| 摘要 |
PURPOSE:To accomplish an optimal control for the opening and closing of intake valve and exhaust valve, by providing a control arm for varying the valve lift according to the engine speed in a tappet for opening and closing an intake valve or exhaust valve. CONSTITUTION:Cap member 11 interconnected to an intake valve or exhaust valve (not shown) is fitted into tappet 10 which is held in contact with cam 2 on cam shaft 1. In tappet 10, there is provided a valve seat 14 for check valve 15. On the opposite sides of the valve seat 14, there are formed an oil chamber 24 inside the check valve seat 14 and a check-valve oil chamber 25. Further, on the outside of tappet 10, there are formed an oil supply chamber 20 communicated to oil supply passage 22 and an oil discharging chamber 21 communicated to oil discharging passage 23. Chambers 20 and 24 are communicated with each other via oil supply port 12, and a sliding member 18 is provided for opening and closing the port 12. With such an arrangement, the amount of oil to be supplied to chambers 24, 25 is controlled by moving the sliding member 18 vertically by means of a controlling arm 19 which is driven in response to the engine speed. |
