| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a hydraulic tensioner, in which stiction of a check ball on a seat surface of a ball seat is suppressed in a check valve unit to enable improvement of valve opening performance of the check ball and reduction of noise due to fluttering of a chain, and which enables reduction of consumption of pressure oil supplied to the tensioner from a pressure oil source. <P>SOLUTION: The hydraulic tensioner includes a plunger movably housed in a reciprocating direction in a housing hole provided in a housing to apply tension to the chain, and the check valve unit. The check valve unit has the ball seat 141 provided with a valve oil path 143 communicated with an oil pressure chamber 131 formed between the housing and the plunger in the housing hole, and the check ball 147 which is seated to or separated from the ball seat 141 to thereby open and close the valve oil path 143. On the seat surface 142, a seat oil groove 150 is provided which causes the valve oil path 143 and the oil pressure chamber 131 to be connected when the check ball 147 is in a valve closed state. <P>COPYRIGHT: (C)2013,JPO&INPIT |
