variable frequency ultrasonic generator circuit diagram

The principle of the generator is that the signal generator first produces a specific frequency signal, which can be a sinusoidal signal or a pulse signal. This specific frequency is the frequency of the transducer. Usually used in ultrasonic equipment, the ultrasonic frequency is 20KHz, 25KHz, 28KHz, 33KHz, 40KHz, 60KHz. Z or above is not yet widely used. But with the continuous development of precision cleaning in the future. I believe the use will gradually expand.

 

A more perfect ultrasonic generator should also have a feedback link, mainly to provide two aspects of the feedback signal: one is to provide output power signal, we know when the generator power supply (voltage) changes. The output power of the generator will also change, which is reflected in the transducer is the mechanical vibration of the big or small, resulting in unstable cleaning effect. Therefore, it is necessary to stabilize the output power and adjust the power amplifier by power feedback signal to make the power amplification stable. The second is to provide frequency tracking signals. When the transducer works at the resonant frequency point, its efficiency is high and its work is stable. But the resonant frequency point of the transducer will change because of assembly reasons and working aging. Of course, the frequency of this change is only drift, the change is not very big. The frequency tracking signal can control the generator, so that the frequency of the signal generator in a certain range. The resonant frequency of the transducer is tracked. Let the generator work in excellent condition. Of course, with the development of modern electronic ultrasonic technology, especially microprocessor (uP) and signal processor (DSP), the generator is becoming more and more powerful, but no matter how it changes, its core function should be as mentioned above, but the ultrasonic technology is different in each part.