An opening of a yoke provided to an electric motor is closed by a brush holder of an electricity supply unit. A pair of electricity supply terminals connected to respective brushes is fixed on the brush holder by outsert molding. A brush-side fixing pillar is inserted into a caulking hole piercing through a pigtail connecting portion of each electricity supply terminal, an input-side fixing pillar is inserted into a fixing hole piercing through an input-side connecting portion, and then the brush-side fixing pillar and the input-side fixing pillar are thermally caulked, whereby each electricity supply terminal is fixed on the brush holder. Each input-side fixing pillar and the corresponding brush-side fixing pillar, provided on the brush holder, are spaced away from each other by a predetermined distance so that a first terminal, a second terminal and a choke coil connected therebetween is attachable in place of the electricity supply terminal.

A carbon grounding brush has a sliding surface that slides on and grounds a driving shaft transmitting driving force and exposed to an insulating liquid. A slit is provided on the sliding surface, and at least one end of the slit is located on one side of the sliding surface. The slit introduces into the slit the insulating liquid pressed towards the sliding surface by the rotation of the driving shaft and discharges the insulating liquid from the one end of the slit. Thus, the contact resistance between the driving shaft and the sliding surface is made small, and electrical corrosion and electromagnetic noises are reduced.

A shunt for a charging contact assembly may include an elongate elastic support substrate and a conductor disposed of the elongate elastic support substrate for transferring electrical current. A charging contact assembly may include a connector to connect to a source of electrical energy for receiving electrical current and a brush coupled with the connector for contacting a conducting surface to transfer the electrical current. The charging contact assembly may also include a shunt fixedly connected to the connector and the brush for transferring the electrical current from the connector to the brush, where the shunt includes an elongate arcuate elastic support substrate fixedly connected to the connector and the brush, and a conductor disposed of the elongate arcuate elastic support substrate and extending between the connector and the brush.

A shunt for a charging contact assembly may include an elongate elastic support substrate and a conductor disposed of the elongate elastic support substrate for transferring electrical current. A charging contact assembly may include a connector to connect to a source of electrical energy for receiving electrical current and a brush coupled with the connector for contacting a conducting surface to transfer the electrical current. The charging contact assembly may also include a shunt fixedly connected to the connector and the brush for transferring the electrical current from the connector to the brush, where the shunt includes an elongate arcuate elastic support substrate fixedly connected to the connector and the brush, and a conductor disposed of the elongate arcuate elastic support substrate and extending between the connector and the brush.