DEVICE AND METHOD FOR FORMING ULTRASONIC WELDS ON WEB MATERIALS IN CONTINUOUS MOVEMENT

摘要

Apparatus for forming transversal welds on a composite web material, comprising at least two superimposed sheets of material, suitable for use in the production of sanitary articles, comprising: a feeding unit including first and second feeding means configured to advance the composite web along a main straight direction X at a speed V1. an ultrasonic welding unit 80 arranged between the first and second feeding means, comprising at least one ultrasound source coupled to a sonotrode having a flat welding surface and an anvil unit having at least one anvil element movable along a closed path, which has a straight portion parallel to the main direction X.

主权项

1. An apparatus for the ultrasonic transverse welding of a composite web comprising at least two superimposed sheet materials, comprising:
a feeding unit including first and second feeding devices configured to advance said composite web along a main direction at a speed; and an ultrasonic welding unit arranged between said first and second feeding devices and comprising:
at least one ultrasonic generator coupled to a sonotrode having a flat welding surface parallel to the plane of movement of the web and fixed in said main direction; andan anvil unit having at least one anvil element movable along a closed path having a straight portion parallel to said main direction, said at least one anvil element moving at said speed along said straight portion of said closed path, wherein, during use, said at least one anvil element is pressed against said flat welding surface with the interposition of said composite web material with a predetermined force, and wherein said at least one anvil element and said flat welding surface have an extension in a transverse direction to said main direction that is equal to or greater than the length of said transverse weld and said flat welding surface has a total length parallel to the main direction between 0.1 and 1.0 meters, more preferably between 0.4 and 0.6 meters.