Arrangement in Connection with Curtain Coating of a Fibrous Web

摘要

An arrangement in a curtain coater for starting and stopping coating of a web, having a reservoir and a connected surface extending over the web toward the curtain to collect the coating as the coater moves over the web to start coating the web. A cover plate that swing around a cross-direction shaft connected to the cover plate. In one embodiment the shaft also moves in the machine direction. The cover plate is used to protect an leading edge of the collecting surface from being covered with coating and pivots to be cleaned with fluid which may be supply from the shaft. The cover plate is arranged so the fluid drain off the cover plate onto the collecting surface or reservoir. When clean, the cover plate is repositioned to protect an leading edge of the collecting surface during the next start or stop operation of coating the web.

主权项

1. A curtain coater, comprising:
a movable nozzle beam forming a coating material curtain for coating a fibrous web; a return reservoir having a collecting surface connected thereto, the collecting surface extending to a tip in a direction which extends over the web toward the nozzle beam when the nozzle beam is positioned for coating the fibrous web, the collecting surface arranged to collect the coating material at least before or after the coating of the fibrous web; a mechanism for moving the nozzle beam from a position over the return reservoir and the collecting surface to a position over the web for coating the web; at least one support member for guiding the fibrous web below the coating material curtain when the nozzle beam is in the position over the web; a cover plate movably mounted to swing around a pivoted shaft connected to the cover plate, the shaft extending in a cross-direction with respect to a direction of travel of the fibrous web;
wherein the cover plate is movable between at least two positions, a front position where the cover plate extends beyond the collecting surface tip and toward the coating material curtain positioned for coating the fibrous web and a cleaning position where the cover plate is located to extend above the collecting surface of the return reservoir such that cleaning liquids applied to the cover plate are conveyed to the return reservoir; and wherein the cover plate is movable between the cleaning position and the front position.