Komatsu Corporation

Junichi Fukushima

Shuuji Hori

Masato Kageyama

Hiroyuki Chikugo

Akira Hasebe

Mutsumi Ono

Satoshi Ishikawa

Keita Murakami

Masateru Hachisuka

Shunsuke Koike

In a pressure compensation valve, a spool portion of a valve body is provided with a throttle passage that constantly communicates with a pump port. A case is provided with supply pressure communication passages to block space between the throttle passage and a load pressure chamber when a poppet portion closes space between the pump port and a cylinder port by biasing force of a load pressure spring, and that, meanwhile, communicate between the throttle passage and the load pressure chamber via a throttle hole when the spool portion moves in an opening direction by a predetermined stroke. A lead-out pressure chamber that presses the poppet portion in a closing direction in a case where an internal pressure increases is provided between the poppet portion and the case, and a lead-out pressure passage that constantly communicates with the cylinder port is connected to the lead-out pressure chamber.

Pressure compensation valve

A hydraulic cylinder spool valve device, which extends and retracts a cylinder rod of a hydraulic cylinder, includes: a first spool valve having a first dead band and a first opening characteristic; a second spool valve having a second dead band and a second opening characteristic; and a controller performing communication with the hydraulic cylinder by using the first spool valve and positioning the second spool of the second spool valve within the second dead band and performing communication with the hydraulic cylinder by using the second spool valve and positioning the first spool of the first spool valve within the first dead band, and adjusting a characteristic of a switching dead band between the first opening characteristic and the second opening characteristic.

Hydraulic cylinder spool valve device

Growing community of inventors

Oyama, Japan

Junichi Fukushima