网络化高精度和高稳定性阵列电子胶带秤仪表

Networked high-precision and high-stability array electronic belt scale instrument

通过设计高灵敏秤体、提高称重传感器采样精度等提高电子胶带秤计量精度的传统方法很难补偿胶带张力引起的称重误差;而通过并行设置多个秤体、构成阵列秤的方式能够减小胶带张力对计量精度的影响。基于内力理论分析得出电子胶带秤首尾两端的胶带张力是造成称重误差的主要原因,且两端胶带张力占比随称重单元增多而变小,因此阵列电子胶带秤可改善胶带张力变化对计量精度的影响和稳定性。设计了以高性能ARM处理器STM32F767为控制核心的网络化高精度和高稳定性阵列电子胶带秤仪表,实现了8路称重阵列动态计量、逻辑控制、人机交互、掉电存储、工业控制与通信、互联网远程监控等功能。采用静态挂码方式对该仪表进行试验,结果表明该仪表的称重误差约为0.03%,且对胶带速度和载荷引起的张力变化不敏感,具有较高的计量精度和稳定性。

The traditional methods applied in improving the measurement accuracy of electronic belt scales are designing highly sensitive scales and improving the sampling accuracy of weighing sensor.These methods are difficult to compensate for the weighing errors caused by belt tension.However,the effect of belt tension on measurement accuracy can be reduced by setting up multiple scales in parallel and forming an array of scales.Based on the analysis of internal force theory,it is concluded that the belt tension at both ends of the electronic belt scale is the main cause of weighing errors,and the proportion of belt tension at both ends decreases with the increase of the weighing unit.Therefore,the array electronic belt scale can reduce the impact of belt tension changes on the measurement accuracy and improve stability.In this study,a networked high-precision and high-stability array electronic belt scale instrument is designed with high-performance ARM processor STM32F767 as the control core.The functions of the scale include 8-channel weighing array dynamic metering,logic control,human-machine interaction,power-down storage,industrial control&communication and Internet remote monitoring.By using static coding method,the test results show that the weighing error of the instrument is about 0.03%,the scale is insensitive to the tension changes caused by the belt speed and load,and the scale has high measurement accuracy and stability.