基于红外二级管纠偏探头的设计与验证

Design and validate excursion sensor based on infrared diode

通过直流电路驱动红外二级管发出的红外光恒功率发射,红外光经过聚光透镜,形成直径为20mm的光柱。带材正常运动时处于光柱的中心位置,光电二极管接收到的光功率为一定值;当带材偏移时,引起接收管的光功率变化,导致光生电流变化,从而确定偏移量与光生电流的关系。在信号的放大与处理环节采用两级运算放大器相结合的电路,充分减少信号衰减与噪声影响,并产生较大的电压增益,试验表明该电路设计可行并达到一定的精度。

The infrared diode was droved by DC circuit to send light with constant power. The rays passed through a condensing lens and formed a light pole with the diameter of 20 mm. When the web worked normally, it passed through the central axle of the light pole so that the optical power received by photosensitive diode was normal constant. On the contrary, if the web went with excursion, different luminous flux would be gotten by the photosensitive diode. Furthermore, the photocurrent which had a direct proportion relationship with the luminous flux would be changed too. Based on the above, the relationship between the excursion and the photocurrent could be determined. Using two operational amplifiers to amplify and deal with the current signals, it could lessen the signal attenuation and yawp infections and produce biggish voltage plus. The experimental results shows that this designed circuit is available and with certain accuracy.