Operation Principle - Hitachi NT65MA3 - 2-1/2 Angled Finish Nailer Service Manual

8-3. Operation Principle

(1) Before nailing: (Fig. 5 and Fig. 6)
1) When compressed air is fed to the main body, it fills
the accumulator (
2) At the same time, the compressed air flows into the
valve piston lower chamber of the control valve
section and forces Valve Piston (B) [65] upward.
Also, the compressed air is fed through the air
supply vent and air passage to the head valve
chamber. As a result, the Head Valve Spring [8] is
pushed down together to seal Head Valve (A) [10]
and Cylinder [11].
(2) When nailing: (Fig. 5 and Fig. 6)
1) When Pushing Lever (A) [40] and Trigger (A) [53]
are operated together and Plunger (A) [68] is
pushed upward, the compressed air in the valve
piston lower chamber is discharged from the bottom
of Plunger (A) [68]. As a result, the compressed air
in the accumulator (
(B) [65], blocking the air supply vent and opening the
exhaust valve.
2) When the exhaust valve opens, the compressed air
in the head valve chamber is discharged into the
atmosphere through the air passage.
3) When the air pressure applied on the bottom surface
of Head Valve (A) [10] overcomes the strength of the
Head Valve Spring [8], Head Valve (A) [10] is
pushed upward. At this time, Head Valve (A) [10]
seals with the Exhaust Cover [5], blocking the
passage to the exhaust vent.
4) When Head Valve (A) [10] goes up, the compressed
air in the accumulator flows rapidly into the Cylinder
[11], forcing the Piston [15] downward to strike the
nail. When the Piston [15] passes the cylinder hole,
the compressed air flows into the return air chamber
and is accumulated there.
).
) pushes down Valve Piston
Exhaust Cover [5]
Exhaust vent
Head Valve
Spring [8]
Head
Valve (A) [10]
Accumulator
Piston [15]
Cylinder [11]
Return air
chamber
Pushing Lever (A) [40]
To the head valve chamber
Air passage
Plunger (A) [68]
Fig. 6 Control valve section
--- 11 ---
Head valve chamber
Air passage
Control valve
section
Trigger (A) [53]
Nail
Fig. 5
Accumulator
Air supply vent
Exhaust valve
Valve Piston (B) [65]
Valve piston
lower chamber