Patent attributes
A hand-held power tool is provided, the operational power of which is provided by a gas combustion mechanism. The gas combustion mechanism comprises a first priming cylinder (2) having a first piston (4) and an air intake valve (6). The priming cylinder (2) is fluidally connected via a transfer valve (8) to a combustion chamber (10) connected to a second delivery cylinder (12) having a second piston (14). In use, the first piston (4) is arranged to compress air and transfer compressed air to the combustion chamber (10) via the transfer valve (8). The combustion chamber (10) is arranged to receive the compressed air from the priming cylinder (2) and fuel gas from the fuel supply port (16). The air and fuel gas are mixed to form an air/fuel gas mixture therein. The combustion chamber (10) is also arranged so that the air/fuel mixture is ignited therein to impart motion onto the second piston (14) and to facilitate the operation of the tool.