Brother HL-2700CN Series, Service Manual

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IV-3
(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.
• Sequence Control
• Laser Control
• Fusing Temperature Control
• Interface Control
<Basic Mechanism of Color Printing>
(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
(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.