| 摘要 |
<p>PROBLEM TO BE SOLVED: To accurately detect the completion of invalid stroke narrowing of a clutch piston without being affected by an external element such as a variation in individual clutches.SOLUTION: In a circular-plate shape clutch piston 7, a ring groove 7A is formed; an in-piston oil passage 7B extending in a radial direction from an inner peripheral face is formed; and a penetration hole 7C penetrating the ring groove 7A from the in-piston oil passage 7B is formed. When clutch plates 5a, 5b are moved to an invalid stroke completion position being an engagement immediately-before position in association with the movement of the clutch piston 7, a motor disk spring 13 is crushed by loads from the clutch piston 7 side and the clutch plate 5a side, and the penetration hole 7C is closed. By this, the hydraulic pressure of a second in-cylinder oil passage 22A communicating with the in-piston oil passage 7B is lowered. By detecting the lowering of the hydraulic pressure by a hydraulic pressure switch 120, the completion of invalid stroke of the clutch piston 7 is detected.</p> |
