Abstract A barrier coating of the high viscosity ''''hot melt'''' class is applied with high uniformity to a moving web by means of a coating apparatus which is capable of operating at speeds as high as 1,500 feet per minute utilizing ''''hot melt'''' compounds of viscosities ranging as high as 100,000 c.p.s. The coating fluid in a heated condition is applied from a coating head consisting of a tubular body formed with an elongated aperture over which the web is passed. The coating fluid is under relatively high pressures of varying intensity. Pressure change along the elongated aperture is controlled by regulating web pressure. Multiple tensioning means are arranged at two opposite sides of the coating tube. One tensioning device engages the web at it approaches the coating head and acts initially to exert cross tension and stretch the web sufficiently to overcome variations in caliper and web length. A second tensioning device exerts linear tension to force the transversely stretched web uniformly against the coating tube with sufficient web pressure to equalize and balance pumping pressure of fluid all along the coating aperture. Required web pressures of a magnitude necessitating linear tension in excess of the tensile strength of any given web is provided by means of a web press roll adjustably supported in rolling contact with the web immediately above the elongated tube aperture. The web press roll is adjustable both vertically and horizontally to vary its position relative to the elongated tube aperture.
Inventors
👤 G Park
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-10-28 19:33
CPC Classifications
D; D06; D06B; D06B1/00; D06B1/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
243 words
Apparatus for applying a viscous coating of the hot melt class to a web of material, said apparatus comprising a frame, a supply roll member for supporting a wound roll of the material at one end of the frame, winding roll means mounted at an opposite end of the frame, power driving mechanism for actuating the winding roll and drawing off a web of the material at a desired rate of travel, a coating tube arranged in the frame below the path of said web to engage the web, said coating tube being constructed with a curved upper side and having an elongated discharge aperture formed along said upper side and lying within the confines thereof, said aperture having high lead-on edge and a low lead-off edge, tension roll means located both in advance of, and in rear of, said tube on said path for exerting tension in the web and guiding the web in an arcuate path of travel over said curved upper side and over said lead on and lead-off edges, a roll mount structure, a press roll rotatably supported in the roll mount structure above the coating tube in rolling engagement with the web and forming a pressure nip with said tube, and said press roll having its axis of roTation in rear of said lead on edge directly above said lead-off edge and lying in a vertical plane which passes through the lead-off edge of the elongated discharge aperture.
Claim 2
Dependent Claim
243 words
Apparatus for applying a viscous coating of the hot melt class to a web of material, said apparatus comprising a frame, a supply roll member for supporting a wound roll of the material at one end of the frame, winding roll means mounted at an opposite end of the frame, power driving mechanism for actuating the winding roll and drawing off a web of the material at a desired rate of travel, a coating tube arranged in the frame below the path of said web to engage the web, said coating tube being constructed with a curved upper side and having an elongated discharge aperture formed along said upper side and lying within the confines thereof, said aperture having high lead-on edge and a low lead-off edge, tension roll means located both in advance of, and in rear of, said tube on said path for exerting tension in the web and guiding the web in an arcuate path of travel over said curved upper side and over said lead on and lead-off edges, a roll mount structure, a press roll rotatably supported in the roll mount structure above the coating tube in rolling engagement with the web and forming a pressure nip with said tube, and said press roll having its axis of roTation in rear of said lead on edge directly above said lead-off edge and lying in a vertical plane which passes through the lead-off edge of the elongated discharge aperture.