Abstract: A motor grader includes an engine, a torque converter, a drive wheel, an engine revolution detector, and a control unit. The torque converter, including a lock-up clutch, transmits driving force from the engine. The drive wheel is rotationally driven by the driving force from the engine. The engine revolution detector detects engine revolution. When the lock-up clutch is engaged, the control unit is configured to: maintain the engaged state of the lock-up clutch when the engine revolution is greater than a predetermined lock-up release revolution lower than a low idle revolution; and switch the lock-up clutch into a disengaged state when the engine revolution is less than or equal to the predetermined lock-up release revolution.

Abstract: A motor grader includes an engine, a torque converter, a drive wheel, an engine revolution detector, and a control unit. The torque converter, including a lock-up clutch, transmits driving force from the engine. The drive wheel is rotationally driven by the driving force from the engine. The engine revolution detector detects engine revolution. When the lock-up clutch is engaged, the control unit is configured to: maintain the engaged state of the lock-up clutch when the engine revolution is greater than a predetermined lock-up release revolution lower than a low idle revolution; and switch the lock-up clutch into a disengaged state when the engine revolution is less than or equal to the predetermined lock-up release revolution.

Abstract: Turning radius is calculated from steering angles of steering-wheels and articulation angles of respective frames, and the steering-wheels are automatically rotated faster than rear-wheels based on the turning radius, the revolution number of the rear-wheels, engine speed of an engine and a speed range of hydraulic motors, so that conventional trouble for manipulating operation lever etc. while turning a motor grader and skill-requiring work for adjusting the revolution number of the steering-wheels in accordance with the revolution number of the rear-wheels can be eliminated, thereby easily and accurately controlling the revolution number of the steering-wheels and securely preventing tight-corner braking phenomenon.

Abstract: In a working vehicle, an electronic control regulating valve 121 controls a connection force in clutch mechanisms 35 and 36 in a transmission 30, and a input side revolution signal of the transmission, an output side revolution signal, a speed stage position signal and a pedal angle signal of an inching pedal 114 are inputted to control a slip in the transmission 30. Further, a pedal angle signal of an accelerator pedal 107 is inputted to cope with a hyper-slow mode. Furthermore, in an engine, a charged pressure is controlled in stages to carry out an appropriate power control suitable for a number of stages of the transmission 30.

Abstract: In a working vehicle, an electronic control regulating valve 121 controls a connection force in clutch mechanisms 35 and 36 in a transmission 30, and a input side revolution signal of the transmission, an output side revolution signal, a speed stage position signal and a pedal angle signal of an inching pedal 114 are inputted to control a slip in the transmission 30. Further, a pedal angle signal of an accelerator pedal 107 is inputted to cope with a hyper-slow mode. Furthermore, in an engine, a charged pressure is controlled in stages to carry out an appropriate power control suitable for a number of stages of the transmission 30.

Abstract: In a working vehicle, an electronic control regulating valve 121 controls a connection force in clutch mechanisms 35 and 36 in a transmission 30, and a input side revolution signal of the transmission, an output side revolution signal, a speed stage position signal and a pedal angle signal of an inching pedal 114 are inputted to control a slip in the transmission 30. Further, a pedal angle signal of an accelerator pedal 107 is inputted to cope with a hyper-slow mode. Furthermore, in an engine, a charged pressure is controlled in stages to carry out an appropriate power control suitable for a number of stages of the transmission 30.

Abstract: In a working vehicle, an electronic control regulating valve 121 controls a connection force in clutch mechanisms 35 and 36 in a transmission 30, and a input side revolution signal of the transmission, an output side revolution signal, a speed stage position signal and a pedal angle signal of an inching pedal 114 are inputted to control a slip in the transmission 30. Further, a pedal angle signal of an accelerator pedal 107 is inputted to cope with a hyper-slow mode. Furthermore, in an engine, a charged pressure is controlled in stages to carry out an appropriate power control suitable for a number of stages of the transmission 30.

Abstract: Turning radius is calculated from steering angles of steering-wheels (2, 3) and articulation angles of respective frames, and the steering-wheels (2, 3) are automatically rotated faster than rear-wheels (4, 5) based on the turning radius, the revolution number of the rear-wheels (4, 5), engine speed of an engine (6) and a speed range of hydraulic motors (14, 15), so that conventional trouble for manipulating operation lever etc. while turning a motor grader (1) and skill-requiring work for adjusting the revolution number of the steering-wheels (2, 3) in accordance with the revolution number of the rear-wheels (4, 5) can be eliminated, thereby easily and accurately controlling the revolution number of the steering-wheels (2, 3) and securely preventing tight-corner braking phenomenon.

Abstract: In a working vehicle, an electronic control regulating valve 121 controls a connection force in clutch mechanisms 35 and 36 in a transmission 30, and a input side revolution signal of the transmission, an output side revolution signal, a speed stage position signal and a pedal angle signal of an inching pedal 114 are inputted to control a slip in the transmission 30. Further, a pedal angle signal of an accelerator pedal 107 is inputted to cope with a hyper-slow mode. Furthermore, in an engine, a charged pressure is controlled in stages to carry out an appropriate power control suitable for a number of stages of the transmission 30.

Abstract: A work machine lever for a work vehicle comprises a base end portion supported in a steering-wheel-support box and a free end portion disposed on a side of a steering wheel. The free end portion is provided with a lever-operating portion, which can be pivotally rotated between at least two positions, i.e., an operating position on the side of the steering wheel and a non-operating position in front of the steering wheel about a support base end portion of the steering-wheel-support box as a pivot and can be fixed at the respective rotation positions. Therefore, when the operator gets on and off the vehicle, the work machine lever is rotated to be fixed at a forward lever non-operating position to form a large passage space on a side of the steering wheel.