Abstract: A reduction gear configured to decelerate and output rotation of a motor includes two-stage planetary gear mechanisms that are provided side by side in an axial direction of the motor and are each configured of helical gears, and a case made of resin and formed into a cylindrical shape, the case incorporating the two-stage planetary gear mechanisms. At least one of an inner engagement ratio of a sun gear and a pinion gear of the planetary gear mechanism in a first stage and an outer engagement ratio of the pinion gear and a ring gear of the planetary gear mechanism in the first stage is 3.0 or more, and both the inner engagement ratio and the outer engagement ratio are larger than an engagement ratio of the planetary gear mechanism in a second stage.

Abstract: A reduction gear configured to decelerate and output rotation of a motor by two-stage planetary gear mechanisms disposed side by side in an axial direction includes: a case made of resin, the case being formed into a cylindrical shape in which the two-stage planetary gear mechanisms are incorporated, and having at least one of a lid portion and a bottom portion provided at each of both axial ends; and a reinforcing component that is formed of a material having a Young's modulus higher than a Young's modulus of a material of the case. The reinforcing component extends along at least a part of an inner peripheral surface in an axial central portion of the case.

Abstract: A reduction gear configured to decelerate and output rotation of a motor by two-stage planetary gear mechanisms disposed side by side in an axial direction includes: a case made of resin, the case being formed into a cylindrical shape in which the two-stage planetary gear mechanisms are incorporated, and having at least one of a lid portion and a bottom portion provided at each of both axial ends; and a reinforcing component that is formed of a material having a Young's modulus higher than a Young's modulus of a material of the case. The reinforcing component extends along at least a part of an inner peripheral surface in an axial central portion of the case.

Abstract: A reduction gear configured to decelerate and output rotation of a motor includes two-stage planetary gear mechanisms that are provided side by side in an axial direction of the motor and are each configured of helical gears, and a case made of resin and formed into a cylindrical shape, the case incorporating the two-stage planetary gear mechanisms. At least one of an inner engagement ratio of a sun gear and a pinion gear of the planetary gear mechanism in a first stage and an outer engagement ratio of the pinion gear and a ring gear of the planetary gear mechanism in the first stage is 3.0 or more, and both the inner engagement ratio and the outer engagement ratio are larger than an engagement ratio of the planetary gear mechanism in a second stage.

Abstract: A flat type commutator is provided which secures fixing of carbon (graphite) commutator pieces to both metal plates with terminals attached thereto for connecting winding and electrically insulating support, and which can be manufactured easily and at a low manufacturing cost. The flat type commutator has a brush slide-contact surface which is perpendicular to the axial direction of a rotor, wherein a plurality of commutator pieces (3), which are mutually isolated by slits (4), are directly fixed to an electrically insulating support (1), and a metal plate (5) for connecting the commutator pieces, each having terminals (6) for connecting windings is fixed on the outer peripheral surface of each commutator piece (3) which is parallel with the axial direction of the rotor.

Abstract: There is provided a flat type commutator which secures fixing of carbon (graphite) commutator pieces to both metal plate with terminals attached thereto for connecting winding and electrically insulating support, and which can be manufactured easily and at a low manufacturing cost.A flat type commutator with the brush slide-contact surface thereof being perpendicular to the axial direction of a rotor, wherein a plurality of commutator pieces 3 mutually isolated by slits 4 are directly fixed to an electrically insulating support 1, and a metal plate 5 for connecting said commutator pieces, each having terminals 6 for connecting windings is fixed on the outer peripheral surface of said each commutator piece 3 which is in parallel with the axial direction of the rotor.