| 摘要 |
PURPOSE:To always improve the good returning of oil in no relation to a mounting condition of an engine, by utilizing pulsating pressure generated in a crank chamber to circulate air and forcibly returning the oil in a rocker chamber through this circulative air flow to the crank chamber. CONSTITUTION:At operation of an engine, since pulsating pressure due to back pressure of a piston 6 is generated, air in a crank chamber 3 is discharged to a rocker chamber 13 via a discharge passage 24 while opening one check valve 21 by positive pressure of said pulsating pressure. Then the other check valve 23 is opened by negative pressure of the pulsating pressure to suck the air from the chamber 13 to the chamber 3 via a suction passage 27. In this way, oil in the chamber 13 is forcibly returned interruptively to the chamber 3 via the passage 27 synchronously with negative pulsating pressure in the chamber 3 further dropped and accumulated in an oil pan 7. A circulative air flow between said crank chamber 3 and the chamber 13 forcibly returns the oil to enable to improve the returning of the oil. |
