| 摘要 |
PROBLEM TO BE SOLVED: To automatically return a phase of a camshaft to an intermediate position by utilizing a fluctuation torque acting on the camshaft to thereby lock a valve timing controller without backlash. SOLUTION: Parallel guide portions 3a integral with a sprocket 1 and inclined guide portions 7a integral with a vane 6 are alternately arranged on the same circumference. The inclined guide portions are so formed that circumferential gaps between the inclined guide portions and the parallel guide portions become smaller in one direction of the camshaft. Wedge members 16, 17 are arranged in the respective circumferential gaps. By moving the wedge members in one direction of the camshaft, the circumferential gaps are plugged so as to secure the phase between the sprocket and the vane, thereby bringing the valve timing controller into a locked state. At that time, the wedge members having wedge angles set at sufficiently small values are energized by springs 15. The wedge members are moved in one direction of the camshaft by being energized by the springs while utilizing the positive and negative fluctuation torque acting on the camshaft so as to lock the valve timing controller. Further, the wedge members are hydraulically driven in a direction opposite to one direction of the shaft so as to release the valve timing controller from the locked state, thereby enabling control of the phase angle. COPYRIGHT: (C)2007,JPO&INPIT
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