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:
Jun. 01, 2010
Filed:
Apr. 22, 2008
Seiji Sato, Iwata, JP;
Satoshi Kitano, Iwata, JP;
Yoshiaki Ryouno, Iwata, JP;
NTN Corporation, Osaka, JP;
Abstract
A chain tensioner includes a housing defining a cylinder chamber having a closed end. A cylindrical plunger having a closed front end is slidably received in the cylinder chamber. A nut member and a return spring are mounted in the cylinder chamber. The return spring biases the plunger outwardly of the housing to press its closed end against a pivotally supported chain guide. The nut member has a serration-shaped internal thread formed on the inner periphery thereof which is in threaded engagement with a serration-shaped external thread formed on the outer periphery of the screw rod. The screw rod is biased toward the closed end of the plunger by a rod spring. A damper is mounted between the front end of the screw rod and the closed front end of the plunger for damping, in cooperation with the return spring, a pushing force applied to the plunger, and for allowing the screw rod and the plunger to move relative to each other in a direction in which the distance between respective remote ends thereof decreases by an amount not less than an axial play present between the internal and external threads.