Driving Of The Drive Motor; Current Route While The Motor Is Turned On/Off - Toshiba 1550 Service Manual

13.6.2

Driving of the drive motor

The drive motor M10 (PFU-MOT) is driven by transistor Q1 as described below:
When the signal MOT-ON2*
is turned on, causing current to flow from +24VfQ1's emitterfQ1's collectorfR3fDG. This will cause
the drive motor M10 (PFU-MOT) to rotate. When the MOT-ON2 signal becomes "H", Q1 is turned off,
shutting off the above current route. But while the motor continues to rotate due to its inertia, current also
tries to continue to flow, causing a voltage to be generated between the input and output terminals of the
motor. Since this voltage is applied between the anode and cathode of D1, the inverse electromotive
voltage occurring in the motor is short-circuited and restricted.
+24V
R1
Q1
R3
M10 D1
DG
Current route while the motor is turned on
*1: The MOT-ON2 signal is to cause the motor (PFU-MOT) M10 to rotate and is supplied by the copier.
When this signal becomes "L", the motor starts rotating.
Mar. 1998 © TOSHIBA
1 from the copier becomes "L", an "L" voltage is applied to the base of Q1, Q1
"L"
MOT-ON2
R2
IC1
+24V
Q1
R3
M10 D1
DG
Current route while the motor is turned off
13 - 21
R1
R2
IC1
1550/1560 OPTIONAL
"H"
MOT-ON2