Sony UP-860 Service Manual page 50

5-5. MOTOR DRIVE SECTION (1C201)
The platen motor, Head UP/down motor, and Door motor are driven with IC201,
10202, 10203, and IC209,. They are all controlled by IC301.
5-5-1. Platen motor
The platen motor speed is controlled by 1C201(M51970L). The frequency of the FG
(optic read out) of the motor section is detected and fed back to 1C201, which
controls motor drive transistor Q205 to control the speed.
1C204 (M54544AL) can drive the motor in the forward or reverse direction.
The motor is turned ON/OFF and its speed controlled by 1C301-©,®, @,6.
(See the explanation of the system control section.)
Since this unit produces the INT-V signal that provides the screen printing timing
by dividing the FG frequency, even if there is some slight fluctuation in the FG
frequency, the paper feed distance and printing quality are held constant.
5-5-2. Head U/D motor and DOOR motor
The Head U/D motor and DOOR motor are controlled by IC202 and 203 (both
are M54543L). This IC can drive the motor in the forward or reverse direction, and
it is controlled by IC301-@),@,©,©).
Head U/D motor
1c301.@ | 10301.@
H L
goes down the head
goes up the head
locks to motor
10301-@ | 1301-8
L H Opens the door
H L Closes the door
The above motor operation is controlled by detecting the condition of Head and
Door with IC301 Pin@,@,69,@ .
Head condition Pew | rere
Top
Condition
Top position of the
head to open the door.
Head is at this position
except for |PRINT:
Head is pressed
against the platen.
Middle
Bottom
Door condition
[rea [ea
Open L H The door is opened.
Close H L The door is closed.
BF
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