結合氣壓軸承之非接觸式氣壓真空吸盤設計

An Absolute Non-Contact Vacuum Pad with Embedded Air Bearings

本文主要探討的是如何利用流場分析模擬軟體 （CFD），來模擬設計出一具有氣旋式原理的新型非接觸式真空吸盤，並為了保證真空吸盤與吸附物件之間是以非接觸式且達到絕無碰撞的情形發生，本文將引用氣靜壓軸承之小孔節流器設計原理來防止兩者物體間吸附時瞬間被碰撞，其中，絕無碰撞非接觸式真空吸盤設計是利用4個對稱氣壓軸承與非接觸式真空吸盤結合，來設計出絕無碰撞非接觸式真空吸盤，此外，利用閉迴路控制技巧來操作出一款具備間距感知及控制 （gap sensing and control） 的非接觸式真空吸附裝置，也成功避免了真空吸盤與吸附物件之間可能產生瞬間碰撞的問題，其最主要的原理為，由於非接觸式真空吸盤是採用輸入氣體方式使內部產生旋轉氣場，進而產生真空吸力來吸取物件，而旋轉氣場由吸盤底部快速噴出，產生氣墊層，與物件保持一定距離，形成非接觸式之吸附，為了避免真空吸盤與物件之間發生瞬間碰撞，則利用4個氣壓軸承瞬間噴出氣體以相反的力量來抵制，以達到絕無碰撞的情形發生。在本文中，利用5口3位氣壓式比例方向閥來進行切換控制。未來，本真空吸盤技術應可用於晶圓、TFT面板或太陽能板等吸附及搬運領域中。

In this paper, a novel vacuum pad based on CFD simulation and vortexlevitation principle is proposed. To ensure absolute non-contact betweenthe vacuum pad and the work-piece, four symmetrical air bearings are introducedand integrated into the design of the vacuum pad. In addition,the closed-loop gap control is applied to the operation of the vacuum pad,which avoids successfully the possible initial collision and maintains thedesired gap between the vacuum pad and the work-piece. The vortex in- side the vacuum pad serves to levitate the work-piece while the air bearings,on the contrary, try to push the work-piece away if the work-piece comestoo close to the vacuum pad. Therefore, proper function switching betweenthe vortex and the air bearings is necessary. In this paper, a 5/3pneumatic proportional directional control valve is utilized to switch thefunctions mentioned above. In the future, such a vacuum pad may findsome potential application, like pick-up and transportation devices forTFT-LCD, solar energy panels, etc.