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:
May. 08, 1990
Filed:
Jan. 24, 1989
Takashi Mizukusa, Aichi, JP;
Juzo Yagi, Aichi, JP;
NGK Spark Plug Co., Ltd., Nagoya, JP;
Abstract
A rotary valve made of ceramics has edges at the junctions between a generally cylindrical outer periphery and opposite ends of a through hole. Each of the edges has a leading edge portion at which the valve starts opening and a leading edge portion at which the valve finishes closing. The leading edge portions are chamferred in such a way as to form part of surfaces of right circular cones whose vertexes are contained in an axis of rotation of the rotary valve and whose axes coincide with the center axis of the through hole.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile