| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a hydraulic auto tensioner wherein the fall-off of a vent is prevented. <P>SOLUTION: A rod 14 is inserted into a sleeve 13 of a cylinder 11 to form a pressure chamber 15, and the thrust of a return spring 19 is imparted to a spring seat 18 at the upper part of the rod 14. A bellows 22 is provided between the outer periphery of the spring seat 18 and the upper part of the cylinder 11 to form a reservoir chamber 23, and a check valve 25 is provided in a first oil passage 24 between the reservoir chamber 23 and the pressure chamber 15. When pushing force is loaded on the cylinder 11 and the rod 14 in their contracting directions, the check valve 25 closes the first oil passage 24 and operating oil in the pressure chamber 15 absorbs the shock of the pushing force. The spring seat 18 has a vent incorporating hole 41 for incorporating the vent 44 and a vent path 42 for communicating the vent incorporating hole 41 with the reservoir chamber 23 so that outside air flows into/out of the reservoir chamber 23 with a pressure change of the reservoir chamber 23. A vent come-off preventing means 50 is provided between the vent incorporating hole 41 and the vent 44. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
