Mounting flange for a tool body

Description

TECHNICAL AREA

[0001] The present invention relates to a receiving flange for a tool body, in particular for a grinding wheel. The invention further relates to a machining tool comprising such a receiving flange, and to a tool head equipped therewith. STATE OF THE ART

[0002] Mounting flanges for grinding wheels are standardized in DIN ISO 666:2013-12. According to this standard, a "hub flange" is a system consisting of a "fixed flange" and a "loose flange" for the frictional mounting of grinding wheels onto a grinding spindle. The loose flange is also referred to as the "counter flange." The clamping force for the frictional mounting of the grinding wheel is applied by several screws arranged on a pitch circle, which press the counter flange towards the fixed flange. The fixed flange incorporates a receptacle for a frictional or positive-locking connection with the grinding spindle. This interface between the hub flange and the grinding spindle is called the "flange socket."The part of the grinding spindle that interacts with this, through which the connection to the mounting flange is made, i.e. the interface of the grinding spindle to the mounting flange, is called the "spindle socket".

[0003] The Fig. 1 Figure 1 shows a central longitudinal section of a grinding tool 100 comprising a mounting flange 101 according to the prior art, with a grinding wheel 130 clamped therein. Such a mounting flange is offered by Reishauer AG, Wallisellen, Switzerland, under the designation "B 160".

[0004] The mounting flange 101 comprises a fixed flange 110 and a mating flange 120. The fixed flange 110 has a flange receptacle 111 for connection to a grinding spindle. In operation, the grinding spindle is on the right side of the Fig. 1The fixed flange 110 has a cylindrical outer surface 112, which is bounded on the spindle side by a collar 113. At the end facing away from the spindle, the fixed flange 110 has a connection area 115 with a reduced diameter and a cylindrical outer contour.

[0005] The mating flange 120 is annular in shape, with a cylindrical inner surface. This inner surface is pushed onto the cylindrical connection area 115 of the fixed flange 110. A cylindrical plug connection thus exists between the fixed flange 110 and the mating flange 120. The mating flange 120 has a cylindrical outer surface 122, the outer diameter of which corresponds to the outer diameter of the cylindrical outer surface 112 of the fixed flange. The outer surface 122 of the mating flange 120 is flush with the outer surface 112 of the fixed flange 110. A collar 123 is formed at the end of the mating flange 120 facing away from the spindle, which delimits the outer surface 122 of the mating flange 120 towards this end. The counter flange 120 is fixed to the fixed flange 110 with a ring of socket head cap screws 125.

[0006] The grinding wheel 130 is mounted with its central bore on the outer cylindrical surface 112 of the fixed flange 110 and the outer cylindrical surface 122 of the counter flange 120. Axially, the grinding wheel 130 is clamped between an annular first clamping surface 114 on the collar 113 of the fixed flange 110 and an annular second clamping surface 124 on the collar 123 of the counter flange 120. Optionally, thin intermediate washers can be inserted between the grinding wheel 130 and the clamping surfaces 114 and 124, respectively. The clamping force is generated by the socket head cap screws 125, which connect the counter flange 120 to the fixed flange 110. This creates a frictional connection between the grinding wheel 130 and the respective collar 113 and 123 at the clamping surfaces 114 and 124, optionally mediated by the intermediate washers.

[0007] In gear manufacturing, machining tools with small diameters are increasingly being used. To achieve the desired cutting speed, such tools are usually operated at relatively high speeds. These tools can be relatively long compared to their diameter. This makes them particularly susceptible to bending and torsional vibrations. A state-of-the-art mounting flange, as used in the Fig. 1 However, the arrangement shown is not ideally suited for a long and relatively thin tool. This is especially true if the tool is to be connected to spindle shafts at both ends. Document DE4309321 A1 forms the basis for the preamble of claim 1 and discloses an arrangement for the centered and axially fixed mounting of a rotating body, in particular a grinding wheel or a high-speed grinding wheel. PRESENTATION OF THE INVENTION

[0008] It is an object of the present invention to provide a receiving flange which is particularly suitable for receiving tool bodies which have a relatively small diameter in relation to their length.

[0009] This problem is solved by a receiving flange according to claim 1. Further embodiments are specified in the dependent claims.

[0010] A mounting flange for a tool body is proposed. The mounting flange defines a tool axis. It has a fixed flange designed to receive the tool body. A first flange receptacle for connection to a first spindle shaft rotatable about the tool axis is formed on the fixed flange. The mounting flange also has a mating flange that is detachably connected to the fixed flange. The fixed flange and the mating flange are connected to each other via a conical connection, the conical connection being arranged coaxially with the tool axis and formed by an inner cone ("taper receptacle") and an outer cone ("taper") received within the inner cone.

[0011] In this document, terms are used in accordance with the definitions in DIN ISO 666:2013-12 given above, with the following exceptions: The term "mounting flange" is also used for tool holders on which a tool body other than a grinding wheel is clamped. The term "counter flange" is understood more broadly than in DIN ISO 666:2013-12. It also includes structures that are detachably connected to the fixed flange to form a single unit, without the tool body being directly clamped between the fixed flange and the counter flange.

[0012] Unlike the standard in DIN ISO 666:2013-12, the mounting flange can be designed to be connected to a spindle shaft at each end. For this purpose, the mating flange can have a second flange receptacle for connection to a second spindle shaft. Since the mating flange is detachable from the fixed flange to allow for tool body changes, the diameter of the second flange receptacle can be largely freely selected and, in particular, can be larger than the inner diameter of the tool body bore if required. In this way, even with tools that have a small bore diameter, the second flange receptacle can be designed to be sufficiently large to transmit adequate torque.

[0013] By forming a conical connection between the fixed flange and the mating flange, a precisely centered connection is created that is both backlash-free and exceptionally rigid. This differs from a prior art receiving flange, as described in the Fig. 1 As illustrated, the frictional connection between the fixed flange and the mating flange is no longer achieved solely via the tool body clamped between them, but rather the frictional connection can occur directly between the fixed flange and the mating flange in the area of ​​the conical joint. In particular, it becomes possible to design the receiving flange in such a way that the clamping force with which the tool body is held on the receiving flange becomes largely independent of the force with which the fixed flange and the mating flange are axially pressed together at the conical joint.

[0014] This is particularly advantageous when the tool is connected to spindle shafts on both sides and the mounting flange is axially clamped between the two spindle shafts, so that an axial compressive force acts on the mounting flange on both sides. Whereas with a prior art mounting flange, as described in the Fig. 1 As shown, such a pressure force would be transferred to the tool body and could lead to damage to the tool body. In the present invention, the pressure force is transferred directly at the conical connection between the fixed flange and the counter flange and can thus be decoupled from the tool body.

[0015] Furthermore, the proposed design allows significantly higher torques to be transmitted between the fixed flange and the counter flange than is possible with the prior art. Fig. 1This is possible. This has particular advantages, for example, when the mounting flange is to be driven from both sides. If, for instance, the two drives generate different torques, the direct coupling between the fixed flange and the mating flange at the conical connection prevents the torque difference from being transmitted to the tool body.

[0016] The inner cone of the conical connection can be formed on the fixed flange and the outer cone on the mating flange. Alternatively, the inner cone can be formed on the mating flange and the outer cone on the fixed flange. The half-opening angle of the conical connection, i.e., the simple cone angle of the cone surfaces relative to the tool axis, can be, for example, 1° to 30°, preferably 2° to 10°. The length of the conical connection, when projected onto the tool axis, can be very short, but should preferably be at least 3 mm.

[0017] According to the invention, the connection between the fixed flange and the mating flange is a conical connection with axial face contact. A significant advantage of the conical connection with axial face contact is that the two parts (fixed flange and mating flange, including the flange receptacles formed thereon for connection to the respective spindle shaft) are not only precisely centered but also precisely positioned axially relative to each other. This allows these two parts to be reconnected with the same precision when changing grinding wheels, during which the two parts must be separated. The connection between the flange and mating flange therefore plays a crucial role in quality assurance during the manufacturing of the receptacle flange. Furthermore, the additional axial face contact allows for a higher axial force to act between the fixed flange and the mating flange than in a simple conical connection.This allows a higher torque to be transmitted between these elements. Furthermore, this can further improve torsional and bending stiffness.

[0018] For axial planar contact, a first axial planar contact surface is formed on the component (fixed flange or counter flange) on which the inner cone is formed, adjacent to the inner cone. On the component on which the outer cone is formed, a second axial planar contact surface, oriented opposite to the first planar contact surface, is formed adjacent to the outer cone. The fixed flange and the counter flange are frictionally pressed together at the first and second axial planar contact surfaces. It is advantageous if the first and second axial planar contact surfaces are arranged adjacent to the respective cone. In particular, the first planar contact surface is preferably arranged in a region adjacent to the end face of the inner cone and radially surrounding the end face of the inner cone. Similarly, the second planar contact surface is preferably arranged in a region radially surrounding the outer cone.Radially between the end face of the inner cone and the first flat contact surface, a weakening can be introduced into the material of the component in question (fixed flange or counter flange) in order to increase the radial extensibility of the inner cone.

[0019] To fix the counter flange to the fixed flange, axially aligned screws are advantageously provided. These press the fixed flange and the counter flange axially against each other in such a way that an axial pressing force acts between the fixed flange and the counter flange. The screws are advantageously distributed evenly around the tool axis to minimize imbalance.

[0020] To clamp the tool body axially in the mounting flange, the mounting flange preferably defines a first and second clamping surface facing each other, so that the tool body can be clamped axially under pressure between the first and second clamping surfaces. The clamping surfaces preferably run orthogonally to the tool axis. The tool body is not necessarily clamped directly between the first and second clamping surfaces. For example, an intermediate washer can be inserted between the respective clamping surface and the tool body. This washer can be made of aluminum, for example, and can be very thin, for example, less than 1 mm thick.

[0021] In particular, the receiving flange can have a positioning ring that has an axially variable position relative to the mating flange, with the first clamping surface being formed on the fixed flange and the second clamping surface being formed on the positioning ring. This makes it possible to clamp tool bodies of different widths in the receiving flange, even though the relative position of the fixed flange and the mating flange is determined by the conical connection and the face contact.

[0022] To change the axial position of the positioning ring, the fixed flange, or preferably the mating flange, can have an external thread, and the positioning ring can have a complementary internal thread. The axial position of the positioning ring can be adjusted by screwing it. Locking elements, such as radial locking pins, can be attached to or within the positioning ring to prevent unintentional rotation of the positioning ring in a locked position. An intermediate ring can be arranged axially adjacent to the positioning ring to transfer an axial clamping force from the positioning ring to the tool body. The intermediate ring then provides a sliding surface for the clamping surface of the positioning ring without rotating itself. The intermediate ring prevents direct friction between the positioning ring and the tool body during screwing.In order to generate a defined clamping force on the tool body even when the length of the tool body changes, e.g. due to setting processes, the intermediate ring can have elastic properties.

[0023] In alternative embodiments, the positioning ring can be axially displaceable relative to the fixed flange and / or the mating flange, and threaded elements can be provided that are screwed into the mating flange or into the positioning ring to change the axial position of the positioning ring relative to the mating flange. These threaded elements can be, for example, screws whose axial position relative to the mating flange is fixed and which can be screwed into or out of the positioning ring to varying degrees in order to change its axial position. Alternatively, the threaded elements can be set screws that can be screwed into and out of the mating flange to varying degrees and which exert an axial compressive force on the positioning ring at their distal end.To generate a defined clamping force on the tool body even when its length changes, the screw connection can be combined with a spring element. For example, axially spring-loaded elements, such as bushings with disc springs, can be provided in the positioning ring, against which the aforementioned threaded studs exert axial pressure.

[0024] The connection between the mounting flange and the spindle shafts is also preferably made via tapered connections, preferably with a flat contact surface. This allows for very precise centering of the mounting flange in the grinding head. For example, the connection can be made via one of the designs A, BF, BM, CF, or CM specified in DIN ISO 666:2013-12. The first and / or second flange mounting can be designed as an internal or external cone with a flat contact surface. However, alternative connection methods between the mounting flange and the spindle shafts are also conceivable, e.g., via radially acting hydraulic expansion elements.

[0025] It is advantageous if the two flange mounts are designed differently in such a way that the tool can only be inserted in a predetermined position between the spindle shafts. For example, the diameters of the two flange mounts can be different.

[0026] The present invention further provides a machining tool comprising a mounting flange according to one of the appended claims and a tool body clamped on the mounting flange. While the mounting flange is particularly well suited, due to its design, for long tool bodies with a relatively small diameter (e.g., a length-to-diameter ratio greater than 1), the invention is not limited to such tool bodies. The tool body can therefore have any length-to-diameter ratio. The machining tool can, in particular, be a grinding tool, especially a tool for gear grinding. Accordingly, the tool body can be a one-piece or multi-piece grinding element. The grinding element can, in particular, be ceramic-bonded and thus dressable. It can, for example, contain abrasive grains made of corundum or cubic boron nitride (cBN).The grinding element can, for example, also be polymer-bonded and specifically designed as a grinding element for polishing. Alternatively or additionally, the tool body can, for example, have a metallic base body with a non-dressable hard coating. Any combination of similar or different tool bodies is also conceivable. The tool body can, in particular, comprise a grinding wheel with a helically profiled outer contour (grinding worm) and / or a profile grinding wheel. In the case of a multi-part tool body, the tool body can, in particular, be a combination of two or more grinding worms, for example, a roughing grinding worm with a finishing or polishing grinding worm, a combination of a grinding worm with a profile grinding wheel, or a combination of two or more profile grinding wheels.

[0027] The present invention also provides a tool head for a machine tool, in particular for a gear cutting machine. The tool head comprises a machining tool of the type mentioned above. It further comprises a first spindle unit with a first spindle shaft rotatably mounted in the first spindle unit about the tool axis, and a second spindle unit with a second spindle shaft rotatably mounted in the second spindle unit about the tool axis. The first spindle unit and the second spindle unit are arranged coaxially to each other such that the machining tool is received axially between the first spindle shaft and the second spindle shaft.In order to accommodate the tool between the spindle shafts and to be able to transmit a torque to the tool, it is advantageous if a spindle nose is designed on the first and / or second spindle shaft in such a way that a force-fit and / or form-fit connection to the tool can be established at the spindle nose in question by an axial compressive force acting between the tool and the spindle nose, in particular via the aforementioned conical connection.

[0028] In some embodiments, the first spindle unit and the second spindle unit are housed in a common spindle housing. The second spindle bearing can then be held in a bearing receptacle that is axially displaceable relative to the common spindle housing to allow for tool changes. In other embodiments, the two spindle units are housed in separate spindle housings, which are displaceable relative to each other along the workpiece axis to allow for tool changes.

[0029] Particular advantages arise when the two spindle shafts are axially clamped to the machining tool, so that an axial compressive force acts on the machining tool from both sides. The following design is particularly advantageous for this purpose: The second spindle shaft has at least one axial bore. The tool head accordingly has at least one drawbar extending through the corresponding axial bore of the second spindle shaft, the drawbar being connectable to the first spindle shaft at one end. The drawbar is connectable to the second spindle shaft at its other end in such a way that an axial compressive force can be generated between the first and second spindle shafts and applied to the tool.For this purpose, the machining tool, specifically its receiving flange, also has at least one axial bore, so that the respective drawbar can be passed through the corresponding bore of the machining tool.

[0030] This type of axial clamping creates a unit consisting of the two spindle shafts and the machining tool that is exceptionally torsionally and flexurally rigid. The combination of tie rod and clamping element enables a high axial compressive force between the machining tool and the two spindle shafts. As a result, the unit acts like a single shaft. At the same time, this design can be very compact. This makes it particularly suitable for tools with a small diameter. Thanks to the direct connection of the fixed flange to the mating flange at the conical joint, the high axial compressive force is not, or only minimally, transmitted to the tool body.

[0031] The aforementioned design with a drawbar is also advantageous if the tool is designed differently than as discussed above. In this respect, the present disclosure also relates to a tool head for a machine tool that is not part of the invention as defined in the claims, in particular for a gear cutting machine, comprising: a first spindle unit with a first spindle shaft which is rotatably mounted in the first spindle unit about a tool spindle axis;and a second spindle unit with a second spindle shaft rotatably mounted in the second spindle unit about the tool spindle axis, wherein the first spindle unit and the second spindle unit are arranged such that a tool can be received axially between the first spindle shaft and the second spindle shaft in order to drive the tool to rotate about the tool spindle axis, wherein the second spindle shaft has at least one axial bore, wherein the tool head has at least one drawbar extending through the axial bore of the second spindle shaft, wherein the drawbar can be connected to the first spindle shaft at one end in a tensile manner, and wherein the drawbar can be connected to the second spindle shaft at its other end in such a way that an axial compressive force can be generated on the tool between the first spindle shaft and the second spindle shaft.

[0032] Preferably, exactly one tie rod is provided, extending through a central axial bore in the second spindle shaft. Accordingly, it is preferred if the receiving flange also has a central axial bore through which the tie rod can be guided.

[0033] In a particularly simple design, the drawbar can be connected to the first spindle shaft by screwing it axially into the first spindle shaft. For this purpose, complementary threads can be formed at the corresponding end of the drawbar and on the first spindle shaft. However, other connection types are also conceivable, e.g., a bayonet-type connection.

[0034] The tie rod can advantageously be provided at its other, free end with a clamping element that forms an annular bearing surface, wherein the annular bearing surface rests against the second spindle shaft after the connection of the tie rods with the first spindle shaft and generates an axial compressive force on the second spindle shaft in order to push it in the direction of the first spindle shaft.

[0035] In the simplest case, the tie rod can be designed, for example, as a screw with a screw head. The screw can then be screwed into the first spindle shaft, and the screw head can form the clamping element. The axial clamping force is then simply generated by tightening the screw.

[0036] In another, equally simple embodiment, the drawbar is provided with an external thread at its free end, onto which a nut can be screwed. In this case, the nut forms the clamping element, and the axial clamping force is generated simply by tightening the nut.

[0037] Preferably, the tool head has a clamping element that can be detachably connected to the drawbar and generates a clamping force that preferably acts purely axially, without tightening the clamping element producing a torque component about the tool spindle axis. The clamping element has a base element that can be rigidly connected to the drawbar, for example, via a screw connection, a bayonet fitting, or a clamping sleeve. The base element can have a central receiving opening to accommodate the drawbar or (if sufficient space is available) a pin that can be fixed in an axial bore of the drawbar. The clamping element also has an axial pressure element that is axially movable, and in particular axially displaceable, relative to the base element in the direction of the second spindle shaft, in order to press the second spindle shaft axially in the direction of the first spindle shaft.The axial pressure element can be, in particular, ring-shaped and surround the central receiving opening or the pin of the base element; in this case, the axial pressure element can also be referred to as a "pressure ring." The axial pressure element forms the aforementioned ring-shaped contact surface. The clamping element also has at least one actuating element, wherein the actuating element is movable relative to the base element in order to move the axial pressure element axially relative to the base element. For example, a pressure screw that can be screwed into the base element along a longitudinal or transverse direction can serve as the actuating element. Such clamping elements are known from the prior art and are commercially available in many variations.

[0038] In some embodiments, the force transmission from the actuating element to the axial pressure element is purely mechanical. For example, several socket head cap screws, held axially on the base element and screwed into the axial pressure element to displace it axially relative to the base element, can serve as actuating elements. In other embodiments, one or more threaded pins, adjustable in the base element via a threaded connection in the direction of the axial pressure element, serve as actuating elements. In still other embodiments, the actuating element acts, for example, on a gearbox that advances the axial pressure element. Such clamping elements are available, for example, under the designations ESB, ESG, or ESD from Enemac GmbH, Kleinwallstadt, Germany.

[0039] In other embodiments, the force transmission from the actuating element to the axial pressure element is hydraulic. For this purpose, the actuating element can, for example, be designed as a pressure screw which, when screwed in, generates pressure in a hydraulic system, with this pressure acting on the axial pressure element. Such clamping elements are available, for example, from Albert Schrem Werkzeugfabrik GmbH, Herbrechtingen, Germany.

[0040] Instead of generating the axial compressive force between the drawbar and the second spindle shaft with a clamping element that remains on the drawbar during operation, it is also conceivable to first generate the compressive force with a clamping tool, fix the connection in the clamped state with a simple nut, and then remove the clamping tool.

[0041] The tool can also be clamped in a manner other than with a continuous drawbar between the first and second spindle shafts, creating a tightly clamped unit consisting of the two spindle shafts and the tool. For example, embodiments are conceivable in which a first drawbar can be connected to the tool at one end, for instance, by screwing it to the tool or connecting it via a hollow taper shank. The first drawbar can then extend through an axial bore in the first spindle shaft and be connected to the first spindle shaft at its other end in such a way that an axial compressive force can be generated between the first spindle shaft and the tool. A second drawbar can be arranged on the opposite side of the tool.This second drawbar can, in turn, be connected to the tool at one end, for example, by screwing it to the tool or connecting it via a hollow taper shank. The second drawbar can then extend through an axial bore in the second spindle shaft and be connected to the second spindle shaft at its other end in such a way that an axial compressive force can be generated between the second spindle shaft and the tool.

[0042] As an alternative to axial clamping with a tie rod, the mounting flange can also be connected to at least one spindle shaft in another way. In particular, the mounting flange can be equipped with at least one thread, preferably a threaded bore, to connect the at least one spindle shaft to the mounting flange.

[0043] To facilitate tool changes, it is advantageous if the second spindle unit is axially displaceable relative to the first spindle unit. If both spindle units are housed in a common spindle casing, this can be achieved by making the spindle bearings for the second spindle shaft axially displaceable relative to this spindle casing.

[0044] The first and / or second spindle unit can have a drive motor configured to rotate the corresponding spindle shaft about the tool spindle axis, thereby driving the tool. In some embodiments, only the first spindle unit has a drive motor, and the second spindle unit acts as a passive counter spindle for the first spindle unit, without its own drive motor. In other embodiments, the second spindle unit also has its own drive motor. The respective drive motor can, in particular, be a direct drive.

[0045] The present disclosure also provides a machine tool, not part of the invention as defined in the claims, comprising a tool head of the aforementioned type and at least one workpiece spindle for driving a workpiece to rotate about a workpiece axis. The machine tool can be configured as a gear cutting machine, in particular as a gear grinding machine. For this purpose, the machine tool can have a machine control configured (in particular programmed accordingly) to cause the machine to machine the gear teeth of a workpiece mounted on the at least one workpiece spindle with the tool. In particular, the machine control can be configured to cause the machine to machine the gear teeth of the workpiece by profile grinding or generating grinding.For this purpose, the machine control can be designed to establish a suitable rolling coupling between the workpiece spindle and the tool spindle. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Preferred embodiments of the invention are described below with reference to the drawings, which serve only for illustration and are not to be interpreted restrictively. The drawings show: Fig. 1 a grinding tool comprising a receiving flange according to the prior art, in a central longitudinal section; Fig. 2 a grinding tool comprising a receiving flange according to a first embodiment of the present invention, in a perspective view; Fig. 3 the grinding tool of the Fig. 2 in a central longitudinal section; Fig. 4 the mounting flange of the grinding tool of the Fig. 2 in a perspective view; Fig. 5 an enlarged detail of the receiving flange of the Fig. 4in a central longitudinal section in the plane VV of the Fig. 6 ; Fig. 6 the receiving flange of the Fig. 4 in a front view of the mating flange; Fig. 7 a section of a central longitudinal section through a grinding tool with a receiving flange according to a second embodiment; Fig. 8 a section of a central longitudinal section through a grinding tool with a receiving flange according to a third embodiment; Fig. 9 a section of a central longitudinal section through a grinding tool with a receiving flange according to a fourth embodiment; Fig. 10 a tool head in a schematic perspective view; Fig. 11 the tool head of the Fig. 10 in a perspective sectional view; Fig. 12 a clamping nut in a central longitudinal section; Fig. 13 the clamping nut of the Fig. 13in a perspective view; and Fig. 14 a machine tool for hard finishing of gears by gear grinding in a schematic perspective view. DESCRIPTION OF PREFERRED EXECUTION FORMS Definitions

[0047] Gear cutting machine: A gear cutting machine is a machine designed for producing or machining gear teeth on workpieces, particularly internal or external gear teeth on gears. For example, it could be a finishing machine used to machine pre-cut teeth, or in particular a hard finishing machine used to machine pre-cut teeth after hardening. A gear cutting machine has a machine control system programmed to automatically control the machining of the gear teeth.

[0048] Gear machining:A type of gear machining in which a tool rolls on a workpiece, generating a cutting motion. Various gear machining processes are known, distinguished between processes with geometrically undefined cutting edges, such as gear grinding or gear honing, and processes with geometrically defined cutting edges, such as gear milling, gear skiving, gear scraping, or gear shaping.

[0049] Gear grinding:The gear grinding process is a continuous machining process with a geometrically undefined cutting edge for producing axially symmetrical periodic structures. A grinding wheel with a helically profiled outer contour ("grinding worm") is used as the tool. The tool and workpiece are mounted on rotary spindles. The characteristic rolling motion of the process is achieved by coupling the rotary movements of the tool and workpiece around their axes. This rolling motion, combined with an axial feed motion of the tool or workpiece along the workpiece axis, generates a cutting motion.

[0050] Tool head:In this document, a "tool head" refers to an assembly designed to hold a machining tool and drive it to rotate. The tool head may be mounted on a swivel body and / or one or more slides to align and position the tool relative to a workpiece.

[0051] Spindle unit:In machine tool manufacturing, a rotatable shaft on which a tool or workpiece can be clamped is usually referred to as a "spindle." However, the term "spindle" is also frequently used to describe an assembly that includes not only the rotatable shaft but also the associated spindle bearings for its rotation and the associated housing. In this document, the term "spindle" is used in this sense. The shaft alone is referred to as a "spindle shaft." An assembly that includes at least the associated spindle bearings is referred to as a "spindle unit." A "spindle unit" can have its own housing, or it can be housed together with another spindle unit in a common housing. Mounting flange according to the first embodiment

[0052] In the Figures 2 and 3A machining tool 100 is shown. The machining tool 100 comprises a mounting flange 101 in which a tool body 130 is clamped. The mounting flange 101 is in the Figures 4 to 6 Shown alone. Functionally similar parts are shown with the same reference symbols as in the Fig. 1 provided.

[0053] In this example, the tool body 130 is a grinding tool. Therefore, the machining tool 100 in this example is a grinding tool. However, other types of tool bodies 130 may also be used.

[0054] The mounting flange 101 defines a tool axis B about which it can rotate. It comprises a fixed flange 110 and a mating flange 120. The fixed flange 110 has a Fig. 3At the right-hand end, a first flange receptacle 111 is provided for connection to a first spindle shaft. In this example, the first flange receptacle 111 is designed as an internal cone ("taper receptacle") with a flat contact surface arranged within the internal cone, specifically as a short taper receptacle 1:4 according to DIN ISO 702-1:2010-04. The fixed flange 110 has a cylindrical outer surface 112. The outer surface 112 is bounded at the end of the fixed flange 110 where the first flange receptacle 111 is formed by a collar 113. The collar 113 has an enlarged outer diameter. It forms an annular first clamping surface 114 for the tool body 130. The first clamping surface 114 extends in a plane that is orthogonal to the tool axis B. A central bore 116 extends along the tool axis B through the fixed flange 110.Positioning bores 117 serve to position and fix the fixed flange 110 in the circumferential direction during the clamping of the tool body 130.

[0055] A machine-readable data carrier, e.g., an RFID tag or an optical code, can be attached to a receiving notch 118 on the outer circumference. Balancing holes 119 are used for balancing and / or allow the attachment of additional balancing weights. On its in the Fig. 3 At the left end, i.e., at the end facing away from the first flange receptacle 111, a further internal cone ("conical receptacle") 151 is formed on the fixed flange 110. This is located in the Fig. 5 particularly clearly visible. The area of ​​the end face of the fixed flange 110 adjacent to and surrounding the inner cone 151 forms a first flat contact surface 153. The first flat contact surface 153 extends orthogonally to the tool axis B.

[0056] The counter flange 120 has on its in the Fig. 3 At the left end, i.e., at the end facing away from the first flange receptacle 111, a second flange receptacle 121 is located. The second flange receptacle 121 is also designed as an internal cone ("taper receptacle") with a flat bearing surface arranged within the internal cone, specifically as a short taper receptacle 1:4 according to DIN ISO 702-1:2010-04. At its Fig. 3 At the right-hand end, i.e., at its end pointing towards the fixed flange 110, an outer cone ("cone") 152 is formed on the mating flange 120, which is complementary to the inner cone ("cone receptacle") 151 on the fixed flange 110. The outer cone 152 is radially separated from an annular second planar contact surface 154 (see Fig. 6) surrounding the first flat contact surface 153 on the fixed flange. A central bore 126 extends along the tool axis B through the counter flange 120. The bore 126 is aligned with the bore 116 of the fixed flange 110. The bores 116 and 126 together form a continuous axial bore through the receiving flange 101.

[0057] The mating flange 120 is connected to the fixed flange 110 via a conical connection with face contact. The conical connection 150 is formed by the inner cone 151 on the fixed flange 110 and the complementary outer cone 152 on the mating flange 120. Face contact occurs on the two complementary face contact surfaces 153, 154.

[0058] A key advantage of this design is that, especially with small grinding wheels, this division of the mounting flange allows for significantly larger diameters of the flange mounts 111 and 121 on both sides for torque transmission than would be possible if both flange mounts were attached to the fixed flange. However, since any separation also has disadvantages, a connection with high rigidity is required. This is ensured by the tapered connection with face contact. Additionally, this type of connection ensures that the fixed flange 110 and the counter flange 120 fit perfectly again after each grinding wheel change and can be easily separated.

[0059] The counter flange 120 is fixed to the fixed flange 110 by several socket head cap screws 125 evenly distributed around the circumference. The socket head cap screws 125 generate a defined axial clamping force between the fixed flange 110 and the counter flange 120. This axial clamping force is transmitted directly via the tapered connection with face contact between the fixed flange 110 and the counter flange 120.

[0060] An external thread 127 is formed on an outer cylindrical surface of the mating flange 120. A positioning ring 140 is screwed onto the external thread 127. To allow the positioning ring 140 to be rotated with a suitable wrench, several longitudinal grooves 141 are formed on the outer circumference of the positioning ring 140. The positioning ring 140 can be fixed to the mating flange 120 with radial locking pins 142 to prevent unintentional rotation of the positioning ring 140. The positioning ring 140 forms a second clamping surface 144 on its end face facing the fixed flange 110. The second clamping surface 144 extends in a plane that is perpendicular to the tool axis B. It points in the direction of the first clamping surface 114 on the fixed flange 110.

[0061] The tool body 130 has a central bore along the tool axis B. The tool body 130 is pushed onto the fixed flange 110 with this bore. In the area of ​​its bore, its inner surface rests against the outer surface 112 of the fixed flange 110. The tool body 130 is axially supported on the first clamping surface 114 of the fixed flange 110. A thin intermediate washer 131, which may be made of aluminum, for example, can be provided between the tool body 130 and the first clamping surface 114. The tool body 130 is fixed to the receiving flange 101 by means of the positioning ring 140 and an intermediate ring 145. Here, too, a thin intermediate washer 132, which may again be made of aluminum, can be provided between the tool body and the intermediate ring 145.The positioning ring 140, with its second clamping surface 144, exerts an axial clamping force on the tool body 130 via the intermediate ring 145 and, if applicable, the intermediate washer 132. This axial clamping force can be adjusted independently of the axial contact force between the fixed flange 110 and the counter flange 120 by appropriately positioning the positioning ring 140.

[0062] To clamp the tool body 130, proceed as follows. First, loosen the counter flange 120 from the fixed flange 110. Screw the positioning ring 140 back as far as possible towards the second flange receptacle 121, and slide the intermediate ring 145 back as far as possible. Slide the tool body 130 and, if applicable, the intermediate washers 131 and 132 onto the fixed flange 110, and secure the counter flange 120 to the fixed flange 110 with the screws 125. Tighten the screws 125 until sufficient axial clamping force is achieved between the fixed flange 110 and the counter flange 120. The tool body 130 is not yet axially clamped during this process. Only after the connection between the fixed flange 110 and the counter flange 120 has been established, is the positioning ring 140 screwed on until the desired axial clamping force acts on the tool body 130 via the intermediate ring 145.The axial clamping force on the tool body 130 is thereby set independently of the axial contact force between the fixed flange 110 and the counter flange 120.

[0063] The mounting flange 101 can be designed to allow the mounting of only a specific type of tool body 130. For example, depending on the type of tool body 130, different outer diameters of the outer cylindrical surface 112 can be provided. In particular, a larger outer diameter can be provided for grinding wheels with corundum abrasive grains than for grinding wheels with cBN abrasive grains. This reliably prevents a cBN grinding wheel from being mistakenly mounted on a mounting flange designed for a corundum grinding wheel, and vice versa. Instead of different diameters for different tool types, this can also be achieved by different shapes, e.g., by incorporating grooves, forming a polygonal area, or creating a toothed surface on the mounting flange.

[0064] To ensure that the two flange mounts 111, 121 are precisely aligned with each other, the fixed flange 110 and the counter flange 120 are manufactured in pairs, including balancing. Second to fourth embodiments

[0065] In the Fig. 7A second embodiment is illustrated. This differs from the first embodiment primarily in the manner in which the tool body 130 is clamped in the receiving flange 101. As in the first embodiment, a positioning ring 140 is provided for this purpose. This ring is axially displaceable relative to the counter flange 120. Several adjusting screws 146 in the form of socket head cap screws are screwed into the positioning ring 140. The adjusting screws 146 are arranged evenly distributed in the circumferential direction. They are axially supported on the counter flange 120, thus preventing axial movement towards the second flange receptacle 122. When the socket head cap screws 146 are unscrewed from the positioning ring 140, they press the positioning ring 140 axially against the tool body 130, thereby generating an axial clamping force.

[0066] In the Fig. 8A third embodiment is illustrated. This embodiment also differs from the first embodiment primarily in the way in which the tool body 130 is clamped in the receiving flange 101. Again, the positioning ring 140 is axially displaceable relative to the counter flange 120. This is achieved by positioning pins 147 in the form of threaded pins, which are guided in threads in the counter flange 120. When the positioning pins 147 are screwed into the counter flange, they press the positioning ring 140 axially against the tool body 130 to generate the axial clamping force.

[0067] In the Fig. 9A fourth embodiment is illustrated. This largely corresponds to the third embodiment. In contrast to the third embodiment, however, axial spring elements 148 in the form of spring bushings are arranged in the positioning ring 140. The positioning pins 147 act on these spring elements. Due to their elastic properties, the spring elements ensure that a sufficient axial clamping force is still exerted on the tool body 130 even if the length of the tool body 130 changes, e.g., due to settling processes in the tool body 130. Tool head with machining tool

[0068] In the Figures 10 and 11 A tool head with a machining tool 100 according to one of the embodiments discussed above is illustrated. For the sake of clarity, the machining tool 100 is shown only schematically.

[0069] The tool head comprises a base 310. A linear guide 311 is formed on the base 310. A first spindle unit 320 and a second spindle unit 330 are slidably guided on the linear guide 311 along a shift direction Y. For this purpose, the spindle units each have corresponding guide shoes 326, 336. The machining tool 100 is held between the spindle units 320, 330. The tool axis B runs parallel to the shift direction Y.

[0070] The second spindle unit 320 and the first spindle unit 330 can be coupled together after the machining tool 100 has been inserted between them. In the coupled state, they can be moved together along the shift direction Y by means of a shift drive (not shown) and a ball screw drive 312 in order to change the tool area that engages with a workpiece along the tool axis.

[0071] In this example, spindle unit 320 is a motor spindle with a drive motor 324 that drives a first spindle shaft 322 to rotate about the tool axis B. The first spindle shaft 322 is mounted in spindle bearings 323 in the spindle housing 321 of the first spindle unit 320. In this example, the second spindle unit 330 is a counter spindle with a non-driven second spindle shaft 332, which is mounted in spindle bearings 333 in the spindle housing 331 of the second spindle unit 330. However, both spindle units 320 and 330 can also be driven.

[0072] At the tool-side ends of the spindle shafts 322, 332, opposing spindle mounts in the form of spindle noses 325, 335 are formed. The shape of the spindle noses is complementary to the shape of the flange mounts 111, 121 of the mounting flange 101 of the machining tool 100. They each have a conical shape tapering towards the machining tool 100 and a flat contact surface on their respective end face. For example, each spindle nose can be designed as a 1:4 tapered shank according to DIN ISO 702-1:2010-04.

[0073] A conical connection with face contact exists between the flange mounts 111, 121 and the spindle noses 325, 335. The conical connections can have different diameters at the two ends of the machining tool 100 to ensure that the machining tool 100 can only be mounted in the correct orientation between the spindle noses 325, 335.

[0074] The machining tool 100 is axially clamped between the spindle noses 325 and 335 by a drawbar 370 and a clamping nut 372. For this purpose, the machining tool 100 and the second spindle shaft 332 each have a through central axial bore. The first spindle shaft 322 also has a central axial bore at its tool-side end. This bore has an internal thread. The drawbar 370 is inserted through the central bores of the spindle shaft 332 and the machining tool 100. At its end facing the first spindle unit 320, it has an external thread that is screwed into the internal thread of the first spindle shaft 322. At its other end, it also has an external thread. The clamping nut 372 is screwed onto this external thread. By tightening the clamping nut 372, the clamping nut 372 exerts an axial pressure on the second spindle shaft 332 in the direction of the machining tool 100.This axially clamps the machining tool 100 between the spindle noses 325 and 335. The result is a single, continuous shaft with high bending and torsional stiffness.

[0075] A first balancing unit 350 is arranged axially on the first spindle shaft 322 between the housing 321 of the first spindle unit 320 and the machining tool 100. A second balancing unit 360 is arranged axially on the second spindle shaft 332 between the housing 331 of the second spindle unit 330 and the machining tool 100. The balancing units 350 and 360 surround their respective spindle shafts 322 and 332 outside the housing of their respective spindle units 320 and 330. Each unit has a housing that tapers from the associated spindle unit towards the machining tool 100. The tapered outer contour of the balancing units 350 and 360 reduces the risk of collisions between the balancing devices and a workpiece. Each of the balancing units 350 and 360 is designed as a ring balancing system.The two balancing units 350, 360 serve to balance the system consisting of the machining tool 100 and the spindle shafts 322, 332 clamped to it in two balancing planes. Alternatively, it is conceivable to arrange at least one balancing element in the mounting flange. Tension nut

[0076] In the Figures 12 and 13 An example of a clamping nut 372 is illustrated, which is not part of the invention as defined in the claims, as it can be used in the tool head described above.

[0077] The clamping nut 372 has a base element 373 that defines a central bore with an internal thread for screwing the base element 373 onto a drawbar with a corresponding external thread. At one end, the base element 373 is externally shaped like a hexagonal nut. A support ring 374 is attached to the base element 373. This ring rests against a collar of the base element 373 in such a way that it prevents axial movement in one direction (in the Fig. 9 to the left) is prevented. Furthermore, an annular axial pressure element 375 is axially displaceable on the base element 373. Several actuating elements 376 in the form of pressure screws are screwed into the axial pressure element 375 and axially supported on the support ring 374 in such a way that they are prevented from moving along one direction (in the Fig. 9to the left) are prevented from axially moving. By unscrewing the pressure screws from the axial pressure element 375, the axial pressure element 375 is moved relative to the base element 373 along the direction opposite to the support direction (in Fig. 9 (to the right) advanced.

[0078] To clamp a tool 100 between the two spindle shafts 322, 332, the axial pressure element 375 is first moved fully back relative to the base element 373 by screwing the pressure screws into the axial pressure element 375 as far as possible. The clamping nut 372 is then screwed onto the drawbar 370 and positioned against the second spindle shaft 332 using the external hexagon on the base element 373. This is done with a relatively low torque. Subsequently, the annular axial pressure element 375 is advanced in a controlled manner towards the second spindle shaft 332 using the pressure screws until the desired clamping force is applied to the tool 340. The axial pressure element 375 rests against the second spindle shaft 332 with an annular contact surface.

[0079] Of course, other clamping nut designs known from the prior art can also be used. The force transmission can, for example, be achieved in a different way than shown. In particular, a hydraulic clamping nut can be used.

[0080] Instead of a clamping nut with internal thread, a clamping element can also be used which can be connected to the pull rod in a different way than via a screw connection, e.g. via a bayonet or via a clamping bushing. Construction of an exemplary machine tool

[0081] In the Fig. 14Figure 1 shows an example of a machine tool for the hard finishing of gears by gear grinding. The machine has a machine bed 600 on which a tool carrier 200 is slidably arranged along a horizontal feed direction X. A Z-slide 210 is slidably arranged on the tool carrier 200 along a vertical direction Z. The Z-slide 210 carries a swivel body 220, which is pivotable relative to the Z-slide 210 about a horizontal pivot axis A. The pivot axis A runs parallel to the feed direction X. The tool head 300, shown only symbolically, is arranged on the swivel body 220. The shift direction Y of the tool head 300 is perpendicular to the X-axis and at an angle to the Z-axis that is adjustable about the A-axis.

[0082] A swiveling workpiece carrier in the form of a rotary tower 400 is also arranged on the machine bed 600. The rotary tower 400 can be pivoted about a vertical pivot axis C3 between several rotational positions. It carries two workpiece spindles 500, on each of which a workpiece 510 can be clamped. Each of the workpiece spindles 500 can be driven to rotate about a workpiece axis. In the Fig. 12 The workpiece axis of the visible workpiece spindle 500 is designated C2. The workpiece axis of the in Fig. 12The workpiece spindle, which is not visible, is designated as the C1 axis. The two workpiece spindles are located on the rotary turret 400 in diametrically opposed positions (i.e., offset by 180° with respect to the swivel axis C3). In this way, one of the two workpiece spindles can be loaded and unloaded while a workpiece is being machined on the other workpiece spindle. This largely avoids undesirable non-productive time. Such a machine concept is known, for example, from WO 00 / 035621 A1.

[0083] The machine features a machine control system 700, represented only symbolically, which comprises several control modules 710 and an operator panel 720. Each of the control modules 710 controls a machine axis and / or receives signals from sensors. Variations

[0084] The interface between the spindle shafts 322, 332 and the machining tool 100 can also be designed differently than in the embodiments described above. In particular, a different type of conical connection can be used. Any known conical connections can be used, e.g., the types A, BF, BM, CF, or CM specified in DIN ISO 666:2013-12. For details, reference is made to DIN ISO 666:2013-12 and to the other standards mentioned therein: DIN EN ISO 1119:2012-04, DIN ISO 702-1:2010-04, ISO 12164-1:2001-12, and ISO 12164-2:2001-12.

[0085] Instead of using a machine-readable data carrier as described above, or in addition to it, the identification of the receiving flange or the tool formed by it can also be achieved in other ways, e.g., by mechanical coding. The coding can be done, for example, by one or more notches that allow for the unambiguous identification of at least the type of receiving flange.

[0086] The drawbar 370 can extend through the first spindle shaft 322 instead of through the second spindle shaft 332 and be connected to the second spindle shaft 332 at its end. The clamping element then exerts an axial force on the first spindle shaft in the direction of the second spindle shaft.

[0087] To clamp the machining tool 100 axially between the first spindle shaft 322 and the second spindle shaft 332, instead of a central tie rod or additionally, two or more tie rods can be used, which run parallel to each other and radially spaced from the tool spindle axis B and are arranged in different angular positions relative to the tool spindle axis B.

[0088] The fixing and axial clamping of the machining tool 100 between the first spindle shaft and the second spindle shaft under pressure can also be achieved in a manner other than with a continuous drawbar, for example with clamping systems arranged inside the respective spindle shaft. For this purpose, the connection between the machining tool and the spindle shafts can be made, for example, via hollow taper shanks (HSK) according to ISO 12164-1:2001-12 and ISO 12164-2:2001-12.

[0089] The tool body can be designed differently than in the embodiments described above. In particular, the tool body can also be multi-part.

[0090] The tool body can be dressable or non-dressable. A non-dressable tool body can, for example, have a metallic base with a hard coating applied to it. Such a tool body can, in principle, be mounted on the mounting flange in the same way as a dressable tool body. Alternatively, it is also conceivable to manufacture a one-piece tool whose outer contour in the area of ​​the connection points with the tool spindles is designed according to the flange mounts 111, 121, with the hard coating being an integral part of this one-piece tool. The tool can then be identified at the mounting flange using a machine-readable data carrier and / or by mechanical coding, just as described above. Such one-piece tools can be part of a tool assortment that includes both tools with the mounting flange described above and one-piece tools. REFERENCE MARK LIST

[0091] 100 Grinding tool 101 Mounting flange 110 Fixed flange 111 First flange mount 112 Outer surface 113 Collar 114 Clamping surface 115 Connection area 116 Central bore 117 Positioning bore 118 Mounting notch 119 Balancing bore 120 Counter flange 121 Second flange mount 122 Outer surface 123 Collar 124 Clamping surface 125 Socket head cap screw 126 Central bore 127 External thread 130 Grinding wheel 131132 Intermediate washer 140 Positioning ring 141 Longitudinal groove 142 Locking pin 144 Clamping surface 145 Intermediate ring 146 Adjusting screw 147 Adjusting pin 148 Spring element 150 Conical connection 151 Internal cone (taper mount) 152 External cone (taper) 153 First face contact surface 154 Second face contact surface 200 Tool holder 210 Z-slide 220 Swivel body 300 Tool head 310 Base 311 Linear guide 312 Ball screw drive 320 First spindle unit 321 First spindle housing 322 First spindle shaft 323 First spindle bearing 324 Drive motor 325 First spindle nose 326 Guide shoe 330 Second spindle unit 321 Second spindle housing 332 Second spindle shaft 333 Second spindle bearing 335 Second spindle nose 336 Guide shoe 350 First balancing unit 360 Second balancing unit 370 Drawbar 372 Clamping nut 400 Rotary turret 500 Workpiece spindle 510 Workpiece 600 Machine bed 700 Machine control 710 Control module 720 Operator panel X, Y, Z Linear axis A Swivel axis B Tool axis C1, C2 Workpiece axis C3 Swivel axis of the turret,

Claims

1. A hub flange (101) for a tool body (130), comprising: a fixed flange (110) defining a tool axis (B), the fixed flange (110) being configured to receive the tool body (130), wherein a first flange socket (111) is formed on the fixed flange (110) for connection to a first spindle shaft (322) which is rotatable about the tool axis (B); and a counterflange (120) which is detachably connected to the fixed flange, wherein the fixed flange (110) and the counter flange (120) are connected to each other via a conical connection (150), the conical connection (150) being arranged coaxially with respect to the tool axis (B) and being formed by an inner cone (151) and an outer cone (152) received in the inner cone (151), characterized in that a first plane contact surface (153) is formed adjacent to the inner cone (151) and a second plane contact surface (154) oriented opposite the first plane contact surface (153) is formed adjacent to the outer cone (152), that the first and second plane contact surfaces (153, 154) extend orthogonally to the tool axis, and that the fixed flange (110) and the counterflange (120) are pressed together at the first and second plane contact surfaces (153, 154) so as to establish a friction fit.

2. The hub flange of claim 1, wherein a second flange socket (121) is formed on the counterflange (120) for connection to a second spindle shaft (332) which is rotatable about the tool axis (B).

3. The hub flange (101) of claim 1 or 2, wherein the inner cone (151) is formed on the fixed flange (110) and the outer cone (152) is formed on the counterflange (120), or wherein the inner cone (151) is formed on the counterflange (120) and the outer cone (152) is formed on the fixed flange (110).

4. The hub flange (101) of any one of the preceding claims, wherein the first plane contact surface (153) is arranged in a region adjacent to the inner cone (151) on the front side, and wherein the second plane contact surface (154) is arranged in a region surrounding the outer cone (152).

5. The hub flange (101) of any of the preceding claims, comprising a plurality of axial screws (125) axially pressing the fixed flange (110) and the counterflange (120) together at the conical connection (150).

6. The hub flange (101) of any of the preceding claims, wherein the hub flange (101) defines first and second clamping surfaces (113, 143) such that the tool body (130) is axially clampable between the first and second clamping surfaces (113, 143).

7. The hub flange (101) of claim 6, comprising a positioning ring (140) which has an axially variable position relative to the counterflange (120), wherein the first clamping surface (113) is configured on the fixed flange (110) and wherein the second clamping surface (143) is configured on the positioning ring (140).

8. The hub flange (101) of claim 7, wherein the counterflange (120) or the fixed flange (110) has an external thread (127) and the positioning ring (140) has an internal thread complementary thereto, in order to change the axial position of the positioning ring (140) by a screwing movement of the positioning ring (140) relative to the counterflange (120), and wherein the hub flange (101) optionally comprises an intermediate ring (142) disposed axially adjacent to the positioning ring (140) for transmitting an axial clamping force from the positioning ring (140) to the tool body (130).

9. The hub flange (101) of claim 7, wherein the positioning ring (140) is axially displaceable on the fixed flange (110) and / or on the counterflange (120), and wherein the hub flange (101) comprises a plurality of threaded elements that are screwed into the counterflange (120) or into the positioning ring (140) in order to change the axial position of the positioning ring (140) relative to the counterflange (120).

10. The hub flange of any one of the preceding claims, wherein the first and / or second flange sockets (111, 121) is formed as an inner or outer cone with a plane contact surface.

11. The hub flange of any one of the preceding claims, comprising an axial through bore (116, 126).

12. A machining tool (100) comprising: a hub flange (101) according to any one of the preceding claims; and a tool body (130), in particular a grinding body, which is clamped on the hub flange (101).

13. A tool head (300) for a machine tool, in particular for a gear cutting machine, comprising: a machining tool (100) according to claim 12, a first spindle unit (320) with a first spindle shaft (322) which is mounted in the first spindle unit (320) so as to be rotatable about the tool axis (B); and a second spindle unit (330) with a second spindle shaft (332) which is mounted in the second spindle unit (330) so as to be rotatable about the tool axis (B), wherein the first spindle unit (320) and the second spindle unit (330) are arranged coaxially with respect to each other in such a way the machining tool (100) is received axially between the first spindle shaft (322) and the second spindle shaft (332).

14. The tool head (300) of claim 13, wherein the machining tool (100) is axially clamped between the first spindle shaft (322) and the second spindle shaft (332) such that an axial compression force acts on both sides of the machining tool (100).

15. The tool head (300) of claim 14, wherein the second spindle shaft (332) and the machining tool (100) each have an axial through bore, wherein the tool head (300) comprises a pull rod (370) extending through the axial through bores of the second spindle shaft (332) and the machining tool (100), the pull rod (370) being connectable at one end to the first spindle shaft (322), and wherein the pull rod (370) is connectable at a second end to the second spindle shaft (332) in such a way that an axial compression force can be generated on the machining tool (100) between the first spindle shaft (322) and the second spindle shaft (332).