US 12,281,663 B2
Fluid circuit
Yoshiyuki Shimada, Tokyo (JP); Koji Sato, Tokyo (JP); Yuta Okamoto, Tokyo (JP); Tomoki Seki, Tokyo (JP); and Tatsuhiro Arikawa, Tokyo (JP)
Assigned to EAGLE INDUSTRY CO., LTD., (JP)
Appl. No. 18/284,520
Filed by EAGLE INDUSTRY CO., LTD., Tokyo (JP)
PCT Filed Mar. 17, 2022, PCT No. PCT/JP2022/012346
§ 371(c)(1), (2) Date Sep. 27, 2023,
PCT Pub. No. WO2022/209969, PCT Pub. Date Oct. 6, 2022.
Claims priority of application No. 2021-059974 (JP), filed on Mar. 31, 2021.
Prior Publication US 2024/0159255 A1, May 16, 2024
Int. Cl. F15B 3/00 (2006.01); F04B 9/109 (2006.01); F15B 9/08 (2006.01)
CPC F15B 3/00 (2013.01) [F04B 9/109 (2013.01); F15B 9/08 (2013.01); F15B 2211/20538 (2013.01); F15B 2211/40515 (2013.01); F15B 2211/4159 (2013.01); F15B 2211/7716 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A fluid circuit, comprising:
a pump configured to deliver a working fluid; and
a pressure-increasing device configured to increase a pressure of the working fluid,
wherein the pressure-increasing device includes a cylinder and a piston provided inside the cylinder configured to be reciprocatable in an axial direction, and to deliver the working fluid that is increased in pressure, from the cylinder by pressing the piston inside the cylinder with the working fluid delivered from the pump,
the cylinder includes a first pressure-receiving chamber configured to apply the working fluid delivered from the pump, to the piston toward a first axial side, and a second pressure-receiving chamber configured to apply the working fluid delivered from the pump, to the piston toward a second axial side opposed to the first axial side,
a first switching valve configured to switch between a first flow passage which allows communication between the first pressure-receiving chamber and a side of the pump and a flow passage which allows communication between the second pressure-receiving chamber and on the side of the pump, according to a change in a fluid pressure to be applied, and a second switching valve configured to switch to a flow passage which applies the fluid pressure to the first switching valve,
the second switching valve includes a return device configured to reciprocate between an operation position to which the second switching valve is moved by a stroke of the piston and a return position to which the second switching valve is moved by the return device,
the piston and the second switching valve are movable independently of each other,
the cylinder is provided with a first pressure-increasing chamber configured to communicate with the first flow passage and a second pressure-increasing chamber configured to communicate with the second flow passage; and
the fluid circuit further comprises a first check valve disposed between the first flow passage and the first pressure-increasing chamber and configured to allow only the working fluid to flow from the first flow passage to the first pressure-increasing chamber, and a second check valve disposed between the second flow passage and the second pressure-increasing chamber and configured to allow only the working fluid to flow from the second flow passage to the second pressure-increasing chamber.