Xerox C2424 Service Manual - Page 82

Purge System Proper printhead operation is dependant on the correct operation of the purge system. The purge system uses air pressure and a wiper blade to purge any debris or air bubbles that may be obstructing the printhead nozzles. The waste ink that is expelled during the purge is funneled into the waste tray. Following the purge, a wipe operation is performed on the faceplate using the wiper blade. After the wipe, a cleaning page is printed. Wiper Blade Printhead Purge Tube 2.5 Sec Purge Pump s2424-042 To perform a printhead maintenance cycle, the printhead is first tilted away from the drum to allow the wiper assembly to pass by. The wiper blade is then raised in front of the printhead. The media path drive governs wiper movement when it engages a clutch on the exit shaft of the printer. The purge pump applies pressure to the ink reservoir for approximately 2.5 seconds. Valves in the reservoir seal when pressure is applied. The pressurization ejects a small amount of ink from the jets. Following the pressure purge, the printhead tilts into the wiper assembly and the wipe cycle begins. The pump runs again with the solenoid for approximately 30 seconds, creating a neutral balance between pressure and ink. The wiper blade lowers and wipes excess ink from the jets into the ink waste tray. A proper purge covers the length of the waste tray with a single layer of ink about 20 mm wide. 2-38 WorkCentre C2424 Service Manual