PURPOSE: To convey an operating liquid of a pump anytime intermittently by providing two pump outlets and enabling one of the pump outlets to be communicated freely with the inside of a pump housing at a prescribed rotary angle through a rotary side valve.

CONSTITUTION: An eccentric 2 is formed integrally at a driven axis 1 and a piston 4 is slidden in a cylinder chamber 6 provided toward a radius direction corresponding to a pump housing 5 by a rotation of the eccentric 2 through a bearing 3. An operating liquid absorbed in the cylinder chamber 6 is pressurized and discharged to a passage 7 by the movement of the piston 4. In such a pump, the passage 7 branches off into the first and second outlets 8, 9, the first outlet 8 is opened to a peripheral face and the second outlet 9 is conducted to a liquid pressure passage to control a valve 14 for a combustion engine. When a recessed portion 11 is connected with the outlet 8 by a rotation of the rotary slide valve 10, an operating liquid is returned into a housing 5 through the passage 12.