Linear Encoder; Outline; Structure; Output Signal - Canon BJ-W7000 Service Manual

C. Linear Encoder
1. Outline
This printer is equipped with a linear encoder for checking the operating status of the carriage and aligning
the position of ink discharging on the media.
2. Structure
Figure 2-203 shows the configuration of the linear encoder.
Carriage PCB
CHA/CHB
Memory wire MR sensor
Figure 2-203
@) Memory wire
This is a magnetic wire on which a magnetized pattern is printed at 1/360" intervals.
@ MR sensor
This sensor reads the magnetized pattern on the memory wire, and outputs a 2-phase rectangular
wave.
3. Output Signal
The two rectangular waves (LHA, LHB) having a phase difference of 90° as shown in Figure 2-204 are
output to the gate arrays on the engine controller PCB from the MR sensor via the carriage PCB.
Carriage PCB Engine controller PCB
wat 45V
3 i 405 J206
CHA 2 - 35° LHA 35
MR sensor | CHB
4 es
-36
LHB -36
Gate array
A
]
ahr
Gate elec. nw. | call eS LeDe
reel)
2
ee
feel
ab ea AS-i
Figure 2-204