Patent ID: 9291078
Filing Date: 2016-03-22
CPC Classification: F01M,F04B,Y10T

Claim Text:
1. A hydraulic pressure supply system of an automatic transmission for a vehicle which generates low hydraulic pressure and high hydraulic pressure using oil stored in an oil pan and supplies the low hydraulic pressure and the high hydraulic pressure respectively to a low pressure portion and a high pressure portion, the hydraulic pressure supply system comprising: a low-pressure hydraulic pump receiving the oil stored in the oil pan through a first input line, generating the low hydraulic pressure, and discharging the low hydraulic pressure to a first low-pressure line fluid-connected to the low-pressure hydraulic pump; a switch valve fluid-connected to the first low-pressure line, and selectively supplying the low hydraulic pressure supplied from the first low-pressure line to the low pressure portion or the high pressure portion, wherein the low pressure portion and the high pressure portion are connected to the switch valve; a low-pressure regulator valve fluid-connected to the switch valve through a second low-pressure line and controlling the low hydraulic pressure supplied from the switch valve through the second low-pressure line to be stable low hydraulic pressure, and supplying the stable hydraulic pressure to the low pressure portion through a third low-pressure line fluid-connecting the low-pressure regulator valve and the low pressure portion; a high-pressure hydraulic pump fluid-connected to the low-pressure hydraulic pump through the first low-pressure line and increasing the low hydraulic pressure supplied from the low-pressure hydraulic pump through the first low-pressure line to be the high hydraulic pressure, and discharging the high hydraulic pressure to a high-pressure line fluid-connected to the high pressure portion; a high-pressure regulator valve fluid-connected to the high pressure line and controlling the high hydraulic pressure supplied from the high-pressure hydraulic pump through the high-pressure line and the low hydraulic pressure supplied from the low-pressure hydraulic pump through the switch valve to be stable hydraulic pressure, and supplying the stable hydraulic pressure to the high pressure portion; and a second input line connecting the oil pan to the first low-pressure line, wherein the low-pressure regulator valve is controlled by elastic force of an elastic member disposed at a first side thereof and the low hydraulic pressure of the second low-pressure line supplied to a second side thereof, wherein the high-pressure regulator valve is selectively connected to the first low-pressure line through the switch valve and is directly fluid-connected to the high-pressure line, and wherein the high-pressure regulator valve supplies through a supply line a portion of the low hydraulic pressure supplied from the first low-pressure line or a portion of the high hydraulic pressure from the high-pressure line, to the low pressure portion.