Surface acoustic wave atomizer with pumping effect

Abstract

We propose a surface acoustic wave device for miniaturization of ultrasonic atomizers and for functional system construction. Actually, ultrasonic atomizers are rather smaller than other method, so that nebulizers which are handy to carry type use ultrasonic vibration. But they are to large for a pocket or an endoscope. We have obtained a fine mist with a first trial of surface acoustic wave atomizing device whose dimensions are pocketable size. This functional device is able to reduce the dimensions to mm-order as a system. The atomizer consists of a vibrator, a cover and a tube. The vibrator and cover material is 127.8" Y-cut LiNbO, to generate Rayleigh wave, a kind of surface acoustic wave. The Rayleigh wave is the driving force of pumping effect and atomizing effect. The pumping effect is caused by the wave motion of the elastic material and viscosity of the fluid like an ultrasonic motor. The atomizing rate varied according to the driving voltage. The maximum rate was about 0.1 ml per minute. The mean diameter was 19 ym.