A high-precision gear single meshing automatic measurement system and method based on multi-domain cooperation

Abstract

The application discloses a high-precision gear single-mesh automatic measurement system and method based on multi-domain cooperation, which comprises a mounting base, a stable rack, a standard gear rotating mechanism, a measured gear rotating mechanism, a double-angle measuring device, a loading mechanism, an ultrasonic contact stiffness in-situ measuring device, a servo pre-tightening closed-loop controller and a data acquisition and processing unit. The two rotating axes are parallel to each other, and the loading mechanism keeps the two gears in single-side tooth surface contact; the data acquisition and processing unit synchronously collects two-way angular displacement signals and determines the transmission error according to the theoretical transmission ratio. The ultrasonic device determines the actual measured stiffness according to the mapping relationship between the pre-calibrated ultrasonic characteristic parameters and the equivalent contact stiffness of the interface, and adjusts the pre-tightening state of the connecting piece when the deviation between the actual measured stiffness and the target stiffness exceeds the threshold. Through structure damping, geometric calibration and interface stiffness closed-loop adjustment, the assembly consistency, measurement repeatability and long-term stability of the measurement system are improved.

Description

Technical Field

[0001] This application relates to the field of precision instruments and gear measurement technology, and in particular to a system and automatic measurement method for automatically measuring the single-sided meshing transmission error of gears through structural stability optimization, rotary shaft system accuracy calibration, and ultrasonic detection and closed-loop adjustment of the contact stiffness of the connection interface. Background Technology

[0002] Precision gear measurement is a crucial technical means to ensure the transmission performance and service reliability of high-end equipment. Single-sided gear meshing measurement involves meshing and rotating a standard gear and the gear under test in a single-sided tooth surface contact state, simultaneously acquiring the angular displacement signals of the two rotating shafts, and calculating the transmission error based on the theoretical transmission ratio. This method can comprehensively reflect the tangential error of the gear and is therefore applied to gear precision inspection and quality evaluation.

[0003] Existing grating-type gear single-sided meshing measuring instruments typically employ high-resolution angle encoders and precision rotary mechanisms to measure the angular deviation between a standard gear and the gear under test. However, in actual measurement processes, environmental vibrations, drive disturbances, and frame structure vibrations can introduce additional angular displacement errors, affecting the repeatability and stability of the measurement results. Furthermore, the standard gear rotary mechanism, the gear under test rotary mechanism, and their supporting frame are usually connected by bolts. The contact stiffness of the connection interface is easily affected by factors such as preload, surface condition, assembly sequence, and vibration relaxation. Traditional assembly methods mainly rely on set tightening torques or manual experience to control the connection state, making it difficult to directly quantify the contact stiffness and its distribution consistency at each connection point. This can potentially lead to changes in the relative posture and dynamic characteristics of the two rotary shaft systems.

[0004] Existing structural optimization, geometric calibration, and software error compensation schemes can reduce some measurement errors to a certain extent, but they usually focus on a single aspect and do not fully consider the coupling relationship between structural load-bearing paths, dynamic stiffness, geometric accuracy of rotating shaft systems, and connection interface states. Especially in applications with high gear precision requirements, such as reducers for new energy vehicles and gearboxes for aerospace, it is still necessary to improve the vibration resistance, assembly consistency, and long-term operational stability of the measurement system. Therefore, there is a need for an automatic measurement system and method for single-sided gear meshing that can collaboratively achieve structural stability optimization, geometric error calibration compensation, and quantitative detection and closed-loop adjustment of connection interface contact stiffness. Summary of the Invention

[0005] This application provides a high-precision automatic measurement system and method for single-sided gear meshing based on multi-domain collaboration. It aims to solve the problems of existing single-sided gear meshing measurement systems being susceptible to structural vibration, geometric errors of rotating shafts and assembly status of key connection interfaces, and the difficulty in quantitatively adjusting the contact stiffness of the connection interface, so as to improve the assembly consistency, measurement repeatability and long-term operational stability of the measurement system.

[0006] According to the first aspect of this application, a high-precision automatic measurement system for single-sided gear meshing based on multi-domain collaboration is provided, including a mounting base, a shape-correlation-coordinated stable frame structure, a standard gear rotation mechanism, a gear under test rotation mechanism, a center distance adjustment mechanism, a loading mechanism, a first angle measuring device, a second angle measuring device, an ultrasonic contact stiffness in-situ measuring device, a precision calibration and compensation module, a servo preload closed-loop controller, a data acquisition and processing unit, and a host computer measurement and control software platform.

[0007] The shape-coordinated stabilization frame structure is mounted on the mounting base; the standard gear rotation mechanism and the gear under test rotation mechanism are arranged opposite to each other on the shape-coordinated stabilization frame structure, with their rotation axes parallel to each other and spaced according to the gear meshing center distance; the center distance adjustment mechanism is used to adjust the meshing center distance between the standard gear and the gear under test; the loading mechanism is used to apply a meshing load to one of the rotation mechanisms, so that the standard gear and the gear under test maintain single-sided tooth surface contact during the measurement process.

[0008] The first angle measuring device is mounted on the standard gear rotation mechanism, and the second angle measuring device is mounted on the gear under test rotation mechanism. Both are used to acquire the angular displacement signals of the standard gear and the gear under test, respectively. The data acquisition and processing unit synchronously acquires the two angular displacement signals using a common sampling clock and calculates the transmission error based on the signed theoretical transmission ratio between the standard gear and the gear under test.

[0009] As a further aspect of this application, the shape-and-dampness co-optimized frame structure includes a topological support beam optimized for stiffness and damping, and phonon crystal damping units disposed inside the topological support beam or at key vibration transmission paths, to improve the static stiffness and dynamic stability of the frame structure and reduce the influence of environmental vibration and system operating vibration on angular displacement measurement.

[0010] As a further aspect of this application, the in-situ ultrasonic contact stiffness measurement device includes a multi-channel ultrasonic probe array, an ultrasonic pulse transmitter / receiver, an ultrasonic signal processing module, and a contact stiffness mapping module. The contact stiffness mapping module stores a pre-calibrated mapping relationship between ultrasonic characteristic parameters and the equivalent contact stiffness of the connection interface; the ultrasonic characteristic parameters include at least one of reflection amplitude, reflection coefficient, phase difference, propagation time, and spectral characteristics.

[0011] As a further embodiment of this application, the servo preload closed-loop controller includes a preload force adjustment actuator, a preload state control module, and a stiffness deviation comparison module. The stiffness deviation comparison module is used to compare the measured contact stiffness of the connection interface with the target contact stiffness; when the relative deviation between the two exceeds a preset threshold, the preload state control module controls the preload force adjustment actuator to adjust the preload state of the corresponding connector.

[0012] in, The measured contact stiffness of the connection interface. For the target contact stiffness, For relative deviation of contact stiffness, A preset allowable deviation threshold is set. The contact stiffness closed-loop adjustment is performed during the assembly stage of the measurement system and / or the calibration stage before the measurement begins. After each adjustment of the pre-tightening state of the connector, the contact stiffness of the connection interface is re-detected after a preset stabilization time until the measured contact stiffness at each detection position meets the preset requirements. Then, the current pre-tightening state is maintained and the system enters the gear measurement stage.

[0013] As a further embodiment of this application, the accuracy calibration and compensation module includes a laser interferometer and a vision alignment camera. The laser interferometer is used to detect the radial rotation error, axial rotation error, and angular positioning error of the standard gear rotation mechanism and the gear rotation mechanism under test. The vision alignment camera is used to detect the parallelism deviation of the two rotation axes, the gear center distance deviation, the tooth width direction position deviation, and the initial meshing position deviation. The data acquisition and processing unit controls the center distance adjustment mechanism to adjust the position based on the detection results, and / or performs error compensation on the single-sided gear meshing measurement results.

[0014] As a further aspect of this application, the data acquisition and processing unit is equipped with an error budgeting and tolerance allocation module. This module, based on the system's maximum allowable measurement error, inversely allocates the manufacturing errors of the components and the assembly pose errors. The maximum error constraint relationship is as follows:

[0015] Where f is the system measurement output error model. Let be the manufacturing error parameter for the i-th component. For the corresponding allowable manufacturing error, Let j be the assembly pose error parameter. For the corresponding allowable assembly error, and Let δmax be the error sensitivity coefficient determined at the nominal state, and let δmax be the maximum allowable measurement error of the system.

[0016] As a further aspect of this application, the host computer measurement and control software platform includes a motion control module, an angular displacement synchronous acquisition module, a measurement result display module, an accuracy calibration and compensation module, and a contact stiffness closed-loop adjustment interface. The contact stiffness closed-loop adjustment interface is used to display the measured contact stiffness, target contact stiffness, and stiffness deviation at each detection position, and is used to set the target contact stiffness and allowable deviation threshold.

[0017] As a further embodiment of this application, the bottom of the mounting base is provided with an air-floating vibration isolation pad, and the air-floating vibration isolation pad, the topological support beam and the phonon crystal vibration reduction unit together constitute a multi-level passive vibration isolation and reduction structure.

[0018] As a further aspect of this application, the outer diameter of the gear being measured is measured in the range of 40mm to 300mm, and the maximum tooth width or maximum axial mounting dimension is 400mm. The above measurement range can be adjusted according to the rotary mechanism, the center distance adjustment mechanism, and the specifications of the fixture.

[0019] According to a second aspect of this application, an automatic measurement method for single-sided gear meshing using the above-described system is provided, comprising: installing a standard gear and a gear under test; adjusting the parallelism of the two rotation axes and the gear meshing center distance; detecting the ultrasonic signal of the key connection interface and determining the equivalent contact stiffness of the interface according to a pre-calibrated mapping relationship; adjusting the preload state of the corresponding connecting parts according to the contact stiffness deviation; ensuring that the standard gear and the gear under test maintain single-sided tooth surface contact and meshing rotation; synchronously acquiring the angular displacement signals of the two rotation axes; calculating the transmission error according to the theoretical transmission ratio and performing error compensation based on the accuracy calibration results; and determining the single-sided gear meshing measurement result based on the compensated transmission error.

[0020] By adopting the above technical solutions, this application utilizes the synergistic effect of topological support structure, local vibration reduction structure, and base vibration isolation structure to reduce the impact of environmental vibration and system operation vibration on angular displacement measurement; it uses dual-path angular displacement synchronous acquisition and theoretical transmission ratio calculation to form a complete gear single-sided meshing transmission error measurement chain; it uses ultrasonic detection to quantify the contact stiffness of key connection interfaces and adjusts the pre-tightening state of the connectors according to stiffness deviation to reduce the difference in connection state between different assembly processes; and it uses laser interferometry, visual alignment, and error compensation to improve the geometric accuracy and relative pose consistency of the rotary shaft system, thereby improving the assembly consistency, measurement repeatability, and long-term operational stability of the measurement system. Attached Figure Description

[0021] The specific embodiments of this application will be further described below with reference to the accompanying drawings. The drawings are used to illustrate the structural relationships and workflow of this application and do not constitute a limitation on the shape, size, or arrangement of the components.

[0022] Figure 1This is a schematic diagram of the overall structure of the automatic measurement system for single-sided gear meshing provided in the embodiments of this application;

[0023] Figure 2 This is a schematic diagram of the shape-coordinated stabilization rack structure provided in the embodiments of this application;

[0024] Figure 3 A schematic diagram of the arrangement of the in-situ ultrasonic contact stiffness measurement device provided in an embodiment of this application;

[0025] Figure 4 This is a schematic diagram illustrating the principle of rotary shaft system accuracy calibration and dual-path angular displacement measurement provided in the embodiments of this application.

[0026] Figure 5 A flowchart for error budgeting and tolerance allocation provided for embodiments of this application;

[0027] Figure 6 A flowchart of closed-loop adjustment of connection interface contact stiffness provided in an embodiment of this application;

[0028] Figure 7 This is a schematic diagram of the host computer measurement and control and automatic measurement method of this application.

[0029] In the diagram: 1. Mounting base; 11. Air-bearing vibration isolation pads; 2. Shape-dependent stabilizing frame structure; 21. Topological support beam; 22. Phononic crystal vibration damping unit; 3. Standard gear rotation mechanism; 31. First angle measuring device; 4. Test gear rotation mechanism; 41. Second angle measuring device; 42. Loading mechanism; 43. Center distance adjustment mechanism; 5. In-situ ultrasonic contact stiffness measuring device; 51. Multi-channel ultrasonic probe array; 52. Ultrasonic pulse transmitter / receiver; 53. Ultrasonic signal processing module; 54. Contact stiffness mapping module; 6. Precision... 61. Calibration and compensation module; 62. Laser interferometer; 7. Vision alignment camera; 8. Laser alignment auxiliary device; 9. Servo preload closed-loop controller; 10. Preload adjustment actuator; 11. Preload state control module; 12. Stiffness deviation comparison module; 13. Data acquisition and processing unit; 14. Error budget and tolerance allocation module; 15. Synchronous acquisition module; 16. Transmission error calculation and compensation module; 17. Upper computer measurement and control software platform; 18. Motion control module; 19. Measurement data display module; 10. Stiffness closed-loop adjustment interface. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. The described embodiments are only some embodiments of this application, and not all embodiments. Other implementation methods obtained by those skilled in the art based on the disclosure of this application without creative effort are all within the protection scope of this application.

[0031] In the description of this application, unless otherwise expressly specified and limited, the terms "connection," "installation," "setup," etc., shall be interpreted broadly and may refer to fixed connections, detachable connections, or integral connections, as well as mechanical or electrical connections. The term "and / or" indicates any one or more combinations of the listed related objects.

[0032] I. System Overall Structure

[0033] like Figure 1 As shown, the automatic gear single-sided meshing measurement system of this embodiment includes a mounting base 1, a shape-and-structure stabilizing frame structure 2, a standard gear rotation mechanism 3, a gear under test rotation mechanism 4, an ultrasonic contact stiffness in-situ measurement device 5, a precision calibration and compensation module 6, a laser alignment auxiliary device 7, a servo pre-tightening closed-loop controller 8, a data acquisition and processing unit 9, and a host computer measurement and control software platform 10. The gear under test rotation mechanism 4 is also equipped with a loading mechanism 42 and a center distance adjustment mechanism 43.

[0034] Mounting base 1 serves as the support platform for the entire system, and the form-coordinated stabilizing frame structure 2 is fixedly mounted on mounting base 1. The standard gear rotation mechanism 3 and the gear under test rotation mechanism 4 are positioned opposite each other on the form-coordinated stabilizing frame structure 2. The first rotation axis of the standard gear rotation mechanism 3 and the second rotation axis of the gear under test rotation mechanism 4 are parallel to each other, and the distance between the two rotation axes is set according to the pitch circle dimensions of the standard gear and the gear under test. The center distance adjustment mechanism 43 can move along the line connecting the two rotation axes to adjust the gear meshing center distance.

[0035] The loading mechanism 42 is connected to the rotating mechanism 4 of the gear under test and is used to apply a braking torque or meshing load opposite to the driving direction of the standard gear, so that the standard gear and the gear under test always maintain contact on the same tooth surface during the measurement process. The loading mechanism 42 can be a torque motor, a magnetic powder brake, a servo motor, or an elastic loading assembly.

[0036] II. Shape-based stabilizing frame and vibration isolation / damping structure

[0037] like Figure 2 As shown, the shape-dependent stabilizing frame structure 2 includes a topological support beam 21 and a phonon crystal damping unit 22. The topological support beam 21 is optimized based on at least one of the following: frame mass, static displacement of key measuring points, low-order natural frequency, and dynamic flexibility, and its material distribution is determined by constraints such as installation space, manufacturing process, and structural strength. The phonon crystal damping unit 22 is located at the main vibration transmission path from the rotary mechanism to the mounting base 1, and is used to attenuate structural vibrations within a predetermined frequency band.

[0038] In an optional embodiment, the phonon crystal vibration damping unit 22 is a local resonant structure formed by the periodic arrangement of mass blocks and elastic layers, and its geometric dimensions and material parameters are determined according to the main disturbance frequency of the system. An air-bearing vibration isolation pad 11 is provided at the bottom of the mounting base 1 to isolate foundation vibration. The aforementioned air-bearing vibration isolation pad 11, topological support beam 21, and phonon crystal vibration damping unit 22 are all passive vibration isolation or damping components, together constituting a multi-stage passive vibration isolation and damping structure.

[0039] III. Dual-path angular displacement measurement and transmission error calculation

[0040] A first angle measuring device 31 is installed on the standard gear rotation mechanism 3, and a second angle measuring device 41 is installed on the gear rotation mechanism 4 under test. The first angle measuring device 31 and the second angle measuring device 41 can be circular grating encoders, photoelectric angle encoders, or other sensors capable of measuring rotation angles. Both angle measuring devices are connected to the synchronous acquisition module 92 and are triggered by a common sampling clock to reduce phase errors caused by asynchronous sampling.

[0041] During the measurement process, the standard gear acts as the driving gear, driving the measured gear to mesh and rotate. The synchronous acquisition module 92 obtains the angular displacement of the standard gear. and the angular displacement of the gear being measured The transmission error calculation and compensation module 93 determines the angular transmission error according to the following formula:

[0042] in, This is the signed theoretical angular transmission ratio determined based on the number of teeth of the standard gear and the gear under test; for external gear pairs, The symbol is used to characterize the opposite directions of the two gears. The transmission error calculation and compensation module 93 calculates the total tangential deviation, the total tangential deviation of one tooth, and the spectral characteristics based on TE(t) within one or more complete meshing cycles.

[0043] IV. Ultrasonic Calibration and Measurement of Contact Stiffness at Connection Interfaces

[0044] like Figure 3 As shown, the ultrasonic contact stiffness in-situ measuring device 5 is positioned at the critical connection interfaces of the shape-coordinated stabilization frame structure 2. These critical connection interfaces include the mating surface between the frame and the rotating mechanism flange, the mating surface between the spindle box and the support base, and other bolted connection interfaces that significantly affect the relative orientation of the two rotating shafts. A multi-channel ultrasonic probe array 51 is positioned near the connection interfaces or acoustically coupled to the interface under test through preset detection holes to acquire ultrasonic echo signals at each detection location.

[0045] The mapping relationship in the contact stiffness mapping module 54 is pre-established through calibration tests. The calibration specimens use the same or similar materials, surface treatments, roughness, contact area, and connector specifications as the actual connection interfaces. Under multiple pre-tightened conditions, ultrasonic echo signals are acquired using an ultrasonic pulse transmitter / receiver 52, and the incremental normal contact stiffness of the corresponding connection interface is measured using an independent force-displacement testing device. The equivalent contact stiffness of the connection interface can be defined as the ratio of the load increment to the interface normal deformation increment:

[0046]

[0047] Where ΔF is the increment of the normal load acting on the connection interface, and Δd is the corresponding increment of the interface normal deformation. The ultrasonic signal processing module 53 extracts the reflection amplitude, reflection coefficient, phase difference, propagation time, or spectral features from the echo signal, and establishes a mapping relationship K=g(P) between the ultrasonic feature parameter vector P and the equivalent contact stiffness K using lookup tables, piecewise fitting, regression models, or machine learning models. Therefore, during actual assembly, the measured contact stiffness of the connection interface can be determined based on the ultrasonic feature parameters, without limiting the protection range to a single analytical formula.

[0048] V. Rotary shaft system calibration and initial meshing alignment

[0049] like Figure 4 As shown, the accuracy calibration and compensation module 6 includes a laser interferometer 61 and a vision alignment camera 62. The laser interferometer 61 is used to detect the radial rotation error, axial rotation error, angular positioning error, or motion straightness error of the standard gear rotation mechanism 3 and the gear rotation mechanism under test 4; the vision alignment camera 62 is used to acquire the gear end face, tooth profile edge, or reference marks set on the shaft system to determine the parallelism deviation of the two rotation axes, the gear center distance deviation, the tooth width direction misalignment, and the initial meshing phase deviation.

[0050] The data acquisition and processing unit 9 generates center distance adjustment commands and alignment prompts based on the calibration results, and controls the center distance adjustment mechanism 43 to adjust the position when necessary. For systematic errors that cannot be completely eliminated by mechanical adjustment, the transmission error calculation and compensation module 93 corrects the measurement results based on a pre-established error compensation model.

[0051] VI. Error Budgeting and Tolerance Allocation

[0052] Please see Figure 5 The data acquisition and processing unit 9 is equipped with an error budget and tolerance allocation module 91. This module establishes the system measurement output error f and the component manufacturing error parameters. Assembly posture error parameters The functional relationship between them is determined, and the sensitivity coefficients of each error source are determined at the nominal state through analytical calculation, finite element analysis, kinematic simulation or single-factor perturbation test.

[0053] When the tolerance allocation objective is to ensure that the maximum measurement error under the worst-case scenario does not exceed the set limit, the following formula is used as a constraint:

[0054] The error budgeting and tolerance allocation module 91 can generate component tolerance tables and assembly allowable deviation tables by combining manufacturing costs, assembly feasibility, and the weights of key error sources, provided that the above constraints are met. For error sources that are independent of each other and can be regarded as random variables, the combined standard uncertainty can also be calculated in the form of root mean square, but the input quantities should be uniformly expressed as standard uncertainty, rather than the unconverted tolerance half-width.

[0055] VII. Closed-loop adjustment of contact stiffness at the connection interface

[0056] like Figure 6 As shown, the servo preload closed-loop controller 8 is connected to the ultrasonic contact stiffness in-situ measuring device 5. The servo preload closed-loop controller 8 includes a preload force adjustment actuator 81, a preload state control module 82, and a stiffness deviation comparison module 83. The preload force adjustment actuator 81 can be an electric servo wrench, a servo nut drive assembly, or other actuators capable of changing the preload state of the connector.

[0057] Contact stiffness closed-loop adjustment is performed during the system assembly stage and / or the calibration stage before measurement begins. First, each connector is initially pre-tightened according to a preset initial torque or preload; then, the multi-channel ultrasonic probe array 51 acquires ultrasonic signals at each detection location, and the contact stiffness mapping module 54 determines the measured contact stiffness Km; the stiffness deviation comparison module 83 compares Km with the target contact stiffness Kt. When… When K is greater than the allowable deviation threshold ε, the preload control module 82 controls the preload force adjusting actuator 81 to adjust the corresponding connecting parts according to the deviation direction and magnitude.

[0058] After each adjustment, wait for the preset stabilization time, then acquire the ultrasonic signal again and recalculate the contact stiffness. Repeat the above detection, comparison, and adjustment process until all key detection locations meet the requirements. After adjustment, maintain the pre-tightened state of each connecting part and stop the operation of the pre-tightening force adjusting actuator 81 before proceeding to the gear measurement stage to avoid interference from the adjustment action on the angular displacement acquisition. The allowable deviation threshold ε is determined based on the calibration uncertainty, assembly repeatability, and measurement system stability requirements; in one example, ε can be set to 0.5% to 1%, but this range does not constitute a limitation of this application.

[0059] VIII. Upper Computer Measurement and Control and Automatic Measurement Methods

[0060] Please see Figure 7 The host computer measurement and control software platform 10 is communicatively connected to the data acquisition and processing unit 9, the standard gear rotary mechanism 3, the loading mechanism 42, and the servo pre-tightening closed-loop controller 8. The motion control module 101 is used to set the drive speed, loading torque, sampling time, and measurement cycle; the measurement data display module 102 is used to display the two angular displacement signals, transmission error curve, tangential comprehensive deviation result, and spectrum analysis result; the stiffness closed-loop adjustment interface 103 is used to display the contact stiffness, target value, relative deviation, and adjustment status of each detection position.

[0061] When using the above system to perform automatic measurement of single-sided gear meshing, the following steps can be followed:

[0062] 1. Install the standard gear and the gear under test on the standard gear rotation mechanism 3 and the gear under test rotation mechanism 4 respectively, and set the initial center distance according to the gear specifications.

[0063] 2. Use the precision calibration and compensation module 6 to detect the geometric errors and relative positional deviations of the two rotary axes, and adjust the parallelism of the rotary axes, the center distance of the gears, and the position in the tooth width direction.

[0064] 3. Acquire ultrasonic signals at key connection interfaces during the assembly stage or calibration stage before measurement begins. Determine the measured contact stiffness based on the pre-calibrated mapping relationship, and cyclically adjust the pre-tightening state of the connectors according to the stiffness deviation until the preset threshold is met.

[0065] 4. Apply meshing load through loading mechanism 42 to keep the standard gear and the gear under test in contact on one side of the tooth surface and drive the two gears to mesh and rotate.

[0066] 5. The angular displacement signals output by the first angle measuring device 31 and the second angle measuring device 41 are synchronously acquired using a common sampling clock.

[0067] 6. Calculate the transmission error TE(t) based on the signed theoretical transmission ratio, and perform error compensation in conjunction with the calibration results of the rotary shaft system.

[0068] 7. Calculate the total tangential deviation, the total tangential deviation of one tooth, and other set evaluation parameters based on the compensated transmission error, and display and save the measurement results.

[0069] IX. Prototype Verification Example

[0070] In a set of prototype verifications used to illustrate the implementation effect of this application, the outer diameter measurement range of the gear under test was set to 40 mm to 300 mm, and the measurable module range was set to 1 mm to 8 mm; both the first angle measuring device 31 and the second angle measuring device 41 adopted high-resolution circular grating encoders, and the data acquisition system used a common sampling clock for synchronous acquisition. The test environment temperature was maintained at 20 ℃ ± 0.5 ℃. The above parameters are only for embodiment parameters and do not constitute a limitation on the scope of protection of this application.

[0071] In the structural vibration comparison test, the angular displacement noise before and after setting the phonon crystal damping unit 22 was compared; in the connection interface assembly comparison test, the stiffness distribution dispersion after manual constant torque assembly and ultrasonic contact stiffness closed-loop adjustment was compared; in the measurement repeatability test, the same gear was repeatedly measured multiple times under the same installation and measurement conditions, and the repeatability was evaluated by the standard deviation, range or measurement capability index of the measurement results; in the long-term stability test, the same gear was repeatedly measured within a specified time interval, and the drift of the measurement results was recorded.

[0072] In an example test, a gear with a module of 2.5 mm and 30 teeth was selected. The standard gear speed was set to 60 r / min, the applied torque was set to 10 N·m, and the single acquisition time was set to 10 s. The same gear was measured 10 times repeatedly. The average total tangential deviation was 12.3 μm with a standard deviation of 0.28 μm, the average tangential deviation of a single tooth was 3.2 μm with a standard deviation of 0.11 μm, and the peak-to-peak transmission error was 0.8′. These results should be interpreted in conjunction with the tolerance zone used, the measurement capability evaluation method, the reference standard, and the instrument uncertainty.

[0073] In an example long-term stability test, the same gear was measured under the same conditions for 10 consecutive days, and the maximum drift of the total tangential deviation was 0.5 μm. This result indicates that under the test conditions, the synergistic application of structural vibration reduction, geometric calibration, and interface stiffness adjustment is beneficial to improving the repeatability and time stability of the measurement results.

[0074] In summary, this application, through the parallel arrangement of dual rotating shafts, simultaneous acquisition of dual-path angular displacement, single-sided tooth surface loading, structural stability optimization, geometric calibration of the rotating shaft system, and ultrasonic closed-loop adjustment of the contact stiffness of the connection interface, forms a collaborative technical solution from structural design and assembly state control to gear transmission error measurement and compensation. This is beneficial to improving the assembly consistency, measurement repeatability, and long-term operational stability of the gear single-sided meshing measurement system.

[0075] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Those skilled in the art can make modifications or equivalent substitutions to the above embodiments without departing from the technical concept of this application, and all modifications or substitutions should fall within the protection scope defined by the claims of this application.

Claims

1. A high-precision gear single-mesh automatic measurement system and method based on multi-domain collaboration, characterized in that, include: Mounting base (1); A shape-coordinated stable frame structure (2) is mounted on the mounting base (1); The standard gear rotation mechanism (3) and the gear rotation mechanism under test (4) are arranged opposite to each other on the shape-coordinated stabilizing frame structure (2), and the first rotation axis of the standard gear rotation mechanism (3) and the second rotation axis of the gear rotation mechanism under test (4) are parallel to each other; The center distance adjustment mechanism (43) is connected to the standard gear rotation mechanism (3) and / or the gear under test rotation mechanism (4) and is used to adjust the meshing center distance between the standard gear and the gear under test. The first angle measuring device (31) and the second angle measuring device (41) are used to acquire the angular displacement signals of the standard gear rotary mechanism (3) and the gear rotary mechanism under test (4), respectively. The loading mechanism (42) is connected to the standard gear rotation mechanism (3) or the gear under test rotation mechanism (4) to apply a meshing load so that the standard gear and the gear under test maintain single-sided tooth surface contact. An ultrasonic contact stiffness in-situ measuring device (5) is set at the connection interface between the standard gear rotation mechanism (3) and / or the gear rotation mechanism under test (4) and the shape-coordinated stabilizing frame structure (2), including a multi-channel ultrasonic probe array (51), an ultrasonic pulse transmitter / receiver (52), an ultrasonic signal processing module (53) and a contact stiffness mapping module (54). The servo preload closed-loop controller (8) includes a preload force adjustment actuator (81), a preload state control module (82), and a stiffness deviation comparison module (83). The data acquisition and processing unit (9) is connected to the first angle measuring device (31), the second angle measuring device (41), the ultrasonic contact stiffness in-situ measuring device (5), and the servo pre-tightening closed-loop controller (8), respectively. The data acquisition and processing unit (9) is configured to: determine the measured contact stiffness of the connection interface based on the ultrasonic detection signal obtained by the ultrasonic contact stiffness in-situ measuring device (5); when the deviation between the measured contact stiffness and the target contact stiffness exceeds a preset threshold, control the preload adjustment actuator (81) to adjust the preload state of the connector; and simultaneously acquire the angular displacement signals of the first angle measuring device (31) and the second angle measuring device (41), and determine the transmission error based on the theoretical transmission ratio between the standard gear and the gear under test.

2. The automatic gear single-sided meshing measurement system as described in claim 1, characterized in that, The first angle measuring device (31) and the second angle measuring device (41) are angle encoders installed on the corresponding rotary mechanisms and connected to the same synchronous acquisition module (92); the synchronous acquisition module (92) synchronously acquires the first angular displacement signal based on a common sampling clock. Second angular displacement signal The transmission error calculation and compensation module (93) is based on: Determine the transmission error, where, The signed theoretical angular transmission ratio between the standard gear and the gear under test is given.

3. The automatic gear single-sided meshing measurement system as described in claim 1, characterized in that, The center distance adjustment mechanism (43) can move along the line connecting the first rotation axis and the second rotation axis; the loading mechanism (42) is one of a torque motor, magnetic powder brake, servo motor or elastic loading component, used to apply a braking torque or meshing load opposite to the driving direction to the standard gear rotation mechanism (3) or the gear rotation mechanism under test (4).

4. The automatic gear single-sided meshing measurement system as described in claim 1, characterized in that, It also includes a precision calibration and compensation module (6), which includes a laser interferometer (61) and a vision alignment camera (62); the laser interferometer (61) is used to acquire the radial rotation error, axial rotation error and / or angular positioning error of the two rotary mechanisms, and the vision alignment camera (62) is used to acquire the parallelism deviation of the two rotary axes, the gear center distance deviation, the tooth width direction position deviation and / or the initial meshing position deviation; the data acquisition and processing unit (9) generates the adjustment command of the center distance adjustment mechanism (43) and / or compensates for the transmission error based on the detection results of the precision calibration and compensation module (6).

5. The automatic measurement system for single-sided gear meshing as described in claim 1, characterized in that, The ultrasonic signal processing module (53) is used to extract at least one ultrasonic feature parameter from the ultrasonic echo signal acquired by the multi-channel ultrasonic probe array (51), including reflection amplitude, reflection coefficient, phase difference, propagation time and spectral characteristics; the contact stiffness mapping module (54) stores the mapping relationship established by the ultrasonic test results of the calibrated specimen under multiple pre-tightening states and the interface equivalent contact stiffness obtained by independent force-displacement test, and uses a lookup table, piecewise fitting function, regression model or machine learning model to represent the mapping relationship.

6. The automatic measurement system for single-sided gear meshing as described in claim 1, characterized in that, The data acquisition and processing unit (9) determines the average contact stiffness and contact stiffness distribution uniformity of the connection interface based on the measured contact stiffness corresponding to multiple detection positions; the stiffness deviation comparison module (83) generates a pre-tightening state adjustment command based on the average contact stiffness, the contact stiffness distribution uniformity and the corresponding target value.

7. The automatic measurement system for single-sided gear meshing as described in claim 1, characterized in that, The servo pre-tightening closed-loop controller (8) is configured to perform the following loop during the system assembly phase and / or the calibration phase before measurement begins: acquiring ultrasonic detection signals at the connection interface and determining the measured contact stiffness. Calculate the relative stiffness deviation: exist Greater than the preset allowable deviation threshold Adjust the pre-tightening state of the corresponding connector in a timely manner, and reacquire the ultrasonic detection signal after a preset stabilization time, until... ,in, The target contact stiffness.

8. The automatic measurement system for single-sided gear meshing as described in claim 1, characterized in that, The shape-coordinated stable frame structure (2) includes a topological support beam (21) optimized for stiffness-damping coordination and a phonon crystal damping unit (22) disposed inside the topological support beam (21) and / or at key vibration transmission paths; the bottom of the mounting base (1) is provided with an air-floating vibration isolation pad (11), and the air-floating vibration isolation pad (11), the topological support beam (21) and the phonon crystal damping unit (22) together constitute a multi-level passive vibration isolation and damping structure.

9. The automatic measurement system for single-sided gear meshing as described in claim 1, characterized in that, The data acquisition and processing unit (9) is equipped with an error budget and tolerance allocation module (91), which establishes the system measurement output error f and the component manufacturing error parameters. and assembly pose error parameters The error propagation relationship between them, and the allowable manufacturing error is allocated according to the following formula. and allowable assembly error : in, and Let be the error sensitivity coefficient determined at the nominal state. This represents the maximum allowable measurement error of the system.

10. An automatic measurement method for single-sided gear meshing implemented using the system described in any one of claims 1 to 9, characterized in that, include: Install the standard gear and the gear under test, and adjust the parallelism of the two rotation axes and the center distance of gear meshing; Acquire the ultrasonic detection signal of the key connection interface, and determine the measured contact stiffness based on the mapping relationship between the pre-calibrated ultrasonic characteristic parameters and the equivalent contact stiffness of the interface. The measured contact stiffness is compared with the target contact stiffness. When the deviation between the two exceeds a preset threshold, the pre-tightening state of the corresponding connector is adjusted. The ultrasonic testing and pre-tightening state adjustment are repeated until the measured contact stiffness meets the preset requirements. A meshing load is applied by a loading mechanism to keep the standard gear and the gear under test in contact on one side of the tooth surface and mesh and rotate. The angular displacement signals of the standard gear rotary mechanism and the gear rotary mechanism under test are synchronously acquired based on a common sampling clock, and the transmission error is determined according to the theoretical transmission ratio. The transmission error is compensated based on the accuracy calibration results of the rotary shaft system, and the single-sided meshing measurement results of the gear are determined based on the compensated transmission error.

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