CHAIN TRANSMISSION DEVICE FOR DRIVING CAMSHAFTS

摘要

A chain transmission device for driving camshafts is provided, the device including a chain including a loose side chain portion, and trained around the crank sprocket and the cam sprockets, and a chain guide mounted on the outer side of the loose side chain portion so as to be pivotable about one of the two end portions of the chain guide, and provided with a plurality of rotatable rollers. An adjustment force is applied to the other of the two end portions of the chain guide by a chain tensioner such that the chain guide is biased toward the chain, so that the rollers of the chain guide can guide the chain by rolling. The winding angle of the portion of the chain located on the outer periphery of the roller located closest to the crank sprocket is set to be 170 degrees or over so as to reduce noise.

主权项

1. A chain transmission device for driving a camshaft, the device comprising:
a crank sprocket mounted to a crankshaft; a cam sprocket mounted to the camshaft; a chain including a loose side chain portion, and trained around the crank sprocket and the cam sprocket; and a chain guide mounted on an outer side of the loose side chain portion so as to be pivotable about one of two end portions of the chain guide, and provided with a plurality of rotatable rollers, wherein an adjustment force is applied to the other of the two end portions of the chain guide by a chain tensioner such that the chain guide is biased toward the chain, so that the rollers of the chain guide can guide the chain by rolling, wherein one of the rollers is located closest to the crank sprocket, and a winding angle of a portion of the chain located on an outer periphery of said one of the rollers is set to be 170 degrees or over.