Roller coating Machines

ROLL COATING MACHINE Filed Oct. 8, 1931 ATTORNEY Patented Apr. 17, 1934 PATENT OFFICE ROLL COATING MACHINE Charles A. Dickhaut, Highland Park, N. J., as-

This invention relates to roll coating machines. Various methods and apparatus have been used for the coating of papers, textiles and other mathe roll andin consequence the coating is applied indefinitely resulting in a streaky appearance. Smoothing rolls have been used to iron out the ridges left by the nip or coating roll but have been ineffective as the same ridges form on the smoothing roll and are redeposited by the leaving side of the roll. To overcome the streaking efiect or lining action the smoothing rolls have been positioned at an angle so that 10 the lines will be put back at a different point. The theory being that if a suificient number of lines are put back close enough together a uni- A form coating will be had. In practice, however, it hasbeen found impossible to accomplish the elimination of the streaking effect by the angling of the smoothing rolls. In order to reduce the streaking efiect it is necessary to brush out the lines by oscillating brushes. Under certain conditions the brushes are ineffective to eliminate streaking. In addition, they are a source of expense as they wear relatively quickly and cause excessive shutdowns due to the necessity of the brushes being frequently cleaned. The capacity of such a coating machine is-likew ise limited since the speed of the paper cannot exceed a certain speed. The brush must oscillate with a certain speed with respect to the speed of the paper and as there are mechanical limits on the brush oscillation speeds there are limits upon the speed of the travel of the paper. If the coating machine is operated in connection with a high temperature drier the stoppage of the machine to clean brushes, replace same or for any other purpose destroys the sheet of paper in the drier for commercial uses. Also any stoppage increases the labor cost as well as reducing the outlet. In addition to the difliculty in securing uniformity of appearance there is the further difficulty of applying a predetermined thickness of coating or predeterminedly varying the thickness.

One of the objects of this invention is to provide a roll coating machine adapted for coating material on one or both sides.

A further object of this invention is to apply a coating uniformly having a smooth, even appearance without streaking or lining.

A still further object of this invention is to easily control the depth of coating.

Still other objects of the invention are to increase the capacity of the machine by increasing the speed of coating and speed of travel of the material being coated and to reduce shutdowns by reason of brush trouble.

Referring to the drawing:

Figure 1 is a view in side elevation of a machine embodying the principles of my invention.

Figure 2 is a diagrammatic view of the nip or coating rolls and the smoothing rolls and coating removers cooperating therewith and showing the threading of the material around the rolls.