A calibration and testing apparatus and method for a vibration sensor

Abstract

This invention provides a high-temperature vibration sensor calibration and measurement device and method. The device includes: a cavity, a vibration device, a first heating module, a signal acquisition module for the test signal, a signal module for absolute calibration and / or a signal module for comparison calibration, and a processor. The first heating module includes a base with a mounting position for mounting the vibration sensor under test, a first heating element, a first temperature sensor, and a first temperature control component. The first heating element is positioned below the mounting position and is in direct contact with the vibration sensor under test or indirectly in contact with it through the base, for heating the vibration sensor under test from its bottom. This effectively simulates the actual working environment of the sensor mounted on a surface heat source, improving the calibration accuracy of the sensor. Furthermore, by introducing inter-solid heat conduction, the heating rate and efficiency are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of vibration measurement and testing, and more particularly to a calibration and testing apparatus and method for a vibration sensor, especially a high-temperature vibration sensor. Background Technology

[0002] Vibration sensors are widely used in transportation, microelectronics, industrial manufacturing, and aerospace. By measuring the dynamic parameters of mechanical equipment, vibration sensors can determine the operating status of the equipment, thus playing a crucial role in structural health monitoring. In the aerospace field, extreme conditions such as high temperature, high pressure, vacuum, and strong radiation are frequently encountered. Ensuring that sensors can operate stably in extreme environments is both a significant challenge and a future trend in sensor development. Currently, there is a lack of devices on the market for calibrating and measuring high-temperature vibration sensors, which greatly hinders the research and development of high-temperature vibration sensors.

[0003] Some vibration sensors are prone to oxidation failure at high temperatures due to the sensitive elements. Most existing high-temperature calibration and measurement devices are exposed to air, making it impossible to calibrate sensors that are not encapsulated in a vacuum or inert gas. While some devices can calibrate high-temperature vibration sensors in a vacuum, their heating elements often employ a cage-like structure, where the heat source does not directly contact the sensor. This method relies solely on thermal radiation for heat transfer, resulting in low heating efficiency. Another drawback of the cage-like heating structure is that it can only simulate a uniform temperature field, while the actual environment in which vibration sensors operate often exhibits a certain temperature difference. Furthermore, in the aerospace field, sensors frequently operate in thin-air, high-altitude environments. For resistive vibration sensors, the resistance often changes with the type and amount of adsorbed gas. Therefore, how to calibrate vibration sensors sensitive to gas adsorption at high temperatures remains a pressing problem to be solved. Summary of the Invention

[0004] In view of the above problems, a calibration and testing apparatus and method for vibration sensors is proposed to overcome or at least partially solve the above problems.

[0005] One object of the first aspect of the present invention is to provide a calibration and testing apparatus for a vibration sensor employing a "contact" heating structure, thereby improving the heating rate and efficiency.

[0006] A further object of the first aspect of the invention is to be able to simulate the environment of different gases at different pressures, thereby more accurately calibrating or testing vibration sensors that are sensitive to gas adsorption.

[0007] Another further object of the first aspect of the invention is to simulate different uniform temperature fields, single heat source heated temperature gradient fields, or controllable specific temperature gradient fields, thereby calibrating or testing vibration sensors more accurately.

[0008] A second aspect of the present invention aims to provide a method for calibrating and testing a vibration sensor using the aforementioned calibration and testing apparatus.

[0009] In particular, according to one aspect of the present invention, a calibration and testing apparatus for a vibration sensor is provided, comprising:

[0010] A cavity, used to create the gaseous or vacuum environment required for calibrating and testing the vibration sensor under test;

[0011] A vibration device, at least partially disposed within the cavity, is used to provide vibration for the vibration sensor under test;

[0012] A first heating module, at least partially installed on the portion of the vibration device located within the cavity, the first heating module comprising:

[0013] A base having a mounting position for mounting the vibration sensor under test;

[0014] A first heating element is disposed below the mounting position and is in direct contact with the vibration sensor under test or indirect contact with the vibration sensor under test through the base, so as to heat the vibration sensor under test from the bottom of the vibration sensor under test.

[0015] A first temperature sensor is positioned near the mounting location to detect the temperature near the bottom of the vibration sensor under test; and

[0016] The first temperature control component is connected to the first temperature sensor and the first heating element, and is used to control the operation of the first heating element according to the temperature detected by the first temperature sensor and the first set temperature.

[0017] The signal acquisition module is connected to the vibration sensor under test and is used to acquire the test signal of the vibration sensor under test.

[0018] An absolute calibration signal module is used to provide a measurement signal for absolute calibration of the vibration sensor under test; and / or, a comparison calibration signal module is used to output a standard signal for comparison calibration; and

[0019] The processor is connected to the signal acquisition module under test, the absolute calibration signal module, and / or the comparison calibration signal module, respectively, and is used to display and process the test signal of the vibration sensor under test, and to calibrate the vibration sensor under test based on the test signal, the measurement signal, and / or the standard signal.

[0020] Optionally, the base includes a first base and a second base fixed together at an interval, the upper surface of the first base being provided with the mounting position, and the first heating element being a surface heat source and attached to the lower surface of the first base; and

[0021] The first heating module further includes:

[0022] A heat insulation layer is disposed below the first heating element, and is sandwiched between the first base and the second base together with the first heating element.

[0023] Optionally, the vibration device includes:

[0024] A signal generator is used to produce vibration signals;

[0025] A power amplifier, connected to the signal generator, for amplifying the signal from the signal generator; and

[0026] A vibration table is disposed within the cavity and connected to the power amplifier to vibrate based on the amplified signal, wherein the second base is mounted on the vibration table in a manner that is either without gap or at a specified distance from the table surface of the vibration table;

[0027] The signal module for absolute calibration includes:

[0028] A laser vibrometer, housed within the cavity and connected to the signal acquisition module, projects a measurement beam onto the surface of the vibration sensor under test and outputs the measurement signal to the signal acquisition module; or

[0029] A laser vibrometer, disposed outside the cavity and connected to the signal acquisition module under test, is used to generate a measurement beam and output the measurement signal to the signal acquisition module under test; and an optical window is used to focus the measurement beam of the laser vibrometer onto the surface of the vibration sensor under test.

[0030] The signal module for comparison method calibration includes:

[0031] A standard vibration sensor is installed inside the vibration table; and

[0032] A standard signal acquisition module is connected to the standard vibration sensor and the processor, and is used to acquire the standard signal output by the standard vibration sensor.

[0033] Optionally, the calibration and testing device for the vibration sensor further includes a second heating module, at least partially disposed within the cavity and located above the base, comprising:

[0034] An insulated cage is installed inside the cavity to maintain the temperature of the space inside the insulated cage;

[0035] The second heating element is located inside the insulation cage.

[0036] A telescopic fixing rod, connected to the insulation cage, is used to adjust the insulation cage and the second heating element in the relative direction between the center of the insulation cage and the center of the vibration sensor to be tested, so as to adjust the distance between them and the vibration sensor to be tested in the relative direction.

[0037] A second temperature sensor, located inside the insulation cage, is used to detect the temperature inside the insulation cage; and

[0038] The second temperature control component is connected to the second temperature sensor and the second heating element, and is used to control the operation of the second heating element according to the temperature detected by the second temperature sensor and the second set temperature;

[0039] In the case where the calibration and testing device includes the absolute method calibration signal module and the absolute method calibration signal module includes a laser vibrometer, the second heating module is provided with an opening at the location corresponding to the installation position, so as to allow the measurement beam emitted by the laser vibrometer to be incident on the surface of the vibration sensor under test.

[0040] Optionally, the calibration and testing apparatus for the vibration sensor further includes:

[0041] A movable temperature sensor, movably disposed within the cavity, is used to measure the temperature field inside the cavity; and / or

[0042] A vacuum pump assembly, connected to the cavity, is used to extract gas from the cavity to control the gas pressure or vacuum level within the cavity; and / or

[0043] An air inlet, located on the wall of the cavity, is used to introduce gases of different types or components into the cavity to obtain the desired gaseous environment; and / or

[0044] A barometer is installed in the cavity to measure the gas pressure inside the cavity.

[0045] Optionally, the signal acquisition module includes a first adapter circuit connected to the vibration sensor under test, and a first data acquisition unit connected to the first adapter circuit and the processor respectively.

[0046] The standard signal acquisition module includes a second adapter circuit connected to the standard vibration sensor, and a second data acquisition unit connected to the second adapter circuit and the processor respectively; wherein the first data acquisition unit and the second data acquisition unit are different or the same data acquisition unit;

[0047] The types of vibration sensors to be tested include piezoelectric, piezoresistive, and capacitive.

[0048] According to another aspect of the present invention, a method for calibrating and testing a vibration sensor using the aforementioned vibration sensor calibration and testing apparatus is also provided, comprising:

[0049] A gaseous or vacuum environment is created within the cavity to calibrate and test the vibration sensor under test.

[0050] Obtain the temperature environment required for calibrating and testing the vibration sensor under test;

[0051] A vibration signal is applied to the vibration sensor under test, and an absolute calibration measurement beam is applied to the vibration sensor under test through the absolute calibration signal module; or, a vibration signal is applied to both the vibration sensor under test and the standard vibration sensor in the comparison calibration signal module.

[0052] Acquire the test signal output by the vibration sensor under test and the measurement signal output by the absolute method calibration signal module; or, acquire the test signal output by the vibration sensor under test and the standard signal output by the comparison method calibration signal module.

[0053] Based on the test signal and the measurement signal, or based on the test signal and the standard signal, calculate the performance parameters of the vibration sensor under test, and calibrate the vibration sensor under test based on the calculation results.

[0054] Optionally, the calibration and testing apparatus further includes a vacuum pump assembly connected to the cavity for extracting gas from the cavity to control the gas pressure or vacuum level within the cavity; and / or an air inlet disposed on the wall of the cavity for introducing different types or components of gas into the cavity to obtain the desired gas environment.

[0055] The step of creating the gas or vacuum environment required for calibrating and testing the vibration sensor under test within the cavity includes:

[0056] The vacuum pump assembly is activated to evacuate the cavity, thereby creating a high-vacuum environment within the cavity; or

[0057] Control the vacuum pump assembly to extract a specified amount of air from the cavity to obtain an air environment with a specified pressure within the cavity; or

[0058] After the vacuum pump group is started to evacuate the air from the cavity, a gas of a predetermined type or composition is introduced into the cavity through the air inlet, and the amount of gas introduced into the cavity is controlled to obtain a gas environment with a predetermined pressure in the cavity.

[0059] Wherein, the specified pressure of the air environment or the predetermined pressure of the gas environment is 10. -9 Pa to 10 7 Any value within the range of Pa;

[0060] The gas includes inert gas, non-inert gas, or a mixture of both.

[0061] Optionally, the calibration and testing apparatus further includes a movable temperature sensor, which is movably disposed within the cavity for measuring the temperature field inside the cavity;

[0062] The step of obtaining the temperature environment required for calibrating and testing the vibration sensor under test includes:

[0063] For a vibration sensor under test with a thickness greater than or equal to a first thickness, the first heating module is activated to heat it to a first set temperature to simulate a temperature gradient field around the vibration sensor under test, simulating a single heat source heating. This temperature gradient field is then mapped using the movable temperature sensor. The value of the first thickness depends on the thermal conductivity of the vibration sensor under test.

[0064] For a vibration sensor under test with a thickness less than or equal to the second thickness, the first heating module is activated to heat it to the first set temperature to simulate the formation of a uniform temperature field around the vibration sensor under test. The value of the second thickness depends on the thermal conductivity of the vibration sensor under test.

[0065] Wherein, the first set temperature is any temperature value higher than room temperature.

[0066] Optionally, the calibration and testing apparatus further includes:

[0067] A movable temperature sensor, movably disposed within the cavity, is used to measure the temperature field inside the cavity; and

[0068] The second heating module, at least partially disposed within the cavity and located above the base, comprises:

[0069] An insulated cage is installed inside the cavity to maintain the temperature of the space inside the insulated cage;

[0070] The second heating element is located inside the insulation cage.

[0071] A telescopic fixing rod, connected to the insulation cage, is used to adjust the insulation cage and the second heating element in the relative direction between the center of the insulation cage and the center of the vibration sensor to be tested, so as to adjust the distance between them and the vibration sensor to be tested in the relative direction.

[0072] A second temperature sensor, located inside the insulation cage, is used to detect the temperature inside the insulation cage; and

[0073] The second temperature control component is connected to the second temperature sensor and the second heating element, and is used to control the operation of the second heating element according to the temperature detected by the second temperature sensor and the second set temperature;

[0074] The step of obtaining the temperature environment required for calibrating and testing the vibration sensor under test includes:

[0075] The second heating module is adjusted via the retractable fixing rod so that the distance H between the lowest point of the second heating module and the bottom of the vibration sensor under test in the relative direction is ≤0. The first heating element and the second heating element are then controlled to heat to a first set temperature T1 and a second set temperature T2 respectively to simulate a uniform temperature field around the vibration sensor under test, where T1 = T2; or

[0076] The second heating module is adjusted by the telescopic fixing rod so that the distance H = z between the lowest end of the second heating module and the bottom of the vibration sensor under test in the relative direction. The first heating element and the second heating element are respectively controlled to heat to the first set temperature T1 and the second set temperature T2 to simulate a specific temperature gradient field from T1 to T2 in the z range of the direction of the vibration sensor under test toward the second heating element. The temperature gradient field is plotted by the movable temperature sensor, where z is a real number greater than 0 and T1 ≠ T2.

[0077] Wherein, T1 and T2 are both any temperature values ​​higher than room temperature.

[0078] The vibration sensor calibration and testing apparatus and method provided by this invention have the following advantages compared with the prior art:

[0079] In the vibration sensor calibration and testing apparatus and method of the present invention, by employing a first heating module with a "contact" heating structure to heat one surface of the vibration sensor under test, the actual working environment of the sensor under test mounted on a surface heat source can be better simulated, thereby improving the calibration accuracy of the sensor. Furthermore, by introducing heat transfer through inter-solid thermal conduction, the heating rate and efficiency are significantly improved.

[0080] Furthermore, the vibration sensor calibration and testing apparatus and method of the present invention can provide an inert gas protective atmosphere or a vacuum environment, eliminating the need for complex packaging of the sensor. The vibration sensor can be directly calibrated or tested in a range from room temperature to 2000°C (preferably 25°C to 1500°C), reducing the calibration threshold and calibration cost of the vibration sensor.

[0081] Furthermore, the calibration and testing apparatus and method for vibration sensors of the present invention can provide gas environments of different types or components, enabling the calibration or testing of a type of vibration sensor sensitive to gas adsorption, such as a piezoresistive vibration sensor, thus filling the gap in gas adsorption calibration.

[0082] Furthermore, the calibration and testing apparatus and method for vibration sensors of the present invention can not only simulate an environment with a certain temperature difference, but also approximately simulate a uniform temperature environment for some thinner sensors (e.g., ≤10mm, preferably ≤5mm), thereby broadening its applicable scenarios.

[0083] Furthermore, the present invention introduces a heat insulation layer in the first heating module, which can prevent high temperature from being transmitted to the vibration table and avoid damage to the vibration table by high temperature. At the same time, it enables the standard sensor to calibrate the sensor under test in the high temperature zone at room temperature.

[0084] Furthermore, the calibration and testing apparatus and method for the vibration sensor of the present invention employs dual heat sources (i.e., a first heating module and a second heating module). In some embodiments, in a vacuum, setting the two heat sources to the same temperature value increases the heat conduction and transfer methods, heating the sensor under test from all directions and providing a more uniform temperature environment. In an atmosphere, the presence of the second heating module not only expands the heated area of ​​the sensor under test but also provides insulation, ensuring sufficient heating and enabling calibration and testing in a uniform temperature field. In other embodiments, by setting different temperature values ​​for the two heat sources and adjusting the telescopic fixing rod, a controllable specific temperature gradient field is created at the upper and lower ends of the sensor under test. This can be used to simulate more complex real-world environments, expanding the application range of the vibration sensor in practical scenarios.

[0085] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below.

[0086] The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0087] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0088] Figure 1 This is a schematic diagram of a calibration and testing apparatus for a vibration sensor according to an embodiment of the present invention;

[0089] Figure 2 This is a schematic diagram of the structure of a calibration and testing apparatus for a vibration sensor according to another embodiment of the present invention;

[0090] Figure 3 This is a schematic diagram of a first heating module according to an embodiment of the present invention;

[0091] Figure 4 This is a schematic diagram of a second heating module according to an embodiment of the present invention;

[0092] Figure 5 This is a top view of a first base according to an embodiment of the present invention;

[0093] Figure 6 This is a top view of the second base according to an embodiment of the present invention;

[0094] Figure 7 This is a flowchart illustrating a method for calibrating and testing a vibration sensor according to an embodiment of the present invention.

[0095] Figure 8 This is a flowchart illustrating a method for calibrating and testing a vibration sensor according to another embodiment of the present invention;

[0096] Figure 9 This is the output curve of the sensor under test calibrated in a vacuum at 600°C in Embodiment 1 of the present invention;

[0097] Figure 10 This is the output curve of the sensor under test tested in argon gas at 700°C in Example 3 of the present invention. Detailed Implementation

[0098] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0099] Embodiments of the present invention provide a calibration and testing apparatus for vibration sensors, which is particularly suitable for the calibration of high-temperature vibration sensors.

[0100] Figure 1 This is a schematic diagram of a calibration and testing apparatus for a vibration sensor according to an embodiment of the present invention. Figure 1 As shown, the calibration and testing device for the vibration sensor may include at least: a cavity 1 for creating a gaseous or vacuum environment within it for calibrating and testing the vibration sensor 5 under test; a vibration device, at least partially disposed within the cavity 1, for providing vibration to the vibration sensor 5 under test; a first heating module, at least partially mounted on the portion of the vibration device located within the cavity 1, for heating the vibration sensor 5 under test; a test signal acquisition module connected to the vibration sensor 5 under test for acquiring test signals from the vibration sensor 5 under test; an absolute calibration signal module for providing absolute calibration measurement signals to the vibration sensor 5 under test, and / or a comparison calibration signal module for outputting a comparison calibration standard signal; and a processor 23 connected to the test signal acquisition module, the absolute calibration signal module, and / or the comparison calibration signal module, respectively, for displaying and processing the test signals of the vibration sensor under test, and calibrating the vibration sensor under test based on the test signals, the measurement signals, and / or the standard signals.

[0101] Figure 3 This is a schematic diagram of a first heating module according to an embodiment of the present invention. See also... Figure 3 Specifically, the first heating module may include: a base having a mounting position for mounting the vibration sensor 5 to be tested; a first heating element 7 disposed below the mounting position and in direct contact with the vibration sensor 5 to be tested or indirect contact with the vibration sensor 5 to be tested through the base, for heating the vibration sensor 5 to be tested from the bottom; a first temperature sensor 4 disposed near the mounting position for detecting the temperature near the bottom of the vibration sensor 5 to be tested; and a first temperature control assembly 19 connected to the first temperature sensor 4 and the first heating element 7 for controlling the operation of the first heating element 7 according to the temperature detected by the first temperature sensor 4 and a first set temperature (T1).

[0102] The cavity 1 is a rigid structure with an invariable volume, capable of withstanding high vacuum, high temperature, and high pressure. The absolute calibration signal module and the comparison calibration signal module only need to generate the absolute calibration measurement signal and the comparison calibration standard signal for the vibration sensor; existing absolute calibration equipment and comparison calibration equipment can be used. The processor 23 can be any processing device capable of implementing the above-described display, processing, and calibration functions; for example, the processor 23 can be a computer. The data processing and implementation processes for the absolute and comparison calibration of the vibration sensor mentioned herein should be well known to those skilled in the art, and will not be described in detail here to avoid obscuring the focus of the invention.

[0103] Traditional high-temperature vibration sensor calibration devices in the prior art mostly employ a "cage-type" structure to heat the sensor under test. The advantage of this method is that it can simulate a relatively uniform temperature field, thus fully heating the sensor. However, since vibration sensors are often mounted on the surface of a heat source, their actual working environment is not in a uniform temperature field but rather in an environment with a temperature gradient. This leads to deviations in the actual operation of sensors calibrated using this method. For example, some materials may exhibit thermoelectric effects, generating thermoelectric electromotive force in environments with temperature differences, affecting the sensor's output value. Compared to existing technologies, the vibration sensor calibration and testing device provided in this embodiment, by employing a "contact-type" heating structure, heats only one surface of the vibration sensor under test through its first heating module. This better simulates the actual working environment of the sensor mounted on a surface heat source, improving the sensor's calibration accuracy.

[0104] In the field of high-temperature vibration sensor calibration, vacuum level is also a crucial parameter affecting sensor performance. Current thermal vacuum systems still employ the traditional "cage-type" heating structure. In a vacuum, this "non-contact" structure can only heat the sensor under test through thermal radiation, resulting in a very slow heating rate and low efficiency. The "contact" structure proposed in the vibration sensor calibration and testing device provided in this embodiment, in addition to thermal radiation, also incorporates heat conduction within the solid, significantly improving the heating rate and efficiency.

[0105] Furthermore, compared to traditional heating structures, the first heating module in the vibration sensor calibration and testing kit of the present invention has the advantages of small size, simple structure, detachability, easy installation / replacement, and portability.

[0106] Furthermore, since an absolute calibration signal module and / or a comparison calibration signal module are provided, the vibration sensor calibration and testing apparatus of the present invention can be used to calibrate or test the vibration sensor under test using the absolute method and / or the comparison method.

[0107] When heating is performed solely using the first heating module, for a vibration sensor under test with a thickness greater than or equal to a first thickness (d1), the calibration and testing device for the vibration sensor of the present invention can simulate the temperature gradient field of a single heat source in a real environment, realizing the testing of the vibration sensor under test in the temperature gradient field T = f(x,y,z). The value of d1 depends on the thermal conductivity of the vibration sensor under test. Optionally, the value of d1 is 1 mm. Preferably, the value of d1 is 5 mm.

[0108] In some further embodiments, the calibration and testing apparatus for the vibration sensor may also include a movable temperature sensor 18, movably disposed within the cavity 1, for measuring the temperature field inside the cavity 1. For example, the movable temperature sensor 18 is used to measure the temperature gradient field T = f(x,y,z) around the vibration sensor 5 under test.

[0109] When heating is performed using only the first heating module, for vibration sensors under test with a thickness less than or equal to the second thickness (d2), the calibration and testing device for vibration sensors of the present invention can approximately simulate a uniform temperature, enabling calibration or testing of the vibration sensors under test in a uniform temperature field. The d2 value depends on the thermal conductivity of the vibration sensor under test. Optionally, the d2 value is 10 mm. Preferably, the d2 value is 5 mm.

[0110] As can be seen, the calibration and testing device for the vibration sensor of the present invention can not only simulate an environment with a certain temperature difference, but also approximately simulate a temperature-uniform environment for some thinner sensors (e.g., ≤10mm, preferably ≤5mm). Within the allowable temperature error range, the temperature of the thinner sensor can be approximately considered to be equal everywhere, thereby enabling the calibration of such vibration sensors in a uniform temperature field.

[0111] See also Figure 1 In some embodiments, the base includes a first base 6 and a second base 10 fixed together at an interval. The mounting position is provided on the upper surface of the first base 6, and the first heating element 7 is a surface heat source and is attached to the lower surface of the first base 6. The first heating module further includes a heat insulation layer 8, which is disposed below the first heating element 7 and sandwiched between the first base 6 and the second base 10 together with the first heating element 7.

[0112] Figure 5 A top view of a first base 6 according to an embodiment of the present invention is shown. Figure 6 A top view of a second base 10 according to an embodiment of the present invention is shown. See also, in some specific embodiments... Figure 5 and Figure 6As shown, the first base 6 has one first screw hole 6-2 and N second screw holes 6-3 reserved, where N is a positive integer greater than or equal to 2. The second base 10 has one third screw hole 10-1 and N fourth screw holes 10-2 reserved, with the N fourth screw holes 10-2 corresponding one-to-one with the N second screw holes 6-3. The first screw hole 6-2 is located at the center of the first base 6 and is used to install the vibration sensor 5 to be tested. The third screw hole 10-1 is located at the center of the second base 10 and is used to install the first heating module onto the part of the vibration device located inside the cavity 1. The second screw holes 6-3 are centrally symmetrically distributed about the first screw hole 6-2, and the fourth screw holes 10-2 are centrally symmetrically distributed about the third screw hole 10-1. The center distance between the first screw hole 6-2 and the second screw hole 6-3 is the same as the center distance between the third screw hole 10-1 and the fourth screw hole 10-2. N bolts 9 pass through the corresponding second screw holes 6-3 and fourth screw holes 10-2, respectively, to fix the first base 6 and the second base 10 together, thereby tightly fixing the first heating element 7 and the heat insulation layer 8 below it between the first base 6 and the second base 10. In this way, the first heating element 7 transfers heat to the vibration sensor 5 under test through solid-to-solid thermal conduction, and the heating rate can reach ≥50℃ / min, which greatly improves the heating rate and efficiency.

[0113] The first temperature sensor 4 is mounted on the first base 6 through the fixing hole 6-1. The first temperature control assembly 19 controls the first heating element 7 to heat to the first set temperature and maintain a stable temperature by comparing the detected value of the first temperature sensor 4 with the first set temperature (T1). The heat insulation layer 8 is used to isolate the heat transfer between the first heating element 7 and the vibration device to prevent high temperature damage to the vibration device.

[0114] Preferably, the heat insulation layer 8 can be made of lightweight ceramic material that is earthquake-resistant and thermally shock-resistant.

[0115] Preferably, the first heating element 7 can be manufactured using a ceramic-embedded resistance wire process. Preferably, the ceramic in the first heating element 7 is made of a ceramic material with high mechanical strength and high temperature resistance. Preferably, when the operating temperature is higher than 1000°C, the resistance wire inside the first heating element 7 can be made of nickel-based alloy, tungsten wire, or platinum wire.

[0116] Preferably, when the calibration or testing temperature is higher than 800°C, the first base 6, the second base 10, and the bolt 9 are made of high-temperature resistant materials, including but not limited to high-temperature metals, high-temperature alloys, and ceramic-metal composite materials.

[0117] Preferably, the bolt 9, the first base 6, and the second base 10 are made of the same material or materials with similar coefficients of thermal expansion to avoid structural cracking or loosening caused by high-temperature thermal expansion.

[0118] See also Figure 1In some embodiments, the vibration device includes: a signal generator 21 for generating vibration signals; a power amplifier 20 connected to the signal generator 21 for amplifying the signals from the signal generator 21; and a vibration table 2 disposed within the cavity 1 and connected to the power amplifier 20 for vibration based on the amplified signals. That is, the vibration table 2, the power amplifier 20, and the signal generator 21 are connected to form a vibration device for generating physical vibrations of a certain waveform, amplitude, and frequency; the signal generator 21 generates a certain driving signal, which is amplified by the power amplifier 20, causing the vibration table 2 to vibrate accordingly. The second base 10 is mounted on the vibration table 2 with no gap or at a specified distance from the table surface 3. The heat insulation layer 8 can isolate heat transfer between the first heating element 7 and the table surface 3 of the vibration table 2, preventing high-temperature damage to the vibration table 2. Preferably, a certain space (i.e., a specified distance) is left between the second base 10 and the table surface 3 of the vibration table 2, thereby further isolating heat transfer between the first heating element 7 and the table surface 3 of the vibration table 2.

[0119] Optionally, a vibration isolation device is placed at the bottom of the vibration table 2 to isolate it from environmental vibrations.

[0120] In some embodiments, the signal module for absolute method calibration may include a laser vibrometer 32, disposed within the cavity 1 and connected to the signal acquisition module under test, for projecting a measurement beam onto the surface of the vibration sensor 5 under test and outputting a measurement signal to the signal acquisition module under test. The working principle of the laser vibrometer should be known to those skilled in the art and will not be described further here.

[0121] In other embodiments, the signal module for absolute calibration may include: a laser vibrometer 32, disposed outside the cavity 1 and connected to the signal acquisition module under test, for generating a measurement beam and outputting a measurement signal to the signal acquisition module under test; and a transparent optical window 31 for focusing the measurement beam of the laser vibrometer 32 onto the surface of the vibration sensor 5 under test or the surface of the first base 6. Preferably, the optical window 31 is located directly above the vibration sensor 5 under test. The laser vibrometer 32 focuses the incident light as a measurement beam onto the surface of the vibration sensor 5 under test or the surface of the first base 6 through the optical window 31 to measure the vibration of the vibration sensor 5 under test. The photoelectric converter converts the vibration measurement result into an electrical signal, which is then acquired by the signal acquisition module under test and sent to the computer 23 for display, processing, and calculation to achieve the calibration of the vibration sensor 5 under test. It should be noted that, for the sake of simplifying the image representation, Figure 1 and Figure 2 The connection between the laser vibration meter 32 and the signal acquisition module under test is not shown, but those skilled in the art should recognize that the two can be connected by a signal line.

[0122] In some embodiments, the signal module for comparative calibration may include: a standard vibration sensor 11, installed inside the vibration table 2; and a standard signal acquisition module, connected to the standard vibration sensor 11 and the processor 23, for acquiring the standard signal output by the standard vibration sensor 11. Specifically, the standard vibration sensor 11 is placed directly below the table surface 3 of the vibration table 2 for calibrating the vibration sensor 5 under test. Protected by the heat insulation layer 8, the standard vibration sensor 11 can accurately calibrate the vibration sensor 5 under test, which is located in a high-temperature region, at room temperature.

[0123] See also Figure 1 In some embodiments, the cavity 1 is provided with a first aviation plug 14 and a second aviation plug 15, which are used to lead the signal line inside the cavity 1 to the outside of the cavity while ensuring the airtightness of the cavity 1.

[0124] Specifically, the first temperature control component 19, the signal acquisition module under test and the standard signal acquisition module are located outside the cavity 1, and the first aviation plug 14 is used to lead the signal lines of the first heating element 7, the first temperature sensor 4, the standard vibration sensor 11 and the vibration sensor under test 5 out of the cavity 1 and connect them to the corresponding components.

[0125] The power amplifier 20 and the signal generator 21 are located outside the cavity 1. The second aviation plug 15 is used to lead the signal line of the vibration table 2 out of the cavity 1 and connect it to the power amplifier 20.

[0126] The first aviation connector 14 and the second aviation connector 15 can be different aviation connectors or the same aviation connector. The total number of aviation connectors can be determined according to actual conditions and requirements, but must be at least one.

[0127] Preferably, the aviation connector can be an aviation connector with anti-electromagnetic interference function, thereby preventing the collected signal from being affected by electromagnetic interference and improving the accuracy of the collected signal.

[0128] In other embodiments, the first temperature control component 19, the signal acquisition module under test, the standard signal acquisition module, and the processor 23 can also be directly disposed inside the cavity 1, thus eliminating the need for an aviation connector.

[0129] See also Figure 1 The signal acquisition module may include a first adapter circuit 16 connected to the vibration sensor 5 under test, and a first data acquisition unit 22a connected to the first adapter circuit 16 and the processor 23 respectively. The first adapter circuit 16 is used to condition the output signal of the vibration sensor 5 under test so that the signal is adapted to the first data acquisition unit 22a. The first adapter circuit 16 may use different adapter circuits depending on the type of vibration sensor under test.

[0130] Similarly, the standard signal acquisition module may include a second adapter circuit 17 connected to the standard vibration sensor 11, and a second data acquisition unit 22b connected to the second adapter circuit 17 and the processor 23, respectively. The second adapter circuit 17 is used to condition the output signal of the standard vibration sensor 11 to adapt the signal to the second data acquisition unit 22b. The second adapter circuit 17 may employ different adapter circuits depending on the type of standard vibration sensor.

[0131] The first data acquisition unit 22a and the second data acquisition unit 22b can be different or the same data acquisition unit, preferably the same data acquisition unit, thereby reducing the number of components and reducing costs.

[0132] Those skilled in the art will understand that the measurement signal from the laser vibrometer 32 is converted into an electrical signal by a photoelectric converter, and then acquired by the third data acquisition unit (not shown in the figure) before being sent to the processor 23. The third data acquisition unit may also be the same data acquisition unit as the first data acquisition unit 22a and the second data acquisition unit 22b.

[0133] Figure 2 This is a schematic diagram of the structure of a calibration and testing apparatus for a vibration sensor according to another embodiment of the present invention. Figure 4 This is a schematic diagram of a second heating module according to an embodiment of the present invention. See also... Figure 2 and Figure 4 As shown, in some embodiments, the calibration and testing apparatus for the vibration sensor may further include a second heating module, which is at least partially disposed within the cavity 1 and located above the base, for heating the area around and above the vibration sensor 5 to be tested.

[0134] Specifically, the second heating module may include: a heat preservation cage 25, disposed within the cavity 1, for maintaining the temperature of the internal space of the heat preservation cage 25; a second heating element 26, located within the internal space of the heat preservation cage 25; a telescopic fixing rod 24, connected to the heat preservation cage 25, for adjusting the heat preservation cage 25 and the second heating element 26 in the relative direction between the center of the heat preservation cage 25 and the center of the vibration sensor 5 to be tested, so as to adjust the distance between them and the vibration sensor 5 to be tested in the relative direction; a second temperature sensor 27, located within the internal space of the heat preservation cage 25, for detecting the internal temperature of the heat preservation cage 25; and a second temperature control component 28, connected to the second temperature sensor 27 and the second heating element 26, for controlling the operation of the second heating element 26 according to the temperature detected by the second temperature sensor 27 and the second set temperature (T2), so as to drive the second heating element 26 to heat to the second set temperature and maintain temperature stability. Preferably, the second heating element 26 is a surface heat source that is adapted to the shape of the insulation cage 25 (e.g., conformal) and is attached to the inner surface of the insulation cage 25, thereby further ensuring uniform temperature distribution inside the insulation cage. The telescopic fixing rod 24 can achieve the best heating effect by adjusting the height of the second heating element 26 and the insulation cage 25, and also facilitates the installation and disassembly of other components.

[0135] Optionally, an opening is provided at the location of the second heating module corresponding to the installation position of the vibration sensor under test, so that the measuring beam emitted by the laser vibrometer 32 is incident on the surface of the vibration sensor 5 under test when using the absolute method for calibration. Specifically, openings are provided at the locations of the insulation cage 25 and the second heating element 26 corresponding to the installation position of the vibration sensor under test.

[0136] In some embodiments, the second temperature control component 28 is disposed outside the cavity 1, and the cavity 1 is also provided with a third aviation connector 29 for leading the signal lines of the second heating element 26 and the second temperature sensor 27 out of the cavity 1 and connecting them to the second temperature control component 28. In other embodiments, the second temperature control component 28 may also be disposed directly inside the cavity 1, thus eliminating the need for an aviation connector.

[0137] Because a second heating module is provided, with H as the distance between the lowest point of the second heating module and the bottom of the vibration sensor 5 under test in the relative direction, in some embodiments, when the first heating module and the second heating module are used simultaneously, by adjusting the telescopic fixing rod 24 to make H=0, the heating temperature of the first heating module is set to T1, and the heating temperature of the second heating module is set to T2, so that T1=T2, the vibration sensor 5 under test can be heated in all directions and uniformly.

[0138] In other embodiments, by adjusting the telescopic fixing rod 24 to move the second heating module away from the vibration sensor 5 under test, making H = z (z is a real number greater than 0), and then making the temperatures T1 and T2 unequal, a specific temperature gradient field from T1 to T2 within the z range in the direction of the vibration sensor 5 towards the second heating element 26 can be simulated. At this time, the temperature gradient field can be plotted using the movable temperature sensor 28.

[0139] Optionally, both T1 and T2 are above room temperature. That is, both T1 and T2 are any temperatures above room temperature, and T1 and T2 may be equal or unequal.

[0140] Optionally, both T1 and T2 include any temperature in the range from above room temperature to 3000°C.

[0141] Optionally, both T1 and T2 include any temperature in the range from above room temperature to 2000°C.

[0142] Optionally, both T1 and T2 include any temperature within the range of 25℃ to 1500℃.

[0143] Optionally, both T1 and T2 include any temperature within the range of 25℃ to 1200℃.

[0144] Optionally, both T1 and T2 include any temperature within the range of 25℃ to 1000℃.

[0145] Optionally, both T1 and T2 include any temperature within the range of 25℃ to 800℃.

[0146] Optionally, both T1 and T2 include any temperature within the range of 400℃ to 1500℃.

[0147] Optionally, both T1 and T2 include any temperature within the range of 400℃-1200℃.

[0148] Optionally, both T1 and T2 include any temperature within the range of 600℃-1200℃.

[0149] Optionally, both T1 and T2 include any temperature within the range of 800℃-1200℃.

[0150] Optionally, both T1 and T2 include any temperature within the range of 600℃-1000℃.

[0151] The vibration sensor calibration and testing device in this embodiment employs dual heat sources (i.e., a first heating module and a second heating module). In some implementations, setting both heat sources to the same temperature value in a vacuum increases heat conduction and transfer, allowing for comprehensive heating of the sensor under test and providing a more uniform temperature environment. In an atmosphere, the presence of the second heating module not only expands the heated area of ​​the sensor but also provides insulation, ensuring sufficient heating and enabling calibration and testing within a uniform temperature field. In other implementations, setting different temperature values ​​for the two heat sources and adjusting the telescopic fixing rod creates specific temperature fields at the upper and lower ends of the sensor under test. This can be used to simulate more complex real-world environments, expanding the application range of the vibration sensor in practical scenarios.

[0152] See also Figure 1 In some embodiments, the calibration and testing apparatus for the vibration sensor may also include a vacuum pump assembly 12 connected to the cavity 1 for extracting gas from the cavity 1 to control the gas pressure or vacuum level within the cavity 1.

[0153] Optionally, the cavity 1 is also equipped with a pressure gauge 30 for detecting the gas pressure and vacuum level inside the cavity 1.

[0154] Optionally, the cavity 1 is also provided with a water cooling device (not shown in the figure) for cooling the cavity 1.

[0155] In some embodiments, the calibration and testing apparatus for the vibration sensor may further include an air inlet 13 disposed on the wall of the cavity 1, for introducing different types or components of gas into the cavity 1 to obtain the desired gas environment. The air inlet 13 may be a through hole penetrating the wall of the cavity 1, and the number of such holes may be greater than or equal to one.

[0156] The introduced gas may be a single gas or a mixture of two or more gases.

[0157] A single gas may include inert gases, including but not limited to helium, neon, and argon. A single gas may also include non-inert gases, including but not limited to nitrogen, oxygen, carbon dioxide, and water vapor.

[0158] The proportions of the gas components in the mixed gas are not limited, including but not limited to mixtures of oxygen / nitrogen, oxygen / water vapor / carbon dioxide / nitrogen, etc.

[0159] The pressure of the gas environment inside cavity 1 can be 10. -9 Pa to 10 7 Any value within the range of Pa.

[0160] The vacuum pump type used in vacuum pump unit 12 includes, but is not limited to, mechanical pumps, molecular pumps, ion pumps, etc.

[0161] The vacuum pump assembly 12 is used to extract gas from the cavity 1 to obtain gas at a specific pressure, thereby enabling a variety of testing functions, including but not limited to: simulating the atmospheric environment of a planet and testing the performance of a vibration sensor under different pressures.

[0162] Because some sensitive elements in vibration sensors are prone to oxidation and failure at high temperatures, existing technologies require protective encapsulation of the sensors during high-temperature vibration sensor calibration. The vibration sensor calibration and testing apparatus of this invention provides an inert gas protective atmosphere or vacuum environment, eliminating the need for complex sensor encapsulation. It allows direct calibration or testing of vibration sensors within a temperature range above room temperature up to 2000°C (preferably 25°C to 1500°C), lowering the calibration threshold and cost for vibration sensors.

[0163] Furthermore, based on different operating principles, vibration sensors can be categorized into piezoresistive, piezoelectric, and capacitive types. For piezoresistive vibration sensors, the resistance changes with the type and amount of gas adsorbed. The vibration sensor calibration and testing apparatus of this invention can provide gas environments of different types or compositions, enabling the calibration or testing of vibration sensors sensitive to gas adsorption, such as piezoresistive vibration sensors, thus filling a gap in gas adsorption calibration. Therefore, this invention is applicable to the calibration and testing of piezoelectric, piezoresistive, and capacitive vibration sensors.

[0164] Based on the same inventive concept, the present invention also provides a method for calibrating and testing a vibration sensor using the aforementioned calibration and testing device for vibration sensors.

[0165] Figure 7 This is a schematic flowchart illustrating a method for calibrating and testing a vibration sensor according to an embodiment of the present invention. In one embodiment, see... Figure 7 As shown, the method for calibrating and testing the vibration sensor may include at least the following steps S702 to S710.

[0166] S702: Create the gas or vacuum environment required for calibrating and testing the vibration sensor 5 under test within the cavity 1.

[0167] S704: Obtain the temperature environment required for calibrating and testing the vibration sensor 5 under test.

[0168] S706: Apply a vibration signal to the vibration sensor 5 under test, and apply an absolute calibration measurement beam to the vibration sensor 5 under test through the absolute calibration signal module.

[0169] S708: Acquire the test signal output by the vibration sensor 5 under test and the measurement signal output by the absolute calibration signal module.

[0170] S710: Based on the test signal and the measurement signal, calculate the performance index parameters of the vibration sensor 5 under test, and calibrate the vibration sensor 5 under test based on the calculation results.

[0171] Performance parameters include at least one of sensitivity, linearity, and phase.

[0172] The method in this embodiment enables absolute calibration and testing of vibration sensors.

[0173] Figure 8 This is a schematic flowchart illustrating a method for calibrating and testing a vibration sensor according to another embodiment of the present invention. In another embodiment, see... Figure 8 As shown, the method for calibrating and testing the vibration sensor may include at least the following steps S802 to S810.

[0174] S802: Create the gas or vacuum environment required for calibrating and testing the vibration sensor 5 under test within the cavity 1.

[0175] S804: Obtain the temperature environment required for calibrating and testing the vibration sensor 5 under test.

[0176] S806: Simultaneously apply vibration signals to the vibration sensor 5 under test and the standard vibration sensor 11 in the comparison calibration signal module.

[0177] S808: Acquire the test signal output by the vibration sensor 5 under test and the standard signal output by the comparison calibration signal module.

[0178] S810: Based on the test signal and the standard signal, calculate the performance parameters of the vibration sensor 5 under test, and calibrate the vibration sensor 5 under test based on the calculation results.

[0179] The method in this embodiment enables comparative calibration and testing of vibration sensors.

[0180] In some further embodiments, step S702 or S802 may specifically include:

[0181] The vacuum pump unit 12 is started to evacuate the cavity 1, thereby creating a high-vacuum environment within the cavity 1; or

[0182] The vacuum pump assembly 12 is controlled to extract a specified amount of air from the cavity 1 to obtain an air environment with a specified pressure within the cavity 1; or

[0183] After the vacuum pump unit 12 is started to evacuate the air in the cavity 1, a gas of a predetermined type or composition is introduced into the cavity 1 through the air inlet 13, and the amount of gas introduced into the cavity 1 is controlled to obtain a gas environment with a predetermined pressure in the cavity 1.

[0184] The specified pressure of the air environment or the predetermined pressure of the gas environment inside cavity 1 is 10. -9 Pa to 10 7 Any value within the range of Pa.

[0185] The gas used for filling is as described above and will not be repeated here.

[0186] This embodiment can provide an inert gas protective atmosphere, a vacuum environment, or a gas environment of different types or compositions to adapt to the calibration and testing of vibration sensors for different occasions and needs.

[0187] In some further embodiments, the first heating module can be used alone to heat and create the desired temperature environment. Specifically, step S704 or S804 may include:

[0188] For the vibration sensor 5 under test with a thickness greater than or equal to a first thickness, the first heating module is activated to heat it to a first set temperature (T1) to simulate a temperature field around the vibration sensor 5 heated by a single heat source. The temperature field is then measured by the movable temperature sensor 18. The value of the first thickness depends on the thermal conductivity of the vibration sensor 5 under test; or

[0189] For the vibration sensor 5 under test with a thickness less than or equal to the second thickness, the first heating module is activated to heat it to the first set temperature (T1) to simulate the formation of a uniform temperature field around the vibration sensor 5 under test. The value of the second thickness depends on the thermal conductivity of the vibration sensor 5 under test.

[0190] For example, the first thickness can be 1 mm. For example, the second thickness can be 10 mm.

[0191] In some further embodiments, the first heating module and the second heating module can be used simultaneously to heat and create the desired temperature environment. Specifically, step S704 or S804 may include:

[0192] The second heating module is adjusted by the telescopic fixing rod 24 so that the distance H between the lowest point of the second heating module and the bottom of the vibration sensor 5 under test in the aforementioned relative direction is ≤0. The first heating element 7 and the second heating element 26 are respectively controlled to heat to the first set temperature T1 and the second set temperature T2 to simulate the formation of a uniform temperature field around the vibration sensor 5 under test, where T1 = T2; or

[0193] The second heating module is adjusted by the telescopic fixing rod 24 so that the distance H = z between the lowest end of the second heating module and the bottom of the vibration sensor 5 under test in the aforementioned relative direction. The first heating element 7 and the second heating element 26 are respectively controlled to heat to the first set temperature T1 and the second set temperature T2 to simulate a specific temperature gradient field from T1 to T2 in the vertical direction z range of the space above the vibration sensor 5 under test. The temperature gradient field is plotted by the movable temperature sensor 18, where z is a real number greater than 0 and T1 ≠ T2.

[0194] The limitations of T1 and T2 are as described above and will not be repeated here.

[0195] It should be noted that the orientations or positional relationships indicated by terms such as "upper," "lower," "top," "bottom," "inner," and "outer" described herein are based on the orientations or positional relationships shown in the accompanying drawings. They are used solely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. The placement orientation of the vibration sensor calibration and testing device in this invention is not limited; it can be placed according to... Figure 1 and Figure 2 It can be placed vertically as shown, or horizontally, or in any direction.

[0196] The above describes various embodiments of the calibration and testing apparatus and method for the vibration sensor of the present invention. The following specific examples illustrate the embodiments of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0197] Example 1

[0198] In this embodiment, only the first heating module is used to calibrate the vibration sensor 5 under test in a vacuum. The vacuum pump group 12 is started to completely evacuate the gas from the cavity 1. When the vacuum level reaches 0.1 Pa, the first heating module is started, with the temperature set to 600℃ and the heating rate set to 50℃ / min. The sensor 5 under test is heated to the set temperature and held at that temperature for a period of time until the temperature stabilizes. At different frequencies and accelerations, the standard vibration sensor 11 is used to calibrate or test the vibration sensor 5 under test. Figure 9 The output curves of the vibration sensor under test 5 and the standard vibration sensor 11 under 500Hz sinusoidal excitation are compared. The vibration sensor under test 5 is a resistive high-temperature resistant accelerometer with a thickness of about 3mm, so the temperature around the vibration sensor under test can be approximated as uniform.

[0199] Actual test results show that the output of the standard vibration sensor 11 exhibits a standard sine curve, and no vibration distortion caused by the heating module was observed. The phase of the vibration sensor under test 5 is also basically consistent with that of the standard vibration sensor 11, indicating that the phase of the vibration can also be transmitted to the vibration sensor under test 5 without delay. This demonstrates that the high-temperature vibration sensor calibration and testing device and method provided by this invention are feasible, and the calibration and measurement results are reliable.

[0200] This embodiment enables the calibration or testing of the vibration sensor under test in a vacuum: (1) it is used to simulate the space environment; (2) it does not require high-temperature resistant packaging of the vibration sensor under test, and can calibrate some vibration sensors with poor oxidation resistance, which greatly reduces the cost of calibration or testing.

[0201] Example 2

[0202] In this embodiment, only the first heating module is used. The vacuum pump group 12 is started to completely evacuate the gas from the cavity 1. Then, an inert gas, including but not limited to nitrogen, argon, and helium, is introduced through the inlet 13. The temperature of the first heating module is set to the desired value (25℃-1500℃), and the heating rate is set to 50℃ / min. The vibration sensor 5 under test is heated to the set temperature and held for a period of time until the temperature stabilizes. The vibration sensor 5 under test is calibrated using the absolute method. The measuring beam of the laser vibrometer 32 is focused onto the surface of the vibration sensor 5 under test through the optical window 31. Vibration measurements are performed on the vibration sensor 5 under test at different frequencies (1Hz-10kHz) and accelerations. Then, the above operation is repeated to achieve vibration calibration of the vibration sensor 5 under test at different temperatures.

[0203] Achieving calibration or testing in a uniform temperature field: For the vibration sensor 5 under test with a thickness less than d2, this scheme can be approximated as a uniform temperature. The value of d2 depends on the thermal conductivity of the vibration sensor under test; preferably, d2 is 1-5 mm.

[0204] Achieving calibration or testing with temperature differences: In the actual working environment of sensors, there exists a certain temperature difference. For some vibration sensors under test with thermoelectric effects, this may generate a thermoelectric electromotive force output, affecting the sensor's accuracy. This scheme can simulate a heat source in the actual environment to calibrate or test the vibration sensor under test in an environment with a certain temperature difference. By controlling the height of the movable temperature sensor 18, the temperature gradient field T = f(x,y,z) around the vibration sensor under test 5 can be obtained.

[0205] This solution can provide an inert gas atmosphere, thus enabling the calibration of some vibration sensors that are prone to oxidation and failure in high-temperature air, without the need for high-temperature resistant packaging of the sensors, which is beneficial for the research and development and testing of high-temperature resistant vibration sensors.

[0206] Example 3

[0207] This embodiment uses only the first heating module to test the vibration sensor under test in an environment with a certain temperature difference. The vacuum pump group 12 is started to completely evacuate the gas from the cavity 1. Then, argon gas is introduced through the inlet 13 until the internal pressure of the cavity reaches 1 atm. Next, the temperature of the first heating module is set to 700℃, and the heating rate is set to 50℃ / min. The vibration sensor under test 5 is heated to the set temperature and held for a period of time until the temperature stabilizes. At different frequencies and accelerations, the vibration sensor under test 5 is calibrated or tested using a standard vibration sensor 11. The thickness of the vibration sensor under test 5 is 10mm, and the surrounding temperature difference is not negligible. Its bottom is in contact with the heat source at a temperature of 700℃, and its top temperature is approximately 600℃, with a temperature difference of approximately 100℃ between the top and bottom. Figure 10 The output curves of the vibration sensor under test 5 and the standard vibration sensor 11 under 2kHz sinusoidal excitation are compared.

[0208] The test results show that the outputs of the vibration sensor under test 5 and the standard vibration sensor 11 almost overlap, indicating that the vibration sensor under test has excellent vibration response performance and that the present invention can provide an accurate vibration excitation environment. This embodiment demonstrates the feasibility and reliability of the device of the present invention in testing vibration sensors in a temperature difference environment.

[0209] Example 4

[0210] This embodiment uses only the first heating module. The temperature of the first heating module is set to 1000℃, the heating rate is set to 100℃ / min, and it is kept at that temperature for a period of time until the temperature of the vibration sensor 5 under test reaches a stable level. By controlling the amount of air extracted from the cavity 1 by the vacuum pump group 12, any pressure value less than atmospheric pressure (20-101kPa) can be obtained, thereby simulating the working environment of an aircraft engine at different altitudes. By controlling the height of the movable temperature sensor 18, the temperature gradient field T = f(x,y,z) around the vibration sensor 5 under test can be measured. In this case, the vibration sensor 5 under test is calibrated or tested using a comparison method or an absolute method to further improve the calibration accuracy of the sensor.

[0211] In addition to simulating the aforementioned special scenarios, this solution can also calibrate or measure some resistive vibration sensors that are sensitive to gas adsorption. Under different gas concentrations, the resistance of the sensitive element in a resistive sensor may change. This solution can accurately obtain the relationship between the vacuum level (or gas concentration) and the initial resistance and vibration response output of the vibration sensor under test.

[0212] Example 5

[0213] This embodiment uses only the first heating module. The temperature of the first heating module is set, and the vibration sensor 5 under test is heated to the set temperature value (25℃-1500℃) and kept at that temperature for a period of time until the temperature stabilizes. The vacuum pump group 12 is started to completely evacuate the gas from the cavity 1. Then, the required gas is introduced into the air inlet 13. By adjusting the amount of gas introduced and coordinating with the vacuum pump group 12, a specific atmospheric pressure environment can be obtained. The pressure can be greater than one atmosphere or a certain value less than atmospheric pressure, simulating the atmospheric atmosphere of certain planets. In this case, a standard vibration sensor 11 is used to measure the sensitivity, linearity, and phase of the vibration sensor 5 under test at different atmospheric pressures.

[0214] By resetting the temperature of the first heating module and repeating the above steps, data on the sensitivity, linearity, and phase of the vibration sensor 5 under test can be obtained at different temperatures and pressures. This method can achieve calibration or testing of vibration sensors in the aerospace and military fields under any gas atmosphere and pressure.

[0215] Example 6

[0216] The calibration and testing device for the vibration sensor in this embodiment may also include a second heating module.

[0217] The second heating module is as follows Figure 4 As shown, it includes: a telescopic fixing rod 24, an insulation cage 25, a second heating element 26, a second temperature sensor 27, and a second temperature control component 28.

[0218] The second heating module is placed directly above the vibration sensor 5 under test and is used to heat the area around the vibration sensor 5 under test.

[0219] The second temperature sensor 27 is located inside the insulation cage 25.

[0220] The insulation cage 25 is used to maintain a constant temperature inside the insulation cage.

[0221] The second temperature control component 28 controls the second heating element 26 to heat to the set temperature value and maintain a stable temperature by comparing the second temperature sensor 27 with the set temperature value.

[0222] The telescopic fixing rod 24 adjusts the height of the second heating module so that the height of the lowest end of the second heating module is lower than or equal to the height of the bottom of the vibration sensor 5 under test. That is, by adjusting the height so that H≤0, the vibration sensor under test can be fully covered to achieve the best heating effect.

[0223] The first heating module and the second heating module are set to the same temperature value, thereby simulating a uniform temperature field in all areas.

[0224] Vacuum pump unit 12 evacuates the high-temperature resistant cavity 1 to achieve a vacuum environment.

[0225] In this case, the comparative method or the absolute method is used to calibrate or test the vibration sensor 5 under test. This scheme uses dual heat sources to heat the vibration sensor under test from all directions, which makes up for the shortcomings of traditional heaters that heat the sensor under test only through thermal radiation in a vacuum, greatly improving heating efficiency and making the heating more uniform.

[0226] Example 7

[0227] The calibration and testing device for the vibration sensor in this embodiment may also include a second heating module.

[0228] The second heating module is as follows Figure 4 As shown, it includes: a telescopic fixing rod 24, an insulation cage 25, a second heating element 26, a second temperature sensor 27, and a second temperature control component 28.

[0229] The second heating module is placed directly above the vibration sensor 5 under test, and is used to heat the area around and above the vibration sensor 5 under test.

[0230] The second heating module has an opening at the top, which allows the laser vibration meter 32 to focus the incident light onto the surface of the vibration sensor 5 or the first base 6 to achieve vibration measurement.

[0231] The second temperature sensor 27 is located inside the insulation cage 25.

[0232] The insulation cage 25 is used to maintain a constant internal temperature.

[0233] The second temperature control component 28 controls the second heating element 26 to heat to the set temperature value and maintain a stable temperature by comparing the measured value of the second temperature sensor 27 with the set temperature value.

[0234] The telescopic fixing rod 24 is connected to the insulation cage 25 and is used to adjust the height of the second heating element 26 to achieve the best heating effect, while also facilitating the disassembly of other components.

[0235] The temperature of the first module is set to T1, and the temperature of the second heating module is set to T2. The telescopic fixing rod is adjusted so that H = z (z is a real number greater than 0). By controlling the temperatures of T1 and T2, a continuous temperature gradient field simulation from T1 to T2 within the vertical direction z in space is achieved. In this case, the laser vibrometer 32 is used to perform absolute calibration on the vibration sensor 5 under test. This embodiment can meet the calibration requirements of some special application sensors or high-precision sensors.

[0236] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0237] Therefore, those skilled in the art should recognize that although numerous exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications conforming to the principles of the present invention can be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Thus, the scope of the present invention should be understood and construed as covering all such other variations or modifications.

Claims

1. A calibration and testing device for a vibration sensor, characterized in that The device comprises: a cavity for forming a gas or vacuum environment required for calibrating and testing a vibration sensor to be tested; a vibration device arranged at least partially in the cavity for providing vibration to the vibration sensor to be tested; a first heating module mounted at least partially on a portion of the vibration device located in the cavity, the first heating module comprising: a base having a mounting position for mounting the vibration sensor to be tested; a first heating element arranged below the mounting position and in direct contact with or indirectly contact with the vibration sensor to be tested through the base for heating the vibration sensor to be tested from the bottom of the vibration sensor to be tested; a first temperature sensor arranged near the mounting position for detecting the temperature near the bottom of the vibration sensor to be tested; and a first temperature control assembly connected with the first temperature sensor and the first heating element for controlling the operation of the first heating element according to the temperature detected by the first temperature sensor and a first set temperature; a signal acquisition module connected with the vibration sensor to be tested for acquiring a test signal of the vibration sensor to be tested; an absolute method calibration signal module for providing a measurement signal for absolute method calibration of the vibration sensor to be tested; and / or a comparison method calibration signal module for outputting a standard signal for comparison method calibration; and a processor connected with the signal acquisition module, the absolute method calibration signal module and / or the comparison method calibration signal module respectively for displaying and processing the test signal of the vibration sensor to be tested and calibrating the vibration sensor to be tested based on the test signal and the measurement signal and / or the standard signal.

2. The calibration and testing device of a vibration sensor according to claim 1, wherein the base comprises a first base and a second base fixed together with a spacing therebetween, an upper surface of the first base is provided with the mounting position, and the first heating element is a surface heat source and is attached to a lower surface of the first base; and the first heating module further comprises: a heat insulation layer arranged below the first heating element to be clamped together with the first heating element between the first base and the second base.

3. The calibration and testing device of a vibration sensor according to claim 2, wherein the vibration device comprises: a signal generator for generating a vibration signal; a power amplifier connected with the signal generator for amplifying the signal from the signal generator; and a vibration table arranged in the cavity and connected with the power amplifier for vibration based on the amplified signal, wherein the second base is mounted on the vibration table with no spacing or a specified spacing distance from a table surface of the vibration table; the absolute method calibration signal module comprises: a laser vibration meter arranged in the cavity and connected with the signal acquisition module for projecting a measurement light beam to a surface of the vibration sensor to be tested and outputting the measurement signal to the signal acquisition module; or a laser vibration meter arranged in the cavity and connected with the signal acquisition module for projecting a measurement light beam to a surface of the vibration sensor to be tested and outputting the measurement signal to the signal acquisition module; or a laser vibrometer disposed outside the cavity and connected to the signal acquisition module to be measured, for generating a measurement beam and outputting the measurement signal to the signal acquisition module to be measured; and an optical window for focusing the measurement beam of the laser vibrometer to the surface of the vibration sensor to be measured; the comparison method calibration signal module comprises: a standard vibration sensor mounted inside the vibration table; and a standard signal acquisition module connected to the standard vibration sensor and the processor for acquiring the standard signal output by the standard vibration sensor.

4. The calibration and testing apparatus of a vibratory sensor according to claim 1, characterized in that, It also includes a second heating module, at least partially disposed in the cavity and above the base, which includes: a heat preservation cage disposed in the cavity for maintaining the temperature of the internal space of the heat preservation cage; a second heating element located in the internal space of the heat preservation cage; a telescopic fixing rod connected to the heat preservation cage for adjusting the heat preservation cage and the second heating element along the relative direction between the center of the heat preservation cage and the center of the vibration sensor to be measured to adjust the distance between them and the vibration sensor to be measured in the relative direction; a second temperature sensor located in the internal space of the heat preservation cage for detecting the temperature inside the heat preservation cage; and a second temperature control assembly connected to the second temperature sensor and the second heating element for controlling the operation of the second heating element according to the temperature detected by the second temperature sensor and the second set temperature; wherein, in the case that the calibration and testing device includes the absolute method calibration signal module and the absolute method calibration signal module includes a laser vibrometer, the second heating module is provided with an opening corresponding to the mounting position for allowing the measurement beam emitted by the laser vibrometer to be incident on the surface of the vibration sensor to be measured.

5. A calibration and test device for a vibratory sensor according to any one of claims 1-4, characterized in that, It also includes: a movable temperature sensor movably disposed in the cavity for measuring the temperature field inside the cavity; and / or a vacuum pump group connected to the cavity for extracting gas in the cavity to control the gas pressure or vacuum degree in the cavity; and / or an air inlet provided on the wall of the cavity for introducing different kinds or components of gas into the cavity to obtain the required gas environment; and / or an air pressure gauge provided in the cavity for measuring the gas pressure in the cavity.

6. The calibration and testing device of the vibration sensor according to claim 3, wherein the signal acquisition module to be measured includes a first adaptive circuit connected to the vibration sensor to be measured, and a first data acquisition unit connected to the first adaptive circuit and the processor, respectively; the standard signal acquisition module includes a second adaptive circuit connected to the standard vibration sensor, and a second data acquisition unit connected to the second adaptive circuit and the processor, respectively; wherein the first data acquisition unit and the second data acquisition unit are different or the same data acquisition unit; the type of the vibration sensor to be measured includes piezoelectric, piezoresistive and capacitive.

7. A method of calibrating and testing a vibration sensor using a calibration and testing apparatus of any one of claims 1-3, characterized in that, includes: forming a gas or vacuum environment in the cavity required for calibration and testing of the vibration sensor to be tested; obtaining a temperature environment required for calibration and testing of the vibration sensor to be tested; applying a vibration signal to the vibration sensor to be tested and applying a measurement light beam for absolute method calibration to the vibration sensor to be tested by the signal module for absolute method calibration; or, simultaneously applying a vibration signal to the vibration sensor to be tested and a standard vibration sensor in the signal module for comparative method calibration; acquiring a test signal output by the vibration sensor to be tested and a measurement signal output by the signal module for absolute method calibration; or, acquiring a test signal output by the vibration sensor to be tested and a standard signal output by the signal module for comparative method calibration; calculating a performance index parameter of the vibration sensor to be tested based on the test signal and the measurement signal, or based on the test signal and the standard signal, and calibrating the vibration sensor to be tested based on the calculation result.

8. The method of calibration and testing of a vibratory sensor according to claim 7, characterized in that, The calibration and testing device further comprises a vacuum pump set connected to the cavity for extracting gas in the cavity to control the gas pressure or vacuum degree in the cavity; and / or a gas inlet provided on the wall of the cavity for introducing different kinds or components of gas into the cavity to obtain a required gas environment. The step of forming a gas or vacuum environment in the cavity required for calibration and testing of the vibration sensor to be tested comprises: starting the vacuum pump set to perform vacuum extraction on the cavity to form a high vacuum degree vacuum environment in the cavity; or controlling the vacuum pump set to extract a specified amount of air from the cavity to obtain a specified pressure air environment in the cavity; or after the vacuum pump set exhausts the air in the cavity, introducing a predetermined kind or component of gas into the cavity through the gas inlet, and controlling the amount of gas filled into the cavity to obtain a predetermined pressure gas environment in the cavity; wherein the specified pressure of the air environment or the predetermined pressure of the gas environment is any value in the range of 10 -9 Pa to 10 7 Pa. The gas includes inert gas, non-inert gas, or a mixture of the two.

9. A method of calibration and testing of a vibratory sensor according to claim 7 or 8, characterised in that, The calibration and testing device further comprises a movable temperature sensor movably arranged in the cavity for measuring the temperature field inside the cavity. The step of obtaining a temperature environment required for calibration and testing of the vibration sensor to be tested comprises: for a vibration sensor to be tested with a thickness greater than or equal to a first thickness, starting the first heating module to heat to a first set temperature to simulate a single heat source heating temperature gradient field around the vibration sensor to be tested, and mapping the temperature gradient field by the movable temperature sensor, the value of the first thickness being determined according to the thermal conductivity coefficient of the vibration sensor to be tested; or for a vibration sensor to be tested with a thickness less than or equal to a second thickness, starting the first heating module to heat to the first set temperature to simulate a uniform temperature field around the vibration sensor to be tested, the value of the second thickness being determined according to the thermal conductivity coefficient of the vibration sensor to be tested; wherein the first set temperature is any temperature value higher than room temperature.

10. The method of calibration and testing of a vibration sensor according to claim 7 or 8, characterized in that, The calibration and testing device further comprises: a movable temperature sensor movably arranged in the cavity for measuring a temperature field inside the cavity; and a second heating module arranged at least partially in the cavity and above the base, comprising: a heat preservation cage arranged in the cavity for maintaining a temperature of an inner space of the heat preservation cage; a second heating element arranged in the inner space of the heat preservation cage; a telescopic fixing rod connected to the heat preservation cage for adjusting the heat preservation cage and the second heating element along a relative direction between a center of the heat preservation cage and a center of the vibration sensor to be tested, so as to adjust a distance between them and the vibration sensor to be tested in the relative direction; a second temperature sensor arranged in the inner space of the heat preservation cage for detecting a temperature inside the heat preservation cage; and a second temperature control assembly connected to the second temperature sensor and the second heating element for controlling the operation of the second heating element according to the temperature detected by the second temperature sensor and a second set temperature; the step of obtaining a temperature environment required for calibrating and testing the vibration sensor to be tested comprises: adjusting the second heating module by the telescopic fixing rod to make a distance H between a lowest end of the second heating module and a bottom of the vibration sensor to be tested in the relative direction be less than or equal to 0, respectively controlling the first heating element and the second heating element to heat to a first set temperature T1 and a second set temperature T2 to simulate a uniform temperature field around the vibration sensor to be tested, wherein T1=T2; or adjusting the second heating module by the telescopic fixing rod to make the distance H between the lowest end of the second heating module and the bottom of the vibration sensor to be tested in the relative direction be equal to z, respectively controlling the first heating element and the second heating element to heat to the first set temperature T1 and the second set temperature T2 to simulate a specific temperature gradient field from T1 to T2 within a range of z in a direction of the vibration sensor to be tested towards the second heating element, and mapping the temperature gradient field by the movable temperature sensor, wherein z is a real number greater than 0 and T1≠T2; wherein the T1 and T2 are any temperature values higher than room temperature.

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