Sheet drying apparatus

Claim 1

Apparatus for drying sheet-like materials, comprising a hollow drying chamber having an inlet end and a discharge end, the cross-sectional area of said inlet end being substantially smaller than the cross-sectional area of said discharge end; first rotary sheet advancing means comprising a pair of rolls closely adjacent to said inlet end; second rotary sheet advancing means adjacent to said discharge end and defining with said first sheet advancing means an elongated path for travel of sheet-like material into, through and beyond said chambeR; a source of gaseous drying fluid; and first and second nozzle means provided on said chamber adjacent to said inlet end at the opposite sides of said path and connected with said source, said nozzle means having orifices closely adjacent to said path and arranged to discharge streams of gaseous drying fluid against the respective sides of sheet-like material in said chamber whereby the drying fluid flows along the sheetlike material to leave said chamber by way of said discharge end, the cross-sectional area of said discharge end being large enough to allow for substantially unobstructed escape of gaseous fluid which is admitted into said chamber by said nozzle means and the cross-sectional area of said chamber decreasing in a direction from said orifices toward said discharge end to a point near the discharge end and then increasing in cross-sectional area to the discharge end, said second sheet advancing means comprising first and second roll means located at opposite sides of said path, said first and second roll means defining a plurality of large passages so as to offer little resistance to escape of gaseous drying fluid by way of said discharge end.