Caterpillar Sarl

Caterpilalr Sarl

Shuhei Orimoto

Koichi Kiyasu

Hideki Nakajima

Nobuaki Matoba

Yuya Kanenawa

Kouji Kishida

Yoshihiko Hata

Naoki Kuroda

Hiroshi Maeda

Mitsuhiro Toyoda

To provide a drift-prevention valve device, a blade device, and a working machine capable of operating an actuated unit and preventing the machine body from drifting with a simple configuration. The drift-prevention valve device is provided with a non-return valvethat allows the flow of hydraulic oil from a control valveto a head chamberof a blade cylinderand blocks the flow of the hydraulic oil in the reverse direction; and a piston accommodation partseparately disposed from an accommodation partof the non-return valve, configured to movably accommodate a power piston. The power pistondefines a first piston chambercommunicating with a rod chamber ofof the blade cylinderand a second piston chamberfor drain positioned on a poppetside of the non-return valveand communicating with a tank. The power pistonis connected to the poppetof the non-return valve, so that the power pistoncan be operated by the difference between the urging force of the poppetby a springof the non-return valveand a rod chamber pressure of the blade cylinder

Drift-prevention valve device, blade device, and working machine

It is to provide a control valve that can make the valve body smaller and the structure simplified and the hydraulic pressure system equipped therewith. The plural number of parallel feeder oil paths that are respectively connected to the plural number of pumps and are not cut off by displacement of spools is provided in the valve body in a linearly through all spool holes. For each section, a connection oil path is provided to connect any one side of parallel feeder oil paths to the bridge circuit B of the internal spools. Parallel feeder oil paths can be positioned in a simple shape, but also, just by properly providing connection oil paths, without depending on each section belonging to any of pump systems, positioning of section can be freely done within the valve body. Making the valve body smaller and the structure simplification can be executed.

Valve apparatus and fluid pressure system equipped therewith

To reduce the cost by reducing the number of parts and simplify the control of regeneration in the hydraulic actuator even though the meter-in control and the meter-out control can be performed separately while the supply and the discharge of hydraulic fluid is controlled. A meter-in valve that controls supply flow from a hydraulic pump into a hydraulic cylinder is provided, and meter-out switching valve that switches the direction of supply and discharge of the hydraulic oil into the hydraulic cylinder and controls the discharge flow from the hydraulic cylinder to the oil tank is installed on the down stream side of the meter-in valve, and further, a regeneration control valve is installed on the down stream side of the meter-out switching valve.

Hydraulic actuator control circuit

Provided are a hydraulic circuit and a work machine capable of improving an initial motion speed of a hydraulic cylinder during a contraction of the hydraulic cylinder and securing a necessary pump flow rate while hydraulic fluid is being accumulated in an accumulator. Hydraulic oil from a head side of a second boom cylinder is regenerated in a first boom cylinder and the second boom cylinder through a second control valve of a regeneration circuit. At the same time, oil from the head side of the first boom cylinder is accumulated to a first accumulator by a pressure accumulating circuit through a first control valve. The hydraulic oil supplied under pressure from a main pump is fed to a rod side of the first boom cylinder by a boom control valve. A bleed-off valve of a bleed-off circuit communicates the first control valve to a tank at the time of initial operation of the first control valve, thereby releasing hydraulic oil from the head end of the first boom cylinder to improve an initial motion speed.

Hydraulic circuit and working machine

Growing community of inventors

Tokyo, Japan

Shuhei Orimoto