Main Motor; Main Motor Drive - Toshiba e-STUDIO453 Service Manual

10.3

Main Motor

10.3.1 Main motor drive

The main motor consists of the motor and the drive board combined with the motor, and its rotation is
controlled by control signals (three) and reference frequency.
LGC board
CN3
(MAMCK)
MAMPL
MAMCW
MAMBK
MAMON
24v
10
(1) LGC board outputs the control signals for the main motor rotation. (MAMCW: Motor rotation direc-
tion setting, MAMON: Motor rotation command)
(2) The excitation phase switching section excites each phase of the main motor. → The main motor
is rotated.
(3) Hall elements A, B and C detect the rotation position of the motor (rotor).
(4) The excitation phase switching section switches the excitation of each phase.
(The motor keeps rotating by repeating from (2) to (4).)
(5) An FG pulse is generated by the FG pattern of the encoder attached to the main motor.
(6) The FG pulse and the reference frequency from the LGC board are compared in terms of the
phase and speed, and the difference is added to the IC1. The fluctuations in the power supply
voltage is also added to the value. (Signal generation)
(7) In accordance with the signal obtained in the step (6), the excitation phase switching section
changes the switching timing.
i.e. The FG pulse and reference frequency are controlled to be equal. → The main motor rotates
at a fixed speed. (Locked range)
(8) When the main motor enters the locked range, the excitation phase switching section outputs the
MAMPL signal to the LGC board. ("L" level)
(9) When the MAMBK from the LGC board becomes "L" level, the main motor is braked. When the
MAMON signal becomes "H" level, the main motor is stopped.
e-STUDIO350/352/353/450/452/453
DRIVE SYSTEM
Man motor (PC board)
Wave
Phase
correcton
comparator
Speed
comparator
Lock
protecton
crcut
24v
Voltage
detecton
Exctaton
crcut
phase Phase W
swtchng
secton
Hall element A
Rotaton
Rotor
control
poston
detecton
Fig. 10-301
10 - 2 © 2003 - 2008 TOSHIBA TEC CORPORATION All rights reserved
Man motor (Motor)
FG pulse
Phase V
Photo-
nteruptor
Phase U
Hall element C
Hall element B