Hitachi NT 65MA2, Технические данные и руководство по обслуживанию

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(3) During return: (Fig. 7 and Fig. 8)
1) When either Pushing Lever (A) [41] or Trigger (A)
[52] is released, Plunger (A) [66] goes down and the
compressed air in the accumulator flows into the
valve piston lower chamber.
2) As the air pressure in the valve piston lower chamber
increases to overcome the air pressure applied on
the upper portion of Valve Piston (B) [63], Valve
Piston (B) [63] is forced upward. When this occurs,
the exhaust valve is closed and the air supply vent is
opened.
3) When the air supply vent opens, the compressed air
in the accumulator ( ) passes through the air
passage and flows into the head valve chamber to
push down Head Valve (A) [10]. As a result, Head
Valve (A) [10] and Cylinder [11] are sealed and, at
the same time, Head Valve (A) [10] and Exhaust
Cover [5] are released to open the exhaust vent.
4) The compressed air at the upper portion of the
Piston [15] is discharged into the atmosphere
through the exhaust vent. In this way, the air
pressure at the upper portion of the Piston [15] is
reduced, and the greater pressure of the air
accumulated in the return air chamber pushes the
Piston [15] upward.
5) If the air pressure at the lower portion of the Piston
[15] is higher than that of the atmosphere after the
Piston [15] has fully returned, the excess air
pressure is discharged into the atmosphere through
the clearance between the Piston Bumper [25] and
the driver blade.
Fig. 7
Fig. 8 Control valve section
Exhaust Cover [5]
Exhaust vent
Accumulator
Head
Valve (A) [10]
Cylinder [11]
Return air
chamber
Piston [15]
Piston
Bumper [25]
Driver blade
Pushing Lever (A) [41]
Trigger (A) [52]
Control valve
section
Air passage
To the head valve chamber
Air supply vent
Accumulator
Air passage
Exhaust valve
Valve piston
lower chamber
Plunger (A) [66]
Valve Piston (B) [63]
Head valve chamber