Hydrodynamic bearing

A hydrodynamic bearing comprising:

• a cylindrical radial bearing member having an outer circumferential surface;
• first and second thrust plates held against the respective axially opposite ends of said cylindrical radial bearing member, said first and second thrust plates having confronting surfaces, respectively;
• a cylindrical radial sleeve having an inner circumferential surface facing said outer circumferential surface of said cylindrical radial bearing member, and a pair of axially opposite end surfaces facing said confronting surfaces, respectively, of said first and second thrust plates;
• wherein
• said outer circumferential surface of said cylindrical radial bearing member and said inner circumferential surface of said cylindrical radial sleeve serving as sliding surfaces jointly making up a radial hydrodynamic bearing assembly;
• said confronting surfaces of said first and second thrust plates and said end surfaces of said cylindrical radial sleeve serving as sliding surfaces jointly making up a thrust hydrodynamic bearing assembly;
• at least one of said sliding surfaces of said thrust hydrodynamic bearing assembly having grooves formed therein for generating a hydrodynamic pressure;
• at least one of the sliding surfaces of said radial hydrodynamic bearing assembly being coated with a uniform hydrogenated amorphous carbon film;
• and
• at least one of the sliding surfaces of said thrust hydrodynamic bearing assembly being coated with a uniform hydrogenated amorphous carbon film.