数字式转速测量仪

数字式转速测量仪(中文2200字,英文1700字)
1 转速测量仪原理
本测速仪的测速敏感器件采用红外线传感器，由专门的探测装置发射红外线，同时接受从被测物体反射回来的红外线，通过光电转换变为电脉冲信号，不影响物体的转动。发射管和接受管都固定在探测架上，通过透镜聚焦，半透明膜既能使反射的红外光线射向转动物体，又能使由转动物体反射回来的红外线通过半透明膜射向接受管。在转动体上沿圆周均匀贴上若干反射纸，它能定向反射红外线，使接受管接受到反射回来的红外线。
光电转换原理见图1。在光电三极管3DU5C上加一适当偏压，当3DU5C受红外线照射时，处于导通状态，A点为低压电平，3DG6截止，B点为高电平；当没有红外线照射时，光电三极管截止，A点呈现高电平，使3DG6集电极B点为低电平，B点的脉冲信号经过反相器1、2的整形，再经门3反相，便得到频率与转速大小相应成比例变化的转速脉冲信号。转速脉冲信号送入8032单片机的定时/计数器，经过单片机的软件处理计算出转速。
 
Digital Meter for Measuring Rotational Speed
The rotor speed control system of industry is one of the important parameters. Mechanical tachometer measuring speed, the rotor contact with the measured object must be to get the synchronous speed, through the internal gear shift instruction after the pointer speed with the size of the header. Use of mechanical tachometer measured object can interfere with movement, especially when measured rotor mass is very small, speed tables on the rotor pressure is not a small additional load, which affects the measurement accuracy. This paper describes a 8032 single-chip microcomputer as the core to the non-contact Digital Tachometer.