| 摘要 |
PURPOSE:To completely protecting the case-side part of an oil seal of a push rod which projected outside of a case, from being swelled with oil in a hydraulic cylinder by providing the oil seal for a cover. CONSTITUTION:A push rod 4 has the end part 4a thereof engaged with a clutch 6 and has the other end 4b thereof projected at the outside of a case 2 in an oil- tight manner via an oil seal 7. At the outside of the push rod 4 a hydraulic cylinder 10 making contact therewith is disposed so that a clutch 6 can be pushed to be disengaged via a rod 4 by the operation of a cylinder 10. The cylinder 10 has a surrounding wall 11 surrounding the periphery of said end part 4b and an oil seal 7 is provided on the bottom face of the surrounding wall 11 in such a manner as to be engaged in a seal hole 7a. An annular groove 14 is formed on the external periphery of the surrounding wall 11 and the seal 7 is displaced inside the seal hole 7a in the slightly inward direction thereof. |
