At present, the domestic torque wrench testing methods mainly use simple testing equipment, relying on manual loading, which has the problems of low precision, simple function and low efficiency. Foreign special torque testing equipment can achieve high detection efficiency, but it is very expensive and difficult to maintain and expand. The above factors seriously affect the production and inspection of torque wrench.

现代测控技术中，智能仪器、总线仪器和虚拟仪器等微机化测控仪器，都是充分利用计算机的软件和硬件优势，既增强了参数测量、处理功能，义提高了性能指。根据上述理念，利用改进后的机械加载部分融合现代计算机技术，设计了扭矩自动测试系统。

In modern measurement and control technology, intelligent instruments, bus instruments, virtual instruments and other computerized measurement and control instruments make full use of the advantages of computer software and hardware, which not only enhances the function of parameter measurement and processing, but also improves the performance. According to the above concept, the torque automatic test system is designed by using the improved mechanical loading part and modern computer technology.

作为一台测量检定仪器，其重要的指标为测量精度。周围环境以及系统自身产生的噪声对微弱电信号干扰较大。硬件方面，通过合理布线、信号屏蔽措施以及滤波电路消除大部分噪声的影响；软件方面，通过大量试验，采取了合适的采样频率和滤波方法，使信号稳定的同时确保了必要的灵敏度

As a measurement and verification instrument, its important index is measurement accuracy. The noise generated by the surrounding environment and the system itself has great interference on the weak electrical signal. In terms of hardware, most of the influence of noise is eliminated by reasonable wiring, signal shielding measures and filtering circuit; In terms of software, through a large number of experiments, the appropriate sampling frequency and filtering method are adopted to make the signal stable and ensure the necessary sensitivity

预置式扭矩扳手在使用过程中，达到预没值之后，出现短暂打滑卸力并发出警报声，此后扳手会成为一个死角，相当于呆扳手。根据上述特性，检测时先自动加载并实时测量扭矩值，一旦测出_r峰值，就停止加载，记录峰值，再卸力。因而可以根据以上过程实现多次自动测试。

In the process of using the preset torque wrench, when it reaches the preset value, it will slip for a short time and release the force and give an alarm. After that, the wrench will become a dead angle, which is equivalent to a solid wrench. According to the above characteristics, the torque value is automatically loaded and measured in real time_ R peak, stop loading, record the peak, and then unload the force. Therefore, the automatic test can be realized many times according to the above process.

判断扳手是否合格，就是通过比较扳手预设值与所测得峰值。示值式扭矩扳手在使用范围内加载时，实时显示扭矩值，不会出现打滑卸力，因而示值式扳手不出现峰值。因为系统有延迟，无法在到达目标扭矩值时精 确停止，此外根据检定规程，测试时扭矩值由低到高单向加载。

To judge whether the wrench is qualified or not is to compare the preset value of the wrench with the measured peak value. When the indicator type torque wrench is loaded in the range of use, the torque value is displayed in real time, and there is no slipping unloading force, so the indicator type torque wrench does not have a peak value. In addition, according to the verification regulation, the torque value is loaded unidirectionally from low to high.

所以采取如下方式：先自动加载至略低于目标值的一个扭矩值，再通过手动控制微调至目标值，记录值后自动卸力。因而可以根据以上过程实现多次自动测试。判断其合格与否，就是在扭矩加载至目标值后比较扳手显示值与目标值。对于某些特殊扳手的检定还需要测量其与扭矩相应的转角，因此测试中还需测量扳手的转角。

Therefore, the following methods are adopted: first, automatically load to a torque value slightly lower than the target value, then fine tune to the target value through manual control, record the value and then automatically release the force. Therefore, the automatic test can be realized many times according to the above process. To judge whether it is qualified or not is to compare the wrench display value with the target value after the torque is loaded to the target value. For the verification of some special spanners, it is necessary to measure the angle corresponding to the torque, so it is also necessary to measure the angle of the spanner in the test.