sharp cd c4400 Service Manual
Inthe interests of user-safety the set should be restored to its original
condition and only parts identical to those specified be used.
Page
1. BASIC CONSTRUCTION 2, 3
2. RELATION OF THE MECHANICAL OPERATION OF THE MAIN GEAR AND THE TRAY
AND THE ELECTRIC CONTROL 4
3. TIMING CHART FOR TRAY MOVEMENT
5,6
4. TIMING CHART OF ELECTRIC SIGNALS FOR TRAY MOVEMENT 7
5. THE TURNTABLE MOVEMENT IS EXPLAINED AS FOLLOWS 8-10
6. SUPPLEMENT 11
Service Headquarters: Sharp Plaza,
Mahwah, New Jersey 07430-2135
The basic movement the CD changer is describedas follows.
See 2 and 3.
• The CD changerbasicallyconsistsofthetray(208)whichslides
on the
CD chassis (224), and the maingear (238) to movethe
tray. As the maingear rotates, the projection (Zenbea
Pi.n)
on
the main gear causes rotation of the CD up/down cam (241),
resulting in up/down of the CD mechanism and CD chucking.
The maingear is driven by Loading Motor MTR1.
Onthetray (208),theturntable (209)toload a discandthe disc
select motor MTR2 to rotate the turntable are set up. MTR2
controls the turntable movements.MTR2 which rotateson the
traycanrotatethedisctableregardlessoftheopen/closemotion
of the tray.
•Thefollowingarethe electricpartswhichcontrolthemovements
to open/closethe tray and to rotatethe turntable.
Tray Driving Motor (Loading Motor) :
MTR1
Tray Open Switch to detect that the tray is completely
open:
SW1
Photo Sensor (Tray Close SW) to detect that the tray is
closed: PHi
PhotoSensor (Mecha UP SW)to detect that the CD mechanism is UP :PH2
Turntable Driving Motor (Disk Select Motor) : MTR2
Photo Sensor (Disc Select SW) to detect the disc table
position: PH3
TheTable
2 below showsthe portsofthemicrocomputer(IC801)
to decode signals and to drive with the use of the above parts.
Under the main gear to control the
screenofconcentriccircleisplaced.The relationofthe main
tray movements, a double
gear
rotatingpositionandthe tray position is 1:1. Height of the screen
can bechanged withthe trayclosed or at the maingear position
corresponding to the tray position where the CD mechanism is
movedup/down. As a result,the
LEDlight ofthe photo sensors
PH1and PH2canbe shutorpassedto changeoutput of PH1and
PH2 high and low.Thetray movementis controlledby changing
this signal.
The signals PHi and PH2 change depending on the height of
peripheralscreen, andthe inner screen, respectively.When the
screen is placed low, the LED lightis passed to makethe photo
transistor inside the sensor turn ON, resulting in low output
(approx.0.2V). Ontheotherhand,whenthe screenisplacedhigh,
the lightisshutto makethe phototransistorOFF,resultingin high
output (5V).
Summary:
MTR1
:Controls opening/closingof the tray and up/down of the
CD mechanism.
[MTR1
rotation(clockwise/counterclockwise)
tl d' tl f th . irnu aneous
R
t
~
0 a Ing irec Ion0 e main gear
~
Opening/closingof the tray
~
Up/downof CD mechanism
. wo ypes
~J
S' It
~
two
t f
tvoes S 0
MTR2 :Controls the turntable rotation.
The movementsofthe maingear and the tray,whichare
structurallycomplicated,will be explainedindependently
inthe othersection.Thereafter,the turntable movement
will be described.
PORT .-UN\.,;
Port for Macha UP SW(PH2)
Port for Tray Close SW(PH1)
Port for Tray Open SW(SW1)
Port to drive MTR1 45 pin
Port to drive MTR2
Port for Disc Changer SW(PH3)
IIVN
•
ICaDi
47 pin
48 pin
46 pin
42 pin
41 pin
43 pin
OPEN
}J.-COM
IC801
44 pin
OF MICROCOMPUTER
2
SW1
Tray close
photo sensor
NAME
MECHA
CLOSESW
OPENSW
CLOSE MTR
OPEN MTR
MTR+
MTRDISCTBLSW
Loading motor
(MTR1)
CIRCUIT DIAGRAM
UPSW
-2-
Discselect motor
(MTR2)
Disc changer
photosensor
2
253
f-S09
-3-
613 x2
3
In case the main gear rotates once clockwise while the CD
mechanism is not chucking a disc andthe tray isopen, a series of
movements are performed as follows:
The open tray is closed. Complete closing is followed by UP
movement of the CD mechanism (disc chucking movement).
When the main gear continuesrotation, a series of movementsto
open the tray is conducted again.
These movements are equivalent to the following actual use
condition; when the tray isopen, a disc is loaded on the turntable.
Then the tray is closed to play CD. In this play mode the tray is
opened.
'The reverse movements are performed by rotating the main
counterclockwise;
when
the main
gear
is rotated
gear
once
counterclockwisewhile the CD mechanism is chucking adisc and
the tray is open, the tray is closed. The DOWN movement of the
CD mechanism and then the tray open movement follows. The
movement to open/close the tray, which does not simply correspond to the rotating direction of the main gear, will change
according to the CD movement mode.
The Table 3 below shows the above-mentioned movement. The
CD stop condition is main in the actual use of the CD changer.
Figure 5-1to 5-6 and 6-1 to 6-6 shows a series ofprocess to close
the opening tray with the CD mechanism down, and Fig. 7, the
Timing Chart of Electric Signals.
The main gear to slide the tray is of rack' pinions.
Double pinion gearsof the main gear are set vertically. Their
diameters are slightly different. One gear with larger diameter
engages withthe rack gear onthe left sideofthetray;the otherone
with smaller diameter engages with the rackgear on the rightside
of the tray.
STATE
CD stop condition (CD Mechanism UP)
NU
I A I
INU
DIRECTION OF
CLOCKWISE
The tray is opened with CD Mechanism UP.
(In case the tray is opened in the CD mentioned left, the main gear is rotated
PLAY mode)
The tray is closed with CD Mechanism Down.
(In case the tray is opened by stopping CD.)
Movementdirection
To close the tray under the condition as
counterclockwise.
COUNTERCLOCKWISE
To close the tray under the condition as
mentioned left, the main gear is rotated
clockwise.
GEAR
COUNTERCLOCKWISE
CLOCKWISE
-4-
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