| 摘要 |
A protable gas-fired fastener driving tool in which the tool cannot be operated until the combustion chamber is closed and the combustion chamber cannot be reopened after ignition until the trigger is released. The operation of the trigger is permitted by the actuation of a bottom trip mechanism which controls the movement of a sleeve mechanism that regulates the opening and closing of the combustion chamber. During the driving action, the combustion gases above the piston are evacuated through valved openings in the cylinder adjacent the bottom thereof. The piston contacts a bumper at the bottom of its travel and the difference between the vacuum in the combustion chamber and atmospheric air acts to return the piston to its driving position. |
