GB608785A - Improvements in and relating to mechanisms for applying liquids to sheets - Google Patents

Abstract

<PICT:0608785/III/1> <PICT:0608785/III/2> <PICT:0608785/III/3> A mechanism for applying liquid to a sheet of paper or the like comprises a capillary pad arranged in contact with a liquid-applying roller adapted to apply the liquid to a sheet passing between it and a further roller, wherein said capillary pad is of flat sheet form and is carried in a rigid tray which is movably supported in a manner whereby the capillary pad is inclined upwardly towards said liquid-applying roller and is movable in its own plane so as to present its uppermost longitudinal edge into abutting relationship to said roller. Referring to the drawings, a sheet of paper is fed between a damping roller 3 and a counter-roller 4. Gear-wheel 5 on roller 3 meshes with gear-wheel 6 journalled in rocking level 7 pivoting freely about the axis of roller 3 between stops 9 and 10. Spring 8 urges lever 7 towards stop 10 and in this position gear-wheel 6 engages toothed segment 11 on printing drum 1 so advancing the sheet to be gripped between drum 1 and pressure roller 2. Segment 11 then runs off gear-wheel 6 and the damping roller 3 is rotated only by contact with the sheet. Roller 3 is supplied with liquid from felt pad 36 supported in case 37, inclined upwardly towards damping roller 3. Liquid is supplied to the pad by pump 21, 22 operated automatically by drum 1. For this purpose a stop 12 on drum 1 engages lever 16 mounted on a pivot pin 20 and so engages the piston-rod and lifts piston 21 against the action of spring 31, then the release of lever 16 by stop 12 causes piston 21 to return to its original position, thus pumping liquid via pipe 26. The length of the stroke is regulated by a stop lever 29 mounted on a pivot 30 which can be fixed in one of a series of positions. Pipe 26 is connected to the inner of two concentric pipes 32 and 34, the inner pipe having a small number of coarse apertures 33 along its width and the other a large number of small apertures 35. Pad case 37 fits into guides 39 and can move freely in the guides by means of rollers 38 and can be removed therefrom through holes 40. The pad 36 is held in contact with roller 3 by means of spring 41. A cover-plate 43 extends upwardly from the pad and encloses the pipes 32 and 34 and contains an auxiliary pad 42 serving both to enlarge the fluid absorbing capacity and to prevent sudden variations in the fluid supplied to roller 3 by pad 36. Surplus liquid fed to the pad flows through a drainage hole 44 in the base of case 37 and through a pipe 45 back to reservoir 23.