Patent ID: 8657182

Claim:
An ultrasonic welding device, comprising: a torsion sonotrode comprising two opposed end faces, a circumferential surface which surrounds a torsion axis and connects the opposed end faces, and working surfaces provided at a radial distance from the torsion axis, wherein annular surfaces are provided on the circumferential surface on two sides of the working surfaces and lie over a nodal line with respect to a wavelength of a natural vibration of the torsion sonotrode, wherein the torsion sonotrode is symmetrical about a plane of symmetry running perpendicular through the torsion axis, wherein at least one converter is coupled to one of the end faces of the torsion sonotrode to generate an ultrasonic vibration directed about the torsion axis, and wherein a pressure device is provided to generate a pressure on both of the annular surfaces acting substantially perpendicular to the torsion axis.