Hitachi ZW180, Техническое руководство

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COMPONENT OPERATION / Drive Unit
T3-9-36
MANUAL SPOOL (EMERGENCY TRAVEL
SPOOL)
When the solenoid valve cannot be operated due to
electric malfunction (e.g.: disconnection), the control
valve is shifted to forward 2nd speed or reverse 2nd
speed by manually operating this spool.
This spool is used for self-traveling of the vehicle to the
place for maintenance in an emergency or something.
IMPORTANT: Before operating the manual spool,
stop the engine. If operating the
manual spool while the engine is
running, the vehicle may start
moving.
Operation
•
Forward 2nd Speed
When shifting to forward 2nd speed, push in
forward emergency travel spool (3) and 2nd
speed emergency travel spool (6) each by 5 mm
(0.2 in), and turn them 90
°
while holding them.
Pressure oil regulated to the regulator pressure
flows to passage (b) through passage (a) opened
by forward modulation spool (2), flows to the
forward clutch, and connects the clutch.
As for the 2nd speed clutch, pressure oil flows to
oil passage (f) through oil passage (e) opened by
2nd speed modulation spool (7), flows to the 2nd
speed clutch, and connects the clutch.
•
Shift from Forward 2nd speed to Reverse 2nd
Speed
When turning forward emergency travel spool (3)
by 90
°
, the spool returns to the original position by
the force of spring (1).
As for reverse 2nd speed, similarly to forward 2nd
speed, push in reverse emergency travel spool
(5) by 5 mm, and turns it 90
°
.
Pressure oil regulated to the regulator pressure
flows to oil passage (d) through oil passage (c)
opened by reverse modulation spool (4), flows to
the reverse clutch, and connects the clutch.
IMPORTANT: Do not operate forward emergency
travel spool (3) and reverse
emergency travel spool (5).
Breakage of the clutch can be
caused.