DEVICE FOR HYDRAULICALLY ADJUSTING ROTATION ANGLE OF SHAFT WITH RESPECT TO DRIVING PULLEY

摘要

PROBLEM TO BE SOLVED: To surely fix an inside wheel or a shaft with respect to a capacity wheel at each rotational position for the prevention of unfavorable position change during driving 1, by providing a ring piston as means for fixing the rotational position, and contacting this ring piston with at least one end face of a vane or a capacity wheel. SOLUTION: A device for hydraulically adjusting a rotational angle of a cam shaft 1 of an internal combustion engine with respect to a driving pulley 18 has an inside portion 14 non-rotatably connected to the cam shaft 1. The inside portion 14 is provided with four vanes which extend in at least substantially radial direction. The pulley 18 is provided with four vanes distributed along an entire circumference thereof. The outside and inside vanes divide the inside of a capacity chamber into a plurality of pressure chambers. An end face of each vane opposite from a shaft end portion and an area of an edge portion 20 extending up to an inner periphery surface of a ring shaped extended portion 26 are made into flat surfaces. A disc 28 as a ring piston is contacted with the flat surfaces to fix the rotational position of the inside portion with respect to the pulley 18.