Canon NP6218, FY8-13EX-000 service manual Main Motor Control Circuit, Mechanism

CHAPTER 2 BASIC OPERATION

D. Main Motor Control Circuit

1. Outline

Figure 2-104 shows the circuit used to control the main motor (M1); the circuit has the following functions:

qturns on and off the main motor.

wcontrols the main motor to a specific rotation speed.

The main motor (M1) is a DC motor that has a built-in clock pulse generator. When the motor rotates, it generates clock pulse signals (MMCLK*) according to the revolution of the motor. The speed control circuit matches the phases of the frequency of these clock pulses and that of the reference signals to control the main motor (M1) to a specific revolution speed.

2. Mechanism

When the main motor drive signal (MMD) from the DC controller circuit goes ‘1’, the drive circuit of the motor driver turns on, thereby rotating the main motor (M1) at a constant speed.

While the main motor is rotating at a specific speed, the motor driver PCB keeps sending the specific speed state signal=0 (MLOCK*) to the DC controller PCB. If, for some reason, an irregularity occurs in the rotation of the main motor, the MLOCK* signal goes ‘1’.

If the main motor drive signal (MMD) remains ‘1’ and the MLOCK*=0 remains unchanged for about 1 sec, the DC controller identifies a main motor error and stops the main motor and, at the same time, indicates ‘E010’.

J 206 +34V J 501
		- 1
		- 2
J 303		J 502
- 3	MMD	- 2
DC controller			Clock pulse generator
			Drive circuit
PCB
J 303		J 502	Drive
- 4	MLOCK*	- 1	current
			M1
			Phase control
			circuit
			Main motor
			Hall IC output
			MMCLK
			Reference signal
			Main motor driver PCB
			Figure 2-104

2-4 COPYRIGHT © 1997 CANON INC. CANON NP6218 REV. 0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)