Brother HL-3450CN Series, Service Manual

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HL-3450CN SERVICE MANUAL
4-5
(5) Control System
The control system consists of the following 4 (four) control parts and runs the printer
by processing the interface signals transmitted from the Host computer and interfacing
to the print, transfer, scanning and transport systems.
x
Sequence Control
x
Laser Control
x
Fusing Temperature Control
x
Interface Control
1.2 Basic Mechanism of Color Printing
1.2.1 Principle of color printing
Color printing is made through the subtractive process by combining the three primary colors,
yellow, magenta, and cyan. Fig.4-2 shows the three primary colors and subtractive process:
C
B
K
G
M
R
Y
Y: Yellow
M: Magenta
C: Cyan
R: Red
G: Green
B: Blue
K: Black
Fig. 4-2
1.2.2 Basic color printing process
(a) The printer has a toner cartridge of each color yellow, magenta, cyan and black as
shown in Fig.4-3.
(b) The toner image developed using the primary colors is transferred to the transfer drum
for the printed color combination as shown in Fig.4-4 a .
(c) The toner image formed on the transfer drum is transferred to the transported paper as
shown in Fig.4-4 b .
(d) The toner on the paper is fused by the thermal fixing unit to fix the toner image onto
the paper as shown in Fig.4-4 c .
Summarizing the above processes, a toner color layer is formed on the transported paper,
and subsequently, the color image is made through the subtractive process.