Patent ID: 8167749
Filing Date: 2012-05-01
Classification: F16H

Abstract:
1. A belt tensioner, comprising: a bearing case attached to an end face of an engine body; a tensioner arm, a base end portion of which is supported rotatably at the bearing case via an axis in parallel to an engine output shaft; a pulley supported rotatably at a free end portion of the tensioner arm via an axis in parallel to the engine output shaft; and a biasing mechanism provided between the bearing case and the tensioner arm so as to bias the tensioner arm toward a belt, wherein the tensioner arm comprises a tool-engagement portion for engaging with a tensioner-arm rotation tool, and a jig-holding portion which has a through hole for accepting a tensioner-arm fixation bar jig inserted thereinto from above at a portion of the tensioner arm extending upward from the base end portion, and the bearing case comprises a contact face portion which is provided at a face located below the jig-holding portion of the bearing case so as to accept the bar jig inserted into the through hole of the tensioner arm, and an engagement stair portion which is provided at the contact face portion so as to engage with the bar jig such that a move of the tensioner arm toward the belt by the biasing mechanism is restricted.