A machine tool spindle comprehensive performance testing device and testing method

Abstract

The application discloses a machine tool spindle comprehensive performance testing device and testing method, which comprises: a ground iron, a three-dimensional section axis-determining multi-sensor adjusting module, an axial loading unit, a radial loading unit, a loading arm, a spindle fixing module, a static stiffness module, a working stiffness module, a detection module and a workbench. The device can detect multiple performances of the machine tool spindle through different tool handle modules and loading units, reduces the cumbersome work caused by replacing the test bench, and greatly improves the testing efficiency. The test projects that can be completed by the test bench include thermal elongation testing, thermal deviation testing, axial static stiffness testing, radial static stiffness testing, axial working stiffness testing and radial working stiffness testing of the machine tool spindle.

Description

Technical Field

[0001] This invention relates to the field of equipment testing, and in particular to a comprehensive performance testing device and method for machine tool spindles. Background Technology

[0002] The spindle is one of the key functional components in a CNC machine tool, and its performance directly affects the machining accuracy and quality of the machine tool. For example, the spindle's thermal expansion and thermal offset during long-term operation, as well as its working stiffness and static stiffness, are crucial to the machining accuracy of the machine tool. However, the spindle performance testing devices demonstrated in existing technologies (CN200910191497.9, CN201710068020.6, CN202110636288.1) still have four drawbacks: First, when testing spindle stiffness, the loading device directly loads the test bar, which results in the measurement of the elastic deformation of the test bar, directly affecting the spindle performance test results; Second, when performing axial stiffness testing, because the loading device overlaps with the central axis of the machine tool spindle, the sensor can only be placed on one side of the central axis of the machine tool spindle, which leads to deviations in axial displacement measurement; Third, the testing device has poor versatility and cannot meet the performance testing needs of different models and specifications of machine tool spindles; Fourth, the testing items that the above-mentioned testing devices can perform are relatively limited, and different test benches need to be changed when performing different tests, which is cumbersome and inefficient. To overcome the above defects, this invention provides a comprehensive performance testing device and method for machine tool spindles. Summary of the Invention

[0003] The purpose of this invention is to overcome the above-mentioned defects and provide a comprehensive performance testing device and method for machine tool spindles.

[0004] A comprehensive performance testing device for machine tool spindles includes: a ground level 1, a three-dimensional section axis-multi-sensor adjustment module, an axial loading unit, a radial loading unit 10, a loading arm 12, a spindle fixing module, a static stiffness module 22, a working stiffness module 11, a detection module, and a worktable 20.

[0005] The three-dimensional section axis-multi-sensor adjustment module, the main shaft fixing module, and the radial loading unit 10 are positioned and connected to the ground level 1; the axial loading unit is positioned and connected to the main shaft fixing module; the detection module is positioned and connected to the three-dimensional section axis-multi-sensor adjustment module; the static stiffness module 22 or the working stiffness module 11 is positioned and connected to the axial loading unit or the radial loading unit 10 through the loading arm 12.

[0006] The aforementioned three-dimensional sectional fixed-axis multi-sensor adjustment module includes: a slide module base 2, a slide module 3, a three-axis moving platform heightening frame 4, a three-axis moving platform 5, a sensor bracket fixing seat 6, a sensor bracket 7, and a standard length bar 8;

[0007] The slide module base 2 is fixedly connected to the ground iron 1 by bolts. The slide module 3 is fixedly connected to the slide module base 2 by bolts. The three-axis moving platform extension frame 4 is fixedly connected to the moving platform on the slide module 3 by bolts. The three-axis moving platform 5 is fixed to the three-axis moving platform extension frame 4 by bolts. The sensor bracket fixing seat 6 is fixedly connected to the three-axis moving platform 5 by bolts. The sensor bracket 7 is an integrated bracket, which is fixedly connected to the sensor bracket fixing seat 6 by bolts. The sensor hole on the sensor bracket 7 is provided with an annular protrusion. The standard length bar 8 and the laser displacement sensor 21 have corresponding annular grooves. By twisting the bolts to reduce the inner diameter of the sensor hole, the standard length bar 8 or the laser displacement sensor 21 can be fixed on the sensor bracket 7.

[0008] The detection module includes: a laser displacement sensor 21, a double-ball detection rod 9, a collet nut 11-1, and a collet 11-2;

[0009] The collet 11-2 is installed inside the working stiffness tool holder 11-7 or the static stiffness tool holder 22-2, and clamps the double ball detection rod 9 by cooperating with the collet nut 11-1.

[0010] The axial loading unit includes: a single-bar ball joint 13, an S-shaped tension sensor 15, and an axial loading electric cylinder 17;

[0011] The single-bar ball joint 13 is screwed into the threaded through hole at one end of the loading arm 12 and fixed. The S-type tension sensor 15 has internal threaded holes at both ends and is fixedly connected to the axial loading electric cylinder 17 and the single-bar ball joint 13, respectively.

[0012] The radial loading unit 10 includes: a radial loading unit base 10-1, a radial loading unit fixing seat 10-2, a radial loading electric cylinder 10-3, a pressure sensor 10-4, and a radial loading head 10-5;

[0013] The radial loading unit mounting base 10-2 has an upper fork-shaped structure, and its lower part is fixedly connected to the radial loading unit base 10-1 by bolts; the radial loading electric cylinder 10-3 is fixedly connected to the radial loading unit base 10-1 by bolts; the pressure sensor 10-4 is fixedly connected to the radial loading electric cylinder 10-3 by bolts; the radial loading head 10-5 has a mushroom-shaped structure, with a hemispherical upper part and a stud at the lower part, which can be screwed into the pressure sensor 10-4 for fixation.

[0014] The static stiffness module 22 includes: a static stiffness loading block 22-1 and a static stiffness tool holder 22-2;

[0015] The static stiffness loading block 22-1 has a fork-shaped structure with a through hole in the middle. Square notches are provided on both sides of the static stiffness loading block 22-1 for installing the loading arm 12. The static stiffness loading block 22-1 is fixedly connected to the static stiffness tool holder 22-2 by bolts. The collet 11-2 is installed inside the static stiffness tool holder 22-2 and clamps the double ball detection rod 9 by cooperating with the collet nut 11-1.

[0016] The working stiffness module 11 includes: a bearing pressure ring 11-3, a locking nut 11-4, a working stiffness loading block 11-5, an angular contact bearing 11-6, and a working stiffness tool holder 11-7;

[0017] The working stiffness loading block 11-5 has a fork-shaped structure with a through hole in the middle for installing the angular contact bearing 11-6. The working stiffness loading block 11-5 has square notches on both sides for installing the loading arm 12. The angular contact bearing 11-6 is installed on the working stiffness tool holder 11-7. The outermost cylindrical part of the working stiffness tool holder 11-7 is threaded for installing the locking nut 11-4 and the collet nut 11-1 to tighten the angular contact bearing 11-6. The collet 11-2 is installed inside the working stiffness tool holder 11-7 and clamps the double ball detection rod 9 by cooperating with the collet nut 11-1.

[0018] The spindle fixing module includes: a U-shaped quick-release bracket 14, a spindle test bracket 18, and a spindle test bracket base 19;

[0019] The spindle test bracket base 19 is fixedly connected to the ground iron 1 by bolts. The spindle test bracket 18 is a U-shaped structure with a U-shaped hole in the middle. Its lower part is fixedly connected to the spindle test bracket 18 by bolts. The axial loading electric cylinder 17 is distributed on the middle extension structure on both sides of the spindle test bracket 18 and is fixedly connected by bolts. The U-shaped quick-release bracket 14 has a through hole in the middle for installing the tested electric spindle. The combination of the two is fixedly connected to the spindle test bracket 18 by bolts.

[0020] The three-dimensional section fixed axis-multi-sensor adjustment method is as follows: install the standard length bar 8 onto the sensor bracket 7 and fix it, move the slide module 3 to control the axial distance between the standard length bar 8 and the double ball detection bar 9 within 2~5mm, and fix the position of the slide module 3; adjust the three-axis moving platform 5 so that the standard length bar 8 located in the axial and radial directions is in complete contact with the spherical surface of the double ball detection bar 9, then lock the three-axis moving platform 5, remove the standard length bar 8, and install the laser displacement sensor 21 in place.

[0021] A method for testing the comprehensive performance of a machine tool spindle, using the aforementioned comprehensive performance testing device for a machine tool spindle, includes: a method for testing the thermal elongation and thermal offset of the machine tool spindle, a method for testing the axial and radial static stiffness of the machine tool spindle, a method for testing the axial working stiffness of the machine tool spindle, and / or a method for testing the radial working stiffness of the machine tool spindle.

[0022] The method for testing the thermal elongation and thermal offset of the machine tool spindle comprises the following steps:

[0023] a. Install the test spindle: Install the test spindle 16 onto the U-shaped quick-release bracket 14 and fix it with bolts, and then install the assembly onto the spindle test bracket 18 and fix it with bolts;

[0024] b. Install the test device: Install the double ball test bar 9 onto the static stiffness tool holder 22-2, and then install the tool holder onto the spindle under test 16;

[0025] c. Sensor installation and debugging: Install the laser displacement sensor 21 according to the three-dimensional section axis-multi-sensor adjustment method;

[0026] d. Start the test and collect data: Start the spindle and gradually increase it to the maximum speed. Collect data from the axial and radial laser displacement sensors 21 and the temperature data of the spindle under test 16 through the worktable 20.

[0027] e. Data processing: Based on the data collected by the workbench 20, plot the temperature-axial displacement and temperature-radial displacement curves of the tested spindle and give the thermal elongation and thermal offset of the tested spindle.

[0028] The aforementioned method for testing the axial and radial static stiffness of the machine tool spindle, such as Figure 10 As shown:

[0029] a. Install the test spindle: Install the test spindle 16 onto the U-shaped quick-release bracket 14 and fix it with bolts, and then install the assembly onto the spindle test bracket 18 and fix it with bolts;

[0030] b. Install the test device: Fix the static stiffness loading block 22-1 to the static stiffness tool holder 22-2 with bolts, then install the double ball test bar 9 onto the tool holder, and finally install the static stiffness module 22 onto the spindle under test 16.

[0031] c. Sensor installation and debugging: Install the laser displacement sensor 21 according to the three-dimensional section axis-multi-sensor adjustment method;

[0032] d. Axial static stiffness test: Extend the axial loading electric cylinder 17 and connect the S-type tension sensor 15, single-bar ball joint 13, loading arm 12 and static stiffness module 22 in sequence; set the axial force value and start loading. After the force value stabilizes, collect the data from the laser displacement sensor 21 and S-type tension sensor 15 located in the axial direction through the worktable 20, and calculate the axial static stiffness of the tested spindle.

[0033] e. Radial static stiffness test: Extend the radial loading electric cylinder 10-3 so that the radial loading head 10-5 is in complete contact with the bottom of the static stiffness loading block 22-1; set the radial force value and start loading. After the force value stabilizes, collect the data from the laser displacement sensor 21 and pressure sensor 10-4 located in the radial direction through the worktable 20, and calculate the radial stiffness of the tested spindle.

[0034] The aforementioned method for testing the axial working stiffness of the machine tool spindle, such as Figure 11 As shown:

[0035] a. Install the test spindle: Install the test spindle 16 onto the U-shaped quick-release bracket 14 and fix it with bolts, and then install the assembly onto the spindle test bracket 18 and fix it with bolts;

[0036] b. Install the testing device: Install the double ball test bar 9 onto the working stiffness tool holder 11-7, and then install the working stiffness module 11 onto the spindle under test 16;

[0037] c. Sensor debugging and installation: Install the laser displacement sensor 21 according to the three-dimensional section axis-multi-sensor adjustment method;

[0038] d. Adjustment of axial loading device: Extend the axial loading electric cylinder 17 and connect it in sequence to the S-type tension sensor 15, single-bar ball joint 13, loading arm 12 and working stiffness module 11;

[0039] e. Apply axial load and collect data: Set the axial loading force according to the rotational speed of the spindle under test, start with the minimum load, and gradually increase to the maximum load. Collect data from the laser displacement sensor 21 and S-type tension sensor 15 located in the axial direction through the worktable 20.

[0040] f. Calculate axial working stiffness: Calculate the axial working stiffness of the test spindle at the corresponding speed based on the data collected by the worktable 20.

[0041] The aforementioned method for testing the radial working stiffness of the machine tool spindle, such as... Figure 11 As shown:

[0042] a. Install the test spindle: Install the test spindle 16 onto the U-shaped quick-release bracket 14 and fix it with bolts, and then install the assembly onto the spindle test bracket 18 and fix it with bolts;

[0043] b. Install the testing device: Install the double ball test bar 9 onto the working stiffness tool holder 11-7, and then install the working stiffness module 11 onto the spindle under test 16;

[0044] c. Sensor debugging and installation: Install the laser displacement sensor 21 according to the three-dimensional section axis-multi-sensor adjustment method;

[0045] d. Radial loading device adjustment: Extend the radial loading electric cylinder 10-3 so that the radial loading head 10-5 is in full contact with the bottom of the working stiffness loading block 22-1;

[0046] e. Apply radial load and collect data: Set the radial loading force according to the rotational speed of the spindle under test, start with the minimum load, and gradually increase to the maximum load. Collect data from the laser displacement sensor 21 and the pressure sensor 10-4 located in the radial direction through the worktable 20.

[0047] f. Calculate radial working stiffness: Calculate the radial working stiffness of the tested spindle at the corresponding speed based on the data collected by the worktable 20.

[0048] Advantages of this invention:

[0049] This invention proposes a comprehensive performance testing device for machine tool spindles. This device, through different tool holder modules and loading units, can test multiple performance parameters of the machine tool spindle, reducing the cumbersome work associated with changing test benches and greatly improving testing efficiency. The test bench can perform tests including thermal elongation testing, thermal offset testing, axial static stiffness testing, radial static stiffness testing, axial working stiffness testing, and radial working stiffness testing of the machine tool spindle.

[0050] This invention proposes a spindle fixing device for testing the performance of machine tool spindles. The device consists of a U-shaped quick-release bracket and a spindle testing bracket. The U-shaped quick-release bracket can be customized according to the spindle model, while the spindle testing bracket has a T-shaped structure. This design combines the spindle fixing bracket and the axial loading unit fixing bracket into one, making the overall structure of the test bench extremely compact. It also ensures that the axial loading force is parallel to the spindle axis, thus guaranteeing the accuracy of the test.

[0051] This invention proposes a static stiffness module, which consists of a modified tool holder and a static stiffness loading block. The static stiffness loading block has a fork-shaped structure with square notches on both sides. By connecting different loading units, this module can be used for axial and radial static stiffness testing of machine tool spindles.

[0052] This invention proposes a working stiffness module, which mainly consists of a working stiffness loading block, an angular contact bearing assembly, and a modified tool holder. The working stiffness loading block has a fork-shaped structure with a through hole in the middle for installing the angular contact bearing assembly. By connecting different loading units, this module can be used to test the axial and radial working stiffness of the machine tool spindle in the working state.

[0053] This invention proposes a radial loading unit device, which mainly consists of an electric cylinder, a radial loading unit fixing seat, and a radial loading head. The radial loading unit fixing seat has an upper fork-shaped structure to limit the rotation of the loading block. The radial loading head, through cooperation with the loading block, can achieve accurate application of radial load.

[0054] This invention proposes a three-dimensional section fixed-axis multi-sensor adjustment method. This method uses a three-axis moving platform and a standard length bar to determine the installation position of the laser displacement sensor, so that the laser beams of all laser displacement sensors can hit the highest point of the spherical surface of the detection bar, thereby minimizing the accuracy deviation caused by sensor installation and improving the test accuracy.

[0055] This invention proposes a test method for thermal elongation and thermal offset of machine tool spindle. The method first uses the proposed three-dimensional section axis-multi-sensor adjustment method to precisely adjust the sensor, and then uses a double ball test bar to test the thermal elongation and thermal offset of the spindle during no-load operation.

[0056] This invention proposes a method for testing the axial and radial static stiffness of a spindle. The method uses a static stiffness module to clamp a double-ball detection bar, and utilizes the proposed three-dimensional sectional axis-multi-sensor adjustment method to precisely adjust the sensors to obtain accurate axial and radial displacement data of the spindle. Axial and radial loading is performed using a loading unit module to test the static stiffness of the spindle and provide the axial and radial static stiffness values ​​of the spindle.

[0057] This invention proposes a method for testing the axial working stiffness of a spindle. The method uses a working stiffness module to clamp a double-ball detection bar, and utilizes the proposed three-dimensional sectional axis-multi-sensor adjustment method to precisely adjust the sensors to obtain accurate axial and radial displacement data of the spindle. The method then uses a loading unit to apply load to test the working stiffness of the spindle and provides the axial and radial working stiffness values ​​of the spindle. Attached Figure Description

[0058] Figure 1 Three-dimensional diagram of spindle working stiffness test (standard length bar adjustment);

[0059] Figure 2 Three-dimensional diagram of spindle working stiffness test (laser displacement sensor installed);

[0060] Figure 3 Three-dimensional plot of main shaft static stiffness test;

[0061] Figure 4 Three-dimensional diagram of spindle thermal elongation and thermal offset test;

[0062] Figure 5 A 3D diagram of the radial loading unit module;

[0063] Figure 6 This is an exploded view of the working stiffness module;

[0064] Figure 7 This is an exploded view of the static stiffness module;

[0065] Figure 8 Flowchart of the multi-faceted fixed-axis sensor adjustment method;

[0066] Figure 9 Flowchart of spindle thermal elongation and thermal offset test;

[0067] Figure 10 Flowchart for spindle axial and radial static stiffness testing;

[0068] Figure 11 This is a flowchart of the spindle axial and radial working stiffness test.

[0069] The labels in the attached diagram are:

[0070] 1-Ground level, 2-Slide table module base, 3-Slide table module, 4-Three-axis moving platform extension frame, 5-Three-axis moving platform, 6-Sensor bracket fixing seat, 7-Sensor bracket, 8-Standard length bar, 9-Double ball detection bar, 10-Radial loading unit, 11-Working stiffness module, 12-Loading arm, 13-Single bar ball joint, 14-U-shaped quick-release bracket, 15-S-type tension sensor, 16-Test spindle, 17-Axial loading electric cylinder, 18-Spindle test bracket, 19-Spindle test bracket base, 20-Worktable, 21-Laser displacement sensor, 22-Static stiffness module;

[0071] 10-1-Radial loading unit base, 10-2-Radial loading unit fixing seat, 10-3-Radial loading electric cylinder, 10-4-Pressure sensor, 10-5-Radial loading head;

[0072] 11-1-Collet nut, 11-2-Collet, 11-3-Bearing pressure ring, 11-4-Locking nut, 11-5-Working stiffness loading block, 11-6-Angular contact bearing, 11-7-Working stiffness tool holder;

[0073] 22-1-Static stiffness loading block, 22-2-Static stiffness tool holder. Detailed Implementation

[0074] Example 1: A comprehensive performance testing device for machine tool spindles

[0075] A comprehensive performance testing device for machine tool spindles includes: a ground level 1, a three-dimensional section axis-multi-sensor adjustment module, an axial loading unit, a radial loading unit 10, a loading arm 12, a spindle fixing module, a static stiffness module 22, a working stiffness module 11, a detection module, and a worktable 20.

[0076] The aforementioned three-dimensional sectional fixed-axis multi-sensor adjustment module includes: a slide module base 2, a slide module 3, a three-axis moving platform heightening frame 4, a three-axis moving platform 5, a sensor bracket fixing seat 6, a sensor bracket 7, and a standard length bar 8;

[0077] The aforementioned three-dimensional sectional fixed-axis multi-sensor adjustment module includes: a slide module base 2, a slide module 3, a three-axis moving platform heightening frame 4, a three-axis moving platform 5, a sensor bracket fixing seat 6, a sensor bracket 7, and a standard length bar 8;

[0078] The detection module includes: a laser displacement sensor 21, a double-ball detection rod 9, a collet nut 11-1, and a collet 11-2;

[0079] The axial loading unit includes: a single-bar ball joint 13, an S-shaped tension sensor 15, and an axial loading electric cylinder 17;

[0080] The radial loading unit 10 includes: a radial loading unit base 10-1, a radial loading unit fixing seat 10-2, a radial loading electric cylinder 10-3, a pressure sensor 10-4, and a radial loading head 10-5;

[0081] The static stiffness module 22 includes: a static stiffness loading block 22-1 and a static stiffness tool holder 22-2;

[0082] The working stiffness module 11 includes: a bearing pressure ring 11-3, a locking nut 11-4, a working stiffness loading block 11-5, an angular contact bearing 11-6, and a working stiffness tool holder 11-7;

[0083] The spindle fixing module includes: a U-shaped quick-release bracket 14, a spindle test bracket 18, and a spindle test bracket base 19;

[0084] The floor iron 1 is fixedly connected to the horizontal ground through expansion bolts. The base 2 of the sliding table module is fixedly connected to the floor iron 1 through bolts. The sliding table module 3 is fixedly connected to the base 2 of the sliding table module through bolts. The heightening frame 4 of the three-axis moving platform is fixedly connected to the moving platform on the sliding table module 3 through bolts. The three-axis moving platform 5 is fixed to the heightening frame 4 of the three-axis moving platform through bolts. The fixing seat 6 of the sensor bracket is fixedly connected to the three-axis moving platform 5 through bolts. The sensor bracket 7 is an integral bracket, which is fixedly connected to the fixing seat 6 of the sensor bracket through bolts. There are annular protrusions in the sensor holes on the sensor bracket 7, and there are corresponding annular grooves on the standard length bar 8 and the laser displacement sensor 21. By turning the bolt to reduce the inner diameter of the sensor hole, the standard length bar 8 or the laser sensor 21 can be fixed on the sensor bracket 7, as Figure 1 、 2 shown; The base 19 of the spindle test bracket is fixedly connected to the floor iron 1 through bolts. The spindle test bracket 18 is a T-shaped structure with a U-shaped hole in the middle. Its lower part is fixedly connected to the spindle test bracket 19 through bolts. The axial loading electric cylinder 17 is distributed on the middle extension structures on both sides of the spindle test bracket 18 and is fixedly connected through bolts. As Figure 1 shown; The tested spindle 16 is internally provided with a temperature sensor; There is a through hole in the middle of the U-shaped quick-release bracket 14 for installing the tested spindle 16. The combination of the two is fixedly connected to the spindle test bracket 18 through bolts; One end of the loading arm 12 has a square notch and can be fixedly connected to the working stiffness loading block 11-5 and the static stiffness loading block 22-1 through bolts respectively. The other end is provided with a threaded through hole, and the single-rod ball joint 13 can be screwed in and fixed, as Figure 1 、 3 shown; The S-type tension sensor 15 is provided with internal threaded holes at both ends and is fixedly connected to the axial loading electric cylinder 17 and the single-rod ball joint 13 respectively. The working stiffness module 11 and the static stiffness module 22 can be fixedly connected to the tested spindle 16 through the conventional tool holder fixing method; The double-ball detection rod 9 can be installed on the working stiffness module 11 and the static stiffness module 22 through the conventional tool clamping method and fixed with the collet nut 11-1 and the collet 11-2; The radial loading unit 10 is fixedly connected to the floor iron 1 through bolts.

[0085] The radial loading unit 10 described above is as Figure 5As shown, the radial loading unit fixing seat 10-2 has an upper fork-shaped structure, which is used to limit the rotation of the working stiffness and static stiffness modules 11 and 22. Its lower part is fixedly connected to the radial loading unit base 10-1 by bolts. The radial loading electric cylinder 10-3 is fixedly connected to the radial loading unit base 10-1 by bolts. The pressure sensor 10-4 is fixedly connected to the radial loading electric cylinder 10-3 by bolts. The radial loading head 10-5 has a mushroom-shaped structure. Its upper part is hemispherical. By cooperating with the working stiffness loading block 11-5 and the static stiffness loading block 22-1, it can realize the accurate positioning of the loading point. Its lower part is a stud, which can be screwed into the pressure sensor 10-4 for fixation.

[0086] The working stiffness module is as follows Figure 6 As shown, the working stiffness loading block 11-5 has a fork-shaped structure with a through hole in the middle for mounting the angular contact bearing 11-6. Its lower fork arm can cooperate with the radial loading unit fixing seat 10-2 to limit its own rotation. The working stiffness loading block 11-5 has square notches on both sides for mounting the loading arm 12. The angular contact bearing 11-6 is mounted on the working stiffness tool holder 11-7. The outermost cylindrical part of the working stiffness tool holder 11-7 is threaded for mounting the locking nut 11-4 and the collet nut 11-1 that clamp the angular contact bearing 11-6. The collet 11-2 is installed inside the working stiffness tool holder 11-7 and clamps the double ball detection rod 9 by cooperating with the collet nut 11-1.

[0087] The static stiffness module is as follows Figure 7 As shown, the static stiffness loading block 22-1 has a fork-shaped structure with a through hole in the middle. Its lower fork arm can cooperate with the radial loading unit fixing seat 10-2 to limit its own rotation. The static stiffness loading block 22-1 has square notches on both sides for installing the loading arm 12. The static stiffness loading block 22-1 is fixedly connected to the static stiffness tool holder 22-2 by bolts. The collet 11-2 is installed inside the static stiffness tool holder 22-2 and clamps the double ball detection rod 9 by cooperating with the collet nut 11-1.

[0088] The three-dimensional section fixed axis-multi-sensor adjustment method is as follows: install the standard length bar 8 onto the sensor bracket 7 and fix it, move the slide module 3 to control the axial distance between the standard length bar 8 and the double ball detection bar 9 within 2-5mm, and fix the position of the slide module 3; adjust the three-axis moving platform 5 so that the standard length bar 8 located in the axial and radial directions is in complete contact with the spherical surface of the double ball detection bar 9, then lock the three-axis moving platform 5, remove the standard length bar 8, and install the laser displacement sensor 21 in place.

[0089] Example 2: A method for testing the comprehensive performance of a machine tool spindle

[0090] The test spindle 16 is mounted onto the spindle test bracket 18 via a U-shaped quick-release bracket 14 and secured with bolts. Subsequently, according to different test items, the static stiffness tool holder 22-2, the static stiffness module 22, and the working stiffness tool holder 11-7 and the working stiffness module 11 are mounted onto the test spindle 16 for the corresponding tests.

[0091] Example 3: Stereoscopic Section Axis-Based Multi-Sensor Adjustment Method

[0092] Three-dimensional section axis fixing - multi-sensor adjustment method, such as Figure 8 As shown:

[0093] 1) Coarse adjustment: Install the standard length bar 8 onto the sensor bracket 7 and fix it. Move the slide module 3 to control the axial distance between the standard length bar 8 and the double ball detection bar 9 within 2-5mm. Fix the position of the slide module 3.

[0094] 2) Fine adjustment: Adjust the three-axis moving platform 5 so that the standard length rod 8 located in the axial and radial directions is in complete contact with the spherical surface of the double-ball detection rod 9, and then lock the three-axis moving platform 5. Figure 1 As shown;

[0095] 3) Install the sensor: Remove the standard length bar 8 and install the laser displacement sensor 21 in place.

[0096] Example 4: Test Method for Thermal Elongation and Thermal Deflection of Machine Tool Spindle

[0097] Methods for testing the thermal elongation and thermal displacement of machine tool spindles, such as Figure 9 As shown:

[0098] 1) Install the test spindle: Install the test spindle 16 onto the U-shaped quick-release bracket 14 and fix it with bolts. Then install the assembly onto the spindle test bracket 18 and fix it with bolts.

[0099] 2) Install the test device: Install the double ball test bar 9 onto the static stiffness tool holder 22-2, and then install the tool holder onto the spindle under test 16;

[0100] 3) Sensor installation and debugging: Install the laser displacement sensor 21 according to the three-dimensional section axis-multi-sensor adjustment method;

[0101] 4) Start the test and collect data: Start the spindle and gradually increase it to the maximum speed. Collect data from the axial and radial laser displacement sensors 21 and the temperature data of the spindle under test 16 through the worktable 20.

[0102] 5) Data processing: Based on the data collected by the workbench 20, plot the temperature-axial displacement and temperature-radial displacement curves of the tested spindle and give the thermal elongation and thermal offset of the tested spindle.

[0103] Example 5: Test Method for Axial and Radial Static Stiffness of Machine Tool Spindle

[0104] Methods for testing the axial and radial static stiffness of machine tool spindles, such as Figure 10 As shown:

[0105] 1) Install the test spindle: Install the test spindle 16 onto the U-shaped quick-release bracket 14 and fix it with bolts. Then install the assembly onto the spindle test bracket 18 and fix it with bolts.

[0106] 2) Install the test device: Fix the static stiffness loading block 22-1 to the static stiffness tool holder 22-2 with bolts, then install the double ball test bar 9 to the static stiffness tool holder 22-2, and finally install the static stiffness module 22 to the spindle under test 16.

[0107] 3) Sensor installation and debugging: Install the laser displacement sensor 21 according to the three-dimensional section axis-multi-sensor adjustment method;

[0108] 4) Axial static stiffness test: Extend the axial loading electric cylinder 17 and connect the S-type tension sensor 15, single-bar ball joint 13, loading arm 12 and static stiffness module 22 in sequence; set the axial force value and start loading. After the loading force value stabilizes, collect the data from the laser displacement sensor 21 and S-type tension sensor 15 located in the axial direction through the worktable 20, and calculate the axial static stiffness of the tested spindle.

[0109] 5) Radial static stiffness test: Extend the radial loading electric cylinder 10-3 so that the radial loading head 10-5 is in complete contact with the bottom of the static stiffness loading block 22-1; set the radial force value and start loading. After the loading force value stabilizes, collect the data from the laser displacement sensor 21 and pressure sensor 10-4 located in the radial direction through the worktable 20, and calculate the radial stiffness of the tested spindle.

[0110] Example 6: Test Method for Axial Working Stiffness of Machine Tool Spindle

[0111] Methods for testing the axial working stiffness of machine tool spindles, such as Figure 11 As shown:

[0112] 1) Install the test spindle: Install the test spindle 16 onto the U-shaped quick-release bracket 14 and fix it with bolts. Then install the assembly onto the spindle test bracket 18 and fix it with bolts.

[0113] 2) Install the test device: Connect the working stiffness loading block 11-5 to the working stiffness tool holder 11-7 through the bearing, then install the double ball test bar 9 onto the working stiffness tool holder 11-7, and then install the working stiffness module 11 onto the spindle under test 16.

[0114] 3) Sensor debugging and installation: Install the laser displacement sensor 21 according to the three-dimensional section axis-multi-sensor adjustment method;

[0115] 4) Adjustment of axial loading device: Extend the axial loading electric cylinder 17 and connect it in sequence to the S-type tension sensor 15, single-bar ball joint 13, loading arm 12 and working stiffness module 11;

[0116] 5) Apply axial load and collect data: Set the axial loading force according to the rotational speed of the spindle under test, start with the minimum load, and gradually increase to the maximum load. Collect data from the laser displacement sensor 21 and S-type tension sensor 15 located in the axial direction through the worktable 20.

[0117] 6) Calculate the axial working stiffness: Calculate the axial working stiffness of the test spindle at the corresponding speed based on the data collected by the worktable 20.

[0118] Example 7: Test Method for Radial Working Stiffness of Machine Tool Spindle

[0119] Methods for testing the radial working stiffness of machine tool spindles, such as Figure 11 As shown:

[0120] 1) Install the test spindle: Install the test spindle 16 onto the U-shaped quick-release bracket 14 and fix it with bolts. Then install the assembly onto the spindle test bracket 18 and fix it with bolts.

[0121] 2) Install the test device: Connect the working stiffness loading block 11-5 to the working stiffness tool holder 11-7 through the bearing, then install the double ball test bar 9 onto the working stiffness tool holder 11-7, and then install the working stiffness module 11 onto the spindle under test 16.

[0122] 3) Sensor debugging and installation: Install the laser displacement sensor 21 according to the three-dimensional section axis-multi-sensor adjustment method;

[0123] 4) Radial loading device adjustment: Extend the radial loading electric cylinder 10-3 so that the radial loading head 10-5 is in full contact with the bottom of the working stiffness loading block 22-1;

[0124] 5) Apply radial load and collect data: Set the radial loading force according to the rotational speed of the spindle under test, start with the minimum load, and gradually increase to the maximum load. Collect data from the laser displacement sensor 21 and the pressure sensor 10-4 located in the radial direction through the worktable 20.

[0125] 6) Calculate radial working stiffness: Calculate the radial working stiffness of the test spindle at the corresponding speed based on the data collected by the worktable 20.

Claims

1. A comprehensive performance testing device for machine tool spindles, comprising: Ground level (1), three-dimensional section axis-multi-sensor adjustment module, axial loading unit, radial loading unit (10), loading arm (12), spindle fixing module, static stiffness module (22), working stiffness module (11), detection module and worktable (20); The three-dimensional section axis-multi-sensor adjustment module, the main shaft fixing module and the radial loading unit (10) are positioned and connected to the ground iron (1); the axial loading unit is positioned and connected to the main shaft fixing module; the detection module is positioned and connected to the three-dimensional section axis-multi-sensor adjustment module; the static stiffness module (22) is positioned and connected to the axial loading unit or the radial loading unit (10) through the loading arm (12); The working stiffness module (11) is positioned and connected to the axial loading unit or the radial loading unit (10) through the loading arm (12); The three-dimensional sectional fixed axis-multi-sensor adjustment module includes: a slide module base (2), a slide module (3), a three-axis moving platform heightening frame (4), a three-axis moving platform (5), a sensor bracket fixing seat (6), a sensor bracket (7), and a standard length bar (8); The slide module base (2) is fixedly connected to the ground iron (1) by bolts. The slide module (3) is fixedly connected to the slide module base (2) by bolts. The three-axis moving platform extension frame (4) is fixedly connected to the moving platform on the slide module (3) by bolts. The three-axis moving platform (5) is fixedly connected to the three-axis moving platform extension frame (4) by bolts. The sensor bracket fixing seat (6) is fixedly connected to the three-axis moving platform (5) by bolts. The sensor bracket (7) is an integrated bracket, which is fixedly connected to the sensor bracket fixing seat (6) by bolts. The sensor hole on the sensor bracket (7) is provided with a circular protrusion. The standard length bar (8) and the laser displacement sensor (21) have a corresponding circular groove. By twisting the bolts to reduce the inner diameter of the sensor hole, the standard length bar (8) or the laser displacement sensor (21) can be fixed on the sensor bracket (7). The detection module includes: a laser displacement sensor (21), a double-ball detection rod (9), a collet nut (11-1), and a collet (11-2). The working stiffness module (11) includes: a bearing pressure ring (11-3), a locking nut (11-4), a working stiffness loading block (11-5), an angular contact bearing (11-6), and a working stiffness tool holder (11-7). The working stiffness loading block (11-5) has a fork-shaped structure with a through hole in the middle for installing the angular contact bearing (11-6); the working stiffness loading block (11-5) has square notches on both sides for installing the loading arm (12); the angular contact bearing (11-6) is installed on the working stiffness tool holder (11-7); the outermost cylindrical part of the working stiffness tool holder (11-7) is threaded for installing the locking nut (11-4) and the collet nut (11-1) for clamping the angular contact bearing (11-6); the collet (11-2) is installed inside the working stiffness tool holder (11-7) and clamps the double ball detection rod (9) by cooperating with the collet nut (11-1); The static stiffness module (22) includes: a static stiffness loading block (22-1) and a static stiffness tool holder (22-2); The static stiffness loading block (22-1) has a fork-shaped structure with a through hole in the middle. The static stiffness loading block (22-1) has square notches on both sides for installing the loading arm (12). The static stiffness loading block (22-1) is fixedly connected to the static stiffness tool holder (22-2) by bolts. The collet (11-2) is installed inside the static stiffness tool holder (22-2) and clamps the double ball detection rod (9) by cooperating with the collet nut (11-1).

2. The comprehensive performance testing device for machine tool spindles according to claim 1, characterized in that: The axial loading unit includes: a single-bar ball joint (13), an S-shaped tension sensor (15), and an axial loading electric cylinder (17). The single-bar ball joint (13) is screwed into the threaded through hole at one end of the loading arm (12) and fixed. The S-type tension sensor (15) has internal threaded holes at both ends and is fixedly connected to the axial loading electric cylinder (17) and the single-bar ball joint (13) respectively.

3. The comprehensive performance testing device for machine tool spindles according to claim 2, characterized in that: The radial loading unit (10) includes: a radial loading unit base (10-1), a radial loading unit fixing seat (10-2), a radial loading electric cylinder (10-3), a pressure sensor (10-4), and a radial loading head (10-5). The radial loading unit mounting base (10-2) has an upper fork-shaped structure, and its lower part is fixedly connected to the radial loading unit base (10-1) by bolts; the radial loading electric cylinder (10-3) is fixedly connected to the radial loading unit base (10-1) by bolts; the pressure sensor (10-4) is fixedly connected to the radial loading electric cylinder (10-3) by bolts; the radial loading head (10-5) has a mushroom-shaped structure, with a hemispherical upper part and a stud lower part, which can be screwed into the pressure sensor (10-4) for fixation.

4. The comprehensive performance testing device for machine tool spindles according to claim 3, characterized in that: The spindle fixing module includes: a U-shaped quick-release bracket (14), a spindle test bracket (18), and a spindle test bracket base (19). The spindle test bracket base (19) is fixedly connected to the ground iron (1) by bolts. The spindle test bracket (18) is a T-shaped structure with a U-shaped hole in the middle. Its lower part is fixedly connected to the spindle test bracket base (19) by bolts. The axial loading electric cylinder (17) is distributed on the middle extension structure on both sides of the spindle test bracket (18) and is fixedly connected by bolts. The U-shaped quick-release bracket (14) has a through hole in the middle for installing the tested electric spindle. The combination of the two is fixedly connected to the spindle test bracket (18) by bolts.

5. The comprehensive performance testing device for machine tool spindles according to claim 4, characterized in that: The adjustment method of the three-dimensional sectional fixed axis-multiple sensor is as follows: install the standard length bar (8) on the sensor bracket (7) and fix it, move the slide module (3) to control the axial distance between the standard length bar (8) and the double ball detection bar (9) within 2~5mm, fix the position of the slide module (3); adjust the three-axis moving platform (5) so that the standard length bar (8) located in the axial and radial directions is in complete contact with the spherical surface of the double ball detection bar (9) respectively, then lock the three-axis moving platform (5), remove the standard length bar (8), and install the laser displacement sensor (21) in place.

6. A method for testing the comprehensive performance of a machine tool spindle, using the machine tool spindle comprehensive performance testing device as described in claim 5, comprising: Methods for testing the thermal elongation and thermal offset of machine tool spindles, methods for testing the axial and radial static stiffness of machine tool spindles, methods for testing the axial working stiffness of machine tool spindles, and / or methods for testing the radial working stiffness of machine tool spindles; The aforementioned method for testing the thermal elongation and thermal displacement of a machine tool spindle includes: a. Install the test spindle: Install the test spindle (16) onto the U-shaped quick-release bracket (14) and fix it with bolts. Then install the assembly onto the spindle test bracket (18) and fix it with bolts. b. Install the test device: Install the double ball test bar (9) onto the static stiffness tool holder (22-2), and then install the tool holder onto the spindle under test (16); c. Sensor installation and debugging: Install the laser displacement sensor according to the three-dimensional section axis-multi-sensor adjustment method (21); d. Start the experiment and collect data: Start the spindle and gradually increase it to the maximum speed. Collect data from the axial and radial laser displacement sensors (21) and the temperature data of the spindle under test (16) through the worktable (20); e. Data processing: Based on the data collected by the workbench (20), plot the temperature-axial displacement and temperature-radial displacement curves of the test spindle and give the thermal elongation and thermal offset of the test spindle; The aforementioned method for testing the axial and radial static stiffness of machine tool spindles: a. Install the test spindle: Install the test spindle (16) onto the U-shaped quick-release bracket (14) and fix it with bolts. Then install the assembly onto the spindle test bracket (18) and fix it with bolts. b. Install the test device: Fix the static stiffness loading block (22-1) to the static stiffness tool holder (22-2) with bolts, then install the double ball test bar (9) on the tool holder, and finally install the static stiffness module (22) on the spindle under test (16); c. Sensor installation and debugging: Install the laser displacement sensor according to the three-dimensional section axis-multi-sensor adjustment method (21); d. Axial static stiffness test: The axial loading electric cylinder (17) is extended and connected in sequence to the S-type tension sensor (15), single-bar ball joint (13), loading arm (12) and static stiffness module (22); the axial force value is set and loading is started. After the force value stabilizes, the data of the laser displacement sensor (21) and S-type tension sensor (15) located in the axial direction are collected through the worktable (20) to calculate the axial static stiffness of the test spindle. e. Radial static stiffness test: Operate the radial loading electric cylinder (10-3) to extend, so that the radial loading head (10-5) is in complete contact with the bottom of the static stiffness loading block (22-1); set the radial force value and start loading. After the force value stabilizes, collect the data of the laser displacement sensor (21) and pressure sensor (10-4) located in the radial direction through the worktable (20) and calculate the radial stiffness of the test spindle. The aforementioned method for testing the axial working stiffness of a machine tool spindle includes: a. Install the test spindle: Install the test spindle (16) onto the U-shaped quick-release bracket (14) and fix it with bolts. Then install the assembly onto the spindle test bracket (18) and fix it with bolts. b. Install the test device: Install the double ball test bar (9) onto the working stiffness tool holder (11-7), and then install the working stiffness module (11) onto the spindle under test (16); c. Sensor debugging and installation: Install the laser displacement sensor according to the three-dimensional section axis-multi-sensor adjustment method (21); d. Adjustment of axial loading device: Extend the axial loading electric cylinder (17) and connect the S-type tension sensor (15), single-bar ball joint (13), loading arm (12) and working stiffness module (11) in sequence. e. Apply axial load and collect data: Set the axial loading force according to the rotational speed of the spindle of the test subject, start loading from the minimum load, and gradually increase to the maximum load. Collect data from the laser displacement sensor (21) and S-type tension sensor (15) located in the axial direction through the worktable (20); f. Calculate the axial working stiffness: Calculate the axial working stiffness of the test spindle at the corresponding speed based on the data collected by the worktable (20); The aforementioned method for testing the radial working stiffness of a machine tool spindle includes: a. Install the test spindle: Install the test spindle (16) onto the U-shaped quick-release bracket (14) and fix it with bolts. Then install the assembly onto the spindle test bracket (18) and fix it with bolts. b. Install the test device: Install the double ball test bar (9) onto the working stiffness tool holder (11-7), and then install the working stiffness module (11) onto the spindle under test (16); c. Sensor debugging and installation: Install the laser displacement sensor according to the three-dimensional section axis-multi-sensor adjustment method (21); d. Adjustment of radial loading device: Extend the radial loading electric cylinder (10-3) so that the radial loading head (10-5) is in full contact with the bottom of the working stiffness loading block (11-5); e. Apply radial load and collect data: Set the radial loading force according to the rotational speed of the spindle under test, start loading from the minimum load, and gradually increase to the maximum load. Collect data from the laser displacement sensor (21) and pressure sensor (10-4) located in the radial direction through the worktable (20); f. Calculate radial working stiffness: Calculate the radial working stiffness of the test spindle at the corresponding rotational speed based on the data collected by the worktable (20).

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