Abstract: A method and system for determining the lateral position of an edge of a web are disclosed. The system includes an array of light transmitting elements and a corresponding array of lenses and an array of light receiving elements and a corresponding array of lenses. The light transmitting elements are each paired with a light receiving element and the light transmitting elements each transmit a beam of light energy towards the corresponding receiving element. The beams of light can be occluded by a web passing between the transmitting elements and the receiving elements, thereby reducing the light received by the receiving elements. The receiving elements can generate a signal that is proportional to the amount of they receive, and a controller can be used to determine the lateral position of an edge of the web in response to the signals generated by the receivers. A compensation light beam can be employed to enable the controller to compensate for several factors that can affect measurement accuracy.

Abstract: A method and system for determining the lateral position of an edge of a web are disclosed. The system includes a plurality of optical transmitters, a plurality of optical receivers, a plurality of ultrasonic transmitters, a plurality of ultrasonic receivers, and a controller. The controller is used to determine which type of transmitter and receiver should be used in conjunction with the specific web to be processed. The controller activates certain optical transmitters and determines the amount of optical occlusion that results from the web being between the optical transmitters and receivers. The controller also activates certain ultrasonic transmitters and determines the amount of sound occlusion that results from the web passing between the ultrasonic transmitters and receivers. The type of transmitter/receiver that results in the most occlusion can then be selected to determine the position of the edge of the web.

Abstract: A method and system for determining the lateral position of an edge of a web are disclosed. The system includes a plurality of optical transmitters, a plurality of optical receivers, a plurality of ultrasonic transmitters, a plurality of ultrasonic receivers, and a controller. The controller is used to determine which type of transmitter and receiver should be used in conjunction with the specific web to be processed. The controller activates certain optical transmitters and determines the amount of optical occlusion that results from the web being between the optical transmitters and receivers. The controller also activates certain ultrasonic transmitters and determines the amount of sound occlusion that results from the web passing between the ultrasonic transmitters and receivers. The type of transmitter/receiver that results in the most occlusion can then be selected to determine the position of the edge of the web.

Abstract: A method and system for determining the lateral position of an edge of a web are disclosed. The system includes an array of light transmitting elements and a corresponding array of lenses and an array of light receiving elements and a corresponding array of lenses. The light transmitting elements are each paired with a light receiving element and the light transmitting elements each transmit a beam of light energy towards the corresponding receiving element. The beams of light can be occluded by a web passing between the transmitting elements and the receiving elements, thereby reducing the light received by the receiving elements. The receiving elements can generate a signal that is proportional to the amount of they receive, and a controller can be used to determine the lateral position of an edge of the web in response to the signals generated by the receivers. A compensation light beam can be employed to enable the controller to compensate for several factors that can affect measurement accuracy.

Abstract: A method and system for determining the lateral position of an edge of a web are disclosed. The system includes an array of light transmitting elements and a corresponding array of lenses and an array of light receiving elements and a corresponding array of lenses. The light transmitting elements are each paired with a light receiving element and the light transmitting elements each transmit a beam of light energy towards the corresponding receiving element. The beams of light can be occluded by a web passing between the transmitting elements and the receiving elements, thereby reducing the light received by the receiving elements. The receiving elements can generate a signal that is proportional to the amount of they receive, and a controller can be used to determine the lateral position of an edge of the web in response to the signals generated by the receivers. A compensation light beam can be employed to enable the controller to compensate for several factors that can affect measurement accuracy.

Abstract: A method and system for determining the lateral position of an edge of a web are disclosed. The system includes an array of light transmitting elements and a corresponding array of lenses and an array of light receiving elements and a corresponding array of lenses. The light transmitting elements are each paired with a light receiving element and the light transmitting elements each transmit a beam of light energy towards the corresponding receiving element. The beams of light can be occluded by a web passing between the transmitting elements and the receiving elements, thereby reducing the light received by the receiving elements. The receiving elements can generate a signal that is proportional to the amount of they receive, and a controller can be used to determine the lateral position of an edge of the web in response to the signals generated by the receivers. A compensation light beam can be employed to enable the controller to compensate for several factors that can affect measurement accuracy.

Abstract: A method and system for guiding a web of moving material is disclosed. The system includes a plurality of variable light sources that can project light onto the surface of the web. One light source or a combination of light sources can be selected to project light onto the web, and the wavelength of the light can be selected. A light detector receives light reflected from the surface of the web and generates a data signal in response to the light received. A controller can be used to analyze the reflected light to determine the position of the web of moving material. The system enables the lateral and/or longitudinal position of various types of webs to be efficiently and effectively determined based upon the position of a line, edge, or other mark disposed on the surface of the web.

Abstract: An ultrasonic transducer unit for web edge detection includes multiple transducer elements attached to a single sound conducting plate. The transducer elements are preferably piezoelectric disks, and the sound conducting plate is preferably formed of hollow glass microspheres in an epoxy matrix. Multiple transducer elements may be positioned on the sound conducting plate in various geometric arrangements. Transducer units in accordance with the present invention may be mounted in a web edge detector head, such that pairs of transmitting and receiving transducer elements face each other across a detection gap through which a web of material is passed. Individual transducer elements within each transducer unit are activated to transmit/receive an ultrasonic beam in a selected pattern to provide both web edge sensing and ultrasonic signal compensation for varying ambient conditions in the detection gap.

Abstract: The edge of a web of material is inserted in a gap in a detector head between an ultrasonic blockage transmitter and an ultrasonic blockage receiver such that the magnitude of the pulse of sound from the transmitter that is received by the receiver is related to the portion of the web that blocks the beam of sound and thereby the position of the edge of the web. A compensation transmitter and compensation receiver are mounted proximate to the blockage transmitter and blockage receiver and transmit similar sound signals across the gap but are unoccluded by the web. The output of the compensation receiver is detected and used to normalize the values of the signal received from the blockage receiver to compensate for the effect of transient changes in ambient conditions.

Abstract: The edge of a web of material is inserted into a gap in a detector head between an ultrasonic blockage transmitter and an ultrasonic blockage receiver such that the magnitude of the pulse of sound from the transmitter that is received by the receiver is related to the portion of the web that blocks the beam of sound and thereby the position of the edge of the web. The ultrasonic frequency of each pulse is preferably very high to provide a narrow beam. The second half of the electronic drive pulse to the transmitter is preferably 180.degree. out of phase with the first half of the pulse to reduce excessive ringing of the transmitter. A compensation transmitter and compensation receiver, which are mounted proximate to the blockage transmitter and the blockage receiver, transmit similar sound signals across the gap but are unoccluded by the web.

Abstract: A web aligning apparatus for use with multi-level web material such as carpeting, tufted fabrics and the like having a backing web and a pile on the backing web inwardly of a side edge of the backing web. The web aligning apparatus includes a pile engaging member mounted at a sensing location along the course of travel of the web for movement along a first path crosswise of the course of web travel and generally parallel to the face of the web at the sensing location to sense lateral deviations of the course of travel of the pile edge from a preselected position. The pile engaging member is also mounted for movement along a second arcuate path generally tangent to the web from a first position extending alongside the web backing at the sensing location toward a second position displaced along the arcuate path in the direction of travel of the web when the pile engaging member rides onto the pile.