Patent ID: 7108164

Claim:
A combustion-powered tool for driving a fastener into a workpiece, comprising: a combustion chamber selectively opened to atmosphere and closed to be hermetically sealed, fuel being introduced into the hermetically sealed combustion chamber to fill the combustion chamber with a fuel/air mixture, the combustion chamber being formed of a combustion chamber frame movable to selectively open the combustion chamber to atmosphere and close the combustion chamber to be hermetically sealed; a spark plug exposed to the combustion chamber for igniting the fuel/air mixture within the hermetically sealed combustion chamber, wherein inner pressure of the combustion chamber increases when the fuel/air mixture is ignited within the hermetically sealed combustion chamber; a driver blade that is moved in accordance with the increase in the inner pressure of the combustion chamber, the fastener being driven into the workpiece caused by the increase in the inner pressure of the combustion chamber; a first switch that is selectively turned ON or OFF, the first switch being turned ON when the combustion chamber frame has reached a predetermined position; a second switch that is selectively turned ON or OFF, the second switch being turned ON when the second switch is manipulated by an operator; and a control unit that controls the spark plug to ignite the fuel/air mixture when both the first switch and the second switch are rendered ON irrespective of an order in which the first switch and the second switch are turned ON.