Patent ID: 6367380
Filing Date: 2002-04-09
Classification: B41F,Y10S

Abstract:
An inking system comprising:an ink transfer roller having a first axis about which the ink transfer roller is rotatable, the ink transfer roller having a periphery for receiving ink from an ink supply; an ink transfer belt having an ink transfer surface and an opposite drive surface, the ink transfer surface being in contact with the ink transfer roller at a first nip for transferring ink from the ink transfer roller onto the ink transfer surface; a first belt guide roller having a periphery located for engaging the drive surface of the ink transfer belt and for urging the ink transfer surface of the ink transfer belt against the ink transfer roller to define the first nip; a second belt guide roller having a periphery located for engaging the drive surface of the ink transfer belt for urging the ink transfer surface of the ink transfer belt against a printing plate for defining a second nip and for transferring ink from the ink transfer surface of the ink transfer belt to ink receiving elements on the printing plate; the first and the second guide rollers having respective axes and being rotatable about their respective axes; a rotation drive connected with at least one of the guide rollers for driving the one guide roller connected to the drive to rotate the periphery thereof at a first speed, and the periphery of the one guide roller being in contact with the drive surface of the ink transfer belt for driving the belt to move at the peripheral speed of the one guide roller; an ink distribution roller having a peripheral ink distribution surface in contact with the ink transfer surface of the ink transfer belt at a location between the first and second nips on the portion of the surface of the ink transfer belt carrying ink, the ink distribution surface being adapted to rub the ink on the ink transfer surface of the belt as the ink transfer surface of the belt moves past the ink distribution roller; the ink distribution roller having a rotation axis about which the ink distribution roller is rotated and having a periphery which rotates in engagement with the ink transfer surface of the ink transfer belt; a drive to the ink distribution roller for rotating the ink distribution roller so that the ink distribution surface rotates at a speed different than the speed of the ink transfer surface of the belt as the belt moves past the ink distribution roller for aiding in the distribution of the ink on the ink transfer surface of the belt; wherein the ink transfer belt is an endless loop belt having an exterior surface which is the ink transfer surface and having an interior surface, which is the drive surface of the belt; further comprising a third guide roller spaced from the first and second guide rollers, located inside the loop of the ink transfer belt, in engagement with the drive surface of the ink transfer belt and having a rotation axis about which the third guide roller is rotatable; the third guide roller having a respective periphery also in driving engagement with the drive surface of the ink transfer belt, so that the ink transfer belt and the peripheral surfaces of the first, second and third guide rollers move at the same velocity and in the same direction; and further comprising a second one of the ink distribution rollers spaced from the first mentioned one of the ink distribution rollers, and the second ink distribution roller having a respective second axis about which the second ink distribution roller rotates and having a respective second peripheral surface in engagement with the ink transfer surface of the ink transfer belt.