For needle-type printers, the causes of blank paper are mostly due to dry ribbon ink, ribbon breakage, print head damage, etc., should be replaced or repaired in time; for inkjet printers, the printing blank caused by the fault is mostly due to nozzle blockage, ink cartridge no ink, etc., should be cleaned or replaced ink jet head. If the cartridge is refitted with continuous ink supply, it may be that the air permeability hole of the outer cartridge is not opened. The air permeability hole should be left on the outer cartridge.
For laser printers, the reason may be that the development roller does not absorb toner (the development roller does not add the DC bias), or the drum is not grounded, so that the negative charge can not be released to the ground, the laser beam can not play a role in the drum.
In addition, the photosensitive drum of the laser printer does not rotate, and no image is generated and transmitted to the paper. Disconnect the power supply of the printer, remove the toner cartridge, open the slot on the lid of the cartridge, mark the non-sensitive part of the photosensitive drum and re-load it into the machine. Start running for a while, and then take out the check mark is moving, you can judge whether the drum is working properly. If toner can not be supplied normally or laser beam is blocked, printing blank paper will also appear. Therefore, it is necessary to check whether the toner has been used up, whether the cartridge has been properly loaded into the machine, whether the sealant tape has been removed or whether there is a shield on the laser irradiation channel. It should be noted that the power supply must be turned off during the inspection because the laser beam may damage the operator's eyes.
Printing paper output black
For needle printer, the cause of the trouble is strip depilation, too much ink on the ribbon, dirty printing head, poor quality of the ribbon and the position of the push rod adjust too close, when overhauling, should first adjust the position of the push rod, if the fault can not be eliminated, then replace the ribbon, cleaning the print head, in general can be troubleshooting;
For inkjet printers, it is important to check whether the nozzle is damaged, whether the ink pipe is broken, whether the type of ink is normal, etc. For laser printers, it is mostly due to corona discharge wire failure or control circuit failure, so that the laser has been emitting, resulting in print output content black. Therefore, it is necessary to check whether corona discharge wire has been disconnected or corona high voltage exists, and whether the beam detector in the laser beam path works properly.