Combustion powered tool with combustion chamber delay

摘要

A combustion powered tool has 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. The tool includes a housing constructed and arranged to enclose the power source, a combustion chamber defined at an upper end of the housing and a cylinder disposed be in fluid communication with the combustion chamber. A valve member is disposed to periodically close the combustion chamber. A piston is associated with the driver blade and is configured for reciprocal movement within the cylinder between a start position and a driving position. Also included on the tool is a nosepiece having a workpiece contact element configured for contacting a workpiece. The workpiece contact element is movable relative to the nosepiece, and upon such contact, the movement of the workpiece contact clement causes the valve member to close the combustion chamber. A delay apparatus is engageable with the workpiece contact element and the linkage for delaying the opening of the combustion chamber by the valve member until the piston returns to the start position after driving the fastener.