SM1000 Sonic Meter Ultrasonic Cavitation Meter

The Sonic Meter SM1000 Ultrasonic Cavitation Meter quantifies the ultrasonic pressure output of a liquid filled ultrasonic cleaning tank. If a tank's ultrasonic output is diminished, the quality of the parts and the processes that follow the production may drift from the original specification. The Sonic Meter is designed to help maintain process stability of ultrasonic cleaners by quantifying the tanks output during scheduled calibration intervals.

Ultrasonic cleaners utilize a transducer attached to the tank's exterior. The transducer outputs pulsating mechanical energy at high frequencies (ultrasonic), which cause the liquid in the tank to agitate.

The agitation at this high frequency level is what gives ultrasonic cleaners their cleaning ability. As the liquid becomes agitated, a phenomenon known as cavitation takes place. Cavitation is the almost instantaneous formation and implosion of small bubbles and cavities in the cleaning liquid.

As the liquid cavitates, the minute bubbles and the coincident implosions cause the surrounding liquid to impinge forcefully upon the surface areas of the part being cleaned. The force that the liquid applies to the area of the part is commonly referred to as the scrub-force.

This scrub-force action takes place throughout the tank. However, the scrub-force can vary significantly due to the placement of the tank's transducer and the constructive and destructive interference caused by the shape of the tank and parts being cleaned.

These process variations in scrub-force throughout the tank can be referred to as hot or cold spots in the liquid. Hot and cold spots are locations of high and low intensity scrubforce relative to a mean value scrub-force. These process variations can significantly alter the cleanliness or integrity of the parts being cleaned. Some parts may not have been thoroughly cleaned for the next process, or the stresses due to the cleaning action may have altered the integrity of the parts. With the Sonic Meter these process variation can be minimized.

With the Sonic Meter's slender probe, operators can probe ultrasonic cleaners to pinpoint areas of optimum intensity in which to place each part. The Sonic Meter's displays the intensity variations. Parts could be varied in their z-height or their x and y positions via an adjustable array fixture. The operator can determine the location for each part so that all parts are placed in regions of the same specified pressure range (scrub-force). Or several readings could be taken and averaged to determine the mean value scrub-force of a particular cleaner.

The Sonic Meter SM1000 measures scrub-force in units of pounds per square inch (psi). The SM1000 works with tanks that use frequencies in the range of 0-500kHz.