Controlling The Belt Motor - Oce 3121 Technical & Service Manual

17 Controlling the belt motor

Outline
Block diagram of the control circuit for the belt motor.
The belt motor is a DC motor.
The microprocessor (Q1) on the RDF control PCB sends the following signals
to the drive circuit:
- the belt motor drive signal (BMON)
- the belt motor rotation direction signal (BDIR)
- the belt motor rotation speed control signal (BMPWM).
When the belt motor (M3) rotates, the clock sensor (S10) sends the belt motor
clock signal (BMCLK) to the microprocessor (Q1). In response, the micro-
processor (Q1) compares the belt motor clock signal (BMCLK) against the
pre-set rotation speed, and varies the level of the belt motor rotation speed con-
trol signal (PMPWM), The speed of the belt motor (M3) is fixed at a specific
level at all times.
Q1
CPU
560 TSM Océ 3121
RDF control PBA
BMON
Drive
BDIR
circuit
BMPWM
BMCLK
Belt
S10
Clock sensor
Functional description