Method for gear cutting machine machining with subsequent beveling

Abstract

The invention relates to a method for carrying out gear cutting machine machining, in which, on a gear cutting machine controlled by a control device, cutting teeth are produced or machined on a workpiece clamped on a workpiece spindle arranged at a first machine position by means of a gear cutting tool driven in rotation on a first tool spindle, during the same workpiece clamping operation or during the clamping operation of the machined toothed workpiece on the workpiece spindle arranged at the second machine position, the workpiece is subsequently clamped by the workpiece-specific beveling tool driven by the rotation of the second tool spindle while the workpiece and the workpiece-specific beveling tool are rotated synchronously. In the case of a feed movement between the beveling tool and the workpiece, the beveled surface is produced by cutting the tooth end edges of the tooth flanks of the workpiece cutting teeth with the cutting edges of the beveling tool, the axial distance of the axis of rotation of the workpiece from the beveling tool being not greater than half the pitch of the workpiece cutting teeth during the beveling, and the beveled surface is produced by cutting the tooth flanks of the workpiece cutting teeth with the cutting edges of the beveling tool. The axis intersection angle between the tool axis of rotation and the workpiece axis of rotation and / or the axis intersection angle between the tool axis of rotation and the surface normal to the end face of the workpiece adjacent to the machined tooth end edge differs from 90 DEG by no more than 12 DEG, preferably no more than 8 DEG, in particular no more than 4 DEG, the main directional component of the feed movement travels in the direction of the tool axis of rotation, and the directional component of the cutting edge in the direction of the axis of rotation of the beveling tool is greater than the directional component in a plane of rotation orthogonal thereto when a partial beveling is carried out at least in the region of half the tooth height of the workpiece cutting tooth.

Description

[0001] The present invention relates to a method for machining a gear cutting machine with subsequent chamfering.

[0002] It is a well-known technique to chamfer the tooth edge after the gear cutting has been machined. For example, if the end face of the gear is used as a flat cutting or defining surface in a subsequent operation, its flatness will be disturbed by burrs. In addition, after hardening, the burrs may cause fractures when the gear subsequently rotates in the gear mechanism, and pose a risk of damage to the tooth surface or the components of the gear mechanism. Moreover, such burrs also pose a risk of damage during the handling of the gear cutting or toothed workpiece. If only the burrs are removed without machining the tooth edge itself, there is a risk that the latter becomes glass-hard due to excessive carbonization during hardening and then fractures under stress.

[0003] Many different chamfering methods have been developed to remedy this drawback. In the method disclosed in EP 1 279 127 A1, material in the area of the tooth edge of the workpiece is removed by rolling a chamfering wheel in tooth engagement with the workpiece. After that, the secondary burrs (material accumulations) formed during this so-called rolling deburring or rolling pressure deburring must also be removed. DE 10 2009 018 405 A1 teaches how such secondary burrs can be properly removed.

[0004] As an alternative to this chamfering by plastical forming, a chamfer can be formed on the tooth edge by cutting. According to DE 10 2009 019 433 A1, a machining tool that is substantially cylindrical and has at least one cutting edge is clamped on a tool spindle.

[0005] DE 10 2013 012 797 A1 discloses a method that also works in a cutting manner, in which the chamfering wheel is substantially similar to a scraping wheel, and an additional inclination angle is set based on the standard configuration of scraping engagement. The axis distance set here corresponds in magnitude to the sum of the workpiece radius and the tool radius, and the chamfering can be performed using a feed movement that is mainly parallel to the workpiece axis, or the chamfering can be incorporated into the chamfering tool through a specific design of the chamfering tool. The chamfering process described in the non-patent literature ″Advances in Manufacturing Engineering and Materials″ on pages 18 to 26 also acts in cooperation with a feed movement parallel to the workpiece axis, in which a workpiece-specific chamfering tool simultaneously machines the two tooth edge ends of the tooth gap, and the component of the cutting speed parallel to the workpiece axis is directed towards the axial tooth cutting center on one edge and away from the axial tooth cutting center on the other edge.

[0006] DE 10 2013 015 240 A1 discloses another chamfering process using a workpiece-specific chamfering cutter (so-called "bevel cutting milling"), the contour of which is designed such that when the chamfering milling teeth pass through the tooth gaps in the workpiece teeth, the workpiece teeth are fully chamfered on both tooth surfaces of the tooth gap. These "chamfer-cut millers" look similar to hobs, but the flight circles in the same contour area overlap. DE 10 2018 001 477 describes another chamfering operation that is closer to hobbing.

[0007] According to the principle of the "chamfer-cut miller" disclosed in DE 10 2013 015 250 A1, the tooth edges are also removed by fly-cutting to produce, for example, bevels on the teeth of a gear mechanism. Here, a rotating fly-cutter, implemented in the form of an end mill for example, is aligned with its tool rotation axis at an angle to the axis of the workpiece teeth such that the tooth surfaces of the workpiece teeth are machined in one pass in the machining area by a cutting process parallel to the final geometry to be generated. Such processes are described, for example, in the non-patent literature "Innovative Zahnradfertigung" by T. Bausch, Expert-Verlag, 3rd edition, page 323.

[0008] The method disclosed in DE 10 2014 218 082 A1 is similar to the gear shaving chamfering of DE 10 2013 012 797 A1, but the inclined axis structure has been incorporated into the tooth-cutting machine structurally.

[0009] According to DE 10 2018 108 632 A1, yet another chamfering technique has been learned, in which a pin-type milling cutter is moved along the tooth edge by moving the machine axis. This chamfering technique is particularly suitable for the front edges that are difficult to reach easily with a "chamfer-cut miller" or a hob-type cutter due to interfering contours on the workpiece.

[0010] WO 2019 / 017248 A1 proposes using a pressing process such as roll deburring, but moves the weight of secondary burr generation away from the tooth surface in the direction of the end face.

[0011] In terms of the arrangement structure, according to EP 1 495 824 A2, it has been learned that the machining tool for chamfering the tooth edges is placed on the same axis as the hob for producing the workpiece teeth.

[0012] All these chamfering techniques have their advantages and disadvantages. Based on the object of providing a gear cutting machine machining with subsequent chamfering, the present invention specifically realizes a satisfactory combination of the applicability of machining workpieces with interfering profiles and the simplicity of process design.

[0013] This object is achieved in terms of process engineering by a method for gear cutting machine machining, wherein on a gear cutting machine controlled by a control device, gear teeth are generated or machined on a workpiece clamped on a workpiece spindle arranged at a first machine position by a gear cutting tool rotationally driven on a first tool spindle, and subsequently, in the same workpiece clamping operation or in a clamping operation on the machined toothed workpiece clamped on a workpiece spindle arranged at a second machine position, with the workpiece and a workpiece-specific chamfering tool rotationally driven by a second tool spindle rotating synchronously, and with a feed movement between the chamfering tool and the workpiece, a chamfer is generated by cutting the tooth tip edge of the tooth flank of the workpiece teeth with the cutting edge of the chamfering tool, wherein during chamfering, the axial distance between the rotational axis of the workpiece and the chamfering tool is not greater than half of the pitch of the workpiece gear teeth, the axis crossing angle between the tool rotational axis and the workpiece rotational axis and / or the axis crossing angle between the tool rotational axis and the surface of the end face normal to the workpiece and adjacent to the machined tooth tip edge differ from 90° by no more than 12°, preferably no more than 8°, especially no more than 4°, the main directional component of the feed movement travels in the direction of the tool rotational axis, and specifically, at least in the region of at least half of the tooth height of the workpiece gear teeth during partial chamfering, the directional component of the cutting edge in the direction of the rotational axis of the chamfering tool is greater than the directional component in the rotational plane orthogonal thereto.

[0014] This combination of axis crossing angle adjustment, feed movement, cutting position configuration, and axial distance limitation ensures that the chamfer can be machined by a continuous process even near an interfering profile, thus also saving time, which is different from the case mainly of axial feed movement or pin milling cutter chamfering where the chamfering tool moves along the tooth edge during form milling.

[0015] In a preferred method design, it is proposed to chamfer the tooth tip edges other than those of the same tooth gap chamfered by the chamfering tool using an additional chamfering tool rotationally driven by a third tool spindle.

[0016] Due to the additional chamfering tool, the advantage of this variant is that the machining of the two tooth tip edges of the tooth gap is avoided from generating a connection, and thus, by workpiece rotation, it is possible to avoid machining deviations caused by the time difference (even very small) based on the successive machining of these two tooth edges.

[0017] In this regard, it is also preferably proposed that when chamfering is carried out using a chamfering tool and / or an additional chamfering tool, preferably when chamfering is carried out using both tools, the component of the cutting speed oriented parallel to the workpiece axis is directed away from the axial center of the workpiece teeth (i.e., away from the tooth flank) (in the direction of the machined front side). This reduces the risk of forming secondary burrs on the tooth flank.

[0018] In another preferred embodiment, it is proposed to control the chamfering using the same control device as that used for the gear cutting machining carried out by the gear cutting machine tool. Regardless of the problem of the feed movement, this design is also regarded as worthy of protection. The present invention thus also relates to a method for carrying out gear cutting machining, wherein, on a gear cutting machine controlled by a control device, gear teeth are produced or machined on a workpiece clamped on a workpiece spindle arranged at a first machine position by a gear cutting tool rotationally driven on a first tool spindle, and subsequently, in the same workpiece clamping operation or in a clamping operation on the machined toothed workpiece clamped on a workpiece spindle arranged at a second machine position, with the workpiece and a workpiece-specific chamfering tool rotationally driven by a second tool spindle synchronized in rotation, and with a feed movement carried out between the chamfering tool and the workpiece, a chamfer is produced by cutting the tooth end edge of the tooth flank of the workpiece teeth with the cutting edge of the chamfering tool, wherein, during the chamfering, the axial distance between the rotation axis of the workpiece and the chamfering tool is not greater than half of the pitch of the workpiece teeth, the axis crossing angle between the tool rotation axis and the workpiece rotation axis and / or the axis crossing angle between the tool rotation axis and the surface of the end face normal to the workpiece and adjacent to the machined tooth end edge deviates from 90° by no more than 12°, preferably no more than 8°, particularly no more than 4°, specifically, at least when carrying out partial chamfering in the region of the tooth head of the workpiece teeth, the component of the cutting edge oriented in the direction of the rotation axis of the chamfering tool is greater than the component in the rotation plane orthogonal thereto, and wherein the chamfering is controlled using the same control device as that used for the gear cutting machining carried out by the gear cutting machine tool.

[0019] Therefore, the control device is not a separate control device that only targets chamfering and receives external inputs, but already internally has the control parameters of the previous gear cutting production or machining, including any setting changes made within the batch. This improves the safety and reliability of the chamfering method.

[0020] In this regard, it is preferably proposed to incorporate at least one control parameter of the chamfering into the chamfering as the control parameters of the gear cutting machining carried out by the gear cutting machine tool change. This improves the flexibility of the method.

[0021] In another preferred embodiment, it is proposed to influence the course of the transition line between the flank and the chamfer during chamfering by taking into account the amount of material to be removed during subsequent hard finishing operations compared to the final geometry of the workpiece tooth cutting.

[0022] By taking into account in advance how the course of the transition line changes due to hard finishing, this improves the final accuracy of the chamfer after subsequent hardening and hard finishing. The setting carried out is preferably such that the transition line is parallel to the leading edge surface in the final geometry after hard finishing. The workpiece-specific profile machining of the chamfering tool can be determined, for example, by inverse transformation of a given transition line (after chamfering) using a given axial kinematics.

[0023] In another preferred embodiment, it is proposed to carry out chamfering in the presence of a cooling fluid and / or lubricating fluid originating from the gear cutting machine machining carried out by a gear cutting machine tool. This is preferably a semi-dry machining process, since although no additional lubricant / fluid is used during chamfering, the cooling fluid and / or lubricating fluid from the previous gear cutting machine machining still wets the workpiece.

[0024] In another preferred embodiment, an additional burr removal device is used, specifically a brush to remove burrs formed due to chamfering. Such secondary burrs can specifically occur in the case of helical-tooth workpieces with a large helix angle; by combining the aforementioned preferred uniform cutting direction component parallel to the workpiece axis during chamfering, a burr-free chamfered workpiece can be provided specifically only by using a brush acting in the region of the end face.

[0025] In another preferred embodiment, it is proposed that the control device controls the chamfering so that the course of the transition line between the chamfer and the flank deviates from being parallel to the end face. As explained above, different courses are preferably controlled in such a way that parallelism is restored after hard finishing. This aspect of the invention is also considered advantageous and worthy of protection regardless of the course of the feed movement.

[0026] The invention thus also relates to a method for machining with a hobbing machine, wherein, on a hobbing machine controlled by a control device, a hobbing cutter rotationally driven on a first tool spindle produces or machines hobbing teeth on a workpiece clamped on a workpiece spindle arranged at a first machine position, and subsequently, in the same workpiece clamping operation or in a clamping operation on the machined toothed workpiece clamped on a workpiece spindle arranged at a second machine position, with the workpiece and a workpiece-specific chamfering cutter rotationally driven by a second tool spindle rotating synchronously, and with a feed movement being carried out between the chamfering cutter and the workpiece, a chamfer is produced by cutting the tooth tip edge of the tooth surface of the workpiece teeth with the cutting edge of the chamfering cutter, wherein, during chamfering, the axial distance between the rotational axis of the workpiece and the chamfering cutter is not greater than half of the pitch of the workpiece hobbing teeth, and the axis crossing angle between the tool rotational axis and the workpiece rotational axis and / or the axis crossing angle between the tool rotational axis and the surface of the end face normal to the workpiece and adjacent to the machined tooth tip edge deviate from 90° by no more than 12°, preferably no more than 8°, particularly no more than 4°, specifically, at least when carrying out partial chamfering in the region of the tooth head of the workpiece hobbing teeth, the directional component of the cutting edge in the direction of the rotational axis of the chamfering cutter is greater than the directional component in the rotational plane orthogonal thereto, and wherein the control device controls the chamfering so that the path of the transition line between the chamfer and the tooth surface deviates from being parallel to the end face.

[0027] In a possible embodiment, it is proposed that the axis crossing angle is adjustable, specifically via the rotational axis, specifically under NC control.

[0028] In another preferred embodiment, it is proposed that the second tool spindle and the third tool spindle are carried by a common carrier, and the common carrier specifically has at least two freely movable angles.

[0029] The above chamfering is applicable to external hobbing teeth. However, it is also contemplated for chamfering internal hobbing teeth. To achieve this, a spindle head with a bevel gear mechanism is preferably provided for the chamfering cutter.

[0030] Regardless of the question of how the feed movement will be or can be carried out, this method variant for internal gear cutting machining is also regarded as advantageous and as being worthy of protection in itself. The invention thus also relates to a method for carrying out gear cutting machining, in which, on a gear cutting machine controlled by a control device, internal teeth are generated or machined on a workpiece clamped on a workpiece spindle arranged at a first machine position by a gear cutting tool rotationally driven on a first tool spindle, and subsequently, in the same workpiece clamping operation or in a clamping operation on a machined internally toothed workpiece arranged on a workpiece spindle at a second machine position, with the workpiece and a workpiece-specific chamfering tool rotationally driven by a second tool spindle rotating synchronously, and with a feed movement being carried out between the chamfering tool and the workpiece, a chamfer is generated by cutting the tooth tip edge of the tooth surface of the internal teeth of the workpiece with the cutting edge of the chamfering tool, wherein, during chamfering, the axial distance between the rotational axis of the workpiece and the chamfering tool is not greater than half of the pitch of the workpiece teeth, and the axis crossing angle between the tool rotational axis and the workpiece rotational axis and / or the axis crossing angle between the tool rotational axis and the surface of the end face normal to the workpiece and adjacent to the machined tooth tip edge deviates from 90° by no more than 12°, preferably no more than 8°, particularly no more than 4°, specifically, the directional component of the cutting edge in the direction of the rotational axis of the chamfering tool is greater than the directional component in the rotational plane orthogonal thereto.

[0031] The internal gear cutting machining variant thus defined can be combined with the various aspects of the chamfering described above.

[0032] In a preferred design in this regard, for the equipment, two free movement angles for carrying out chamfering are provided, specifically two linear free movement angles, one of which has a main directional component parallel to the workpiece rotational axis and the other of which has a main directional component radial to the workpiece rotational axis. Preferably, these are achieved by a cross-slide arrangement structure.

[0033] The method can be carried out on a horizontal machine (horizontal workpiece rotation axis). In this case, preferably, the linear axis for moving the main machining tool on the one hand and for positioning the chamfering tool on the other hand is arranged on the opposite side of the workpiece rotation axis. Furthermore, the tip of the chamfering tool preferably points towards the side of the linear movement axis on the chamfered side, which axis preferably extends parallel to the workpiece rotation axis. In another preferred embodiment, the internally toothed workpiece is clamped onto a workpiece mandrel, wherein the clamping is such that there is an axial distance between the axially end side of the internally toothed workpiece close to the clamping and the mandrel end region, which mandrel end region is located in a projection orthogonal to the workpiece rotation axis within the internally toothed workpiece and axially points in the direction of the axially end side of the internally toothed workpiece remote from the clamping. In this way, the chamfering head carrying the chamfering tool can be axially moved deeply into the internally toothed workpiece in order to chamfer the axially end side of the internally toothed workpiece closest to the clamping even without changing the clamping.

[0034] A direct drive can be used as the rotational drive for the chamfering tool. However, preferably, an indirect drive and a drive force device are realized by a gear mechanism, specifically by a bevel gear mechanism; a simple belt drive can also be envisaged.

[0035] When implemented using a vertical machine (vertical workpiece rotation axis), a variant is considered in which the machining head for carrying out the main machining carries on its back the machining head for carrying out the chamfering process. In this variant, the chamfering head receives all the movement axes available to the main machining head, and these movement axes can be used as positioning axes, cross-feed axes, and feed axes. In another preferred variant, the chamfering tool is additionally arranged to be displaceable relative to the main machining head orthogonally to its rotation axis. The displacement axis can be realized as an NC axis or as a simple adjustment axis, for example in order to move the machining tool between a retracted position and a working position, for example where the main orientation component is parallel to the rotation axis of the main machining tool. However, a defined angular setting of such a travel axis relative to the rotation axis of the machining tool for the main machining is also considered, such that chamfering machining is carried out in a configuration where the rotation axis of the machining tool for the main machining and the workpiece axis are at an axis crossing angle, which axis crossing angle is selected to be large enough such that there is no collision between the main machining tool and the workpiece while carrying out the chamfering machining. This variant can also be envisaged in combination with the variant in which the chamfering tool is movable relative to the main machining head.

[0036] In other designs, the chamfering head can also be arranged independently of the main machining head in a vertical machine and can be positioned.

[0037] For a device, this object is achieved by an arrangement structure for performing gear hobbing machine machining. By means of this arrangement structure, on a gear hobbing machine controlled by a control device, gear teeth are generated or machined on a workpiece clamped on a workpiece spindle arranged at a first machine position by a gear hobbing tool rotationally driven on a first tool spindle. Subsequently, in the same workpiece clamping operation or in a clamping operation on the machined toothed workpiece clamped on a workpiece spindle arranged at a second machine position, with the workpiece and a workpiece-specific chamfering tool rotationally driven by a second tool spindle rotating synchronously, and with a feed movement being carried out between the chamfering tool and the workpiece, a chamfer is generated by cutting the tooth end edge of the tooth flank of the workpiece teeth with the cutting edge of the chamfering tool, wherein during chamfering, the axial distance between the rotational axis of the workpiece and the chamfering tool is not greater than half of the pitch of the workpiece gear teeth, the axis crossing angle between the tool rotational axis and the workpiece rotational axis and / or the axis crossing angle between the tool rotational axis and the surface of the end face normal to the workpiece adjacent to the machined tooth end edge differ from 90° by no more than 12°, preferably no more than 8°, and in particular no more than 4°, the main directional component of the feed movement travels in the direction of the tool rotational axis, and specifically, when performing partial chamfering at least in the region of half of the tooth height of the workpiece gear teeth, the directional component of the cutting edge in the direction of the rotational axis of the chamfering tool is greater than the directional component in the rotational plane orthogonal thereto.

[0038] As already described above for the method according to the invention, the arrangement structure can be designed such that an additional chamfering tool rotationally driven by a third tool spindle chamfers an end edge different from the tooth end edge of the same tooth gap chamfered by the chamfering tool. This variant can also be achieved regardless of whether one directional component of the feed movement is dominant or which directional component is dominant.

[0039] It can also be proposed that the control device for performing chamfering is the same as the control device that also controls the gear hobbing machine machining performed by the gear hobbing machine tool. This variant can also be achieved regardless of whether one directional component of the feed movement is dominant or which directional component is dominant.

[0040] In an equally preferred embodiment, it is proposed to design / program the control device to control the chamfering such that the path of the transition line between the chamfer and the tooth flank deviates from being parallel to the end face. This variant can also be achieved regardless of whether one directional component of the feed movement is dominant or which directional component is dominant.

[0041] The gear hobbing machine for performing this method preferably also performs the main gear hobbing machine machining operation on the gear hobbing machine itself; as described in more detail elsewhere, it is preferably transferred to the chamfering area of the gear hobbing machine via a loading system such as a gantry loader. The advantages of the gear hobbing machine according to the invention result from the above advantages of the method according to the invention.

[0042] The number of cutting edges on the chamfering tool is preferably not more than four, specifically only two or only one. The working diameter of the chamfering tool relative to the pitch circle is preferably between one pitch and four pitches of the teeth to be chamfered.

[0043] Additional features, details, and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings, in which:

[0044] Figure 1 Schematically shows a gear cutting machine,

[0045] Figure 2 Schematically shown in a plan view Figure 1 of the chamfering area of the gear cutting machine,

[0046] Figures 3A and 3B illustrate the feed movement,

[0047] Figure 4 Shows a perspective view of the chamfering machine operation,

[0048] Figure 5 Shows a pure schematic diagram of internal gear chamfering,

[0049] Figure 6 Shows a part of a shaving machine with a chamfering unit,

[0050] Figure 7 Shows Figure 6 the chamfering unit in the machining mode, and

[0051] Figure 8a 、 Figure 8b 、 Figure 8c Shows another gear shaving machine with a chamfering unit as a whole and in parts in different positions.

[0052] In the embodiment now being referred to Figure 1 and explained, a gear cutting machine 500 in the form of a horizontal machine is provided schematically. In Figure 1 , the workpiece spindle rotation axis C is schematically shown on the main machining station 50 side, while the workpiece spindle rotation axis C2 is schematically shown on the chamfering station 100 side. Both stations 50, 100 belong to the gear cutting machine 500, which is represented in Figure 1 by a common frame 200 and a reloading system 80. The common frame can also be designed as a common machine tool, and the reloading system is only schematically shown in Figure 1within and is able to pick up a workpiece from a main workpiece mandrel defining a (main) workpiece mandrel axis C and transfer it to a workpiece mandrel 10 associated with a (beveling) workpiece mandrel axis C2. Thus, the transfer takes place within the gear cutting machine 500, and the two workpiece mandrel axes C and C2 are parallel and horizontally extended, preferably coaxially extended. A partition wall 75 may be provided between the main machining station 50 and the beveling station 100. A tool head (not shown) having corresponding movement options for performing gear cutting machine machining is also provided on the main machining station 50. In this case, the main machining station 50 is designed for gear shaving, but the present invention is not limited thereto; for example, hobbing or gear forming may also be performed.

[0053] In Figure 2 it, in a possible embodiment, a beveling station or a beveling area 100 of the gear cutting machine 500 is shown. On the workpiece side, the workpiece mandrel 10 is shown as having a workpiece mandrel axis C2, which extends in the Z direction (here horizontally). Preferably, when machining a shaft-shaped workpiece, a tailstock 11 may be used opposite to the workpiece mandrel 10.

[0054] The linear guiding device for the tool carriage 7 extends parallel to the Z axis, and this linear guiding device is represented by two guide rails 8. Two tool heads 21, 22 are arranged on the carriage 7, and these two tool heads can be axially moved along a (radial) axis X relative to the linear carriage 7 through another linear guiding device, and this axis X has linear travel axes X1 and X2. The linear guiding device is represented by guide rails 81, 82. The beveling tool rotation axes are represented as B1 and B2 in Figure 2 it, and the beveling tools are represented as 1 and 2. In this embodiment, one or more linear axes X (X1, X2) are also horizontally arranged; thus, Figure 2 the representation in

[0055] Figure 2 corresponds to a view from above. A centering sensor 3 is provided between the beveling tools 1 and 2 (here there is a pneumatic actuator (not shown)). Through the centering sensor 3, the position of the tooth gap of the gear teeth to be beveled can be determined in a manner well known to those skilled in the art.

[0056] In this implementation, according to a preferred embodiment, the workpiece mandrel axis C2 is a horizontal axis, as already explained, but in principle a vertical machine may also be provided. In this case, the linear mobility X can still be used as the radial movement of the gear teeth clamped on the workpiece mandrel 10.

[0057] In the variant Figure 2 illustrated, the first chamfering tool 1 is used to chamfer the tooth end edge (specifically also in the tooth root region) of one tooth flank (for example, the left tooth flank), and the other chamfering tool 2 is used to chamfer the other tooth flank (for example, the right tooth flank). Here, preferably, the rotation directions of the spindle axes B1 and B2 are controlled in opposite directions by means of a controller represented by reference numeral 99 in Figure 2 . Additionally, the rotation direction is adjusted such that the tooth edge to be chamfered is cut from the inside, away from the axial tooth center, towards the outside, in order to avoid burr formation on the tooth flank side.

[0058] All spindle arrangements known to those skilled in the art can be used as drive spindles, such as high-frequency spindles; the interface between the chamfering tool and the spindle can be designed as an HSK interface. The double-guide linear guide is also shown only by way of example; specifically, only one dovetail guide, for example, can be provided, and a wear protection device of appropriate shape slides on this guide. Figure 1 The internal reloading system 80 in the gear cutting machine shown in

[0059] transfers the workpiece that has been machined on the main station (main machining area) 50 using a gear cutting machine to the workpiece spindle 10 in the chamfering area 100 of the gear cutting machine 500 without changing the axis orientation of the workpiece during the transfer.

[0060] In the working mode shown in FIG. 3B, the controller 99 is designed to perform the feed movement by superimposing a radial movement X and an axial movement Z, where the radial movement component is dominant.

[0061] In both cases, by adjusting the feed movement, the chamfering can even be close to the interfering contour, represented by an asterisk in FIG. 3. If necessary, a pure axial feed movement can also be considered, especially when the interfering contour is not taken into account, or even a superimposed feed movement with a predominant axial component. At least one of these feed movement concepts is stored in the controller 99 and is available for use.

[0062] In Figure 4Also shown in perspective is the machining operation of the chamfering tool 1. In this embodiment, the workpiece rotation axis C2 and the tool rotation axis B1 have a 90° axis intersection angle since they are parallel to the axes Z and X which are perpendicular to each other. Furthermore, in the embodiment shown, the axial distance of the rotation axes is 0, i.e., the extension line of the rotation axis B1 intersects the extension line of the rotation axis C2. In other embodiments, the axial distance can also be made smaller and / or the deviation of the axis intersection angle from 90° can be made smaller. In the variant shown, the rake face 6 of the cutting tooth 4 extends orthogonally to the workpiece rotation axis C2. In the case of an inclined end face, it can also be proposed to make the tool rotation axis orthogonal to the surface normal of the inclined end face instead of making this tool rotation axis orthogonal to the Z axis. To adjust the axis intersection angle, the tool head (20, 21, 22) can have an additional rotation axis (not shown in Figure 2 the figure).

[0063] The workpiece rotation axis C2 and the tool rotation axis B1 are synchronously controlled by the controller 99 such that the cutting edge 15 of the chamfering tool 1 engages in a cutting machining operation with the tooth edge 5 of the workpiece cutting tooth 4 and a chamfer is produced there. The position of the cutting edge 15 is realized in a workpiece-specific manner such that in the final machining position where the feed movement is completed on the cutting tooth, the predetermined chamfer shape of the now-formed chamfer is achieved, replacing the tooth end edge 5.

[0064] In this case, the transition line between the tooth face and the chamfer may preferably not yet be formed, for example, parallel to the end face 6 as desired, but deviate from this end face such that such a parallel transition line is only formed after subsequent hard finishing to the final dimensions of the workpiece cutting tooth 5.

[0065] For the variant Figure 2 explained for reference, the chamfering tools 1 and 2 are formed such that only one tooth edge 5 is chamfered and not the opposite tooth edge of the tooth gap. However, in another embodiment, the chamfering tool (with the tool rotation axis B) can also machine both tooth edges. Then, the "double chamfering tool configuration" shown Figure 2 will no longer be required, and only one chamfering tool head (20) with the tool rotation axis (B) will be needed.

[0066] If chamfering still produces secondary burrs, for example, on the front side 6, these secondary burrs can be removed by a deburring unit such as a brush or a brush device not shown in the figure.

[0067] The controller 99 controls the entire gear cutting machine 500, i.e., the main machining area 50 and the bevel cutting area 100. Thus, changes in the machine axis settings during main machining 50 can be checked within the control system to determine whether a correction of the bevel cutting is required, and if necessary, the correction settings for the bevel cutting method can be made and automated within the control system. However, in principle, it can also be proposed to perform the above bevel cutting on a separate bevel cutting station.

[0068] The above bevel cutting technique has been described by way of example for external gear cutting, but the above bevel cutting technique is also suitable for bevel cutting of internally toothed workpieces ( Figure 5 ). For this purpose, the tool head / bevel cutting tool penetrates, for example, through a corresponding projection of the mandrel head into the space defined by the profile of the internal teeth, as seen by the projection on the workpiece rotation axis, and the mandrel head is preferably designed with a bevel gear mechanism. As Figure 2 shown, the movement axes can be retained, as Figure 2 shown for the double movement axes, or only a single movement axis can be retained for the bevel cutting tool.

[0069] The following describes the specific design of the gear cutting machine with reference to Figure 6 to FIG. 8, which produces / machines internal teeth and is equipped with a bevel cutting unit operating according to one or more of the above aspects.

[0070] As can be seen from Figure 6 showing the relevant details of the gear shaving machine 600, the gear shaving machine 600 is designed as a so-called horizontal machine having a horizontally arranged workpiece spindle rotation axis C6. On the workpiece side, the workpiece 602 in the form of internal teeth is clamped to the workpiece spindle 610.

[0071] On the tool side, there is a shaving wheel 601 having a tool rotation axis B6 as the main machining tool, which is arranged on the tool head 604 in a common manner and manufactures or machines the internally toothed workpiece 602 through the gear shaving process. The tool head 604 can linearly move along the linear axis Y6, and the carriage arrangement structure provided for realizing this linear movement Y6 is pivotally arranged with a pivot axis A6. A support structure enabling pivoting about the axis A6 is provided in the form of a transverse carriage, through which two additional linear travel axes X6 and Z6 are realized. In the design described by way of example, the Z6 axis extends parallel to the workpiece spindle axis C6, and the X6 axis is a radial cross-feed axis and is parallel to the pivot axis A6.

[0072] In Figure 6In the foreground, a chamfering unit 640, which is also implemented as a transverse carriage arrangement structure, is shown. A first carriage 641 can move along a guide device provided on the machine support side along a linear movement axis Z4 that extends parallel to the workpiece rotation axis C6. The first carriage 641 forms a guide arrangement structure for a carrier 642 carried by the guide arrangement structure, and the carrier can move along another radial axis X4 relative to the first carriage 641, where the axis X4 is orthogonal to the axis Z4. A chamfering head 643 held by the second carriage 642 can be positioned relative to the internal toothed workpiece 602 via these two axes X4 and Z4.

[0073] In Figure 6 the position shown, a chamfering tool 644 mounted on the chamfering tool head 643 so as to be drivable to rotate about its axis is in an inactive state, and skiving machining is performed by a skiving wheel 601. Depending on the dimensions of the tool-side machining tools (601, 641), skiving and chamfering machining can also be performed simultaneously, depending on the dimensions of the workpiece; for the size specifically shown here, sequential machining is provided. The chamfering operation is shown in Figure 7 wherein smaller details of the gear cutting machine 600 are shown enlarged from different angles. In Figure 7 the illustration, the chamfering tool 644 chamfers the tooth edge of the internal toothed workpiece 602 on the axial end side facing the tool side. In the case where the relative positioning between the chamfering tool 641 and the workpiece 602 changes, the tooth edge is machined on the axial end side away from the tool. For this purpose, first, the chamfering tool 641 is disengaged using the X4 axis; then, it is axially moved along the Z4 axis to the level of the other axial end side, and then, it is fed backward using the X4 axis to perform chamfering there. In addition to positioning, the X4 axis and / or the Z4 axis can also be used as feed axes during chamfering.

[0074] Figure 8a Another exemplary embodiment in the form of another gear cutting machine 800 is shown, which is also constructed as a skiving machine with a skiving wheel S. The gear cutting machine 800 is designed as an upright machine with a vertical workpiece rotation axis denoted here as C8, where the internal toothed workpiece itself is not shown, but only the workpiece table is shown.

[0075] On the tool side, the tool rotation axis is designated by B8, and the tool head by 78. The latter can in turn pivot about the pivot axis A8 and can be tangentially displaced by means of a pivot carriage 76 (axis Y8). The pivot unit which enables pivoting about axis A8 can also be displaced vertically along the linear axis Z8 and can also be displaced linearly along the radial axis X8 towards or away from the workpiece table. The scraping wheel S thus has three linear axes and one rotational NC axis for its positioning relative to the workpiece clamped on the workpiece table for positioning, cross-feed and advancement during scraping.

[0076] In the present exemplary embodiment, the tool head 78 carries the chamfering unit 88 piggyback fashion. This means that the chamfering head 843 can be displaced on all the movement axes X8, Z8, A8, Y8, as can the scraping head 78 as well. Similar to Figure 7 the construction shown, the chamfering head 843 carrying the chamfering tool 844 can likewise be displaced axially relative to the tool head 78 via the movement axis Z84. This axis can be an NC axis which is also used for chamfering machining or can be a pure positioning axis via which the chamfering head 843 can be displaced from a first retracted position ( Figure 8b ) to a second extended position ( Figure 8c ), in which first retracted position the internal gear machining is not cut by the scraping wheel S and in which second extended position its chamfering machining is not cut by the scraping wheel S into a tool-side interference profile. In this construction, the main machining carried out with the scraping wheel S takes place at an axis crossing angle relative to the workpiece rotation axis, and the chamfering does not take place at the same axis crossing angle but rather takes place along axes Z84 and C8 parallel to the axis or at an axis crossing angle smaller than the axis crossing angle of the scraping.

[0077] In the present exemplary embodiment, the chamfering unit 80 is arranged on the workpiece-facing side of the main machining head 78, but a lateral arrangement configuration is also conceivable. The orientation of the rotation axis of the chamfering tool 844 can thus preferably be a radial orientation, i.e., can extend parallel to the X8 axis, but can also be a tangential orientation, i.e., parallel to the Y8 axis (while still engaging laterally, i.e., radially positioned relative to the engagement area). For machining external teeth using a hobbing machine 800, the tip of the chamfering tool 844 will point in the direction of the workpiece rotating table and will thus be arranged contrary to the Figure 8c example. For this purpose, the chamfering tool head 843 will be pivoted 180° relative to its mounting in the chamfering unit 80 or will be disassembled and reinstalled in a 180°-changed orientation. An axis crossing angle formed by a constructive relative arrangement configuration between the axes B8 and Z84 is also conceivable such that when Z8 and Z84 are arranged parallel, the scraping wheel S can pivot about this axis crossing angle without the risk of collision.

[0078] In Figure 6 In all variants of FIGS. 6 to 8, the chamfering tool can be driven by a small-sized direct drive, but preferably by an indirect drive which is connected via a gear mechanism or a belt drive to the rotating shaft of the unit, which is coaxial with the workpiece rotation axis.

[0079] The invention is not limited to the details and embodiments described in the above description of the drawings. On the contrary, the individual or combined features of the above description and the following claims are important for implementing the various embodiments of the invention.

Claims

1. A method for machining with a gear cutting machine, wherein, on a gear cutting machine (500) controlled by a control device, gear teeth are generated or machined on a workpiece clamped on a workpiece spindle arranged at a first machine position by a gear cutting tool rotationally driven on a first tool spindle. Subsequently, in the same workpiece clamping operation or in a clamping operation on a machined toothed workpiece on a workpiece spindle (10) arranged at a second machine position, with the workpiece and a workpiece-specific chamfering tool (1) for the workpiece rotationally driven by a second tool spindle rotating synchronously, and with a feed movement (V) being carried out between the chamfering tool and the workpiece, a chamfer is generated by cutting the tooth end edge (5) of the tooth flank of the gear teeth of the workpiece with the cutting edge (15) of the chamfering tool, wherein during chamfering, the axial distance between the rotational axis of the workpiece and the chamfering tool is not greater than half of the pitch of the gear teeth of the workpiece, the axis crossing angle between the tool rotational axis and the workpiece rotational axis and / or the axis crossing angle between the tool rotational axis and the surface of the end face (6) normal to the workpiece and adjacent to the machined tooth end edge deviates from 90° by no more than 12°, preferably no more than 8°, and in particular no more than 4°. The main directional component of the feed movement (V) travels in the direction of the tool rotational axis, and at least when performing partial chamfering in the region at least half of the tooth height of the gear teeth of the workpiece, the directional component of the cutting edge in the direction of the rotational axis of the chamfering tool is greater than the directional component in the rotational plane orthogonal thereto.

2. The method according to claim 1, wherein, an additional chamfering tool rotationally driven by a third tool spindle is used to chamfer a tooth end edge different from the tooth end edge of the same tooth gap chamfered with the chamfering tool.

3. The method according to claim 1 or 2, wherein, when chamfering with the chamfering tool and / or the additional chamfering tool, preferably when chamfering with both tools, the directional component of the cutting speed parallel to the workpiece axis is directed away from the axial center of the gear teeth of the workpiece.

4. The method according to one of the preceding claims, wherein, the chamfering is controlled by the same control device as the gear cutting machine machining carried out with the gear cutting machine machining tool.

5. The method according to claim 4, wherein, at least one control parameter of the chamfering is incorporated into the chamfering as the control parameters of the gear cutting machine machining carried out with the gear cutting machine machining tool change.

6. The method according to claim 5, wherein, taking into account the allowance to be removed in a subsequent hard finishing operation compared to the final geometric structure of the gear teeth of the workpiece, the control parameters affect the path of the transition line between the tooth flank and the chamfer during chamfering.

7. The method according to one of the preceding claims, wherein, the chamfering is carried out in the continuous presence of a cooling fluid and / or a lubricating fluid sourced from the gear cutting machine machining carried out with the gear cutting machine machining tool.

8. The method according to one of the preceding claims, wherein, an additional burr removal device is utilized, specifically a brush is utilized to remove burrs formed by chamfering.

9. The method according to one of the preceding claims, wherein, the control device controls the chamfering such that the path of the transition line between the chamfered surface and the tooth surface deviates from being parallel to the end face.

10. The method according to one of the preceding claims, wherein, the axis crossing angle is variably adjustable, specifically via the rotational axis, specifically under NC control.

11. The method according to one of claims 2 to 10, wherein, the second tool spindle and the third tool spindle are carried by a common carrier, and the common carrier specifically has at least two freely movable angles.

12. The method according to one of the preceding claims, wherein, the machined and chamfered gear teeth are internal gear teeth.

13. An arrangement structure for gear cutting machine machining, by means of which, on a gear cutting machine controlled by a control device, gear teeth are generated or machined on a workpiece clamped on a workpiece spindle arranged at a first machine position by a gear cutting tool rotationally driven on a first tool spindle, and subsequently, in the same workpiece clamping operation or in a clamping operation on the machined toothed workpiece on a workpiece spindle arranged at a second machine position, with the workpiece and a workpiece-specific chamfering tool rotationally driven by a second tool spindle rotating synchronously, and with a feed movement being carried out between the chamfering tool and the workpiece, a chamfered surface is generated by cutting the tooth end edge of the tooth surface of the workpiece teeth with the cutting edge of the chamfering tool, wherein, during chamfering, the axial distance between the rotational axis of the workpiece and the chamfering tool is not greater than half of the pitch of the workpiece gear teeth, the axis crossing angle between the tool rotational axis and the workpiece rotational axis and / or the axis crossing angle between the tool rotational axis and the surface of the end face adjacent to the machined tooth end edge normal to the workpiece deviates from 90° by no more than 12°, preferably no more than 8°, and particularly no more than 4°, the main directional component of the feed movement travels in the direction of the tool rotational axis, and specifically, at least in the region at least half of the tooth height of the workpiece gear teeth during partial chamfering, the directional component of the cutting edge in the direction of the rotational axis of the chamfering tool is greater than the directional component in the rotational plane orthogonal thereto.

14. The arrangement structure according to claim 13, the arrangement structure being provided with a control device which is designed and programmed to control the method according to one of claims 1 to 12.

15. A gear cutting machine, the gear cutting machine being provided with a workpiece spindle and a first tool spindle, and with an arrangement structure for chamfering according to claim 13 or 14, the workpiece spindle being arranged at a first machine position, and the first tool spindle being for rotationally driving a gear cutting tool to generate or machine gear teeth on a workpiece clamped on the workpiece spindle.

16. The hobbing machine according to claim 15, wherein the hobbing machine specifically has a coaxial first workpiece spindle axis and a second workpiece spindle axis of a reloading system and a linear movement axis extending parallel to both, and the reloading system transfers the workpiece from the first workpiece spindle to the second workpiece spindle.

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