Abstract: A tool shaft, especially for drills of the percussive type, such as hammer drills, is adapted to be mounted in a tool holder having fixed driving elements, and the shaft is therefore provided with guiding recesses driving recesses and interconnecting transition recesses which recesses in combination with the driving elements form a type of bayonet joint.In order to improve the universal applicability of the tool shaft also in connection with tool holders of the type having radially movable driving elements, the driving recesses are formed with a radial depth exceeding that of the guiding recesses, and each of the guiding recesses has a cross-sectional shape so as to define a rib or edge between each associated pair of guiding and driving recesses so as to prevent spherical or cylinder shaped driving elements of the radially movable type from being moved unintentionally from the driving recess into the associated guiding recess.

Abstract: The invention relates to a combination of a tool holder having a socket member with a cylindrical axial bore, and a tool shaft releasably received therein. A driving element is displaceably mounted in the socket member so as to be movable between an extended position in which part of the driving member extends into the axial bore, and a retracted position in which the driving member is retracted from the bore, and the driving element is biased towards its extended position by spring means. The tool shaft received in the tool holder has a transversely extending recess receiving the driving element in its extended position, whereby the tool shaft is locked in the tool holder. Adjacent to the free end of the tool shaft the said recess defines an abutment surface cooperating with an inner surface part of the driving element in its extended position so as to prevent axial withdrawal of the tool shaft from the axial bore of the socket member.

Abstract: The disclosure relates to a combination of a tool holder having a socket member with a cylindrical axial bore, and a tool shaft releasably received therein. A driving element is displaceably mounted in the socket member so as to be movable between an extended position in which part of the driving member extends into the axial bore, and a retracted position in which the driving member is retracted from the bore, and the driving element is biased towards its extended position by spring means. The tool shaft received in the tool holder has a transversely extending recess receiving the driving element in its extended position, whereby the tool shaft is locked in the tool holder. Adjacent to the free end of the tool shaft the said recess defines an abutment surface cooperating with an inner surface part of the driving element in its extended position so as to prevent axial withdrawal of the tool shaft from the axial bore of the socket member.

Abstract: In a drilling device, especially a hammer drill, a tool is coupled to a tool receiving means by co-operating male and female coupling elements which ensure uniform rotational motion of the tool in relation to the tool receiving means; additional transition and guiding surfaces being provided for inserting or removing the tool single-handed.