Automatic mob sensor timing adjustment

摘要

When reading calibration chevrons during mark-on-belt (MOB) sensor timing calibration, cyan portions or legs of printed chevrons are detected in order to determine a timing window offset adjustment. Depending on which of the six cyan legs on the left side of the chevrons are detected, a determination can be made regarding whether the window needs to be started earlier or later. If only the first two cyan legs on the left side of the chevron are detected, then the MOB sensor timing window is beginning (and ending) too early and an appropriate adjustment can be made to cause the timing window to initiate later. If only the last two cyan legs on the left side of the chevron are detected, then the MOB sensor timing window is beginning (and ending) too late, and appropriate adjustment can be made to cause the timing window to initiate earlier.

主权项

1. A computer-implemented method for calibrating the timing for a mark-on-belt (MOB) sensor, comprising:
marking a photoreceptor belt with cyan portions of at least a first and second calibration chevron ensembles; using nominal timing, reading the first and second calibration chevron ensembles during a predefined sensor read window; analyzing a first signal from an outboard MOB leg of an outboard MOB that measures and outboard side of the first calibration chevron ensemble, and analyzing a second signal from an outboard MOB leg of an inboard MOB that measures an outboard side of the second calibration chevron ensemble; and for each chevron ensemble read, determining whether there are N cyan portions, where N is an integer, seen during the read window; wherein N cyan portions are detected in each read window, and further comprising: computing an average for the time from a start of the read window to the first detected cyan portion for each of M captures, where M is an integer; calculating a difference between the computed average and an expected distance value for the nominal start of the read window to the first chevron ensemble; and adjusting a MOB read window offset value as a function of the calculated difference thereby centering the read window on the chevron ensembles.