Dings Dynamics Group 90 Series End Mount - 450 lb-ft NEMA 4 - Manual (Page 4)

WEAR ADJUSTMENT
(Refer to Figure 3)
NOTE: Do not remove operator assembly from brake, unless
motor load is blocked. Removal of operator or blocking of
operator arm, results in loss of all braking torque.
As the friction discs wear, the air gap increases. When the air gap
reaches .090 maximum adjustment for wear is required.
1. Loosen jam nuts (15).
2. Tighten locknuts (16) until air gap at magnet is equal to the nominal
air gap listed in Figure 3. Check all four magnets.
3.
Tighten jam nuts evenly against magnet plate.
4. Adjust for magnet noise as outlined under INSTALLATION (Magnet
Adjustment).
FRICTION DISC REPLACEMENT
(See Figures 3 & 5)
NOTE: Do not remove operator assembly from brake, unless
motor load is blocked. Removal of operator or blocking of
operator arm, results in loss of all braking torque.
When total wear on rotating friction disc (5) reaches 5/32”, the disc
must be replaced. At this point the overall thickness of the disc will be
approximately 1/4”.
1. Set the manual release. Remove cover screws (14), lockwashers
(13), cover (8), locknuts (16), operator assembly (60), jam nuts (15)
and pressure plate (7).
2. Remove rotating friction disc (5) and stationary disc (6). Replace
worn friction disc. NOTE: To facilitate future disassembly, the new
friction discs should be numbered so as to maintain the proper
sequence of the discs.
3. Reassemble brake in reverse order. Be sure the stationary disc (6),
rotating friction discs (5), and pressure plate (7) are in the correct
sequence and position by checking the stamped markings on the
parts. See Figure 5. Adjust magnet gap “A” as outlined under
INSTALLATION (Magnet Adjustment).
MAGNET PLATE REPLACEMENT
(Refer to Figures 2, 3, 6 & 9.)
NOTE: Do not remove operator assembly from brake, unless
motor load is blocked. Removal of operator or blocking of
operator arm, results in loss of all braking torque.
Remove operator assembly (60) as outlined under FRICTION DISC
REPLACEMENT.
DISASSEMBLY
Place the operator assembly so that the coil side is up. Insert a piece
of threaded rod 1/4-20 x “ long through the torque spring holder (49)
into the torque adjusting screw (41) and tighten firmly. With a matching
nut, turn down on the torque spring bushing (52) until the spring pres-
sure is removed from the snap ring (48). Remove the snap ring and
slowly bring up the nut until the spring pressure is removed from the
torque spring bushing. Remove the threaded rod and nut, plus the
torque spring bushing, torque springs (53) and (54), and torque spring
guide (55). Remove the manual release nut (31), washer (30), and
return spring (29). Turn the operator assembly over so that the coil
side is down. Loosen and remove the six hex socket head capscrews
(26). Remove both pivot blocks (32) and (33), operator arm (35), and
torque spring holder (51), release shaft assembly (56) and cam (27).
Remove snap rings (47) and the shock absorber assemblies (46).
REASSEMBLY
Apply a thin coat of grease to the following areas: three bushings in
the magnet plate (20) and (21), the spherical seat of both shock
absorbers (46), and dowel pins (34) in both pivot blocks (32) and (33).
Place shaft (56) through cam (27) engaging pin (57) in cam slot. Insert
shaft and cam through bushing (21) in magnet plate from side opposite
the coils. The stop pin (28) in the cam should be as shown in Figure 6.
Place return spring over shaft on side with coils on, hooking spring (29)
over pin (22). Holding shaft and cam in position, rotate the tang end of
return spring counter clockwise 1/4 turn, engaging tang into slot on
shaft end. Install washer (30 and nut (31). Tighten nut (31) to take up
end play only. There should be spring pressure holding the stop pin the
cam against the stop pin in the magnet plate.
Assemble remaining parts in reverse order of disassembly onto the
new magnet plate. Place the assembled operator onto the brake and
adjust magnet gap “A” as outlined under INSTALLATION (Magnet
Adjustment). See OPERATOR ADJUSTMENT and MANUAL
RELEASE ADJUSTMENT.
OPERATOR ADJUSTMENT
(Refer to Figure 3.)
Check the position of the operator arm (35). The outside flat face of
operator arm should be parallel with outside of magnet plate with brake
de-energized To do this, adjust as follows: Hold set screw (40) and
loosen locknut (16) two full turns. (Typical two places, one each end of
operator arm.) Backoff two set screws (40) two full turns. Block opera-
tor arm with an object so that it is parallel with the magnet plate. Finger
tighten two set screws (40) until they make contact with shock
absorbers (46). Hold set screws in position and tighten locknuts (16).
After removing object, the operator arm should be parallel with magnet
plate. Adjust torque spring length of 1 1/6” as outlined under TORQUE
ADJUSTMENT.
Figure 6.