60 - 4
Section E Hydraulics
9803/6410
Section E
60 - 4
Issue 1
Slew Brake Valve
Operation (JS130)
Slew Brake Release
Pilot pressure at 40 kgf/cm
2
(569 lbf/in
2
), selected by the
operator’s control lever, enters port P, passes over the outer
surface of solenoid spool 1 and enters passageway a. The
oil then passes over the lower end of the pressure reducing
valve spool 2 and enters chamber b, which is connected to
passageway C. As oil enters passageway C, the steel ball 3
is lifted and allows oil to pass over the outer surface of
solenoid spool 4 to outlet port B. Pilot pressure at 40
kgf/cm
2
(569 lbf/in
2
) leaving port B enters the brake port of
the slew motor and releases the brake.
JS02100