Daisy Motor And; Motor Home Position Sensor - JUKI 6100 Technical Manual

Fig.
7.21
is
an
illustration
of the
hammer
unit
select
pulses
which
drive
the
hammer
and
the
check pulses
which
are
used
as a
feedback
signal
to the
MPU.
The
HMSL
line
drives
the
hammer
circuitry
with
a series
of pulses
which
correspond
to
the density of the character to
be
printed.
As
the density of the printed charac-
ter
to
be
printed.
As
the density
of the printed character increases the
number
of
pulses applied to
the
hammer
coil also increases.
Three
factors
determine
the
number
of
pulses sent
and
therefore the
amount
of impact of the
hammer.
First
is
the density of the character to be
printed.
The
control
ROM
on
the
MCU-1
board
has
look-up
tables
which
contain the
number
of pulses for
the corresponding
characters.
The
second
factor for
determining
pulse
count
is
the pitch
selection.
There
is
a separate table
in
the control
ROM
for
each of the four
possible pitches
available
(10/12/15/PS).
The
third factor
used
is
the
setting
of the impression
control switch
on
the operation
panel.
This
switch,
when
in
the
on
position,
adds
pulses to the pulse
count of the look-up
table
and
thereby increases the
impact of
the
hammer.
The
primary purpose of the impression control switch
is
to
com-
pensate
for
multi-part forms.
P2.6
HMSL
(N)-
U
U
LT^
i__r
PO.O
HMCS
n n
n
5
Hammer
application time
J~L
Fig.
7.21
Hammer
drive signal
7.3
Daisy
motor and
linear
motor
home
position sensor circuits
When
the
power
switch
is
turned
on or the printer
is
initialized,
the detector
cir-
circuits
operate as follows:
7.3.1
The SP
home
position sensor circuit
detects
the
home
position of
the
printing
head
at
the
left.
Fig.
7.22
SP
home
position sensor
circuit
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61
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