SONOTRODE

摘要

A sonotrode (1) comprising: a head (15) which defines a sealing surface (14) elongated along a first direction (A); and a first and a second drive unit (12) distinct from one another, each comprising at least one piezo - electric element (13); wherein first and a second drive unit (12) may be electrically fed by an unique generator so as to cause the oscillation of head (15); the height (H) of head (15) measured along a second direction (B) transversal to sealing surface (14) being substantially equal to the half of the wavelength of the wave oscillating in the direction of second direction (B); sonotrode (1) further comprises: at least one slot (23) which extends through head (15) transversally to first and second direction (A, B); at least a finite number of nodal points (20) at which the amplitude of the oscillation of head (15) is substantially equal to zero; and a plane (P) on which at least some of nodal points (20) lie and which divides head (15) in a first portion (21) and in a second portion (22); the slot (23) being at a certain distance by plane (P).