◆　Principles of ultrasonic washing

High frequency surging signals, sent out by ultrasonic generator, change into high frequency machinery shakes through the transducer and spread into the medium, washing solvent. The ultrasonic radiate forward with alternate density in the washing solvent, make the liquid flow and produce tens thousands of small bubbles. These bubbles form and grow in the negative pressure area of the ultrasonic vertical traveling, then close rapidly in the positive pressure area. In course of such so-called "cavitations ", bubble closing can form a twinkling high pressure over 1000 air pressure. The twinkling high pressure, which is constantly producing, strike the material surface like to a succession of "exploding", and make the dirt of surface and chink peel off rapidly, so that achieve the purpose of purifying the material surface.
Right chart is a section of transducer working in water: (Picture: Tech1),
There is a flat of certain thickness stainless steel in the middle, with the transducer stuck under it, the ultrasonic generator produce the alternating current signal with certain frequency and voltage, and it drive the steel flat and the transducer shake high frequently, when the steel flat is shakes upwards, it pushes water upwards, and as the steel flat shakes downwards, water can not catch up with the speed of vibrations of the steel flat, this forms a piece of space between water and steel flat, so, shaking repeatedly will make a lot of bubbles shape, as to the drawing: The bubbles are produced by "cavitations“, we call them cavitation bubbles. The cavitation bubbles spread into the water in the direction of the shaking, if there are work pieces in the water, the cavitation bubbles will bump against their surfaces, and produce the bump force of several thousands atmosphere pressure, so drive the dirt on the work piece surface fall off.