High velocity web floating air bar having air flow straightening means for air discharge slot means

DETAILED DESCRIPTION The present invention provides an elongated and generally tubular air bar which is adapted to be positioned closely adjacent to a running web for supporting the web on a cushion of pressurized air.
The air bar includes transversely positioned air discharge slot means across the web to which pressurized air is fed from a central chamber of the air bar and through separate air delivering passageways in the air bar.
Air flow straightening means are located in the passageways and are positioned transversely therein with respect to the elongated air bar whereby pressurized air which is directed into the central chamber of the air bar then enters the passageways and the air flow is straightened and guided by the straightening means so as to assume a normal direction of flow to the air discharge slot means.
Thus the air which is introduced into the air bar is caused to pass the straightening means before it is discharged through the slots and thereby the cross machine momentum components of air movement are dissipated which results in the discharge of air through the slot means at right angles to the web in a transverse direction of the web.
One aspect of the invention provides an air bar of the above type in which the air straightening means are formed as flutes pressed into an inner wall and which flutes extend closely adjacent the lip or nozzle edge of the air slots to rigidify the latter and support it in its proper position to thereby insure a uniform gap for the air discharge slot.
Another aspect of the invention relates to the air straightening means being formed as a series of elongated strips welded or otherwise secured to an inner wall of the air bar.
These and other objects and advantages of the present invention will appear hereinafter as this disclosure progresses, reference being had to the accompanying drawings.