Principle Of Operation; Before Nailing; When Nailing - Hitachi NR90GC - 3-1/2" Gas Powered Clipped Head Framing Nailer Technical Data And Service Manual

8-2. Principle of Operation

(1) Before nailing

Fuel is not charged into the nailer in the initial
state. The combustion chamber is released
to the atmosphere (Fig. 4).

(2) When nailing

1) Push up the Pushing Lever [64].
Then the nailer starts operation in the
following order (Fig. 5).
The Switch Plate [34] on the Chamber
[24] pushes the Switch Arm [82] to turn on
the fan switch. The Fan [20] in the
combustion chamber rotates.
The Chamber Head [22] is sealed by the
O-ring [15] and the Chamber [24] surface
is sealed by the O-ring [36]
simultaneously. Thus the combustion
chamber is cut off from the atmosphere.
The convex portion of the Chamber [24]
pushes up the Tension Plate [113] on
Switch Lever (B) [114] to rotate Switch
Lever (B) [114].
The protrusion of the Chamber Head
[22] pushes up the tip of the Cell Lever
[105] to rotate it. Thus the Cell Lever
[105] pushes the back of the fuel cell to
spray fuel into the combustion chamber.
Combustion
chamber
Fan [20]
Chamber [24]
Cylinder Ass'y [42]
Pushing
Lever [64]
Protrusion of
Chamber Head [22]
O-ring [15]
Chamber Head [22]
Fan [20]
Combustion
chamber
O-ring [36]
Chamber [24]
Tension Plate [113]
Convex of Chamber [24]
Switch Plate [34]
Pushing Lever [64]
--- 12 ---
Fuel cell
Trigger [98]
Fig. 4
Cell Lever [105]
Chamber [24]
Trigger [98]
Switch Lever (B)
[114]
Fan switch
Switch Arm [82]
Fig. 5