Carriage Move Mechanism - Epson GT-7000 Service Manual

EPSON GT-7000

2.1.2 Carriage Move Mechanism

Scanning image is performed in the main scan direction(=1 line) by the
CCD sensor and in the sub-scan direction(=several lines)combined with
carriage unit movement. (See figure2-3)
Line type, color CCD sensor can scan 1 line in main scan
direction(parallel to the carriage unit) by one time. When scanning next
lines after the second line in sub-scan direction, CR driving moves the
carriage unit, which has CCD sensor inside, and scan the other lines.
The scanned data is sent to the control board. The scanned data for "n"
lines and "n-1" line are processed consecutively.
1 p i x e l
D o c u m e n t
M a i n S c a n
D i r e c t i o n
S u b - s c a n D i r e c t i o n b y C R M o v e m e n t
Figure 2-3. Carriage Movement
Rev. A
S e c o n d L i n e
F i r s t L i n e
S c a n n e r H e a d
( C a r r i a g e )
Carriage Unit slides into sub-scan direction along with the guide rail. For
this sliding operation, the carriage motor drives the timing belt attached
to the carriage unit by conveying the driving force through the driven
pulley and reduction gear. Scanning start position is determined by CR
HP sensor, which is located on the control board. Since the stepping
motor is used for CR motor, carriage head position is controlled under
the open loop system. (See figure2-4)
R e a r
C a r r i a g e U n i t
F r o n t
D r i v e n P u l l e y
Figure 2-4. Carriage Operation
Chapter 2 Operating Principles
C R M o t o r
C R H P S e n s o r
R e d u c t i o n G e a r
D r i v e n P u l l e y
T i m i n g B e l t
15