Abstract: Fixer is detected on a print media 22 by applying a predetermined pattern 200, FIG. 3, of fixer to the media, and over or under-printing it with a fill of coloured ink, and then optically detecting the predetermined pattern. For example, magenta ink may be applied over the fixer pattern on a glossy media, areas with both fixer and ink having a detectable increase in optical density compared to areas with ink alone. The pattern is scanned and the image information is used to check fixer nozzle functionality and fixer printhead alignment.

Abstract: A brake rigging system which adequately distributes the braking force among all its components, said brake rigging system comprising: a driving beam having a first and a second end; two driving levers having a first and a second end, each driving lever rotary coupled by its first end to an end of the driving beam, and the second end of each driving lever coupled to a brake head; and linking means for linking said driving beam, to driving means which apply a force to said driving beam to push or pull said driving levers together with the brake heads.

Abstract: To check that nozzles of printheads 11-15 applying fixer or an ink to a print media 22 are operating correctly, the fixer or ink is applied to selected locations on a fluorescent print media which is then subjected to ultra-violet radiation; the reflectivities at these locations are detected in the visible spectrum and the information is analysed using appropriate image processing algorithms. In an ink-jet printer, for example, applied fixer may be irradiated with ultra-violet light by a source 30 and applied inks may be irradiated with visible light, with a common detector in the visible light range being employed.

Abstract: A test pattern is scanned to find ideal print-medium advance for a pen (or other marking device). The pattern has a medium; and, marked on it, image patches each with overlapped swaths stepped by different distances. At best there are different-color pens; and for each distance a set of patches, each with a patch for each color (preferably area fills at sensitive tones by color). All patches in a set are best adjacent along a scan direction, with alignment lines above each set across the whole pattern, and a nozzle-conditioning patch at each image patch. A processor prints the pattern, operates a sensor and uses its signals to find optimum advance. The system finds and prints with ideal advance for a most-active pen; or weighs pen activity to find an optimum for all pens based on certain statistical and/or prospective choices.

Abstract: A test pattern is scanned to find ideal print-medium advance for a pen (or other marking device). The pattern has a medium; and, marked on it, image patches each with overlapped swaths stepped by different distances. At best there are different-color pens; and for each distance a set of patches, each with a patch for each color (preferably area fills at sensitive tones by color). All patches in a set are best adjacent along a scan direction, with alignment lines above each set across the whole pattern, and a nozzle-conditioning patch at each image patch. A processor prints the pattern, operates a sensor and uses its signals to find optimum advance. The system finds and prints with ideal advance for a most-active pen; or weighs pen activity to find an optimum for all pens based on certain statistical and/or prospective choices.