Caterpillar Sarl

Caterpilalr Sarl

Kouji Kishida

Nobuaki Matoba

Yoshihiko Hata

Yuya Kanenawa

Shigeo Kajita

Tetsuya Yoshino

Corey Lee Gorman

Takeshi Tsuneyoshi

Kazumasa Matsumura

Shuji Kidoguchi

Kentaro Nakayama

Shogo Tada

Shuhei Orimoto

Marilyn E Worley

Michihiro Izawa

Shinichi Nishiyama

Mitsuhiro Toyoda

Andy Fung

A machine is adapted for operation powered by any one of a plurality of interchangeable power sources. The machine may include an undercarriage configured for supporting ground engagement members that propel the machine and an upper structure rotatably supported on the undercarriage. The upper structure may include a swing frame, with the swing frame supporting an operator cab, any one of the plurality of interchangeable power sources, hydraulic components, electrical components, and a counterweight disposed at a first end of the swing frame. The counterweight may include a hollowed out portion facing toward the swing frame. The hollowed out portion of the counterweight may be centrally aligned with a center core portion of the swing frame configured for supporting any one of the plurality of interchangeable power sources, with the one power source being partially accommodated within the hollowed out portion of the counterweight.

Machine configuration and control system enabling interchangeable power sources

A hydraulic working machine is provided that uses a variable displacement pump and open center type flow rate control valve for a controlling a hydraulic actuator, and has a negative control throttle disposed in a center bypass oil passage to generate a negative control pressure. A hydraulic pump control system performs virtual bleed-off control for reducing the bleed-off flow rate of the center bypass oil passage, and can operate the hydraulic actuator with the same performance as an open center control. The control system includes a bypass cut valve disposed upstream from the negative control throttle to reduce flow through the center bypass oil passages, and a negative control pressure output valve that outputs a virtual negative control pressure. The control system is configured to reduce the bleed-off flow rate by operating the bypass cut valve when virtual bleed-off control is performed, and to reduce the pump flow rate by the bleed-off reduction flow rate.

Hydraulic pump control system of hydraulic working machine

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

A control device for suppressing engine load fluctuation according to main pump circuit conditions, wherein an assist torque calculation task includes a target engine torque calculation task separating smooth torque components from main pump load torque and setting a minimum value of either smooth torque component or engine setting torque as target engine torque, and a subtractor calculating target assist torque based on a difference between the main pump load torque and the target engine torque, the assist torque calculation task controlling a capacity of an assist pump based on the target assist torque and controlling switching between an assist mode and a charge mode.

Control device and working machine

An inexpensive engine assist device capable of performing stable energy regeneration from an accumulator and a working machine on which the engine assist device is mounted are provided. A variable capacity type main pump and a variable capacity type assist pump are directly connected to an engine. A return pressure oil flowing out from a fluid pressure actuator is temporarily accumulated by a sub-accumulator and is supplied to an inlet of the assist pump, and the assist pump pressurizes the return fluid pressure oil and supplies the return fluid pressure oil to a main accumulator. A controller calculates and controls an assist pump swash plate angle, and assist starting torque or charge starting torque, and introduces a pressure-accumulated fluid discharged from the main accumulator to the inlet of the assist pump or introduces a pressurized fluid discharged from an outlet of the assist pump into the main accumulator.

Engine-assist device and industrial machine

Growing community of inventors

Tokyo, Japan

Kouji Kishida