Abstract:
A defect analysis system for a xerographic print engine includes a residual mass sensor that senses the two-dimensional signature structure of residual mass remaining on a photoconductive or other substrate surface after image transfer. Preferably, the sensor is a full width array that spans substantially an entire width of the photoconductive surface. This information is then processed and analyzed to determine a specific type of transfer defect present. This may include the quantified level of defect for each detected type. The defect analysis system may also include a closed-loop control system that can adjust various xerographic process parameters using feedback based on the identification and optionally magnitude of each specific defect type. The identified print quality defect, such as mottle, streaks, point deletions, graininess, etc. can then be used to determine a customized corrective control action to be taken by the feedback control of the xerographic print engine to remedy or compensate for the defect(s).
Abstract:
Embodiments herein generally relate to printing systems and methods that use toner and more particularly to a system and method that observes the distribution, for different levels of transfer field, of mass per area of toner remaining on the drum/belt as the drum/belt transfers the toner. The distribution is compared to predetermined standards and/or other networked printing systems to evaluate characteristics of the toner. Actuators can then be used to improve the toner characteristics resulting in improved print quality within a printing system and improved printing consistency between internally or externally networked printing systems and/or marking engines.
Abstract:
An electrostatographic printing apparatus comprises a charge receptor, and a transfer station for transferring a toner image from the charge receptor to a sheet by providing an electric field of predetermined magnitude at a transfer zone. The transfer station includes a rotatable transfer member, with a cleaning corotron associated therewith. A control system for maintaining a constant current at the transfer zone takes into account a current supplied by the cleaning corotron. The control system can also take into account current leakages associated with the transfer member.
Abstract:
An electrostatographic printing apparatus comprises a charge receptor, and a transfer station for transferring a toner image from the charge receptor to a sheet. The sheet passes through a nip formed between the charge receptor and a moving transfer belt. Upstream of the nip, the belt forms a shallow angle relative to the charge receptor; downstream of the nip, the belt forms a steep angle relative to the charge receptor. This configuration enables self-stripping of the sheet from the transfer belt at the exit of the nip.
Abstract:
Electrodes are embedded in a biased charge roller of a xerographic device. The electrodes, which may run the length of the roller, are deposited on an insulating substrate. A semi-conductive conformable layer of a flexible elastomer covers the electrodes. The semi-conductive conformable layer limits current flow between electrodes and relaxes charge deposited on the roller surface. Stationary pre-nip and post-nip contacts apply the bias to the imbedded electrodes. The electrodes in the post nip region are biased to VPOST. The electrodes positioned in the pre-nip regions are either grounded or biased to VPRE