A stability testing device for a spherical support method

Abstract

This invention discloses a stability testing device for a sphere support method, comprising: a vibration direction measuring mechanism, including two sets of mutually perpendicular first capacitor plates, two second capacitor plates, and a capacitive displacement sensing system. The four first capacitor plates are suspended around the sphere to measure the positional changes of the tested unit in two vertical directions under vibration. The two second capacitor plates are positioned opposite the two first capacitor plates in the vertical direction to measure the positional changes of the first capacitor plates in two vertical directions under vibration. A processing mechanism is used to perform differential processing on the positional changes to obtain the positional change of the sphere caused by vibration. This result is then combined with the vibration signal measured by the vibration signal monitoring mechanism to detect the stability of the sphere. This invention enables the detection of sphere stability in G-test experiments, providing a basis for further optimization of the precision sphere manufacturing process.

Description

Technical Field

[0001] This invention belongs to the field of precision measurement technology, and more specifically, relates to a stability testing device for a sphere support method. Background Technology

[0002] With the rapid development of modern machinery and aerospace industries, the performance and precision requirements for fundamental components are becoming increasingly stringent. The standard sphere is a crucial element in roundness meters, gyroscopes, coordinate measuring machines, imaging systems, and precision measurement, often serving as a reference for precision measurements. Clearly, the standard sphere holds a vital position in both modern industrial and precision engineering fields. In G-force (gravitational acceleration) measurements, the standard sphere is inevitably affected by external factors such as ground vibrations and earthquakes. Experiments have shown that the positioning support of the standard sphere contributes 3 ppm of error in G-force measurements, primarily due to the positional changes caused by system vibrations.

[0003] Therefore, there is an urgent need for a device that can detect the stability of a sphere in a G-test experiment. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a stability testing device for a sphere support method, which can detect the stability of the sphere in the G-test experiment, and provide a basis for further optimization of the precision sphere manufacturing process.

[0005] To achieve the above objectives, the present invention provides a stability testing device for a sphere support method, used for stability testing of a sphere in a G-test experiment, comprising:

[0006] The sphere support mechanism includes a microcrystalline disk and a support ring disposed on the microcrystalline disk. The sphere to be tested is placed on the support ring. The sphere to be tested, the microcrystalline disk, and the support ring constitute the detection unit.

[0007] The vibration signal monitoring mechanism includes a vibration table and a micro-vibration meter set on the microcrystalline disk. The vibration table is used to apply a vibration signal to the microcrystalline disk, and the micro-vibration meter is used to monitor the vibration signal in real time.

[0008] The vibration direction measuring mechanism includes two sets of mutually perpendicular first capacitor plates, two second capacitor plates, and a capacitive displacement sensing system. The four first capacitor plates are suspended around the perimeter of the tested sphere at the same height as the sphere, and are used in conjunction with the capacitive displacement sensing system to measure the positional changes of the tested unit in two vertical directions under vibration. The two second capacitor plates are mounted on a microcrystalline disk, corresponding to the two first capacitor plates positioned vertically, and are also used in conjunction with the capacitive displacement sensing system to measure the positional changes of the first capacitor plates in two vertical directions under vibration.

[0009] The processing mechanism is used to acquire the positional changes of the tested unit under vibration in two vertical directions as measured by the vibration direction measuring mechanism, and the positional changes of the first capacitor plate under vibration in two vertical directions; then, the positional changes of the two are differentially processed to obtain the positional change of the tested sphere caused by vibration; then, based on the positional change of the tested sphere caused by vibration and the vibration signal measured by the vibration signal monitoring mechanism, the displacement change of the tested sphere is calculated, thereby realizing the detection of the stability of the tested sphere.

[0010] The stability detection device for the sphere support method provided by the present invention combines a capacitive displacement sensing system with a vibration signal monitoring mechanism, which can realize the stability detection of the sphere support method under vibration interference. Its advantages are mainly reflected in: (1) By connecting the two-stage capacitor plates with the capacitive displacement sensing system to make differential, the high-sensitivity measurement of the sphere position change in two directions can be realized; (2) By suspending the two sets of first capacitor plates around the sphere under test, the two sets of first capacitor plates can be kept unaffected by vibration when a vibration signal is applied; (3) By using a vibration table to apply a vibration signal to the microcrystalline disk and combining it with a micro-vibration meter, the vibration signal can be monitored in real time.

[0011] In one embodiment, the capacitive displacement sensing system includes four capacitive displacement sensing circuits, wherein two capacitive displacement sensing circuits are connected to two sets of first capacitor plates respectively, and the other two capacitive displacement sensing circuits are connected to two sets of first capacitor plates and second capacitor plates that are arranged opposite each other.

[0012] In one embodiment, the coefficient calibration methods for the two capacitive displacement sensing circuits are as follows: Before assembling the device, a support ring is mounted on a translation stage and placed on a microcrystalline disk; then, the sphere to be tested is placed on the support ring, and by adjusting the micrometer cylinder on the translation stage, the sphere to be tested is moved 1 to 10 μm along the direction of the connection line between the first capacitor plate and the capacitive displacement sensing circuit, and then stops until the capacitor plates are relatively balanced, thereby obtaining the relationship between the voltage output by the capacitive displacement sensing circuit and the moving distance; then, the least squares method is used to fit it to obtain the calibration coefficients of the capacitive displacement sensing circuit.

[0013] In one embodiment, the calibration methods for the coefficients of the other two capacitive displacement sensing circuits are as follows: Before assembling the device, a translation stage is installed under the suspended first capacitor plate; then, by adjusting the micrometer drum on the translation stage, the first capacitor plate connected to the capacitive displacement sensing circuit is moved 1 to 10 μm along the line connecting the second capacitor plate directly opposite it, and then stops until the capacitor plates are relatively balanced, thereby obtaining the relationship between the voltage output of the capacitive displacement sensing circuit and the moving distance; then, the least squares method is used to fit it to obtain the calibration coefficients of the capacitive displacement sensing system.

[0014] In one embodiment, four first capacitor plates are suspended around the sphere under test by capacitor plate supports. The base of the capacitor plate supports is fixed on two vibration isolation platforms, which are located on opposite sides of the microcrystalline disk.

[0015] In one embodiment, three Invar support columns are bonded to the support ring, the upper end of each Invar support column having a 45° cut surface that contacts the sphere being tested at three specific points.

[0016] In one embodiment, the microdisc is placed on a support platform. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the stability testing device for a sphere support method provided in an embodiment of the present invention;

[0018] Figure 2 This is a diagram showing the positional relationship between capacitor plates A and B according to an embodiment of the present invention;

[0019] Figure 3 This is a schematic diagram of a variable-pitch capacitive sensing principle provided in an embodiment of the present invention;

[0020] Figure 4 This is a schematic diagram of a sphere support method provided in an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0022] To improve the quality of the standard ball during use and reduce experimental errors, this invention applies a vibration signal to the ball support plate and monitors the ball's position changes in real time. This allows for timely understanding of the standard ball's state, analysis of the ball's position stability under vibration interference, and provides a basis for further optimization of the precision ball's manufacturing process.

[0023] Figure 1 This is a schematic diagram of the stability testing device for a sphere support method provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the stability testing device mainly includes a sphere support mechanism, a vibration signal monitoring mechanism, a vibration direction measurement mechanism, and a processing mechanism.

[0024] In this embodiment, the sphere support mechanism includes a microcrystalline disk 30 and a support ring 20 disposed on the microcrystalline disk 30. The sphere to be tested 10 is placed on the support ring 20. The sphere to be tested 10, the microcrystalline disk 30, and the support ring 20 constitute the unit to be tested. Preferably, the microcrystalline disk 30 can be a microcrystalline glass disk. The microcrystalline glass disk is placed on the support platform 60, which can reduce the impact of ground vibration and other factors on the unit to be monitored.

[0025] The vibration signal monitoring mechanism includes a vibration table 40 and a micro-vibration meter 50 installed on the microcrystalline disk 30. The vibration table 40 is used to apply a vibration signal to the microcrystalline disk 30, and the micro-vibration meter 50 is used to monitor the vibration signal in real time.

[0026] The vibration direction measurement mechanism includes four capacitor plates A, two capacitor plates B, and a capacitive displacement sensing system. (See also...) Figure 2 Four capacitor plates A are suspended around the tested sphere 10, forming two sets of mutually perpendicular capacitor plate pairs 72a and 72b. This ensures that the capacitor plates A are at the same height as the tested sphere 10, so that the capacitor plate pairs 72a and 72b are unaffected by vibration when a vibration signal is applied to the microcrystalline disk 30. Two capacitor plates B are disposed on the microcrystalline disk 30, and are positioned opposite the two capacitor plates A in the vertical direction, forming two sets of opposite capacitor plate pairs 74a and 74b.

[0027] The capacitive displacement sensing system can be composed of four capacitive displacement sensing circuits. These four circuits are electrically connected to capacitor plate pairs 72a and 72b and capacitor plate pairs 74a and 74b, respectively, to monitor the positional changes of the monitored unit as a whole in the vertical directions under vibration, and to monitor the positional changes of capacitor plate A in the vertical directions under vibration. Specifically, the capacitive displacement sensing circuit provided in this embodiment can adopt a commonly used capacitive displacement sensing circuit architecture in the art, namely, an architecture composed of a high-voltage amplifier, a frequency multiplier, a filter, and an analog-to-digital converter.

[0028] Specifically, the capacitive displacement sensing circuit provided in this embodiment, in conjunction with capacitor plates 72a and 72b, works on the principle of monitoring the positional changes of the monitored unit as a whole in the vertical directions under vibration as follows:

[0029] The capacitor plates 72a and 72b employ two sets of mutually perpendicular differential structures, with each capacitor plate pair used for monitoring in one direction. When the two capacitor plates A in a capacitor plate pair approach each other, they generate capacitances C1 and C2 relative to the sphere. As the position of the sphere changes, one capacitance increases and the other decreases, altering the difference between the two capacitances (C1-C2). This, in turn, affects the output voltage V of the capacitor displacement sensing circuit. d Change. Within a small range of motion, the circuit output V d The displacement Δd between the two capacitor plates A and the distance they approach is linearly related, i.e.: V d =α△d, where α is a linear proportionality coefficient, which can be obtained by coefficient calibration of the capacitive displacement sensing circuit before device assembly. Therefore, by using the capacitive displacement sensing circuit in conjunction with capacitor plates 72a and 72b, the positional changes of the monitored unit in two vertical directions can be obtained.

[0030] The capacitive displacement sensing circuit provided in this embodiment, in conjunction with capacitor plates 74a and 74b, monitors the positional changes of capacitor plate A in two vertical directions under vibration. The working principle is as follows:

[0031] The capacitor plates 74a and 74b employ two sets of mutually perpendicular variable-pitch structures, with each capacitor plate pair used for monitoring in one direction. For example... Figure 3 As shown, the change in capacitance ΔC in one direction varies with the change in spacing Δd as follows: Where ε is the dielectric constant, S is the area of ​​capacitor plates A and B facing each other, and d0 is the equilibrium spacing. This device uses a variable spacing structure to realize the positional change of capacitor plate A due to vibration in both perpendicular directions. When capacitor plate A senses vibration, it undergoes a displacement change Δd, generating a capacitance difference ΔC with its facing capacitor plate B, resulting in an output voltage V of the capacitor displacement sensing circuit. d The change occurs. Within a small range of movement, the circuit output V d It has a linear relationship with the displacement Δd, that is: V d =β△d, where β is the linear proportionality coefficient, which can be obtained through the coefficient calibration of the capacitive displacement sensing circuit. Therefore, by using the capacitive displacement sensing circuit in conjunction with capacitor plates 74a and 74b, the positional changes of capacitor plate A in the two vertical directions can be obtained.

[0032] The processing mechanism can use a DSP or microcontroller control circuit to execute the following process: Step 1, acquire the positional changes of the tested unit under vibration in two vertical directions and the positional changes of capacitor plate A under vibration in two vertical directions, as measured by the vibration direction measuring mechanism; Step 2, perform differential processing on the positional changes of the two to obtain the positional changes of the tested sphere caused by vibration; Step 3, calculate the displacement change of the tested sphere based on the positional changes of the tested sphere caused by vibration and the magnitude of the vibration signal measured by the vibration signal monitoring mechanism, thereby realizing the detection of the stability of the tested sphere.

[0033] The stability detection device for the sphere support method provided in this embodiment combines a capacitive displacement sensing system with a vibration signal monitoring mechanism, which can realize the stability detection of the sphere support method under vibration interference. Its advantages are mainly reflected in: (1) By connecting the two-stage capacitor plates with the capacitive displacement sensing system to make differential, the high-sensitivity measurement of the sphere position change in two directions can be realized; (2) By suspending the two sets of first capacitor plates around the sphere under test, the two sets of first capacitor plates can be kept unaffected by vibration when a vibration signal is applied; (3) By using a vibration table to apply a vibration signal to the microcrystalline disk and combining it with a micro-vibration meter, the vibration signal can be monitored in real time.

[0034] In one embodiment, the calibration method for the coefficients of the two capacitive displacement sensing circuits connected to the capacitor plates 72a and 72b respectively can be as follows: Before assembling the device, a support ring is mounted on a translation stage and placed on a microcrystalline disk; then, the ball to be tested is placed on the support ring, and by adjusting the micrometer cylinder on the translation stage, the ball to be tested is moved 1 to 10 μm, preferably 5 μm, along the direction of the connection line between the capacitor plates connected to the capacitive displacement sensing circuit, and then remains until the capacitor plates are relatively balanced, about 200s; thereby obtaining the relationship between the voltage output of the capacitive displacement sensing circuit and the moving distance; then, the least squares method is used to fit it to obtain the calibration coefficients of the capacitive displacement sensing circuit.

[0035] The calibration method for the coefficients of the two capacitor displacement sensing circuits connected to capacitor plates 74a and 74b respectively can be as follows: Before assembling the device, install the translation stage under the suspended capacitor plate A; then, by adjusting the micrometer drum on the translation stage, move capacitor plate A, which is connected to the capacitor displacement sensing circuit, along the line connecting capacitor plate B, which is in the opposite position, by 1 to 10 μm, preferably 5 μm, and then stop until the capacitor plates are relatively balanced, thereby obtaining the relationship between the voltage output of the capacitor displacement sensing circuit and the moving distance; then, perform least squares fitting to obtain the calibration coefficients of the capacitor displacement sensing circuit.

[0036] In one embodiment, such as Figure 1As shown, four capacitor plates A can be suspended around the sphere under test via capacitor plate bracket 80 and small plates, forming two sets of mutually perpendicular differential capacitor plates. The base of the capacitor plate bracket 80 is fixed to two vibration isolation tables 90, which are positioned on opposite sides of the microcrystalline disk 30. This ensures that the sphere and capacitor plates A are at the same height while preventing the capacitive displacement sensing system from being affected when vibration signals are applied by the vibration table 40.

[0037] In one embodiment, such as Figure 4 As shown, three Invar support columns can be adhered to the support ring. Invar has a very low coefficient of thermal expansion, approximately 1.6 x 10⁻⁶ / ℃, which effectively reduces the impact of temperature fluctuations on the sphere's position. The upper end of each Invar support column is a 45° cut surface. After grinding and polishing, its surface flatness is better than λ / 6, where λ is the wavelength of the helium-neon laser used in the interferometer employed in the G-measurement experiment (632.8 nm). The three Invar support columns are adhered to the support ring, with the sphere contacting the cut surface through three specific points. The sphere support mechanism provided in this embodiment employs a three-point support method, which effectively improves the stability of the sphere support.

[0038] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A stability testing device for a sphere support method, used for stability testing of a sphere in a G-test experiment, characterized in that, The device comprises: a ball supporting mechanism, which comprises a microcrystal disc and a supporting ring arranged on the microcrystal disc, and a measured ball is arranged on the supporting ring, and the measured ball, the microcrystal disc and the supporting ring constitute a detected unit; a vibration signal monitoring mechanism, which comprises a vibration table arranged on the microcrystal disc and a microseismograph, the vibration table is used for applying a vibration signal to the microcrystal disc, and the microseismograph is used for monitoring the vibration signal in real time; a vibration direction measuring mechanism, which comprises two groups of first capacitive plate pairs arranged perpendicularly to each other, two second capacitive plates and a capacitive displacement sensing system, wherein four first capacitive plate pairs are arranged in suspension around the measured ball and are consistent with the height of the measured ball, are used for cooperating with the capacitive displacement sensing system and measuring the position change of the detected unit in two perpendicular directions under the influence of vibration; and the two second capacitive plates are arranged on the microcrystal disc and are arranged opposite to the two first capacitive plates arranged in the perpendicular direction, are used for cooperating with the capacitive displacement sensing system and measuring the position change of the first capacitive plate in two perpendicular directions under the influence of vibration; a processing mechanism, which is used for acquiring the position change of the detected unit in two perpendicular directions under the influence of vibration and the position change of the first capacitive plate in two perpendicular directions under the influence of vibration measured by the vibration direction measuring mechanism; then, the position changes are differentially processed to obtain the position change of the measured ball caused by the influence of vibration; and then, according to the position change of the measured ball caused by the influence of vibration and the vibration signal measured by the vibration signal monitoring mechanism, the displacement change of the measured ball is calculated, so that the detection of the stability of the measured ball is realized.

2. The ball support type stability detection device according to claim 1, characterized by The capacitive displacement sensing system comprises four capacitive displacement sensing circuits, wherein two capacitive displacement sensing circuits are connected with the two groups of first capacitive plate pairs, and the other two capacitive displacement sensing circuits are connected with the two groups of first capacitive plates and second capacitive plates arranged opposite to each other.

3. The ball support type stability detection device according to claim 2, characterized by The calibration method of the two capacitive displacement sensing circuits is as follows: before assembling the device, the supporting ring is installed on the translation table and is arranged on the microcrystal disc; then, the measured ball is arranged on the supporting ring, the micrometer on the translation table is adjusted, the measured ball is moved by 1-10 μm along the line connected with the first capacitive plate pair connected with the capacitive displacement sensing circuit, and then the capacitive plate state is relatively balanced, so that the relationship between the voltage output by the capacitive displacement sensing circuit and the moving distance is obtained; then, the least square method is used for fitting, and the calibration coefficient of the capacitive displacement sensing circuit is obtained.

4. The ball support type stability detection device according to claim 2, characterized by The calibration method of the other two capacitive displacement sensing circuits is as follows: before assembling the device, the translation table is installed under the first capacitive plate in suspension; then, the micrometer on the translation table is adjusted, the first capacitive plate connected with the capacitive displacement sensing circuit is moved by 1-10 μm along the line connected with the second capacitive plate arranged opposite to the first capacitive plate, and then the capacitive plate state is relatively balanced, so that the relationship between the voltage output by the capacitive displacement sensing circuit and the moving distance is obtained; then, the least square method is used for fitting, and the calibration coefficient of the capacitive displacement sensing circuit is obtained.

5. The ball support type stability detection device according to claim 1, characterized by Four first capacitor plates are hung around the measured sphere through capacitor plate supports, the bases of the capacitor plate supports are fixed on two vibration isolation tables, and the two vibration isolation tables are arranged on opposite sides of the microcrystal disc.

6. The ball support type stability detection device according to claim 1, wherein Three invar support columns are adhered on the support ring, the upper end of the invar support column is a 45° section, and the section contacts the measured sphere through three specific points.

7. The ball support type stability detection device according to claim 1, wherein The microcrystal disc is placed on the support table.

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