SECTION 5 – SWING DRIVE
5-2
USTC
January 15, 2001
SWING MOTOR
The swing motor mounts directly to the swing brake.
A seal kit is available for the swing motor. Refer to
the Parts Manual for component information.
SWING BRAKE
The swing brake is a static brake. It is engaged after
pressure drops in the swing motor and remains en-
gaged until pressure rises. Compression springs
clamp friction disks and hydraulic pressure over-
comes the spring load and releases the brake.
Adjustment
A flow control valve is located on the brake inlet line.
It meters the flow out of the brake. The brake should
engage and stop rotation in one to two seconds.
To adjust, loosen the set screw on flow control valve.
If the turntable continues to rotate, turn the adjust-
ment knob counterclockwise. If the turntable stops
abruptly (less than one second) turn the adjustment
knob clockwise.
After adjusting, tighten the set screw.
Disassembly
CAUTION: DO NOT CLAMP OR
OTHERWISE RESTRAIN COVER FROM
MOVING WHILE REMOVING COVER BOLTS.
HIGH COMPRESSIVE SPRING LOAD WILL
CAUSE COVER TO FLY ONCE RELEASED.
1. Loosen four capscrews from the input end of the
brake. Alternately unscrew bolts 1/2 turn at a
time until all internal spring force is relieved.
Remove the cover. Check for broken springs and
replace, if necessary.
Figure 5-2. Swing Motor Assembly