Xerox 3150 - Phaser B/W Laser Printer, Руководство по обслуживанию

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Summary of Product
4-6
4.2.4 Transfer Assembly
The transfer roller transfers toner from the OPC drum to the paper. Toner is transferred from the OPC drum onto the
paper using a PTL (Pre-Transfer Lamp) and a transfer roller. The PTL shines light onto the OPC, reducing the
electrical charge on the OPC surface improving the efficiency of the transfer.
The transfer assemblies life span is 60,000 sheets.
4.2.5 Drive Assembly
The drive assembly receives power from the main controller board. The main motor powers the paper feed, toner
cartridge, fuser unit and all pick-up, feed, and exit rollers.
4.2.6 Fuser Assembly
The fuser assembly uses a heat lamp process. This consists of a heat lamp, heat roller, pressure roller, thermistor, and
thermostat. By use of heat and pressure, toner is melted to adhere to the paper surface in order to complete the
printing process.
4.2.6.1 Thermistor and Thermostat
The thermistor is used to detect the temperature of the heating unit and feeds this information into the main processor.
If the heat lamp becomes too hot, the thermostat cuts off the power to the lamp in order to prevent overheating and
any potential fire hazard is removed.
4.2.6.2 Heat roller
The heat roller transfers the heat from the heat lamp to the paper. The surface of the heat roller is coated with Teflon
so that toner does not stick to the surface.
4.2.6.3 Pressure roller
A pressure roller, mounted under the heat roller, is made of a silicon resin and the surface is also coated with Teflon.
When paper passes between the heat roller and the pressure roller the toner powder is melted and permanently fixed
to the surface of the paper.
4.2.6.4 Safety features
To prevent overheating:
■ 1st protection device: Hardware cuts off when overheated.
■
2nd protection device: Software cuts off when overheated.
■ 3rd protection device: Thermostat cuts off main power to the lamp.
Safety device
■
Fuser power is cut off when the front cover is opened.
■ Laser power is cut off when the front cover is opened.
■
The temperature of the fuser cover's surface is maintained at less than 80º C to protect the user. A caution
label is attached where the customer can see it easily when the rear cover is opened.