Patent ID: 7415881

Claim:
A sensor system for determining the position of two edges of at least two web materials traveling along a predetermined travel path, the sensor system comprising: at least one transmitter block disposed substantially adjacent the travel path and extending across at least a width of the at least two web materials, the at least one transmitter block having a plurality of transmitters, each transmitter being capable of selectively transmitting ultrasonic signals across at least a portion of the travel path upon receipt of a transmitter drive signal; at least one receiver block spaced a distance from the at least one transmitter block and extending across at least a width of the at least two web materials whereby the travel path passes in between the at least one transmitter block and the at least one receiver block, the at least one receiver block having a plurality of receivers being positioned to receive at least a portion of the ultrasonic signals transmitted by the plurality of transmitters of the at least one transmitter block, and the receivers being capable of generating receiver output signals responsive to the receivers sensing ultrasonic signals transmitted by the transmitters; and a master unit for periodically transmitting the transmitter drive signal to a selected transmitter of the transmitter block; wherein the master unit selectively toggles a selected one of the receivers in the receiver block to a first mode, wherein the selected receiver is permitted to form a receiver output signal responsive to the selected receiver sensing an ultrasonic signal, from a second mode, wherein all of the receivers in the receiver block are restricted from providing receiver output signals, the selected receiver corresponding to the selected transmitter and being toggled to the first mode in synchronization with the transmission of the transmitter drive signal to the selected transmitter; wherein the master unit receives receiver output signals and utilizes the receiver output signals to monitor the positions of two edges of the at least two web materials.