Major Iot Assemblies - Xerox Phaser 4620 Service Manual

To better understand Fuser errors, Fuser components are described below.
Table 4 Fuser Components
Component Function
Heat Roller The Heat Roller is a metal tube with a coated surface and a Heat
Lamp inside. As media passes between the Heat Roller and Pres-
sure Roller, the heat fuses the toner to the media.
Pressure Roller The Pressure Roller maintains pressure on the media passing
between it and the Heat Roller. This pressure bonds the melted
toner to the paper.
Heat Lamp The Heat Lamp is a quartz glass tube containing heater coils. The
Heat Lamp heats the entire length of the Heat Roller.
Temperature Sensors These are Thermistors having a known value of resistance that
varies with temperature. There are three Temperature Sensors in
the Fuser. One is located at the center of Heat Roller, the other is
located where the edge of a letter size sheet of paper comes
through. The third is located at the center of the Pressure Roller.
The sensors monitor the surface temperature of the Heat and
Pressure Rollers.
Thermostat The Thermostat provides a second-level of protection. If the Heat
Roll temperature exceeds the preset temperature, the Thermostat
cuts off the AC power to the Heater Rods.
Fuser Exit Sensor This sensor detects the arrival of the paper at the Fuser exit.
Fuser Life Expectancy
The life expectancy of the Fuser is 300,000 Letter/A4 size pages. Several factors can reduce
Fuser life:
• Greater than 5% coverage
• Printing on heavy media
• Printing on transparencies or specialty media
Power Shutoff to the Fuser
The printer shuts off power to the Fuser for the following reasons:
• Fuser error
• Jam error
• Cover or doors open
• Laser Unit error
• CPU or NVRAM error
• Fuser Fan error
Revision - Xerox Internal Use Only
Phaser 4600/4620 Printer Service Manual

Major IOT Assemblies

Components of the Phaser 4600/4620 printer described in this section include:
• Trays
• Duplex Unit
• Exit Assembly
• Drive and Electrical
Trays
Standard trays include the 100-sheet, multi-purpose Tray 1 and 1 520-sheet universal tray,
Tray 2. The trays adjust to accept various media sizes.
Tray 1
The Tray 1 Feeder feeds paper into the printer. The Feed Drive Assembly drives the Tray 1
Feed Roller to feed media from the tray. Tray 1 components include:
• Feed Roller
• Pick Clutch that engages the Feed Drive Assembly to the Feed Roller.
• No Paper Sensor that detects whether paper is in Tray 1.
5/2011
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Figure 1 Tray 1 Feeder
Principles of Operation
Xerographics, Major IOT Assemblies