In the internal milling machine according to the invention for milling a work piece that rotates during machining with an annular internal milling cutter (5) on the one hand side the Z slide (4a, b) of each tool support (3a, b) includes a pass through opening and on the other hand side the transversal slide (7) supporting the internal milling cutter (5) is move able in the X-direction, the running direction of the mounting surface (1a) of the bed (1) wherein the mounting surface slopes downward in a forward direction. Based on this general configuration and in particular the arrangement of the Z-slides (6a, b) for the at least one tool support (3a, b) outside of the Z-supports (16a, b) for the opposite spindle stock (2) yields advantageous centers of gravity in particular of the move able components and a high level of stability of the machine and therefore high level of machining precision of the machine.

In the internal milling machine according to the invention for milling a work piece that rotates during machining with an annular internal milling cutter (5) on the one hand side the Z slide (4a, b) of each tool support (3a, b) includes a pass through opening and on the other hand side the transversal slide (7) supporting the internal milling cutter (5) is move able in the X-direction, the running direction of the mounting surface (1a) of the bed (1) wherein the mounting surface slopes downward in a forward direction. Based on this general configuration and in particular the arrangement of the Z-slides (6a, b) for the at least one tool support (3a, b) outside of the Z-supports (16a, b) for the opposite spindle stock (2) yields advantageous centers of gravity in particular of the move able components and a high level of stability of the machine and therefore high level of machining precision of the machine.

A slot milling disc has an outer peripheral surface provided with a number of cutting edges, an attachment arrangement allowing rotary preventing attachment of the slot milling disc to a rotatable mounting shaft and at least one flushing fluid channel having a confined cross-section and extending within the milling disc from an inlet opening located in a central part of the disc and configured to be connected to a source of flushing fluid to at least one outlet opening in the peripheral surface of the disc. The flushing fluid channel has an inner channel portion extending from the inlet opening towards the peripheral surface and ending before reaching the peripheral surface and at least one outer channel portion extending from the inner channel portion while changing direction of the flushing fluid channel and extending to the at least one outlet opening.

A slot milling disc has an outer peripheral surface provided with a number of cutting edges, an attachment arrangement allowing rotary preventing attachment of the slot milling disc to a rotatable mounting shaft and at least one flushing fluid channel having a confined cross-section and extending within the milling disc from an inlet opening located in a central part of the disc and configured to be connected to a source of flushing fluid to at least one outlet opening in the peripheral surface of the disc. The flushing fluid channel has an inner channel portion extending from the inlet opening towards the peripheral surface and ending before reaching the peripheral surface and at least one outer channel portion extending from the inner channel portion while changing direction of the flushing fluid channel and extending to the at least one outlet opening.

An elliptical ultrasonic machining device powered by non-contact induction mainly includes an induction power supply device and an elliptical ultrasonic spindle shank, wherein: induction power supply secondary units of the induction power supply device encircle a spindle shank shell of the elliptical ultrasonic spindle shank; induction power supply primary units are arranged at a primary magnetic core seat outside the elliptical ultrasonic spindle shank; the primary magnetic core seat and the elliptical ultrasonic spindle shank have a same circle center, and a small gap exists between the primary magnetic core seat and the elliptical ultrasonic spindle shank; the primary magnetic core seat is fastened on a machine tool spindle seat of a machine tool through a support and keeps still; the elliptical ultrasonic spindle shank is mounted on a machine tool spindle through a taper shank and rotates with the spindle in a high speed.

An elliptical ultrasonic machining device powered by non-contact induction mainly includes an induction power supply device and an elliptical ultrasonic spindle shank, wherein: induction power supply secondary units of the induction power supply device encircle a spindle shank shell of the elliptical ultrasonic spindle shank; induction power supply primary units are arranged at a primary magnetic core seat outside the elliptical ultrasonic spindle shank; the primary magnetic core seat and the elliptical ultrasonic spindle shank have a same circle center, and a small gap exists between the primary magnetic core seat and the elliptical ultrasonic spindle shank; the primary magnetic core seat is fastened on a machine tool spindle seat of a machine tool through a support and keeps still; the elliptical ultrasonic spindle shank is mounted on a machine tool spindle through a taper shank and rotates with the spindle in a high speed.

A rotary milling tool has a tool holder and a milling head releasably attached thereto. The milling head has a plurality of angularly spaced apart peripherally disposed cutting edges which form an effective cutting edge. The milling head has a head through recess opening out to the head forward and rearward surfaces. The recess includes a centering region and a driven region, the driven region being axially forward of, and non-identical to, the centering region. The driven region has at least one driven surface facing opposite a rotational direction. The centering region has at least one radially inwardly facing radial centering surface located axially rearward of, and radially outward from, the at least one driven surface. The two opposing extremities of the effective cutting edge define two parallel planes respectively between which both the at least one driven surface and the at least one radial centering surface are disposed.

A rotary milling tool has a tool holder and a milling head releasably attached thereto. The milling head has a plurality of angularly spaced apart peripherally disposed cutting edges which form an effective cutting edge. The milling head has a head through recess opening out to the head forward and rearward surfaces. The recess includes a centering region and a driven region, the driven region being axially forward of, and non-identical to, the centering region. The driven region has at least one driven surface facing opposite a rotational direction. The centering region has at least one radially inwardly facing radial centering surface located axially rearward of, and radially outward from, the at least one driven surface. The two opposing extremities of the effective cutting edge define two parallel planes respectively between which both the at least one driven surface and the at least one radial centering surface are disposed.

A rotary tool can be adapted for removing material from a workpiece such as a lower receiver. A rotary tool can have an adapter with a major diameter, and a cutter head with a minor diameter. The major diameter of the adapter can reduce deflection and chatter, while the minor diameter of the cutter head can be used to manufacture lower receivers with accuracy. The rotary tool can be adapted to be engaged with a rotary power tool.

Tool holder for a tool for machining workpieces, with a tool holder body, which defines a longitudinal axis, on which a tool mount for securing a tool is formed and on which a tool holder interface for fixating the tool holder to a holder shaft is formed, wherein the tool holder interface comprises: a tool holder plane surface oriented transversely to the longitudinal axis, against which a holder shaft plane surface can abut to establish a defined relative position in longitudinal direction between the tool mount and the holder shaft, a tool holder cone section, which is polygonal in a cross-section and which can engage with a correspondingly polygonal holder shaft cone section to establish a defined relative position in tangential direction between the tool mount and the holder shaft, and a tool holder cylinder section which can act together with a corresponding holder shaft cylinder section.