Sorvall RT/T6000D - Page 90

SORVALL®
Centrifuges
Repair
&
Replacement
7.
Centrifuges
with Serial Number
8601093
and lower
ONLY:
remove
the
nut (7)
securing
the
imbalance detector to
the imbalance detector bracket
(6).
8.
Remove
the
gyro
and disconnect
the electrical
connections to
the
motor.
Remove
the
screw
that holds the
ground
wire (ground
wire remains
attached
to
base).
9.
Remove
the
nut
(19).
metal washers
(20). spring
(21),
and
nylon
washers
(22) from
the
three
motor mounting
studs (18).
10.
Remove
the
motor,
with
mounting plate
attached,
from the
centrifuge.
11. Remove
and discard
the drive
belt
(9)
located under
the drive
plate.
c.
Armature Removal
1.
Scribe
a
mark on
the end
bell
(13)
and the
motor mounting plate
(11)
to
ensure
proper
orientation
during
reassembly,
then
remove
the
three
screws
and mount¬
ing plate.
2.
Remove
the
drive
pulley
(10) from
the
armature
shaft
by
loosening
the
two set
screws.
Use
a
propane
torch to
heat
the
drive
pulley
on
the
armature
shaft
to
loosen
the
Loctlte®
adhesive,
if
necessary.
Discard the
pulley.
3.
Remove
the
screw
and
washers
from the
optical
disc (15)
on
the
armature
shaft,
then
remove
the
disc.
4.
Remove
the
mounting screw
from
the
Optical
P.
C.
Board
assembly
(16),
and
remove
the
board from
the
motor
housing.
5.
Remove
both
motor brushes (17).
6.
Make
a
scribe mark
on
the end
bell
(13) and
the
motor
housing
(14)
to ensure
proper
alignment during reassembly.
7.
Remove
the
four
screws
from
the
end
bell
(13) and
lift
the
end
bell
off.
8.
Pull
the
armature (25)
from
the
motor
housing,
noting
the
positions of the
spacer
(24).
shim (26) and
spring
washer (27).
d.
Assembly Procedure
1.
Place
the
new armature
with
bearings (Cat.
No.
67830)
into
the
motor
housing
with
spacer,
shims,
and
spring
washer
in their
correct
sequence.
The
tabs
of
the
spring
washer
should bend toward
the
armature.
2.
Position
the
end
bell. aligning
the scribe
mark
with
the
one on
the
motor
housing,
then
Install and tighten
the
four mounting
screws.
3.
Reinstall the
motor brushes.
If
the
brushes
are worn
to
less
than
6
mm
(1/4
inch),
replace
them
with
a new
pair.
5-47