Patent attributes
The invention provides a motor that is provided with a fluid dynamic bearing for rotatably supporting a shaft body, by the dynamic pressure of fluid filling a clearance between itself and a shaft body support part. The motor is provided with: a stator having cores and coils; a rotor having permanent magnets arranged in a ring shape on the radial inner side of the stator, facing the cores and coils; and a fluid dynamic bearing which rotatably supports the rotor with respect to the stator. The fluid dynamic bearing is provided with: a cylindrical shaft body whose cross section is approximately cruciform; a shaft body support part, in which a shaft body insertion hole is formed for accommodating the shaft body; and a fluid which is filled into a clearance formed between the shaft body and the shaft body insertion hole, and there is provided a dynamic pressure generation unit comprising the fluid, and dynamic pressure generating grooves formed in at least one of the outer face of the shaft body, and the inner face of the shaft body insertion hole facing this outer face.
