Abstract: A travel vibration suppressing device is connected to a hydraulic cylinder for operating a work machine, and utilizes an accumulator to suppress vibration during travel of the vehicle. Upon determining that the state of the work machine is the excavating state, the control unit switches from a state of communication between a hydraulic cylinder and the accumulator to a blocked state when the vehicle speed changes from a speed exceeding a first speed to a speed equal to or less than the first speed. Upon determining that the operating state is the normal state, the state of communication between a boom cylinder and the accumulator is switched to the blocked state when the vehicle speed changes from a second speed lower than the first speed to a speed equal to or less than the second speed.

Abstract: A travel vibration suppressing device is connected to a hydraulic cylinder for operating a work machine, and utilizes an accumulator to suppress vibration during travel of the vehicle. Upon determining that the state of the work machine is the excavating state, the control unit switches from a state of communication between a hydraulic cylinder and the accumulator to a blocked state when the vehicle speed changes from a speed exceeding a first speed to a speed equal to or less than the first speed. Upon determining that the operating state is the normal state, the state of communication between a boom cylinder and the accumulator is switched to the blocked state when the vehicle speed changes from a second speed lower than the first speed to a speed equal to or less than the second speed.

Abstract: A loading operation vehicle can reduce a specific fuel consumption during a traveling time and can improve operability of a driving characteristic. The vehicle is provided with output characteristic changing means (38, 48) for changing an output characteristic of an engine (1) in a plurality of stages, shift timing changing means (39) for changing a shift timing of an automatic transmission (9) in a plurality of stages, working machine flow amount changing means (32, 50) for changing a working machine flow amount of a pressurized oil flowing through a working machine actuator (42) in a plurality of stages, mode setting means (40) for combining the output characteristic of the engine, the shift timing of the automatic transmission and the set value of the working machine flow amount with each other so as to set a plurality of modes, and mode selecting means (45) for freely selecting from the modes.

Abstract: A hydraulic control device for a working vehicle capable of enhancing excavating ability even when earth to be excavated is hard is provided.