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:
Oct. 18, 1994
Filed:
May. 06, 1993
Shinichi Minakuchi, Iyo, JP;
Nobuhiro Yoshino, Oozu, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A motor having a dynamic-pressure type bearing device includes a cylindrical sleeve fixedly secured to a base, a shaft rotatably inserted into a hollow of the cylindrical sleeve, a hub fixedly secured to an end portion of the shaft, a ring-like rotor magnet fixedly secured to the hub, and an armature fixedly secured onto the base to be in opposed relation to the rotor magnet so as to constitute a motor driving device. Further, the motor has a disc-like plate coaxially and fixedly secured to an end portion of the shaft to have a diameter of the disc-like plate greater than a diameter of the shaft and a plate disposed in opposed relation to a surface of the disc-like plate. The bearing device includes a radial dynamic-pressure groove assembly having a predetermined groove configuration to generate a radial dynamic pressure in a radial direction of the shaft and an axial dynamic-pressure groove assembly having a predetermined groove configuration to generate an axial dynamic pressure in an axial direction of the shaft. The radial dynamic-pressure groove assembly is formed in at least one of an outer circumferential surface of the shaft and an inner surface of the cylindrical sleeve which face each other and the axial dynamic-pressure groove assembly is formed in at least one of the surface of the disc-like plate and a surface of the plate disposed in opposed relation to the surface of the disc-like plate.