Abstract: A method of manufacture comprising the following steps: (a) during a respective indexing portion of a respective work cycle, advancing a fastener tape made of flexible thermoplastic material along a process pathway, the fastener tape not advancing during a respective dwell time of the respective work cycle; (b) during each dwell time, forming or attaching a respective structural feature of a type on the portion of the fastener tape that is resident at a first fixed station situated along the process pathway, the structural features of that type being spaced at intervals along the portion of the fastener tape that is downstream of the first fixed station; (c) while the fastener tape is advancing along the process pathway during the indexing portion of each work cycle, transmitting light toward a volume of space at a second fixed station, the process pathway intersecting and passing through the volume of space; and (d) photodetecting at least portions of the transmitted light after some or all of the transmitte

Abstract: A method of manufacture comprises the following steps: (a) advancing a fastener tape made of flexible thermoplastic material along a process pathway during an indexing portion of a work cycle, the fastener tape not advancing during a dwell time of the work cycle; (b) during each dwell time, deforming the fastener tape at a first fixed station situated along the process pathway; (c) transmitting light toward the fastener tape at a second fixed station while the fastener tape is advancing; and (d) photodetecting a portions of the transmitted light after some or all of the transmitted light has passed the fastener tape, the photodetected portions of the transmitted light being converted into electrical signals; wherein the distance of the fastener tape advanced in step (a) is determined in accordance with an algorithm that takes into account characteristics of electrical signals acquired in step (d) during earlier work cycles.

Abstract: A method of manufacture comprising the following steps: (a) during a respective indexing portion of a respective work cycle, advancing a fastener tape made of flexible thermoplastic material along a process pathway, the fastener tape not advancing during a respective dwell time of the respective work cycle; (b) during each dwell time, forming or attaching a respective structural feature of a type on the portion of the fastener tape that is resident at a first fixed station situated along the process pathway, the structural features of that type being spaced at intervals along the portion of the fastener tape that is downstream of the first fixed station; (c) while the fastener tape is advancing along the process pathway during the indexing portion of each work cycle, transmitting light toward a volume of space at a second fixed station, the process pathway intersecting and passing through the volume of space; and (d) photodetecting at least portions of the transmitted light after some or all of the transmitte

Abstract: Methods and apparatus for stretching a plastic tape before the tape is joined in proper registration to a web of material in a machine. The apparatus comprises: means for advancing a leading portion of a flexible tape along a tape pathway; a guide that guides a lagging portion of the tape; a brake mounted to the guide and activatable to clamp a portion of the lagging portion of the tape at a first location; a sensor mounted to the guide and arranged to output a characteristic signal whenever the passage of a boundary of a structural feature of a particular type, repeatedly formed on or attached to the tape, is detected at a second location upstream of the first location; and a controller for causing the leading portion of the tape to be advanced a predetermined distance at regular spaced intervals of time and for causing the brake to clamp the lagging portion in response to the output of the characteristic signal by the sensor.

Abstract: An apparatus for attaching discrete lengths of zipper at spaced intervals across a web of bag making film has an endless belt supported between a pair of pulleys for moving zipper segments into position on the web. The zipper segments are cut from a zipper supply and fed into a nip between the endless belt and the web top surface. After a zipper segment is deposited into position on the web, the endless belt is raised. A vertically movable sealing bar below the web is raised into position to heat the web to seal the zipper to the web after which the sealing bar is lowered. The web then advances and the process is repeated.

Abstract: A method and an apparatus for automatically feeding zipper assemblies (with or without sliders) to a station, for example, a station where the zipper assemblies are sealed to thermoplastic bag making film. The zipper tape feeding apparatus comprises a pair of endless belts that circulate in opposite directions and have confronting portions running along a straight pathway through which a zipper tape is passed. The first belt is driven intermittently by a motor and the second belt is free to circulate during frictional contact with the first belt. At least a portion of the zipper tape is sandwiched between confronting portions of the belts, being moved forward as the belts circulate. The belts are preferably made of rubber to minimize slippage of the zipper tape during feeding.

Abstract: A method and an apparatus for producing zippered bags at faster speeds. This is accomplished by speeding up the ultrasonic welding operation. More specifically, ultrasonic welding is performed continuously while the web of bag making film and the zipper tape are moving, instead of being performed while the film and zipper tape are stopped. To facilitate this improvement, the ultrasonic welding station is moved from the bag machine, where the bag making film and zipper tape move intermittently, to the sealer frame, where the film and zipper tape move continuously. The ultrasonic welding apparatus comprises a pair of rotary elements, one of which is acoustically coupled to an ultrasonic transducer. One of the rotary elements is provided with a protuberance on its periphery that acoustically couples the zipper tape to the energized rotary element.

Abstract: A method and an apparatus for automatically feeding zipper assemblies (with or without sliders) to a station, for example, a station where the zipper assemblies are sealed to thermoplastic bag making film. The zipper tape feeding apparatus comprises a pair of endless belts that circulate in opposite directions and have confronting portions running along a straight pathway through which a zipper tape is passed. The first belt is driven intermittently by a motor and the second belt is free to circulate during frictional contact with the first belt. At least a portion of the zipper tape is sandwiched between confronting portions of the belts, being moved forward as the belts circulate. The belts are preferably made of rubber to minimize slippage of the zipper tape during feeding.

Abstract: A method and an apparatus for producing zippered bags at faster speeds. This is accomplished by speeding up the ultrasonic welding operation. More specifically, ultrasonic welding is performed continuously while the web of bag making film and the zipper tape are moving, instead of being performed while the film and zipper tape are stopped. To facilitate this improvement, the ultrasonic welding station is moved from the bag machine, where the bag making film and zipper tape move intermittently, to the sealer frame, where the film and zipper tape move continuously. The ultrasonic welding apparatus comprises a pair of rotary elements, one of which is acoustically coupled to an ultrasonic transducer. One of the rotary elements is provided with a protuberance on its periphery that acoustically couples the zipper tape to the energized rotary element.

Abstract: An apparatus for attaching discrete lengths of zipper at spaced intervals across a web of bag making film has an endless belt supported between a pair of pulleys for moving zipper segments into position on the web. The zipper segments are cut from a zipper supply and fed into a nip between the endless belt and the web top surface. After a zipper segment is deposited into position on the web, the endless belt is raised. A vertically movable sealing bar below the web is raised into position to heat the web to seal the zipper to the web after which the sealing bar is lowered. The web then advances and the process is repeated.

Abstract: An apparatus for attaching discrete lengths of zipper at spaced intervals across a web of bag making film has an endless belt supported between a pair of pulleys for moving zipper segments into position on the web. The zipper segments are cut from a zipper supply and fed into a nip between the endless belt and the web top surface. After a zipper segment is deposited into position on the web, the endless belt is raised. A vertically movable sealing bar below the web is raised into position to heat the web to seal the zipper to the web after which the sealing bar is lowered. The web then advances and the process is repeated.

Abstract: An apparatus for attaching discrete lengths of zipper at spaced intervals across a web of bag making film has an endless belt supported between a pair of pulleys for moving zipper segments into position on the web. The zipper segments are cut from a zipper supply and fed into a nip between the endless belt and the web top surface. After a zipper segment is deposited into position on the web, the endless belt is raised. A vertically movable sealing bar below the web is raised into position to heat the web to seal the zipper to the web after which the sealing bar is lowered. The web then advances and the process is repeated.