Analysis of gear cutting process by means of rolling test
By converting gear cutting machine axial and sensor data to rotation-related data using FFT, correlations between rolling test results and machine analysis are established, facilitating error identification and reduction in gear manufacturing.
Patent Information
- Application Number
- JP2025010424
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-01-25
- Filing Date
- 2025-01-24
- Publication Date
- 2025-08-06
AI Technical Summary
Rolling test results from gear cutting machines are not directly comparable to data from gear cutting machine analysis, making it difficult to determine correlations between rolling test results and machine analysis, particularly due to kinematic deviations that affect gear geometry.
Record axial data and sensor data from the gear cutting machine during machining, convert them to rotation-related data using FFT, and compare with rotation-related measurement data from rolling tests to identify correlations between gear and machine deviations.
Enables direct comparison and identification of errors in gear cutting machines by correlating rolling test results with gear cutting machine data, allowing for targeted calibration and maintenance to reduce errors in subsequent gear manufacturing.
Smart Images
Figure 2025115395000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to a method comprising machining the gears of a part on a gear cutting machine and rolling testing the toothed part on a rolling test stand. [Background technology]
[0002] Due to the ever-increasing demands on the quality of gears, especially their noise behavior, in industrial series production, up to 100% of all manufactured gears are subjected to rolling tests on rolling test stands. This allows, among other things, the determination of periodic deviations that have a negative effect on the gear's noise behavior.
[0003] It is also known to record axis or sensor data from each gear cutting machine during the machining of the gears in order to monitor the functioning of the machine, its components and the manufacturing process itself. Such machine tool data is usually recorded as displacement or time signals. Summary of the Invention [Problem to be solved by the invention]
[0004] For example, kinematic deviations of the shaft or drive or gear cutting machine may be reflected in the rolling test results, as some of these deviations will be transferred to the geometry of the manufactured gear. Rolling test results are typically recorded relative to the rotation of the part during the rolling test. Rolling test results are not directly comparable to data from gear cutting machine analysis, making it difficult to determine correlations between rolling test results and data from machine analysis.
[0005] Against this background, the present invention is based on the technical problem of identifying a method that allows an efficient comparison of rolling test results with data from the analysis of gear cutting machines. [Means for solving the problem]
[0006] The above-mentioned technical problem is solved by the features of the independent claims. Further designs of the invention can be obtained from the dependent claims and the following description.
[0007] According to a first aspect, the present invention relates to a method comprising the steps of: machining a gear of a component by means of a gear cutting machine, wherein axial data of at least one machine axis of the gear cutting machine, such as axial feed, axial acceleration, power consumption of axial drives, are recorded during the machining of the gear and / or sensor data of at least one sensor of the gear cutting machine, such as a structure-borne noise sensor, an acceleration sensor, a distance sensor, etc., are recorded during the machining of the gear; providing the recorded axial data related to one revolution of the component as rotation-related axial data and / or providing the recorded sensor data related to one revolution of the component as rotation-related sensor data; rolling test the toothed component by means of a rolling test stand, wherein measurement data of the rolling test is provided as rotation-related measurement data related to one revolution of the component during the rolling test; and comparing the rotation-related axial data and / or the rotation-related sensor data with the rotation-related measurement data of the rolling test in order to determine a correlation between deviations of the gear according to the rotation-related measurement data of the rolling test and deviations of the machine according to the rotation-related axial data and / or the rotation-related sensor data.
[0008] The fact that both the measurement data of the rolling test and the shaft and / or sensor data of the gear cutting machine are specified in relation to rotation, i.e. in relation to the rotation of the respective parts, means that correlations can be found directly. In this way, errors or defects in the gear cutting machine, such as faulty shafts, drives, bearings, etc., can be directly inferred from the deviations measured during the rolling test.
[0009] Specifying the gear cutting machine axis and / or sensor data as data related to the rotation of the part allows for a simplified comparison with measurement data from rolling tests, for example, compared to the purely time-based basis of this data known in the prior art.
[0010] According to one design of the method, it may be provided that the rotation-related axis data is provided as an order spectrum, in particular by FFT. The abbreviation FFT stands for Fast Fourier Transform in a known manner. Since the orders are multiples of the rotation speed of the component, the measured deviations or measurements are plotted as amplitudes over the individual orders.
[0011] According to one design of the method, it may be provided that the rotation-related sensor data is provided as an order spectrum, in particular by FFT. The abbreviation FFT stands for Fast Fourier Transform, in a known manner. Since the orders are multiples of the rotation speed of the component, the measured deviations or measurements are plotted as amplitudes over the individual orders.
[0012] The rotation-related results of the rolling test are provided as an order spectrum, in particular by FFT. The abbreviation FFT stands for Fast Fourier Transform, as is well known. Since the orders are multiples of the rotational speed of the component, the measured deviations or measurements are plotted as amplitudes over the individual orders.
[0013] The orders of the rolling test can be directly compared to the orders of the gear cutting machine shaft data and / or sensor data. For example, if an anomaly occurs in the order spectrum of the rolling test and the order spectrum of the shaft data, e.g., at order 2 or 9, it can be inferred that there is a direct correlation between the deviations in the shaft data and the rolling test. If gear cutting machine components can be specifically assigned to corresponding orders of the shaft data, then calibrating and / or maintaining those components can reduce or eliminate errors in subsequently manufactured gears.
[0014] For example, it may be provided that a first component of the gear cutting machine, such as a bearing, drive, etc., is assigned at least one order of the order spectrum, and a second component of the gear cutting machine, different from the first component, such as a bearing, drive, etc., is assigned at least one further order of the order spectrum, and defects in the first component and / or the second component are detected based on the amplitude of one of the orders.
[0015] During gear machining, components of gear cutting machines are excited to vibrate, particularly in the range of their natural frequencies, for example, by periodically occurring machining forces and / or traverse movements, i.e., controlled machine axis movements and, in particular, accelerations. Vibrations frequently occur at multiples of the tooth meshing frequency, the tool spindle speed, and / or the work spindle speed. According to the approach of the present invention, all recorded vibrations are identified in relation to the rotation of the workpiece or component, allowing a direct comparison with the results of rolling tests.
[0016] It may be provided that the axis data and / or sensor data are already recorded or stored as data related to the part rotation during the recording. Alternatively, it may be provided that the axis data and / or sensor data are recorded or stored, for example, relative to a time reference or tool rotation, and then converted as data related to the part rotation. In particular, the conversion may be automated and computer-assisted. This conversion may be performed after averaging the data.
[0017] According to one design of the method, it may be provided that averaging of the axis data is performed, in particular averaging per part revolution. Alternatively or additionally, it may be provided that averaging of the sensor data is performed, in particular averaging per part revolution.
[0018] The sensor for recording sensor data can be an acceleration sensor, which is assigned to the workpiece spindle of the gear cutting machine, and the rotational position of the workpiece spindle is recorded simultaneously with the recording of the sensor data of the acceleration sensor. The rotational position is the angular position of the workpiece spindle that carries the part during machining. By simultaneously recording the rotational position of the workpiece spindle, the sensor data of the acceleration sensor can be saved as data relating to the rotation of the workpiece spindle. The acceleration sensor measurements can be averaged for each rotation of the workpiece spindle.
[0019] According to one design of the method, it may be provided that the current consumption of a tool spindle, e.g., a grinding spindle, is recorded as axial data. Again, while the current consumption of the tool spindle is being recorded, the rotational position of the workpiece spindle may be simultaneously recorded to record the current consumption flow in relation to one revolution of the workpiece spindle. The current consumption measurements may be averaged for each revolution of the workpiece spindle. In particular, periodic fluctuations in the current consumption of the workpiece spindle may be correlated with deviations measured in a rolling test. [Brief explanation of the drawings]
[0020] The invention will now be explained in more detail with reference to the drawings which illustrate exemplary embodiments, each of which is shown diagrammatically. [Figure 1] Figure 1 shows a gear grinding machine. [Figure 2] FIG. 2 shows a grinding spindle with a toothed part to be ground. [Figure 3] Figure 3 shows the test stand for single flank rolling tests. [Figure 4] Figure 4 shows the results of the rolling test. [Figure 5] Figure 5 shows the test stand for the rolling test of the two tooth flanks. [Figure 6] Figure 6 shows the order spectrum of the rolling test, axial data, and sensor data. [Figure 7]FIG. 7 shows a flow chart of the method according to the present invention. DETAILED DESCRIPTION OF THE INVENTION
[0021] Figure 1 shows a gear grinding machine, and in particular a gear grinding machine 2. The gear grinding machine 2 has a tool spindle 4 for holding and rotating a grinding tool. The gear grinding machine 2 has a workpiece spindle 6 for holding and rotating a toothed part to be ground. The gear grinding machine has a dressing device 8 for dressing the grinding tool.
[0022] The tool spindle 4, also called grinding tool spindle, is assigned an acceleration sensor 14 for recording sensor data.
[0023] The gear grinding machine 2 has numerically controlled machine axes X, Y, Z, A, B, C, C2, B2 for carrying out translational and rotational relative movements to provide the machining movements required during cutting or dressing of the gears. Furthermore, the gear grinding machine 2 has an axis Z1 with a movable quill 12 for clamping a shaft or mandrel.
[0024] FIG. 2 shows a schematic arrangement of a tool spindle 4 holding a dressable grinding worm 14 and a workpiece spindle 6 holding a toothed part 16 to be ground, a gear 17 being ground.
[0025] During the grinding process, sensor data 18 of the acceleration sensor 10 is recorded as a time signal of acceleration a over time t. Furthermore, axial data 22 in the form of a current consumption I of the motor 20 for rotating the workpiece spindle 4 is recorded as a time signal of current consumption I over time t during the grinding process. The diagrammatically shown curves should be understood as merely a proxy for actual measurement data.
[0026] Furthermore, simultaneously with the sensor data 18 and the axial data 22, the angular position of the workpiece spindle 6 is recorded by a rotary encoder 24 during the grinding process as further axial data 26, in particular as the rotation angle φ over time t.
[0027] FIG. 3 shows an example of a schematic construction of a test stand 28 for carrying out a single flank rolling test of each toothed component 16 .
[0028] The test stand 28 has a first drive 30 and a second drive 32. The first drive 30 is configured to drive a first shaft 34, on which the toothed component 16 to be tested is mounted.
[0029] The second drive 32 is used to brake a mating gear 36 mounted on a second shaft 26 that is coupled to the drive 20 .
[0030] The mating gear 36 is an externally toothed spur gear that meshes with the gear of the part 16. By simultaneously driving the toothed part 16 and braking the mating gear 36, the speed and torque can be set during the test run. It will be understood that the speed and torque curves can also be adjusted. The center distance a1 between the shafts 38, 34 is constant.
[0031] The test stand 16 includes a rotary encoder or angle measurement system 40 , a rotational acceleration sensor 42 , and a structure-borne sound sensor 44 .
[0032] 4 shows a schematic example of a plot of the rotational error F (μm) measured over one revolution U of a gear 16, i.e. the result of a rolling test of a single tooth flank of a single toothed component 16. From this, values for the concentricity error Fr', the tooth-tooth amplitude fi' and the maximum rolling deviation Fi', for example of first order, can be determined in known manner.
[0033] Alternatively or additionally, a two flank rolling test can be carried out. A test stand 46 for a two flank rolling test is shown diagrammatically by way of example in Figure 5. To avoid repetition, identical features are hereinafter assigned the same reference symbols.
[0034] The two flank rolling test differs substantially from the single flank rolling test described above with reference to Figure 3 in that the center distance a2 is not constant during the test. The mating gear 36 is mounted on and supported by a shaft 38 on a movable carriage 48. The movable carriage 48 is supported by a spring device 50 on a stationary counter holder 52.
[0035] The spring device 50 urges the mating gear 36 into tooth contact with the gear of the component 16 under test, forcing both the right-hand wave face and the left-hand tooth face of the gear of the component 16 under test into tooth contact on both sides of the tooth contact.
[0036] During the test, i.e. during rolling of the toothed part 16 and the counter gear 36, the counter gear 36 is pressed with a defined force in the direction of the part 16.
[0037] The deviation is recorded by translational displacement of the movable carriage 34, and a displacement sensor 54 and a vibration sensor 56 are assigned to the carriage 48 to record the measurement data. The results of the rolling test of the two tooth flanks are, for example, the rolling concentricity deviation, the rolling deviation of the two tooth flanks, and the rolling jump of the two tooth flanks.
[0038] The top part of Figure 6 shows a schematic example of an order spectrum determined from the rotational errors measured according to Figure 4. Again, it should be noted that these are only schematic representations and not actual measurements. The orders correspond to multiples of the rotational speed of the part during the rolling test.
[0039] The bottom part of Figure 6 shows a schematic example of an order spectrum generated from the axial or sensor data shown in Figure 3. Thus, the y-axis of the example illustration displays both "acceleration" and "current consumption."
[0040] By comparing the dominant orders, errors or deviations of the gear cutting machine can be assigned to measured deviations of the toothed component. For example, it can be recognized that bearing damage or bearing wear in the tool spindle of the gear cutting machine will directly lead to a measurable rotational error of, for example, second order, of the toothed component. The fact that both the rolling test results and the axial and / or measurement data, respectively, are given in relation to the rotation of the component means that correlations between gear deviations and machine deviations can be easily and directly identified.
[0041] Thus, the method according to the invention can be specified to comprise the following method steps:
[0042] (A) A step of machining a gear of a part 16 by a gear cutting machine 2, in which axis data 22, 26 of machine axes 4 and 6 of the gear cutting machine 2 are recorded during gear machining, and sensor data 18 of at least a sensor 10 of the gear cutting machine 2 are recorded during gear machining.
[0043] (B) providing the axis data 22, 26 recorded in association with one rotation of the part 16 as rotation-related axis data 22, 26 and providing the sensor data 18 recorded in association with one rotation of the part 16 as rotation-related sensor data, wherein the rotation-related axis data is provided as an order spectrum using an FFT and the rotation-related sensor data is provided as an order spectrum using an FFT.
[0044] (C) A step of rolling test of the toothed part using a rolling test stand, wherein measurement data of the rolling test is provided as rotation-related measurement data in relation to one rotation of the part during the rolling test, and the rotation-related result of the rolling test is provided by FFT as an order spectrum.
[0045] (D) A step of comparing the rotation-related axis data and rotation-related sensor data with the rotation-related measurement data of the rolling test to determine a correlation between the gear deviation based on the rotation-related measurement data of the rolling test and the machine deviation based on the rotation-related axis data and rotation-related sensor data. [Explanation of symbols]
[0046] 2. Gear cutting machine 4 Tool Spindle 6 Workpiece Spindle 8 Dressing device 10 Acceleration Sensor 12 Quill 14 Search Warm 16 parts 17 Gears 18 Sensor Data 20 Drive unit 22 axis data 24 rotary encoder 26 axis data 28 Test stand for single flank rolling tests 30 Drive unit 30 Drive unit 34 Shaft 36 Mating gear 38 Shaft 40 Angle Measurement System 42 Rotational acceleration sensor 44 Structure-borne sound sensor 46 Test stand for two-flank rolling tests 48 Carriage 50 Spring device 52 Counter holder 54 Displacement Sensor 56 Vibration Sensor
Claims
1. - a step of machining a gear (17) of a component (16) by a gear cutting machine (2), during which axis data (22, 26) such as axis feed, axis acceleration, power consumption of an axis drive of at least one machine axis (4, 6) of the gear cutting machine (2) are recorded and / or sensor data (18) of at least one sensor (10) of the gear cutting machine (2), such as a structure-borne noise sensor, an acceleration sensor, a distance sensor, etc. are recorded during the machining of the gear (17); providing the axis data (22, 26) recorded relative to one revolution of the part (16) as rotation-related axis data and / or providing the sensor data (18) recorded relative to one revolution of the part (16) as rotation-related sensor data; a rolling test of the toothed component (16) by means of a rolling test stand (3, 5), wherein measurement data of said rolling test are provided as rotation-related measurement data in relation to one revolution of said component (16) during said rolling test; comparing the rotation-related axial data (22, 26) and / or the rotation-related sensor data (18) with the rotation-related measurement data of the rolling test to determine a correlation between gear deviations according to the rotation-related measurement data of the rolling test and machine deviations according to the rotation-related axial data and / or the rotation-related sensor data; A method comprising:
2. the rotation-related axis data is provided as an order spectrum, in particular by FFT, and / or the rotation-related sensor data is provided as an order spectrum, in particular by FFT, The method of claim 1.
3. The rotation-related results of the rolling test are provided as an order spectrum, in particular by FFT; The method according to claim 1 or 2.
4. a first component of the gear cutting machine, such as a bearing, drive, etc., is assigned to at least one order of one of the order spectra, and a second component of the gear cutting machine, different from the first component, such as a bearing, drive, etc., is assigned to at least one further order of one of the order spectra, and defects in the first and / or second component are detected based on the amplitude of one of the orders. The method according to claim 2 or 3.
5. the axial data are averaged, in particular per part revolution, and / or the sensor data are averaged, in particular per part revolution, 5. The method according to any one of claims 1 to 4.
6. an acceleration sensor (10) is provided as a sensor (10) for recording sensor data (18), which acceleration sensor is assigned to the tool spindle (4) of the gear cutting machine (2), and the rotational position of the workpiece spindle (6) is recorded in particular simultaneously with the recording of the sensor data of the acceleration sensor; 6. The method according to any one of claims 1 to 5.
7. the current consumption of the tool spindle (4) is recorded as axial data, and the rotational position of the work spindle (6) is recorded, in particular at the same time as the current consumption of the tool spindle (4) is recorded; 7. The method according to any one of claims 1 to 6.