Kyb Corporation

Kyb-ys Co., Ltd.

Takeuchi Mfg. Co., Ltd.

Keiichi Matsuzaki

Hideki Miyashita

Nobuyuki Kobayashi

Takeshi Terao

Shunsuke Fukuda

Hiroki Kondo

A fluid pressure control device includes a first switching valve provided on a downstream of a first travel control valve in the first main passage and having an open position and a priority position, a second switching valve provided on a downstream of a second travel control valve in the second main passage and having an open position and a priority position, and a merging passage connecting a downstream of the first switching valve and a downstream of the second switching valve. In a state where first work control valves and second work control valves are not operated and the first travel control valve is operated, the first switching valve is at a priority position, and in a state where the first work control valves and the second work control valves are not operated and the second travel control valves is operated, the second switching valve is at a priority position.

Fluid pressure control device

A fluid pressure control device includes a switching valve that has a pilot chamber to which the working oil is supplied from the supply passage through the second control valve, and a first relief valve that is provided on the downstream side of the switching valve. The second control valve allows supply of the working oil to the pilot chamber in a case where a flow of the working oil to a tilt cylinder is allowed, and blocks the supply of the working oil to the pilot chamber in a case where the flow of the working oil to the tilt cylinder is blocked. The switching valve allows a flow of the working oil to the first relief valve in a case where the working oil is supplied to the pilot chamber, and blocks the flow of the working oil to the first relief valve in a case where the supply of the working oil to the pilot chamber is blocked.

A rotary valve that controls a flow rate at which working oil is supplied to and discharged from a hydraulic cylinder that causes a wing to rotate about a rotary shaft includes a rotor that rotates as the wing rotates about the rotary shaft, and a first control flow passage and a second control flow passage formed in the rotor to control the flow rate at which the working fluid is supplied to and discharged from the hydraulic cylinder, wherein the first control flow passage and the second control flow passage respectively vary a resistance exerted on a flow of the working fluid passing therethrough as the rotor rotates.

Rotary valve and fluid pressure actuator unit including rotary valve

A fluid pressure control apparatus includes a pilot control valve configured to control a pilot pressure guided from a pilot pump to the control valve and a load retaining mechanism installed in the main passage. The load retaining mechanism includes an operated check valve configured to permit a flow of the working fluid from the load-side pressure chamber to the control valve in accordance with a back pressure and a switch valve configured to switch an action of the operated check valve. The switch valve has a discharge position configured to discharge the working fluid in a back pressure chamber when the pilot pressure has been guided from the pilot control valve. When the switch valve is set to the discharge position, the working fluid in the back pressure chamber is discharged to a tank via a drain port of the pilot control valve.

Growing community of inventors

Nagano, Japan

Keiichi Matsuzaki