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. 14, 2019
Filed:
Dec. 17, 2014
Nippon Piston Ring Co., Ltd., Saitama, JP;
Nittan Valve Co., Ltd., Kanagawa, JP;
Satoshi Ikemi, Tochigi, JP;
Hiroshi Oshige, Tochigi, JP;
Kiyoshi Suwa, Tochigi, JP;
Kenichi Sato, Tochigi, JP;
Kouji Kunitake, Kanagawa, JP;
Ryouichi Yoshino, Kanagawa, JP;
NIPPON PISTON RING CO., LTD., Saitama, JP;
NITTAN VALVE CO., LTD., Kanagawa, JP;
Abstract
In an assembly of a hollow poppet valve and a valve seat insert, the hollow poppet valve's head is integrally formed with a stem end, a hollow part is formed from the head to a stem, and coolant is filled into the hollow part along with an inert gas. The valve seat insert is formed of iron base sintered alloy and obtained by integrating two layers of a supporting material side layer and a valve contact face side layer. The hollow poppet valve is formed of a material having thermal conductivity of 5-45 (W/m·K) at 20-1000° C. The valve seat insert includes the supporting material side layer having thermal conductivity of 23-50 (W/m·K) at 20-300° C. and a valve contact face side layer having thermal conductivity of 10-22 (W/m·K) at 20-300° C. This enables a valve temperature decrease throughout an engine's entire RPM range compared with the prior art.