针对目前存在的内螺纹人工检测工作量大的问题, 采用基于单片机技术的涡流方法研制了一种智能螺纹检测仪。先设计了一个简单的阻抗测量电路,建立了探头对不同螺纹状态试样和试验频率的阻抗图, 然后通过分析该阻抗图找出了适合于用幅度法检测的频率范围,最后通过对探头施加合适的正弦激励信号, 用测量探头两端电压的方法完成螺纹检测。对给定的螺纹试样检验结果表明, 该仪器可以准确地判断出试样的半牙、无牙和合格状态, 并能给出相应的输出信号。

Aiming to solving problems existing in previous internal thread inspection method by hand such as large amount of work, an intelligent thread inspection instrument is developed using single chip technology based on eddy current method. First impedance diagram of the probe to the thread state and test frequency is established by designing a simple impedance measuring circuit, and then through analyzing the impedance diagram, suitable amplitude detection frequency range is find out. At last, by adding an appropriate sine excitation signal to the probe and measuring ptobe ends voltoge to complete the thread inspection. Actual test results to a given sample show that the developed thread inspection instrument can accurately judge the thread state of half thread, no thread and full thread, and give a corresponding output signal.