2-2. FAX240 (with Shuttle Cutter and Decurler)
2-2-1. Decurler
The decurler unit consists of the decurler
cover, decurler bracket and the decurler
spring on the platen roller shaft.
In standby mode, the decurler bracket is
down at the standby position. When the ma-
chine starts printing, the decurler spring on
the platen roller shaft lifts up the decurler to-
wards the bend in the decurler cover. Then
the paper path is curved as shown in the bot-
tom diagram, so that the two bends on the
decurler cover can apply negative stress to
the curled paper to get rid of the curl from the
paper.
The decurler bracket always applies the same
negative force (N) to the paper, but the nega-
tive stress on the paper varies depending on
the amount of paper remaining. The tension
(T1) when the roll is almost full is stronger
than the tension (T1’) when the roll is almost
empty, and the tension (T2) equals to (T2’).
So, the paper path is curved more strongly as
the paper roll gets lighter.
After printing has finished, the machine cuts
the paper then reverses the Rx motor to feed
back the paper to the printing position and to
move the decurler bracket down to the
standby position.
2-2-2. Shuttle Cutter
The shuttle cutter consists of a paper guide frame, rotary cutter blade, motor, cutting start sensor (SB-7), cutting
end sensor (SB-8), and jam sensor (SB-5).
In standby mode, the cutter blade is always at the cutting start position. When the machine has finished printing,
the Rx motor stops then the cutter blade shuttles across the paper. The cutting end sensor detects that the cutter
blade has finished cutting, then the CPU reverses the cutter motor to move the cutter blade to the cutting start posi-
tion. After cutting, the Rx motor feeds out the copy, then it reverses to feed the paper back to the printing position
and to move the decurler bracket down to the standby position.
T1 > T1’
T2 = T2’
N = N
Paper Roll
Thermal Head
Decurler Cover
Decurler Bracket
Platen Roller
T1
T2
N
Paper Roll
Thermal Head
Decurler Cover
Decurler Bracket
Platen Roller
T1’
T2’
N
Motor
Tension spring
Cutter end sensor (SB-8)
Cutter start sensor (SB-7)
Rotary cutter blade
Paper jam sensor (SB-5)
Cutter drive wire
D-4
