| 摘要 |
<p>[Problem] To improve responsiveness of control for changing the pump volume in a variable volume oil pump (5) mounted in an engine (1), etc. [Solution] A variable volume mechanism of an oil pump (5) is provided with a volume adjustment member (for example, an adjustment ring (53)) which is displaced by the pneumatic pressure in a control oil pressure chamber (for example, a control space (TC)) provided inside of a housing (50), and a biasing means (for example, a coil spring (54)) which biases the volume adjustment member towards an orientation in which the volume of said control oil pressure chamber is smaller, and the variable volume mechanism is operated by the control oil pressure supplied to the control oil pressure chamber from an OCV (60), etc. A communication oil passage (53f) is provided such that, at least when the volume adjustment member is operated towards the orientation in which the volume of the control oil pressure chamber becomes smaller, the control oil pressure chamber communicates with a negative pressure source (for example, a suction port (50d)) such that oil is sucked out by the negative pressure.</p> |
