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: LDR1.00.

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 a straight external thread. The tool holder includes a female coupling member that includes a conical internal thread. When the rotary cutting tool is in a locked position, the external thread is threadingly engaged with the internal thread.

An assembly-type cutter includes a shank and a cutter head. The shank has a hole at one end. The hole has a receiving portion, which includes an internal thread and can be treated thermally for increased rigidity. The cutter head has a cutting portion and a connecting portion at opposite ends respectively. The connecting portion includes a threaded member and can also be treated thermally for increased rigidity. The cutter head and the shank are threadedly connectable via the connecting portion and the receiving portion. The threaded member includes a body portion, whose diameter is defined as a root diameter, and an external thread on the body portion. The body portion is slightly tapered such that a locus of the root diameter is inclined.

The invention relates to a screw-in tool (1) and to a tool holder (2) for such a screw-in tool. The screw-in tool (1) contains a tool head (3) and a tool shank (4) having an outer thread (5) and a supporting region arranged between the tool head (3) and the outer thread (5). According to the invention, the supporting region is formed by two conical bearing faces (6, 8) having different cone angles.

A modular cutter head having a holder defining a threaded receiver. The cutter head can be screwed into the threaded receiver. The cutter can comprise an elongated body portion having a cutting end and cutting edge and an elongated coupling portion spaced from the cutting end, with the coupling portion comprising a core and a plurality of generally helically-extending start threads disposed circumferentially about the core. The cutter head may also include a cutting end having a chip flute and an insert seat.

A replaceable cutting head includes a forward cutting portion and a rearward mounting portion. The mounting portion includes a male coupling member that protrudes rearwardly from a head base surface. The male coupling member includes forward and rearward bearing portions and an external thread located therebetween. The forward and rearward bearing portions include respective conically shaped forward and rearward head abutment surface. The forward and rearward head abutment surfaces have the same cone angle. When a cutting tool, including said cutting head and a tool holder having a female coupling member, is in a locked position, the external thread is threadingly engaged in the female coupling member and the forward and rearward head abutment surfaces conically abut corresponding conical shaped surfaces in the female coupling member.

The invention relates to a tool holding fixture (1) for rotationally driven tools (2), said tool holding fixture comprising a rotationally symmetrical holding body (3) which has a front clamping region (4) having a receiving opening (5) for a tool shank (6) of the tool (2), and a rear holding region (7) to be held in a work spindle of a machine tool. In order to achieve a reduced mass, a lower mass moment of inertia and at the same time high stiffness, a sleeve (11), made of a fiber reinforced plastic, is disposed in at least the front clamping region (4).

A replaceable cutting head includes a forward cutting portion and a rearward mounting portion. The mounting portion includes a male coupling member that protrudes rearwardly from a head base surface. The male coupling member includes forward and rearward bearing portions and an external thread located therebetween. The forward and rearward bearing portions include respective conically shaped forward and rearward head abutment surface. The forward and rearward head abutment surfaces have the same cone angle. When a cutting tool, including said cutting head and a tool holder having a female coupling member, is in a locked position, the external thread is threadingly engaged in the female coupling member and the forward and rearward head abutment surfaces conically abut corresponding conical shaped surfaces in the female coupling member.

A rotatable cutting tool, which extends along a tool axis defining an axial direction, includes a cutting formation in a first axial longitudinal end region, which is configured for material ablation on a workpiece, and includes a screw-connection formation in a second axial longitudinal end region opposing the first, which is configured for screw connection with a coupling unit. The cutting tool includes key-contact surface formations diametrically opposing each other with respect to the tool axis, which are configured for torque-transmitting abutting engagement with key surfaces of a key. Each of the key-contact-surface formations includes at least two key-contact surface regions provided with spacing from each other in the circumferential direction about the tool axis, which key-contact surface regions are inclined away from each other such that they form a vertex projecting away from the tool axis.

An assembly-type cutter includes a shank and a cutter head. The shank has a hole at one end. The hole has a receiving portion, which includes an internal thread and can be treated thermally for increased rigidity. The cutter head has a cutting portion and a connecting portion at opposite ends respectively. The connecting portion includes a threaded member and can also be treated thermally for increased rigidity. The cutter head and the shank are threadedly connectable via the connecting portion and the receiving portion. The threaded member includes a body portion, whose diameter is defined as a root diameter, and an external thread on the body portion. The body portion is slightly tapered such that a locus of the root diameter is inclined.