FRIDEN STW - Page 8

Peas
8
FRIDEN
CALCULATING
MACHINE
CQ., INC.
B15-50
MODEL
STW
SELECTING LEVER
NOKE
SELECTING
GEARY
B.
SELECTION
~
MAIN
KEY
BOARD:
Study
the
above
illustration
with
a
machine
uncovered.
Depress
the
number
6
Numeral
Key;
watch
the
action
which
takes
piace
as
the
Key
is
traveling
downward.
Note
the
Key
Lockbar
slip
into
the
notch
in
the
Keystem.
The
Lockbar
is
out
of
sight
inside
the
Keybox,
but
its
movement
can
be
seen
at
the
front
end
of
the
Keyhox.
Note
the
movement
of
the
Selecting
Bar
as
it
moves
to~
ward
the
front
of
the
machine
and
pulls
the
Se~
lecting
Gear
along
with
it.
- NOS SEGMENT
po -NO. 7 SEGMENT
“ONO. 8 SEGMENT
“NO. 9 SEGMENT
C.
You
will
see
that
this
action
has
placed
the
Selecting
Gear
in
line
with
the
Number
6
Seg-
ment
on
the
Actuator.
Now,
if
the
Plus
Bar
is
depressed
and
the
machine
operated,
a6
will
appear
in
the
Upper
or
Accumulator
Dial
di-
rectly
inline
with
the
Numeral
6
Key
in
the
Main
Key
Board.
Release
the
6
in
the
Main
Key
Board
with
the
Zero
Key
at
the
bottom
of
the
column
in
which
the
6
is
located.
Note
how
the
Zero
Key
moves
the
Key
Lockbar
rearward
to
release
the
Numer
-
al
Key
and
the
action
of
the
Spring
under
the
6
Key
lifts
it
upward
to
restore
it
to
its
normally
clear
position,
Repeat
the
above
operations
on
other
Numeral
Keya;
note
that
a5
or
a
9
Key
moves
the
Selecting
Bar
a
greater
distance
than
a
lor
&
Key.
See
the
reason
for
this
in
the
ar-
rangement
of
the
Segments
on
the
Actuators.
CARRIAGE:
The
movable
Carriage
on
the
Friden
Calculating
Machine
gives
us
a
means
of
chang-
ing
the
value
of
any
number
or
figure
placed
in
the
Main
Key
Board
by
simply
shifting
the
Car~
HOW
THE
MACHINE
WORKS
riage
to
the
right
or
leit,
depending
on
whether
it
is
desired
to
increase
or
decrease
the
value
of
the
Key
Board
Factor.
Thus,
with
the
figure
1
in
the
first
column
of
the
Main
Key
Board
and
the
Carriage
in
the
first
position
or
extreme
left,
the
figure
]
is
then
in
the
UNITS
place
and
has
the
value
of
1,
Shift
the
Carriage
one
place
to
the
right
and
the
|
is
then
in
the
TENS
place
and
has
the
value
of
10;
third
Carriage
position,
100,
etc.
Thus,
the
value
of
the
Key
Board
Factor
is
INCREASED
by
shifting
the
Carriage
to
the
RIGHT
and
would
naturally
be
DECREASED
by
shifting
the
Carriage
to
the
LEFT.
BASIC
OPERATIONS:
ADDITIONand
SUBTRAG-
TION
ere
the
two
main
Basic
Operations
of
any
computing
machine.
All
the
‘‘ Useful
Answers'’
used
in
mechanical
calculation
are
obtained
-by
pne
or
a
combination
of
both
of
these
basic
func
-
tions
of
arithmetic.
Thus,
multiplication
becomes
a
process
ef
ADDING
a
number
(the
multiplicand)
te
iteelf
a
given
number
of
times
(the
multiplier)
to
obtain
a
result
(the
product},
Division
is
a
process
of
SUBTRACTING
a
given
number
(the
divisor)
from
another
number
(the
dividend)
a
number
of
times
to
obtaina
result
(the
quatient);
and
sometimes
part
of
the
dividend
is
left
over
and
this
is
called
the
remainder,
Thus,
you
see
that
all
arithmetical
processes
make
use
of
one
ar
both
of
these
Basic
Operations,
ADD-SUBT. GEAR~
TO
SUBTRACT
To
ADD
—~ADO~SUBT. GATE:
D.
ACCUMULATION:
Accumulation
of
numbers
in
calculations
is
the
adding
of
one
number
to
an-
other
or
adding
a
series
of
numbers
together.
This
accumulation
gives
us
a
total
which
is
de-
sired
when
it
is
necessary
to
determine
the
amount
occasioned
when
two
or
more
numbers
are
added
together;
thus,
the
accumulation
of
Z
and
2
becomes
4,
etc.
In
the
Friden
Calculating
Machine,
this
process
of
accumulation
is
performed
mechanically
by
the
medium
of
gears
and
dials.
As
a
demonstra-