Device and method for grinding a gear pair

Abstract

The present invention relates to an apparatus and a method for grinding a gear pair. A grinding method comprises: a) specifying a target correction for a pair of two gears of a first gear pair from a certain number of structurally equivalent gear pairs, b) implementing a first grinding procedure for the two gears of the first gear pair, c) implementing a measurement procedure for the two gears of the first gear pair to obtain a plurality of measurement values ​​on the tooth flanks of the two gears, d) determining an actual correction of the first gear pair based on the measurement values, e) determining a deviation of the actual correction relative to the target correction, f) determining a correction value based on the deviation, g) defining an adjusted grinding procedure based on the correction value, and h) implementing a further adjusted grinding procedure for the two gears of the first gear pair, or i) implementing an adjusted grinding procedure for the two gears of a second gear pair from the number of structurally equivalent gear pairs. The present invention also relates to an apparatus.

Description

Technical Field

[0001] The subject matter of the invention is a device and a method. In particular, the invention relates to a device and a method for grinding wheel sets. Background Art

[0002] Grinding methods are frequently used for hard finishing within the scope of bevel gear manufacturing. Grinding is a method for hard finishing (finishing after hardening) of the tooth flanks of bevel gear pairs (bevel gear units) or hypoid gear pairs (hypoid gear units). In contrast to gear cutting grinding, in which the abrasive grains are permanently bonded to the matrix of the grinding tool and the cutting path is therefore geometrically determined, grinding operates with loose particles that form a suspension with a suitable carrier liquid (called grinding liquid or abrasive). The purpose of introducing the abrasive is to grind into the meshing area between the gears of the wheel set in such a way that - under the provision of a certain torque load - abrasive removal is caused between the two gears. At the same time, grinding ensures the running-in of the gears of the wheel set.

[0003] The implementation of the grinding method on bevel and hypoid gears requires a special machine structure with a corresponding axis arrangement, wherein such a grinding machine has at least five axes that can be moved (e.g. three linear axes and two rotary axes). In addition, the grinding machine can have an axial angle adjustment.

[0004] Figure 1 A top view of an exemplary grinding machine 10 is shown in a greatly simplified form in FIG. The grinding machine 10 comprises, for example, a first spindle 11 for receiving a crown gear T, wherein the crown gear T is mounted so that it can rotate about a crown gear axis TA in a clamped state. In addition, there is a second spindle 12, which is designed to receive a pinion R. The second spindle 12 enables the pinion R to rotate about a pinion axis RA.

[0005] pass Figure 1 The grinding machine 10 shown by way of example in FIG. 1 has a total of five axes to realize the meshing rotation and displacement required for grinding (for shifting the grinding area) between the pinion R and the crown gear T. In total, the following five axes are provided in the grinding machine 10 shown: two rotation axes TA, RA for meshing rotation and three linear axes LA1, LA2, LA3. The axes can also be arranged differently.

[0006] Figure 1 The grinding machine 10 is capable of a relative movement parallel to the crown gear axis TA and a relative movement parallel to the pinion axis RA. In addition, the distance between the crown gear axis TA and the pinion axis RA can usually be adjusted (for example, by using the LA3 linear axis). The corresponding linear displacement is also used to adjust the installation dimensions of the wheel set to be ground.

[0007] After the crown gear T has been fastened to the first spindle 11 and the pinion R to be matched therewith has been fastened to the second spindle 12 in such a grinding machine 10, as Figure 1 , the pinion R is usually driven and the crown gear T is run along or braked accordingly when meshing with the pinion R. When the two gears T and R thus perform a continuous meshing rotation, a grinding agent (for example, oil with silicon carbide) is used as an abrasive. The mentioned movements are performed during the grinding process to extend the grinding action to the tooth flank surfaces of both gears T and R.

[0008] The producers of grinding machines offer machines which differ from one another substantially by means of differently designed relative movements. Some grinding machines can perform three linear movements, of which two horizontal movements LA1, LA2 are necessary, since otherwise the displacement of the pinion R would very quickly lead to consumption of the tooth flank play and to jamming if the crown gear T was not moved accordingly. The grinding of hypoid gear units requires a vertical axis LA3 for setting the axial offset, which of course can also be used for the wear pattern displacement during grinding.

[0009] A device is known from the published patent application EP2875893A1, which is designed as a testing machine and a grinding machine. The device comprises three linear axes LA1, LA2, LA3, which together form a Cartesian coordinate system. In addition, the device comprises two spindle groups, each of which has a spindle rotation axis.

[0010] Another grinding machine and a method for monitoring controlled grinding are known from patent EP 2 079 556 B1.

[0011] The simultaneous machining of the two gears increases the productivity of the method. However, grinding shows a significant dependence of the removal effect on the starting geometry of the gears after hardening.

[0012] In the milling and grinding of gears, the microgeometry to be generated by the computer can be determined and the milling and grinding methods can be controlled accordingly, for example in a closed-loop manner. In contrast, in grinding, the removal effects and the microgeometry of the tooth flanks of gears could hitherto only be accurately predicted to a limited extent.

[0013] This is because, among other things, there is a whole series of variables in grinding (e.g. surface hardness of the tooth flank, current topology of the tooth flank after hardening, concentration, size and quality of the particles of the abrasive, lubricating effect of the abrasive, etc.) which have a direct or indirect influence on the removal rate. In addition, it is necessary to take into account that the removal rate varies from point to point due to dynamic influences. Furthermore, the material removal on the pinion is greater than on the crown wheel because the pinion has fewer teeth.

[0014] Methods exist for calculating abrasive grinding processes, such as occur during gear cutting grinding, but an exact calculation or technical simulation of the process has hitherto not been possible, particularly since there are many non-linear relationships that must be taken into account.

[0015] Therefore, the machine operator's experience still plays a large role in gear cutting and grinding today. Summary of the invention

[0016] The object of the present invention is to make gear cutting grinding of a gear pair more efficient and to enable gear cutting grinding to be used in a more controlled manner.

[0017] The invention provides a grinding method and a corresponding device.

[0018] In at least part of the embodiments, the present invention is based on a novel closed-loop method, in which a first gear pair including a pinion and a crown gear is ground in a first pass. This first pass is used to achieve an ease-off of the gear pair, which corresponds to a target correction or approaches the target correction within a tolerance. The tooth flanks of the gear pair are measured after grinding so that the actual correction can be determined by computer and / or analytically. Possible deviations of the actual correction from the target correction are used to perform a correction or compensation of the grinding procedure in order to further grind the first gear pair, or to perform a correction or compensation of the grinding procedure previously used for grinding in order to grind another gear pair. Further grinding of the first gear pair is only performed if the first gear pair has a sufficiently large oversize after the implementation of the first grinding procedure. In the absence of a sufficient oversize, it is not reasonable to grind the first gear pair again.

[0019] In at least some of the embodiments, the invention is based on a closed-loop method, which can be considered as a self-optimizing system within certain limits. However, the principle of self-optimization has certain limitations in grinding, since grinding can only achieve small material removals and since grinding is always based on empirically determined values ​​and / or values ​​based on simulations. In addition, grinding always involves the pairing of two gears. However, since the invention is based on the provision of a target correction and a comparison with the actual correction, the advantages of the closed-loop method can also become useful here.

[0020] The method of the invention is a closed loop method, wherein the method is controlled and / or influenced in such a way that convergence in the direction of a desired target correction occurs rapidly during the grinding of at least one gear pair or during the grinding of a plurality of gear pairs of a group of structurally identical pairs.

[0021] Bevel and hypoid gear pairs that are identical in design are referred to herein as structurally identical gear pairs. This means that these are theoretically identical gear pairs. However, due to variations during the manufacture and handling of the gear pairs, the gear pairs are not actually identical. These are, for example, gear pairs that are manufactured in batches or mass production.

[0022] In at least some embodiments, the target correction can be used to define a set of structurally equivalent gear pairs. Gear pairs in the set are considered structurally equivalent if they - viewed separately as a pair - have identical or nearly identical wear patterns.

[0023] At least some of the embodiments relate to the grinding of bevel gear pairs and hypoid gear pairs. In particular, the embodiments relate to the grinding of structurally equivalent bevel gear pairs and structurally equivalent hypoid gear pairs.

[0024] In at least part of the embodiments, the present invention is based on a closed-loop method in which a first grinding procedure is intentionally controlled by using a removal variable (e.g., in the form of a removal coefficient). The removal variable defines the removal behavior of the grinding. By using the method of the present invention, a correction that approaches the target correction within tolerance can already be achieved for the first gear pair after grinding. In some cases, after implementing the first grinding procedure, it is necessary to implement a second adjusted grinding procedure to achieve the target correction.

[0025] After grinding, the tooth flanks of the gear pair are measured in order to determine the actual correction by computer and / or analytically. Possible deviations of the actual correction from the target correction are then used to correct or compensate for the further grinding of the gear pair or for the grinding of another gear pair. Thus, the grinding can be controlled in such a way that the actual correction is kept as close as possible to the target zone defined by the target correction.

[0026] In at least one part of the embodiments, within the scope of an iterative method designed for grinding at least one gear pair of a plurality of structurally identical gear pairs, a target correction and an actual correction of a first gear pair are used to enable a corrective and targeted intervention in the grinding method of the first gear pair (if the pair has a sufficiently large oversize after a first grinding procedure to implement a second adjusted grinding procedure) or in the grinding method of a second gear pair. Such intervention results in a rapid convergence of the method.

[0027] The method of the invention is based on the definition of interventions on two gears when they are mated to each other. As described, this intervention is described on the basis of corrections. Furthermore, the invention is based on finishing the tooth flanks by means of a grinding routine that is continuously corrected in a closed-loop method. In this closed-loop grinding method, no finishing tool is used, but rather the two gears are rolled on each other using an abrasive to achieve the target correction.

[0028] At least a portion of the embodiments is based on a removal behavior or respectively a removal rate or removal work previously determined empirically and / or by simulation. The removal behavior can be determined empirically, for example, because the grinding method is implemented and analyzed on multiple wheel sets. For example, if the grinding method is repeatedly implemented, the speed and braking torque can be obtained for multiple points in the point set, wherein the relative position of the two gears of the wheel set is changed when implementing the grinding method and the relative position of the corresponding points is also obtained. This means that the speed and braking torque are obtained and stored for changing the relative position.

[0029] In all embodiments, the removal behavior or respectively the removal rate or the removal work can be determined and stored in the form of a removal variable, for example in the form of a removal coefficient.

[0030] When determining the removal behavior, for example, the braking torque at the corresponding point can also be determined, since this torque has a significant influence on the removal work or the removal rate.

[0031] When determining the removal behavior, for example, the velocity at the respective point can also be determined, since this has a significant influence on the removal work or the removal rate.

[0032] In at least some of the embodiments, a removal variable (eg, in the form of a removal coefficient) is used to enable a corresponding milling procedure to be implemented in an NC-controlled manner.

[0033] In at least some of the embodiments, removal variables (eg, in the form of removal coefficients) are used to enable simulation of a corresponding milling schedule in a software-controlled manner (eg, within the context of an inverse simulation of the milling schedule).

[0034] In at least one part of the embodiments, topological data are provided before grinding (these data can be loaded from a database, provided by software, or they can be measured by a measuring device - for example, by a coordinate measuring device). In addition, topological data are determined after grinding (these data can be measured by a measuring device). These topological data are related to each other, that is, these topological data are relatively positioned with respect to each other, so that the difference (herein referred to as deviation) between the target correction and the actual correction of multiple points in the point set can be determined by computer and / or analytically.

[0035] In the case of the mentioned making the topological data related to each other, at least part of the embodiment is based on points that are also incorporated that do not change during grinding. In this case, these can be, for example, (fixed) points in a point set, which are located in such an area of ​​the corresponding gear that the relative gear has not reached during grinding. In these capable embodiments, these (fixed) points, which are not removed during grinding, are used to be able to put the topological data before grinding in a clear relationship with the topological data after grinding. For example, the topological data before grinding can be provided at the points of the first measurement grid, and the topological data after grinding can be provided at the points of the second measurement grid. The first measurement grid can now be placed in a clear spatial relationship with the second measurement grid, because both measurement grids include (fixed) points that do not change during grinding. Therefore, the actual geometry of the two gears before grinding (also called the starting geometry or starting topology) can be clearly related to the geometry of the two gears after grinding, and the correction before grinding and the correction after grinding can be calculated.

[0036] In such embodiments, the starting geometry or starting topology may be imported, for example, from a database or (design) software. However, it may also be measured (for example, by a measuring device).

[0037] At least a portion of the embodiments enables a target correction to be specified for a plurality of structurally identical bevel or hypoid gear pairs and a monitored NC-controlled grinding method to be implemented, e.g., to produce an actual correction from a first pair or, e.g., from a second pair, which corresponds to the target correction or is within a tolerance range that can be considered a target zone.

[0038] In at least a portion of the embodiments, a grinding procedure is used, the sequence of which is fully defined. The definition of the grinding procedure includes establishing multiple relative positions, moving one gear relative to another gear, and maintaining (if maintenance is provided) in various relative positions. In addition, it is determined which gear's tooth flank is in contact with the tooth flank of the relative gear and which gear is driven and which gear is braked. That is, in the grinding procedure, relative positions (called relative positioning), paths between these positions, and torque loads are defined. The grinding procedure can therefore be reproduced again and again and in this way direct comparability of the results can be achieved.

[0039] In embodiments based on the use of a reproducibly implemented grinding routine, for example, corrections or compensations can be applied to the linear movement of one gear relative to another gear, and / or corrections or compensations can be applied to the hold durations held at various relative positions. Corrections or compensations can also be applied additionally or alternatively to torque loads.

[0040] The present invention also provides preferred embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Further details and advantages of the invention are described below on the basis of exemplary embodiments and with reference to the drawings.

[0042] Figure 1 shows a schematic top view of a conventional grinding device designed to mesh a pinion and a crown gear and cause them to roll on each other;

[0043] Figure 2 A schematic side view of a closed-loop device of the present invention is shown, the closed-loop device comprising a grinding device and a measuring device;

[0044] Figure 3A A schematic diagram showing an embodiment including software as a central element;

[0045] Figure 3B A schematic diagram showing an embodiment including a plurality of software components or modules;

[0046] Figure 4A A schematic diagram showing several steps of an embodiment of the method in the form of a flow chart;

[0047] Figure 4B Shows Figure 4B Schematic diagram of the other steps of the method. DETAILED DESCRIPTION

[0048] The terms are used in conjunction with this specification and are also used in related publications and patents. However, it should be noted that the use of these terms is only for better understanding. The scope of protection of the inventive concept and the claims for protection is not limited to the interpretation made by the specific selection of terms. The present invention can be easily transferred to other terminology systems and / or technical fields. The terms are applied accordingly in other technical fields.

[0049] Grinding here means the mutual meshing rotation of two transmission elements (e.g. a crown wheel Tn and a pinion Rn, where n is an integer greater than or equal to 1), wherein contact occurs in the meshing area between the tooth flanks of the transmission elements Tn and Rn, and wherein a grinding agent is introduced so that mutual material removal occurs on the transmission elements Tn and Rn. The device for introducing the grinding agent is not shown in the figure, since such solutions are known to the person skilled in the art. Such grinding of bevel gear teeth is also considered to be known.

[0050] The invention relates to a closed-loop method for grinding one or more gear pairs based on a previously defined target correction. In this case, the target correction serves as a quasi-target specification or target zone.

[0051] The correction of a gear pair results from the interaction and / or rolling of the tooth flank topology of the gear and the counter gear. The correction is defined as the global minimum of the distance function between the gear and the counter gear as they roll past each other at a predetermined constant transmission ratio (e.g. using the following tooth numbers Z1=18, Z2=45, resulting in a transmission ratio = 45 / 18=2.5). The correction can also be considered as a representation of the tooth flank distance of the gear pair. The correction is usually determined for a number of points on the tooth flanks of the two gears Tn, Rn of the gear pair.

[0052] In all embodiments, the software-aided design method (for example, using KIMoS from Klingelnberg GmbH) can be used. TM software) to calculate / establish target corrections for gear pairs, e.g. during wear pattern development.

[0053] In all embodiments, a target correction of a gear pair can be established by a number of parameters, including, for example, helix angle difference, flank angle difference, longitudinal and / or vertical crowning, and twist.

[0054] Grinding may be intentionally controlled in grinding device 100 by an NC controller via a closed loop method, which is described and claimed herein.

[0055] During the rolling of the teeth of the bevel pinion and crown gear of the bevel gear pair, sliding occurs in the tooth vertical direction during grinding. In the gears of the hypoid gear pair, sliding in the tooth longitudinal direction is superimposed on sliding in the tooth vertical direction. The local relative speed of the contact points in the point set can be calculated from these sliding movements. This means that if the geometry of the gears and the rotation speeds about the rotation axes TA and RA are known (which is the case in NC-controlled grinding devices 100), the relative speed acting at the contact points can be determined by computer. This relative speed is a variable that can be incorporated into the determination of the local removal rate.

[0056] However, the relative speed of the contact tooth flanks only describes one aspect of grinding. In addition, for example, the grinding effect of the particles of the abrasive is also determined and taken into account. In this case, the tooth flanks of the two gears Tn, Rn must be considered as workpieces and tools in the grinding process at the same time. It is necessary to take into account that there are various removal mechanisms in grinding (e.g., cutting removal behavior and plowing removal behavior), which are superimposed here. Depending on the dominant removal mechanism, different removal appearances and removal rates can therefore be expected, i.e. different removal rates within the scope of the grinding method.

[0057] In this case, there is a whole series of variables (e.g. surface hardness of the tooth flank, current topology of the tooth flank after hardening, concentration, size and quality of the particles of the abrasive, lubricating effect of the abrasive, etc.) which have a direct or indirect influence on the removal rate. In addition, the removal rate varies from point to point due to dynamic influences.

[0058] The invention is based on a method, which is referred to herein as an iterative closed-loop method. In this iterative method, a first wheel set is ground within the scope of a method sequence by means of a previously defined first grinding schedule. This wheel set is then measured to determine the actual correction by computer and / or analytically. If this actual correction does not correspond to the desired target correction, or if the actual correction is outside the tolerance window of the target correction, a correction or compensation value KW is therefore determined for subsequent further grinding of the first wheel set or for subsequent grinding of another wheel set. In all embodiments, these correction or compensation values ​​can be used, for example, to adjust the first grinding schedule (the adjusted first grinding schedule is referred to herein as the adjusted grinding schedule or as the second grinding schedule).

[0059] The adjustment of the grinding schedule can be performed iteratively before the grinding of each wheel set, or can be adjusted from time to time. In the stable state of the method of the invention, it is sufficient to adjust the grinding schedule after every 10th wheel set pair, for example.

[0060] In the context of a method, for example, you can use the combination Figure 1 The device 10 is described. Figure 2 The device 10 is shown (here shown as an example in the interior of a machine housing 13) and a measuring device 20. The device 10 together with the measuring device 20 forms an integral configuration which is referred to as a closed-loop device 100. This means that the two devices 10, 20 are communicatively connected to one another in such a way that, for example, a measured value MW determined in the measuring device 20 can be transferred to the device 10. The communication connection has the reference numeral 14 here and is indicated by a double arrow. In addition, Figure 2 4 shows a control cabinet 40, which may contain, for example, an NC controller NC of the device 10. Software SW (and / or software or software modules SW1, SW2) designed, for example, to implement the method of the present invention may be provided in the control cabinet 40 or at another location of the device 100. In all embodiments, the software SW is preferably integrated into the communication between the two devices 10, 20.

[0061] Arrow 15 indicates the transfer of the gear pair out of the device 10 to the measuring device 20. In all embodiments, this transfer 15 can be performed manually, semi-automatically or fully automatically.

[0062] In all embodiments, the grinding device 10 may comprise a data interface or user interface SN which makes it possible to define the removal variables, in particular the grinding coefficient αL.

[0063] In all embodiments, one of the following methods may be implemented:

[0064] The calculation of the grinding setting and / or correction is carried out on an external computer, to which the grinding factor αL must be supplied;

[0065] - performing a calculation on the grinding device 10 , wherein the grinding coefficient αL must be provided to the grinding device 10 ;

[0066] The calculation of the correction is carried out on the measuring device 20 , wherein the measurement coefficient α L must be provided to the measuring device 20 .

[0067] For example, details about the simulation and determination of the removed variables can be inferred from the following publication: "Experimental studies and simulation of hypoid gear lapping", B. Schlecht, F. Rudolph, International Conference on Gear Production 2017, 13-14 September 2017, Garching bei Munich.

[0068] The grinding device 10 and the measuring device 20 can be coupled to each other, as indicated by the double arrow 14. The term coupled is used to indicate that the machine 10 and the measuring device 20 are coupled at least with respect to communication (i.e., for data exchange). This communication coupling (also called networking) presumes that the machine 10 and the measuring device 20 understand the same or compatible communication protocol and that both follow certain conventions regarding data exchange. For data exchange, for example, software or a software module SW2 can be used, as will be described below.

[0069] The term coupled may also mean that the machine 10 and the measuring device 20 are not only networked, but also mechanically connected or fully integrated with each other. In all embodiments, the measuring device 20 may be integrated into the machine 10 or directly connected to the machine.

[0070] In all embodiments, the machine 10 and the measurement device 20 may form a closed processing and communication loop (referred to as a closed loop).

[0071] In all exemplary embodiments, the individual axes of the machine 10 and / or the individual axes of the measuring device 20 can be controlled, for example, by a common NC controller, which can be arranged, for example, in a control cabinet 40 .

[0072] However, in each case, separate NC controllers may also be provided in the machine 10 and the measuring device 20. In this case, networking for data exchange may be established, for example, between the NC controllers (eg, via a network).

[0073] In all exemplary embodiments, the machine 10 and / or the measuring device 20 can be controlled, for example, by means of a common software SW, which can be installed, for example, in a control cabinet 40 .

[0074] The axes controlled by the NC controller are numerically controlled axes. The individual axis movements can be digitally controlled by the NC controller through this constellation. It is important that the individual movements of the axes of the machine 10 are performed during grinding, as established based on a sequence or sequence program for the grinding procedure. Therefore, the movements of the axes of the machine 10 can be performed in a coordinated and reproducible manner. In all embodiments, the coordination of such movements can be performed by the NC controller 40 and / or the software SW.

[0075] Use suitable software or software module SW1 (for example, the software KIMoS from Klingelnberg GmbH, Germany) TM ) is used to specify a target correction for a gear pair (referred to herein as gear pair Tn, Rn). The software or software module SW1 can provide the target correction, for example at the end of the design process, in the form of a data set, which can be organized, for example like a matrix. The data set defines in principle the pairing of a crown gear T1 and a pinion gear R1. The machine kinematics for the grinding of the two gears T1, R1 required for this purpose can be determined based on the data set. The grinding of the two gears T1, R1 of the first gear pair is referred to herein as the first grinding procedure. The machine kinematics of the first grinding procedure can be determined or calculated, for example, by simulation based on a (data) model of the machine 10 to be used and using removed variables (e.g. in the form of removed coefficients).

[0076] Since there are other methods of defining a target correction of the first gear wheel pair, the general term definition data VD is used below for the corresponding data, wherein these definition data VD precisely define the meshing of the two gear wheels T1 , R1 when they are paired with each other.

[0077] In all embodiments, the prescribed data VD can also describe the machine kinematics (wherein, for example, the set values ​​of the grinding device 10 are determined based on a model of the grinding device 10 to be used) or the machine kinematics can be provided in the form of an additional (separate) data set.

[0078] For example, these prescribed data VD can be transferred to a process. The process, which can be implemented, for example, as software or a software module, can in this case convert the prescribed data VD into machine data MD (sometimes also called machine code or process data), which is converted by the NC controller of the machine 10 into a coordinated movement sequence.

[0079] The machine 10 now grinds the two gears T1, R1, for example as specified on the basis of the machine data MD for the first grinding routine. After this grinding operation has been completed, the two gears T1, R1 are transferred (directly or indirectly) to the measuring device 20 (as indicated by the arrow 15). A predefined measurement sequence is performed in the measuring device 20 and a relative axial movement of the NC axes of the measuring device 20 is performed within the scope of this measurement sequence to obtain measured values ​​MW, which are suitable for determining the actual correction. The determination of the actual correction can be performed, for example, directly in the measuring device 20 or, for example, by software or a software module SW2.

[0080] Figure 3A An embodiment is shown in which all functions are implemented in software SW. For example, the software SW can be used to determine the actual correction from the measured value MW provided by the measuring device 20. The software SW can calculate the correction value or compensation value ΔMD from the actual correction and the target correction contained in the specified data VD. In an optional intermediate step, a deviation ΔVD can be calculated and provided.

[0081] Figure 3B An embodiment is shown in which the software SW is linked to two software modules SW1 and SW2. The software module SW2, if provided, can be used to determine the actual correction, for example, from the measured value MW provided by the measuring device 20. The software SW can compare the actual correction with the target correction contained in the prescribed data. The software module SW1, if provided, can be used to calculate the correction value or compensation value ΔMD, for example, from the result of the comparison performed by the software ΔSW. In an optional intermediate step, a deviation ΔVD can be calculated and provided.

[0082] Figure 3A and Figure 3B The schematic diagrams are to be understood as examples. There are other options for organizing the data transfer as well as the calculation and conversion steps.

[0083] For example, the software KOMET from Klingelnberg GmbH in Germany TM An optimization algorithm can be used to convert the measured value MW determined by the measuring device 20 into a correction of the grinding program to be performed thereafter (eg in the form of a correction value or compensation value ΔMD).

[0084] In an ideal case, the actual correction of the two gears T1, R1 is exactly the same as the target correction, i.e. the actual data ID corresponds to the prescribed data VD. In this case, which is of theoretical interest only, the machine data MD can be stored, for example, to grind further structurally identical gear pairs (e.g. in series).

[0085] However, in practice, a deviation (herein referred to as ΔVD) between actual data ID and prescribed data VD or, respectively, between a target correction and an actual correction is determined during measurement.

[0086] In at least some of the embodiments, these deviations ΔVD may be provided directly or indirectly to the software SW and / or the NC controller of the machine 10 , for example via the measuring device 20 .

[0087] Depending on the embodiment, for example, the software SW and / or the NC controller can now determine correction values ​​ΔMD for controlling the machine 10 and transmit them to the machine 10. However, the software SW and / or the NC controller can also determine the deviation ΔVD and / or the correction value ΔMD from the measured values ​​provided by the measuring device 20.

[0088] The correction value ΔMD is taken into account during the further grinding of the first gear pair or during the grinding of the subsequent gear pairs. For example, the correction value ΔMD can be linked to the machine data MD of the first grinding routine in order to adjust the sequence control of the subsequent grinding routine. Alternatively, new machine data MD for the sequence control of the subsequent grinding routine are calculated based on the correction value ΔMD.

[0089] In all exemplary embodiments, the mentioned deviation ΔVD is preferably used to adjust geometrical setpoints and / or movements of the machine 10 .

[0090] The described closed-loop method as well as other network solutions of similar type enable the step-by-step optimization of corrections in the grinding of structurally identical gear pairs.

[0091] In all exemplary embodiments, the software SW and / or SW1 and / or SW2 may include at least one (hardware and / or software) interface which is designed for data communication with the machine 10 and / or the measuring device 20 .

[0092] In all embodiments, the software SW and / or SW1 and / or SW2 may be designed to calculate correction values ​​ΔMD from measured values ​​MW describing the actual correction and from values ​​describing the target correction (eg from corresponding prescribed data VD).

[0093] In all embodiments, these correction values ​​ΔMD can be calculated directly from the actual corrected measured value MW and the target corrected value (e.g. from the corresponding prescribed data VD), or first the deviation ΔVD is calculated from the measured value MW and the value (e.g. from the corresponding prescribed data VD). In the latter case, the calculation of the correction value ΔMD is then performed as a function of the deviation ΔVD.

[0094] In at least one part of the embodiment, the network processing environment (herein referred to as the closed-loop device 100) is designed to implement the following method. In this case, the following steps are performed.

[0095] A target correction of the pairing of two gear wheels of a first gear wheel pair T1 , R1 from a number n of structurally identical gear wheel pairs Tn, Rn, wherein n is an integer greater than or equal to 1, is specified or provided (step S1 ).

[0096] For example, Figure 4A As indicated, the target correction may be provided in the form of provision data VD. In all embodiments, the provision or provision of the target correction (step S1) or the corresponding provision data VD may for example be:

[0097] - calculated / established within the scope of software-aided design methods, as already described, or

[0098] - after hardening of the already cut gear pair, a measurement of the actual geometry / actual topology of both gears of the gear pair can be performed and then a target correction can be established based on the actual geometry / actual topology, or

[0099] - For example, target corrections can be loaded from memory, or

[0100] The target correction is established / defined by determining the effect of grinding on the basis of the inverse simulation. The geometry / topology of the two gears after hardening (i.e. before grinding) can be determined by inverse simulation. In addition, it can be determined how the geometry / topology of the two gears appears after gear cutting (e.g. by milling). If the geometry / topology of the gears after cutting and / or the geometry / topology after hardening are known, a suitable target correction can be established / defined for the gear pair.

[0101] A first grinding routine is then carried out on the two gears of the first gear pair T1, R1 (step S2). The individual NC-controlled movements of the axes of the machine 10 are carried out within the scope of the first grinding routine as established on the basis of a sequence or sequence program. For example, the software SW can interact with an NC controller of the machine 10, wherein the software SW transmits machine data MD to the NC controller, such as Figure 4A Indicated schematically in FIG.

[0102] In all embodiments, before implementing the first grinding procedure (step S2), the following preparatory steps may be optionally implemented:

[0103] - clamping the first gear wheel T1 of the gear wheel pair T1 , R1 in the grinding device 10 so that the first gear wheel T1 can rotate about the first rotation axis TA of the grinding device 10 ,

[0104] - clamping the second gear R1 of the gear pair T1, R1 in the grinding device 10 so that the second gear R can rotate about the second rotation axis RA of the grinding device 10,

[0105] - performing a relative movement by means of the grinding device 10 so as to mesh the first gear wheel T1 with the second gear wheel R1,

[0106] - Introducing the grinding medium into the grinding device 10 .

[0107] After step S2, the two gears of the first gear pair T1, R1 are subjected to a measuring procedure. The implementation of the measuring procedure (step S3) is carried out in such a way that a plurality of measured values ​​MW are acquired on the tooth flanks of the two gears. The implementation of the measuring procedure (step S3) can be carried out in the machine 10 or in the measuring device 20. If step S3 is carried out inside the machine 10, the gears T1, R1 do not have to be re-clamped. If step S3 is carried out in a separate measuring device 20, the gears T1, R1 must be transferred to the measuring device 20 beforehand, e.g. Figure 2 As shown by arrow 15 in FIG.

[0108] The actual correction of the first gear wheel pair T1, R1 is now determined based on the measured value MW (step S4). In all embodiments, the determination of the actual correction can be performed by computer and / or analytically. In all embodiments, software SW and / or SW2 is preferably used, which enables the actual correction to be determined based on the measured value MW, which is measured after grinding the first gear wheel pair T1, R1.

[0109] Step S4 can be implemented at various points throughout the device 100, as has been previously described on the basis of various embodiments. In all embodiments, the actual correction can be described, for example, in the form of an actual data ID.

[0110] The actual correction is now compared with the target correction (step S5). The comparison is used to determine the deviation between the actual correction and the target correction. In all embodiments, the determination of the deviation can be performed by computer and / or analytically. In all embodiments, software capable of calculating the deviation is preferably used.

[0111] If the actual correction is already within the tolerance window (which is defined as, for example, the target correction ± the tolerance value), the iterative method can be terminated and the next gear pair T2, R2 in the set of structurally identical gear pairs Tn, Rn can be subjected to steps S2 to S5. This back branch of the method is Figure 4A In this particular case, the first gear pair T1, R1 may have been output at the end of step S5, as shown in FIG. Figure 4A The path 17.1 is schematically shown.

[0112] However, if the actual correction is outside the tolerance window, the steps described below are performed.

[0113] The following steps are Figure 4B Shown in.

[0114] Then the correction value is determined (step S6). Within the determined range, the correction value can be expressed in the form of a change and / or adjustment of the specified data VD. In all embodiments, the determination of the correction value can be performed by computer and / or analytically. In all embodiments, software including an optimization algorithm is preferably used.

[0115] The correction value is referred to here as ΔVD. Within this defined range, the correction value ΔVD is expressed in the form of a change and / or adjustment of the machine data MD. In this case, the correction value is referred to as ΔMD.

[0116] In the following step S7 , a second (adjusted) grinding schedule is defined based on the correction value ΔVD or ΔMD.

[0117] exist Figure 4B In the embodiment, the implementation of the second (adjusted) grinding procedure also has the reference sign S2* to indicate that in all embodiments, the second (adjusted) grinding procedure can be defined by the adjustment of the first grinding procedure (step S2) or can be derived therefrom.

[0118] In order to carry out the second grinding routine (step S8 ), machine data MD* can be determined based on the correction values ​​ΔVD or ΔMD, for example, and transmitted to the machine 10 .

[0119] If the actual correction of the first gear pair T1, R1 is not yet within the tolerance window (which is defined as, for example, the target correction ± the positive tolerance value) (this is determined within the scope of the comparison in step S5), the first gear pair T1, R1 can be subjected to a further adjusted grinding procedure ( Figure 4B The adjusted / corrected machine data MD* are used for this further adjusted grinding procedure.

[0120] However, it is only advisable to carry out a further adjusted grinding procedure on the first gear pair T1 , R1 if both gears T1 , R1 have a sufficiently large overdimension after the first grinding procedure.

[0121] If the first gearwheel pair T1 , R1 is not subjected to a further adjusted grinding procedure, the gearwheels of the second gearwheel pair T2 , R2 are therefore introduced into the machine.

[0122] Before carrying out the adjusted grinding procedure on the second gear pair T2 , R2 (step S8 ), in all embodiments, preliminary steps can be carried out on both gears T2 , R2 , which have been described in connection with step S2 based on the first gear pair T1 , R1 .

[0123] At the end of step S8, the corresponding gear pair (for example, the first gear pair T1, R1 after two grindings or the second gear pair T2, R2 after one grinding) can be output, as shown in FIG. Figure 4B The path 17.2 is schematically shown.

[0124] Optionally, the measurement can be performed again in a downstream step S9 in order to obtain measured values ​​which enable the actual correction of, for example, the second gear pair T2, R2 to be calculated and checked. The measurement procedure already described for step S3 can be used here. This optional step S9 can be always performed to determine whether the actual correction is now within the tolerance window of the target correction. However, it is also possible to implement step S9 only from time to time (for example, for every 10th gear pair). If the actual correction is within the tolerance window, the second gear pair T2, R2 can therefore be output, such as Figure 4B The path 18 in FIG. 1 is schematically shown.

[0125] If the method has not converged during the grinding of the first gear pair T1, R1 or the second gear pair T2, R2, these steps can optionally be repeated for a further gear pair Tn, Rn. This further back branching of the method is accomplished by Figure 4A , Figure 4B The path 19 in FIG. 1 shows. The method can also branch back to start at step S8, such as Figure 4B As indicated.

[0126] In order to be able to perform grinding in a targeted manner within the scope of the method, in all embodiments, the removal behavior of the grinding device 10 during grinding can be taken into account. The removal behavior can be determined empirically, for example, based on previous grinding attempts on structurally identical gear pairs, and stored. For example, the removal behavior can be determined by simulation and stored.

[0127] Preferably, the instantaneous load torque and / or the speed and / or the holding time are acquired for a plurality of points on the tooth flanks of the crown wheel Tn and the pinion wheel Rn during the determination of the removal behavior (if the grinding procedure provides for the holding of the relative movement of the corresponding points). In addition, for example, the coordinates of the corresponding points are acquired in three-dimensional space. Thus, an array of parameters and / or values ​​can be acquired and stored per point. Thus, a removal variable, for example in the form of a grinding coefficient αL, can be acquired and stored per point.

[0128] The relative travel path from point to point (which it travels due to the relative displacement of the crown wheel Tn and the pinion wheel Rn in the machine 10 ) and one or more method-related parameters or values ​​for grinding may also be acquired during the determination of the removal behavior.

[0129] The removal coefficient αL optionally determined for a plurality of points enables statements to be made about the local grinding removal at each individual point. In addition, statements can also be made about the distribution of the grinding removal on the tooth flank of the gears Tn, Rn based on a set of removal coefficients αL. Grinding can be intentionally controlled by the NC controller of the device 10 based on the removal coefficients αL.

[0130] Reference numerals list

[0131]

[0132]

Claims

1. A grinding method comprising the following steps: a) specifying (S1) a target correction of a pair of two gears from a first gear pair (T1, R1) of a certain number (n) of structurally identical gear pairs (Tn, Rn), b) performing (S2) a first grinding procedure on the two gears of the first gear pair (T1, R1), c) carrying out (S3) a measurement procedure on the two gears of the first gear pair (T1, R1) to obtain a plurality of measured values ​​(MW) on the tooth flanks of the two gears, d) determining (S4) an actual correction of the first gear pair (T1, R1) based on the measured value (MW), e) determining (S5) a deviation of the actual correction relative to the target correction, f) determining ( S6 ) a correction value (ΔVD; ΔMD) based on the deviation, g) based on the correction value (ΔVD; ΔMD) defines (S7) the adjusted grinding schedule, as well as h) performing a further modified grinding procedure (S8, S2*) on the two gears of the first gear pair (T1, R1), or i) carrying out an adapted grinding procedure (S8, S2*) on two gears of a second gear pair (T2, R2) from said number (n) of structurally identical gear pairs (Tn, Rn), The correction is defined as the global minimum of the distance function between the gear and the counter gear as they roll past each other at a predetermined constant gear ratio.

2. The grinding method according to claim 1, characterized in that: Step h) is performed on the first gear pair (T1, R1) only if the first gear pair (T1, R1) has a sufficiently large oversize after the first grinding procedure has been performed (S2).

3. The grinding method according to claim 2, characterized in that: After step h), the first gear pair (T1, R1) is output.

4. The grinding method according to claim 1, characterized in that: After step i), a measurement procedure according to the provisions of step c) and a determination of the actual correction according to the provisions of step d) are performed on the second gear pair (T2, R2) to determine whether the second gear pair (T2, R2) is within a tolerance window of the target correction, wherein if the actual correction is within the tolerance window, the second gear pair (T2, R2) is output.

5. The grinding method according to claim 3, characterized in that: Steps b) to i) are carried out for the other gear pairs (Tn, Rn).

6. The grinding method according to any one of claims 1 to 5, characterized in that The target correction and the actual correction describe the meshing behavior of two gears of the gear pair (Tn, Rn) when they mesh while being paired with each other.

7. The grinding method according to any one of claims 1 to 5, characterized in that The correction is defined as a set with a plurality of discrete correction values ​​or as a correction function.

8. The grinding method according to any one of claims 1 to 5, characterized in that The target correction is determined in a preliminary step based on simulations or based on a calculation method, using removal variables that are available for a plurality of points on the tooth flanks of both gears of the gear pair (Tn, Rn).

9. The grinding method according to any one of claims 1 to 5, characterized in that The following preliminary steps are performed before step b) and / or before step i): - clamping a first gear wheel (Tn) of a gear wheel pair (Tn, Rn) in a grinding device (10) such that the first gear wheel (Tn) can rotate about a first rotation axis (TA) of the grinding device (10), - clamping the second gear wheel (Rn) of the gear wheel pair (Tn, Rn) in the grinding device (10) such that the second gear wheel (Rn) can rotate about a second rotation axis (RA) of the grinding device (10), - performing a relative movement by means of the grinding device (10) so as to mesh the first gear (Tn) with the second gear (Rn).

10. The grinding method according to claim 9, characterized in that: During the first and second grinding procedures carried out in the grinding device (10), the grinding medium is introduced in such a way that in the meshing region of the two gears (Tn, Rn), the abrasive particles of the grinding medium ensure material removal on the two gears (Tn, Rn).

11. The grinding method according to claim 8, characterized in that: The simulation is an inverse simulation.

12. The grinding method according to claim 8, characterized in that: The removal variable is the grinding coefficient (αL).

13. A device (100) comprising a grinding device (10) and a measuring device (20), wherein: - the grinding device (10) comprises a plurality of NC controlled axes (LA1, LA2, LA3, RA, TA) and an NC controller (NC), - the grinding device (10) is designed to carry out a first grinding procedure (S2) on two gears of a first gear pair (T1, R1), - the measuring device (20) is designed to carry out a measuring procedure (S3) on the two gears of the first gear pair (T1, R1) in order to obtain a plurality of measured values ​​(MW) on the tooth flanks of the two gears, - The device (100) is designed to: determining an actual correction of the first gear pair (T1, R1) according to the measured value (MW), determining the deviation of the actual correction from the target correction, Determine a correction value (ΔVD) based on the deviation; ΔMD), and Defining the adjusted second grinding procedure (S8, S2*), and wherein the grinding device (10) is designed to implement the adjusted second grinding procedure (S8, S2*) on the two gears of the first gear pair (T1, R1) and / or on the two gears of the second gear pair (T2, R2), The correction is defined as the global minimum of the distance function between the gear and the counter gear as they roll past each other at a predetermined constant gear ratio.

14. The device (100) according to claim 13, characterized in that The grinding schedule ( S2 , S8 ) can be defined by means of removal variables which are available for a plurality of points of the tooth flanks of both gear wheels of the respective gear wheel pair (Tn, Rn).

15. The device (100) according to claim 14, characterized in that The device comprises a data or user interface (SN) enabling the device to define the removal variable.

16. The device (100) according to any one of claims 13 to 15, characterized in that The grinding device (10) and the measuring device (20) are coupled in a communication manner.

17. The device (100) according to any one of claims 13 to 15, characterized in that The grinding device (10) and the measuring device (20) are integrated in such a way that between grinding the two gears of the gear pair (Tn, Rn) and carrying out a measuring procedure (S3) on the two gears of the gear pair (Tn, Rn), no re-clamping of the two gears is required.

18. The device (100) according to any one of claims 13 to 15, characterized in that The device comprises at least one software or at least one software module (SW, SW1, SW2), wherein the software or software module (SW, SW1, SW2) is designed to determine a deviation between an actual correction and a target correction and to perform an adjustment of a first grinding procedure (S2) in order to define the adjusted second grinding procedure (S8, S2*) therefrom.

19. The device (100) according to claim 14 or 15, characterized in that The removal variable is the grinding coefficient (αL).

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