公开(公告)号：US10782627B1

公开(公告)日：2020-09-22

申请号：US16443985

申请日：2019-06-18

Applicant: LEXMARK INTERNATIONAL, INC.

Inventor： Andrew Pryse Dale ,  Matthew David Heid ,  Christopher David Strack

IPC: G03G15/02 ,  G03G15/08 ,  G03G15/00 ,  G03G15/06

Abstract: An imaging device includes a photoconductive drum charged by a charge roll and opposed by developer roll. The developer roll adds toner to the drum to develop a latent image on the drum for transfer to media. One or more high voltage power supplies communicate with a controller to set voltages on the rolls. The controller determines whether imaging of the media is to occur at a time when the drum is rotating. If not, a laser beam discharges the drum and the voltage on the charge roll is decreased to reduce the charge on the drum, but the controller maintains the voltage differential between the drum and the developer roll.

公开(公告)号：US10684577B1

公开(公告)日：2020-06-16

申请号：US16207512

申请日：2018-12-03

Applicant: LEXMARK INTERNATIONAL, INC.

Inventor： Christopher Michael Bennett ,  Matthew David Heid ,  Gina Marie Johns ,  Michael Craig Leemhuis ,  Christopher David Strack

IPC: G03G15/16

Abstract: An imaging device has first image transfer from photoconductive drums to an intermediate transfer member (ITM) and second image transfer from the ITM to media. Transfer rolls oppose the drums from an opposite side of the ITM and electrically ground to a frame of the imaging device by mechanical connection. The rolls may be laterally offset from the drums. The ITM has relatively low surface and volume resistivity. An imaging subassembly may include the frame, the ITM, and the transfer rolls grounded to the frame.

公开(公告)号：US10809641B1

公开(公告)日：2020-10-20

申请号：US16518215

申请日：2019-07-22

Applicant: LEXMARK INTERNATIONAL, INC.

Inventor： Douglas Anthony Able ,  Andrew Pryse Dale ,  Jared Kuohui Lin ,  Matthew David Heid ,  Christopher David Strack

IPC: G03G15/02 ,  G03G15/16 ,  G03G15/06

Abstract: An imaging device includes a photoconductive drum charged by a charge roll and opposed by developer roll. The developer roll adds toner to the drum to develop a latent image on the drum for transfer to media or an intermediate transfer member at a transfer roll. One or more high voltage power supplies communicate with a controller to set voltages on the rolls. During times of non-imaging, but rotation of the drum, the charge roll charges the drum to less than a Paschen breakdown voltage of the drum. A voltage of the transfer roll is determined that corresponds to a temperature and relative humidity of an operating environment of the imaging device and the developer roll is charged based thereon. The charge of the transfer roll is set close to the charge of the drum, but higher in magnitude. A laser may also discharge the drum.