| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a variable displacement pump and the like capable of enhancing controllability of a discharge flow rate of a pump. <P>SOLUTION: The variable displacement pump, in which a pressure difference between the front and back of a metering orifice 60 is introduced that is constituted by a second orifice as a stationary orifice provided on a discharge passage, and a third orifice 63 as a variable orifice, includes a control valve for controlling the eccentricity of a cam ring according to the pressure difference, and a solenoid valve 50 for controlling a flowing sectional area of the third orifice 63 based on change of an electric current amount controlled depending on operating conditions of a vehicle, wherein sensitive change in the discharge flow rate in a state where the discharge flow rate of the pump is small, especially during high-speed running or the like can be suppressed, and controllability of discharge flow rate of the pump can be improved, by setting a ratio of change in specific discharge amounts (discharge amount per one revolution of pump) to change in the electric current amount to be supplied to the solenoid valve 50, such that the ratio becomes smaller in a state where a specific discharge amount is small than that in a state where the specific discharge amount is large. <P>COPYRIGHT: (C)2010,JPO&INPIT |
