Xeikon N.v.

Erik Gabriel Van Weverberg

Etienne M De Cock

Lucien A De Schamphelaere

Peter Alexander Steylaerts

Ronny Jean Aerens

Jan Julien De Bock

Patrick Billet

Erik Marcel Bollansee

Louis Luyckx

The printer has at least two printing stations which cause images to be printed on a substrate. The printer is capable of registration adjustment. First and second patterns of spaced registration marks are printed onto the substrate by operation of the printing stations. The second pattern partially overlaps the first pattern to form a composite pattern of registration marks. The composite pattern is illuminated and the reflectivity thereof is examined at wavelengths complementary to the colors of the first and second patterns to obtain a reflectivity signature for the composite pattern. The reflectivity signature of the composite pattern (120) is compared with a predetermined signature to determine an adjustment factor for the printer.

Method for monitoring registration of images printed by a printer

Printer for printing images on a substrate web

An electrostatographic single-pass multiple station multi-colour printer for forming an image onto a web. The printer has a plurality of toner image-printing electrostatographic stations. Each station has a drum onto the surface of which a toner image can be formed. An exposure station forms an electrostatic toner image line-wise on each drum surface. A corona device transfers the toner image onto the web, which is conveyed in succession past the stations in synchronism with the rotation of the drum surface. A register control device is provided for controlling the operation of each of the stations in timed relationship thereby to obtain correct registering of the distinct toner images on the web. The register control device includes an encoder driven by the displacement of the web to produce pulses indicative of web displacement, and delay system arranged to initiate the operation of subsequent stations after a predetermined web displacement, as measured by the encoder, has occurred. The invention enables accurate registration of the transferred images, irrespective of the speed of the paper web through the printer.

Electrostatographic single-pass multiple station printer and method with

A method of forming a drum assembly for use as a rotatable endless surface onto which a toner image is formed. The drum assembly has a hollow drum with an opening at each end and a surface onto which the image is formed. A support flange, having an aperture in the center thereof, is cooled before being inserted into each end opening. The drum assembly also includes a shaft having a collar fixed in the vicinity of each end. After the shaft is positioned inside the drum, the collars are positioned to coincide with the flange apertures. Screws secure each collar to its respective flange. The screws can be adjusted to reduce the eccentricity of the drum.

Method of forming a drum assembly for use in a printer and the drum

Electrostatographic image reproduction apparatus forms images of toner particles on a receptor material moving along a transport path. A rotatable contact roller contacts the receptor material while it has an electrostatically charged toner particle image on at least the adjacent surface thereof. The contact roller is selected from a receptor material transport roller, a guiding roller, and a reversing roller. Electrostatic charging device provide an electrostatic charge, having the same polarity as the charge polarity of the toner particles, on the surface of the contact roller before contact of the receptor material with the surface of the contact roller. Cleaning means remove any toner particles from the surface of the roller after release of the receptor material from the surface of the contact roller. Smudging of the toner image on the receptor material is reduced.

Guiding or reversing roller arrangement for an electrostatographic image

An electrostatographic printer includes an imaging station for forming a latent electrostatic image on the surface of a drum, a toner development station for developing the latent image to form a toner image, and a toner transfer station for transferring the toner image onto a moving web. An image-fixing station for fixing the toner image on the web includes two pairs of radiant heat sources, the peak energy output wavelength of which lies in the non-visible part of the spectrum. The radiant sources may be located in hingedly mounted pairs of housings in such a manner that the housings may be moved into a closed position to shield the radiant sources from the web when the speed of movement of the web falls below a predetermined value. Thus, damage to the web when movement of the web stops is avoided.

Electrostatographic printer with image-fixing station

An electrostatographic single-pass multiple station multi-color printer for forming an image onto a web has a plurality of toner image-printing electrostatographic stations. Each station has a drum onto the surface of which a toner image can be formed. An exposure station forms an electrostatic toner image line-wise on each drum surface. A corona device transfers the toner image onto the web, which is conveyed in succession past the stations in synchronism with the rotation of the drum surface. Register control apparatus provided for controlling the operation of each of the stations in timed relationship thereby to obtain correct registering of the distinct toner images on the web. The register control apparatus comprises an encoder driven by the displacement of the web to produce pulses indicative of web displacement, and a delay arranged to initiate the operation of subsequent stations after a predetermined web displacement, as measured by the encoder, has occurred. The invention enables accurate registration of the transferred images, irrespective of the speed of the paper web through the printer.

Growing community of inventors

Mortsel, Belgium

Erik Gabriel Van Weverberg