Patent ID: 8522914
Filing Date: 2013-09-03
Classification: B62D,F02N,F04C

Abstract:
1. A pump apparatus for supplying a working fluid to a steering apparatus for a vehicle, the pump apparatus comprising: a pump housing having a pump element accommodating portion; a drive shaft rotatably supported by the pump housing; a cam ring movably disposed in the pump element accommodating portion; a pump element disposed within the cam ring, the pump element being rotationally driven by the drive shaft to suck the working fluid and discharge the working fluid sucked and vary a specific discharge quantity which is a discharge quantity of the working oil per one rotation of the pump element in accordance with variation in eccentric amount of the cam ring with respect to the drive shaft, and a solenoid which is drivingly controlled on a basis of a steering condition and a vehicle speed, the solenoid being operated to control the eccentric amount of the cam ring, wherein the solenoid is controlled to execute a flow rate reduction control during cranking of an engine of the vehicle in which the cam ring is allowed to move in such a direction as to reduce the specific discharge quantity, and wherein the solenoid is controlled to execute a flow rate increase control after the cranking is ended in which the cam ring is allowed to move in such a direction as to increase the specific discharge quantity.