A multi-directional static stiffness integrated measuring device and method for a circular-arc end tooth connecting structure
Patent Information
- Application Number
- CN202611545227.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-10-08
- Publication Date
- 2026-11-03
AI Technical Summary
Existing technologies cannot achieve decoupling and comprehensive measurement of the lateral, axial and torsional stiffness of the arc-end tooth connection structure on the same tooling platform. Local loading is prone to deformation, the equipment cost is high and it is difficult to adapt to different sizes. There is a lack of effective methods to eliminate tooling deformation interference.
A multi-directional static stiffness integrated measuring device with a circular arc end tooth connection structure is adopted. It utilizes a general platform and modular loading components to measure axial, radial and torsional stiffness on the same device. The deformation during the loading process is monitored by displacement sensors to eliminate tooling deformation interference. The modular design realizes multi-directional stiffness measurement.
It enables efficient and accurate measurement of multi-directional stiffness on the same device, reduces experimental costs, simplifies operation, and improves the stability and accuracy of measurement. It can accurately extract the pure local stiffness of the end tooth meshing surface.
Smart Images
Figure CN123028774A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of rotating machinery measurement technology, and in particular to an integrated multi-directional static stiffness measurement device and method for a circular arc end tooth connection structure. Background Technology
[0002] The circular arc end-tooth connection structure, with its superior alignment accuracy, high torque transmission capability, and excellent disassembly and maintainability, has become a core connecting component for modern aero-engine and gas turbine rotors, widely used in connections between compressor shafts and turbine shafts, and between disks. However, the end-tooth structure is physically a typical discontinuous interface, and this discontinuity in material and structure inevitably causes significant local stiffness loss at the contact surface. Aero-engine rotors typically operate at supercritical speeds, and the lateral, axial, and torsional stiffness of the end-tooth connection area directly determines not only the overall bending critical speed and vibration characteristics of the rotor, but also profoundly affects the overall operational stability and safety margin of the engine. Therefore, a precise assessment of the multi-directional stiffness characteristics of the circular arc end-tooth connection structure is essential during the design phase.
[0003] However, existing evaluation techniques have the following shortcomings: (1) Most test devices are for unidirectional stiffness measurement, and it is impossible to achieve decoupling and comprehensive measurement of lateral, axial and torsional stiffness on the same tooling platform; (2) Local loading or asymmetric loading can easily cause local bending or bulging deformation of thin-walled drums, making it impossible to accurately obtain the stiffness of the end tooth meshing surface itself; (3) Existing equipment often contains complex control systems and actuators, which are costly to manufacture and difficult to universally adapt to test pieces of different sizes; (4) There is a lack of effective testing methods to eliminate the elastic deformation of the tooling itself under stress, making it difficult to obtain the pure local stiffness of the end tooth contact surface. Therefore, developing a device and method with a simplified structure, uniform loading and the ability to achieve accurate measurement of multi-directional stiffness has become an urgent need in engineering applications. Summary of the Invention
[0004] The purpose of this invention is to provide an integrated multi-directional static stiffness measurement device and method for arc-end tooth connection structures. Utilizing a universal platform structure and modular loading components, it accurately measures axial stiffness, radial stiffness, and torsional stiffness on the same device. It has the advantages of simplified structure, uniform loading, elimination of tooling deformation interference, and the ability to extract the local stiffness of the connection structure independently.
[0005] To achieve the above objectives, the present invention provides an integrated multi-directional static stiffness measuring device for a circular arc end tooth connection structure, comprising a first support and a load loading and measuring component. A circular arc end tooth connection structure is horizontally arranged on the first support, and a central connecting rod is inserted inside the circular arc end tooth connection structure. The load loading and measurement component includes replaceable axial stiffness testing modules, radial stiffness testing modules, and torsional stiffness testing modules, which are used to apply test loads along the axial, radial, and torsional directions around the axial direction of the arc-shaped end tooth connection structure and detect the load magnitude, respectively. The measured part of the load loading and measurement component is equipped with a displacement sensor to monitor the displacement change of the measured part during the loading process.
[0006] Preferably, the arc-shaped end tooth connection structure includes a left-end tooth test piece and a right-end tooth test piece that mesh with each other; one end of the central connecting rod is fixed to the first support, and the other end is provided with a threaded section, on which a toothed nut is assembled, and the toothed nut is used to apply an axial preload to the arc-shaped end tooth connection structure.
[0007] Preferably, the axial stiffness testing module includes a second support and a sleeve converter; the second support is disposed on the outer side of the tail of the first support, serving as a reaction force support base for axial loading; the sleeve converter is sleeved on the right end of the right-end tooth test piece, and the sleeve converter is rigidly connected to the force measuring ring. An axial force applicator is fixedly installed on the second support. The thrust end of the axial force applicator abuts against the end face of the sleeve converter through a force measuring ring to apply a test load along the axial direction.
[0008] Preferably, the radial stiffness testing module includes a hexagonal block, which is fitted onto the outer cylindrical surface of the right-end tooth test piece via an interference fit with a flat key; a radial force applicator is vertically arranged below the arc-shaped end tooth connection structure, and a corresponding force measuring ring is provided on the thrust end of the radial force applicator. The thrust end of the radial force applicator abuts against the bottom end face of the hexagonal block vertically upward through the corresponding force measuring ring to apply a test load radially.
[0009] Preferably, the torsional stiffness testing module includes a hexagonal block clamping assembly; the hexagonal block clamping assembly is a split structure, with the upper and lower parts clamped and fixed to the outer periphery of the hexagonal block by locking bolts.
[0010] Preferably, the hexagonal block clamping assembly extends horizontally outward to form a cantilever arm, the cantilever arm having a preset effective arm length; the thrust end of the radial force applicator abuts vertically upward against the bottom of the cantilever arm through a corresponding force measuring ring, so as to apply a torsional torque around the axial direction to the arc-shaped end tooth connection structure through the arm conversion.
[0011] Preferably, the left end of the left-end tooth test piece is provided with an external mounting flange, and the left-end tooth test piece is fixed to the first support by the external mounting flange and fasteners; the right end of the left-end tooth test piece is provided with an inner end face protrusion tooth.
[0012] Preferably, the left end of the right-end tooth test piece is provided with an inner end face concave tooth that matches the inner end face convex tooth. The inner end face convex tooth and the inner end face concave tooth mesh with each other to achieve circumferential and radial positioning of the arc end tooth connection structure.
[0013] Preferably, when performing axial stiffness testing, the detection end of the displacement sensor is aligned with the right end face of the right-end tooth test piece, and the measurement direction is set along the axial direction; When performing radial stiffness testing, the detection end of the displacement sensor is aligned with the horizontal end face of the hexagonal block, and the measurement direction is set radially. When performing torsional stiffness testing, the probe end of the displacement sensor is aligned with the upper surface of the cantilever arm, and the measurement direction is set vertically.
[0014] This invention also provides an integrated method for measuring the multi-directional static stiffness of a circular arc end tooth connection structure, comprising the following steps: S1. Installation and Axial Preload Calibration: After meshing the left-end tooth test piece with the right-end tooth test piece, install it on the first support, tighten the toothed nut on the center connecting rod, apply the set axial preload to the arc-shaped end tooth connection structure, adjust the displacement sensor to the corresponding measurement position, and record the initial reference displacement. S2. Axial static stiffness measurement: Remove the toothed nut, assemble the axial stiffness test module, apply the axial calibration load through the axial force applicator, and after the displacement sensor reading recovers to the load state corresponding to the initial reference displacement, continue to apply the axial test load, record the axial displacement increment, and calculate the axial static stiffness by combining the load increment. S3. Radial static stiffness measurement: Reinstall the toothed nut and maintain the axial preload, replace it with the radial stiffness test module, apply the radial test load through the radial force applicator, record the radial displacement increment, and calculate the radial static stiffness by combining the radial load. S4. Torsional static stiffness measurement: A torsional stiffness test module is added to the radial stiffness test module. The loading position of the radial force applicator is adjusted to be directly below the cantilever arm. A vertical thrust is applied through the radial force applicator, which is converted into a torsional moment from the cantilever arm. The vertical displacement increment at the cantilever end is recorded. The torsional static stiffness is calculated by combining the arm length and the load.
[0015] Furthermore, in steps S2, S3, and S4, based on Hooke's Law and geometric relationships, the specific calculation formula for the triaxial static stiffness is as follows: Formula for calculating axial static stiffness: ; In the formula, k a For axial static stiffness, For the applied large axial load, For the initial calibration load, This represents the axial relative displacement increment measured by the displacement sensor during loading.
[0016] Radial static stiffness calculation formula: ; In the formula, k r For radial static stiffness, The lateral load applied to the radial force applicator; The change in radial displacement is measured by the displacement sensor.
[0017] Formula for calculating torsional static stiffness about an axis: ; In the formula, k t To reduce static stiffness, The thrust applied by the radial force applicator, L The effective length of the cantilever lever arm. This represents the vertical displacement increment at the cantilever end.
[0018] Therefore, the present invention employs the above-mentioned integrated multi-directional static stiffness measurement device and method for a circular arc end tooth connection structure, and the technical effects are as follows: High degree of functional integration: By changing different loading modules and fixtures, static stiffness measurements in three different directions (axial, radial, and torsional) can be completed on a single set of tooling, significantly reducing experimental construction costs and tooling space requirements.
[0019] Eliminating local deformation errors: Whether it is radial loading or torsional loading, the force is transmitted as a whole through a ring-shaped force-applying ring or hexagonal block clamp, avoiding the problem of asymmetric local deformation of thin-walled cylinders caused by traditional local loading.
[0020] Convenient and efficient measurement: The unit displacement sensor can cover stiffness measurement in three directions, eliminating the need to deploy multiple sensors in a confined space, which significantly simplifies the experimental operation and improves the stability and consistency of the measurement data.
[0021] It can eliminate tooling deformation interference: By aligning the reference of the axial calibration load, it can effectively eliminate the influence of the elastic deformation of the central tie rod and the support on the measurement results and accurately extract the pure local stiffness of the end tooth meshing surface.
[0022] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of an embodiment of the multi-directional static stiffness integrated measuring device with a circular arc end tooth connection structure according to the present invention. Figure 2 This is a schematic diagram of the axial stiffness loading module of an embodiment of the multi-directional static stiffness integrated measuring device with arc-shaped end tooth connection structure of the present invention. Figure 3 This is a front view schematic diagram of the central connecting rod and the end tooth test piece of an embodiment of the multi-directional static stiffness integrated measuring device for a circular arc end tooth connection structure according to the present invention. Figure 4 This is the invention Figure 3 Schematic diagram of the cross-sectional structure at point AA; Figure 5 This is a schematic diagram of the left end tooth test piece of an embodiment of the multi-directional static stiffness integrated measuring device for a circular arc end tooth connection structure according to the present invention; Figure 6 This is a schematic diagram of the right end tooth test piece of an embodiment of the multi-directional static stiffness integrated measuring device for a circular arc end tooth connection structure according to the present invention; Figure 7 This is a schematic diagram of the axial stiffness measuring device structure of an embodiment of the multi-directional static stiffness integrated measuring device with a circular arc end tooth connection structure according to the present invention. Figure 8 This is a schematic diagram of the radial stiffness measuring device structure of an embodiment of the multi-directional static stiffness integrated measuring device with a circular arc end tooth connection structure according to the present invention. Figure 9 This is a schematic diagram of the torsional stiffness measuring device around the axis according to an embodiment of the multi-directional static stiffness integrated measuring device with arc-shaped end tooth connection structure of the present invention.
[0024] Figure Labels 1. First support; 2. Left end tooth test piece; 21. Inner end face convex tooth; 22. Outer mounting flange; 3. Right end tooth test piece; 31. Inner end face concave tooth; 4. Central connecting rod; 41. Toothed nut; 5. Second support; 6. Sleeve converter; 7. Force measuring ring; 8. Axial force applicator; 9. Hexagonal block; 91. Flat key; 10. Radial force applicator; 11. Hexagonal block clamping assembly; 12. Cantilever arm; 13. Displacement sensor. Detailed Implementation
[0025] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.
[0026] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.
[0027] Example 1 like Figures 1-9 As shown, the present invention provides an integrated multi-directional static stiffness measuring device for a circular arc end tooth connection structure, including a first support 1 and a load loading and measuring component. A circular arc end tooth connection structure is horizontally arranged on the first support 1, and a central connecting rod 4 is inserted inside the circular arc end tooth connection structure.
[0028] The arc-shaped end tooth connection structure includes a left-end tooth test piece 2 and a right-end tooth test piece 3 that mesh with each other; one end of the central connecting rod 4 is fixed on the first support 1, and the other end is provided with a threaded section, on which a toothed nut 41 is assembled. The toothed nut 41 is used to apply axial preload to the arc-shaped end tooth connection structure.
[0029] The load loading and measurement assembly includes replaceable axial stiffness test modules, radial stiffness test modules, and torsional stiffness test modules, which are used to apply test loads along the axial, radial, and torsional directions around the axial direction of the arc-shaped end tooth connection structure and detect the load magnitude, respectively. The load loading and measurement assembly is equipped with a displacement sensor 13 at the test part to monitor the displacement change of the test part during the loading process.
[0030] The axial stiffness testing module includes a second support 5 and a sleeve converter 6; the second support 5 is located on the outer side of the tail of the first support 1, serving as a support base for the reaction force of axial loading; the sleeve converter 6 is sleeved on the right end of the right end tooth test piece 3, and the sleeve converter 6 is rigidly connected to the force measuring ring 7. An axial force applicator 8 is fixedly installed on the second support 5. The thrust end of the axial force applicator 8 abuts against the end face of the sleeve converter 6 through the force measuring ring 7 to apply a test load along the axial direction.
[0031] The radial stiffness testing module includes a hexagonal block 9, which is fitted onto the outer cylindrical surface of the right-end tooth test piece 3 via an interference fit with a flat key 91. A radial force applicator 10 is vertically arranged below the arc-shaped end tooth connection structure. A corresponding force measuring ring 7 is provided at the thrust end of the radial force applicator 10. The thrust end of the radial force applicator 10 abuts against the bottom end face of the hexagonal block 9 vertically upward through the corresponding force measuring ring 7 to apply a test load radially.
[0032] The torsional stiffness testing module includes a hexagonal block clamping assembly 11; the hexagonal block clamping assembly 11 is a split structure, with the upper and lower parts clamped and fixed to the outer periphery of the hexagonal block 9 by locking bolts.
[0033] The hexagonal block clamping assembly 11 extends horizontally outward to form a cantilever arm 12, which has a preset effective arm length. The thrust end of the radial force applicator 10 abuts vertically upward against the bottom of the cantilever arm 12 through the corresponding force measuring ring 7, so as to apply a torsional moment around the axis to the arc end tooth connection structure through the arm conversion.
[0034] The left end of the left tooth test piece 2 is provided with an external mounting flange 22, and the left tooth test piece 2 is fixed to the first support 1 by the external mounting flange 22 and fasteners; the right end of the left tooth test piece 2 is provided with an inner end face protrusion tooth 21.
[0035] The left end of the right-end tooth test piece 3 is provided with an inner end face concave tooth 31 that matches the inner end face convex tooth 21. The inner end face convex tooth 21 and the inner end face concave tooth 31 mesh with each other to achieve circumferential and radial positioning of the arc end tooth connection structure.
[0036] When performing axial stiffness testing, the detection end of displacement sensor 13 is aligned with the right end face of right-end tooth test piece 3, and the measurement direction is set along the axial direction. When performing radial stiffness testing, the detection end of displacement sensor 13 is aligned with the horizontal end face of hexagonal block 9, and the measurement direction is set radially. When performing torsional stiffness testing, the detection end of displacement sensor 13 is aligned with the upper surface of cantilever arm 12, and the measurement direction is set vertically.
[0037] The following embodiments use a circular arc end tooth test piece with an outer radius of 40mm as an example for illustration. The core component material configuration is as follows: the central connecting rod 4 and the right end tooth test piece 3 are both made of GH 4169 high temperature alloy, the left end tooth test piece 2 is made of TC11 titanium alloy, and the toothed nut 41 and the hexagonal block 9 are made of 30Cr alloy structural steel.
[0038] Example 2: Radial (Transverse) Static Stiffness Measurement of Arc-End Tooth Connection Structure This embodiment is used to measure the radial static stiffness of a circular arc end tooth connection structure in the direction perpendicular to the axis. The present invention also provides an integrated method for measuring the multi-directional static stiffness of a circular arc end tooth connection structure, including the following steps: Step 1: Device Installation and Displacement Sensor Zeroing. Engage the inner end face convex teeth 21 and inner end face concave teeth 31 of the left-end toothed test piece 2 and the right-end toothed test piece 3, respectively, and apply the set axial preload through the toothed nut 41 of the central connecting rod 4. Install the radial force applicator 10 and the force measuring ring 7 directly below the hexagonal block 9. Align the probe of the displacement sensor 13 with the lower edge horizontal end face of the hexagonal block 9. Activate the sensor and record the initial displacement before loading. Let the displacement reading at this time be... .
[0039] Step 2: Radial Loading. Activate the radial force applicator 10 located below the device, causing it to apply a radial load vertically upwards to the hexagonal block 9. Based on the feedback from the force measuring ring 7, multi-stage loading is performed; in this embodiment, a radial load is applied up to... =1000N (i.e., 1KN).
[0040] Step 3: Real-time displacement measurement. Under stable loading conditions, the reading of displacement sensor 13 is taken as follows: The calculation yields the result under load. Radial displacement increment under action .
[0041] Step 4: Radial stiffness calculation. Substitute the above data into the radial static stiffness formula: ; The radial static stiffness of the R40 specification arc end tooth connection structure under this working condition is obtained. 1.099×10 7 N / m.
[0042] Example 3: Measurement of Axial Static Stiffness of Arc-End Tooth Connection Structure This embodiment is used to measure the axial static stiffness of the arc-shaped end tooth connection structure along the axial direction.
[0043] Step 1: Record the initial displacement. Tighten the toothed nut 41 at the right end of the center connecting rod 4 using a torque wrench to achieve the initial preload on the arc-shaped tooth structure. At this time, align the probe of the displacement sensor 13 with the right end face of the right-end tooth test piece 3 and record the initial displacement. .
[0044] Step 2: Apply thrust. Remove the toothed nut 41 and install the axial loading module (sleeve converter 6, force measuring ring 7, and axial force applicator 8) on the right side of the device. Activate the axial force applicator 8, pushing the sleeve converter 6 to the left along the horizontal axis. Record the axial force calibration value of the force measuring ring 7 at this time, denoted as . Continue to activate axial force applicator 8 to increase the axial thrust to (i.e., 3) ).
[0045] Step 3: Obtain and calculate the axial deformation. Read the reading of displacement sensor 13 at this time and calculate the load increment. Under the action of the action, the axial displacement increment is .
[0046] Step 4: Axial stiffness calculation. Substitute into the axial static stiffness formula: ; The axial static stiffness of the arc-shaped end tooth connection structure is obtained. for .
[0047] Example 4: Measurement of the torsional static stiffness of the arc-shaped end tooth connection structure around its axis This embodiment is used to measure the torsional stiffness of a circular arc end tooth connection structure about its axis.
[0048] Step 1: Install the torsion fixture. On the outside of the previously installed hexagonal block 9, fit the hexagonal block clamping assembly 11 and rigidly lock it to the hexagonal block 9 using bolts on both the upper and lower halves. The hexagonal block clamping assembly 11 extends horizontally outward to form a length of... (i.e., 0.3 meters) cantilever lever arm 12.
[0049] Step 2: Apply the torque around the axis. Move the radial force applicator 10 and the force measuring ring 7 directly below the end of the cantilever arm 12. Activate the radial force applicator 10 to push the bottom end of the cantilever arm 12 vertically upwards. According to the reading of the force measuring ring 7, when the applied force reaches... At that time, the system generates a pure torsional moment about the axis of the test piece. .
[0050] Step 3: Measure the torsional angular displacement. Read the vertical displacement change from the displacement sensor 13 positioned above the cantilever arm 12. .
[0051] Step 4: Calculate torsional stiffness. Substitute into the torsional static stiffness formula: ; The torsional static stiffness about the axis of the arc-shaped end tooth connection structure is obtained. for .
[0052] It should be noted that the specific loading and displacement values in the above three embodiments are merely specific application examples of the measuring device and method of the present invention. In actual engineering measurements, the above values will vary depending on the specific dimensions, materials, and load conditions of the measured end tooth structure. In this embodiment, both the axial and radial force applicators can be mechanical screw jacks or hydraulic loaders. The force-measuring ring is used to accurately monitor the applied load in real time, ensuring the reliability and traceability of the data.
[0053] Therefore, the present invention adopts the above-mentioned integrated multi-directional static stiffness measurement device and method for arc-end tooth connection structure, which accurately measures axial stiffness, radial stiffness and torsional stiffness on the same device. It has the advantages of simplified structure, uniform loading, elimination of tooling deformation interference, and ability to extract the local stiffness of the connection structure separately.
[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.
Claims
1. A multi-directional static stiffness integrated measuring device for a circular arc end tooth connection structure, characterized in that: It includes a first support and a load loading and measurement component. A circular arc end tooth connection structure is horizontally arranged on the first support, and a central connecting rod is inserted inside the circular arc end tooth connection structure. The load loading and measurement assembly includes an axial stiffness test module, a radial stiffness test module, and a torsional stiffness test module, which are used to apply test loads along the axial, radial, and torsional directions around the axial direction of the arc-shaped end tooth connection structure and detect the load magnitude, respectively. The measured part of the load loading and measurement assembly is equipped with a displacement sensor to monitor the displacement change of the measured part during the loading process.
2. The integrated multi-directional static stiffness measuring device for a circular arc end tooth connection structure according to claim 1, characterized in that: The arc-shaped end tooth connection structure includes a left-end tooth test piece and a right-end tooth test piece that mesh with each other; one end of the central connecting rod is fixed to the first support, and the other end is provided with a threaded section, on which a toothed nut is assembled, and the toothed nut is used to apply axial preload to the arc-shaped end tooth connection structure.
3. The integrated multi-directional static stiffness measuring device for a circular arc end tooth connection structure according to claim 2, characterized in that: The axial stiffness testing module includes a second support and a sleeve converter; the second support is disposed on the outer side of the tail of the first support, serving as a support base for the reaction force of axial loading; the sleeve converter is sleeved on the right end of the right-end tooth test piece, and the sleeve converter is rigidly connected to the force measuring ring. An axial force applicator is fixedly installed on the second support. The thrust end of the axial force applicator abuts against the end face of the sleeve converter through a force measuring ring to apply a test load along the axial direction.
4. The integrated multi-directional static stiffness measuring device for a circular arc end tooth connection structure according to claim 3, characterized in that: The radial stiffness testing module includes a hexagonal block, which is fitted onto the outer cylindrical surface of the right-end tooth test piece via an interference fit with a flat key. A radial force applicator is vertically arranged below the arc-shaped end tooth connection structure. The thrust end of the radial force applicator is equipped with a corresponding force measuring ring. The thrust end of the radial force applicator abuts against the bottom end face of the hexagonal block vertically upward through the corresponding force measuring ring to apply a test load radially.
5. The integrated multi-directional static stiffness measuring device for a circular arc end tooth connection structure according to claim 4, characterized in that: The torsional stiffness testing module includes a hexagonal block clamping assembly; the hexagonal block clamping assembly is a split structure, with the upper and lower parts clamped and fixed to the outer periphery of the hexagonal block by locking bolts.
6. The integrated multi-directional static stiffness measuring device for a circular arc end tooth connection structure according to claim 5, characterized in that: The hexagonal block clamping assembly extends horizontally outward to form a cantilever arm, which has a preset effective arm length. The thrust end of the radial force applicator abuts vertically upward against the bottom of the cantilever arm through a corresponding force measuring ring, so as to apply a torsional torque around the axial direction to the arc-shaped end tooth connection structure through the arm conversion.
7. The integrated multi-directional static stiffness measuring device for a circular arc end tooth connection structure according to claim 6, characterized in that: The left end of the left-end tooth test piece is provided with an external mounting flange, and the left-end tooth test piece is fixed to the first support by the external mounting flange and fasteners; the right end of the left-end tooth test piece is provided with an inner end face protrusion tooth.
8. The integrated multi-directional static stiffness measuring device for a circular arc end tooth connection structure according to claim 7, characterized in that: The left end of the right-end tooth test piece is provided with an inner end face concave tooth that matches the inner end face convex tooth. The inner end face convex tooth and the inner end face concave tooth mesh with each other to achieve circumferential and radial positioning of the arc end tooth connection structure.
9. The integrated multi-directional static stiffness measuring device for a circular arc end tooth connection structure according to claim 8, characterized in that: When performing axial stiffness testing, the probe end of the displacement sensor is aligned with the right end face of the right-end tooth test piece, and the measurement direction is set along the axial direction. When performing radial stiffness testing, the detection end of the displacement sensor is aligned with the horizontal end face of the hexagonal block, and the measurement direction is set radially. When performing torsional stiffness testing, the probe end of the displacement sensor is aligned with the upper surface of the cantilever arm, and the measurement direction is set vertically.
10. A method for integrated measurement of multi-directional static stiffness of a circular arc end tooth connection structure based on the device described in any one of claims 1-9, characterized in that, Includes the following steps: S1. Installation and Axial Preload Calibration: After meshing the left-end tooth test piece with the right-end tooth test piece, install it on the first support, tighten the toothed nut on the center connecting rod, apply the set axial preload to the arc-shaped end tooth connection structure, adjust the displacement sensor to the corresponding measurement position, and record the initial reference displacement. S2. Axial static stiffness measurement: Remove the toothed nut, assemble the axial stiffness test module, apply the axial calibration load through the axial force applicator, and after the displacement sensor reading recovers to the load state corresponding to the initial reference displacement, continue to apply the axial test load, record the axial displacement increment, and calculate the axial static stiffness by combining the load increment. S3. Radial static stiffness measurement: Reinstall the toothed nut and maintain the axial preload, replace it with the radial stiffness test module, apply the radial test load through the radial force applicator, record the radial displacement increment, and calculate the radial static stiffness by combining the radial load. S4. Torsional static stiffness measurement: A torsional stiffness test module is added to the radial stiffness test module. The loading position of the radial force applicator is adjusted to be directly below the cantilever arm. A vertical thrust is applied through the radial force applicator, which is converted into a torsional moment from the cantilever arm. The vertical displacement increment at the cantilever end is recorded. The torsional static stiffness is calculated by combining the arm length and the load.