Analysis of the influence of ultrasonic transducer on ultrasonic welding
Ultrasonic welding specifications, especially the amplitude of the ultrasonic vibration and the frequency of the output current, have a great influence on the stability of the joint quality. It has the characteristics of a thermal cycle welding, and the stability of the amplitude is low. This kind of welding is produced when the ultrasonic vibration power is not large.
Because, in order to obtain the amplitude that can guarantee the welding quality, we must weld under the conditions close to resonance. Of course, in this case, even if the natural frequency of the mechanical vibration system does not change much, the amplitude will be significantly reduced.
With the increase of the power of the ultrasonic transducer, the change of the amplitude in the ultrasonic welding process will be correspondingly less, so the strength of the joint will have greater stability. This situation can be explained by two reasons:
1. The impact of load changes on high-power ultrasonic transducers is relatively small;
2. Because the connecting joints at a certain contact point are continuously damaged, the mass of the object connected to the vibration transmission rod is relatively small. Therefore, the power of the ultrasonic transducer can be increased to improve the stability of the joint quality.
When there is a generator that can automatically adjust the current frequency according to the natural frequency of the vibration system, the working stability will be completely different. Under the working conditions of the stabilizer, the amplitude is very stable and reaches the maximum value of the transducer, which improves the stability of the joint quality. When we adjust the generator to the same power, we can weld thicker weldments.
