Ultrasonic sensor for web-guiding apparatus

摘要

A sensor system for determining the position of at least one edge of a web of material is provided. The sensor system includes a transmitter and a receiver disposed on opposite sides of the web. The transmitter is capable of selectively transmitting ultrasonic signals, and the receiver is capable of receiving such ultrasonic signals and generating output signals indicative of the position of the web. The sensor system further includes a sensor drive circuit adapted to periodically transmit to the transmitter a transmitter drive signal representative of substantially one cycle of a signal, and to receive signals from the receiver with each signal being indicative of the position of the web.