diminution in the length of the carbon brush.