HYDRAULIC PRESSURE SUPPLY SYSTEM OF AUTOMATIC TRANSMISSION FOR VEHICLE

摘要

PROBLEM TO BE SOLVED: To provide a hydraulic pressure supply system of an automatic transmission for a vehicle capable of normal operation using a low pressure hydraulic pump when a high pressure hydraulic pump is out of order or is stopped.SOLUTION: A hydraulic pressure supply system of an automatic transmission for a vehicle, comprises: a low pressure hydraulic pump 2 receiving oil through a first input line 14 to discharge the oil to a first low pressure line 16; a first switch valve 10 opening or closing a hydraulic line from the first low pressure line; a low pressure regulator valve 12 regulating a hydraulic pressure supplied to the first switch valve through a second low pressure line 18 to supply the regulated hydraulic pressure to a low pressure portion 4 through a third low pressure line 24; a high pressure hydraulic pump 6 raising the hydraulic pressure supplied from the first low pressure line; a second switch valve 26 connecting or disconnecting between the first low pressure line and a high pressure line 28; a high pressure regulator valve 30 regulating the hydraulic pressure supplied from the high pressure line and the hydraulic pressure supplied from the low pressure hydraulic pump through the second switch valve to supply the regulated hydraulic pressure to a high pressure portion; and a second input line 38 connecting an oil pan with the first low pressure line.