How does a laser printer fuser work?
What makes up the fusing process?
The two main factors that make the fusing process work are heat and pressure. After going through the drum of the laser printer where the ink is placed on the paper, it then goes through the two rollers which make up the fuser.
How does the fuser heat up?
To reach the temperature needed, a quartz tube lamp is warmed up inside the roller responsible for heat. This lamp is thermostatically controlled and begins the heating process as the laser printer is turned on. This lamp cools down and remains cooled whilst the printer is in sleep mode.
How does the image get to the paper and stay there?
The drum is responsible for placing the plastic based toner electrostatically on the paper. After it gets to the fuser, the heat roller melts the toner and then as it goes through the roller responsible for pressure, it is bonded to the paper. The same process occurs for photocopiers to produce their finished sheets.
The fuser unfortunately is where problems with laser toner printers frequently occur. A variety of things can happen to make it malfunction such as an accumulation of paper dust or of toner residue. When this happens, it results in scratches on the roller which can then leave unsightly marks on your paper. A large scratch can cause toner to be unevenly distributed on the paper and leave large smears. Other things that can occur are the quartz lamp bulb burning out, or the thermostat going wrong.
How do you replace the fuser?
The first thing to do before replacing a fuser, is to let it cool off completely before attempting any repairs. A heated fuser can reach temperatures of a few hundred degrees! Once removed, it will be much easier to remove any debris or dust from the inside of the machine. If your printer provides any information in regards to a fuser error, it is most likely that the fuser did not heat properly; it either got too hot or not hot enough.
How much does it cost?
Replacing a laser printer fuser is not usually a cheap option. A properly working fuser can yield up to as much as 100,000 pages. Depending on the brand, you can find a fuser assembly for as little as £50 and as much as £300!