| 摘要 |
An adhesive dispensing apparatus for applying continuous, parallel adhesive beads onto the center portion of a substrate and intermittent, parallel adhesive beads on the outer portions of a substrate, particularly the plastic backing sheet of a disposable diaper. The apparatus includes a slot nozzle, divided into two center sections and two end sections, which is formed with flow passageways for each section having a coat hanger profile including a plurality of spaced, discharge orifices to form the parallel beads. A valving arrangement including solenoid-operated center dispensing valves for each center section of the nozzle, and solenoid-operated dispensing and recirculation valve pairs for each end section of the nozzle, controls the flow of adhesive to the nozzle. The center dispensing valves are continuously opened during an operating run to apply continuous adhesive beads on the center portion of the substrate, and the outer dispensing valves are opened and closed intermittently to form gaps on the substrate without adhesive where the leg holes of the diaper are cut. When the outer dispensing valves are closed, the recirculation valves are simultaneously opened to maintain constant adhesive flow to the center dispensing valves.
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