Patent ID: 6145724
Filing Date: 2000-11-14
Classification: B25C

Abstract:
A combustion powered tool having a self-contained internal combustion power source constructed and arranged for creating a combustion for driving a driver blade to impact a fastener and drive it into a workpiece, comprising:a housing constructed and arranged to enclose the power source;a combustion chamber defined at an upper end of said housing;a cylinder disposed in said housing to be in fluid communication with said combustion chamber;a valve member disposed in said housing to periodically open and close said combustion chamber;a piston associated with the driver blade and configured for reciprocal movement within said cylinder between a start position located at a first end of said cylinder and a driving position located at a second end of said cylinder;a nosepiece having a workpiece contact element connected to said valve member and configured for contacting a workpiece into which a fastener is to be driven, said workpiece contact element being movable relative to said nosepiece, and upon said contact, such movement of said workpiece contact element causing said valve member to close said combustion chamber; anddelay means actuated and engageable by said driver blade as it descends to impact the fastener, and with said workpiece contact element, so that said delay means prevents said workpiece contact element from moving relative to said nosepiece and said valve from opening said combustion chamber while said driver blade engages said delay means for delaying the opening of said combustion chamber by said valve member until said piston returns to said start position after driving the fastener.