In recent years, it is required for substrate handling such as glass plate of FPD, silicon plate of solar cell to develop the non-contact transportation technology. In this study, ultrasonic flexure vibration stator is set above the substrate which is levitated by aerostatic table. It is assumed that three components of forces act on transported substrate; squeeze force, viscosity force generated by stator and aerostatic force. Because the squeeze force inclines the substrate, the horizontal component of aerostatic force is to be drag force. The time-varying distribution of air film pressure is investigated numerically by compressed Reynolds equation. The results of numerical analysis of attitude and position of substrate were compared with measured value to verify the proposed theory. The offset weight to incline the levitating substrate was approximately proportional to horizontal force. The measured results of film thickness, inclination of substrate and drag force by relative position of stator agreed approximately with numerical results.
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