Ultrasonic Cleaning 101
What are Ultrasonic Waves?
Ultrasonic cleaner waves are sound waves transmitted above 20,000 Hz (20 kHz or 20,000 cycles per second), or higher than the frequency detectable by humans.
Sound waves are created by the vibration of an object, which causes the air molecules around it to vibrate.
These vibrations cause our eardrums to vibrate, which the brain then interprets as sound. When the original vibration is very fast, so are the sound waves, and the pitch of the sound created is too high for the human ear to hear.
In the natural world, animals like dolphins and bats use these ultrasonic waves to communicate, but humans have discovered practical applications. The most commonly known is medical ultrasonography, although in the last 30 years some organizations have discovered highly effective, chemical-free cleaning applications and technology.
Ultrasonic cleaners work in a very similar way to a loud speaker, except the ultrasonic cleaner waves travel at a much higher frequency and through water instead of air. A high-frequency electronic generator that creates ultrasonic waves is connected to a diaphragm, a flat or cone-shaped structure similar to the visible cone-shaped portion of a loudspeaker.
The generator vibrates the diaphragm at a specific high frequency, usually between 25 and 170 kHz, inside a specially designed water tank. The ultrasonic cleaner waves created cause the water molecules to vibrate rapidly, creating alternating waves of compression and expansion within the water. During the expansion phase, or rarefaction cycle, the liquid is torn apart, creating cavitation bubbles. These bubbles are where ultrasonic cleaning technology is born.