Kubota Corporation

Atsushi Hayashi

Akihiro Matsuzaki

Toshimitsu Yazaki

Kenichi Iwami

Shigeki Hayashi

Nobuyuki Okabe

Kazuma Ishihara

Shinnosuke Ishikawa

Minoru Hiraoka

Masakazu Hino

Yuji Imanaga

Masaru Andou

Yoshihiro Mitobe

A suspension system for a traveling vehicle body is disclosed. The system includes a suspension reference position varying mechanism () for varying a reference position of a suspension stroke of the suspension mechanism (), and a controller () configured to calculate an intermediate value from a maximal value corresponding to the maximal position of the suspension stroke and a minimal value corresponding to the minimal position of the suspension stroke, and to control the suspension reference position varying mechanism such that, when the calculated intermediate values deviates from a set target range, the intermediate value is displaced toward the target range. The controller () increases a control execution frequency for the suspension reference position varying mechanism () when the traveling speed of the vehicle body is low, and reduces the control execution frequency for the suspension reference position varying mechanism () when the traveling speed of the vehicle body is high.

Suspension system

A work vehicle includes an engine, a fuel tank that has a fuel supply inlet and stores engine fuel, and a liquid tank that has a liquid supply inlet and stores purification liquid that is used in purification of engine exhaust gas. The liquid tank is protected by the fuel tank so that the liquid tank is not directly exposed to hot air from the engine.

Fuel tank and liquid tank configuration for a work vehicle

The hydraulic suspension system comprises a suspension mechanism for a traveling vehicle body, a suspension reference position variation mechanism for varying a reference position of a suspension stroke of the suspension mechanism, and a stopped state detector for detecting a state in which operation of the suspension mechanism has stopped. The control management unit controls the suspension reference position variation mechanism so that when operation of the suspension mechanism is detected by the stopped state detector to be in a stopped state, the operation of the suspension mechanism moves toward a target range, in preference to control based on a suspension stroke position obtained from a suspension stroke position sensor.

Hydraulic suspension system for work vehicle

The hydraulic suspension system comprises a suspension mechanism () for a traveling vehicle body, a suspension reference position variation mechanism () for varying a reference position of a suspension stroke of the suspension mechanism, and a stopped state detector () for detecting a state in which operation of the suspension mechanism () has stopped. The control management unit () controls the suspension reference position variation mechanism () so that when operation of the suspension mechanism () is detected by the stopped state detector () to be in a stopped state, the operation of the suspension mechanism () moves toward a target range, in preference to control based on a suspension stroke position obtained from a suspension stroke position sensor ().

A tractor is provided for suppressing pitching in which a front part of a traveling vehicle body is lifted upward, while a suspension mechanism functions when work is carried out with a ground implement. When a raise control signal for raising the plow is detected in draft control for elevating/lowering the plow based on a draw load value detected by a draw load sensor, mode switching means suppresses or limits the suspension function, via control of the suspension control means to suppress an event in which the front part of the traveling vehicle body is lifted upward. When the raise control signal is not detected, the mode switching means causes the suspension mechanism to function via control of the suspension control means.

Tractor

A transmission apparatus for a tractor is operable to transmit a forward drive force in a wide speed changing range to the traveling device and which is operable also to transmit a reverse drive force to the traveling device. A planetary transmission section is configured to output the forward drive force in whichever case a hydrostatic stepless speed changing section is speed-changed to a forward rotation speed change state or a reverse rotation speed change state. A low speed transmission clutch couples a low speed side speed changing gear to a counter shaft to be rotatable therewith. A high speed transmission clutch couples a high speed side speed changing gear to the counter shaft to be rotatable therewith. A reverse transmission clutch couples a reverse transmission gear to an output shaft to be rotatable therewith.

Transmission apparatus for a tractor

A suspension system for a vehicle includes a swing frame and right and left suspension cylinders for front wheels. The swing frame is swingably supported by the front portion of a vehicle body about a support shaft extending in a lateral direction, and supports the front axle case, so as to allow the front axle case to swing about a center shaft extending in a front-rear direction. The right and left suspension cylinders are provided on the swing frame. A lateral oscillation regulation unit is provided between the swing frame and the front frame, and configured to regulate an oscillation of the swing frame by contact in the lateral direction.

Suspension system for vehicle

A hydraulic suspension system includes a suspension base () supporting wheels, a hydraulic cylinder () for displaceably suspending the suspension base from a vehicle body, and an oil passage connected to the hydraulic cylinder. An accumulator () is incorporated within the oil passage. A flow control valve () is incorporated at an oil passage portion between the hydraulic cylinder and said accumulator for controlling an amount of work oil flowing therebetween. A pressure sensor () is provided for detecting a cylinder oil passage pressure effective on the hydraulic cylinder. A control unit () is provided for controlling operation of the flow control valve, based upon a detection value from the pressure sensor.

Growing community of inventors

Nara, Japan

Atsushi Hayashi