To prevent leakage and scattering of oil particles for a long period, by providing an adhesive section which can maintain an adhesive property and elasticity for a long period between a sealing member and a sealing member attaching section, and sticking the sealing member to the sealing member attaching section with the adhesive section.

A sealing member 8 has an adhesive plate section 10 formed integrally with a cylindrical section 8 in addition to a cover section 23. The cylindrical section 9 is extended upward from the outer edge of the cover section 23 and the adhesive plate section 10 is formed at the upper end of the cylindrical section 9. The section 9 is press-fitted on the cylindrical neck section 42 of a rotor 5 in a fluid-tight structure and prevents the outward leakage or scattering of grease or oil particles in the radial direction. The annular flat surface 41 at the lower end of the rotor 5 is stuck to the adhesive plate section 10 with an adhesive section 11. An adhesive 50 which does not lose its elasticity for a long period is used as the adhesive section 11. Therefore, the contamination of a hard disk can be prevented.