Canon C12-8453, Руководство по обслуживанию

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(2) Silent film transport
The following measures have been taken for a silent film transport.
1) Coreless motor for M1
The M1 motor runs smoothly with little vibration and noise (especially at high
frequencies). The coreless motor is quieter than ever.
2) Timing belt for the first gear and film rewind transmission
The film transport and rewind noise (M1 motor noise) is reduced with vibration-
resistant rubber.
3) Floating support incorporating rubber bushings for the film transport unit
The camera's vibration noise caused by the film transport unit is reduced with
the use of vibration-resistant rubber.
4) PWM (pulse-width modulation) control for a quieter low-speed control with the
low-speed film rewind motor.
5) Drive transmission switchover with the M2 motor
In the operation sequence, the M1 motor does not execute the driving
transmission switchover. This eliminates one source of noise.
6) Reduced sound pressure at the audible level
The length of time that driving noise is generated by each internal mechanism
has been shortened to reduce the sound pressure at the audible level.
7) Reflex mirror up-movement shock absorption
A high-density material is now used for the mirror stopper (molt plane). The 3mm
thickness is also thicker than the 1mm thickness of the mirror stopper in
previous cameras. It reduces the noise generated when the mirror goes up.
Part 2: Technical Information
2-13
Fig. 2-17 Film Transport Mechanism
Rubber bushing X 2
(Prevents inclination)
Rubber bushing X 3
Rewind belt
Fork
Planetary gear Low
Control lever Low
Solar gear
Planetary gear High
Control lever High
Cam contact
Planetary arm High
Pulley
M1
Spool gear
First gear belt
Planetary arm Low
M1
M2
Flash driver
transmission system