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:
Dec. 30, 2003
Filed:
Oct. 06, 2000
Shigeharu Sumi, Shigaken, JP;
Nidec Corporation, Kyoto, JP;
Abstract
A fluid seal is disposed in a radial gap between a shaft of a motor and a hub rotatably held about the shaft, for preventing contaminates such as oil dusts and the like within the motor from leaking to the outside of the motor. The fluid seal has an annular body disposed about the axis of the motor shaft that is fixed to the hub directly or with a fluid seal holder. The annular sealing surface of the annular body is spaced from the outer sealing surface of the shaft by a minute gap, and a sealing portion is formed in the gap. The gap is filled with a fluid having a sufficient barrier pressure to prevent contaminates from flowing out of the motor. The fluid seal may have an approximately concave shape facing the axis of the shaft when the shaft is cut away by a plane passing through the axis of the shaft. This structure prevents the fluid from being scattered due to centrifugal force arising during operation of the motor. The fluid seal also may have an angled seal structure to keep the fluid in against external shocks. A fluid seal built-into a ball bearing is also disclosed.