Optimization and experiment research of the cylinder block of the roller piston pump

Abstract

The roller piston pump is a new type of axial piston pump. The pump has the advantages of high limiting speed, low noise, and vibration compared to the traditional axial piston pump. However, the structure and flow channel of the cylinder block of the roller piston pump are more complicated. When the cylinder block is subjected to high hydraulic pressure, its radial compressive deformation is large, which will lead to wear of the cylinder block and distribution shaft. For this problem, the paper will optimize the structural parameters of the cylinder block. Eight key parameters of the cylinder block are selected as the design variables, and the maximum radial deformation and mass of the cylinder block are taken as the optimization objectives. The central composite design method is used to generate 81 sets of sample data, and the second-order response surface model is obtained by regression analysis. The optimal structural parameters of the cylinder block are obtained through multi-objective optimization, and the material of the cylinder block is optimized. Finally, an experiment bench was built for experimental validation, and the efficiency of the pump was further investigated. The optimization results show that the maximum compression deformation of the inner diameter surface of the cylinder block decreases from 15.865 to 4.903 µm, and the mass of the cylinder block increases from 434.951 to 489.892 g. The experimental results show that the load-bearing pressure of the optimized roller piston pump increases from less than 15 to 35 MPa, and compared with the traditional axial piston pump, there is an increase in both mechanical efficiency and volumetric efficiency.