자동변속기용 단독 구동 동축 2단 전동식 오일펌프 특성 분석

Automatic oil pump pressurizes oil for transmission components to operate under high pressure and circulates oil to the lubricating part under low pressure. The oil pump elevates oil pressure to high level to be possible to transfer torque. Pressure control valves in the valve body reduces the pressure of some of the pressurized oil to low level. That is, over-design of the oil pump is a major cause of power loss and it is possible to reduce power loss by separating oil pump into the high pressure pump and low pressure pump. This paper introduces the 2-stage oil pump which has two oil pump in one housing and is driven by the same shaft, the low pressure pump supplies lubricating oil and the high pressure pump generates transmission oil pressure. In this paper the performance of th 2-stage oil pump for automatic transmission system is analyzed by computational fluid dynamic method.