IBM System/32 Introduction And Maintenance Manual page 414

33FD STEPPER MOTOR
The 33FD stepper motor is different from the
printer stepper motors in two respects:
1. The 33FD motor has only four poles and
turns 90 degrees for each step.
2. The 33FD motor is not detented electri-
cally but is detented by the geneva mech-
anism it drives.
The motor consists of four pole windings and
a rotor that is a permanent magnet. As shown
in the accompanying diagrams, two access lines
must be active to energize one phase line.
The first illustration
II
shows the motor in the
phase 3 position. By energizing the track 0 line,
the rotor rotates
90
degrees and aligns with the
phase
0
pole
a.
Then, by energizing the
track
1
line, the rotor again rotates
90
degrees
and aligns with the phase 1 pole
Ii .
The
phase windings are energized for a minimum
of
50
ms.
Access 3/0
- , Track 0
~
Access 0/1
}=§-Track 1
Access 1/2
A Track 2
Access 2/3
Track 3
JA
+24 Vdc
>-r-----
.......
3
a
Ac ess 3/0 c
Access 0/1
Access 1/2
Access 2/3
iii
Access 3/0
Access 0/1
Access 1/2
0
Access 2/3
r----
"
,...
ra:>
I
B
-
r-
~
)
(
~
+24 Vdc
2
8-4
r--s!
Track 0
Track 1
G
Track 2
Track 3
~ 0
IA
)
+24 Vdc
c
)
~I-- ,.. 1 - - - - )
.....
,...,..
3
8)1
-
...
'\f--
+24 Vdc
2
~TrackO
Track 1
....I
A
I
I
-
A
Track 2
Track 3
0 ...
IA
I)
+24 Vdc
c
)....
I--
~I'o.~
- - - : - - )
3
1
181
I'" ....,
...
-
r-
(
) +24 Vdc
(
~
2