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. 16, 2000
Filed:
Nov. 09, 1998
Tadasu Suzuki, Tokyo-to, JP;
Junya Kurohata, Saitama-ken, JP;
Tsubakimoto Chain Co., Osaka, JP;
Abstract
A backlashless ratchet-type tensioner includes a tensioner housing, a plunger slidably fitted into a plunger accommodation bore formed in the tensioner housing and urged by a spring such that a tip portion of the plunger is projected to the exterior of the plunger accommodation bore, and a ratchet pivotally supported on a ratchet pin provided on the tensioner housing. At least one ratchet pawl formed on the ratchet is meshed with rack teeth formed on an outer surface of the plunger so as to prevent the plunger from receding into the plunger accommodation bore. A front face of the ratchet pawl is formed substantially perpendicular to a straight line which passes through a tip of the ratchet pawl and the center of the ratchet pin. The angle between a plane perpendicular to the axis of the plunger and the front face of the ratchet pawl meshed with a rack tooth is slightly smaller than the angle between the plane perpendicular to the axis of the plunger and a rear face of the rack tooth. When the ratchet pawl comes into engagement with a rack tooth, the tip end of the ratchet pawl pushes the rear face of the rack tooth to slightly advance the plunger and hold it in a backlash-eliminated state.