STUDY OF LOADER TRANSMISSION DYNAMICS WITH HIGH TORQUE STEP-ADJUSTABLE HYDROMOTOR-WHEELS

Goal. The purpose of the article is to analyze the dynamics of the hydraulic fluid power of the forklift transmission equipped with radial-piston high- torque multi-cycle hydraulic motors with a step change in working volume. Such a transmission is offered as a gearless one compared to the use of traditional transmissions with axial-piston hydraulic motors and gearboxes in front of the drive wheel hub. Research methodology. The traction-speed characteristic of a serial wheel loader is built taking into account the constant power of the drive internal combustion engine for rotation of the axial- piston reversible adjustable transmission pump. The dependence of the torque on the wheel hub of the loader depending on its speed was analyzed. The selection of a high-torque radial-piston hydraulic motor of multi-cycle action, which satisfies the parameters of the transmission in terms of torque and maximum rotation frequency and does not have an intermediate gearbox on the hub, has been made. To reduce the set power of the drive motor of the loader pump and fuel consumption, the hydraulic motors of the transmission are also equipped with a two-stage regulator for changing the working volume. Constructed block diagrams in the VisSim application program package for the solution of nonlinear differential equations for determining the speed of the loader, the pressure in the hydraulic drive and its useful power. The results. The analysis of oscillograms of dynamic processes in the hydraulic drive of the loader showed that by means of modeling the pump supply modes and step change of the working volume of the multi-cycle radial piston hydraulic motor, it is possible to detect extreme modes that lead to fluctuations in the speed and power of the loader, as well as pressure in the hydraulic drive.