Brother FAX 750, Service Manual

Page: 18 / 218

III
- 5
2.3 Power Transmission Mechanism
The equipment has a single drive motor whose power transmission route can be switched by the
planetary gear systems and the solenoid. This switching allows the equipment to function in four
operation modes (scanning, paper feeding/ejecting, recording, and copying modes). For the details
about the planetary gear systems, refer to Subsection 2.3.2.
2.3.1 Structure of the gear train
All of the motor and gears are located at the left side of the equipment. As illustrated in the figure
below (On the outer side of the drive unit), the rotational torque of the motor on the drive unit is
transmitted via the gears on the drive unit to the gears on the main frame, to those on the control
panel ASSY, and to those on the platen frame.
If gear 39/62 of the friction torque transmission ASSY ("V" in the figure below) rotates, gear 20 ("z")
on the inner side of the drive unit also rotates. The rotational torque is further transmitted to the
ribbon drive gear ("w") which drives the ribbon take-up gear ("a") on the ribbon cartridge, as shown
in the figure below (On the inner side of the drive unit).
On the outer side of the drive unit and on the left sides of the platen frame,
main frame and control panel ASSY
On the inner side of the drive unit
Gear Train