A powder actuated fastening tool including a charge advance apparatus for advancing a powder charge strip relative to a barrel of the tool, wherein the charge advance apparatus includes a rotatable ratchet having teeth for engaging receptacles formed in the powder charge strip, and a charge advance member coupled to a trigger of the tool, wherein the charge advance member acts on the rotatable ratchet to rotate the ratchet in response to actuation and/or release of the trigger, such that the rotation of the ratchet causes advance of the powder charge strip relative to the barrel.

The invention relates to a hand-held machine tool for setting a nail, having a safety mechanism which can be actuated by a user and a button which can be actuated to trigger a setting of the nail. A mixture of flammable gas and air can be ignited in a combustion chamber. A piston is movably arranged in the combustion chamber in order to be accelerated in the setting direction by the combustion gases. There is a stamp on the piston for driving the nail. A compressor for compressing the air in the combustion chamber is directly connected to the combustion chamber via a channel. A valve which connects the channel or the combustion chamber to the environment is opened between the actuating of the safety mechanism and the actuating of the button.

The invention relates to a driving-in tool, comprising a driving-in piston, guided in a cylinder, for driving a nail element into a workpiece, and a combustion chamber which is arranged at the driving-in piston and can be filled with an ignitable fuel-gas mixture. A positive pressure of the fuel-gas mixture in the combustion chamber can be produced by a movement of the driving-in piston. At least one of the two, the combustion chamber or the cylinder, is connected to an external space via a valve member, the positive pressure of the fuel-gas mixture produced by the driving-in piston being selectively adjustable by means of the valve member.

A powder actuated fastening tool including a charge advance apparatus for advancing a powder charge strip relative to a barrel of the tool, wherein the charge advance apparatus includes a rotatable ratchet having teeth for engaging receptacles formed in the powder charge strip, and a charge advance member coupled to a trigger of the tool, wherein the charge advance member acts on the rotatable ratchet to rotate the ratchet in response to actuation and/or release of the trigger, such that the rotation of the ratchet causes advance of the powder charge strip relative to the barrel.

A fastener driving device comprising a combustion chamber, a piston and a fastener channel. The piston is coupled to the combustion chamber and slidable within a sleeve such that combustion gas expansion causes the piston to slide from a first position to a second position. The fastener channel is configured to receive a fastener, wherein when moving from the first to the second position, the piston is configured to engage the fastener. In one embodiment the device comprises a return chamber for receiving gas from the sleeve via a first vent, and a second vent coupled to the return chamber and for supplying combustion gas from the combustion chamber to the return chamber. In another embodiment, the combustion chamber comprises a housing portion, wherein combustion gas expansion acts on the housing portion such that the housing portion moves to open the combustion chamber and exhaust combustion gases.