STT113 TOWER CRANE OPERATION AND SERVICE MANUAL
7B
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5
III. Trolley brake (see fig. 7-3-1)
Description: It is an electromagnetic brake, which is braked when switched off. It has
independent power supply.
1.
Working principle of trolley brake
Fig. 7-3-1
Braking:
When the exciting coil switching off, the electromagnetic attraction
disappears, The brake spring
(2)
pushes the friction disc
(5),
then the brake disc (6)
enters into brake state.
Brake release:
When current entering into the exciting coil, the armature is attracted,
which drives the friction disc
(5
), compress the spring (2), and make the brake disc
entering into releasing state. The brake is ready for next brake when the current is cut
off.
Clearance adjustment:
Remove the protective cover (9) and screw (8). Move the
disc by screw, until it lean against the cover of the latch. Move the disc again, and
locked it in the 3
rd
. At this time, the clearance is 0.8 to 1.2mm
Brake moment adjustment:
It is already adjusted in the manufacturer.
Manual brake release:
Tighten the release nut
(3)
. Do not forget to unscrew the nut
when restarting.
1. Exciting coil
2. Spring
3. Release nut
4. Moving armature
5. Friction disk
6. Brake disk
7. Brake lining
8. Screw
9. Protective cover
7
6
5
4
8
9
1
2
3
E
