Patent ID: 6913088

Claim:
A hammer drill and/or percussion hammer, comprising: at least one handle having a grasping point for the holding of, and applying of pressure to, the hammer drill and/or percussion hammer by an operator; an air spring hammer mechanism having a drive piston that moves back and forth and a percussion piston that is driven by the drive piston, a hollow space accommodating an air spring and being formed between the drive piston and the percussion piston; a no-load channel connecting the hollow space with the surrounding environment of the air spring hammer mechanism and ventilating the hollow space during no-load operation; a valve, situated in the no-load channel, for opening and closing the no-load channel; a hammer housing that surrounds at least the air hammer percussion mechanism; a detection apparatus that detects a pressure force that is applied to the handle by the operator and that is situated in the flow of force between the grasping point and the hammer housing; and wherein the valve is controlled dependent on the detected pressure force.