Patent ID: 9285019
Filing Date: 2016-03-15
CPC Classification: F02B,F16H

Claim Text:
1. A chain transmission device for driving a camshaft, comprising: a driving sprocket mounted to a crankshaft; a driven sprocket mounted to a camshaft; a timing chain looped over the driving sprocket and the driven sprocket; a pivotable chain guide provided on one side of a slack side of the timing chain, and retaining a plurality of rotatable rollers for guiding movements of the timing chain so as to be spaced from each other in a direction in which the timing chain is moved; and a chain tensioner for applying an adjustment force to a remote end of the pivotable chain guide remote from a center of pivoting movement of the pivotable chain guide, thereby pressing the plurality of rotatable rollers against the timing chain, wherein the driving sprocket and the plurality of rotatable rollers are designed such that a ratio (D wherein each of the plurality of rotatable rollers is a roller bearing including a shell-shaped outer race which is formed by drawing a thick metal plate having a thickness of 1 mm to 3 mm and has inwardly extending flanges at both ends thereof, a plurality of roller elements received in the shell-shaped outer race, and a retainer for retaining the plurality of roller elements, and wherein the shell-shaped outer race contacts and guides the timing chain.