互补谐振耦合型电磁式直线位移传感器

Inductive Linear Displacement Sensor with Complementary Resonant Coupling Units

针对当前电场式和光电式直线位移传感器在环境适应性方面以及电磁式直线位移传感器在精度方面的不足,开展了互补谐振耦合型电磁式直线位移传感器的研究。传感器主要由1个定尺和2个动尺组成,其中2个动尺完全相同,且对称地布置于定尺两侧,与定尺形成互补耦合。定尺包含激励线圈和感应线圈,分别产生激励磁场和输出感应信号;动尺也包含感应线圈,但该线圈的作用并非输出感应信号,而是与串联电容形成谐振,接收激励磁场后产生二次磁场,反作用于定尺。该传感结构使定尺上的感应线圈以互补方式直接耦合动尺上的磁场,且避免了动尺引线,从而有助于提高位移测量精度和保障传感器的环境适应性。文中介绍了传感器的基本结构、工作原理及仿真验证、样机及实验测试。传感器的样机实验表明:在较粗糙的装配条件下,其原始测量误差在300 mm范围内为-8~+5μm。

An inductive linear displacement sensor with complementary resonant coupling units was proposed in this paper, by taking into account shortcomings of electric-type and photoelectric-type linear displacement sensors in environmental adaptability or measurement accuracy.The sensor was mainly composed of a stator and two identical movers.The two movers were symmetrically arranged on both sides of the stator, forming a complementary coupling with the stator.The stator contained excitation coils and pickup coils, which generated magnetic field and output induction signals respectively.The movers also contained pickup coils, which were in series with resonance capacitors to generate a secondary magnetic field that reacted on the stator after receiving the excitation magnetic field, rather than output induction signals.The structure of this sensor made the pickup coils on the stator directly receive the magnetic field on the movers in a complementary way, and avoided using leading wires on the movers, which was helpful to improve measurement accuracy and ensure the environmental adaptability of the sensor.The basic structure, operation principle, simulation verification, prototype and experimental test of the sensor were introduced in this paper.The experimental results of the sensor prototype show that the original measurement error is-8~+5 μm in the range of 0~300 mm, even though the prototype was assembled roughly.