Hydraulic pressure supply system of automatic transmission

A hydraulic pressure supply system of an automatic transmission for a vehicle, comprising:

• a hydraulic pump provided with first and second pump chambers formed therein, wherein the first and second pump chambers are connected to an oil pan respectively through first and second input lines and discharge generated hydraulic pressure respectively through first and second discharge lines;
• a high-pressure regulator valve disposed on a high-pressure line connected to the first discharge line and a high pressure portion, and controlled by a first solenoid valve such that hydraulic pressure supplied from the first and second pump chambers to the high pressure portion through the high-pressure line is regulated to stable hydraulic pressure and surplus hydraulic pressure is supplied to a low pressure portion through a first recirculation line;
• a first switch valve controlled by a second solenoid valve and selectively connecting a first supply line connected to the high-pressure line through a bypass line or a second supply line to the second discharge line such that the hydraulic pressure generated at the second pump chamber is selectively supplied to the first supply line or the second supply line;
• a second switch valve controlled by the second solenoid valve, and supplying hydraulic pressure supplied through the first supply line to a third supply line or supplying hydraulic pressure supplied through the second supply line to a fourth supply line;
• a solenoid regulator valve regulating the hydraulic pressure supplied through the third supply line or the fourth supply line to stable hydraulic pressure, supplying the stable hydraulic pressure to a shift control portion through a fifth supply line, and supplying surplus hydraulic pressure to the low pressure portion;
• and
• a low-pressure regulator valve regulating the surplus hydraulic pressure supplied from the high-pressure regulator valve and the solenoid regulator valve to stable hydraulic pressure, supplying the stable hydraulic pressure to the low pressure portion, and recirculating surplus hydraulic pressure to the first input line through a second recirculation line.