Patent ID: 7553134

Claim:
A switching valve structure of a fluid machine having a pump mode, to discharge a fluid under pressure, and a motor mode, to output mechanical energy by converting fluid pressure, at the time of expansion, into kinetic energy, wherein, in a case where the pump mode is executed, a communication path between a high-pressure chamber and a working chamber of the fluid machine is closed, and in a case where the motor mode is executed, the communication path is opened by a valve unit, wherein the valve unit includes a spool portion, which is adapted to slide in a direction substantially perpendicular to a surface to which the communication path is open on the valve unit side thereof, and a valve portion, which is arranged at the forward end of the spool portion, is located in the high-pressure chamber, and is adapted to slide with the spool portion for opening/closing the communication path, wherein a swivel mechanism, which is adapted to tilt the sliding axis of the valve portion with respect to the sliding axis of the spool portion at an arbitrary angle, is arranged between the spool portion and the valve portion, wherein in a case where the pump mode is executed, a discharge port conducts flow from the working chamber to the high-pressure chamber, and the discharge port is prevented from conducting flow from the high-pressure chamber to the working chamber by a check valve, which is adjacent to the valve unit in the high-pressure chamber, and wherein, in a case where the motor mode is executed, the valve unit opens the communication path, so that the communication path is open to flow from the high-pressure chamber to the working chamber.