Motor

摘要

A motor which includes: inner ring having upper end surface, outer ring, and balls between inner ring and outer ring. Pressurizing spring, into which rotary shaft is inserted, is located between core and bearing, and provides bias forces in the axial direction of rotary shaft. Outer ring is pressed to fit into bearing holding part. Inner ring is fitted onto rotary shaft with gap therebetween. Upper end surface of inner ring is in contact with pressurizing spring. Pressurizing spring applies the bias forces of different strengths onto a surface in which upper end surface contacts with pressurizing spring, along a circumferential direction with the axial direction as a center.

主权项

1. A motor comprising:
a rotor including:
a core; anda rotary shaft fixed to the core, the rotary shaft having an axial center thereof that coincides with an axial center of the core; a bearing including:
an inner ring having an upper end surface in a direction toward a location of the core;an outer ring; andballs between the inner ring and the outer ring; a pressurizing spring, into which the rotary shaft is inserted, located between the core and the bearing, for applying a bias force in an axial direction of the rotary shaft; and a yoke including a bearing holding part to hold the bearing, and rotatably holding the rotor via the bearing, wherein the outer ring is pressed to fit into the bearing holding part; the inner ring is fitted onto the rotary shaft with a gap therebetween, the upper end surface of the inner ring being in contact with the pressurizing spring; and the pressurizing spring applies the bias forces of different strengths onto a contact surface of the upper end surface being in contact with the pressurizing spring, along a circumferential direction with the axial direction as a center, and wherein the core includes a lower end surface in a direction toward a location of the bearing; the pressurizing spring includes:
an inner-ring portion having a bearing-side surface in contact with the upper end surface;an outer-ring portion having a core-side surface in contact with the lower end surface; anda plurality of connecting portions each having an elastic force and coupling the inner-ring portion with the outer-ring portion, the inner-ring portion is coupled with the plurality of connecting portions at a plurality of inner-side connecting positions, respectively, and the outer-ring portion is coupled with the plurality of connecting portions at a plurality of outer-side connecting positions, respectively, and wherein the elastic force of at least one of the plurality of the connecting portions is different in strength from the elastic forces of the other connecting portions.