Komatsu Corporation

Eiji Yamaguchi

Takashi Kuse

Kyousuke Moriguchi

Masaaki Kuma

Hironori Torisu

A transmission for a wheel loader includes a first oil accumulating part accumulating scattered lubricating oil and a second oil accumulating part accumulating the lubricating oil from the first oil accumulating part. The first oil accumulating part communicates with the second oil accumulating part through a communication oil path. Lubricating oil accumulated in the second oil accumulating part is directed to a lubricated part through a lubrication oil path when a rotary shaft is rotated at a rotational speed less than a predetermined rotational speed. The second oil accumulating part includes a shaft end space disposed at an end of the rotary shaft that accumulates the lubricating oil from the first oil accumulating part. A horizontal hole formed in a center part of the rotary shaft and extending axially allows the shaft end space and the vertical hole to communicate with each other.

Wheel loader

A transmission for a wheel loader includes first and second oil accumulating parts, a communication oil path, a horizontal hole and a vertical hole. The first oil accumulating part accumulates scattered lubricating oil. The second oil accumulating part is mounted to an end of an output shaft below the first oil accumulating part, and accumulates the lubricating oil from the first oil accumulating part. The communication oil path allows the first and second oil accumulating parts to communicate with each other. The horizontal hole extending axially is formed in the rotary shaft, and communicates with the second oil accumulating part. The vertical hole communicating with the horizontal hole is formed in the output shaft, and directs the lubricating oil accumulated in the second oil accumulating part to the lubricated part when the output shaft is rotated at a rotational speed lower than a predetermined rotational speed.

In a work vehicle, a control unit is configured to control a lock-up hydraulic pressure for controlling switching of a lock-up clutch. The control unit is configured to execute a lock-up slippage control for switching the lock-up clutch into a slippage state when the work vehicle starts moving. The control unit is configured to control the lock-up hydraulic pressure based on work instrument load information, pertaining to a load of a work instrument during execution of the lock-up slippage control.

Work vehicle and method of controlling the same

A lubricating oil supply control device controls a lubricating oil supply amount to a transmission in a construction machine including a torque converter with a lock-up clutch. The lubricating oil supply control device includes a clutch state determining section, a lubricating oil amount detecting section and a lock-up clutch controlling section. The clutch state determining section determines whether or not the lock-up clutch is being coupled. The lubricating oil amount detecting section detects whether or not the lubricating oil supply amount to the transmission is short of a preliminarily set supply amount. The lock-up clutch controlling section decouples the lock-up clutch when the lock-up clutch is being coupled and the lubricating oil supply amount is short of the preliminarily set supply amount.

Lubricating oil supply control device for construction machine

Provided is a device for performing speed change not leading to engine stall in a working vehicle such as a wheel loader while sustaining a required tractive force and reducing fuel consumption. When a speed ('forward', 'second speed') suitable for a work is selected by a speed change operator, control means makes a modulation clutch engaged in response to the vehicle speed drop and makes a lock-up state where a lock-up clutch is engaged transit to a lock-up and modulation clutch slip state where the lock-up clutch is engaged while the modulation clutch slips. Subsequently, the control means performs a clutch control for causing a transition to both clutch slip state where the lock-up clutch and the modulation clutch slip in response to the vehicle speed drop, hence causing the transition to a torque converter operation state where the modulation clutch is engaged and the lock-up clutch is released.

Growing community of inventors

Komatsu, Japan

Eiji Yamaguchi