The new aircraft tractor absorbs the latest scientific research results in vehicle driving mechanics and modular design methods, four-wheel drive. The tractor hydraulic drive system adopts a diesel engine speed control variable pump and a variable motor super-running automatic control system. After the pre-selected driving direction, when the diesel engine speed rises to a certain value, the variable pump displacement will gradually increase, and the variable motor displacement will gradually decrease, and the corresponding traction speed will increase accordingly.
Conversely, if the diesel engine speed decreases, the variable pump displacement gradually decreases to zero, and the motor displacement increases until the maximum basket. At this time, the corresponding travel speed is also reduced, and the hydraulic system and the engine can absorb the vehicle kinetic energy. Braking, this control system allows the driver to operate the engine oil pedal only by arching: starting, accelerating, decelerating, and braking of the tractor. The system's pressure feedback loop is used to limit operating pressure and prevent engine overload. And make the engine run under favorable conditions. The manual servo variable device can grasp the operation requirements, set the maximum speed limit of the tractor in real time, the well makes the reversing without impact, and also has the emergency braking capability.