Device and method for measuring friction performance of rolling bearing for complex service conditions
By simulating the space environment inside a vacuum chamber and combining high-precision gratings and reading heads for measurement, the problem of assessing the changes in the friction performance of rolling bearings under extreme conditions, which is difficult in existing technologies, has been solved, and high-precision, full-lifecycle friction performance measurement and early warning have been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HARBIN INST OF TECH
- Filing Date
- 2025-12-26
- Publication Date
- 2026-04-21
AI Technical Summary
Existing technologies struggle to accurately assess the complex frictional behavior of rolling bearings in extremely harsh service environments, especially the changes in frictional performance under conditions such as repeated rapid acceleration and deceleration, given the requirements for long service life and high reliability in space.
A rolling bearing friction performance measurement device for complex service conditions was designed, including a main shaft, the bearing under test, the bearing housing, a vacuum chamber, a charged particle emission source and a heating device to simulate the space environment. The main shaft is driven to rotate by a coil and a permanent magnet. The speed is measured in real time by a high-precision grating and a reading head, and the friction performance parameters are calculated.
It improves the accuracy and realism of friction performance measurement, enables continuous measurement of friction performance under transient conditions, removes range limitations, expands the scope of application, provides accurate measurement of friction coefficient changes throughout the bearing's entire life cycle, and provides early warning of abnormal wear and lubrication failure.
Smart Images
Figure CN121899005A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of high-precision rolling bearing tribological performance measurement technology, specifically to a rolling bearing friction performance measurement device and method for complex service conditions. Background Technology
[0002] With the continuous growth of the number of satellites in orbit in my country and the deepening of space attack and defense technologies, the demand for high-precision stable control, long-life reliable service, and large-angle rapid maneuvering of spacecraft is becoming increasingly urgent. Rolling bearings, as key basic components of satellite momentum wheels, gyroscopes, and other precision space instruments, have their frictional performance as a core indicator for evaluating overall bearing performance, directly affecting temperature rise, energy consumption, and accuracy, and are crucial for ensuring the long-term stable operation of mechanical equipment on the space station. Current methods for measuring and evaluating the frictional performance of rolling bearings have significant limitations: the industry generally uses a single frictional torque to characterize the bearing's frictional performance, and this can only be implemented under discrete measurements under constant-speed steady-state conditions (such as the constant-speed test method recommended by GB / T 32562-2016). However, under the requirements of long lifespan and high reliability in space, the complex frictional behavior of bearings used in satellite bias momentum wheels and reaction flywheels in extremely harsh service environments presents a challenge for accurate evaluation. Therefore, this invention develops a novel measuring device for high-precision measurement and evaluation of the changes in the frictional performance of rolling bearings under extreme conditions such as repeated rapid acceleration and deceleration. Summary of the Invention
[0003] The purpose of this invention is to provide a rolling bearing friction performance measurement device and method for simulating space environment and improving the reliability and extreme condition applicability of precision rolling bearings in the aerospace field, which is suitable for complex service conditions.
[0004] To achieve the above objectives, the present invention adopts the following technical solution: A rolling bearing friction performance measuring device for complex service conditions includes a spindle, with each end of the spindle connected to a pair of bearings to be tested. The pair of bearings to be tested are coaxially fixed on a pair of bearing housings via bearing adapters. Each pair of bearing housings is equipped with a space environment simulation device, which includes a vacuum chamber containing a charged particle emission source. The spindle is equipped with a drive device and a data acquisition device, which is connected to a host computer.
[0005] Preferably, one end of the spindle extends beyond the bearing being tested, and a flywheel is fixedly mounted on the end of the spindle extending beyond the bearing being tested; the flywheel and a pair of bearings being tested are coaxially fitted together, and the flywheel is mounted inside the vacuum chamber.
[0006] Preferably, a pair of vacuum chambers are provided, each located on the outside of a pair of bearing seats; each pair of vacuum chambers is connected to a vacuum pumping device.
[0007] Preferably, the drive device includes a coil wound around the middle section of the main shaft; a permanent magnet is provided on the middle section of the main shaft, and the permanent magnet is configured in conjunction with the coil.
[0008] Preferably, multiple heating devices are evenly distributed around the outer circumference of the bearing housing, and the interior of the vacuum chamber is coated with high-temperature black paint; a temperature measuring and control element is provided on the end face of the bearing adapter, and the temperature measuring and control element is connected to the host computer signal.
[0009] Preferably, the data acquisition device includes a high-precision grating disposed in the middle section of the spindle, and a reading head disposed in cooperation with the high-precision grating; the reading head is connected to the host control computer via signal.
[0010] A method for measuring the frictional properties of rolling bearings includes the following steps: S1. Test preparation: Select a suitable bearing adapter according to the size of the bearing to be tested, fix the two bearings to be tested on the bearing housing through the bearing adapter, and install the spindle between the two bearings; fix the flywheel on the end of the spindle that extends beyond the bearing to be tested, and then close the vacuum chamber; S2. Manufacturing and testing environment: The air in the vacuum chamber is discharged to the outside through two stages of coarse and fine evacuation by the vacuum pumping device, so that a high vacuum chamber environment is formed in the vacuum chamber; the charged particle emission source is turned on to provide a particle radiation environment for the bearing under test; the heating device is turned on and the temperature of the bearing under test is monitored by the temperature measurement and control element until the preset temperature is reached. S3. Start Test: Power on the coil, which works with the permanent magnet on the spindle to drive the spindle to start rotating using the principle of a brushless motor; the angular position and angular velocity information of the spindle are read in real time through the reading head and high-precision grating and transmitted to the host computer. S4. Calculate friction performance: The host computer captures the speed change characteristics of the bearing under test during continuous operation based on the data information transmitted by the reading head, and calculates the friction performance parameters of the bearing under test.
[0011] Preferably, the specific process of calculating the frictional properties in step S4 includes: If the total kinetic energy of the shaft system is uniformly converted into the rotational speed of the main shaft, then the total kinetic energy of the shaft system is... E k for: (1) in, J s , J b , J f These are the moments of inertia of the spindle, bearings, and flywheel, respectively. ω i The angular velocity of the main spindle and the bearing being measured; The frictional power of the bearing under test can be obtained by differentiating the kinetic energy of the shaft system. P b : (2) The angular velocity of the bearings is acquired in real time using a high-precision grating. Based on the relationship between frictional power and angular velocity, the frictional torque of the two tested bearings can be obtained. M AB for: (3) The friction coefficient of the tested bearing can be obtained from the relationship between frictional torque, normal load, and radius. μ for: (4) in, F n The normal load is the sum of the masses of the main shaft and the flywheel. Different normal loads can be applied by changing the mass of the flywheel. R The bearing center radius; To further explore the changes in frictional performance of the tested bearing during extreme acceleration / deceleration and rapid start / stop processes, the angular velocity of the tested bearing was differentiated to obtain its angular acceleration. a : (5) The angular acceleration of the bearing under test can be obtained by further differentiating the angular acceleration. a’ : (6).
[0012] The beneficial effects of this invention are: This invention simulates the actual operating environment of high-precision rolling bearings used in spacecraft such as satellite momentum wheels by placing the bearing under test inside a vacuum chamber and setting up a charged particle emission source and heating device. Furthermore, it simulates the structure of a brushless motor by using coils and permanent magnets to drive the main shaft to rotate, thereby simulating the frequent start-stop, rapid acceleration and deceleration processes of the bearing under conditions such as microgravity, high and low temperatures, and particle radiation in space. This improves the realism of the bearing measurement process and obtains data that is closer to real-world usage results.
[0013] This invention employs a high-precision grating combined with a reading head to measure speed transiently, fundamentally achieving a leap from steady-state force measurement to transient speed measurement. This significantly improves the resolution accuracy of friction performance in high-end precision bearings, increasing measurement accuracy by 1-2 orders of magnitude. This invention can measure bearing friction performance under transient continuous change conditions, and because it directly measures bearing speed, it also removes limitations on the measurement range, expanding the applicability of the device.
[0014] The measuring device provided by this invention can acquire the change in friction coefficient throughout the entire life cycle of a bearing, providing guidance for the design and manufacturing process of high-end precision bearings. In addition to measuring the friction torque and friction coefficient of a bearing, this invention can also further measure the acceleration and jerk (jump) of the bearing, enabling precise detection of minute changes in the friction performance of high-end bearings used in satellite momentum wheels. The friction coefficient is a curve that changes continuously with speed. By using typical bearing speed, acceleration, and jerk signals, early warnings can be provided for abnormal wear, lubrication failure, and defect initiation in satellite bearings. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the overall structure of Embodiment 1 of the present invention; Figure 2 For the present invention Figure 1 Partial sectional view at the AA mark in the middle; Figure 3 This is a cross-sectional view of the bearing adapter in Embodiment 2 of the present invention; Figure 4 This is a cross-sectional view of the bearing adapter in Embodiment 3 of the present invention; Figure 5 This is a cross-sectional view of the bearing adapter in Embodiment 4 of the present invention.
[0016] In the diagram: 1. Charged particle emission source; 2. Vacuum pumping device; 3. Flywheel; 4. Bearing under test; 5. Bearing adapter; 6. Bearing housing; 7. Vacuum chamber; 8. Coil; 9. Main shaft; 10. Grating; 11. Reading head; 12. Data transmission cable; 13. Host control computer; 14. Heating device; 15. Temperature measurement and control element; 16. Sealing ring. Detailed Implementation
[0017] Example 1 The following is a further explanation of the present invention in conjunction with specific embodiments, such as... Figure 1 As shown, this embodiment is a rolling bearing friction performance measuring device for complex service conditions. It mainly includes a pair of bearing seats 6, on which a bearing adapter 5 is fixedly mounted. The bearing to be tested 4 is fixedly mounted through the bearing adapter 5. The outer ring of the bearing to be tested 4 and the inner surface of the bearing adapter 5 are in a basic shaft transition fit. The two bearings to be tested 4 are coaxially arranged, and a main shaft 9 is arranged between the bearings to be tested 4. The shaft system can adopt a vertical or horizontal layout. In this embodiment, a vertical layout is preferred, so that the axis of the bearing to be tested 4 is perpendicular to the horizontal plane.
[0018] The bearing housing 6, bearing adapter 5, and the bearing under test 4 are all placed inside a space environment simulation device. The space environment simulation device includes a vacuum chamber 7, which can form a sealed structure with the outside world and simulate the actual working space environment of the bearing under test 4 inside. A vacuum pumping device 2 is connected to the vacuum chamber 7, which can exhaust the air inside the vacuum chamber 7 to the outside world, so that a high vacuum cavity is formed inside the vacuum chamber 7. Two vacuum chambers 7 are provided to cooperate with the two bearing housings 6. Through holes are opened on the opposite side of the two vacuum chambers 7 for the main shaft 9 to pass through, and a specially made pressure-resistant and temperature-resistant sealing ring 16 is set at the through hole for sealing. One end of the main shaft 9 is connected to the inner ring of one bearing under test 4, and the other end passes through and is connected to the inner ring of the other bearing under test 4. A flywheel 3 is fixedly connected to the end of the main shaft 9 that extends beyond the bearing under test 4. The main shaft 9, the inner rings of the two bearings under test 4, and the flywheel 3 can rotate synchronously.
[0019] A charged particle emission source 1 is installed inside the vacuum chamber 7. The charged particle emission source 1 can continuously emit charged particles towards the bearing 4 under test to simulate the particle radiation environment in actual operating conditions; for example... Figure 2 As shown, four heating devices 14 are evenly arranged around the circumference of the outer side of the bearing housing 4. The heating devices 14 can directly heat the bearing housing 4, and indirectly heat the bearing under test 4 through the bearing adapter 5. The temperature of the bearing under test 4 can also be directly controlled in the high vacuum chamber environment. Four temperature measuring and control elements 15 are evenly distributed on the end face of the bearing adapter 5, which can monitor the temperature of the bearing under test 4 in real time, so as to control the working temperature of the bearing under test during the test. The inner side of the vacuum chamber 7 is coated with high-temperature black paint, which can prevent the internal heat from dissipating to the outside through radiation, improve the heat preservation performance of the chamber, and ensure the bearing temperature in the test environment.
[0020] like Figure 1 As shown, a coil 8 is arranged in the middle section of the main shaft 9, and the coil 8 is coaxially arranged around the main shaft 9. A permanent magnet is arranged at the corresponding position in the middle section of the main shaft 9. The coil 8 and the permanent magnet can form a structure similar to a brushless motor, thereby driving the main shaft to rotate around the axis. A circular grating 10 is also arranged in the middle section of the main shaft 9, and a reading head 11 is arranged on one side corresponding to the grating 10. When the main shaft 9 rotates, it will drive the grating 10 to rotate together. At this time, the reading head 11 can read the reading on the grating 10 in real time to obtain information such as the angle position and speed of the main shaft 9. The reading head 11 is connected to the host control computer 13 through the data transmission cable 12. The host control computer 13 can calculate the motion parameters of the main shaft 9 based on the information read by the reading head 11, and then calculate the friction performance of the tested bearing 4.
[0021] Example 2 This embodiment describes a method for measuring the friction performance of rolling bearings based on the rolling bearing friction performance measuring device proposed in Embodiment 1, including the following steps: S1. Test Preparation: Select a suitable bearing adapter 5 according to the size of the bearing 4 to be tested. Secure the two bearings 4 to be tested onto the two bearing seats 6 using the bearing adapter 5, and install the spindle 9 between the two bearings. Figure 3 As shown, in this embodiment, a bearing adapter 5 with an inner diameter of 72mm is used to install the bearing 4 under test; the flywheel is fixedly installed on the end of the main shaft 9 that extends beyond the bearing 4 under test, and then the vacuum chamber 7 is closed and sealed.
[0022] S2. Manufacturing and testing environment: The air in the vacuum chamber 7 is discharged to the outside through two stages of coarse pumping and fine pumping by the vacuum pumping device 2, so that a high vacuum cavity environment is formed in the vacuum chamber 7; the charged particle emission source 1 is turned on to provide a particle radiation environment for the bearing under test 4; the heating device 14 is turned on, and the temperature of the bearing under test 4 is monitored by the temperature measuring and control element 15 until the preset temperature is reached.
[0023] S3. Start test: Power on coil 8, which works with the permanent magnet on spindle 9 to drive spindle 9 to start rotating through the principle of brushless motor; read the angular position and angular velocity information of spindle 9 in real time through reading head 11 and high-precision grating 10, and transmit it to upper control computer 13.
[0024] S4. Calculation of Friction Performance: The host control computer 13 captures the speed change characteristics of the tested bearing 4 during continuous operation based on the data information transmitted by the reading head 11, and calculates the friction performance parameters of the tested bearing 4. The kinetic energy of the shaft system can be obtained through the speed of the shaft system. The friction power of the tested bearing 4 can be obtained by differentiating the kinetic energy. The friction torque of the shaft system can be obtained through the relationship between friction power and angular velocity in physics. The friction coefficient of the tested bearing 4 can be obtained based on the relationship between friction torque, normal radius, and load. The specific process includes: For ease of calculation, the total kinetic energy of the shaft system is uniformly converted into the rotational speed of the main shaft 9. Since the main shaft 9 and the inner ring of the bearing 4 being measured are fixedly connected, their rotational speeds are the same. The total kinetic energy of the shaft system... E k for: (1) in, J s , J b , J f These are the moments of inertia of the spindle, bearings, and flywheel, respectively. ω i The angular velocity of the main spindle and the bearing being measured.
[0025] The frictional power of the bearing under test can be obtained by differentiating the kinetic energy of the shaft system. P b : (2) The angular velocity of the bearings is acquired in real time using a high-precision grating. Based on the relationship between frictional power and angular velocity, the frictional torque of the two tested bearings can be obtained. M AB for: (3) The friction coefficient of the tested bearing can be obtained from the relationship between frictional torque, normal load, and radius. μ for: (4) in, F n The normal load is the sum of the masses of the main shaft 9 and the flywheel 3. Different normal loads can be applied by changing the mass of the flywheel 3. R The radius is the center radius of the bearing.
[0026] To further explore the changes in frictional performance of the tested bearing during extreme acceleration / deceleration and rapid start / stop processes, the angular velocity of the tested bearing was differentiated to obtain its angular acceleration. a : (5) The angular acceleration of the bearing under test can be obtained by further differentiating the angular acceleration. a’ : (6).
[0027] Example 3 The difference between this embodiment and embodiment 2 is that, as Figure 4 As shown, in this embodiment, a bearing adapter 5 with an inner diameter of 62mm is used to adapt to the bearings 4 of different sizes for testing.
[0028] Example 4 The difference between this embodiment and embodiment 3 is that, as Figure 5 As shown, in this embodiment, a bearing adapter 5 with an inner diameter of 52mm is used to adapt to the bearings 4 of different sizes for testing.
[0029] The above description is merely a further explanation of the present invention in conjunction with specific embodiments. All descriptions made do not imply any limitation on the scope of protection of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A device for measuring the frictional performance of rolling bearings under complex service conditions, comprising a spindle, characterized in that: The two ends of the spindle are respectively installed in a pair of bearings under test, and the pair of bearings under test are coaxially fixed on a pair of bearing seats through bearing adapters; a space environment simulation device is provided on the outside of each pair of bearing seats, the space environment simulation device includes a vacuum chamber, and a charged particle emission source is provided in the vacuum chamber; a drive device and a data acquisition device are provided on the spindle, and the data acquisition device is connected to a host control computer.
2. The rolling bearing friction performance measuring device for complex service conditions according to claim 1, characterized in that: One end of the main shaft extends beyond the bearing being tested, and a flywheel is fixedly mounted on the end of the main shaft that extends beyond the bearing being tested; the flywheel and a pair of bearings being tested are coaxially coupled, and the flywheel is located inside the vacuum chamber.
3. The rolling bearing friction performance measuring device for complex service conditions according to claim 2, characterized in that: The vacuum chambers are provided in pairs, each located on the outside of a pair of bearing seats; each pair of vacuum chambers is connected to a vacuum pumping device.
4. The rolling bearing friction performance measuring device for complex service conditions according to claim 1, characterized in that: The drive device includes a coil wound around the middle section of the main shaft; A permanent magnet is provided on the middle section of the main shaft, and the permanent magnet is configured in conjunction with the coil.
5. The rolling bearing friction performance measuring device for complex service conditions according to claim 1, characterized in that: Multiple heating devices are evenly distributed around the outer circumference of the bearing housing, and the interior of the vacuum chamber is coated with high-temperature black paint; a temperature measuring and control element is provided on the end face of the bearing adapter, and the temperature measuring and control element is connected to the host computer signal.
6. The rolling bearing friction performance measuring device for complex service conditions according to claim 1, characterized in that: The data acquisition device includes a high-precision grating disposed in the middle section of the spindle, and a reading head disposed in cooperation with the high-precision grating; the reading head is connected to the host control computer via signal.
7. The method for measuring the friction performance of rolling bearings using the rolling bearing friction performance measuring device according to claims 1-6, characterized in that, Includes the following steps: S1. Test preparation: Select a suitable bearing adapter according to the size of the bearing to be tested, fix the two bearings to be tested on the bearing housing through the bearing adapter, and install the spindle between the two bearings; fix the flywheel on the end of the spindle that extends beyond the bearing to be tested, and then close the vacuum chamber; S2. Manufacturing and testing environment: The air in the vacuum chamber is discharged to the outside through two stages of coarse and fine evacuation by the vacuum pumping device, so that a high vacuum chamber environment is formed in the vacuum chamber; the charged particle emission source is turned on to provide a particle radiation environment for the bearing under test; the heating device is turned on and the temperature of the bearing under test is monitored by the temperature measurement and control element until the preset temperature is reached. S3. Start Test: Power on the coil, which works in conjunction with the permanent magnet on the spindle to drive the spindle to start rotating using the principle of a brushless motor; the angular position and angular velocity information of the spindle are read in real time through the reading head and high-precision grating and transmitted to the host computer. S4. Calculate friction performance: The host computer captures the speed change characteristics of the bearing under test during continuous operation based on the data information transmitted by the reading head, and calculates the friction performance parameters of the bearing under test.
8. The method for measuring the frictional performance of rolling bearings according to claim 7, characterized in that: The specific process of calculating the frictional properties in step S4 includes: If the total kinetic energy of the shaft system is uniformly converted into the rotational speed of the main shaft, then the total kinetic energy of the shaft system is... E k for: (1) in, J s , J b , J f These are the moments of inertia of the spindle, bearings, and flywheel, respectively. ω i The angular velocity of the main spindle and the bearing being measured; The frictional power of the bearing under test can be obtained by differentiating the kinetic energy of the shaft system. P b : (2) The angular velocity of the bearings is acquired in real time using a high-precision grating. Based on the relationship between frictional power and angular velocity, the frictional torque of the two tested bearings can be obtained. M AB for: (3) The friction coefficient of the tested bearing can be obtained from the relationship between frictional torque, normal load, and radius. μ for: (4) in, F n For normal load, R The bearing center radius; To further explore the changes in frictional performance of the tested bearing during extreme acceleration / deceleration and rapid start / stop processes, the angular velocity of the tested bearing was differentiated to obtain its angular acceleration. a : (5) The angular acceleration of the bearing under test can be obtained by further differentiating the angular acceleration. a’ : (6)。