The ultrasounds are sound waves which propagate in any elastic means with frequencies higher than the ones the human ear can hear.
Ultrasonic welding occurs when a normal variable load is applied to the pieces to be welded and one part is vibrated against the other by a resonator stack consisting of the transducer, and the booster at the end of which the sonotrode is attached.
The sonotrode generates an ultrasound vibration between the parts. This intense vibration generates heat and consequently the thermoplastic materials melt, ensuring the part welding and assembly.
The ultrasonic generator provides a sinusoidal electrical waveform at a frequency of between 20 and 50 kHz. Sirius Electric builds systems with frequencies of 20 - 30 - 36 - 40 kHz.
The piezoelectric transducer converts electrical impulses into mechanical movement. The booster amplifies this movement and transfers it to the sonotrode which is brought into contact with the piece to be welded. Sonotrodes can be made from different materials and have the shape of the piece.
Particular attention is paid to the shape of the weld joint. They have the task of concentrating energy to permit a very fast welding cycle. Their shape and form are sized according to the application and material to be welded. If the weld joint is less than 6 mm from the area of contact with the sonotrode, it is called near field welding, while if it is further, it is far field welding.
Fixturings for ultrasound are made in-house using numerical control machine tools.
All of our ultrasound welders have cycle control using microprocessors. Welding cycles can have time, energy, and quantity control depending on the model.
Our ultrasound generators also have automatic frequency search and amplitude variation.
The production of standard welding machines, spans an extensive range, with various models that can adapt to the most diverse assembly problems.
The customer is always involved when manufacturing special welding machines. This way, the delivery creates a highly appreciated and positive result. Ultrasound welding is highly advantageous because it is rapid, reliable, and replaces certain assembly methods such as gluing and screwing. Ultrasound welders are used in many sectors such as the production of parts for the automotive and medical industries, for the production of technical articles, and for the electrical engineering industry.