Concept and Current Status of Floating Front Drive Axle

The suspended front axle referred to on the tractor is developed based on the concept of a car's front suspension, adding a suspension mechanism and an electronic control device to a rigid front axle. Its basic function is still to connect the front wheels, bear the weight distributed at the front end of the vehicle through the swing axle, and thus complete the tractor's straight-line or turning travel. Unlike a rigid front axle, the electronically controlled suspended front axle also receives sensor signals such as braking, speed, clutch, and the high and low positions of the front part of the vehicle through a control bus (e.g., CAN), and can adjust or buffer the impact received by the tractor in real time, improving the smoothness of the tractor's driving, improving the tractor's traction performance, and achieving comfortable driving. The electronically controlled suspended front drive axle can be powered by the tractor chassis, providing the power supply for the electronic control unit, the hydraulic power source for the suspension cylinder, and the CAN bus signal. Its suspension adjustment function is automatically completed by the suspension controller. Therefore, from the perspective of control theory, a more advanced electronically controlled suspended front drive axle is a closed-loop system, or a relatively independent electromechanical-hydraulic control system, which is an active suspension structure.
Currently, there are no manufacturers of electronically controlled suspended front drive axles in China. Internationally, only some large companies or manufacturers have applied it to tractors. Some of these companies have developed matching electronically controlled suspended front axles themselves, but the main trend is to cooperate with professional transmission system companies or jointly develop and match electronically controlled suspended front drive axles.