Ultrasonic welding is a technique that generates vibration through high frequency sound waves. The vibrations are transferred to the subject to be joined under pressure, this occurs in a specified area, thus welding the subject together. The primary application is seen in plastic. One of the advantages of ultrasonic welding is that no bolts, solder or glue should be used to collect the item.
Ultrasonic welding is a good alternative to other assembly methods such as screws, click assemblies, and glue, as a very consistent quality is achieved in the assembly.
How does it work?
The joining of injection molded thermoplastic subjects is done by means of a welding horn adapted to the geometry of the subject. The welding horn is connected to a transducer that transforms the electrical energy into physical vibration.
The subject is placed on a fixture, the fixture supports the subject on the areas to be welded, after which the welding horn is pressed down over the subject and the welding is carried out.
By ultrasonic welding of plastic, the interface of the two subjects to be collected is typically designed to concentrate the melting process. One party will typically have a shape where a tip acts as an energy conductor to start the melting process.
The energy from the ultrasound melts the plastic into the contact surfaces between the two subjects and creates a perfect collection.