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. 27, 1988
Filed:
Oct. 31, 1986
Applicant:
Inventors:
Assignee:
Ebara Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01D / ;
U.S. Cl.
CPC ...
324175 ; 384448 ; 2502 / ; 34087002 ;
Abstract
A thrust bearing contructed to comprise a pair of disc elements one of which is arranged to rotate and the other of which is kept stationary, the surface of the rotating side opposing the stationary element being provided with a pattern of spiral grooves which are non-reflective while the remaining lands of the pattern are reflective so that a pulsed light beam is reflected from the pattern when a light beam is directed onto the rotating pattern through a hole provided in the stationary element, the reflected light pulses being utilized for determining the rotational speed of the element under rotation.