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:
Aug. 17, 2010
Filed:
Jun. 28, 2005
Seiji Sato, Iwata, JP;
Satoshi Kitano, Iwata, JP;
Hisashi Hayakawa, Iwata, JP;
NTN Corporation, Osaka, JP;
Abstract
A chain tensioner for use with a chain of a vehicle engine, includes a housing and a plunger slidably mounted in a cylinder chamber formed in the housing. The plunger is biased outwardly by a return spring mounted in a pressure chamber defined in the cylinder chamber by the plunger. A check valve is provided in the cylinder chamber to prevent backflow of hydraulic oil in the pressure chamber. A relief valve, provided in the plunger, opens above a relief pressure, thereby discharging hydraulic oil in the pressure chamber. An oil leakage clearance is defined between the plunger and the inner wall of the cylinder chamber. The relief pressure and the oil leakage clearance dimension are determined such that the tension in the chain is kept at such a level that vibrations of the chain are minimum at any temperature of hydraulic oil and at any engine revolution speed.