Method and apparatus for shrinking a travelling web of fibrous material
AssigneeJ. M. Voith GmbH
InventorChristian Schiel
Life of this patent
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Abstract
Method and apparatus for shrinking a travelling web of fibrous material by transferring the web of fibrous material on a porous carrier web to a transfer web travelling at a lower velocity than the carrier web, curving the carrier web to a convex curvature toward the transfer web, at the transfer area, and employing a differential pressure to aid in the transfer of the web of fibrous material to the transfer web. Transversal shrinking is also accomplished by deviating the travel direction of the transfer web in the transfer area laterally at an acute angle from the travel direction of the carrier web. The fibrous material may also be transferred to a second transfer web which may also be at a lateral angle to effect transversal shrinking.
Claims10
Method of shrinking a travelling web of fibrous material which comprises moving said web of fibrous material disposed on a porous carrier web to an area adjacent a moving transfer web for transfer of said web of fibrous material to said transfer web, maintaining the velocity of said moving transfer web lower than the velocity of said moving porous carrier, maintaining said porous carrier in a convex curvature toward the transfer web in the transfer area, and maintaining a pressure differential between the pressure at the underside of said porous carrier and the topside of said web of fibrous material by gas under pressure in the transfer area acting on the web of fibrous material, said gas under pressure emanating from a fixed position on the side of the carrier web opposite the side carrying the web of fibrous material, to aid in the transfer of said web of fibrous material to said transfer web.
Apparatus for shrinking a travelling web of fibrous material comprising a porous carrier web for conducting a web of fibrous material, a transfer web for receiving said web of fibrous material, means for driving said porous carrier web to a transfer area adjacent said transfer web for transfer of said web of fibrous material, means for driving said transfer web at a velocity lower than the velocity of said porous carrier web, support means for said porous carrier web in said transfer area to effect a convex curvature toward the transfer web of said porous carrier web and a blasting device through which gas under pressure is applied, fixedly positioned on the side of the carrier web opposite the side carrying the web of fibrous material, for maintaining a pressure differential between the pressure at the underside of said porous carrier and the topside of said web of fibrous material to aid in the transfer of said web of fibrous material to said transfer web.
Dependencies are inferred from the claim text.