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:
Mar. 30, 2021
Filed:
Dec. 06, 2016
Nok Corporation, Tokyo, JP;
Takayuki Oyama, Fujisawa, JP;
Nobuhiro Nishimura, Fukushima, JP;
Hiroshi Onodera, Fukushima, JP;
Masamichi Kishiro, Fukushima, JP;
NOK CORPORATION, Tokyo, JP;
Abstract
A valve stem seal with significantly improved sealing performance while improving workability when fitting the valve stem seal to a valve stem guide. An inner peripheral surface of a fitting sectionB is provided with a plurality of annular seal protrusions which respectively include first inclined surfacesandeach having a diameter that increases from a radially inward tip toward a seal sectionA side, and second inclined surfacesandeach having a diameter that increases from a radially inward tip toward a side opposite to the seal sectionA. The first seal protrusionwhich is closest to the seal sectionA is configured so that an inclination of the second inclined surfaceis smaller than that of the first inclined surface, and the second seal protrusionwhich is farthest from the seal sectionA is configured so that an inclination of the first inclined surfaceis smaller than that of the second inclined surface