LVDT传感器仿真电路的设计与研究

LVDT(Liner Variable Differential Transformer)传感器是一种差动式变压器,用于将机械位移信号转换成电信号,具有灵敏度高、线性度好、分辨率高、寿命长及可靠性高等优点,在航空领域有着广泛的应用。由于LVDT传感器的输出信号为差分信号,传统的仪器仪表不能直接模拟LVDT传感器的信号,所以研制LVDT传感器仿真器替代真实的LVDT传感器,用于飞机机载系统的地面调试和试验。     

Sensor design and evaluation for on-machine probing of extruded tool joints

This paper describes the design and evaluation of two contact probes used to measure the length and bore concentricity of cylindrical, extruded tool joints while clamped in a production lathe spindle. The probes consisted of an LVDT, a spring-preloaded shaft supported by linear bearings used to isolate the LVDT from side loads, and a hardened steel sphere to contact the rough surface. For bore concentricity measurements, a parallelogram leaf-type flexure and 45° surface was used to transfer radial deviations to the spindle/part/LVDT axis. The LVDT output was used in conjunction with the lathe turret position to determine the extruded part dimensions prior to machining. Experimental results are provided for measurements of multiple parts; variations in length, internal diameter, and bore concentricity are compared to the nominal dimensions. Additionally, a calibration artifact is described which enabled evaluation of the measurement accuracies for the two probes. Given the pre-machining part dimensions, it is shown how this information can be used to select from a pre-defined matrix of part programs to reduce cycle time and machining cost.     

差动变压器式大量程精密角位移传感器的设计

设计了一种基于差动变压器原理的大量程精密角位移传感器。阐述了差动变压器式角位移传感器的工作原理,指出了传统传感器的不足。通过衔接法,既扩大了传感器的量程,又提高了传感器的精度。最大量程为±145°,精度可达1%。同时,采用多种温度补偿措施,改善了传感器的工作特性。     

WY-Ⅱ型存贮式电子流量计专用传感器的研制

差动变压器式位移传感器因其具有结构简单、灵敏度高、线性度好和测量范围宽等优点在工业中被广泛应用,但普通的传感器只适用于常温常压。WY—Ⅱ型存贮式电子流量计专用传感器是在传统差动变压器的基础上,重新设计研制的专门为在深油井下工作的新型传感器,具有耐高温高压、低电压、低功耗的特点。试验结果表明该传感器能在深井的复杂环境中稳定工作。     

LVDT数字智能变送器设计与实现

针对差动变压器式位移传感器(LVDT)应用中存在的线性度不够好、智能化程度不够高的问题,从软硬件设计层面,考虑了系统的可靠性、稳定性和灵活性。从应用层面,评估了测量数据的精度、线性度、可溯源性和长期稳定性的需求,设计了一种采用集成化LVDT模拟前端的软硬件一体的数字智能变送器。创新性的设计保证了EEPROM存储的多组标定数据和拟合系数,可对应不同量程或品牌的LVDT,且更换LVDT不影响变送器输出正确的位移值。系统能够在不重新标定的情况下,根据精度需求重新计算拟合系数。实际应用表明,该变送器适用于高精度、高可靠性要求的工业应用场合。     

LVDT位移传感器在伺服阀测试中的应用

为了克服实际伺服阀动态测试时,动态缸平衡位置偏移的问题,介绍了采用差动变压器原理(LVDT)位移传感器完成动态缸的位置检测,实现位置闭环控制的应用方式;分析了差动变压器(LVDT)位移传感器的工作原理、结构特点和信号处理要求;阐述了采用ICL8038信号发生器芯片产生LVDT的激励电压,应用AD630芯片实现LVDT位...     

基于PCI-76C2多功能卡的RVDT信号分配器的设计与实现

数字式电传飞控一般采用四余度或六余度RVDT,即每个操纵面由四个或六个独立的、相互隔离的RVDT组成,一个共用的工作杆与驾驶杆、脚蹬或舵面作动器相连。基于PC机和PCI-76C2多功能卡组成RVDT采集与仿真系统,实现RVDT信号分配器功能。在不破坏机载ACE系统连接完整性及不影响其测量信号质量的前提下,要将多余度RVDT中的每个输出电信号复制两份然后以两路模拟输出,一路仍继续接入ACE系统,另一路则需引入地面驾驶杆模拟操纵试验系统中。这样,试验进行时,同一个RVDT信号源能被两个系统同时采集;试验结束后,ACE系统又能够快速恢复原状。     

Experimental Investigation of the Deformation of Helical Gears with Double－Circular－Arc Tooth Profile Using Linear Variable Differential Transformer

ＥｘｐｅｒｉｍｅｎｔａｌＩｎｖｅｓｔｉｇａｔｉｏｎｏｆｔｈｅＤｅｆｏｒｍａｔｉｏｎｏｆＨｅｌｉｃａｌＧｅａｒｓｗｉｔｈＤｏｕｂｌｅ－Ｃｉｒｃｕｌａｒ－ＡｒｃＴｏｏｔｈＰｒｏｆｉｌｅＵｓｉｎｇＬｉｎｅａｒＶａｒｉａｂｌｅＤｉｆｆｅｒｅｎｔｉａｌＴｒａｎ...     

基于LVDT信号注入的力纷争试验方法研究

介绍了力纷争现象产生的原因以及力纷争试验的目的、要求,提出了一种基于LVDT信号注入的力纷争试验方法,并通过AMESim仿真分析验证了这种试验方法的可行性。此外,结合实际工程需要,研究了这种试验方法的具体实现方案。     

Volume change during the solidification of grey cast iron: its relation with the microstructural variation,comparison between experimental and theoretical analysis

The expansion/contraction during the solidification of grey cast iron was studied using Linear Variable Differential Transformer (LVDT). The experiments were conducted with and without melt treatment. Two types of inoculant used for melt treatment: ASSC (Si, Ca, Sr & Al) and MBZCAS (Si, Ca, Zr, Ba, Mn & Al). Microstructural investigations carried out to quantify the eutectic cells, undercooled graphite, primary austenite and secondary dendritic arm spacing (SDAS). It was found that the casting shows hardly any shrinkage during early solidification but in the eutectic region, the casting expands until the end of solidification. The measured and the calculated volume changes are close to one another, but the former shows more expansion. The addition of MBZCAS promotes more flake graphite, and ASSC does not increase eutectic cells much. In addition to that, it lowers the primary austenite fraction, promotes more eutectic growth, decreases undercooled graphite and SDAS. As a result, the volume expansion changes in the eutectic region.