| 20080245840 | Pneumatic nailer - A pneumatic nailer comprising a frame defining a fastener ejection opening, and an elongated driver chamber. The driver chamber in turn defines a peripheral wall, a first end away from the fastener ejection opening and a second end towards the fastener ejection opening. The nailer also comprises trigger member and a piston member movable between a first position and a second position. The piston member comprises a piston driver slidably mounted in the driver chamber. When the piston member is moved towards the first position, the piston driver is moved towards the driver chamber first end; when the piston member is moved towards the second position, the piston driver is moved towards the driver chamber second end. The piston driver subdivides the driver chamber in two subchambers, namely (1) a first subchamber on one side of the piston driver, and comprising a fluid inlet for selectively admitting compressed air in the first subchamber in order to increase the pressure therein and urge the piston member towards said driver chamber second end, and (2) a second subchamber on another side of the piston driver, the second subchamber for fluid communication with the atmosphere through the fastener ejection channel. The piston member also comprises a striking member carried by the piston driver and engaging the fastener ejection opening at least when the piston member is in the second position. The piston member also comprises a selectively open exhaust passage allowing fluid communication between the first subchamber and the second subchamber, the exhaust passage being open at least when the piston member is in the striking position. When the piston member moves from the second position to the first position, air flows from the first subchamber towards the second subchamber through the exhaust passage, and from the second subchamber outwardly into the atmosphere through the fastener ejection opening. | 10-09-2008 |
