Patent ID: 7293541

Claim:
A combustion-type power tool comprising: a housing having one end; a cylinder head disposed at the one end and formed with a fuel injection passage; a cylinder disposed in and fixed to the housing, the cylinder defining an axial direction; a piston slidably disposed in the cylinder and reciprocally movable in the axial direction; a combustion chamber frame disposed in the housing and movable in the axial direction, the combustion chamber frame being abuttable on the cylinder head to provide a combustion chamber in cooperation with the cylinder head and the piston; a fan rotatably disposed in the combustion chamber for agitating and mixing an air with a combustible gas injected into the combustion chamber through the fuel injection passage; and an ignition unit comprising an ignition plug exposed to the combustion chamber and having a tapered tip end portion providing an acute angle of less than or equal to 45 degrees, and an ignition ground disposed in opposition to the tapered tip end portion in the axial direction so as to generate a spark between the ignition plug and the ignition ground to ignite a mixture of air and the combustible gas, to thus provide a fire.