A cutting tool includes a shaft portion. The shaft portion includes an increased-diameter portion having a diameter larger than a diameter of other portion of the shaft portion. The increased-diameter portion has a recessed portion formed in a peripheral surface of the increased-diameter portion.

A machining tool includes a holder and a cutting head which can be screwed into the holder. The cutting head includes a cutting-edge region and a coupling region. The coupling region includes a flat contact area facing the holder, a cylindrical thread carrier with an external thread adjoining the flat contact area, and a clamping cone adjoining the thread carrier. The holder includes a planar counter-contact area disposed adjacent the flat contact area of the coupling region, a cylindrical internal thread adjoining the planar counter-contact area, and a hollow-conical cone contact area next to the internal thread.

A head replacement-type cutting tool having a holder provided at the attachment hole with the fitting part formed in a tapered shape, and the leading end face is perpendicular to the central axis. The attachment part formed in a tapered shape protrudes on the cutting head from the rear end face perpendicular to the central axis of the cutting part. The cutting head is attached to the holder in such a manner that the attachment part is fitted into the fitting part by screwing the female thread part with the male thread part and the leading end face is in contact with the rear end face. The inner diameter to outer diameter ratio d/D1 which is a ratio of the inner diameter d of the fitting part before being fitted in relation to the outer diameter D1 of the leading end part of the holder is from 0.5 to 0.8.

A screw-in tool and a tool holder for such a screw-in tool. The screw-in tool contains a tool head and a tool shank having an outer thread and a supporting region arranged between the tool head and the outer thread. The supporting region is formed by two conical bearing faces having different cone angles.

A replaceable face-milling head configured for rotating about a central rotation axis A.sub.R. The head includes a cutting portion and an integrally formed threaded shank-connector portion, the latter of which being configured for connecting to a shank. A length-diameter ratio LDR, defined as a cutting portion length L.sub.C divided by a cutting portion diameter D.sub.E, fulfills the condition: LDR≦1.00.

The invention relates to a cutting tool, particularly for use in a tool chuck of a machine tool, including a tool shaft with a center longitudinal axis and a tool head. The tool head is connected to the tool shaft via a positive-locking connection, which locks the movement in the direction of the center longitudinal axis and the positive-locking connection is supplemented by a bonded connection, particularly a soldered connection.

A multi-part modular tool rotatable about a longitudinal tool axis (A), comprising: a machining head; a first holding element comprising a body elongated along the longitudinal axis (A) of the tool, in which a passage extends along the longitudinal axis (A) of the tool; a second holding element which can extend in the passage of the first holding element; wherein the machining head can be connected to the second holding element in such a way that the machining head is fixed firmly to the first holding element at least in the axial direction (A) and/or in the radial direction (R), and wherein the passage of the first holding element and the second holding element are adapted to one another such that during a connection process in which the machining head is connected to the second holding element, the second holding element is movable relative to the first holding element.

A rotary cutting tool includes a replaceable cutting head and a tool holder. The replaceable cutting head includes a forward cutting portion and a rearward mounting portion. The mounting portion includes a male coupling member that includes an external thread defined by external inner and outer cylinders. The external thread has concavely curved external thread roots which each merge with a respective straight external loaded surface at a first external root point. The first external root point is spaced apart from the external inner cylinder by a first external radial distance. The first external radial distance is greater than a third and less than two thirds of the external thread height. The tool holder includes a female coupling member that includes an internal thread. When the rotary cutting tool is in a locked position, the external thread is threadingly engaged with the internal thread.

The rotating tool, in particular a drill, includes a fluted cutting shank made of a resistant material, in particular carbide, extending in an axial direction along a rotational axis. Connecting to the cutting shank in the axial direction is an intermediate shank made of a material of greater elasticity in comparison the resistant material, in particular of tool steel. The intermediate shank includes an insertable cutting insert that may be exchanged. The cutting shank is preferably a cutting shank recycled from a used solid carbide drill.

Disclosed is an assembling and centering structure for a processing tool, the structure having a clamping handle (10), a processing head (20), and a fastening member (30) for connecting and fixing the clamping handle (10) and the processing head (20). An end face accommodation groove (100) of the clamping handle (10) is formed with a concave part (11) and a centering hole (12). The processing head (20) is formed with a convex part (211) and a centering post (222), the convex part (211) matches the concave part (11), and the centering post (222) matches the centering hole (12). Thus, it can be ensured that after assembly, the central axis of rotation of the clamping handle (10) is in a straight line with the central axis of rotation of the processing head (20).