GB474596A - Machine for coating paper or other flexible material in web form - Google Patents

Abstract

474,596. Coating webs such as paper. MASSEY, P. J., and CONSOLIDATED WATER POWER & PAPER CO. Jan. 27,1936, No. 35881/35. Convention date, Sept. 11, 1935. [Classes 96 and 140] [Also in Group XIII] Apparatus for coating a flexible web, e.g. paper comprises a set of contacting distributing rolls having their axes in a horizontal plane for smoothing and working the coating and conveying it towards a coating roll. As shown, a web 4 passes between a pair of rolls 57 and 64 one or both of which is supplied by transfer rolls 55, 56 or 62, 63 with coating material smoothed &c. by distributing rolls 52-54 or 58-61. The coating material is supplied between rolls 20 and 23 or 40 and 41, dams being provided to retain the material in the nip, and the rate of supply to the distributing rolls is controlled by varying the speed of rolls 20, 23, 40 and 41 which are separately driven. In the lower series, the pair of rolls 20 and 23, the distributing rolls 52-54, and the pair of transfer rolls 55 and 56 are mounted on standards pivoted at 16, 67, 76, 80, and 85, the spacing between the rolls being adjustable by screws such as 28 and 105, having oppositely or differentially threaded ends engaging in threaded bushings pivoted on pins on adjacent standards. One bushing of each pair is slotted where it engages the pin so that the rolls may be separated, e.g. when only one side of the paper web is to be coated, by reversing the fluid pressure supply to cylinder 10 by which the rolls are normally pressed together. Rolls 23 and 52 may be separated without separating the other rolls by rotating an eccentric 134 embraced by a forked bushing 132 which is connected to bushing 136 by a screw 139. The distributing, transfer and coating rolls may then be cleaned by discharging water thereon while rotating. Rolls 20, 52, 54 and 57 are driven clockwise, the others counter-clockwise, the distributing rolls being all of different diameters, and the distributing, transfer, and coating rolls being driven at a uniform peripheral speed equal to the speed of the paper web. Rolls 20 and 23 are of metal, and have hard and medium-hard rubber coverings extending short of each end of the roll; a pair of dams is provided at each end of the nip riding on the rubber coverings and on the metal respectively, water being supplied between them for lubrication. The remaining rolls are rubber-covered, but roll 52 may be of non-corrosive metal. An idler roll 73 is positioned above roll 52, and rolls 52 and 53 may be oscillated longitudinally as well as rotated. Roll 56 may be adjusted in position with respect to roll 55. The coating roll 57 is cleaned by a roll 148 having a hard porous surface, e.g. natural or artificial stone, and provided with a scraper 167. The upper series of rolls differs in that a rotatable shelf 124 is provided to receive the end 33 of frame 34 when the upper series is to be retained in the separated or inoperative position, an additional distributing roll 58 is provided, and coating roll 64 is vertically adjustable. To dry the coatings hot air is directed on to the paper from nozzles in conduits 170 and 173, the nozzles near the edges being directed outwardly to place the web under transverse tension. Hot air is also injected on to the outer surface of the web as it passes around guide roll 176 and drying roll 179, and into the nips between the web and these rolls. The machine may form part of a paper-makingmachine, being interposed between banks of drying rolls. Specifications 418,533, 423,512, 463,291, 474,660, 474,828, and 474,829 are referred to.