Research On Vibration Characteristics Of Glass Substrate Supported By Air Floating

Air floating non-contact transport is widely used in glass substrate defect detection instruments because of its non-contact,pollution-free and non-magnetic characteristics.Due to the non-uniform pressure distribution of air film and unstable thickness of air film,the glass substrate will generate corresponding deformation or vibration under air-floating support,which will affect the accuracy of defect detection.In order to solve this problem,this paper combines theory with experiment to study the vibration of glass substrate supported by air floating.The main work and conclusions are as follows:(1)Based on the basic theory of gas lubrication and the simulation diagram of air film pressure distribution,the air pressure distribution of air film is deduced in the form of airbearing unit,and the relationship between the air film bearing capacity and the air film thickness is further established.;(2)Aiming at the low frequency vibration of glass substrates supported by air floating,based on the change of gas compression in the air chamber of air-floating support,the mechanism of low frequency vibration is explored,and its mathematical model is established.According to the established low frequency vibration model,the main air floatation parameters affecting the low frequency vibration are analyzed and obtained.Low-frequency vibration experiments of glass substrate were carried out by adjusting the air-float parameters.The experimental results verify the accuracy of the mathematical model;(3)Aiming at the high frequency vibration of glass substrate supported by air floating,the software simulation shows that the main cause of high frequency vibration of glass substrate is the vertical component air flow at the positive pressure hole.High-frequency vibration experiments of glass substrate were carried out by adjusting the air-float parameters,and the correctness of the analysis was verified by experiments.The influence laws of different air-float parameters on high-frequency vibration were summarized through experiments.By means of orthogonal design experiments,the influence of various air-float parameters on the amplitude of high-frequency vibration of glass substrate is compared and an optimum set of air-float parameters is obtained.