Komatsu Corporation

Satoshi Ishikawa

Shinobu Nagura

Masayuki Tajima

Masayuki Hosaka

Junichi Fukushima

Tomonobu Shioyasu

Masateru Hachisuka

Hirokazu Endoh

Keita Murakami

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 spool valve includes: a valve body that has a spool hole; and a spool disposed in the spool hole and movable in an axial direction, wherein the spool has a first large-diameter portion, and a small-diameter portion provided on one side in the axial direction of the first large-diameter portion, the first large-diameter portion has a first outer surface slidable with an inner surface of the spool hole, an end surface connected to an end portion at the one side in the axial direction of the first outer surface and to an end portion at the other side in the axial direction of an outer surface of the small-diameter portion, and a cutout portion provided on the end surface, and a bottom surface of the cutout portion is inclined toward the one side in the axial direction to approach a central axis of the spool.

Spool valve, operation device, and work vehicle

Growing community of inventors

Oyama, Japan

Satoshi Ishikawa