Longitudinal continuous welding device for packaging machines

Longitudinal continuous welding device for packaging machines comprising:

• one supporting piece (1) for layers of material to be welded continuously;
• at least one ultrasonic welder (2) equipped with a sonotrode (21), and wherein the sonotrode (21) and the supporting piece (1) face each other horizontally, arranged on opposite sides of a longitudinal path along which the layers of material (M) to be welded continuously advance inside the packaging machine, wherein both the at least one ultrasonic welder (2) and the supporting piece (1) are unable to move in the direction of longitudinal movement of the layers of material (M);
• at least one positioning element (3) to arrange the welding device in a non-operating position, in which the sonotrode (21) of the welder and the supporting piece (1) remain distanced horizontally, or in an operating position for welding in which the sonotrode (21) and the supporting piece (1) are maintained very close to each other;
• and
• at least one elastic pusher (4), which acts on at least one of the ultrasonic welder (2) and the supporting piece (1) to push them against the opposite sides of the layers of material (M) to be welded continuously;
• wherein said at least one elastic pusher (4) is configured and arranged to enable the separation between the ultrasonic welder (2) and the supporting piece (1) to vary at a very high frequency, due to the action of the sonotrode (21), enabling the layers of material (M) to be welded to continuously advance through the space between the supporting piece (1) and the sonotrode (21) as these conduct the welding of the layers of material (M).