| 摘要 |
DAMPENING APPARATUS FOR AN OFFSET LITHOGRAPHIC PRINTING MACHINE The invention provides dampening apparatus for an offset lithographic printing machine, comprising at least one rotatable disc for spraying dampening agent, and at least one first dampening roller for receiving the dampening agent from the rotatable disc or discs, wherein the apparatus further comprises an inking roller for applying ink to a printing cylinder or plate; at least two additional dampening rollers, the additional rollers comprising a second dampening roller which has a resilient surface and is arranged to receive dampening agent from the first dampening roller and a third dampening roller which is arranged to receive dampening agent from the second dampening roller, the inking roller being arranged to receive dampening agent from the third dampening roller; and means for providing that the first, second and third dampening rollers rotate at fixed relative rotational speeds and that the peripheral speed of the first dampening roller is lower than that of the second dampening roller such that when the first and second dampening rollers are in contact with each other and rotating the peripheral surface of the first roller slips relative to that of the second roller. The invention enables a suitable balance of ink and dampening agent to be obtained. |
