Quantitative test method and device for meshing phase consistency of duplex planetary gears

Abstract

The invention discloses a quantitative test method and device for meshing phase consistency of duplex planetary gears, and belongs to the technical field of precision gear detection. The method realizes high-precision measurement through an error transfer and compensation principle, and comprises the following steps of: firstly, manufacturing a reference conversion device which has the same parameter as a measured gear but is completely consistent with a theoretical phase, and measuring a tiny phase error of the reference conversion device by using a high-precision instrument to serve as a compensation value beta; then, the reference device is placed in a special measuring device, positioning is carried out through a gear tooth groove, the system reading is adjusted to be a beta value through an adjusting scale, and error calibration is completed; and finally, replacing with a duplex planetary gear to be measured, and measuring a reading change value gamma of the scale under the same condition, so that the value is the actual phase center offset of the gear pair, and quantitative evaluation is realized. The matched measuring device comprises a base platform, a central positioning bush, a small / large gear tooth groove positioning piece and a measuring module with a gauge block. According to the invention, a space angle error which is difficult to directly measure is converted into a linear dimension difference which is easy to measure, the industrial problem that the phase consistency of the duplex planetary gear cannot be accurately and quantitatively detected is solved, and the method has the advantages of advanced measurement principle, high precision and simplicity and convenience in operation.

Description

Technical Field

[0001] This invention belongs to the field of precision mechanical measurement and gear testing technology, specifically relating to a quantitative inspection method and special device for the meshing phase consistency (also known as "tooth-to-tooth" phase relationship) of double planetary gears in high-reliability transmission systems such as aero-engines and wind turbine gearboxes. Background Technology

[0002] Double planetary gears are the core components of planetary gear transmission systems. They are typically machined from a single piece by two gears with different numbers of teeth and modules, meshing with the sun gear and the internal ring gear, respectively. The relative circumferential position between the two gears—that is, the meshing phase consistency—has a decisive influence on the load distribution, vibration noise, and fatigue life of the transmission system. Ideally, the center lines of designated teeth (such as the "first tooth" marked during machining) of the two gears in a double planetary gear should completely coincide on the axial projection. However, due to machining errors (such as indexing errors and heat treatment deformation), the actual phase of the two gears will inevitably have a slight deviation. This deviation will cause the meshing impact of each tooth pair to be asynchronous when the planetary gear meshes with the sun gear and the internal ring gear simultaneously, resulting in uneven load distribution, which in turn leads to increased system vibration, increased noise, and a significant reduction in the life of gears and bearings.

[0003] Currently, in industrial production, there is a lack of effective, accurate, and quantitative methods for verifying the phase consistency of double planetary gears. Common practices include:

[0004] 1. Visual inspection or magnifying glass inspection: Observe the end face of the gear under a projector or tool microscope, and judge whether the tooth grooves of the two gears are "aligned" based on experience. The result is subjective, cannot be quantified, and has extremely low accuracy.

[0005] 2. Indirect measurement using a coordinate measuring machine (CMM): This method involves measuring the spatial coordinates of multiple tooth surfaces on two gears separately, fitting their respective centerlines through complex mathematical calculations, and then calculating their included angles. This method requires expensive equipment, has high environmental requirements, low measurement efficiency, and its measurement accuracy is limited by probe radius compensation and fitting algorithms. It also exhibits significant uncertainty for measurements with small angular deviations (often angular increments).

[0006] 3. Functional pairing test: The gears are installed in a simulated transmission system for testing, and the evaluation is indirect by monitoring vibration or strain. This method is a post-production verification and cannot be used for in-process inspection and screening during production, and it is also very costly.

[0007] Therefore, the industry urgently needs a method and specialized tooling that can directly, quickly, quantitatively, and with high precision detect the meshing phase consistency of double planetary gears, so as to achieve effective control of the quality of key components and provide accurate input data for the optimized design of transmission systems. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of existing detection technologies and provide a quantitative inspection method and device for the meshing phase consistency of double planetary gears. This method aims to transform the abstract and difficult-to-measure spatial angular deviation into a linear dimensional deviation that is easily read directly using conventional measuring tools (such as dial indicators) through precise mechanical design and ingenious error propagation principles, thereby achieving high-precision, high-efficiency, and low-cost quantitative detection.

[0009] To achieve the above objectives, this invention proposes an innovative technical solution based on the principle of "reference conversion and error compensation".

[0010] Core Invention Concept: Directly measuring the spatial angle (a minute angle) between the centerlines of two gears is extremely difficult. The key to this invention lies in designing and manufacturing a "reference conversion device." This device itself is a pair of "double-linked incomplete gears" with identical geometric parameters (module, number of teeth, pressure angle) to the measured double planetary gears, and ideally, perfectly aligned in phase. Then, using an instrument with higher precision than the final measuring device (such as a high-precision coordinate measuring machine or laser interferometer), the unavoidable minute manufacturing error inherent in this "reference conversion device" (i.e., the actual phase deviation between the two gears) is measured first, and this error value β is accurately recorded. Next, this reference device is placed in a dedicated "measuring device," and the known error β is "reproduced" using the readings of the gauges on the measuring device, that is, the zero point of the gauges is "intentionally" adjusted to the value of β. The essence of this operation is to "calibrate" or "compensate" for both the manufacturing error of the "reference conversion device" and the systematic error of the "measuring device" itself. Finally, the actual gear under test is used for measurement. The deviation value γ read by the gauge relative to the "new zero point" then purely and directly reflects the phase deviation of the gear under test relative to the "ideal reference". This is a sophisticated concept of "relative measurement" and "error separation".

[0011] In a first aspect, the present invention provides a quantitative verification method for the meshing phase consistency of a double planetary gear.

[0012] The method comprises three logically rigorous stages: a reference calibration stage, an error compensation stage, and a workpiece measurement stage.

[0013] Phase 1: Preparation of the reference calibration and reference conversion device 1. Design and manufacture of the reference conversion device: This device consists of two parts: a pinion shaft and a gear shaft. Only 1-3 "incomplete teeth" are machined on each shaft. The tooth profile parameters (module, pressure angle, addendum coefficient, etc.) of these teeth must be completely consistent with the corresponding gear of the double planetary gear being measured. During machining, the pinion shaft and the gear shaft are separate.

[0014] 2. Establish a high-precision assembly datum: On the pinion shaft, using the center plane of a designated tooth (referred to as "datum tooth S1") as a datum, a high-precision cylindrical positioning shaft segment (e.g., diameter d, cylindricity <0.001mm) is precision machined. Correspondingly, a positioning hole (clearance fit, clearance <0.005mm) is precision machined on the large gear shaft to precisely fit it.

[0015] 3. Precision Assembly and Adjustment: The large gear shaft is fitted onto the positioning section of the small gear shaft through the positioning holes. Using a high-precision adjustment table and optical measuring instruments (such as an autocollimator), with the centerline of the small gear shaft's reference tooth S1 as the absolute reference, the circumferential angle of the large gear shaft is finely adjusted until the centerline of the designated reference tooth S2 on the large gear shaft theoretically coincides perfectly with the centerline of S1 in its axial projection. This adjustment process requires extremely high precision; the final coaxiality / concentricity error must be controlled within the micrometer level (e.g., within 0.005 mm).

[0016] 4. Rigid Connection and Error Measurement: After adjustment, immediately use an interference-fit cylindrical pin or special adhesive to rigidly connect the two shafts, forming a single unit, i.e., the "datum conversion device". Subsequently, use a high-precision measuring instrument (such as a coordinate measuring machine with a high-precision probe) to measure the actual positional deviation of the two reference teeth S1 and S2 in the specified measurement direction, and record the absolute value of this deviation as the calibration compensation value β. The β value represents the slight imperfection of the "ideal datum" in the real world.

[0017] Phase Two: Setting the Error Compensation for the Measurement System (Resetting to Zero) 1. Install the reference device: Install the reference conversion device with its positioning shaft section into the center positioning hole of the special measuring device.

[0018] 2. Circumferential Positioning: Push the pinion positioning element (a block with a single precise tooth groove) on the measuring device so that its tooth groove fully meshes with the pinion reference tooth S1 on the reference conversion device. This operation determines the unique circumferential angular position of the reference conversion device within the measuring device.

[0019] 3. Install the measurement module and establish the measurement chain: Install the detachable measurement module onto the measuring device. This module includes a large gear tooth locating component and a gauge block. Push the measurement module so that the tooth groove of the large gear tooth locating component meshes with the large gear reference tooth S2 on the reference conversion device. At this time, one finely ground working surface of the gauge block will automatically contact the probe of the gauge (such as a dial indicator) fixed on the measuring device and compress a certain distance to generate a preload.

[0020] 4. Zeroing the gauge (actually adjusting to the β value): Observe the gauge reading. Because the error of the reference conversion device itself is β, and the measuring device itself may also have minor systematic errors, the gauge reading is not zero at this time. Key operation: Adjust the gauge dial (or adjust the fine-tuning mechanism of the gauge block) so that the gauge pointer is precisely aligned with the previously measured calibration compensation value β. This means that the "zero point" of the entire measurement system (including the reference component error and the device systematic error) is set at the β value. At this moment, the system considers the current state to be "ideal zero".

[0021] Phase 3: Phase error measurement of the gear under test 1. Changing the workpiece: Carefully remove the measuring module and take off the reference conversion device. Install the double planetary gear to be inspected into the center positioning hole of the measuring device in the same way (through its central journal).

[0022] 2. Repeated positioning: Use a pinion tooth positioning element to mesh with a designated tooth (usually marked "0 tooth") on the pinion of the gear under test to determine its angular position.

[0023] 3. Final Measurement: Reinstall the measuring module, ensuring the large gear tooth positioning component meshes with the corresponding designated tooth on the large gear of the gear under test. The gauge probe then contacts the gauge block again.

[0024] 4. Reading Results: Observe and record the scale reading at this point. Since the "zero point" of the measurement system was set to the "ideal reference state" (corresponding to the β value) in the second stage, the change in the scale reading γ is the actual offset of the two specified tooth centerlines of the gear under test relative to the "ideal reference state". The value of |γ| is the quantitative evaluation index of the meshing phase consistency of the double planetary gear. Whether γ is positive or negative indicates the direction of the offset.

[0025] As a further technical solution of the present invention: In order to evaluate the circumferential uniformity of gear phase error, multiple different tooth pairs (such as every 90 degrees or 120 degrees) can be selected as reference teeth, and the second and third stages can be repeated to obtain a set of measurement values ​​γ1, γ2, γ3... for statistical analysis.

[0026] Secondly, the present invention provides a dedicated quantitative testing device for implementing the above-described method.

[0027] This device is a highly integrated and streamlined specialized inspection tool, mainly consisting of the following parts: Base platform: A heavy-duty cast iron or granite platform providing a stable reference, with internal reinforcing ribs. The upper surface of the platform is precision ground to serve as the mounting reference surface.

[0028] Center positioning mechanism: A high-precision, wear-resistant bushing is press-fitted or inlaid at the center of the platform. Its inner diameter d is in a small clearance fit with the positioning journal of the double planetary gear being measured (usually a section of the journal at either end of the gear's center hole). This bushing provides precise radial positioning for the gear, ensuring the repeatability of the axial position during each installation.

[0029] Pinion positioning module: Fixed to one side of the platform. The core is a small gear positioning component, a slider that slides along a precision linear guide, with a single-toothed positioning block made of hardened steel embedded at its front end. The tooth profile of this tooth is exactly the same as the parameters of the pinion being measured. By pushing the slider with a handle, the tooth can mesh with the designated tooth on the gear, achieving precise circumferential positioning and locking.

[0030] Gauge mounting module: Fixed to the other side of the platform, at a specific angle (usually 90° or parallel, depending on the measurement direction) to the pinion positioning module. It includes a gauge positioning base with mutually perpendicular, finely ground reference surfaces for quick and accurate mounting and clamping of gauges (micrometers or inductive micrometers), ensuring that the gauge probe direction is strictly consistent with the measurement direction.

[0031] Detachable measurement module (core functional module): This is a separate component, including: Measurement substrate: a rigid frame.

[0032] Large gear positioning component: Fixed on the measuring base, it is also a positioning block with a single tooth groove, and its tooth profile is consistent with the parameters of the large gear being measured.

[0033] Gauge block: A standard gauge block in the shape of a cuboid or cylinder, ground to have one working surface with extremely high flatness and roughness. This gauge block is precisely fixed to the measuring base. The key is that the normal direction of the working surface of the gauge block in contact with the gauge must precisely pass through the central symmetry plane of the tooth groove of the large gear tooth locator. This fixed geometric relationship is crucial to ensuring correct measurement direction and linearly transmitting the deviation of the tooth groove center position to the gauge.

[0034] The measuring module can be quickly and repeatedly installed onto the base platform via its guide structure (such as guide posts) or by manual alignment. During installation, the tooth groove of the large gear positioning component meshes with the designated tooth on the gear, while the working surface of the gauge block automatically contacts the probe of the gauge.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Innovative Measurement Principle and High Precision: By employing the principle of "reference conversion and error compensation," spatial angular deviations are cleverly converted into linear dimensional deviations for measurement, avoiding the technical difficulties of directly measuring minute angles. High-precision reference components are used for system calibration, effectively separating and compensating for the system errors of the measuring device itself. This ensures that the final measurement result (γ value) directly and accurately reflects the phase error of the workpiece, achieving micrometer-level measurement accuracy and corresponding arcsecond-level angular resolution.

[0036] 2. Simple operation and high efficiency: The specialized device standardizes and semi-automates the testing process. The operator only needs to complete a few simple actions: "clamping the workpiece → meshing and positioning → installing the module → taking the reading." A single measurement can be completed within 2-3 minutes, making it very suitable for process inspection and batch screening on the production site. Its efficiency is far higher than that of coordinate measuring machine (CMM).

[0037] 3. Quantitative results, objective and reliable: The measurement result γ is a specific value that can be accurately recorded, and clear pass / fail thresholds can be set (such as |γ| ≤ 0.015mm), realizing the objectification and data-driven management of quality judgment, which is convenient for statistical process control (SPC).

[0038] 4. Relatively low cost: Compared with relying on expensive coordinate measuring machines, the special device of this invention has a moderate manufacturing cost and is more adaptable to the environment (temperature, vibration). It can be used in ordinary metrology rooms or workshops, which greatly reduces the testing costs of enterprises.

[0039] 5. Provide direct feedback for process improvement: The accurate γ value can be directly fed back to the gear processing steps (such as hobbing, gear shaping, and gear grinding), help locate the source of error (such as indexing mechanism problems, fixture eccentricity, etc.), guide the optimization of process parameters, and improve the quality of gear manufacturing from the source.

[0040] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the overall process of the quantitative testing method of the present invention.

[0042] Figure 2 This is a three-dimensional structural diagram of an embodiment of the dedicated quantitative testing device of the present invention (the measurement module has been installed).

[0043] Figure 3 This is a structural schematic diagram (sectional view) of the reference conversion device, the core component of this invention.

[0044] The following are the labels in the attached diagram: 1. Base platform; 2. Gauge holder; 3. Large gear tooth positioning component; 4. Positioning frame; 5. Small gear tooth positioning component; 6. Gauge positioning component; 7. Measuring base; 8. Gauge block; 9. Small gear shaft; 10. Large gear shaft; 11. Cylindrical pin. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some embodiments of this invention, but not all embodiments.

[0046] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0047] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention.

[0048] The following is in conjunction with the appendix Figure 1-3 The embodiments of the present invention will be described in detail below.

[0049] Example 1: Implementation steps of the testing method See Figure 1 This embodiment provides a quantitative inspection method for the meshing phase consistency of a double planetary gear. The core of this method lies in utilizing a high-precision reference conversion device to convert the spatial phase error of the gear, which is difficult to measure directly, into a linear dimensional deviation that can be read using conventional gauges. Furthermore, a systematic calibration process eliminates the device's own errors, ultimately achieving an accurate and quantitative evaluation of the phase consistency of the gear under inspection. The specific steps are as follows: Step 1: Preparation and self-error calibration of the reference conversion device First, make such Figure 3 The reference conversion device is shown. This device consists of a pinion shaft 9 and a large gear shaft 10 rigidly connected by a cylindrical pin 11. The pinion shaft 9 has incomplete teeth (denoted as reference teeth S1) machined on it, with the exact same pitch circle parameters as the smaller gear in the double planetary gear set to be tested. The large gear shaft 10 has incomplete teeth (denoted as reference teeth S2) machined on it, with the same pitch circle parameters as the larger gear in the double planetary gear set to be tested. During assembly, the center of reference teeth S1 is used as a reference, and fine adjustments are made to ensure that the center of reference teeth S2 theoretically coincides with it, with a maximum allowable deviation controlled within 0.01 mm. Then, the two shafts are locked together using the cylindrical pin 11, forming a rigid whole with theoretically perfectly synchronized phase.

[0050] Despite the extremely high precision of the machining and assembly, the reference conversion device itself still has minor manufacturing errors. It requires calibration using high-precision instruments (such as a coordinate measuring machine). Figure 3 As shown, a reference plane, precisely parallel to the center plane of the reference tooth S2, is machined on the non-tooth profile rotation surface of the large gear shaft 10. Along the normal direction of this reference plane, the distance L1 from the center of the reference tooth S1 on the pinion shaft 9 to this plane, and the distance L2 from the center of the reference tooth S2 on the large gear shaft 10 to this plane, are measured respectively. The absolute value of the difference between the two is calculated, which yields the tooth phase consistency error of the reference conversion device itself, denoted as the calibration value β. β = |L1 - L2| This β value will be used as the error compensation benchmark in subsequent measurements.

[0051] Step 2: Error compensation of the measuring device (system zeroing) The purpose of this step is to "reproduce" the known error β of the reference conversion device on the measuring device, thereby bringing the overall error of the measuring system (including the reference device) to zero.

[0052] 1. Install the reference conversion device: Figure 3 The reference conversion device shown is mounted on the measuring device via precision shaft segments (diameter d) provided on its pinion shaft 9 and gear shaft 10. Figure 2 The center positioning is achieved by using the corresponding precision cylindrical positioning hole on the base platform 1.

[0053] 2. Circumferential Positioning: Operate the pinion positioning module on the measuring device. Push the pinion tooth positioning component 5 so that its involute internal tooth groove fully meshes with the reference tooth S1 of the pinion shaft 9 on the reference conversion device. Through the constraint of the positioning frame 4, the precise circumferential and angular positioning of the reference conversion device in the measuring device is completed.

[0054] 3. Install the measurement module and establish the measurement chain: Install the measurement module (consisting of the large gear tooth positioning component 3, the measurement base 7, and the gauge block 8) onto the measuring device. Push the module so that the involute internal tooth groove on the large gear tooth positioning component 3 fully meshes with the reference tooth S2 of the large gear shaft 10 on the reference conversion device. During this process, the specific working surface of the gauge block 8 fixed on the measurement base 7 will automatically contact the probe of the gauge (such as a dial indicator) mounted on the gauge holder 2, generating a stable preload. The position of the gauge holder 2 is constrained by the smoothed vertical sidewall of the gauge positioning component 6, ensuring that the direction of the gauge probe is fixed.

[0055] 4. Scale Reading Compensation: Observe the scale reading at this point. Due to the inherent error β of the reference conversion device and the potential for minor systematic errors in the measuring device, the scale pointer is not pointing to the theoretical zero position. Key Operation: Adjust the scale dial (or use other fine-tuning mechanisms) to precisely align the scale pointer reading with the calibration value β measured in step one. This operation means defining the state where "the reference conversion device is installed on the measuring device, and the scale reading is β" as the "ideal zero position" of the entire measuring system. After completion, remove the measuring module and then remove the reference conversion device.

[0056] Step 3: Phase error measurement of the double planetary gear under test This step involves directly measuring the workpiece error on a system that has already undergone error compensation.

[0057] 1. Install the gear to be inspected: Position the double planetary gear to be inspected by its precision-machined journal (diameter d) and install it into the same precision cylindrical hole of the base platform 1.

[0058] 2. Circumferential positioning: Similar to step two, the pinion tooth positioning component 5 is used to mesh with the designated reference tooth (usually the marking tooth) of the pinion on the gear to be inspected to achieve circumferential positioning of the gear to be inspected.

[0059] 3. Final Measurement and Reading: Reinstall the measurement module so that the large gear tooth positioning component 3 meshes with the corresponding reference tooth of the large gear on the gear to be inspected. The gauge block 8 then contacts the measuring instrument probe again.

[0060] 4. Result Acquisition: Directly read the scale reading at this time and record it as γ. Since the "zero point" of the measurement system has been set to the value (β) of the ideal state of the corresponding reference conversion device in step two, the current reading γ is the actual center offset between the two reference teeth of the double planetary gear under test after eliminating system errors. The absolute value of γ is the quantitative evaluation index of the meshing phase consistency of the gear. If the maximum allowable offset according to the process requirements is Δ, then when |γ| ≤ Δ, the gear is qualified; otherwise, it is unqualified.

[0061] Step 4: (Optional) Multi-tooth position measurement and statistical analysis To comprehensively evaluate the phase consistency of gears, multiple tooth pairs (e.g., every 90° or 120°) can be uniformly selected on the gear circumference as measurement references. For each selected tooth pair, steps two (error compensation must be completed on the first measurement, and subsequent measurements share this zero point) and three are repeated to obtain a set of measurement values ​​γ1, γ2, γ3, …. By analyzing this set of data (e.g., calculating the range and standard deviation), the circumferential uniformity of the gear phase error distribution can be assessed, providing a more detailed basis for process improvement.

[0062] Example 2: Structure and Use of the Testing Device See Figure 2 This embodiment provides a dedicated quantitative testing device that complements the above method. This device has a compact structure, streamlined operation, and effectively ensures measurement consistency and efficiency.

[0063] Detailed explanation of the device structure: 1. Base Platform 1: This serves as the mounting foundation for the entire device. It employs a hollow steel cuboid structure with built-in reinforcing ribs, providing sufficient rigidity and stability to minimize the impact of deformation on measurement accuracy. A high-precision cylindrical hole is machined at a critical location on the platform. Its diameter d is determined based on the locating journal dimensions of the double planetary gear under inspection, providing precise radial center positioning for the reference conversion device and the gear under inspection.

[0064] 2. Pinion positioning module: Fixedly mounted on the base platform 1, used for circumferential and angular positioning of the object being measured. This module mainly includes: Positioning bracket 4: Provides installation reference and guidance.

[0065] Pinion gear positioning component 5: A movable part along the positioning frame, its working end is machined with an involute internal tooth groove. The tooth profile parameters of this groove are completely consistent with the pinion gear in the double planetary gear to be inspected. By pushing the pinion gear positioning component 5, its tooth groove meshes with the designated tooth on the gear, thus locking the gear in a unique angular position.

[0066] 3. Measuring Instrument Mounting Module: Used to fix the measuring instrument and ensure consistency of measurement direction. This module includes: Gauge positioning component 6: It is a set of rectangular steel blocks with precision-ground sidewalls, whose smooth vertical sidewalls form the installation reference surface.

[0067] Gauge holder 2: Used to hold gauges (such as dial indicators). Gauge holder 2 is installed close to the vertical reference surface of gauge positioning component 6, thereby ensuring that the axis of the gauge measuring rod is strictly parallel or perpendicular to the preset measurement direction.

[0068] 4. Measurement Module: This is a standalone, quickly detachable functional module responsible for converting the center position of the tooth grooves of the large gear into linear displacement. This module includes: Measurement base 7: The skeleton of the module, ensuring the stability of the relative positions between the components.

[0069] Large gear positioning component 3: fixed on the measuring base 7, its working end is also machined with involute internal gear grooves that are consistent with the parameters of the large gear in the double planetary gear to be inspected.

[0070] Gauge block 8: A precise, smooth-surfaced standard block mounted on the measuring base 7 in a fixed position. The core technical requirement for its installation is that the working surface of gauge block 8, which contacts the measuring probe, must precisely pass through the geometric center symmetry plane of the tooth groove of the large gear tooth positioning component 3. This design ensures that when the tooth groove of the large gear tooth positioning component 3 meshes with the gear teeth, the position of gauge block 8 directly reflects the position of the tooth groove center.

[0071] Device workflow: 1. Preparation: Prepare the reference conversion device ( Figure 3 Insert it into the positioning hole of the base platform 1.

[0072] 2. Calibration: Position the pinion gear locating component 5 by engaging it with the pinion reference tooth S1 of the reference conversion device. Install the measuring module, making the large gear locating component 3 engage with the large gear reference tooth S2 of the device. At this point, the gauge block 8 contacts the gauge probe. Adjust the gauge reading to the known calibration value β to complete the system zeroing. Remove the measuring module and the reference conversion device.

[0073] 3. Inspection: Install the gear to be inspected and position it by meshing the pinion tooth positioning component 5 with its pinion reference tooth. Install the measuring module so that the large gear tooth positioning component 3 meshes with the corresponding tooth of its large gear.

[0074] 4. Reading: Read the reading γ directly from the scale, which is the measurement result.

[0075] By combining the above-mentioned devices and methods in an orderly manner, a rapid, accurate, and quantitative inspection of the meshing phase consistency of double planetary gears is achieved, effectively solving a long-standing detection problem in this field.

[0076] Example 3 See Figure 1-3 This invention provides a quantitative verification method for the meshing phase consistency of a double planetary gear, which includes the following steps: S1: Through a set of reference conversion devices, the measurement of the phase consistency of the teeth of the double gear is converted into the measurement of the phase consistency of the teeth of a set of double incomplete gears in the reference conversion device. S2: The phase consistency of the teeth of the double-linked incomplete gear in the reference conversion device is detected, and the detected value is recorded as β; S3: Combine a set of measuring devices with a reference conversion device. The positioning mechanism in the measuring device contacts the teeth of the double incomplete gear in the reference conversion device to complete the positioning of the conversion device in the measuring device. S4: Make the gauge block in the measuring module of the measuring device come into contact with the gauge and cause the gauge to generate pressure. S5: Adjust the scale dial reading to match the β value; S6: Remove the measurement module from the measurement device and separate the reference conversion device from the measurement device; S7: Combine the double planetary gear to be inspected with the measuring device. The positioning mechanism in the measuring device contacts the gear teeth in the double gear in the reference conversion device to complete the positioning of the double planetary gear to be inspected in the measuring device. S8: Install the measuring module in the measuring device, read the dial gauge jump value, and record it as γ; then the γ value is the center offset of the two teeth in the double-gear, which can be used to quantitatively describe the phase consistency of the teeth of the double planetary gear. S9: Select multiple measurement points as needed, repeat steps S1-S8 to obtain data γ1, γ2, γ3... for subsequent statistical analysis.

[0077] For example, the quantitative verification method for the phase consistency of the teeth of a double planetary gear first detects the phase consistency of the teeth of the double incomplete gear in the reference conversion device, and the detected value is recorded as β; then, the reference conversion device is installed on the base platform 1 through the precision shaft section d, and the reference conversion device is positioned by meshing the small gear tooth positioning component 5 with the reference tooth in the small gear shaft 9 of the reference conversion device; the large gear tooth positioning component 3, the measuring base 7, and the gauge block 8 constitute the measuring module, and the measuring module is positioned by meshing the large gear tooth positioning component 3 with the reference tooth in the large gear shaft 10; the gauge is installed through the gauge positioning component 6. Correctly position the gauge block in the measuring module of the measuring device so that it contacts the gauge and generates pressure. Adjust the gauge dial reading to match the β value, thus achieving error compensation. Remove the gauge and measuring module, and remove the reference conversion device. Install the double planetary gear to be tested using the same method. Adjust the gauge dial reading to match the β value. Install the large gear tooth positioning component 3, the measuring base 7, and the gauge block 8 to form the measuring module. Read the gauge jump value and record it as γ. The γ value is the center offset of the two teeth in the double planetary gear, which can be used to quantitatively describe the phase consistency of the double planetary gear teeth.

[0078] In one possible embodiment, the reference conversion device described in S1, S2, and S3 has the following geometric features: The main structure of the reference conversion device consists of two alloy steel gear shafts. The small gear shaft 9 is equipped with incomplete gear teeth with the same parameters as the gear with the smaller pitch circle in the double planetary gear to be tested (hereinafter referred to as the small gear). The large gear shaft 10 is equipped with incomplete gear teeth with the same parameters as the gear with the larger pitch circle in the double planetary gear to be tested (hereinafter referred to as the large gear).

[0079] In one possible embodiment, a plane (hereinafter referred to as the reference edge) is provided in the non-tooth rotation surface of the large gear shaft 10, which is parallel to the center plane of the gear tooth S2.

[0080] In one possible embodiment, a high-precision cylindrical hole with high dimensional accuracy is provided on the large gear shaft 10 for a small clearance fit with a high-precision shaft section with high dimensional accuracy provided on the small gear shaft 9.

[0081] In one possible embodiment, with the center of the gear tooth S1 on the pinion shaft 9 as a reference, the large gear shaft 10 is assembled onto the pinion shaft 9 through a precision shaft section, ensuring that the center of S2 coincides with the center of S1, with a maximum tolerance set to 0.01, and the pinion shaft 9 and the large gear shaft 10 are rigidly connected using a cylindrical pin 11.

[0082] In one possible embodiment, the detection of the phase consistency of the double-linked incomplete gear teeth in the reference conversion device described in S2 is as follows: detecting the distance between the reference edge and the center of the reference tooth along the normal direction of the reference edge. Let L1 be the distance from the center of the reference tooth of the pinion shaft 9 to the reference edge, and L2 be the distance from the center of the reference tooth of the large gear shaft 10 to the reference edge. Then, the detection value β described in S2 is: β = |L1 - L2|.

[0083] In one possible embodiment, the pinion shaft 9 is provided with two tapered holes, the tapered angles α1 and α2 of which are generally set to 60°; the joint datum runout formed by the pitch circle D1 of the pinion shaft 9 and the pitch circle D2 of the pinion shaft 2 with respect to α1 and α2 is constrained to be within 0.02.

[0084] In one possible embodiment, a shaft segment with high dimensional accuracy is selected from the double planetary gears to be tested, and its diameter is recorded as d. A high-precision shaft segment with a diameter of d is set in the reference conversion device, and its coaxiality with the joint reference formed by α1 and α2 is constrained; in order to reduce the systematic error generated during the installation and disassembly described in S4, S5, S6 and S7.

[0085] Example 4 See appendix Figure 2-3 This invention provides a quantitative testing device for the meshing phase consistency of a double planetary gear, used in conjunction with the aforementioned reference conversion device. It can be used to perform the above-mentioned double planetary gear tooth phase consistency testing method. It includes: a base platform 1, a gauge holder 2, a large gear tooth positioning component 3, a positioning frame 4, a small gear tooth positioning component 5, a gauge positioning component 6, a measuring base 7, and gauge blocks 8, wherein: The base platform 1 is a hollow steel cuboid with built-in connecting ribs. A precision cylindrical hole of size d is provided at a suitable position on the base platform 1 to provide center positioning for the reference conversion device and the double planetary gear to be inspected. The base platform 1 is equipped with a positioning frame 4, a pinion gear positioning component 5, and a gauge positioning component 6. The positioning frame 4 and the pinion gear positioning component 5 constitute a pinion gear positioning module. The pinion gear positioning component 5 is provided with involute internal tooth grooves, which can mesh with the pinion gear to achieve positioning. The gauge positioning component 6 is a set. A rectangular steel block with smooth sidewalls is arranged vertically to provide positional constraints for the gauge frame 2, ensuring that the relative positions of the gauge frame, the reference conversion device, and the double gear to be inspected are fixed. The large gear tooth positioning component 3, the measuring base 7, and the gauge block 8 constitute the measuring module. The large gear tooth positioning component 3 is provided with an involute internal tooth groove. The gauge block 8 and the large gear tooth positioning component 3 are installed on the measuring base 7 in a fixed positional relationship. During installation, it is ensured that the surface of the gauge block 8 in contact with the gauge passes through the geometric center of the tooth groove of the large gear tooth positioning component 3.

[0086] 1. In inspecting the phase consistency of the teeth of a double planetary gear, this application utilizes the geometric characteristics of an incomplete gear to convert the measurement of the overlap of the virtual plane in the rotating body into the measurement of the distance between the real plane and the virtual plane; at the same time, it uses indirect measurement technology to eliminate the systematic error of the reference conversion device itself.

[0087] 2. The method provided in this application requires easy acquisition of geometric parameters, which can improve measurement accuracy and eliminate dependence on high-precision measurement equipment, thereby reducing measurement costs.

[0088] 3. The method provided in this application has particularly significant advantages in the phase consistency test of spur double gear teeth.

[0089] Thus, the objective of this invention has been achieved.

[0090] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A quantitative verification method for the meshing phase consistency of a double planetary gear, characterized in that, This method uses a high-precision reference conversion device to convert the relative phase error of the double gears into a measurable linear dimensional difference. After compensating for this error on the measuring device, it achieves direct and quantitative measurement of the phase consistency of the gears under test. The method includes the following steps: S1: Reference conversion and calibration: A reference conversion device is provided, which includes a pair of incomplete double gear pairs manufactured according to the requirement that the geometric parameters of the double planetary gears being measured are exactly the same as those of the measured double planetary gears and that the theoretical phase is exactly the same; the phase consistency error value of the two gear teeth of the reference conversion device itself is measured and recorded using a high-precision measuring instrument, and is denoted as the calibration compensation value β. S2: Measurement System Error Compensation Setting: Install the reference conversion device on the positioning base of the measuring device; use the gear positioning mechanism of the measuring device to mesh with the double incomplete gear in the reference conversion device for positioning; install the measuring module so that the gauge block in the measuring module contacts the probe of the gauge fixed on the measuring device and generates a preload; adjust the gauge reading so that its pointer reading is accurately aligned with the calibration compensation value β, thereby reducing the system error of the measuring device to zero; S3: Measurement of the error of the gear under test: Remove the measuring module and the reference conversion device; install the actual double planetary gear to be tested on the positioning base of the measuring device in the same way; reinstall the measuring module so that the probe of the gauge is in contact with the gauge block again; at this time, read the change in the reading of the gauge relative to the zero position set in step S2, and record it as the measured value γ; the measured value γ is the actual tooth phase center offset between the two gears of the double planetary gear under test, and its absolute value is used to quantitatively characterize the degree of consistency of the meshing phase.

2. The quantitative testing method according to claim 1, characterized in that, In step S1, the phase consistency error value β of the reference conversion device itself is obtained in the following way: A mechanical reference plane is set on the large gear shaft of the reference conversion device, which is precisely parallel to the center plane of one of the large gear reference teeth; the normal distance L1 from the center of the small gear reference tooth to the mechanical reference plane and the normal distance L2 from the center of the large gear reference tooth to the mechanical reference plane are measured respectively; the absolute value of the difference between the two is calculated, i.e., β=|L1 -L2|.

3. The quantitative testing method according to claim 1 or 2, characterized in that, The method for manufacturing the reference conversion device includes: The pinion shaft and the large gear shaft are machined separately, with only a few incomplete tooth profiles machined on them for positioning. A high-precision positioning shaft section is machined on the pinion shaft, and a positioning hole that precisely matches it is machined on the large gear shaft. Using the center of the specified tooth profile on the pinion shaft as a reference, the large gear shaft is assembled with the positioning shaft section and the positioning hole, and precisely adjusted using optical or coordinate measurement methods to ensure that the center of the specified tooth profile on the large gear shaft coincides with the center of the specified tooth profile on the pinion shaft in the theoretical position. After adjustment, the two shafts are rigidly locked.

4. The quantitative testing method according to claim 3, characterized in that, High-precision tapered center holes are machined at both ends of the pinion shaft to serve as a unified process reference and measurement reference for the entire reference conversion device during machining, assembly, and use.

5. The quantitative testing method according to claim 1, characterized in that, The positioning base of the measuring device is provided with a precision cylindrical positioning hole, the diameter of which is matched with the diameter of the journal selected as the positioning reference on the double planetary gear to be measured; the reference conversion device is provided with a precision shaft segment with the same diameter as d; in steps S2 and S3, the precision shaft segment of the reference conversion device or the journal of the gear to be measured is centered and positioned through the precision cylindrical positioning hole.

6. The quantitative testing method according to claim 1, characterized in that, To obtain more comprehensive phase consistency information, multiple teeth on the double planetary gear that are circumferentially separated by a specific angle are selected as measurement reference teeth. Steps S2 and S3 are repeated to obtain a set of measurement values ​​γ1, γ2, γ3..., which are used to statistically analyze the circumferential distribution of the gear phase.

7. An apparatus for implementing the quantitative testing method according to any one of claims 1-6, characterized in that, include: The measuring base platform provides a rigid mounting reference for the entire device; A central positioning mechanism, disposed on the base platform, is used to provide radial positioning for a reference conversion device or a double planetary gear under test. The central positioning mechanism includes a precision cylindrical hole or an openable precision positioning sleeve. The pinion positioning module is fixedly installed on the base platform and includes a pinion tooth positioning component with an involute internal tooth groove, which is used to mesh with a designated tooth on the smaller gear in the double gear to achieve circumferential and angular positioning of the gear. The scale mounting module is fixedly mounted on the base platform and includes a scale positioning component that provides vertical and horizontal reference planes and a scale installed therein. The detachable measurement module includes: A measurement substrate; A large gear tooth positioning component fixed on the measuring base has an involute internal tooth groove for meshing with the corresponding tooth on the larger gear in a double gear; A gauge block fixed on the measuring base has its working surface in contact with the measuring probe precisely set in a specific direction passing through the geometric center of the tooth groove of the large gear positioning component. When the measuring module is installed in place by meshing with the gear through the large gear tooth positioning component, the gauge block contacts the probe of the gauge, and the reading of the gauge reflects the relative positional deviation of the specified tooth center of the two gears in the measuring direction.

8. The quantitative testing device according to claim 7, characterized in that, Both the small gear positioning component and the large gear positioning component are single tooth grooves or rack-like structures containing a few teeth, and their tooth profile parameters are completely consistent with the corresponding gear parameters of the gear to be tested.

9. The quantitative testing device according to claim 7, characterized in that, The central positioning mechanism is a precision cylindrical bushing fixed inside the base platform. Its inner diameter d is clearance-fitted with the positioning journal of the double planetary gear to be tested, and the clearance is less than 0.01 mm.

10. The quantitative testing device according to claim 7, characterized in that, The measuring instrument is a dial indicator or an inductive micrometer, and its measuring rod axis, the normal of the working surface of the gauge block, and the center direction of the tooth groove of the large gear positioning component are parallel or coplanar.

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