Patent GB-665891-A (GB)
Title: Single coating machine
Filed: 1948-10-04
Abstract: 665,891. Coating-machines. TIME, Inc. Oct. 4, 1948 [Oct. 6, 1947], No. 25840/48. Class 140. A coating machine for webs of flexible material has a coating unit comprising an applicator roller which is rotatably mounted in a fixed position in a frame of the machine, for applying coating composition to the web, a back-up roller for holding the web against the applicator roller and having means for supporting it for movement toward and away from the applicator roller; a coating fountain; and at least one distributer roller for delivering coating composition therefrom to the applicator roller, the distributer roller, or each of them, being mounted to move under the action of gravity away from the applicator roller, a distributing roller being in contact with the coating fountain; and means for adjusting the coating fountain, and therewith the distributing roller, or rollers, toward . and away from the applicator roller. Two such units may be mounted one above the other in a frame, with means for guiding the web so that first one side and then the other is coated. The machine comprises a base 10 from one end of which extend upwardly a pair of standards 11, 12, and from the other end a pair of standards 14, 15, both pairs being braced transversely. Side plates 17, 18 extend between the standards 12, 15 and together with similar plates 19, 20, extending between the standards 11, 14 support various elements of the machine. An applicator roller 70 is journalled in fixed bearings 69, 69a in the standards 14, 15, and a. coating fountain 23, distributer rollers 71, 72, 73 and a back-up roller 100 are mounted adjustably with respect to this. The coating fountain 23 is slidably supported on horizontal flanges on the side plates 18, 20 and comprises side plates 24, 25 in bearing members on which are journalled the gate rollers 30, 31, the ends of the nip between these being closed by spring-pressed plates 32, 33. The coating composition is delivered to the fountain through upwardly directed holes in a pipe 36. The gap between the rollers 30 and 31 may be adjusted by means of shafts 37, 38, threaded in bosses in the bearings 26, 28 of the roller 30, which are slidably mounted on the side plates 24, 25. The shafts 37, 38 may be rotated by wormgears 39, 40 and worms 41, 42, the latter being mounted on a shaft 43 provided with a hand wheel 45. The shaft 43 is divided, the two halves being connected by a clutch 43a, which may be disengaged to allow adjustment of the alignment of the rollers 30, 31. The entire coating fountain 23 is movable along the rails 21, 22 by means of two worm gear drives each comprising' a threaded shaft 47 fixed to the fountain, and extending through a two-piece gear housing 48 (not shown), 49 sliding on a rail 21 on 22. A worm-gear 56 having internal threads engaging the threads of the shaft 47 is mounted for rotation in the housing 48, 49 and may be rotated by a worm 55. A spring 61 surrounding the shaft 47 presses against the housing 48, 49 and an angle member 62 on the standard 12 and urges a stop 49b on the lower part 49 of the housing into contact with a stop 63 on the side plate 18. The worm 55 is connected to the corresponding worm in the mechanism at the opposite side of the fountain 23 by a divided shaft 65 incorporating a clutch 65a to permit alignment of the two sides; this shaft 65 may be rotated by an electric motor 68 through a belt 67 and pulley 66. A limit switch 285 may be operated through link 281 and bell-crank lever 282 to a lug on the housing 49, and is thrown when either, on the housing 49 approaching the fountain 23, a lug 283 on the latter strikes the arm 284 of the switch 285, or when the adjustable stop members 90, 83, 84 and 85 are brought up against their respective strike members, and the spring 61 is compressed.' The switch 285 is included in an electrical circuit which provides for starting, reversing, stopping and applying a solenoid brake to the motor 68. The coating composition is delivered by the gate roller 31 to 'the first of the series of distributer rollers 71, 72, 73, which may have different surfacing materials, e.g. the roller 72 may be a metal roller and the remaining distributer rollers and the applicator roller 70 may have rubber surfaces. The roller 72 may be hollow and be supplied with a coolant as described in Specification 643,747. The distributer rollers are brought into co-operating relationship with the roller 70 by adjustment of the fountain 23. The journal blocks 76, 77 and 78 of the rollers 71, 72 and 73 are provided with bottom grooves slidably engaging inclined guide surfaces 74, 75 on the side plates 18 and 20, proper spacing of the blocks being secured by adjusting wedges 83, 84, 85 which engage inclined surfaces between the blocks, or in the case of the wedge 85 between the block 78 and a fixed stop 80a on the bracket 80. The positions of the wedges may be adjusted by means of threaded studs. Spacing of the roller 71 from the gate roller 31 is obtained by a slide member 90 carried on each of the end plates 24, 25 of the fountain 23 having a roller 91 engaging a lug 76b on the journal block 76. The rollers 71, 72, 73 are prevented from sliding off the surfaces 74, 75 when the fountain is withdrawn by means of stops 76c, 77b and 78b which then engage stop lugs 92, 93, 94 on the side plates 18, 20, the spacing of the lugs being such that, when they are so engaged, the rollers 71, 72, 73 are separated. Misalignment of the plain straight-bore bearings of the roller 72 during movement thereof is prevented by racks 95, 96 on the journal blocks 77, engaged by gears 97, 98 fixed to a shaft 99. The roller 72 is given an axial reciprocating movement by means of a worm 136 (Fig. 9), on its shaft 131, rotating in a housing 130 and meshing with a gear 137, also journalled therein, on whose shaft links 146 are pivoted with adjustable eccentricity. The other ends of the links 146 are pivoted on a lug 147 on a bearing block 77. The applicator roller 70 co-operates with the back-up roller 100, the shaft 105 of which is journalled eccentrically in a disc 104 (Fig. 6), carried by a collar 103 which is rotatable in the split bearings 101, similar bearings being provided at the other end of the shaft and rotation of the two collars co-ordinated by means of gear segments 107, gears 109 and 111 and a cross-shaft 112. The collars may be rotated to cause the roller 100 to engage the roller 70 by means of a hydraulic or pneumatic jack 116 pivoted at 115 on the standard 15, and having a piston rod 117 pivoted at 118 to a lug 120 on the collar. A stop member 122 on the lug 120 is adapted to engage a rod 121 guided in fixed members and positioned by a nut 125. A second coating mechanism, comprising a fountain 150, distributer rollers 154, 155, applicator roller 156 and back-up roller 158, substantially duplicating the above-described mechanism, is provided for coating the other side of the web W, which is guided around idler rollers 160, 162, 163, 164, over an adjustable supporting or pinch roller 165, between the applicator roller 156 and the back-up roller 158, and finally between the applicator roller 70 and the back-up roller 100. A rope-feed mechanism for gripping the edge of the web and threading it through the machine comprises ropes R<SP>1</SP>, R<SP>2</SP> which pass around pulleys mounted for free rotation on the shafts of the rollers 160, 162, 163, 164, and pulleys 171, 171b on the shafts of the rollers 158 and 100, the rope R<SP>1</SP> returning over pulleys 201, 203, 205, 206, 207, 208 to the pulley 200, and R<SP>2</SP> over pulleys 210, 205, 206, 212, 207, 208 to the pulley 209. A train of gears, driven from the shaft of the roller 158, and a hydraulically or pneumatically-operated clutch mechanism, are provided, whereby the pulley 171 may be driven with the roller 158, so that the ropes advance the paper through the machine, or may be held stationary. The applicator rollers 70 and 156 and the back-up rollers 600 and 158 are driven by means of an electric motor 220, which drives the lower back-up roller 158 through a train of gears 222, 223, 225, 226. The shaft 224, on which gear 225 is mounted, also carries the cone elements of a variable-speed V-belt transmission 228, which drives the applicator roller 156 through gears 243, 244, 245, and a gear 246, which meshes with a gear 247 driving a variable-speed V-belt transmission 248, the output gear 249 of which drives the back-up roller 100 through a train of gears 250, 251, 252, 254 and 255, and the applicator roller 70 through a further variable-speed V-belt transmission 256 and gears 257, 258, 259. The roller 31 of the fountain 23 is driven by an electric motor 260 through a train of gears 262, 263, 264, 265, and the roller 30 is driven, at a lower velocity, from the roller 31, through gears 266, 267, 268, 269. The distributer rollers 71, 72, 73 are also driven from the motor 260 through gear 262 and gears 270, 271, 272, 273, 274, 275. The lower fountain 150 and distributer rollers 154 and 155 are similarly driven by a separate motor. A web break detection device is provided including switches 320, 320a, 321, 321a, which are included in an electrical circuit controlling valves for admission of compressed air or hydraulic fluid into the cylinder 116, and the corresponding cylinder on the other side. The back-up rollers 100 and 158 are normally pressed against the applicator rollers 70 and 156 by admission of fluid to the head end of the cylinders, but when a web break occurs one or more of the switches closes, causing admission of fluid to the lower end of the cylinders and drainage of the fluid from the heads and removing the back-up roller from the applicator rollers. Controls are also provided for moving the back-up rollers individually or simultaneously, independently of the occurrence of a web break. The cylinder operating the clutch of the rope-feed mechanism is also connected to the