Carriage Structure - Canon BJC-1000 Service Manual

Part 4: Technical Reference

3.4.2 Carriage structure

1) BJ cartridge mounting section
The cartridge holder moves with the locking lever which secures the BJ cartridge
onto the carriage.
When a BJ cartridge is secured onto the carriage, the ribbon cable's signal contacts
are pressed against the bubble jet head's signal contacts, enabling signals to be
transmitted from the logic board.
2) Carriage driver
The stepping-type carriage motor drives the carriage horizontally across the paper by
the carriage belt. After the photo interrupter type home position sensor behind the
carriage detects the home position edge as the initial position, the carriage is
controlled by the stepping pulse sent to the carriage motor.
The carriage motor is driven by a one to two-phase exciter at a fixed current.
Also, if a vertically-oriented line, etc., is printed from both carriage directions, it will
appear to be crooked or misaligned due to mechanical reasons. However, if the
vertically-oriented line is disjointed or not continuous, any misalignment will not be
that noticeable and printing is executed from both carriage directions. The slightly-
off timing of the detected home position edge is automatically corrected with the
software.
3) Paper thickness setting
When envelopes or thick paper are fed for printing, they will rub against the head
face causing possible damage and paper contamination. This can be prevented by
using the proper paper thickness setting.
The gap between the head and paper must be set to the optimum setting (one of two
settings) to match the thickness of paper being fed. This gap is adjusted by
changing the angle of the carriage guide frame and the carriage attachment angle.
The gap between the platen and head thereby changes.
Envelope Position
Plain Paper Position
Figure 4-19 Paper Thickness Adjustment
4-20
BJC-1000
Left
Right