The complete ultrasonic welding system is composed of active and passive components. The active components generate the vibrations, transfer them, and apply them into the weld parts The passive components absorb the resulting forces, maintain the parts in position, and particularly support the weld joint.
The converter, booster, and sonotrode are combined to form what is referred to as stack.
The fully digital ultrasonic generator uses the supply voltage to generate high voltage in the respectively required ultrasonic frequency. All data relevant for the weld process are precisely measured and analyzed. The generator protects the vibrating system from overload, keeps the amplitude (tool movement) at a constant level, and compensates for the changing vibrating behavior of different weld tools.
The converter represents the interface between the electrical and the mechanical area. Utilizing the inverse piezoelectric effect, it converts the electrical oscillation to mechanical longitudinal vibration and transfers it to the booster or the sonotrode.
The amplitude transformer, often referred to as booster, increases or reduces the amplitude coming from the converter. Being suspended at nodal plain, the booster can also be used for vibration-free support of the stack in the ultrasonic welding machine and for transmission of forces.
The sonotrode being the actual active weld tool, transmits the mechanical vibrations into the part; i.e. it launches the ultrasonic vibration. Depending on its design geometry, the sonotrode can either increase or reduce the amplitude.
The stack is always adapted and optimized with regard to the plastic material and the geometry of the part’s contact.