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:
Sep. 19, 2000
Filed:
Jun. 15, 1998
Hiroyasu Fujinaka, Yonago, JP;
Shigeru Otsuka, Yonago, JP;
Abstract
An inexpensive bearing unit having a high rotational accuracy and a high reliability is provided for use in information and video-acoustic equipments. In the case of an oil-impregnated sintered bearing (1) in which an inner surface (2) sliding together with a shaft is formed on the bearing body (1) made of a porous sintered alloy, a plurality of concavities (4) are transferred to a tapered portion of the bearing inner surface (2) by forming a part or the whole of the inner surface (2) into a tapered shape or a tapered-like shape at the time of molding a green compact of the sintered alloy and press-fitting a pin (5) formed with protrusions (6) in the subsequent process and moreover, concavities (7) in which the shaft sliding surface is closed are formed by sizing the tapered portion straight at the time of sizing. Because the concavities (7) making a superior dynamic-pressure effect can be formed in a simple process, it is possible to provide an inexpensive bearing unit having a high rotational accuracy.