Stearns 87,000 Series Operating instructions

Important
Please read these instructions carefully
before servicing your Stearns Brake.
Failure to comply with these instructions
could cause injury to personnel and/or
damage to property if the brake is
serviced incorrectly. For definition of
limited warranty/liability, contact Rexnord
Industries, Inc., Stearns Division, 5150 S.
International Dr., Cudahy, Wisconsin
53110, [phone].
Caution
1. Servicing shall be in compliance with
applicable local safety codes
including Occupational Safety and
Health Act (OSHA). All wiring and
electrical connections must comply
with the National Electric Code (NEC)
and local electric codes in effect.
2. To prevent an electrical hazard,
disconnect power source before
working on the brake. If power
disconnect point is out of sight, lock
disconnect in the
off position and tag
to prevent accidental application of
power.
3. Be careful when touching the exterior
of an operating brake. Allow sufficient
time for the brake to cool before
disassembly. Surface may be hot
enough to be painful or cause injury.
4. Do not operate brake with housing
removed. All moving parts should be
guarded.
5. After usage, the brake interior will
contain burnt and degraded friction
material dust. This dust must be
removed before servicing or adjusting
the brake.
DO NOT BLOW OFF DUST using an
air hose. It is important to avoid
dispersing dust into the air or inhaling
it, as this may be dangerous to your
health.
a) Wear a filtered mask or a
respirator while removing dust
from the inside of a brake.
b) Use a vacuum cleaner or a soft
brush to remove dust from the
brake. When brushing, avoid
causing the dust to become
airborne. Collect the dust in a
container, such as a bag, which
can be sealed off.
6. Maintenance shall be performed only
by qualified personnel familiar with
the construction and operation of the
brake.
7. For proper performance and
operation, only genuine Stearns parts
should be used for repairs and
replacements.
Warning! Any mechanism or load held
in position by the brake should be
secured to prevent possible injury to
personnel or damage to equipment
before any disassembly of the brake is
attempted or before the manual release
knob is operated on the brake.
Instructions
1. To remove housing, follow
instructions listed under each
individual brake series in Figure 2,
then continue with the following
steps.
2. Unscrew pressure spring screw (19)
from pressure spring tube (152).
Save spring washers (134), if
included, they may be reused in
reassembly. Remove pressure
spring (11).
3. Disconnect coil leads. Remove three
support plate mounting screws, lock
washers and support plate assembly
(126).
4. Clamp support plate assembly in a
vise. Remove fluted pivot pin (130)
using 3/8'' diameter drift. The face of
one side of pin will show marks from
insertion. This is fluted side. Drive
out from non-fluted end. Remove
lever arm (17) and spring tube (152)
as an assembly. Clamp lever arm in
a bench vise. Drive out pivot pin
(spring tube) (152P) using 1/4''
diameter drift. Discard old spring
tube (152) and pin (152P).
5. Insert new spring tube (152) into
lever arm and faster with new pivot
pin (152P).
Figure 2
Figure 1
Service Instructions for Pressure Spring Tube Kit
Series 87,000; 87,200 and 87,700 Disc Brakes
®
Brake Replacement Parts
P/N 8-078-947-04
effective 6/1/98
Item
No. Description of Parts Included in Kit Quantity per Kit
19 Pressure spring screw 1
152 Pressure spring tube 1
152P Pivot pin (spring tube) 1
87,000 Series
87,200 Series
87,700 Series
Remove manual release knob (148), two
housing nuts (15) and housing (7).
a) Remove any accessories, sprockets,
sheaves, etc., from brake shaft on
housing side.
b) Remove manual release knob (148), two
housing nuts (15), and housing (7).
a) Remove the brake and motor as a unit
from the gear reducer.
b) Remove four housing cap screws (15),
lock washers (15W).
c) Pull back on housing and shaft
assembly to remove as a unit.

Figure 3
6. Clamp support plate assembly into a
vise and insert lever arm and spring
tube assembly. Reuse fluted pivot pin
(130) to attach lever arm to support
plate assembly. [Be sure that sector
gear and pinion mesh freely and that
fluted pivot pin (130) is seated
securely.]
7. Install support plate assembly to
brake.
NOTE: Black, white, orange and purple
springs were designed to eliminate the
use of spacers, except on 6 lb-ft brakes.
8. Replace pressure spring with screw
(19) using the required number of
pressure spring washers (134) as
shown in Table above.
9. Compress pressure spring by
tightening screw (19) until it is firmly
seated. Do not overtighten, maximum
torque to be applied is 100 in-lbs
(8 ft-lbs).
10. Manually lift solenoid plunger to
maximum travel. Depress and allow
solenoid plunger to snap out several
times. Measure solenoid air gap
between mating surfaces of solenoid
frame and solenoid plunger. (On
vertically mounted brakes, it will be
necessary to push solenoid plunger
into solenoid frame to the point
where spring pressure is felt, before
measuring solenoid air gap.) The
solenoid air gap measurement
should be as factory set between
13/16'' to 15/16''.
11. The solenoid air gap may be
increased by raising or decreased by
lowering the wrap spring stop (76).
To accomplish this, loosen two (stop)
screws (76S), move wrap spring stop
slightly and retighten screws. Repeat
Step 10 after each change in wrap
spring stop position to obtain original
solenoid air gap measurement of
13/16'' to 15/16''.
12. Reconnect solenoid coil leads.
13. Replace housing, screws and manual
release knob in reverse order of the
appropriate point in Step 1.
14. Caution! Do not run motor with brake
in manual release position. It is
intended only for emergency manual
movement of the driven load, not as
a substitute for full electrical release.
NOTE: For complete instructions,
with
troubleshooting
, request sheet
applicable to the series of brake that
you have.
Copyright© 1998 by Rexnord Industries, Inc.
Rexnord Industries, Inc., Stearns Division, 15150 S. International Dr., Cudahy, WI 53110 [phone] Fax: [phone]
Nominal Static
Torque (lb-ft)
6
6
10
10
15
15
25 & 50
25 & 50
35, 75 & 105
35, 75 & 105
Color of
Spring
Black
Blue
Black
Blue
White
Yellow
Orange
Red
Purple
Green
Qty. of
Spacers
6
6
0
1
0
7
0
4
0
3