膜片式液压微位移执行器设计与特性分析

Design and Characterization of a Diaphragm-type Hydraulic Micro-displacement Actuator

微位移执行器是实现高精度控制的关键装置,广泛应用于精密伺服系统、芯片生产以及超精密加工领域。针对传统微位移执行器结构复杂、输出力小、行程短等问题,提出基于帕斯卡原理的膜片式液压微位移执行器。首先,建立了复合载荷下执行器的力学模型,并采用逐次修正法推导了应力-应变的迭代求解式。其次,研究了执行器关键参数对执行器行程和应力的影响规律。在此基础上,建立了以材料强度和设计行程为约束的膜片式液压执行器的优化设计流程。最后,通过有限元仿真验证了执行器的驱动压力-位移特性、行程及负载能力。结果表明,执行器表现出良好的驱动压力-位移线性关系,此外其40μm/mm的伸长率远优于压电陶瓷。在4 MPa的驱动压力下,执行器可实现1 mm的行程,并提供最大10790 N的输出力,即使在外负载为5395 N时仍能保持0.5 mm的行程。

Micro-displacement actuators are crucial for high-precision control and find extensive applications in precision servo systems,chip production,and ultra-precision machining.To address the issues of complex structure,low output force,and short stroke in traditional micro-displacement actuators,a diaphragm-type hydraulic actuator based on Pascal's principle is proposed.First,a mechanical model for the actuator under composite loads is established,and an iterative stress-strain solution is derived using the successive correction method.Next,the effects of key actuator parameters on stroke and stress are analyzed.Based on this,an optimization design process is developed,considering material strength and design stroke as constraints.Finite element simulations validate the actuator's driving pressure-displacement characteristics,stroke,and load capacity.The results demonstrate that the actuator provides a linear drive pressure-displacement relationship and a significantly higher elongation of 40μm/mm compared to piezoelectric ceramics.At a drive pressure of 4 MPa,the actuator achieves a stroke of 1 mm and delivers a maximum output force of 10790 N,maintaining a stroke of 0.5 mm even under an external load of 5395 N.