Hitachi Construction Machinery Co., Ltd.

Tcm Corporation

Koji Takano

Koji Hyodo

Nobuhiro Suzuki

Kazuo Chonan

Genichiro Ishimaru

Tetsuji Tanaka

Masaki Yoshikawa

Yasuo Yamazaki

Kazuo Ishida

Eiichi Sakai

Nobuyuki Hidaka

Seishi Morishita

Kenji Uezono

Akira Takeshita

Kiyoyasu Hasegawa

There are provided: a first circuit for traveling HC, formed through a closed circuit connection of a variable displacement hydraulic pumpand a variable displacement hydraulic motor, that includes a motor control unitthat controls a displacement of the hydraulic motor; a second circuit for working HCthat drives a work hydraulic actuatorby pressure oil from a work hydraulic pump; and a maximum value control unit that controls a maximum displacement of the hydraulic motorin accordance with load pressure Pf in the second circuit HC. The maximum value control unit decreases the maximum displacement to a minimum limit qcorresponding to a maximum load pressure Pr in the second circuit when load pressure Pf in the second circuit exceeds a predetermined value Ps.

Travel control apparatus for working vehicle

A speed change control system for an industrial vehicle includes: a speed ratio detecting unit that detects a speed ratio of speeds of an input shaft and of an output shaft of a torque converter; a torque converter speed ratio-based speed changer that shifts up or shifts down a speed stage of a transmissionin response to the detected speed ratio; a vehicle speed detection unit that detects a speed of the vehicle; a mode selection unit that selects any one of an L-mode and an H-mode; and a speed change control unit that permits an upshift provided that the vehicle speed is equal to or higher than a first predetermined value when the L-mode is selected whereas permits the upshift provided that the vehicle speed is higher than another predetermined value which is larger that the predetermined value when the H-mode is selected.

Speed change control system for industrial vehicle

A first motorand a second motorof variable displacement type are in parallel to each other connected to a hydraulic pumpin a closed circuit, through which the output torque from the first motoris transmitted to an output shaft. A clutch control unitcontrols a clutch deviceas: when the engine speed is N, which is the case where the accelerator pedal is fully depressed, the clutch is disengaged at the vehicle speed v. When the engine speed is N(&#x3c;N), which is the case where the accelerator pedal is half depressed, the clutch is disengaged at the vehicle speed v(&#x3c;v).

Clutch control device for hydraulically driven vehicle

A hydraulic power transmission device in a work vehicle transmits motive power from two hydraulic motors disposed in parallel to each other. The hydraulic power transmission device includes: a case; a first motor shaft and a second motor shaft respectively disposed in a right-side area and in a left-side area inside the case, each linked to one of the two hydraulic motors; a counter shaft disposed in an area ranging between the first motor shaft and the second motor shaft in the case; an output shaft; a first transmission mechanism that transmits motive power from the first motor shaft to the output shaft via the counter shaft; a second transmission mechanism that transmits motive power from the second motor shaft to the output shaft; and a hydraulic clutch device disposed at the counter shaft, that transmits the motive power from the first motor shaft to the output shaft or cuts off transmission of the motive power.

Hydraulic power transmission device and work vehicle

Growing community of inventors

Tsukuba, Japan

Koji Takano