The present disclosure provides a worm gear machine, including a workbench, a cutter holder and a cutter holder adjusting system, where the cutter holder includes a big bracket, a first slide rail is disposed on the big bracket, a slide seat in sliding fit with the first slide rail is disposed on the first slide rail, a second slide rail is disposed on the slide seat, a small bracket in sliding fit with the second slide rail is disposed on the second slide rail; and a cutter holder spindle is disposed between the big bracket and the slide seat, a cutter bar synchronously rotating with the cutter holder spindle is disposed between an end of the cutter holder spindle facing toward the small bracket and the small bracket, and a gearbox for driving the cutter spindle to rotate is disposed in the big bracket.

Provided is a main spindle mechanism for a machine tool such that even in the case of a small-diameter spindle, it is possible to increase the torque transmitted to a large cutter and it is possible to prevent contact to and collisions with the workpiece. The main spindle mechanism, which is provided to a machine tool that cuts a workpiece by means of a cutter, is characterized by having: a spindle that transmits torque from the drive power source of the machine tool and is formed with outer teeth at the outer periphery of the tip thereof; a large cutter arbor provided with a shaft for attaching the large cutter and a base at which outer teeth are formed having the same diameter as the outer teeth of the spindle; and a gear-coupling-shaped sleeve that is provided in a manner so as to cover the base of the large cutter arbor and the tip of the spindle, and at which are formed inner teeth that mesh with both the outer teeth of the spindle and the outer teeth of the large cutter arbor.

A hob cutter arrangement includes a tool body which has a continuous axial bore, conical bore sections forming both ends of the axial bore, an end shank body at each end of the tool body, and a conical section inserted into the conical bore section. Each end shank body has a radial flange which can be placed against an end face of the tool body and a shaft section on the side of the flange opposite the conical section for clamping in a machine tool. An axle connects the end shank bodies and clamps them together. The end shank bodies are provided with blind holes opening towards the axle and provided with threads to the axle. Elastic elements are clamped between a central section of the axle and a front side of the end shank body on both sides of the axle.

The present disclosure comprises a gear manufacturing machine comprising a workpiece holder and a tool holder, which can each be caused to rotate by means of a drive, wherein the tool holder is arranged on a machining head, which can be moved relative to the workpiece holder by one or a plurality of motion axes of the gear manufacturing machine for gear manufacturing machining a workpiece held in the workpiece holder by means of a tool held in the tool holder, the tool holder having a counterholder. According to the present disclosure the counterholder is movable by a motion axis from its working position to an inactive position and/or is arranged on the machining head of the gear manufacturing machine in a releasably connectable manner.

The main spindle unit has a main spindle, a front bearing, a rear bearing, a front case for covering the front bearing, and a rear case for covering the rear bearing. The front case has a front body part for holding the front bearing and a front flange part extending radially outward from the front body part. The rear case has a rear body part for holding the rear bearing and a rear flange part extending radially outward from the rear body part. A front mounted surface, which can be brought into contact with a first mounting surface of a unit support table, is formed on the front flange part so as to face the front side thereof. A rear mounted surface, which contacts a second mounting surface of the unit support table, is formed on the rear flange part so as to face the front side thereof.

The present disclosure comprises a gear manufacturing machine comprising a workpiece holder and a tool holder, which can each be caused to rotate by means of a drive, wherein the tool holder is arranged on a machining head, which can be moved relative to the workpiece holder by one or a plurality of motion axes of the gear manufacturing machine for gear manufacturing machining a workpiece held in the workpiece holder by means of a tool held in the tool holder, the tool holder having a counterholder. According to the present disclosure the counterholder is movable by a motion axis from its working position to an inactive position and/or is arranged on the machining head of the gear manufacturing machine in a releasably connectable manner.

A tool head for a machine tool, in particular for a gear cutting machine, has a first and a second spindle unit each having at least one spindle bearing and a spindle shaft which is rotatably mounted in the respective spindle bearing about a tool spindle axis. The respective spindle bearing can support both radial and axial forces. The spindle units are arranged coaxially to each other, and a tool is received axially between the spindle shafts. A controlled clamping device connects the spindle bearings together. A control device activates the clamping device during a machining operation and deactivates it during machining pauses. Alternatively or additionally, the tool head has an axial force element that generates an axial preload force between the spindle bearings.

A tool changer is used for changing tools in a machine tool. The tool changer has a support structure on which a lifting carriage is guided along a vertical lifting direction. A pivot arm is pivotably mounted to the lifting carriage about a vertical pivot axis. A plurality of tool holders arranged vertically one above the other form a tool magazine. A tool gripper is attached to the pivot arm. The tool gripper grips a tool. The tool is subsequently moved between one of the tool holders and the tool spindle of the machine tool by a combined lifting and pivoting movement of the pivot arm. Optionally, an auxiliary arm pivotably attached to the pivot arm can be used to change a workpiece clamping means of the machine tool.

A method for producing a toothed workpiece gear, wherein the workpiece gear is clamped or fastened to a workpiece spindle, and a cutting tool having cutting teeth is clamped or fastened to a tool spindle. The tool spindle and the workpiece spindle are rotationally driven at a coupling ratio of the angles of rotation thereof having a periodic non-linearity or an axial distance from each other that changes periodically. The cutting teeth machine forms left and right tooth flanks of the teeth of the workpiece gear using left and right cutting edges in a chip-removing manner. A radial run-out error or a pitch error of the cutting tool is determined. The flank line shape errors of the right and left tooth flank resulting from the radial run-out error or the pitch error are reduced by the periodic non-linearity of the coupling ratio or the periodic change in the axial distance.

The main spindle unit has a main spindle, a front bearing, a rear bearing, a front case for covering the front bearing, and a rear case for covering the rear bearing. The front case has a front body part for holding the front bearing and a front flange part extending radially outward from the front body part. The rear case has a rear body part for holding the rear bearing and a rear flange part extending radially outward from the rear body part. A front mounted surface, which can be brought into contact with a first mounting surface of a unit support table, is formed on the front flange part so as to face the front side thereof. A rear mounted surface, which contacts a second mounting surface of the unit support table, is formed on the rear flange part so as to face the front side thereof.