Sansui FR-4060 - 2. OPERATION OF MECHANISM; 2-1. Operation of Auto Mechanism

2.
OPERATION
OF
MECHANISM
2-1. Operation of Auto Mechanism (See Fig. 2-1)
1.
At the condition of STOP, the micro switch (SW1)
and start switch (leaf switch) are OFF, on the other
hand, the micro switch (SW2) and muting switch
are ON. (cartridge at shortcircuiting condition).
When the cuing lever is placed at START position,
start switch becomes ON and timing motor starts
running.
The timing motor is coupled with starting cam and
the starting cam controls the micro switch. When
the timing motor starts running, the starting cam
starts moving together and the micro switch (SW1)
becomes ON from OFF. (Therefore, as for the start
switch, the switch is turned ON temporarily).
Simultaneously with it, the main motor will start
operating.
When the starting cam makes in half revolution,
the starting plate will turn up to a certain angle.
Meanwhile, if the cam does in another half revolu-
tion, the plate will reversely revolves in its function.
Namely, when the starting cam carrys out in one
revolution, the starting plate makes one cycle move-
ment.
As tne starting plate and starting cam are coupled
with crank lever, the starting plate will be operated
while the timing motor is being operated. When the
timing motor, starting cam and starting plate are
operated, the return lever (1) will push PU plate ass’y
located at the lower part of the tonearm and it will
keep pushing the tonearm until it reaches to the
position of the lead-in groove of disk.
When it comes to this position, the selector plate
ass‘y. connected with tip end of selector plate
will serve as stopper and the return lever (1) which
pushes PU plate ass’y so far will be tunned over
and it does not push the PU plate ass’y anymore.
Then, it is at AUTO-IN position.
In addition, before the return lever (1) starts pushing
the tonearm, the return lever (2) is turned over
reversely by the position detector lever in order that
AUTO-IN funtion will be normally operative.
When the tonearm comes to the AUTO-IN position,
the starting cam will be made in half revolution.
The micro switch (SW2) which is so far ON will be
turned OFF, and the timing motor will stop. Simul-
‘taneously with it, the muting switch is turned OFF
(cartridge at open condition) from ON (cartridge at
shortcircuiting condition),and performance starts as
a result.
In performance, the micro switch (SW1) is ON, the
micro Switch(SW2) and muting switch are OFF. When
performance proceeds and the tonearm traces up to
the lead-out groove, the magnet located at tip end
of PU plate ass’y comes at side of reed switch and
turns this reed switch ON. When the reed swich is
turned ON, the timing motor will start running and
the micro switch (SW2) will be turned ON.
7. When the timing motor starts operation once again,
the starting cam will start next half revolution.
Then, the starting plate revolves contrary to that at
the
time
of
AUTO-IN
and
the
return
lever
(2)
pushes
the PU plate ass’y from the reverse direction and
makes tonearm return. The tonearm returned by the
return lever(2) comes to the position of arm rest, and
it will be stopped by the arm rest, then the tonearm
will land on the rest.
In the process of this return operation, the return
lever(2) turned over by the position detector lever
will return to the original condition again.
8.
When
the
cuing
lever
is
placed
at
position
of
RE-
PEAT,
the
timing
motor
starts
running
again
because
the
start
switch
is
ON
even
if
performance
finished
and
the
micro
switch
(SW1)
becomes
OFF.
Ac-
cordingly,
as
the
micro
switch
(SW1)
which
was
OFF
is
turned
ON,
REPEAT
performance
will
be
made.