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Following
description
refer to Figs 3 and 4. The
description
is so worked
out that
it covers
both
the old and the new version.
Comments
within
brackets
concern
the old version.
If PR is high a punching
cycle is started
by set-
ting PI high. After
a delay of about
10us the in-
put circuits
accepts
PI and generates
a start
trig
pulse
to the timing
circuits.
The cycle is now
started
and
can
not
be stopped.
The timing
circuits
generates
the timing
sequence
Paces
eder IE?
During TS (PI to PR), the data input gates are
open
to the buffer
register
in which
the data
is to be stored
until
punching
shall
commence.
At
the trailing
edge of TS, when
PI goes
high,
TF is
generated
and the stepper
motor
counter
is also
triggered.
(The counter
steps
forward
or backward
depending
upon
SD.)
During TF, current
is supplied
to ghe stepper
motor
which
turns
the motor
shaft
120°
to its next
position,
At the same
time
(TF +
TP delayed)
PR is set
low indicating
feeding
and
punching
continuing.
When TF has elapsed
TP and SL
TP) are
generated.
TP opens
the amplifiers
for
the punching
solenoids,
which
punch holes
according
to the buffer
register
content.
During
TP the
stepper motor
still
receives
current
for keeping
the tape steady during
punching.When
TF vanishes,
SL takes
over
and continues
to keep PR low.
The
time
during which
SL is high thus
determines
when
PR shall
go high signalling
ready
for next
cycle.
At manual
control
using any of the MF pushbuttons
TF, FH or CH, the punching-/feeding
cycle paral-
lely starts
with
PI and is completed
as described
above.
When any of the MF push buttons
is depressed
PR is low and PI and the data
inputgates
are
blocked.
4.2.2
Block diagram
- mechanical
description
See subfig.
B in Fig. 3. For each step pulse (L10,
L11,L12)
from the stepper
motor
drive
circuits,
the motor shaft (a) turns 120°, The shaft motion
is transferred to the capstan
(b) via pinwheel
(c
and slotted
wheel
(d). When the capstan
turns
(half a revolution
for each motorshaft
revolu-
tion),
the tape is fed by capstan
(b) and the
pinch roller
(e).
4.2.2.2
Punching
See subfig.
A in Fig.3.
The motor
first
advances
the tape one row
(one step,
L1O-L12)
then the
selected punch solenoid/s
receive a punch signal
wherewith the actuator/s (a) turns.
The motion is
transferred
via the punch
pin driver/s
(b) to the
punch pin/s (c)
which
is/are pressed
through
the
tape.
When the pulse vanishes
the components
re-
turn
to their
initial
positions.
See subfig.
C and D in Fig 3. If the tape is unwound
too rapidly,
the surge takeup arm
(a) moves
in the
direction
shown
by the big
arrow
in subfig.
C. The
brake
shoe
(b) (subfig.
D) then
is moved
by means
of link
(c) wherewith
it is
pressed
against
the
supply
flange
(b) (subfig.
C). The braking
conti-
nues
until
the surge takeup arm
(a)
re- assumes
its
normal
operating
position.
The tape spirals
once
around
tape lifter
(c) in sub-
fig.
C and proceeds
to the take
up flange
(d). The
take up flange is driven
by winding motor
(M1) which
presses
against
a rubber
ring at the periphery of
the flange.
_lape_checks
See subfig.
D in Fig. 3. Tape unwinding
is checked
automatically when three situations
arise:
min 200 us
lapprox 10 us
ty
delayed
PR
mox 13.3ms
TF +
TP
—-—w
Yy
GLO.
Et te
Motor
shaft
motion
Punch
pin
motion
FIG 4
A.
Tape ruptured
B.
Tape too tight
C.
Tape low
(supply almost
exhausted)
Situations
A and B are handled
by permanent
magnet
(d). This magnet
actuates
reed
switch
(S8) when
the
surge takeup
arm
(a)
leaves
the working
sector. S8
opens
and
inhibits
one
of the
conditions
for punching.
PR is set low and the ERROR
lamp on the control
panel lights.
Tape low
is sensed
by tape low sensor
arm
(e) which
rests
against
the tape on the supply reel.
As the
tape is unwound
the permanent
magnet
(f) moves
gradu-
ally toward
reed switch
S9. At a certain
point the
switch
closes wherewith the TAPE LOW lamp lights on
the control
panel.
The tape low indication
con be
adjusted
from 1000 to 10 000 rows
before end of tape
using screw
(g).
4.3
ELECTRONIC
DESCRIPTION
The punching
cycle comprises
two phases:
feed and
recording.
See Fig. 4. Feed takes
place during time
TF (approx 10. 5ns); recording
takes
place during ti-
me TP (approx 1.85ms).
Power
is supplied
to the
stepper motor during the entire
punching cycle TF +
TP. The motor thus keeps the tape stationary while
it is punched,
200us after the data is entered
into
the buffer
register,
signal
PR goes
low and remains
low until
the character
has been punched.
Signal
PI triggers
FF-TF via gate V42 (see appendix
2). IC201/11
goes high simultaneously,
and as a re-
sult
a trigger
pulse can
proceed
to counter
flip-
flops FF-Cl
and FF-C2,
The TF signal
is differentia-
ted and triggers
the counter
flip-flops
via ICé6.
When the PI signal vanishes,
the inputs to the coun-
ter flip-flops
are blocked,
thus eliminating
the
effects of any unwanted
pulses.
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