Brother MFC-9420CN Service Manual

Confidential
3-20
8 Drum Cleaning
Transfer belt cleaning process means that the residual toner on the transfer belt is removed.
(1) Structure of transfer unit cleaner PU (Refer to Fig.3-23.)
1) Transfer unit cleaner PU is located as shown in Fig.3-9.
2) Cleaning brush is a semiconductor type fur brush to clean the surface of transfer belt
as rotating. However, the cleaning brush stays away from the transfer belt while
imaging on the transfer belt.
3) Belt cleaning roller is positively biased by the positive voltage FCBV(V).
4) FCBV(V) is injected to the cleaning brush as well, and the cleaning brush is self-
biased by the resistance of brush.
5) Cleaning roller rotates as contacting to the belt cleaning brush.
(2) Process of transfer belt cleaning (Refer to Fig.3-23.)
1) There is the residual toner on the surface of transfer belt after the paper transfer
process.
2) Cleaning brush is positively self-biased. Cleaning brush has the negatively charged
residual toner fall off from the surface of transfer belt, and electrically absorbs the
residual toner into the belt cleaning brush.
3) Cleaning roller has been biased to the positive FCBV(V), the residual toner absorbed
into the cleaning brush is attracted by the positive FCBV(V) is adhered to the surface
of cleaning roller.
4) Waste toner adhering to the surface of cleaning roller PU is scavenged by the
cleaning blade and collected to the waste toner pack by the waste toner feeder.
Cleaning Brush
Cleaning Roller
Waste Toner Feeder
Claening Roller PU
Drum
Residual
Toner
Transfer Belt
FCBV
Fig. 3-23

Brother MFC-9420CN Specifications

General

Print technology	Laser
Maximum resolution	1200 x 2400 DPI
Economical printing	Yes
Print speed (black, normal quality, A4/US Letter)	31 ppm
Print speed (color, normal quality, A4/US Letter)	8 ppm
Digital sender	No
Number of print cartridges	4
Scanner type	Flatbed scanner
Scanner features	Scan to: e-mail, image, OCR, file
Copier resize	25 - 400 %
Maximum copy resolution	600 x 600 DPI
Maximum number of copies	99 copies
Copy speed (black, normal quality, A4)	31 cpm
Copy speed (color, normal quality, A4)	8 cpm
Faxing	Color faxing
Fax memory	500 pages
Modem speed	33.6 Kbit/s
Fax speed dialing (max numbers)	200
Total input capacity	750 sheets
Maximum input capacity	250 sheets
Auto document feeder (ADF) input capacity	35 sheets
Maximum internal memory	576 MB
Bundled software	ScanSoft PaperPort Presto! PageManager
I/O ports	IEEE-1284 USB 2.0
Dimensions (WxDxH)	483.5 x 514 x 530 mm
Printer management	BRAdmin Professional, MIB-II
Networking features	10Base-T/100Base-TX
All-in-one functions	Fax, Scan
Color all-in-one functions	copy, fax, print, scan
Compatible operating systems	Windows 98(SE)/ Me/ NT WorkStation 4.0/ 2000 Professional/ XP Mac OS 9.1 - 9.2, Mac OS X 10.2.4+
Sustainability certificates	ENERGY STAR
Power consumption (standby)	85 W
Power consumption (PowerSave)	16 W
Power consumption (average operating)	1090 W
Operating temperature (T-T)	10 - 32 °C
Operating relative humidity (H-H)	20 - 80 %
Market positioning	Business