Ultrasonic sensor system for web-guiding apparatus
View Patent ↗A sensor system for determining the position of at least one edge of at least one web material traveling along a predetermined path. In one embodiment, the sensor system has at least one transmitter block having a plurality of transmitters capable of selectively transmitting ultrasonic signals and at least one receiver block having a plurality of receivers capable of generating receiver output signals in response to the receivers receiving at least a portion of the ultrasonic signals transmitted by the at least one transmitter block. The receiver block is spaced a distance from the transmitter block so as to define a sensor field of view therebetween whereby at least a portion of the at least one web material traveling along a predetermined travel path interferes with at least a portion of the ultrasonic signals transmitted by the at least one transmitter block. The receiver output signals generated by the at least one receiver block is indicative of the position of the web of material as the same is moved along the travel path between the transmitter block and the receiver block. In an alternative embodiment, the functions of the at least one transmitter block and the at least one receiver block are performed essentially equivalently by at least one transceiver block and at least one reflector.
1. 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.
2. The sensor system of claim 1 , further comprising a means for determining a transition between two or more web materials.
3. The sensor system of claim 1 , wherein the receivers of the at least one receiver block are positioned in a staggered formation so as to prevent formation of gaps in the reception of ultrasonic signals across at least one of a length or a width of the at least one receiver block of the sensor system.
4. The sensor system of claim 1 , wherein the selected receiver is selectively toggled from the second mode to the first mode to permit the selected receiver to receive the ultrasonic signal generated by the selected transmitter, and then the selected receiver is automatically toggled back to the second mode after a predetermined time.
5. The sensor system of claim 1 , wherein each transmitter of the at least one transmitter block transmits ultrasonic signals at a different time than an adjacently disposed transmitter.
6. The sensor system of claim 1 , wherein a predetermined group of transmitters of the at least one transmitter block transmits ultrasonic signals at a different time than an adjacently disposed predetermined group of transmitters.
7. The sensor system of claim 1 , wherein each receiver of the at least one receiver block is paired with at least one corresponding transmitter of the at least one transmitter block and receives ultrasonic signals at a frequency substantially equal to the frequency transmitted by the at least one corresponding transmitter.
8. The sensor system of claim 1 , wherein transmitters of the at least one transmitter block transmit ultrasonic signals at a different frequency than adjacently disposed transmitters.
9. The sensor system of claim 1 , wherein a predetermined group of transmitters transmit ultrasonic signals at a different frequency than an adjacently disposed predetermined group of transmitters.
10. The sensor system of claim 1 , further comprising means for sensing an environmental temperature surrounding at least a portion of the sensor system, and for enhancing the receiver output signals with at least one stored temperature compensation value so as to generate a sensor output signal in which changes in the environmental temperature no longer have a substantial effect on the nature of the sensor output signal.
11. The sensor system of claim 1 , further comprising a means for selectively actuating at least one of the transmitters within a predetermined range of at least one edge of the two webs of material.