--- 11 ---
(3) During return: (Fig. 7 and Fig. 8)
1) When either Pushing Lever (A) [42] or Trigger
(A) [25] is released, Plunger (A) [62] 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) [59], Valve Piston (B) [59] 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) [12].
As a result, Head Valve (A) [12] and Cylinder
[19] are sealed and, at the same time, Head
Valve (A) [12] and Exhaust Cover [8] are
released to open the exhaust vent.
4) The compressed air at the upper portion of the
Piston [14] is discharged into the atmosphere
through the exhaust vent. In this way, the air
pressure at the upper portion of the Piston [14]
is reduced, and the greater pressure of the air
accumulated in the return air chamber pushes
the Piston [14] upward.
5) If the air pressure at the lower portion of the
Piston [14] is higher than that of the
atmosphere after the Piston [14] has fully
returned, the excess air pressure is discharged
into the atmosphere through the clearance
between the Piston Bumper [20] and the driver
blade.
Fig. 7
Control valve
section
Air passage
Trigger (A) [25]
Nail
Driver blade
Cylinder [19]
Accumulator
Head Valve (A) [12]
Exhaust vent
Head valve
chamber
Exhaust Cover [8]
Return air
chamber
Pushing Lever (A) [42]
Fig. 8 Control valve section
Air supply
vent
To the head valve chamber
Plunger (A) [62]
Valve piston
lower chamber
Valve Piston (B) [59]
Air
passage
Accumulator
Exhaust valve
Piston [14]
Piston
Bumper [20]
