Article Contents

1. Introduction
2. FM: Sweep and Dual Sweep
3. Ultrasonic Power Into a Tank
4. FM: Upsweep
5. Multiple Frequencies (1)
6. Multiple Frequencies (2)
7. Cavitation
8. Transducer Impedence (1)
9. Transducer Impedence (2)
10. Transducer Impedence (3)
11. Universal Transducer
12. Applying the Technology (1)
13. Applying the Technology (2)
14. Applying the Technology (3)
15. Conclusion

Designer Waveforms: Ultrasonic Technologies to Improve Cleaning and Eliminate Damage
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The mechanism for producing the energy input responsible for exciting the part into resonance will be more thoroughly explained in this article when the topic of transducer impedance curves is covered; however, here is a brief description. When a typical Langevin type transducer is swept through a bandwidth of frequencies, the output power is not constant for each frequency. Generally, the output power of the generator peaks near the center of the bandwidth. When sweeping up in frequency, a peak pulse of power is put into the tank at the center of the sweep range. When sweeping down in frequency, another peak pulse of power is put into the tank at the center of this sweep range. This process continues producing equally spaced power pulses at a rate equal to two times the sweep rate. See figures 3 and 4 that show a conventional sweep rate graph and a graph of power into the liquid, each on the same time scale.

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