Patent ID: 7055320

Claim:
An actuator comprising: a pump mechanism which sucks/discharges a pressure fluid by displacing pump pistons in an axial direction in accordance with a rotary driving force of a pump-driving section to be driven and rotated by an electric signal; and a driving mechanism including a displaceable member which is displaceable in said axial direction by pressure of said pressure fluid to be supplied from said pump mechanism, wherein: said pump mechanism and said driving mechanism are provided in an integrated manner, and said pump mechanism includes an adjusting section which is provided in said pump mechanism and which adjusts an amount of discharge of said pressure fluid supplied to said driving mechanism; said adjusting section comprises a tilting member which is rotatably supported tiltably by a body of said pump mechanism and which is engaged with said pump piston, wherein an amount of displacement of said pump piston in said axial direction is adjusted by a tilting action of said tilting member; said driving mechanism includes first and second cylinder chambers in which said displaceable member is provided displaceably, and said first and second cylinder chambers communicate with an interior of said pump mechanism via first and second passages respectively; and said first and second passages are formed in an end plate of said pump mechanism and a cylinder tube and a cover member of said driving mechanism.