Design and manufacture of stainless steel/carbon epoxy hybrid shaft for cleaning large LCD glass panels

Long brush shafts are used to clean large glass panels of liquid crystal display (LCD). Since the surface quality of glass panels is most important for LCD products, reliable cleaning of the glass panels is indispensable during the manufacturing process of LCD product. Generally, stainless steel tubes covered with outside soft brush have been used for cleaning LCD glass panels. Although the stainless steel tube rotates at the low rotating speed of 700 rpm, support bearings fail frequently earlier than the design period due to whirling vibration and shaft tilting.In this work, a hybrid composite shaft composed of outside stainless steel tube and inside carbon/epoxy composite layer was designed to increase the specific stiffness of the shaft. The composite layers were stacked inside the stainless steel tube to protect the composite material from acid liquid for cleaning, and co-cured using a flexible pressure tube to decrease manufacturing cost. The deflection and tilting angle due to gravity and the fundamental natural frequency of the hybrid shaft were calculated and compared to those from experimental results.