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.

An angle head holder has a steering assembly and a holder assembly rotatably mounted in the steering assembly. The holder assembly has a cutter spindle, a threaded rod, multiple balls, and a collet. The cutter spindle has a central hole and a first annular groove radially formed in the central hole at a position near a rear end of the cutter spindle. The threaded rod has a second annular groove aligning with the first annular groove to form a ball groove between the threaded rod and the cutter spindle. The balls are arranged in the ball groove. The collet is inserted in the central hole of the cutter spindle from a front end of the cutter spindle and is connected to the threaded rod with threaded connection.

An angle head holder has a steering assembly and a holder assembly rotatably mounted in the steering assembly. The holder assembly has a cutter spindle, a threaded rod, multiple balls, and a collet. The cutter spindle has a central hole and a first annular groove radially formed in the central hole at a position near a rear end of the cutter spindle. The threaded rod has a second annular groove aligning with the first annular groove to form a ball groove between the threaded rod and the cutter spindle. The balls are arranged in the ball groove. The collet is inserted in the central hole of the cutter spindle from a front end of the cutter spindle and is connected to the threaded rod with threaded connection.

A system is proposed that is made up of a tool holder 1, a collet 15 with a clamping nut 19, and a tool insert 27, in which the collet 15 and the tool insert are fixed and positioned on various function surfaces within the tool holder 1. Nevertheless, the clamping means are the same, namely a thread on the tool holder 1.

A tool receptacle for a screw-in tool having a main body, which has a receiving region including at least one conical contact surface for supporting a corresponding conical support surface of the screw-in tool. For thread-protection and for tightening with high concentricity and low production outlay, an insert is disposed in the main body, the insert is movable transversely with respect to the longitudinal axis of the main body and is rotationally-fixed with respect to the main body and has a mating thread for a thread on the screw-in tool.

A tool holder has a holder body, a chuck, and a clamping nut. The chuck has an annular groove, a nut positioning portion, and a cutting surface. The cutting surface is formed on a periphery of the nut positioning portion by cutting. The clamping nut has a protruding edge. When assembling the chuck and the clamping nut, the cutting surface allows the protruding edge to easily avoid and pass by the nut positioning portion, enter the annular groove, and be engaged in the annular groove, which lowers difficulty of assembly. During disassembly, the protruding edge is configured to abut the nut positioning portion, which allows the chuck to be easily detached from the holder body together with the clamping nut when unscrewing the clamping nut from the holder body.