Kyb Corporation

Kubota Corporation

Akio Matsuura

Shota Mizukami

Takeshi Terao

Yoshimitsu Tanaka

Teruo Kunizawa

Yuji Kawano

Shoichi Kawano

Tsukasa Haraguchi

Toshiaki Otani

Kunihiko Bito

Masaru Kumatani

Hitoshi Iwamura

Junki Maeda

Takehiro Wakasugi

In a valve device, travel control valve unit has a communication path causing the lead-out passages of the left and right travel control valve units to communicate with each other, and a spool has a lead-out side land portion configured to cause communication or shut-off of the communication between the lead-out passage and the communication path, a discharge-side land portion configured to cause communication or shut-off of the communication between the actuator passage and the discharge passage, a discharge portion configured to discharge a part of the working fluid led from the supply passage to the lead-out passage to the discharge passage at a movement initial stage of the spool, and a communication portion configured to cause the lead-out passage and the communication path to communicate with each other at a movement final stage of the spool.

Valve device

A control valve device includes a valve main body formed to have an actuator port connected to an actuator, a communication passage formed in the valve main body and configured to allow the actuator port to communicate with a drain port, and an on/off valve provided between the communication passage and the drain port, and the on/off valve includes a seat member assembled to the valve main body, an orifice provided in the seat member, and a poppet member configured to open and close a seat portion of the seat member.

Control valve device

A compensator spool of a load sensing valve device includes a pressure chamber, a compensator throttle portion, a pressure introduction chamber, a pressure introduction port, a maximum load pressure introduction chamber, and a selector valve. A groove is formed around the pressure introduction port, and a groove moves relatively between a passage communicating with an actuator to reduce an opening area of the pressure introduction port when the compensator spool moves.

Load sensing valve device

A hydraulic system for a work machine includes a first switch valve and a first return circuit. The first switch valve is switchable between a confluent position and an isolation position. The first switch valve is switched to the confluent position such that a first operation fluid tube is connected to a second operation fluid tube and a first transmission fluid tube is connected to a second transmission fluid tube. The first switch valve is switched to the isolation position such that the first operation fluid tube is disconnected from the second operation fluid tube and the first operation fluid tube is disconnected from the second operation fluid tube.

Hydraulic system for work machine

A valve device includes a valve body, a drain chamber wall configured to define a drain chamber, a drain port formed in the drain chamber wall facing the valving element, and a drain passage configured to guide drain fluid from another valve device to the drain chamber, wherein at least one of the drain chamber wall and the valving element includes a communicating passage configured to allow the drain port to communicate with the drain chamber when the movement of the valving element is restricted by the drain chamber wall.

Valve device and fluid pressure control device

A compensator spool of a load sensing valve device has a pressure chamber, a compensator throttle portion, a pressure introduction chamber, a pressure introduction port, a maximum load pressure introduction chamber, and a selector valve. A groove is formed around the pressure introduction port, and a groove moves relatively to a passage communicating with an actuator so as to reduce an area of an opening of the pressure introduction port when the compensator spool moves.

Growing community of inventors

Kanagawa, Japan

Akio Matsuura