Abstract: An oil pump includes: a rotor 3 for actuating a pump action to suck oil in a suction passage 24 from a suction port 27 to supply oil to a delivery passage by way of a delivery port 19; and a flow control valve for returning an excessive oil from the delivery passage to the suction passage 24 as a returning flow of oil by way of a bypass passage 29 when a flow amount of oil is excessive in the delivery passage. A corrosion-proof member 9 having corrosion resistance is disposed at the position which faces to the returning flow of oil in the inner wall surface of at least one of the suction passage 24 and the bypass passage 29. The corrosion-proof member 9 has a discontinuous shape (for example a V-shape or a U-shape) in a circumferrencial direction of center line P1 in a cross section which intersects the center line P1 at right angles.

Abstract: An oil pump includes: a rotor 3 for actuating a pump action to suck oil in a suction passage 24 from a suction port 27 to supply oil to a delivery passage by way of a delivery port 19; and a flow control valve for returning an excessive oil from the delivery passage to the suction passage 24 as a returning flow of oil by way of a bypass passage 29 when a flow amount of oil is excessive in the delivery passage. A corrosion-proof member 9 having corrosion resistance is disposed at the position which faces to the returning flow of oil in the inner wall surface of at least one of the suction passage 24 and the bypass passage 29. The corrosion-proof member 9 has a discontinuous shape (for example a V-shape or a U-shape) in a circumferrencial direction of center line P1 in a cross section which intersects the center line P1 at right angles.