Apparatus and method for ultrasonic bonding of a moving web

Apparatus for ultrasonically bonding a web of bondable material, comprising:

• web transport means for moving the web along a web travel path;
• the web transport means comprising a rotatable drum having an outer cylindrical surface, means for rotating the drum, and means for feeding the web onto the outer cylindrical drum surface at a first position, and for removing the web from the outer cylindrical drum surface at a second position circumferentially spaced-apart from the first position, whereby the segment of the drum surface between the first and second position defines the web travel path;
• a plurality of ultrasonic bonding means having respective sonotrode bonding surfaces and disposed along the travel path;
• means for energizing the ultrasonic bonding means;
• and
• carrier means for selectively moving the ultrasonic bonding means into intermittent bonding contact with the web during movement of the web along the travel path, the carrier means comprising a plurality of horn rolls, each horn roll having an outer carrier surface at which a respective sonotrode bonding surface is disposed, each outer carrier surface being positionable relative to the surface of the drum so as to bring the sonotrode bonding surface into bonding contact with a web carried on the outer cylindrical drum surface between the first and second positions thereof, and means to rotate the horn rolls to bring the sonotrode bonding surface into the bonding contact position;
• such that the web is multiply ultrasonically bonded during travel along the travel path by at least one of:
• (i) successive bonding contacts with a bonding site on the web by different ones of the plurality of ultrasonic bonding means, and (ii) simultaneous bonding contacts with a plurality of diffferent web bonding sites by different ones of the ultrasonic bonding means.