Abstract: A differential amplifier includes a first input terminal, second input terminals, output terminals, differential amplification circuits, and a current source circuit. The first input terminal is one of an inverting input terminal and a non-inverting input terminal. Each of the second input terminals is another of the inverting input terminal and the non-inverting input terminal. The output terminals output voltages respectively corresponding to the second input terminals. The differential amplification circuits are connected to the first input terminal and the second input terminals and are provided corresponding to the second input terminals. The current source circuit is connected to the differential amplification circuits. Each of the differential amplification circuits outputs an output voltage corresponding to a combination of a voltage inputted to the first input terminal and a voltage inputted to one of the second input terminals from a corresponding one of the output terminals.

Abstract: A bearing structure includes a bearing and a housing. The bearing rotationally supports a rotation shaft extending in an axial direction. The bearing includes an outer circumferential surface having an arcuate surface that projects outward in a radial direction from an axial end toward a middle portion of the axial direction. The housing includes a bearing accommodation recess that extends in the axial direction to accommodate and hold the bearing. The bearing accommodation recess includes an inner circumferential surface including a cylindrical portion and an abutment portion. The bearing is located at an inner side of the cylindrical portion. The abutment portion partially projects radially inward from the cylindrical portion. The arcuate surface of the bearing abuts against the abutment portion at least at three locations that are separated from one another in a rotation direction of the rotation shaft.

Abstract: A brush holder is held between a flange of a yoke housing and a gear housing of a speed reduction unit and fastened by a fastening screw. A link of the brush holder is located between a screw fastening portion of the flange and a screw fastening portion of the gear housing. A connector is linked to a holder main body by the link. The link includes a screw insertion hole and first and second bridges. A metal terminal, which electrically connects the holder main body and the connector, is embedded in each of the first and second bridges.

Abstract: A bearing structure includes a bearing and a housing. The bearing rotationally supports a rotation shaft extending in an axial direction. The bearing includes an outer circumferential surface having an arcuate surface that projects outward in a radial direction from an axial end toward a middle portion of the axial direction. The housing includes a bearing accommodation recess that extends in the axial direction to accommodate and hold the bearing. The bearing accommodation recess includes an inner circumferential surface including a cylindrical portion and an abutment portion. The bearing is located at an inner side of the cylindrical portion. The abutment portion partially projects radially inward from the cylindrical portion. The arcuate surface of the bearing abuts against the abutment portion at least at three locations that are separated from one another in a rotation direction of the rotation shaft.

Abstract: A brush holder is held between a flange of a yoke housing and a gear housing of a speed reduction unit and fastened by a fastening screw. A link of the brush holder is located between a screw fastening portion of the flange and a screw fastening portion of the gear housing. A connector is linked to a holder main body by the link. The link includes a screw insertion hole and first and second bridges. A metal terminal, which electrically connects the holder main body and the connector, is embedded in each of the first and second bridges.