Design and Comparative Study of the Hydrostatic Travelling System for Motor Graders

The motor grader is a high-speed travelling-type earth-moving machine widely used in infrastructure construction, of which the working device is driven by the travelling system to overcome the working load. At present, the power shift gear transmission is the major driving mode of high-power motor graders, yet the application of hydrostatic driving in travelling system is also of great research value and worth continuous exploration due to its unique advantages. In this paper, design of the open-loop and the closed-loop hydrostatic travelling systems of the motor grader is studied and compared by theoretical analysis, simulation and test. Firstly, the structure and the working principle of the two systems are introduced, and the acceleration performance, braking performance and the efficiency are calculated and compared quantitatively. Secondly, the simulation models of these two systems are built in AMESim software, and the simulation are carried out under two typical working conditions, i.e. starting and stopping processes. Next, the difference and the causes are discussed based on the test analysis of the performance of acceleration time, stopping distance, anti-drag phenomenon, peak pressure and suction of both the two systems. Finally, from the perspective of functionality, performance and manufacture cost, the advantages and the disadvantages of the two systems are summarized.