VEHICULAR INTERNAL GEAR TYPE OIL PUMP

摘要

An oil pump includes a first spill passage formed on a side surface (60) of a pump chamber (58) to communicate a hydraulic pressure chamber (54) with a first high pressure discharge passage (68) when the entire hydraulic pressure chamber (54) is positioned between the first high pressure discharge passage (68) and a first low pressure discharge passage (70). Therefore, when the hydraulic pressure chamber (54) passes between the first high pressure discharge passage (68) and the first low pressure discharge passage (70), the hydraulic pressure inside the predetermined hydraulic pressure chamber (54) escapes to the first high pressure discharge passage (68) through a first spill passage (76), so a hydraulic pressure value inside the hydraulic pressure chamber (54) is maintained at the pressure value inside the first high pressure discharge passage (68). As a result, fluid is inhibited from flowing into the hydraulic pressure chamber (54) from the first high pressure discharge passage (68) through a space between inner peripheral teeth (48) and outer peripheral teeth (42).