VANE PUMP

A lubricating oil to be supplied to a vane pump 1 is supplied to a pump chamber 2A through an axial direction oil supply hole 11a, a diameter direction oil supply hole 11b, and an axial direction oil supply groove 11c of an oil supply passage 11. A gas passage 13 is comprised of a gas groove 13a whose one end is made to communicate with an outer space, the gas groove 13a being formed on an outer peripheral surface of a shaft part 3B of a rotor 3, and the other end of this gas groove is made to intermittently overlappingly communicate with the axial direction oil supply groove 11c by a rotation of the rotor. Clogging does not easily occur as compared with a case where the gas passage 13 is comprised of a through-hole as a conventional apparatus since the gas passage is comprised of the groove-shaped gas groove 13a, thus enabling to reduce a passage area of the gas passage. Hence, the air is prevented from being sucked in the pump chamber from the gas passage as much as possible, thereby enabling to prevent the increase of engine driving torque.