基于电容传感器的毛细管粘度计液位自动检测方法

Automatic Liquid Level Detection Method for Capillary-Gravity Viscometer Based on Capacitance Sensors

针对现有毛细管粘度计液位手动计时检测方法的不足,设计了一种电容式液位传感器,提出了基于电容式液位传感器的毛细管粘度仪自动液位检测方法。通过实时跟踪电容量的变化,采用基于极大值判别的一阶差分阈值法自动判定计时起点和计时终点,实现毛细管粘度计的液位自动检测和自动读数,研制了智能粘度仪。结合实验结果,分析了电容式液位测量的误差因素并给出了去误差方法。智能粘度仪的实际应用表明,这种液位检测方法测量准确,抗干扰能力强,适用于重力式毛细管粘度计的液位自动检测。

An automatic liquid level detection method based on capacitance sensors is proposed. Based on threshold determination of the first order difference, the automatic detections of the timing point and the automatic readings of the liquid level for the capillary viscometer are realized by real-time tracking of capacitance changes. The measurement error factors are discussed and the correction methods are given. The experimental results show that the automatic liquid level detection method has merits of accurate measurement,strong anti-interference ability. And this gravity-capillary viscometer is suitable for the liquid level automatic detection.