| 摘要 |
Air bars 12 extending lengthwise parallel to one another are mounted on the front of a plenum chamber 10 with their front walls 28 lying substantially on an arc around which a moving web W is guided. Each air bar 12 has a pair of elongate Coanda nozzle outlets 29, extending along the opposite longitudinal edges of its front wall 28, through which pressurised air from the plenum chamber 10 emerges as streams that converge across the front wall 28 and which support the web W without contact between the web W and the front wall 28. Plates 44 extend between the pairs of adjacent air bars and these plates 44 have their front surfaces on an arc concentric with the arc of the front walls 28 but of smaller radius. An air dam 117 at each end of each plate 44 restricts the flow of air from beneath the web W in the lengthwise direction of the plate 44. Further air dams 45, adjacent each edge of the web W, prevent excessive spillout of pressurised air from beneath the web W. <IMAGE> |
