摘要:
This invention generally relates to accurately measuring image geometries in-line within a printing system. One or more two-dimensional array sensors may be located adjacent to a sheet of media printed with a predefined array of indicia marks so that the sensor field of view is contained within the plane of sheet transport. As the sheet is transported by the sensor, the sensors continuously record the locations of the indicia marks within its field of view. The spatial frequency of the indicia marks is arranged so that at least two indicia marks are within the field of view of the sensor at any instant for each of the process and cross-process directions. The two-dimensional array sensor can thus measure the absolute spacing between adjacent local indicia marks within the precision of the sensor construction. The cumulative spacing along each direction may then calculated to determine the overall dimensions of the indicia marks array. A measurement procedure is also provided to accurately measure image geometries, even in the presence of significant sheet velocity variations.
摘要:
A drive roll/idler roll nip release mechanism utilizes the motor used for the drive nip, coupled with one-way clutches, to power the nip release as a sheet is handed off to a downstream nip. A drive shaft is coupled to a first one-way clutch in one direction and an idler cam shaft is coupled to a second one-way clutch in the opposite direction. This allows the idler cam shaft to be driven only when the motor is reversed, and the drive shaft to be driven only when the motor is moving forward. The one-way clutch on the drive shaft allows the drive wheels to freewheel when the motor is reversed in order to engage the nip release. Thus, the nip release is activated while the drive nip continues to rotate in the direction of sheet motion.
摘要:
A compiling unit includes a collection tray and a variable-speed compiling system adapted to operate at at least two speeds to thereby receive a sheet of media at a higher speed and register the sheet of media within the collection tray at a lower speed. A control system is adapted to selectively operate the variable-speed compiling system at the at least two speeds. A printing system having a sheet media source, at least one marking engine, such a compiling unit and such a control system is included. A method of compiling sheet media is also included.
摘要:
A system for support, operation, installation, and removal of an endless belt in a scalable modular printing system includes an input module, at least one marking module, and an output module. The endless belt is an intermediate transfer belt, a photoconductive belt, or a sheet transport belt used in the marking system. Rollers support an interior surface of the belt, and are supported by their respective module frame structures, thus defining a vacant interior cavity of the belt. A method of belt installation includes drawing all interior rollers out of their frame structures, placing the pre-scrolled belt at one end module of the system, uncoiling the belt along its process direction within the internal cavity of the system, then reinstalling the interior rollers to capture the belt into its operating position.
摘要:
A method to reduce the misalignment between the image one and image two printed on the same or opposing side of the same sheet. The final error (skew, process and cross-Process) between the actual sheet orientation and the desired orientation during the transfer of an image while printing image one is measured and recorded. When the same sheet comes for printing image two, the error recorded during image one printing is retrieved and used to compensate the desired angular, process and cross-process registration of the sheet for image two printing so that the alignment of image one and image two is improved in comparison to systems that register the sheet without considering image one imaging errors.