High-speed precise bearing dynamic stiffness measuring device

Abstract

The invention relates to a high-speed precise bearing dynamic stiffness measuring device, and belongs to the technical field of bearing dynamic stiffness measurement. A fixing plate of the device comprises a mounting ring and a base, the mounting ring is of an annular structure formed by combining an upper semicircular ring and a lower semicircular ring in a split mode, the lower semicircular ring is located at the top of the base and integrated with the base, and the mounting ring is arranged on a main connecting annular plate in a sleeving mode and clamps and fixes the main connecting annular plate through the mounting ring. The thrust electric cylinder is connected with the main connecting annular plate through a connecting plate; the front end of the thrust electric cylinder extends into an inner cavity of the main connecting annular plate, the spherical floating push head and the force measuring sensor are sequentially assembled at the front end of the thrust electric cylinder, and the bearing push plate is arranged between the floating push head and the test bearing on the rotating mandrel. The device is used for measuring the dynamic stiffness of the high-speed precise bearing, and the dynamic stiffness of the bearing can be measured in various coupling forms such as variable load, variable speed, constant load and constant speed by controlling the rotating speed of the motor and the thrust of the thrust cylinder.

Description

Technical Field

[0001] The invention relates to a high-speed precision bearing dynamic stiffness measuring device, belonging to the technical field of bearing dynamic stiffness measurement. Background Art

[0002] The dynamic stiffness of the bearing is one of the most critical performance parameters in the spindle system, which directly affects the accuracy of the spindle system. Different from the measurement of static stiffness, dynamic stiffness refers to the ability to resist dynamic displacement changes when subjected to alternating loads. Dynamic stiffness is the main indicator for measuring the vibration resistance of the structure. Therefore, studying the dynamic stiffness test of the bearing is more important for accurately obtaining the dynamic characteristics of the spindle bearing system. For the spindle-bearing joint, the dynamic stiffness is affected by many factors, such as bearing preload, bearing pairing method, bearing and spindle matching method, spindle rotation speed, bearing temperature rise, etc. Therefore, it is of great significance to study the performance of the bearing by using a test device to study the change law of the dynamic stiffness of the bearing under different combinations of bearing preload and bearing speed.

[0003] At present, the devices used to study the dynamic stiffness of bearings are all low-speed, and most of the devices used to measure the dynamic stiffness of bearings are non-contact. Summary of the invention

[0004] The purpose of the present invention is to provide a high-speed precision bearing dynamic stiffness measuring device, which is used to measure the dynamic stiffness of high-speed precision bearings. By controlling the motor speed and the thrust of the thrust cylinder, the dynamic stiffness of the bearing can be measured under various coupling forms such as variable load, variable speed, fixed load, and fixed speed.

[0005] The technical solution of the present invention is:

[0006] A high-speed precision bearing dynamic stiffness measuring device, the fixed plate of the device includes a mounting ring and a base, the mounting ring is an annular structure composed of an upper semicircular ring and a lower semicircular ring, the lower semicircular ring is located on the top of the base and is integrated with the base, the mounting ring is sleeved on the main connecting annular plate and the main connecting annular plate is clamped and fixed by the mounting ring, a motor blocking plate is installed at one end of the electromagnetic motor housing, the other end of the electromagnetic motor housing is fixed to one end of the main connecting annular plate by a flange, a connecting plate is installed at the other end of the main connecting annular plate, and a thrust electric cylinder is connected to the main connecting annular plate through the connecting plate; the front end of the thrust electric cylinder extends to the inner cavity of the main connecting annular plate, the spherical floating push head and the force sensor are sequentially assembled at the front end of the thrust electric cylinder, and a bearing push plate is arranged between the floating push head and the test bearing on the rotating core shaft.

[0007] The high-speed precision bearing dynamic stiffness measuring device described above has a bearing push plate with a concave structure. A positioning hole corresponding to a floating push head is provided at the center of the bottom surface of the concave structure of the bearing push plate. The end surface of the concave structure of the bearing push plate corresponds to the end surface of the test bearing. The floating push head is pushed by a thrust electric cylinder to contact the bearing push plate and apply thrust to the test bearing.

[0008] The high-speed precision bearing dynamic stiffness measuring device is provided with three contact displacement sensors on the connecting plate, the three contact displacement sensors are evenly distributed along the circumference of the bearing, the contact displacement sensors are in contact with the outer ring of the test bearing, and the dynamic stiffness change of the test bearing is measured by the contact displacement sensors.

[0009] In the high-speed precision bearing dynamic stiffness measuring device, the base of the fixed plate is fixedly mounted on the vibration-proof plate, and the vibration-proof plate is assembled on the top of the mounting frame.

[0010] The high-speed precision bearing dynamic stiffness measuring device is characterized in that the electromagnetic motor housing and the inner wall of the main connecting annular plate together form an inner cavity of the electromagnetic motor, a horizontal rotating core shaft is provided in the inner cavity, the rotating core shaft is located on the side of the inner cavity of the electromagnetic motor housing, and a motor stator and a motor rotor are installed, the rotating core shaft is located on the side of the inner cavity of the main connecting annular plate, and two groups of test bearings are installed, and a bearing partition is provided between the two groups of test bearings.

[0011] In the high-speed precision bearing dynamic stiffness measuring device, the test bearing is assembled on a rotating mandrel, and the driving form of the rotating mandrel is electromagnetic drive.

[0012] The design concept of the present invention is:

[0013] The bearing of the present invention is driven by an electromagnetic motor to rotate the rotor, thereby driving the bearing to rotate at high speed. The electromagnetic motor is fixed at one end of the test bearing, and is arranged away from the test bearing to reduce the influence of the rotation and heating of the electromagnetic motor on the test. One group of bearings is supported by a rigid flange, and the other group of bearings is supported by an electric loading device, and thrust is applied as needed. The displacement sensor contacts the outer ring of the bearing for measurement. Three displacement sensors are evenly distributed along the circumference of the bearing. The three displacement sensors monitor the stiffness of the outer ring of the bearing in real time, and the average value is taken during operation to make the test result more accurate. When testing, the speed curve parameters and thrust curve parameters are set according to the test conditions to realize the dynamic stiffness measurement of the bearing under variable load, variable speed, constant load and constant speed conditions.

[0014] The advantages and beneficial effects of the present invention are:

[0015] (1) The device of the present invention can ensure the dynamic stiffness measurement of the bearing in various coupling forms such as variable load, variable speed, fixed load, and fixed speed;

[0016] (2) The present invention uses a contact displacement sensor to measure bearing displacement, which has better accuracy;

[0017] (3) The electromagnetic motor is arranged away from the bearing during design to reduce the influence of motor heating on the bearing stiffness measurement results. The deformation of two groups of bearings is measured each time to amplify the test results and improve the test accuracy.

[0018] (4) Under electromagnetic drive, the rotating spindle speed can reach 30,000 r / min, providing a stable speed for testing.

[0019] (5) The device of the present invention uses an electric cylinder to push the force sensor and the bearing push plate forward. After the bearing push plate contacts the bearing, it feeds back the pressure. According to the bearing working condition and bearing model, the relevant parameters such as the loading curve and the speed curve are set. The following four testing methods can be used: constant thrust and constant speed to test the bearing dynamic stiffness; variable load thrust and constant speed to test the bearing dynamic stiffness; constant thrust and variable speed to test the bearing dynamic stiffness; variable load thrust and variable speed to test the bearing dynamic stiffness. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1-Figure 2 It is the structural design diagram of the present invention. Among them, Figure 1 For the axonometric drawing, Figure 2 It is a cross-sectional view.

[0021] The reference numerals in the figure are: 1. mounting frame, 2. anti-vibration plate, 3. electromagnetic motor housing, 4. fixing plate (401 mounting ring, 402 base), 5. connecting plate, 6. thrust electric cylinder, 7. contact displacement sensor, 8. motor blocking plate, 9. motor stator, 10. motor rotor, 11. test bearing, 12. bearing push plate (1201 positioning hole), 13. floating push head, 14. force sensor, 15. bearing partition plate, 16. main connecting annular plate, 17. rotating core shaft. DETAILED DESCRIPTION

[0022] like Figure 1-Figure 2 As shown, the present invention proposes a high-speed precision bearing dynamic stiffness measuring device, which mainly includes a mounting frame 1, an anti-vibration plate 2, an electromagnetic motor housing 3, a fixing plate 4, a connecting plate 5, a thrust electric cylinder 6, a contact displacement sensor 7, a motor plugging plate 8, a motor stator 9, a motor rotor 10, a test bearing 11, a bearing push plate 12, a floating push head 13, a force sensor 14, a bearing partition plate 15, a main connecting annular plate 16, a rotating mandrel 17, etc. The specific structure is as follows:

[0023] The top of the mounting frame 1 is equipped with an anti-vibration plate 2, which is used to prevent the vibration of the device from interfering with the vibration of the ground. The fixed plate 4 includes a mounting ring 401 and a base 402. The mounting ring 401 is a ring-shaped structure composed of an upper semicircular ring and a lower semicircular ring. The lower semicircular ring is located on the top of the base 402 and is integrated with the base 402. The anti-vibration plate 2 is designed with mounting holes, which are fixed to the base 402 of the fixed plate 4. The mounting ring 401 is sleeved on the main connecting annular plate 16 and the main connecting annular plate 16 is clamped and fixed by the mounting ring 401. The motor plug 8 is installed at one end of the electromagnetic motor housing 3, and the other end of the electromagnetic motor housing 3 is connected and fixed to one end of the main connecting annular plate 16 by a flange. The other end of the main connecting annular plate 16 is installed with a connecting plate 5, and the thrust electric cylinder 6 is connected to the main connecting annular plate 16 through the connecting plate 5.

[0024] The electromagnetic motor housing 3 and the inner wall of the main connecting annular plate 16 together form the inner cavity of the electromagnetic motor, and a horizontal rotating core shaft 17 is arranged in the inner cavity. The rotating core shaft 17 is located on the side of the inner cavity of the electromagnetic motor housing 3 and the motor stator 9 and the motor rotor 10 are installed. The rotating core shaft 17 is located on the side of the inner cavity of the main connecting annular plate 16 and two groups of test bearings 11 are installed. A bearing partition plate 15 is arranged between the two groups of test bearings 11; the front end of the thrust electric cylinder 6 extends to the inner cavity of the main connecting annular plate 16, and the spherical floating thrust head 13 and the force sensor 14 are sequentially assembled on the thrust At the front end of the electric cylinder 6, a concave structure bearing push plate 12 is arranged between the floating push head 13 and the test bearing 11. A positioning hole 1201 corresponding to the floating push head 13 is provided at the center of the bottom surface of the concave structure of the bearing push plate 12. A part of the front end of the floating push head 13 is embedded in the positioning hole 1201. The concave structure end surface of the bearing push plate 12 corresponds to the end surface of the test bearing 11. The floating push head 13 is pushed by the thrust electric cylinder 6 to contact the bearing push plate 12 and apply thrust to the test bearing 11. The applied thrust value is fed back in real time through the force sensor 14. In addition, three contact displacement sensors 7 are arranged on the connecting plate 5. The three contact displacement sensors 7 are evenly distributed along the circumference of the bearing. The contact displacement sensors 7 are in contact with the outer ring of the test bearing 11. The contact displacement sensors 7 can measure the dynamic stiffness changes of the two groups of bearings, and the measurement results are amplified to make the measurement results more accurate.

[0025] In the present invention, the test bearing 11 is assembled on the rotating mandrel 17, the driving form of the rotating mandrel 17 is electromagnetic drive, and the test bearing is arranged away from the electromagnetic motor, so as to avoid the influence of the heating of the electromagnetic motor on the stiffness measurement result, and it is easier to realize the bearing stiffness test. The two groups of test bearings 11 are separated by a bearing partition plate 15, and the motor rotor 10 is welded on the rotating mandrel 17. The test bearing 11 is driven by the electromagnetic motor to rotate the motor rotor 10, thereby driving the test bearing 11 to rotate at a high speed, and the rotating mandrel 17 is controlled by the speed curve. Through the coordination of the thrust curve and the speed curve, the dynamic stiffness test of the device under the multi-coupling conditions of variable speed, variable load, constant speed and constant load is realized.

[0026] The test results show that the bearing arrangement based on the electromagnetic motor principle and the electric cylinder loading form can realize the dynamic stiffness measurement of the bearing under variable load, variable speed, constant load and constant speed. The bearing displacement measuring device is used to measure the displacement of the outer ring of the bearing under force, so as to calculate the dynamic stiffness of the bearing. The device adopts high-frequency sampling and can provide real-time feedback on the change of bearing displacement. The measuring device adopts a contact measuring device for measurement, which has higher repeatability accuracy than the non-contact measuring device.

Claims

1. A high-speed precision bearing dynamic stiffness measurement device, characterized in that: The fixed plate of the device includes a mounting ring and a base. The mounting ring is an annular structure composed of an upper semicircular ring and a lower semicircular ring. The lower semicircular ring is located on the top of the base and is integrated with the base. The mounting ring is sleeved on the main connecting annular plate and the main connecting annular plate is clamped and fixed by the mounting ring. A motor blocking plate is installed at one end of the electromagnetic motor housing. The other end of the electromagnetic motor housing is fixed to one end of the main connecting annular plate by a flange. A connecting plate is installed at the other end of the main connecting annular plate. The thrust electric cylinder is connected to the main connecting annular plate through the connecting plate. The front end of the thrust electric cylinder extends to the inner cavity of the main connecting annular plate. The spherical floating push head and the force sensor are sequentially assembled at the front end of the thrust electric cylinder. A bearing push plate is arranged between the floating push head and the test bearing on the rotating core shaft.

2. The high-speed precision bearing dynamic stiffness measuring device according to claim 1, characterized in that: The bearing push plate is a concave structure. A positioning hole corresponding to the floating push head is opened at the center of the bottom surface of the concave structure of the bearing push plate. The end face of the concave structure of the bearing push plate corresponds to the end face of the test bearing. The floating push head is pushed by the thrust electric cylinder to contact the bearing push plate and apply thrust to the test bearing.

3. The high-speed precision bearing dynamic stiffness measuring device according to claim 1, characterized in that: Three contact displacement sensors are arranged on the connecting plate, the three contact displacement sensors are evenly distributed along the circumference of the bearing, the contact displacement sensors are in contact with the outer ring of the test bearing, and the dynamic stiffness change of the test bearing is measured by the contact displacement sensors.

4. The high-speed precision bearing dynamic stiffness measuring device according to claim 1, characterized in that: The base of the fixing plate is fixed on the anti-vibration plate, and the anti-vibration plate is assembled on the top of the mounting frame.

5. The high-speed precision bearing dynamic stiffness measuring device according to claim 1, characterized in that: The electromagnetic motor housing and the inner wall of the main connecting annular plate together form an inner cavity of the electromagnetic motor, in which a horizontal rotating core shaft is provided. The rotating core shaft is located on the side of the inner cavity of the electromagnetic motor housing and is used to install a motor stator and a motor rotor. The rotating core shaft is located on the side of the inner cavity of the main connecting annular plate and is used to install two sets of test bearings. A bearing partition is provided between the two sets of test bearings.

6. The high-speed precision bearing dynamic stiffness measuring device according to claim 1, characterized in that: The test bearing is assembled on a rotating mandrel, and the driving form of the rotating mandrel is electromagnetic drive.

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