A rotatable chuck for clamping a shank portion of a rotatably operating machining tool includes a rotatable chuck body provided with a cylindrical bore concentric with a rotation axis of the chuck body. The circumferential surfaces of a clamping portion of the bore are arranged to apply a clamping force around the circumference of the shank portion of the tool when it is mounted in the chuck to fixate the tool in the chuck. The chuck is provided with auxiliary pull out preventing means for preventing inadvertent pull out of the tool in the axial direction of the bore during machining operation, as well as auxiliary rotary preventing means for preventing inadvertent rotation in at least one direction in relation to the chuck during machining operation. The auxiliary pull out and rotary preventing means include an attachment member positionable in an inner portion of the bore and attachable to the shank portion to be clamped, such that the tool and the attachment member will be prevented from being pulled apart in the axial direction and from being rotated in at least one direction in relation to each other.

Disclosed is a mounting device (6) including a receiving opening (8) with a circular inner locating surface (10) which is coaxial with the axis of rotation (3) and serves for engagement with radially outer vertices (24) of the polygon profile of a holding pin (23). Arranged adjacent to the inner locating surface is a positioning disk (14) which has an opening (15) coaxial with the axis of rotation (3) and of such polygonal shape and size that the polygon profile of the holding pin (23) engaging in the opening (15) is supported in the opening (15) in a manner preventing relative rotation.

Portable milling machine having a housing, a spindle and a clamping nut, which, as part of a tool holder, can be rotatably connected to the spindle and detached therefrom in order to clamp and unclamp a milling tool, and the portable milling machine having a spanner, which can be moved relative to the spindle axially between an engaged position and a disengaged position, the spanner interlockingly surrounding the clamping nut at least in portions in the circumferential direction in the engaged position and, when the spanner is in the disengaged position, the clamping nut being rotatable relative to the spanner, the spanner being connected to the housing of the portable milling machine for conjoint rotation such that, when the spanner is in the engaged position, the clamping nut can be connected to the spindle and detached therefrom by manually rotating the spindle.

Portable milling machine having a housing, a spindle and a clamping nut, which, as part of a tool holder, can be rotatably connected to the spindle and detached therefrom in order to clamp and unclamp a milling tool, and the portable milling machine having a spanner, which can be moved relative to the spindle axially between an engaged position and a disengaged position, the spanner interlockingly surrounding the clamping nut at least in portions in the circumferential direction in the engaged position and, when the spanner is in the disengaged position, the clamping nut being rotatable relative to the spanner, the spanner being connected to the housing of the portable milling machine for conjoint rotation such that, when the spanner is in the engaged position, the clamping nut can be connected to the spindle and detached therefrom by manually rotating the spindle.

A method for holding a spindle of a mobile power tool in order to allow an opening and/or a closing of a tool fitting by turning an operating part of the tool fitting relative to the spindle, where the spindle is rotationally coupled to an electric motor. The method includes detecting a rotation of the spindle and/or of the electric motor in a first direction while a setpoint angular velocity is zero and controlling the electric motor to generate a torque in a second direction which is opposite to the first direction.

In a handheld machine tool having a tool housing, in which a drive motor is situated for driving a drive element equipped with at least one clamping surface, to which a spindle-locking device equipped with a blocking element and at least one spindle cylinder is assigned, the at least one spindle cylinder being able to be clamped in a spindle-lock operation of the spindle-locking device between the at least one clamping surface and the blocking element in order to prevent the drive element from rotating relative to the tool housing, the spindle-locking device has an impingement element, which is developed to impinge on the at least one spindle cylinder with a specified force in the direction of the at least one clamping surface.

An apparatus configured to convert a rotary machine to a non-rotary machine is provided. The apparatus may include a tool body that engages a rotary head of a CNC mill and a rotation restraint member that is fixed at a stationary position relative to a rotational axis of the rotary head. An arm of the tool body may engage the rotation restraint member to prevent rotation of the tool body. A cutting tool may be coupled to the tool body such that rotation thereof is also fixed. The arm of the tool body may include an elongated aperture that allows for slight pivoting of the tool body and the cutting tool to facilitate chip removal and cutting in opposing directions. Related methods are also provided.

A spindle locking device for a portable machine tool includes a locking unit and a movement activation unit. The locking unit has a movably mounted locking element configured to lock a spindle of the portable machine tool in at least one direction, and an operating element configured to actuate the locking element. The movement activation unit is configured to pretension the locking element in a direction towards a locking position, at least when the operating element is in an unactuated position.

A miniature internal boring tool including two to four shank flat surfaces and two to four integrally formed teeth. The outermost points of cutting edges of the teeth define an outer cutting diameter (OD) fulfilling the condition: 2 mm<OD<9 mm.

A method for tightening or releasing a screw connection between a core drilling device and a core bit, the core drilling device including a core bit and a motor, the core bit being able to be caused to move in a first direction of rotation while, by activation of the motor during the tool change, a counter-torque is generated in order to tighten or release the twist lock between the core drilling device and the core bit. A core drilling device for carrying out the method. By activation of the motor of the core drilling device, the motor can be caused to operate counter to the movement of the core bit in the first direction of rotation. As a result, a difference between the torque in the first direction of rotation and the counter-torque can be significantly increased by activation of the motor.