Non-contact force loading device and loading method for high-speed precise main shaft

Abstract

The invention relates to the technical field of main shaft performance testing, in particular to a non-contact force loading device and a non-contact force loading method for a high-speed precise main shaft. A movable magnet mechanism is mounted on the main shaft through a mounting base body and drives a movable magnet to rotate; one loading mechanism and the main shaft are coaxially arranged, and the corresponding fixed magnet can be axially close to or far away from the axial force movable magnet so as to axially load the movable magnet mechanism through magnetic force; the other loading mechanism is perpendicular to the axis of the main shaft, and the corresponding fixed magnet can be radially close to or far away from the radial force movable magnet so as to radially load the movable magnet mechanism through magnetic force; the non-contact loading device has the beneficial effects that non-contact loading of the main shaft is realized by utilizing magnetic force, so that the main shaft rotating at a high speed cannot be influenced by contact friction, and the temperature of the main shaft cannot be changed due to high-pressure airflow loading. And all magnets can be permanent magnets, so that the main shaft cannot be heated due to an electromagnetic heat generation phenomenon, and the test result of the main shaft cannot be influenced.

Description

Technical Field

[0001] This invention relates to the technical field of spindle performance testing, and more particularly to a non-contact force loading device and method for high-speed precision spindles. Background Technology

[0002] High-speed precision spindles are one of the key components of precision and ultra-precision machine tools. Under working conditions, the machining tool is mounted on the working end of the spindle, and the spindle drives the machining tool to form a high-speed, stable rotational motion, thereby achieving precision machining of parts. Therefore, the accuracy and stability of the spindle under working speed and load conditions are the foundation and prerequisite for achieving precision and ultra-precision machining of parts.

[0003] Under operating conditions, the spindle primarily bears axial and radial loads. Different spindle speeds and load conditions directly affect the spindle's accuracy, thus influencing the machining precision of parts. To determine the impact of different speeds and load conditions on the precision spindle's accuracy, force loading experiments need to be conducted on the spindle under different speed conditions, and the deformation error of the spindle under corresponding conditions needs to be measured. This yields the true state of the spindle under corresponding operating conditions, providing experimental data for precision and ultra-precision machining of parts.

[0004] Currently, there are many methods for applying force to a spindle, such as static and dynamic contact loading, high-pressure gas loading, electromagnet magnetic loading, and actual working loading. However, in static and dynamic contact loading, the spindle cannot rotate, so it is impossible to obtain the influence of spindle speed and force coupling on spindle accuracy. High-pressure gas loading devices are relatively complex, with low loading accuracy and stability. Furthermore, the high-pressure gas cools the spindle's working end, failing to accurately reflect the impact of temperature on spindle error under working conditions. Electromagnet magnetic loading devices are large and complex, and magnetic induction raises the electromagnet's temperature, affecting the spindle's temperature and accuracy; therefore, it is unsuitable for force loading experiments on high-speed precision spindles. Actual working loading accurately reflects the spindle's load under working conditions; however, the loading process requires machine tools, actual processing materials, and other auxiliary conditions, making it complex and extremely costly. Therefore, this force loading method is rarely used. Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a non-contact force loading device and loading method for high-speed precision spindles, which solves the technical problem that the loading devices in the prior art cannot apply high-precision radial and axial forces to the spindle under rotating conditions.

[0007] (II) Technical Solution

[0008] To achieve the above objectives, the main technical solutions adopted by the present invention include:

[0009] In a first aspect, the present invention provides a non-contact force loading device for a high-speed precision spindle, comprising:

[0010] The moving magnet mechanism includes a mounting base that can be detachably connected to the main shaft at one end, an axial force moving magnet fixedly connected to the other end of the mounting base, and a radial force moving magnet fixedly connected to the radial outer edge of the mounting base, all three of which are coaxial with the main shaft.

[0011] Both loading mechanisms include a fixed magnet, a force sensor, and a distance adjustment component connected in sequence. The distance adjustment component is adapted to drive the fixed magnet to slide along the length direction of the loading mechanism, and the force sensor is adapted to detect the loading force of the fixed magnet.

[0012] The main spindle can drive the moving magnet mechanism to rotate axially; a loading mechanism is set coaxially with the main spindle, and the corresponding fixed magnet can move axially closer to or away from the axial force moving magnet to load the moving magnet mechanism axially through magnetic force; another loading mechanism is perpendicular to the main spindle axis, and the corresponding fixed magnet can move radially closer to or away from the radial force moving magnet to load the moving magnet mechanism radially through magnetic force; the corresponding fixed magnets are kept separate from the corresponding axial force moving magnets and radial force moving magnets.

[0013] In one technical solution of the present invention, the axial force moving magnet and the radial force moving magnet are both opposite to the corresponding fixed magnet, either with the same pole or opposite pole.

[0014] In one technical solution of the present invention, the radial force moving magnet is a ring magnet to simulate the machining condition of the main bearing being subjected to continuous radial force.

[0015] In one technical solution of the present invention, the radial force moving magnet is a fan-shaped annular magnet, and there are multiple magnets evenly distributed around the outer edge of the mounting base to simulate the machining condition of the main bearing carrying intermittent radial force.

[0016] In one technical solution of the present invention, the number of fan-shaped magnets is n, where n is an integer and 2≤n≤6, and they are evenly distributed on the radial outer edge of the mounting base.

[0017] In one technical solution of the present invention, the fan-shaped annular magnet is detachably connected to the mounting base so as to simulate machining tools with different numbers of cutting edges by using fan-shaped annular magnets in different combinations.

[0018] In one technical solution of the present invention, the solid between the axial force magnet and the radial force magnet of the mounting base is made of non-magnetic material.

[0019] In one technical solution of the present invention, the moving magnet mechanism further includes an isolation flange fixedly connected to the mounting base and located between the axial force moving magnet and the radial force moving magnet, the isolation flange being made of a non-magnetic material.

[0020] Secondly, the present invention provides a non-contact force loading method, applied to the non-contact force loading device for high-speed precision spindles in the above-mentioned technical solution, the loading method comprising:

[0021] S1: Fix the spindle, install the moving magnet mechanism at the working end of the spindle and control the spindle to run;

[0022] S2: Control the extension and retraction of the two distance adjustment components to adjust the distance between the axial force moving magnet and the radial force moving magnet and the corresponding stationary magnet, so that the two force sensors reach the corresponding loading value;

[0023] S3: The locking distance adjustment component locks the distance between the corresponding fixed magnet and the corresponding axial force moving magnet and radial force moving magnet, thereby enabling the application of axial and radial forces to the spindle.

[0024] (III) Beneficial Effects

[0025] The beneficial effects of this invention are as follows: The non-contact force loading device for high-speed precision spindles of this invention adopts a completely non-contact magnetic loading method, completely eliminating friction and wear caused by mechanical contact. This not only ensures that the spindle can rotate freely at its true operating speed during testing without affecting its dynamic performance, but also prevents contact friction from affecting the high-speed rotating spindle. Since there is no need to apply force through high-speed airflow, and high-pressure airflow loading does not cause changes in spindle temperature, it helps maintain the thermal characteristics of the spindle under real operating conditions. Furthermore, all magnets can be permanent magnets, so electromagnetic heating will not cause the spindle to heat up, thus affecting the spindle test results. At the same time, this spindle loading device has a simple structure, low cost, high loading force accuracy, and good stability. Within the load range, load adjustment is convenient and operation is simple, which is conducive to achieving low-cost, high-reliability testing of high-speed precision spindle performance. Attached Figure Description

[0026] Figure 1 This is one of the structural schematic diagrams of the non-contact force loading device for high-speed precision spindles according to the present invention;

[0027] Figure 2 This is the second schematic diagram of the non-contact force loading device for high-speed precision spindles according to the present invention;

[0028] Figure 3 This is a schematic diagram of the structure of the moving magnet mechanism when the radial force moving magnet of the present invention is annular;

[0029] Figure 4This is a top view of the structure of the radial force magnet of the present invention when it is an annular shape;

[0030] Figure 5 This is a schematic diagram showing the change of radial loading force with the rotation angle of the main shaft when the radial force moving magnet of the present invention is annular;

[0031] Figure 6 This is a schematic diagram of the structure of the moving magnet mechanism when the radial force moving magnet of the present invention is a fan-shaped ring;

[0032] Figure 7 This is a top view of the radial force magnet of the present invention when it is a fan-shaped ring.

[0033] Figure 8 This is a schematic diagram showing the change of radial loading force with the rotation angle of the main shaft when the radial force moving magnet of the present invention is a fan-shaped ring.

[0034] Explanation of reference numerals in the attached figures

[0035] 1: Spindle;

[0036] 2: Moving magnet mechanism;

[0037] 21. Mounting base; 22. Axial force moving magnet; 23. Radial force moving magnet; 24. Isolation flange;

[0038] 3: Loading mechanism;

[0039] 31. Fixed magnet; 32. Force sensor; 33. Distance adjustment component. Detailed Implementation

[0040] To better explain and facilitate understanding of this invention, the following description is provided in conjunction with the appendix. Figures 1-8 The present invention will be described in detail through specific embodiments. In this document, directional terms such as "upper" and "lower" are used interchangeably with other directional terms. Figure 1 The orientation is used as a reference.

[0041] Example 1:

[0042] Reference Figures 1-8 An embodiment of the present invention provides a non-contact force loading device for a high-speed precision spindle, comprising:

[0043] The moving magnet mechanism 2 includes a mounting base 21 that can be detachably connected to the main shaft 1 at one end, an axial force moving magnet 22 that is fixedly connected to the other end of the mounting base 21, and a radial force moving magnet 23 that is fixedly connected to the radial outer edge of the mounting base 21, and all three are coaxial with the main shaft 1.

[0044] Both loading mechanisms 3 include a fixed magnet 31, a force sensor 32, and a distance adjustment component 33 connected in sequence. The distance adjustment component 33 is adapted to drive the fixed magnet 31 to slide along the length direction of the loading mechanism 3, and the force sensor 32 is adapted to detect the loading force of the fixed magnet 31.

[0045] The main shaft 1 can drive the moving magnet mechanism 2 to rotate axially; a loading mechanism 3 is coaxially arranged with the main shaft 1, and the corresponding fixed magnet 31 can axially approach or move away from the axial force moving magnet 22 to load the moving magnet mechanism 2 axially through magnetic force; another loading mechanism 3 is perpendicular to the axis of the main shaft 1, and the corresponding fixed magnet 31 can radially approach or move away from the radial force moving magnet 23 to load the moving magnet mechanism 2 radially through magnetic force; the corresponding fixed magnet 31 is kept separate from the corresponding axial force moving magnet 22 and radial force moving magnet 23.

[0046] The moving magnet mechanism 2 is detachably and fixedly connected to the spindle 1 and is coaxial with the spindle 1. By loading the axial force moving magnet 22 and the radial force moving magnet 23 through the two loading mechanisms 3 respectively, the spindle 1 can be indirectly loaded. This allows the spindle 1 to be simulated to wobble during actual machining. It can apply precise and controllable axial and radial forces to the spindle 1 without physical contact with it, thereby simulating the complex loads on the spindle 1 under actual working conditions. This provides a reliable testing method for evaluating the dynamic accuracy, stiffness and operational stability of the spindle 1.

[0047] This technical solution utilizes magnetic force to achieve non-contact loading of the spindle 1, thus avoiding any impact on the normal rotation of the spindle 1 due to contact friction, and preventing the spindle 1 from cooling down due to airflow. Furthermore, all magnets can be permanent magnets, preventing electromagnetic heating that could affect the detection accuracy of the spindle 1. This detection method is also relatively inexpensive, contributing to a reduction in the overall cost of detecting the spindle 1's accuracy.

[0048] Specifically, the device mainly includes a moving magnet mechanism 2 and two independent loading mechanisms 3. The moving magnet mechanism 2 is directly mounted on the main shaft 1 and maintains a coaxial relationship with the main shaft 1. This mechanism has a mounting base 21, one end of which is detachably fixedly connected to the end of the main shaft 1; an axial force moving magnet 22 is fixedly installed at the other end of the mounting base 21 to generate axial magnetic force; and a radial force moving magnet 23 is fixedly installed at the radial outer edge of the mounting base 21 to generate radial magnetic force. The entire moving magnet mechanism 2 rotates together with the main shaft 1.

[0049] Two loading mechanisms 3 are arranged orthogonally in space, respectively for applying magnetic force to the axial force moving magnet 22 and the radial force moving magnet 23. Each loading mechanism 3 includes a fixed magnet 31, a force sensor 32, and a distance adjustment component 33 connected sequentially along its length. The distance adjustment component 33 can drive the fixed magnet 31 to move precisely along the axis of the loading mechanism 3, thereby adjusting the air gap distance between the fixed magnet 31 and the corresponding moving magnet. The force sensor 32 monitors and provides feedback on the magnitude of the magnetic force on the fixed magnet 31 in real time. One loading mechanism 3 is arranged coaxially with the main shaft 1, with its fixed magnet 31 facing the axial force moving magnet 22, and can move closer or further away along the axis; the other loading mechanism 3 is arranged perpendicular to the axis of the main shaft 1, with its fixed magnet 31 facing the radial force moving magnet 23, and can move closer or further away along the radial direction. In all operating states, the fixed magnet 31 and the corresponding moving magnet always remain in a non-contact, separated state.

[0050] During operation, the gaps between the axial and radial stationary magnets 31 and their corresponding moving magnets can be independently adjusted by controlling the movement of the distance adjustment components 33 in the two loading mechanisms 3. Based on the specific relationship between the interaction force between the magnets and the size of the gap, precisely set axial and radial forces can be applied to a rotating spindle 1. Since the force transmission is achieved entirely through magnetic field coupling, any mechanical contact is avoided, and the moving magnet mechanism 2 can rotate freely with the spindle 1 without introducing frictional resistance or wear.

[0051] This technical solution employs a completely non-contact magnetic loading method, completely eliminating friction and wear caused by mechanical contact. This ensures that spindle 1 can rotate freely at its actual operating speed during testing without affecting its dynamic performance, while also avoiding surface damage or temperature rise that might occur with contact loading devices. Since no high-speed airflow is needed to apply force, forced convection is avoided, preventing temperature drops in spindle 1 and helping to maintain its thermal characteristics under real-world operating conditions. All magnets in the device can be permanent magnets, eliminating the need for energized coils. This fundamentally eliminates the additional thermal impact on the spindle 1 system caused by Joule heating generated during electromagnet operation, significantly improving the stability of the temperature field and the accuracy of test results. The entire device has a simple structure, requiring no complex lubrication, sealing, or cooling systems. Manufacturing and maintenance costs are significantly lower than traditional hydraulic or pneumatic loading systems and electromagnet-based loading solutions, reducing the overall cost of high-speed precision spindle comprehensive performance testing. This makes it suitable for widespread application in R&D, quality inspection, and production environments. This device can achieve independent, precise, and adjustable loading of axial and radial forces, and can flexibly simulate various actual machining load conditions, providing an efficient and reliable testing platform for the dynamic accuracy evaluation, vibration characteristic analysis, and reliability verification of spindle 1.

[0052] Furthermore, by adjusting the connection position of the mounting base 21 at the end of the spindle 1, the axial position of the axial force moving magnet 22 and the radial force moving magnet 23 relative to the spindle can be adjusted, thereby making the force position of the axial force moving magnet 22 and the radial force moving magnet 23 more closely match the actual machining conditions they simulate, thus improving the accuracy of the loading device.

[0053] Example 2:

[0054] Reference Figures 1-8 In addition to possessing all the technical solutions of the above embodiments, the embodiments of the present invention further possess the following technical solutions:

[0055] The axial force moving magnet 22 and the radial force moving magnet 23 are both opposite to the corresponding fixed magnet 31, either with the same pole or opposite pole, preferably with the same pole. Furthermore, the fixed magnet 31 on the loading mechanism 3 can be configured to change the orientation of its magnetic poles, such as by detachably connecting it to the force sensor 32, to improve flexibility.

[0056] In this embodiment, the axial force moving magnet 22 and the corresponding axial fixed magnet 31, as well as the radial force moving magnet 23 and the corresponding radial fixed magnet 31, transmit force through the interaction of magnetic fields. They can be arranged with like poles facing each other or opposite poles facing each other to achieve the loading of repulsive or attractive forces.

[0057] Preferably, a like-pole-opposite arrangement is adopted. In this configuration, when the moving magnet rotates at high speed with the main shaft 1, the repulsive magnetic fields of like poles can form a stable repulsive force field between the stationary and moving magnets. This loading mode, dominated by repulsion, not only effectively transmits the required axial or radial load but also significantly reduces the risk of contact between the moving and stationary magnets 31 due to accidental magnetic attraction, thereby improving the safety and controllability of the entire loading process. Simultaneously, utilizing the repulsive property of like poles of permanent magnets enhances the predictability and repeatability of the loading force.

[0058] Example 3:

[0059] Reference Figures 1-8 In addition to possessing all the technical solutions of the above embodiments, the embodiments of the present invention further possess the following technical solutions:

[0060] Based on Embodiment 1, the two fixed magnets 31 can be replaced with electromagnets. Electromagnets can change their polarity so that the fixed magnets 31 can be opposite to the corresponding axial force moving magnets 22 and radial force moving magnets 23 with the same pole, or opposite to the corresponding axial force moving magnets 22 and radial force moving magnets 23 with opposite poles. This allows the loading device to flexibly provide thrust or pull force, improving the flexibility of the loading device.

[0061] In this embodiment, the magnetic polarity of the electromagnet can be actively changed by controlling the excitation current of the electromagnet. This allows each electromagnet's fixed magnet 31 to be either aligned with the corresponding permanent magnet moving magnet to generate a repulsive force, or to be aligned with opposite poles to generate an attractive force. Based on this characteristic, the loading device can flexibly and quickly switch the direction of the axial and radial forces applied to the main shaft 1 without changing the mechanical structure or relative positions.

[0062] This technical solution significantly enhances the testing flexibility and functional coverage of the device. During the actual operation of spindle 1, its stress state is often complex and variable; for example, it may experience alternating axial loads during milling. Through controllable switching of the electromagnet's polarity, this device can dynamically simulate this bidirectional pushing and pulling alternating force condition, thereby more realistically and comprehensively evaluating the spindle 1's accuracy retention, stiffness characteristics, and vibration response under complex dynamic loads. This technical solution also retains the advantages of permanent magnets and moving magnets rotating at high speeds with spindle 1 without generating heat or requiring power, while concentrating the controllable components on the stationary electromagnet, ensuring the system's reliability and accuracy. The flexible loading modes provided by the electromagnet, combined with the aforementioned advantages of non-contact, frictionless, and low thermal impact, make this device a more versatile and flexible high-speed precision spindle dynamic performance testing platform.

[0063] Example 4:

[0064] Reference Figures 1-8 In addition to possessing all the technical solutions of the above embodiments, the embodiments of the present invention further possess the following technical solutions:

[0065] The radial force moving magnet 23 is a ring magnet to simulate the machining condition where the spindle 1 bears a continuous radial force, such as forming a force-bearing body to simulate the grinding condition of the spindle 1. Since the radial force generated by the ring magnet when it cooperates with the fixed magnet 31 is continuous, and the radial force on the grinding head during grinding is also continuous, a more accurate simulation of the grinding condition can be achieved, improving the detection accuracy of the spindle 1 offset when using this loading device.

[0066] In this embodiment, the annular permanent magnet has a uniform and continuous magnetic field distribution in the circumferential direction. When the axial force moving magnet 22 interacts with the corresponding fixed magnet 31, a continuous and stable radial force field can be generated throughout the entire circumference. The characteristics of the force are highly consistent with the continuous and uniform radial load characteristics borne by the grinding head under the processing conditions such as grinding and polishing of the spindle 1. It can more realistically and accurately reproduce the stress state in actual processing, and improve the realism of the device in simulating specific process conditions and the accuracy of the test results.

[0067] By achieving continuous and uniform radial loading force, this device can more effectively stimulate the true dynamic response of the spindle 1 under corresponding working conditions, making the detection data on the spindle 1's offset, stiffness, and operational stability more reliable and directly improving detection accuracy. Simultaneously, the simple structure of the annular magnet facilitates coaxial assembly with the spindle 1 mounting base 21, ensuring rotational balance and further reducing test interference introduced by unbalanced forces. Furthermore, this technical solution, together with the aforementioned solutions, enables the device to not only perform general-purpose tests but also provide highly specialized and accurate simulation testing capabilities for processing scenarios with typical continuous stress characteristics, such as grinding.

[0068] Example 5:

[0069] Reference Figures 1-8 In addition to possessing all the technical solutions of the above embodiments, the embodiments of the present invention further possess the following technical solutions:

[0070] The radial force moving magnet 23 is a fan-shaped annular magnet, and there are multiple ones evenly distributed around the outer edge of the mounting base 21 to simulate the machining condition of the spindle 1 bearing intermittent radial force, such as forming a force-bearing body that simulates the milling condition of the spindle 1.

[0071] In this embodiment, the circumferentially uniformly arranged fan-shaped annular magnets cause the radial magnetic field to exhibit a periodic distribution in the circumferential direction. When the radial force moving magnet 23 rotates with the spindle 1, the interaction force generated between it and the corresponding stationary magnet 31 also exhibits periodic fluctuation characteristics. This mechanical characteristic is highly similar to the periodic and intermittent radial impact loads experienced by the spindle 1 during milling, enabling it to more realistically reproduce the dynamic loads experienced by the spindle 1 during milling. Therefore, it is specifically used to evaluate the dynamic response, vibration suppression capability, and accuracy retention of the spindle 1 system under periodic impact loads.

[0072] Users can flexibly select or replace different radial force magnets 23 according to specific testing purposes, thereby achieving accurate and efficient evaluation of the spindle 1 performance under different process conditions on a single device, greatly improving the practical value of the equipment and the pertinence of testing and analysis.

[0073] Example 6:

[0074] Reference Figures 1-8 In addition to possessing all the technical solutions of the above embodiments, the embodiments of the present invention further possess the following technical solutions:

[0075] The number of fan-shaped annular magnets is n, where n is an integer and 2≤n≤6, and they are evenly distributed on the radial outer edge of the mounting base 21, thereby enabling the fan-shaped annular magnets to meet the requirements of simulating the force conditions of a milling cutter with 2-6 cutting edges.

[0076] Specifically, a connecting sleeve can be additionally fixedly connected to the mounting base 21, and a corresponding number of sector-shaped magnets can be directly fixedly connected to the connecting sleeve. By replacing the connecting sleeve with different numbers of sector-shaped magnets, the operating conditions of simulating different numbers of cutting edge end mills can be met.

[0077] Example 7:

[0078] Reference Figures 1-8 In addition to possessing all the technical solutions of the above embodiments, the embodiments of the present invention further possess the following technical solutions:

[0079] The fan-shaped annular magnets are detachably connected to the mounting base 21, allowing for the simulation of machining tools with different numbers of cutting edges using varying combinations of fan-shaped annular magnets, such as milling cutters with different numbers of cutting edges. Specifically, the mounting base 21 has six grooves evenly distributed around its circumference. For 2, 3, and 6 fan-shaped annular magnets, the number of magnets can be increased or decreased to ensure that the required number of magnets is met while maintaining their evenly distributed circumferential shape.

[0080] For applications requiring 4 or 5 sector ring magnets, the entire mounting base 21 can be replaced, or a different connecting sleeve can be replaced as described in the above embodiment, to meet the application requirements of 5 sector ring magnets.

[0081] The connection between the fan-shaped annular magnet and the mounting base 21 adopts a detachable modular design. Users can easily replace or combine different numbers of fan-shaped annular magnets according to the number of milling cutter cutting edges to be simulated, thereby quickly and accurately constructing the corresponding dynamic load model. Specifically, six axial grooves are uniformly machined circumferentially on the radial outer edge of the mounting base 21. When simulating the working conditions of 2-tooth, 3-tooth, or 6-tooth milling cutters, simply install the corresponding number of fan-shaped annular magnets at the corresponding positions to naturally meet the requirement of circumferential uniform distribution, without replacing any basic components, achieving rapid replacement and efficient configuration.

[0082] For cases where simulating a 4- or 5-tooth end mill cannot be achieved directly using the aforementioned six-slot base, alternative mounting base 21 with pre-defined evenly spaced slots can be used, or a dedicated transition connection kit can be employed. This connection kit can be directly mounted on a standard six-slot base and features 4 or 5 circumferentially evenly distributed mounting positions, thus securely supporting the corresponding number of fan-shaped magnets. Both solutions ensure that the magnet assembly maintains precise circumferential distribution under the new configuration, meeting the requirements for generating specific frequency and uniform dynamic loads.

[0083] This technical solution enables users to accurately respond to the rapid verification needs of spindle 1's ability to adapt to different process conditions in the R&D and quality inspection stages on the same loading device with low switching costs and time, greatly improving the depth and efficiency of testing work.

[0084] Example 8:

[0085] Reference Figures 1-8 In addition to possessing all the technical solutions of the above embodiments, the embodiments of the present invention further possess the following technical solutions:

[0086] The mounting base 21 between the axial force magnet 22 and the radial force magnet 23 is made of a non-magnetic material, thereby avoiding mutual interference between the magnetic forces of the axial force magnet 22 and the radial force magnet 23.

[0087] The non-magnetic material can be aluminum alloy or high-strength engineering plastic, which can block the direct coupling path of magnetic lines of force between the axial force moving magnet 22 and the radial force moving magnet 23 to a certain extent, thereby minimizing unnecessary mutual interference between the magnetic fields in the two directions and improving the accuracy and reliability of the spindle 1 when using the loading device to detect its accuracy.

[0088] Example 9:

[0089] Reference Figures 1-8 In addition to possessing all the technical solutions of the above embodiments, the embodiments of the present invention further possess the following technical solutions:

[0090] The moving magnet mechanism 2 also includes an isolation flange 24 fixedly connected to the mounting base 21 and located between the axial force moving magnet 22 and the radial force moving magnet 23. The isolation flange 24 is made of non-magnetic material.

[0091] By introducing the isolation flange 24 as a physical isolation barrier, the active regions of the two magnetic fields are structurally separated, which further effectively suppresses the weak magnetic coupling path that may be formed through the steel structure of the mounting base 21, and ensures the independence of the magnetic lines of force in the two directions.

[0092] Specifically, the mounting base 21 includes an upper rod and a cylinder connecting the lower end of the rod. An isolation flange 24 is fixedly connected to the lower side of the cylinder, and the outer wall of the cylinder is used to connect the radial force magnet 23.

[0093] Example 10:

[0094] Figures 1-8 In addition to providing a non-contact force loading method, embodiments of the present invention apply to the non-contact force loading device for high-speed precision spindles in any of the above embodiments. The loading method includes:

[0095] S1: Fix the main spindle 1, install the moving magnet mechanism 2 on the working end of the main spindle 1 and control the operation of the main spindle 1;

[0096] S2: Control the extension and retraction of the two distance adjustment components 33 to adjust the distance between the axial force moving magnet 22 and the radial force moving magnet 23 and the corresponding stationary magnet 31, so that the two force sensors 32 reach the corresponding loading value;

[0097] S3: The locking distance adjustment component 33 locks the distance between the corresponding fixed magnet 31 and the corresponding axial force moving magnet 22 and radial force moving magnet 23, thereby realizing the application of axial force and radial force to the spindle 1;

[0098] Furthermore, before S1, it may also include:

[0099] S0: Determine the simulated machining conditions;

[0100] S0.1: Based on the processing condition being a grinding condition, the radial force moving magnet 23 is made into a circular ring magnet;

[0101] S0.2: Based on the milling condition, the radial force moving magnet 23 is made into a fan-shaped annular magnet corresponding to the number of milling cutter cutting edges.

[0102] In this embodiment, the method aims to apply precise and controllable axial and radial loads to the high-speed rotating spindle 1 using non-contact magnetic force, thereby simulating its actual working stress state, in order to detect and evaluate the dynamic accuracy, stiffness and stability of the spindle 1.

[0103] First, the machining conditions to be simulated are determined based on the target testing requirements. If simulating conditions with continuous radial load characteristics, such as grinding or milling, a ring magnet is selected as the radial force magnet 23. If simulating conditions with periodic intermittent load characteristics, such as milling, a corresponding number of circumferentially distributed fan-shaped ring magnet assemblies are selected as the radial force magnet 23, based on the number of cutting edges of the milling cutter used. The initial configuration steps ensure that the load spectrum characteristics match the actual working conditions.

[0104] Special note: S0-S0.2 are optional steps. Even without matching the machining conditions, the actual machining situation of spindle 1 can be roughly simulated.

[0105] After completing the working condition configuration, start the spindle 1 to reach the preset operating speed. While the spindle 1 is running stably, operate the axial and radial distance adjustment components 33 respectively to drive the corresponding stationary magnet 31 closer to or further away from the moving magnet rotating with the spindle 1. By monitoring the feedback data from the force sensor 32 in real time, precisely adjust the air gap distance between the stationary magnet 31 and the moving magnet until the applied axial and radial forces reach the preset loading values. Then, lock each distance adjustment component 33 to fix the spatial position of the stationary magnet 31, thereby maintaining a constant magnetic loading state during the test. Subsequently, under continuous combined load, record the dynamic response data such as the axial and radial offset of the spindle 1 through an external displacement detection system.

[0106] This technical solution utilizes steps S0-S0.2 to achieve simulation before loading. Through flexible selection and configuration of magnets in the early stage, it can accurately simulate the force characteristics in various typical machining processes, such as continuous grinding and intermittent milling, significantly enhancing the relevance and realism of the test.

[0107] The operation of spindle 1 before force loading ensures that all loading actions are completed under the dynamic rotation condition of spindle 1, completely avoiding the interference that may be introduced by static loading restart, and making the test data more reflective of the real-time dynamic performance of spindle 1.

[0108] By adjusting and locking the process, stable and repeatable static or quasi-static loads can be applied under non-contact conditions, providing a reliable means to evaluate the static stiffness and long-term operational stability of spindle 1.

[0109] Overall, this method fully leverages the advantages of modularity, non-contact operation, and multi-dimensional independent controllability of the device, forming a standardized, efficient, and widely applicable high-speed spindle performance testing process, which greatly improves testing accuracy, repeatability, and engineering practical value.

[0110] Specifically, the displacement adjustment accuracy of the distance adjustment component 33 should be better than 0.05 mm, and it should have a position self-locking function, similar to an electric telescopic rod driven by a servo motor. The force sensor 32 is a pressure sensor with a measurement accuracy better than 0.2 N. By limiting the displacement adjustment accuracy of the distance adjustment component 33 and the measurement accuracy of the force sensor 32, the accuracy and reliability of the loading device can be guaranteed. Furthermore, by limiting the displacement adjustment accuracy of the distance adjustment component 33 to better than 0.05 mm and the measurement accuracy of the force sensor 32 to better than 0.2 N, the accuracy and reliability of the loading device can be further improved.

[0111] It can be understood that, except for conflicting parts, the above embodiments 1-10 can be freely combined to form other embodiments of the present invention.

[0112] In the description of this invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0113] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0114] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that they are in indirect contact through an intermediate medium. Furthermore, "above," "over," or "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," or "beneath" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0115] The term "comprising" or any other similar term is intended to cover non-exclusive inclusion, such that a process, article, or apparatus / device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to those processes, articles, or apparatus / devices.

[0116] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A non-contact force loading device for a high-speed precision spindle, characterized in that, include: The moving magnet mechanism (2) includes a mounting base (21) that can be detachably connected to the main shaft (1) at one end, an axial force moving magnet (22) fixedly connected to the other end of the mounting base (21), and a radial force moving magnet (23) fixedly connected to the radial outer edge of the mounting base (21), and all three are coaxial with the main shaft (1). Both loading mechanisms (3) include a fixed magnet (31), a force sensor (32) and a distance adjustment component (33) connected in sequence. The distance adjustment component (33) is adapted to drive the fixed magnet (31) to slide along the length direction of the loading mechanism (3), and the force sensor (32) is adapted to detect the loading force of the fixed magnet (31). The main shaft (1) can drive the moving magnet mechanism (2) to rotate axially; a loading mechanism (3) is coaxially arranged with the main shaft (1), and the corresponding fixed magnet (31) can move axially closer to or away from the axial force moving magnet (22) so as to load the moving magnet mechanism (2) axially by magnetic force; another loading mechanism (3) is perpendicular to the axis of the main shaft (1), and the corresponding fixed magnet (31) can move radially closer to or away from the radial force moving magnet (23) so as to load the moving magnet mechanism (2) radially by magnetic force; the corresponding fixed magnet (31) is kept separate from the corresponding axial force moving magnet (22) and radial force moving magnet (23).

2. The non-contact force loading device for a high-speed precision spindle as claimed in claim 1, characterized in that, The axial force moving magnet (22) and the radial force moving magnet (23) are opposite to the corresponding fixed magnet (31) with the same pole or opposite pole.

3. The non-contact force loading device for a high-speed precision spindle as claimed in claim 2, characterized in that, The radial force moving magnet (23) is a circular ring magnet to simulate the machining condition in which the spindle (1) bears continuous radial force.

4. The non-contact force loading device for a high-speed precision spindle as claimed in claim 2, characterized in that, The radial force moving magnet (23) is a fan-shaped annular magnet, and there are multiple ones evenly distributed around the outer edge of the mounting base (21) to simulate the machining condition of the spindle (1) bearing intermittent radial force.

5. The non-contact force loading device for a high-speed precision spindle as claimed in claim 4, characterized in that, The number of fan-shaped magnets is n, where n is an integer and 2≤n≤6, and they are evenly distributed on the radial outer edge of the mounting base (21).

6. The non-contact force loading device for a high-speed precision spindle as claimed in claim 5, characterized in that, The fan-shaped magnet is detachably connected to the mounting base (21) to simulate machining tools with different numbers of cutting edges by using fan-shaped magnets in different combinations.

7. The non-contact force loading device for a high-speed precision spindle as claimed in claim 1, characterized in that, The solid between the mounting base (21) and the axial force magnet (22) and the radial force magnet (23) is made of non-magnetic material.

8. The non-contact force loading device for a high-speed precision spindle as claimed in claim 1, characterized in that, The moving magnet mechanism (2) also includes an isolation flange (24) fixedly connected to the mounting base (21) and located between the axial force moving magnet (22) and the radial force moving magnet (23), the isolation flange (24) being made of non-magnetic material.

9. A non-contact force loading method, characterized in that, The non-contact force loading device for a high-speed precision spindle, applicable to any one of claims 1-8, comprises the following loading method: S1: Fix the main shaft (1), install the moving magnet mechanism (2) on the working end of the main shaft (1) and control the main shaft (1) to run; S2: Control the extension and retraction of the two distance adjustment parts (33) to adjust the distance between the axial force moving magnet (22) and the radial force moving magnet (23) and the corresponding fixed magnet (31) so that the two force sensors (32) reach the corresponding loading value; S3: Locking distance adjustment component (33) locks the distance between the corresponding fixed magnet (31) and the corresponding axial force moving magnet (22) and radial force moving magnet (23), thereby realizing the loading of axial force and radial force on the spindle (1).

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