超聲波清洗機是利用超聲波在液體中的社會化作用、加速度作用及直進流作用對液體和污物直接、間接的作用，使污物層被分散、乳化、剝離而達到清洗目的。目前所用的超聲波清洗機中，空化作用和直進流作用應用得更多。

Ultrasonic cleaning machine is the use of ultrasonic socialization in the liquid, acceleration and straight into the role of liquid and dirt direct and indirect role, so that the dirt layer is dispersed, emulsified, stripped to achieve the purpose of cleaning. At present, cavitation and direct inflow are widely used in ultrasonic cleaning machines.

（1）空化作用：空化作用就是超聲波以每秒兩萬次以上的壓縮力和減壓力交互性的高頻變換方式向液體進行透射。在減壓力作用時，液體中產生真空核群泡的現象，在壓縮力作用時，真空核群泡受壓力壓碎時產生強大的沖擊力，由此剝離被清洗物表面的污垢，從而達到精密洗凈目的。

(1) Cavitation: cavitation is the transmission of ultrasonic wave to the liquid by the high frequency transformation of the interaction of compression force and pressure reduction more than 20000 times per second. When the pressure is reduced, the vacuum core group bubbles will appear in the liquid. When the pressure is applied, the vacuum core group bubbles will have a strong impact when they are crushed by the pressure, so as to peel off the dirt on the surface of the object to be cleaned, so as to achieve the purpose of precise cleaning.

在超聲波清洗過程中，肉眼能看見的泡并不是真空核群泡，而是空氣氣泡，它對空化作用產生抑制作用降低清洗效率。只有液體中的空氣氣泡被完全脫走，空化作用的真空核群泡才能達到佳效果。

In the process of ultrasonic cleaning, the bubbles visible to the naked eye are not vacuum nuclear group bubbles, but air bubbles, which inhibit cavitation and reduce cleaning efficiency. Only when the air bubbles in the liquid are completely removed, the cavitation effect of vacuum core group bubbles can achieve the best effect.

（2）直進流作用：超聲波在液體中沿聲的傳播方向產生流動的現象稱為直進流。聲波強度在0.5W/cm2時，肉眼能看到直進流，垂直于振動面產生流動，流速約為10cm/s。通過此直進流使被清洗物表面的微油污垢被攪拌，污垢表面的清洗液也產生對流，溶解污物的溶解液與新液混合，使溶解速度加快，對污物的搬運起著很大的作用。

(2) Straight inflow: the phenomenon that ultrasonic wave flows along the sound propagation direction in liquid is called straight inflow. When the intensity of acoustic wave is 0.5w/cm2, the straight flow can be seen by naked eye, and the flow is perpendicular to the vibrating surface, and the flow velocity is about 10cm / s. Through this straight forward flow, the micro oil dirt on the surface of the object to be cleaned is stirred, and the cleaning liquid on the dirt surface also has convection. The dissolving liquid dissolving the dirt is mixed with the new liquid, so that the dissolving speed is accelerated, which plays a great role in the transportation of the dirt.

（3）加速度：液體粒子推動產生的加速度。對于頻率較高的超聲波清洗機，空化作用就很不顯著了，這時的清洗主要靠液體粒子超聲作用下的加速度撞擊粒子對污物進行超精密清洗。

(3) Acceleration: the acceleration of liquid particles. For the ultrasonic cleaning machine with higher frequency, the cavitation effect is not significant. At this time, the cleaning mainly relies on the acceleration of liquid particles under the ultrasonic effect to impact particles to clean the dirt.