Web controlling apparatus
AssigneeAgfa-Gevaert
InventorsJoseph I. De Roeck, Eric J. Blondeel, Lucien A. Christiaen
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Abstract
An apparatus for controlling an outgoing web leaving an air cushion turning bar, which enables a convenient transport of longitudinally curved webs over such air turning bar. The apparatus comprises at least one axially displaceable roller adapted to be moved laterally upon a deviation in the web to bring the same to its outgoing path, and a second roller capable of bodily tilting movement and preferably axial movement as well, to differentially lengthen the path of the web edge margin remote from the direction of deviation.
Claims10
Apparatus for correcting the path of a travelling web including an imperfect curved web as it leaves an air cushion turning bar, characterized in that such apparatus comprises:
- a freely rotatable roller, means supporting said roller for bodily axial displacement along a fixed axis, said roller being arranged on said web path as the first contact for a web leaving the turning bar, a second freely rotatable roller downstream of said first and defining between them a stretch of the path which makes an angle with the upstream adjacent portion of said path and is generally perpendicular to the adjacent portion of said path downstream of said second roller, means mounting said second roller for pivotal movement about an axis generally perpendicular to said adjacent portion of said path downstream of said second roller, means for detecting a lateral deviation by said web from its correct path, and operating means actuated in response to said detecting means for effecting axial bodily displacement of said first roller in a direction opposite to said deviation and for substantially simultaneously tilting said second roller about said axis to differentially lengthen the path of the edge margin on the side of the web opposite the direction of deviation.
Dependencies are inferred from the claim text.