A device (44) for forming a thread in a workpiece has a housing and a plurality of tool receptacles (2) rotatably and displaceably mounted in or on the housing for a respective thread-forming tool, wherein a linear drive and a rotary drive for the tool receptacles (2) are integrated into the housing.

A tool coupling device for coupling a tool can comprise a drive shaft for coupling to the drive, an output shaft for coupling to the tool, the output shaft being rotatable about a central axis (A), a transmission unit connected between the drive shaft and the output shaft and translating a rotational movement of the drive shaft at an input speed (n.sub.S) into a rotational movement of the output shaft at an output speed (n.sub.W) greater than the input speed (n.sub.S) and a non-rotating housing, wherein the transmission unit, and at least a part of the input shaft and a part of the output shaft that are both coupled to the transmission unit, are arranged within the housing, wherein the drive shaft is rotatably mounted on the housing; and wherein the output shaft is rotatably supported solely on the input shaft and is not rotatably supported on the housing.

A tool coupling device for coupling a tool can comprise a drive shaft for coupling to the drive, an output shaft for coupling to the tool, the output shaft being rotatable about a central axis (A), a transmission unit connected between the drive shaft and the output shaft and translating a rotational movement of the drive shaft at an input speed (n.sub.S) into a rotational movement of the output shaft at an output speed (n.sub.W) greater than the input speed (n.sub.S) and a non-rotating housing, wherein the transmission unit, and at least a part of the input shaft and a part of the output shaft that are both coupled to the transmission unit, are arranged within the housing, wherein the drive shaft is rotatably mounted on the housing; and wherein the output shaft is rotatably supported solely on the input shaft and is not rotatably supported on the housing.

A tap tool holder for a tap tool is disclosed. The tap tool has a cylindrical body and a tap extended from the cylindrical body. The tap tool holder includes a bracket sleeve for inserting the tap and a positioning collar. An annular inner step is formed in one end of the bracket sleeve. The positioning collar is carried on the annular inner step. The positioning collar has an outer ring wall, and the outer ring wall is attached to the annular inner step. The positioning collar has an inner ring wall, and a shape of the inner ring wall corresponds to an outer side wall of the cylindrical body so as to sleeve the cylindrical body. With the positioning collar that can be replaced corresponding to tap tools, tap tools of various sizes can be positioned in the bracket sleeve to facilitate tapping.

A tap tool holder for a tap tool is disclosed. The tap tool has a cylindrical body and a tap extended from the cylindrical body. The tap tool holder includes a bracket sleeve for inserting the tap and a positioning collar. An annular inner step is formed in one end of the bracket sleeve. The positioning collar is carried on the annular inner step. The positioning collar has an outer ring wall, and the outer ring wall is attached to the annular inner step. The positioning collar has an inner ring wall, and a shape of the inner ring wall corresponds to an outer side wall of the cylindrical body so as to sleeve the cylindrical body. With the positioning collar that can be replaced corresponding to tap tools, tap tools of various sizes can be positioned in the bracket sleeve to facilitate tapping.

Power drive tools are described. The tools include one or more threading pawls, one or more release pawls, and a drive ring selectively positionable relative to the tool and engaged with the pawls to selectively extend or retract the pawls. Also described are tools that include one or more lights to illuminate a workpiece. Also described are tools having distally located shoulder regions at which force may readily be applied. In addition, gear train assemblies for use in the power drive tools are described.

Power drive tools are described. The tools include one or more threading pawls, one or more release pawls, and a drive ring selectively positionable relative to the tool and engaged with the pawls to selectively extend or retract the pawls. Also described are tools that include one or more lights to illuminate a workpiece. Also described are tools having distally located shoulder regions at which force may readily be applied. In addition, gear train assemblies for use in the power drive tools are described.

Power drive tools are described. The tools include one or more threading pawls, one or more release pawls, and a drive ring selectively positionable relative to the tool and engaged with the pawls to selectively extend or retract the pawls. Also described are tools that include one or more lights to illuminate a workpiece. Also described are tools having distally located shoulder regions at which force may readily be applied. In addition, gear train assemblies for use in the power drive tools are described.

Power drive tools are described. The tools include one or more threading pawls, one or more release pawls, and a drive ring selectively positionable relative to the tool and engaged with the pawls to selectively extend or retract the pawls. Also described are tools that include one or more lights to illuminate a workpiece. Also described are tools having distally located shoulder regions at which force may readily be applied. In addition, gear train assemblies for use in the power drive tools are described.

A tool holder includes a tubular body having a shank on a first axial end portion, a tool gripping portion on a second axial end portion, and an elastic segment interposed between the shank and the tool gripping portion in the axial direction of the body. The elastic segment is more elastically deformable along the axial direction and around a circumferential direction of the tubular body than the shank and the tool gripping portion owing to a plurality of voids that extend through the elastic segment from an outer peripheral side of the tubular body to an inner peripheral side of the tubular body. Each of the voids includes segments that extend around the circumferential direction and along the axial direction of the tubular body.