内曲线液压马达低速稳定性机理分析

Low-speed Stability Mechanism Analysis of Cam Lobe Hydraulic Motor

作为一种低速大扭矩液压马达,多作用径向柱塞式内曲线液压马达被广泛用于绞车、挖泥船、掘进机等大型装备的回转驱动系统中。内曲线液压马达低速稳定性严重影响着主机的工作品质。通过耦合油液压缩性、摩擦副泄漏等因素,建立多作用径向柱塞式内曲线液压马达的动态特性仿真模型,并分析配流轴配合间隙、柱塞与缸孔配合间隙、等加速导轨曲线幅角分配对马达低速稳定性的影响。仿真结果表明,马达低速稳定性随着配流轴配合间隙及柱塞与缸体配合间隙的减小而提高;随着导轨曲线的零速区和等速区幅角占比的增大,马达低速稳定性呈“U”形趋势变化,当零速区和等速区的幅角占比分别为0.0833和0.25时,马达低速稳定性较优。

As a kind of low-speed and high-torque hydraulic motor,the multi-stroke radial piston cam lobe hydraulic motor is widely used in the rotary drive system of large equipment such as winches,dredgers,tunnel boring machines.The low-speed stability of the cam lobe hydraulic motor significantly affects the working quality of the whole equipment.Considering the compressibility of oil and the leakage of friction pairs,the dynamic simulation model of the cam lobe hydraulic motor is established.The influence of the fit clearance between the distributor and the cylinder,the fit clearance between the piston and the cylinder,and the angle proportion of the constant acceleration cam ring curve on the low-speed stability of the motor are analyzed.The simulation results show that the low-speed stability of the motor improves with the decrease of the fit clearance between the distributor and the cylinder as well as the piston and the cylinder.With the increase of the ratio of the angle of the zero-speed region and the constant-speed region of the cam ring curve,the low-speed stability of the motor changes in a"U"shape.When it is 0.0833 and 0.25,the motor has better low-speed stability.