The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 24, 2008
Filed:
Jan. 03, 2006
Takeyoshi Yamamoto, Niihama, JP;
Takeyoshi Yamamoto, Niihama, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A spindle motor which allows appropriate formation of communicating hole for compensating a pressure difference due to an error in working of dynamic pressure generating grooves and other components, easy formation of dynamic pressure generating grooves and readily prevention of leakage of a lubrication fluid is provided. An outer cylindrical member is attached to a shaft, a radial hydrodynamic bearing and a thrust hydrodynamic bearing are provided between the outer cylindrical member and the sleeve, and communicating holes are formed between the shaft and the outer cylindrical member, and between the hub and the outer cylindrical member. Since the collared outer cylindrical member is attached to the shaft, the communicating holes can be readily formed. Also, since a thrust hydrodynamic bearing is formed between an opening of a communicating hole and a seal, a lubrication fluid is unlikely to leak from the seal portion. The outer cylindrical member having the collar portion also enables easy formation of a thrust dynamic pressure generating groove, using inexpensive methods such as pressing.