Ultrasonic sensor system for web-guiding apparatus
View Patent ↗A sensor system for determining the position of at least two edges 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 continuous 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 positions of at least two opposing edges of at least one web material traveling along a predetermined travel path, the sensor system comprising:
at least one transmitter block disposed substantially adjacent the travel path, the at least one transmitter block having a plurality of transmitters in a continuous staggered formation which formation has a length extending across at least an entire width of the web material between the two opposing edges, the transmitters 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 to define a continuous sensor field of view which extends across at least the width of the at least one web material 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, and wherein the master unit receives receiver output signals and utilizes the receiver output signals to monitor the positions of the at least two opposing edges of the at least one web material.
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 master unit receives receiver output signals and utilizes the receiver output signals to monitor the positions of at least two opposing edges of the at least one web material.
4. The sensor system of claim 3 , further comprising a means for determining a center position of the at least one web material by utilizing receiver output signals monitoring the positions of at least two opposing edges of the at least one web material.
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 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 at least one web material.
12. A method for measuring positions of at least two opposing edges of at least one web material traveling along a predetermined travel path, the method comprising the steps of:
positioning the at least one web material in a continuous sensor field of view of an ultrasonic sensor system such that the at least two edges of the at least one web material are disposed within the continuous sensor field of view, the continuous sensor field of view being formed by a plurality of spaced apart transmitters and receivers, the transmitters in a first continuous staggered formation, the receivers in a second continuous staggered formation which first and second staggered formations have lengths extending across at least an entire width of the at least one web material between the two opposing edges and whereby the travel path of the web material passes in between the first and second continuous staggered formations; and
determining the positions of the at least two opposing edges of the at least one web material by analyzing output signals generated by the receivers receiving ultrasonic signals from the transmitters.
13. The method of claim 12 , comprising the additional steps of scanning, via a master unit, the continuous sensor field of view to locate at least two opposing edges of the at least one web material.
14. The method of claim 12 , comprising the additional step of determining a center position of the at least one web material by analyzing receiver output signals monitoring the at least two opposing edges of the at least one web material.
15. The method of claim 12 , comprising the additional step of determining a width of the at least one web material by analyzing receiver output signals monitoring the at least two edges of the at least one web material.
16. The method of claim 12 , wherein a master unit of the ultrasonic sensor system periodically transmits transmitter drive signals to selected transmitters within a logical web section defined by the at least two edges of the at least one web material.
17. The method of claim 12 , wherein in the step of providing at least one web material, the at least one web material is provided at any position within the continuous sensor field of view.