Printer Theory Of Operation; System Summary - Xerox Phaser 3150 Service Manual

Summary of Product

4.2 Printer Theory of Operation

4.2.1 System Summary

The printer consists of the following main functional components:
1) The Firmware
Engine firmware controls the whole printing process.
2) The Print Engine
1.
Engine Frame
2.
Paper Feed
The paper feed system consists of a 250-sheet main paper tray (Tray 2), a multi-purpose paper tray (Tray 1),
pickup rollers, friction pads, and feed rollers. The rollers and sensors in the paper feed path control paper
registration and guide the paper through the image transfer, image development, image fusing and exit
assemblies. The paper path has an anti-static connection to ground to eliminate problems due to static charge on
the paper.
3.
Main drive mechanism
The main drive is a bi-polar, two phase motor. It drives the drum, paper pick, and paper feed rollers using a gear
train mechanism.
4.
Image development unit
Using a Laser Scanner Unit (LSU), this portion of the mechanism creates the image on the OPC drum (part of the
integrated toner cartridge).
5.
Image transfer unit
This unit uses the high voltages supplied by the HVPS to move the image from the OPC drum onto the paper.
6.
Image fusing unit
This unit permanently fixes the toner image onto the paper. This is achieved using a temperature controlled
heating unit (the fuser).
7.
Electronic boards include:
a.
The Main control board, consisting of:
Main processor asic (166 MHz SPGPm)
Memory (Flash ROM containing the control program and DRAM for working memory)
Engine interface parts (motor control, fuser control, HVPS control, and sensors)
PC Interface (USB , Parallel, Network)
Bus, DMA and I/O handling
b. Control panel
c.
PC Interface
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