Abstract: A feeder device for feeding powder, having a barrel feeding channel with a downstream end. The feeding channel including at least one conveying element for conveying the powder material to the downstream end. A rotatable exit element provided at the downstream end of the feeding channel. The rotatable exit element includes an annular portion defining exit openings defined by powder engaging edges. The rotatable exit element is positioned transversally outside the barrel in a proximity of the downstream end of the feeding channel. The feeding channel has a first, inner diameter and the rotatable exit element has a second, outer diameter, where the second, outer diameter is equal to or larger than the first inner diameter.

Abstract: A feeder device for feeding powder, having a barrel feeding channel with a downstream end. The feeding channel including at least one conveying element for conveying the powder material to the downstream end. A rotatable exit element provided at the downstream end of the feeding channel. The rotatable exit element includes an annular portion defining exit openings defined by powder engaging edges. The rotatable exit element is positioned transversally outside the barrel in a proximity of the downstream end of the feeding channel. The feeding channel has a first, inner diameter and the rotatable exit element has a second, outer diameter, where the second, outer diameter is equal to or larger than the first inner diameter.

Abstract: A coating device for coating a peripheral surface of a sleeve body with a coating formulation includes a vertical support column for supporting a sleeve body in a vertical position coaxial with a coating axis, a carriage slideable along the vertical support column, and an annular coating stage attached to the carriage and moveable therewith for containing the coating formulation and for coating a layer of the coating formulation onto the peripheral surface of the sleeve body during a sliding movement of the carriage along the vertical support column. The coating device includes an irradiation stage that is arranged to be moveable with the annular coating stage and to provide radiation to at least partially cure the layer of coating formulation onto the peripheral surface so as to prevent flow off of the coating formulation.

Abstract: A coating device for coating a peripheral surface of a sleeve body with a coating formulation includes a vertical support column for supporting a sleeve body in a vertical position coaxial with a coating axis, a carriage slideable along the vertical support column, and an annular coating stage attached to the carriage and moveable therewith for containing the coating formulation and for coating a layer of the coating formulation onto the peripheral surface of the sleeve body during a sliding movement of the carriage along the vertical support column. The coating device includes an irradiation stage that is arranged to be moveable with the annular coating stage and to provide radiation to at least partially cure the layer of coating formulation onto the peripheral surface so as to prevent flow off of the coating formulation.

Abstract: In a digital printer the elements involved directly in the print process, which are located on a shuttle assembly are mounted upon a metrological frame which is isolated from the base frame by vibration dampers. Because the elements of the shuttle drive systems, such as a belt drive system having a motor and pulleys, are mounted upon the base frame, the drive and reaction forces from the motor drive systems are led to the base frame while the shuttles assembly is guided by the force-free, vibration free metrological frame. This allows for higher accuracy during printing as the metrological frame serves as a vibration free reference element.

Abstract: A digital printer includes a digital printing unit for digital printing an image onto a printing substrate during relative movement between a print head and the printing substrate, and a printing table for holding the printing substrate during the digital printing. The printing table is firmly fixed to the digital printing unit during the digital printing of the image onto the printing substrate and is released from the digital printing unit prior to and after the digital printing of the image onto the printing substrate. The printing table may be moved between a printing position, in which it is firmly fixed to the digital printing unit, and a printing substrate feeding position, in which it supports feeding and removing of the printing substrate from the printing table.

Abstract: An ink circulation system for use in an inkjet printing apparatus includes an inkjet printhead, an ink supply path for supplying an ink to the inkjet printhead and an ink return path for returning ink not used for printing from the inkjet printhead. The ink return path is coupled to the ink supply path for replenishing the ink supply path with the ink returned from the printhead. The coupling establishes an ink circulation circuit. The ink circulation circuit can be replenished with fresh ink from a main tank, as ink is withdrawn by the printhead for printing. In the circulation system an active through-flow ink degassing unit is provided to control the dissolved gas level of the ink in the ink circulation system.

Abstract: A printhead positioning system is provided wherein the shuttle assembly is split up in a printing shuttle, having a high accuracy positioning capability and a utility shuttle needing only a low accuracy positioning system. Due to this split-up the mass of components which have to be positioned accurately is greatly reduced and therefore making it easier to position the lighter load accurately and allowing for use of cheaper drive systems while maintaining the high accuracy in printing.

Abstract: Upon a substrate subsequent layers of elastic ink are jetted using an ink jet printing system. Each layer is immobilised by a immobilisation step before jetting the following layer. A printing relief is gradually formed to obtain a flexographic printing plate allowing accurate control over the relief and slopes of the printing plates. Use can be made of different inks or immobilisation step to obtain different layer characteristics. Inks can be immobilised using UV curing. The recorded relief of the layers can be measured and corrections can be applied using a feed-back loop. A rejuvenation process for printing plates can be constructed using the described method. An elastic base layer can be provided on the substrate to provide better plate characteristics.

Abstract: A print head mounting assembly and a method of mounting and positioning a print head on a print head carriage framework suitable for mounting in a printing system includes a print head positioning device for receiving a print head, and a print head mounting tile having a mounting surface for mounting the print head positioning device. The print head mounting tile is adjustably mounted on the print head carriage framework such that it provides a mounting surface for the print head positioning device that is level with a reference printing surface, when the print head carriage framework is mounted in the printing system. The print head positioning device is adjustably mounted on the print head mounting tile such that the print head, being received in the print head positioning device, is accurately positioned on the mounting surface of the print head mounting tile.

Abstract: A receiver table (1) is provided for holding a receiver in a digital printer using a shuttle (2) carrying the printheads (3), e.g. an ink-jet printer, which is divided in small table segments (5) of which height and orientation can be adjusted. By adjusting the segments (5) the table (1) can be deformed to obtain a constant receiver-printhead distance even if the guidance of the shuttle (2) has deviations or exhibits bending during shuttling. Table segments (5) are preferably mounted on a deformable table support (13). The receiver-printhead “throw distance” can be calibrated by measuring the distance profile and adjusting adjustments screws or bolts to align the table segments (5) to the ideal printing distance.

Abstract: A step-wise medium transport system is provided having high accuracy for transporting recording media in a digital printer, the medium is transported using accurately moving tables to which the medium is attached during printing steps the working area of the medium, on which the printing is done by the printer, is at all times fully supported by a static table avoiding disturbances.

Abstract: A print head mounting assembly and a method of mounting and positioning a print head on a print head carriage framework suitable for mounting in a printing system includes a print head positioning device for receiving a print head, and a print head mounting tile having a mounting surface for mounting the print head positioning device. The print head mounting tile is adjustably mounted on the print head carriage framework such that it provides a mounting surface for the print head positioning device that is level with a reference printing surface, when the print head carriage framework is mounted in the printing system. The print head positioning device is adjustably mounted on the print head mounting tile such that the print head, being received in the print head positioning device, is accurately positioned on the mounting surface of the print head mounting tile.

Abstract: To avoid possible damaging collisions of a printhead with small receiver defects and other obstacles in a digital printer using a printhead mounted on a scanning shuttle for recording an image on a receiver while scanning along the receiver, a method using the following steps is used:—sensing for possible obstacles having a size smaller and larger than the inkjet head-receiver clearance distance in an area of the receiver to be scanned over by the printhead using a sensor system mounted on the scanning shuttle,—avoiding a collision of the printhead with the obstacle when an obstacle is sensed. Preferably an evaluation step is include to evaluate is a detected obstacle is evaluated to be potentially damaging. A system for using the steps is also disclosed.

Abstract: A step-wise medium transport system is provided having high accuracy for transporting recording media in a digital printer,—the medium is transported using accurately moving tables to which the medium is attached—during printing steps the working area of the medium, on which the printing is done by the printer, is at all times fully supported by a static table avoiding disturbances.

Abstract: A coating device for coating a peripheral surface of a sleeve body with a coating formulation includes a vertical support column for supporting a sleeve body in a vertical position coaxial with a coating axis, a carriage slideable along the vertical support column, and an annular coating stage attached to the carriage and moveable therewith for containing the coating formulation and for coating a layer of the coating formulation onto the peripheral surface of the sleeve body during a sliding movement of the carriage along the vertical support column. The coating device includes an irradiation stage that is arranged to be moveable with the annular coating stage and to provide radiation to at least partially cure the layer of coating formulation onto the peripheral surface so as to prevent flow off of the coating formulation.

Abstract: A method and apparatus for aligning the printing of dots generated by at least one array of printing elements of a printing apparatus. The method includes the steps of printing a calibration test pattern, scanning the printed calibration test pattern, determining at least one calibration value based on the scanned calibration test pattern, and adjusting the alignment of the array of printing elements based on the determined calibration value. The step of scanning the printed calibration test pattern further includes automatically positioning a camera relative to the printed calibration test pattern and imaging a detail of the printed calibration test pattern within the field of view of the camera.

Abstract: A printhead positioning system is provided wherein the shuttle assembly is split up in a printing shuttle, having a high accuracy positioning capability and a utility shuttle needing only a low accuracy positioning system. Due to this split-up the mass of components which have to be positioned accurately is greatly reduced and therefore making it easier to position the lighter load accurately and allowing for use of cheaper drive systems while maintaining the high accuracy in printing.

Abstract: In a digital printer the elements involved directly in the print process, which are located on a shuttle assembly are mounted upon a metrological frame which is isolated from the base frame by vibration dampers. Because the elements of the shuttle drive systems, such as a belt drive system having a motor and pulleys, are mounted upon the base frame, the drive and reaction forces from the motor drive systems are led to the base frame while the shuttles assembly is guided by the force-free, vibration free metrological frame. This allows for higher accuracy during printing as the metrological frame serves as a vibration free reference element.

Abstract: A receiver table (1) is provided for holding a receiver in a digital printer using a shuttle (2) carrying the printheads (3), e.g. an ink-jet printer, which is divided in small table segments (5) of which height and orientation can be adjusted. By adjusting the segments (5) the table (1) can be deformed to obtain a constant receiver-printhead distance even if the guidance of the shuttle (2) has deviations or exhibits bending during shuttling. Table segments (5) are preferably mounted on a deformable table support (13). The receiver-printhead “throw distance” can be calibrated by measuring the distance profile and adjusting adjustments screws or bolts to align the table segments (5) to the ideal printing distance.