PAPER/IMAGE HANDLING ON AN ELECTROSTATIC MASTER DUPULICATOR FOUR COLOR PRESS
Original Publication Date: 1991-Feb-28
Included in the Prior Art Database: 2004-Apr-05
Xerox Disclosure Journal
A method of handling paper and maintaining registration in a four color press is to "hand-off the print sheet to gripper drums between color stations. Registration of better than 0.005 Dia. can be maintained by this method. In xerographic machines this is not easily achieved because the unfused image comes in contact with transport drums. In this disclosure as shown in the figure, a paper gripper 1 is mounted on two supporting arms 2 on either side of the paper path. The arms are mounted to a shaft which is connected to the machine drives. The gripper arrangement is positioned between the transfer drums 3 of the color stations and grips the paper after the first image is transferred. The second gripper grips the paper before the first gripper releases it, thereby maintaining registration. Once the second gripper has control of the paper, the first gripper then releases the paper and thus "hand-off' is complete. A vacuum chamber 4 attracts the non-image side of the paper with a gentle force, thereby maintaining registration. The vacuum also maintains control of the paper and prevents the paper from contacting other machine components and avoiding image smear.