A cutter holder structure comprises a cutter arbor and a connecting shaft having a tapered section at one end thereof. One end of the tapered section is formed with a first inner screw hole, and another end of the tapered section is formed with a second inner screw hole. The connecting shaft further has a horizontal positioning hole that penetrates through the connecting shaft. Two ends of the positioning hole are formed with cylindrical holes. A reduced hole is defined between the cylindrical holes. A nut has a third inner screw hole at one end and an axial hole at another end. The nut further has a horizontal countersink hole and a horizontal fourth inner screw hole. An eccentric distance is defined between a center of the countersink hole and a center of the fourth inner screw hole. A screw is inserted through the countersink hole and locked into the fourth inner screw hole.

A cutter holder structure comprises a cutter arbor and a connecting shaft having a tapered section at one end thereof. One end of the tapered section is formed with a first inner screw hole, and another end of the tapered section is formed with a second inner screw hole. The connecting shaft further has a horizontal positioning hole that penetrates through the connecting shaft. Two ends of the positioning hole are formed with cylindrical holes. A reduced hole is defined between the cylindrical holes. A nut has a third inner screw hole at one end and an axial hole at another end. The nut further has a horizontal countersink hole and a horizontal fourth inner screw hole. An eccentric distance is defined between a center of the countersink hole and a center of the fourth inner screw hole. A screw is inserted through the countersink hole and locked into the fourth inner screw hole.

The present invention relates to a tool (10) for machining a workpiece, comprising a cutting head (12) which comprises a sleeve (16) and a cutting element (18) which is fixed to the sleeve (16), and comprising a holder (14) to which the cutting head (12) can be detachably fixed. In an assembled state of the tool (10), the cutting head (12) and holder (14) are screwed to each other via an internal thread (40) which is arranged in the sleeve (16) and an external thread (42) which corresponds thereto and which is arranged on the holder (14). In addition, in the assembled state of the tool (10), the cutting head (12) and holder (14) contact each other along a first axial bearing surface (36) which is arranged on the sleeve (16) and a second axial bearing surface (38) which corresponds thereto and which is arranged on the holder (14), and along a first conical bearing surface (44) which is arranged on the sleeve (16) and a second conical bearing surface (46) which corresponds thereto and which is arranged on the holder (14).

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.

A system includes a component to be machined, the component having a plastic base body having an outer diameter and a longitudinal axis and at least one clamping auxiliary structure, and a clamping element configured to clamp the component using the clamping auxiliary structure. The clamping element includes at least one clamping jaw having at least one counter-clamping auxiliary structure that is configured to engage the clamping auxiliary structure and to fix the component in an interference-fit manner in the axial direction with respect to the clamping element. Also a machining method using the system.

A quick-changing brazed drill includes a drill body and a quick-changing joint. The drill body is connected to the quick-changing joint detachably, and a vent hole is provided at a connection point between the drill body and the quick-changing joint. The drill body has a cylindrical structure, an interior of a front end of the drill body is hollow, and an outer side of the front end of the drill body is provided with 2-6 grooves. The quick-changing joint includes a transition block and a rear cover; a rear end of the transition block is connected to the rear cover by an external thread; a snap-fit area is provided between the transition block and the rear cover; a middle portion of the transition block is provided with a first threaded hole and is connected to a rear end of the drill body.

A fixture for machining wheel outer rim without trace includes a positioning and clamping portion and a flexible support portion. A base is fixed on a bottom plate, and a screw is configured to compress an expanding pressure plate during being tightened so that the outer circumference of an expanding sleeve expands a center hole of a wheel; and the positioning columns are inserted into bolt holes of the wheel. A lower pressure plate is fixed on the base, and limiting columns and an upper pressure plate are installed on the lower pressure plate, with steel balls and rubber strip being enclosed in a space formed by the lower pressure plate and the upper pressure plate. The fixture meets the requirement for machining the wheel outer rim without trace, has the characteristics of simple structure, convenient manufacture, stable performance and precision, and meets the requirements of automatic production.

The present invention relates to a rotary cutting tool assembly comprising a toolholder which has a central tool holding receptacle, and a cutting tool which has a holding projection that can be detachably held in the tool holding receptacle and via which the cutting tool is secured to and radially centered on the tool, wherein the holding projection has at its free end a pin-like, first centering section and an adjoining externally threaded section, wherein the holding projection ends in a radially outwardly projecting shoulder having an end face abutment surface, and the tool holding receptacle has an internally threaded section for receiving the externally threaded section and a first centering seat section which is positioned deeper within the tool holding receptacle and in which the centering section of the cutting tool is held.

The present invention relates to a rotary cutting tool assembly comprising a toolholder which has a central tool holding receptacle, and a cutting tool which has a holding projection that can be detachably held in the tool holding receptacle and via which the cutting tool is secured to and radially centered on the tool, wherein the holding projection has at its free end a pin-like, first centering section and an adjoining externally threaded section, wherein the holding projection ends in a radially outwardly projecting shoulder having an end face abutment surface, and the tool holding receptacle has an internally threaded section for receiving the externally threaded section and a first centering seat section which is positioned deeper within the tool holding receptacle and in which the centering section of the cutting tool is held.

Holder for a rotary tool which holder is formed with a holder body comprising a rear drive end and a front connection end having a connection thread for the connection of the tool. The holder comprises a thrust collar having a flat contact surface facing a connection end of the holder. The holder comprises an axially movable operating means, a number of restraint elements placed in one or more spaces in the holder body which restraint elements in a first axial position of the operating means are prevented from radial movement in said spaces and which restraint elements in a second axial position of the operating means allow radial movement in said spaces. Each one of said spaces for the restraint elements is limited in the axial direction by a front limiting wall and a rear limiting wall, which two limiting walls are parts of the holder body.