Patent ID: 6135919
Filing Date: 2000-10-24
Classification: F16H,Y10T

Abstract:
An oil pump rotation speed control device for an automatic transmission of a vehicle, said transmission controlling the operation of a speed ratio control mechanism using oil pressure supplied from an oil pump, wherein said control device comprises:a first oil pump which supplies a required flow amount for speed ratio control of said speed ratio control mechanism;a second oil pump which supplies a flow amount for recycling to an oil cooler which cools said oil;a motor used for simultaneously driving said first and second pumps; anda controller which controls a rotation speed of said motor, said controller programmed tocalculate a required pump discharge amount of said first pump depending on driving conditions;calculate a required pump discharge amount of said second pump depending on driving conditions; andcontrol a rotation speed of said motor so that a pump rotation speed meets the greater of said required pump discharge amounts.