Abstract: A device for transmitting impulse-like blows to a continuously rotatable tool bit (6) is formed as an axially extending adapter (1) having a first chuck for the tool bit (6) and being insertable at a trailing end into a second tool bit chuck in a manually operated tool equipped with a striking mechanism. The adapter (1) has a housing (2) containing a unit for superimposing a second blow component on the first impulse blow component produced by the striking mechanism, so that an impulse-like drilling blow can be transmitted to the drill bit (6) made up of an axially directed blow component and a torsional blow component.

Abstract: A manually operable tool, such as a hammer drill, for drilling and/or removing material in at least one of brittle material and low ductile material, has a continuously rotatable chuck (8) and a motor driven striking mechanism (1) for transmitting impulse-like blows to a tool bit (9) held in the chuck (8). The tool includes members (5) for transmitting impulse-like blows composed of superimposed axially-directed blows and torsional blows to the tool bit (9) in the chuck for forming drilling blows. Further, an adaptor can be provided for attachment to the hammer drill containing the members (5) for affording the superimposed blows.

Abstract: A tool bit chuck for holding a bit (1) with axially extending grooves (2) closed at the ends thereof spaced apart in the axial direction. Latching elements (4) in the form of cylinders are radially displaceable into and out of the grooves (2). The latching elements (4) have an axis of rotation extending transversely of the axis of the receiving sleeve (3) in the chuck, whereby the latching elements (4) act as roll bodies in the event of an axial shift between the bit (1) and the receiving sleeve (3) so that friction which could result in premature wear, is prevented.

Abstract: A tool bit chuck for a bit (1) having axially extending latching grooves (2) closed at the opposite ends spaced apart in the axial direction, and axially extending rotary entrainment grooves (3) open at the trailing end of the bit. The chuck has entrainment elements (8) and radially displaceable latching elements (8). The latching elements (4) provide axially directed retention of the bit (1), while the entrainment elements (8) transmit torque to the bit (1). The entrainment elements are shaped as roll bodies, such as cylinders, to prevent wear caused by friction.