To improve the precision and sensitivity of dynamic torque non-contact measurement, a differential torque sensor based on magneto-elastic effect of the amorphous alloy, and with a supporting ring was discussed. The principles and structure of the sensor were presented, and its output characteristic equation was derived. By experiments, the effects of the gap between the sensor probe and the shaft surface on sensor outputs were analyzed, and the best gap rang was got. A contrast analysis on the measurement accuracy and sensitivity was made in both testing cases of with and without an amorphous alloy thin strips on the shaft surfaces. Experimental results show that maximum no-linear error is 2.14% F·S, maximum repeatability error 1.54% F·S, the maximum sensitivity of 2.09mV/(N·m).

torque measurement, sensor, amorphous alloy, magneto-elastic effect

为了提高动态扭矩非接触测量的精度和灵敏度，对一种基于非晶态合金压磁效应的环形差动式扭矩传感器进行了研究。介绍了传感器的结构和原理，推导出了传感器的输出方程。通过试验，分析了这种扭矩传感器探头与轴表面的气隙对输出信号的影响，得出了最佳气隙范围。分别对轴表面附着和不附着非晶态合金层进行了动态转矩测量，对比分析了两种情况下的测量精度和灵敏度。试验显示，采用所设计的传感器，在轴表面附着非晶态合金层时，最大非线性误差为2.14% （满量程），最大重复性误差为1.54%（满量程），最大灵敏度为2.09mV/(N·m)。

扭矩测量, 传感器, 非晶态合金, 压磁效应