Design And Research On The Low-speed Large-torque Emulsion Motor With Self-banlanced High-low Pressure Distributing Valves

Low-speed large-torque hydraulic motor as an important execute actuators in hydraulic system, due to its characteristics which can directly drive load, compact structure, short time of starting and braking, is widely used in engineering machinery. At Present, on account of mineral oil inflammable, serious pollution and dangerous work environment, it is urgent to research and develop the high water based low-speed large-torque motor. Existing motor and technology can not meet the requirement of high pressure, low speed and large torque operation.For the requirements and feature of high-pressure low-speed and large-torque mining motor, a radial swing cylinder emulsion motor with self-balanced high-low pressure distributing valve groups is put forward and investigated. The structure of radial swing cylinder is adopted in this motor, and the rubbing pair between piston and crankshaft is designed with static pressure support structure. Using the new distributing structure of self-balanced high-low pressure distributing valve group in the motor to solve the abrasion and leakage problem caused by the valve plate in traditional water motor. The emulsion motor with self-balanced high-low pressure distributing valve groups is suitable for high pressure low speed system and can run in double-way rotation.Firstly, the basic structure of low-speed large-torque emulsion motor designed is introduced. The structure of radial swing cylinder motor is adapted. Assignment principle of self-balanced high-low pressure distributing valve groups collocated symmetrically is highlighted. Kinematics and mechanics of both plunger and valve element are analyzed. Instantaneous displacement, torque, rotate speed and pressure fluctuations are investigated.Secondly, volume and speed fluctuations of motor is considered, and then the object function and the constraint condition are confirmed. Optimal solution of the structure parameters is gained through the fmincon function of MATLAB.The structure of valve chamber is optimized consider of the volume and Reynolds number, and the parameterization model is built through the software Pro/E, and flow fields inside the valve with different openings are simulated and analyzed using the computational fluid dynamics software named Fluent, that all proved the feasibility of the optimal solution.Finally, dynamic characteristics of emulsion motor is modeled and simulated by using software named AMESIM. The influence of several factors for different openings of valve, inlet rate of flow, moment of inertia and load are analyzed separately.The low-speed large-torque motor investigated in this paper is of generality, which is suituable with all actuating medium of high water base. The works accomplished and the conclusions obtained above can provide the basis for the further study on the lowspeed large-torque emulsion motor.