Swing Brake Operation - jcb JS300 Service Manual

Cylinder block F is splined to output shaft G. Two friction
plates A are splined to the outer edge of the cylinder block
and are interleaved between three counter plates B which
are fixed to the Swing motor casing E.
The brakes are applied when the hydraulic pressure at port
X is zero. Spring C pressure forces piston D down to press
the friction plates and the counter plates together, thereby
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Swing Brake Operation

F
G
A
locking cylinder block F and casing E and preventing
rotation.
The brakes are released when hydraulic pressure is
applied to port X. Oil enters chamber Y and pushes brake
piston D up, against the pressure of spring C, to release
the previously locked friction plates A and counter plates
B. Cylinder block F is now free to rotate within casing E.
C
E D
B
X
Fig 2.
9813/5100-1
Section E - Hydraulics
Swing Motor
Swing Brake Operation
Y
C075120
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