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Principles:

The ultrasonic generator converts high-frequency energy will be transferred to mechanical motion of same frequency through ultrasonic transducer, and then the mechanical motion can be transferred to the welding horn by amplitude modulator, which can adjust the amplitude. The welding horn will pass the absorbed heat to the junction of workpieces for welding. In this particular zone, vibration energy can be converted into heat through friction. Ultrasonic can not only be used to weld hard thermoplastic but also to process the textile and thin-film.

Ultrasonic welding technique

A. Welding 

The typical profile of a joint design for ultrasonic welding has two functions

1) Its shape of a groove and tongue eases positicning during assembly and maintains .In place the parts during the welding cycle.

2)The energy director in the joint concentrates the energy to a small ared suppiles at the same time the necessary material for an optional welding joint. Th eprofile of the joint area depends largely on the purpose of the application; it can therefore be shape quite differently. The settings of the machine, like welding pressure and amplitude, are adjustd to produce a movement of the horn front in phase with the part to be welded. The second part  placed in the fixture must stay passive. The motional interference produces friction in the contact area of the two parts. Due to this highly intensive ultrasonic vibration the joint area melts together immediately. Under the pressure applied simultaneously and some friction of a second longer than the ultrasonic impulse lasts the melted area solidifies and inseparable joint is produced.

B. Riveting

Ultrasonic riveting is used to assemble injected plastic parts of another material .Studs on the molded plastic part penetrate the second article to be mounted. The projecting part of these studs is formed into riveting heads with a specially shaped horn tip. The cavity in the horn is big enough to hold the displaced material and form it nicely. The amplitude of the horn has to be adjusted formaximum motional interence between the plastic part and the horn tip and plastic stud. Heat is then produced by friction between the plastic part and the horn tip, which allows an immediate melting in this area. The pressure controlled by the welding machine lets the riveting head solidify after a short hold time. Multi-tip horns are often used for simultaneous of different areas on the same part.

C. Spot Welding 

Ultrasonic spot welding is used whenever large plastic parts cannot be placed on a traditional machine. Therefore, the welding head designed as a handgun is brought to the part; either manually or with a robot. The advantage of ultrasonic spot welding is the fact that the parts do not need any special preparation(no energy director required). Therefore large size vacuum formed parts ca also be assembled easily.

The ultrasonic horn is built to product high amplitude. The tip of the horn is shaped in order to penetrate high amplitude the two layers of material, leaving a typical ring pattern of the workface, while the backside rests smooth and clean.

D. Embedding

A metal piece such as a threaded insert or bolt has to be embedded into an existing hole in a plastic part. The metal piece is contacted by the oscillating horn, which creates friction between the two part smelting the plastic material. The machine pressure displacews the new melted material into the structure on the metal part surface. Once the displaced material has solidified the inserted piece remains tightly seated and resists to tensional as well as torsion force.

Features:

Pll Auto Tuning

The Pll Auto Tuning technology synchronize the frequency change of horn and the AMP output. The synchronization expand the auto tuning range, simplify the fabrication of the welding horn. The AMP would output the perfect vibration no matter how the temperature rises of the welding horn. Hat would also be able to reduce the welding failure rate. Auto tuning range: 15Khz to 350Hz, 20Khz to 700Hz., 40Khz to 800Hz.

Voltage Feed back

Keep the steady output of voltage and amplitude without AVR system. Input voltage variation is allowed between 180V to 240V. This feedback control could guarantee the welding stability.

Overload protect

The upper and lower specification limits of electric current and voltage can be measured, and th e output can be cut out in case there is problem.

Soft start protect

Effective soft start protect could remove the harm to the horn at the very beginning of vibration, and eliminate the malfunction at the ultrasonic vibration. (Tunable range: 10mses~200mses)

Multi-welder cylinder synchronization

Air pressure inspection and air cylinder moving speed adjustment, these two function could guarantee the synchronization of the cylinders movement when multiple welders in needed.