| 摘要 |
Ink is picked up by an ink roller which has a surface characterized as consisting of a foamed plastic with pores open at the outer circumference but not interconnected. The ink roller dips into ink within an ink trough. The ink being applied to the ink roller is controlled by stripping elements formed as rollers which are pressed with controllable force against the surface of the ink pick-up roller; the force can be controlled, for example, by pneumatic or hydraulic fluid means, such as pressure piston-cylinder arrangements, blow-up pillows, or fluid pressure being applied against the roller mechanism directly; or by mechanical means, such as by a spring suspension in which the attachment points of the springs are selectively positionable. Preferably, the stripping rollers are about 1/15 or less of the diameter of the ink pick-up roller, and driven at a circumferential speed which is slow with respect to that of the ink pick-up roller. Ink can be transferred directly to a printing plate cylinder, or to ink transfer rollers. Both the ink pick-up roller and the stripping roller, preferably, are axially oscillating. |
