US 4,766,840 A · Paper coating machine

Abstract

A highly compact machine for applying an attractive protective coating to a paper web that passes through a printing press is located between the last press stand and the dryer of the printing press, and to enable the machine to receive the web, the printing press is provided with an apparatus for directing the web back to the print stands and the machine after the web passes through the dryer. The machine includes upper and lower blanket cylinders, a plate cylinder contacting the lower blanket cylinder, and an oscillating cylinder below the plate cylinder. In addition the coating machine includes a pan containing a coating fluid and a pan roller, the surface of which rotates through the fluid in the pan to lift it out of the pan. A metering roller revolves close to the pan roller to remove excess fluid from the pan roller which thereupon transfers the fluid to a form roller. That form roller runs against the oscillating cylinder and transfers the fluid to the oscillating cylinder. Another form roller contacts both the oscillating cylinder and the plate cylinder, and transfers the fluid to the plate cylinder. The plate cylinder delivers the fluid to the lower blanket cylinder which in turn applies it to the web. The plate cylinder carries a cylindrical plate which is normally continuous, but may be left with a cutout or void so that a small portion of the web is left uncoated with each revolution of the blanket cylinder.

Claims24

Dependent claims

In combination with a printing press including at least one print stand where a printed image is applied to a web and a dryer located beyond the last print stand and including a first drying chamber through which the web passes to dry ink that is applied to it at the print stands, the improvement comprising:

deflecting means for directing the web back toward the last print stand after the web passes through the dryer, and a coating unit physically interposed between the last print stand and the dryer, said coating unit comprising:
first and second blanket cylinders which are located adjacent to each other so as to form a nip between them, with the nip being located such that the web passes into it after passing through the dryer and being directed back toward the last print stand by the deflecting means, a plate cylinder located adjacent to the second blanket cylinder and carrying a generally cylindrical plate which bears against the surface of the second blanket cylinder, and transfer means for applying a coating fluid to the outwardly exposed surface of the plate, whereby the coating fluid is transferred to the second blanket cylinder and thence to the web as the web passes through the nip.

In combination with a succession of print stands through which a web of paper passes to have inked images applied to the web and a dryer through which the web also passes to dry the ink on the paper of the web, with the dryer being located beyond the last print stand, the improvement comprising:

means for directing the web of paper back toward the last print stand after it passes through the dryer, and a machine located between the last print stand and the dryer for receiving the web and applying a coating fluid to the web after the web is directed back beyond the dryer so as to provide the paper with a protective coating, said machine comprising:
a frame;
upper and lower blanket cylinders mounted on the frame such that a nip exists between them for accepting the web;
a plate cylinder mounted on the frame generally below the lower blanket cylinder and having a cylindrical plate that contacts the lower blanket cylinder;
an oscillating cylinder mounted on the frame generally below and spaced from the plate cylinder and oscillating to and fro along its axis as it rotates;
drive means for rotating the blanket, plate and oscillating cylinders such that they all have the same surface velocity;
a pan for holding the coating fluid;
a pan roller that rotates within the pan so that the coating fluid wets its surface;
a first form roller mounted on the frame and being normally in contact with the cylindrical plate of the plate cylinder and the oscillating cylinder for transferring coating fluid from the oscillating cylinder to the cylindrical plate;
and a second form roller mounted on the frame to normally rotate in close proximity to the pan roller and generally in contact with the oscillating cylinder for transferring coating fluid from the pan roller to the oscillating cylinder.

7 more elements

Dependencies are inferred from the claim text.

Paper coating machine

Life of this patent

Paper coating machine

Life of this patent

Abstract

Claims24