A multi-purpose calibration adapter for surface microphones and calibration method thereof

Abstract

The present invention discloses a multi-purpose surface microphone calibration adapter device, comprising a main body and an upper cover that are movably connected. A sealed surface microphone fixing cavity is formed between the main body and the upper cover. The main body is provided with an acoustic coupling cavity connected to the surface microphone fixing cavity and a lower frequency limit calibration sound transmission hole connected to the surface microphone pressure equalization hole, wherein the lower frequency limit calibration sound transmission hole is connected to the acoustic coupling cavity. A pressure spring is provided on the upper cover. Also disclosed is a method for calibrating a surface microphone using the multi-purpose surface microphone calibration adapter device. The adapter device can be directly connected to conventional calibration equipment to perform surface microphone lower frequency limit testing, microphone dynamic range upper limit testing, and sound calibration testing, thereby achieving versatility of the calibration equipment and greatly simplifying the surface microphone calibration method. The calibration is convenient, fast, and highly accurate.

Description

Technical Field

[0001] The present invention relates to the technical field of microphone calibration, and in particular to a multi-purpose calibration adapter device for a surface microphone and a calibration method thereof. Background Art

[0002] The dimensions and shapes of conventional microphones are specified in relevant standards such as IEC and GB. Currently, conventional microphone outer diameters range from 1 / 8 inch (3.5mm), 1 / 4 inch (7mm), 1 / 2 inch (13.2mm), and 1 inch (23.77mm). Heights are generally greater than 8mm. Other specific dimensions are also regulated by relevant national standards. To ensure accurate measurements, pre-use calibration of the microphone is essential. The calibration equipment used with conventional microphones is designed to meet conventional dimensions, resulting in a comprehensive suite of calibration and testing equipment. Well-established calibration equipment for conventional microphones is available, and both domestic and international products are compatible.

[0003] Surface microphones are a relatively specialized type of microphone, primarily used for surface wind noise testing on products such as automobiles and spacecraft. Surface microphones have a unique shape, being flat and having a small aspect ratio. They typically have a diameter of 20mm-60mm, a height of 2mm-8mm, and a generally cylindrical shape.

[0004] Surface microphones differ significantly from conventional microphones in appearance. This difference prevents them from being calibrated using conventional microphone calibration equipment, requiring specialized calibration equipment. This significantly inconveniences microphone calibration, requiring specialized calibration equipment specifically for surface microphones, preventing the interoperability of conventional and surface microphone calibration equipment.

[0005] For example, a Chinese patent document (published on August 31, 2016, with publication number CN105916093B) discloses a surface microphone calibration device, specifically designed for surface microphones, a specialized type of microphone. This device, specifically designed for the non-standard flat structure of surface microphones, incorporates a novel flat asymmetric short coupling cavity structure, a flat, large-diameter pressure cap structure, and an independent, simplified surface microphone cover structure. This ensures consistency and sealing between the received sound fields of the surface microphone and those of a standard microphone, while also ensuring compatibility with surface microphones of varying sizes. Compared to existing calibration devices designed for conventional microphones, this calibration device is specifically designed for surface microphones, improving both calibration accuracy and device versatility. However, the device's design specifically for surface microphones has the main drawback of being inconvenient to use and lacking universal applicability. While this calibration device, specifically designed for surface microphones, can achieve universal calibration of surface microphones of varying sizes, it lacks the compatibility between conventional microphones and surface microphone calibration equipment. That is, it is not possible to meet the calibration requirements of a surface microphone using a conventional microphone calibration device.

[0006] Therefore, there is an urgent need to design a multi-purpose surface microphone calibration adapter. This multi-purpose calibration adapter can enable surface microphones to be calibrated using conventional calibration equipment, achieving universal calibration equipment and improving the efficiency and speed of surface microphone calibration. This multi-purpose calibration adapter can be matched with conventional microphone calibration equipment to meet the calibration requirements of surface microphone sensitivity, upper dynamic range limit, and lower frequency limit. Summary of the Invention

[0007] The purpose of the present invention is to solve the problem that existing surface microphones cannot be calibrated using conventional calibration equipment, which makes plane microphone calibration inconvenient and affects calibration accuracy. The present invention designs a multi-purpose calibration adapter for surface microphones that can be quickly connected to conventional calibration equipment and a calibration method thereof. Through the multi-purpose calibration adapter, it is possible to calibrate the surface microphone using the existing microphone sensitivity calibration system, microphone dynamic range calibration system and microphone lower frequency limit calibration system.

[0008] The technical solution adopted by the present invention to achieve its first invention object is: a multi-purpose calibration adapter for a surface microphone, comprising a main body and an upper cover that are movably connected, a sealed surface microphone fixing cavity formed between the main body and the upper cover, an acoustic coupling cavity connected to the surface microphone fixing cavity and a lower frequency limit calibration sound transmission hole connected to the surface microphone pressure equalizing hole are provided on the main body, the lower frequency limit calibration sound transmission hole being connected to the acoustic coupling cavity; and a pressure spring is provided on the upper cover. This multi-purpose surface microphone calibration adapter is designed with a main body and an upper cover. A surface microphone fixing cavity is formed between the main body and the upper cover for fixing the surface microphone and performing surface microphone calibration. Since surface microphone calibration includes surface microphone lower frequency limit testing, microphone dynamic range upper limit testing, and acoustic calibration testing, in order to implement these surface microphone lower frequency limit testing, microphone dynamic range upper limit testing, and acoustic calibration testing using existing calibration equipment, an acoustic coupling cavity is provided on the main body. When the surface microphone is installed in the surface microphone fixing cavity and connected to conventional calibration equipment, a sealed acoustic coupling cavity is formed between the main body and the surface microphone. The acoustic coupling cavity achieves acoustic resonance for calibration. Since the surface microphone's pressure equalizing hole needs to be exposed to the sound field during surface microphone lower frequency limit calibration, a lower frequency limit calibration sound transmission hole is provided on the main body that connects to the surface microphone pressure equalizing hole, thereby transmitting the sound during calibration to the surface microphone pressure equalizing hole. In order to fix the surface microphone during the calibration process and ensure the stability of the calibration in the sound field, a pressure spring is provided on the upper cover to fix the surface microphone. The surface microphone is fixed by the pressure spring, thereby protecting the surface microphone in the sound field during the calibration process to have good stability and ensure the accuracy of the calibration. The multi-purpose calibration adapter for surface microphones can be directly connected to the existing microphone lower frequency limit calibration system, microphone dynamic range calibration system and microphone sensitivity calibration system to achieve surface microphone lower frequency limit test, microphone dynamic range upper limit test and sound calibration test without the need for setting up special surface microphone calibration equipment. It realizes the universality of calibration equipment between surface microphones and conventional microphones, and the calibration is convenient, fast and accurate, reducing the cost of manufacturing special calibration equipment for surface microphones and greatly improving the calibration efficiency of the microphone calibration industry.

[0009] Preferably, the acoustic coupling cavity has a volume of 450 mm³ to 455 mm³. To achieve accurate calibration, the cavity volume of the acoustic coupling cavity is precisely calculated based on surface microphone calibration. A cavity volume that is too small will result in an overly large calibration value, while a cavity volume that is too large will result in an underlying calibration value. Therefore, the cavity volume of the acoustic coupling cavity is generally designed to be between 450 mm³ and 455 mm³. This numerical range allows for accurate surface microphone calibration.

[0010] Preferably, the surface microphone mounting cavity is provided with an output wire slot, and a lead sealing pin for outputting the surface microphone's signal output line is inserted within the output wire slot. To connect the surface microphone output line to an external measurement amplifier and accurately output calibration data, an output wire slot is provided in the surface microphone mounting cavity. During calibration, the signal output line on the surface microphone extends through the output wire slot and connects to the external measurement amplifier. Since the surface microphone mounting cavity requires good sealing performance, a sealing pin is inserted within the output wire slot to seal the output wire slot and lead out the signal output line.

[0011] Preferably, the main body includes an integrally arranged main body acoustic body, a main body base, and a main body connector. The acoustic coupling cavity is arranged along the axis of the main body acoustic body. A through hole connecting to the acoustic coupling cavity is radially arranged on the main body acoustic body. The lower frequency limit calibration acoustic hole is arranged perpendicular to the through hole, and the axis of the lower frequency limit calibration acoustic hole is parallel to the axis of the main body acoustic body. The above-mentioned structure of the main body facilitates the fixing of the surface microphone and the rapid connection with conventional calibration equipment. Therefore, the main body is integrally provided with a main body acoustic body for connecting to conventional calibration equipment or a housing and transmitting calibration sound, a main body base for fixing the surface microphone and achieving stable calibration of the surface microphone, and a main body connector for connecting to the upper cover to fix the surface microphone and form a surface microphone fixing cavity. A through hole is set on the main sound-transmitting body, one is to realize the connection between the sound-transmitting cavity and the frequency lower limit calibration sound-transmitting hole, and the other is to facilitate the blocking of the connection between the sound-transmitting cavity and the frequency lower limit calibration sound-transmitting hole by a sealing plug, thereby meeting the calibration requirements of different functions and meeting the design requirements of versatility and universality.

[0012] Preferably, a surface microphone mounting cavity is provided inside the main body, a sealed cavity is provided at the connection between the surface microphone mounting cavity and the acoustic coupling cavity, and a cavity seal is provided inside the sealed cavity. The surface microphone calibration is performed inside the surface microphone fixing cavity. To achieve the setting of the surface microphone fixing cavity, a surface microphone mounting cavity is provided inside the main body. Since the surface microphone calibration is performed inside the surface microphone fixing cavity, the surface microphone fixing cavity needs to have good sealing performance to achieve calibration accuracy. Therefore, a sealed cavity is provided at the connection between the surface microphone mounting cavity and the acoustic coupling cavity, and a cavity seal is provided inside the sealed cavity. When the surface microphone is fixed inside the surface microphone mounting cavity, a seal is formed between the lower surface of the surface microphone and the cavity seal. The lower surface of the surface microphone, the sealed cavity, and the acoustic coupling cavity together form a closed acoustic coupling cavity during the calibration process, ensuring calibration accuracy.

[0013] Preferably, the upper cover comprises a coaxially arranged connecting outer cover body and a pressurized inner cover body, wherein the connecting outer cover body and the pressurized inner cover body form an outer cover cavity, the pressurized inner cover body is provided with an inner cover cavity, the pressurized inner cover body is provided with an end face sealing groove, and the end face sealing groove is provided with an end face sealing member. The upper cover is provided with a connecting outer cover body and a pressurized inner cover body, wherein the outer cover cavity is used to achieve a sealed connection with the main body to form a surface microphone fixing cavity, and secondly, to achieve fixation of the surface microphone to protect stability during calibration. Therefore, the upper cover is provided with a connecting outer cover body and a pressurized inner cover body, wherein the outer cover cavity is used to achieve a connection with the main body and, at the same time, to achieve a sealing of the surface microphone mounting cavity to prevent sound leakage and unsealing during calibration. The inner cover cavity is used to cooperate with the surface microphone mounting cavity on the main body to form a surface microphone fixing cavity, and the pressurized spring is used to directly contact the surface microphone during calibration, and is therefore provided at the center of the inner cover cavity to achieve pressurized fixation of the surface microphone. The surface microphone fixing cavity needs to have good sealing performance. Therefore, an end face sealing groove is provided on the end face of the pressurized inner cover body, and an end face sealing member is provided inside the end face sealing groove. The surface microphone fixing cavity is sealed by the cooperation between the end face sealing member and the surface of the main seat body. The end face sealing member and the cavity sealing member jointly realize the sealing of the surface microphone fixing cavity during the surface microphone calibration process, thereby protecting the accuracy of the calibration.

[0014] Preferably, the device includes a jacket comprising an integrally formed dynamic upper limit calibration connector and a jacket body, a high sound pressure transmission chamber disposed within the dynamic upper limit calibration connector, a jacket sealing groove disposed on the inner wall of the jacket body, and a jacket seal disposed within the jacket sealing groove. To connect the calibration adapter to conventional calibration equipment to perform microphone dynamic range upper limit testing on a surface microphone, a jacket is provided comprising a dynamic upper limit calibration connector for connection to a microphone dynamic range calibration system and a jacket body for connection to the main body. To ensure sealing during the calibration process, a jacket sealing groove is disposed on the inner wall of the jacket body, and a jacket seal is disposed within the jacket sealing groove.

[0015] Preferably, the device also includes a sealing plug for blocking the lower frequency calibration sound transmission hole from the pressure-equalizing hole connected to the surface microphone. Because the connection between the sound transmission cavity and the lower frequency calibration sound transmission hole needs to be blocked during microphone dynamic range upper limit testing and acoustic calibration testing of the surface microphone, the sealing plug is quick and easy to use and allows for universal configuration of the entire device.

[0016] The technical solution adopted by the present invention to achieve the second invention object is: a method for calibrating using a multi-purpose calibration adapter for a surface microphone, comprising the following steps:

[0017] Step 1: Install the surface microphone: Remove the upper cover by rotating it, and place the surface microphone into the surface microphone mounting cavity inside the main body. Extend the signal output line of the surface microphone through the sealing pin and connect it to the external measurement amplifier. Then tighten the upper cover. The pressurized spring at the center of the pressurized inner cover pressurizes and fixes the surface microphone into the surface microphone mounting cavity. At this point, the end face seal on the pressurized inner cover is sealed to the surface of the main body, and the cavity seal is sealed to the surface of the surface microphone.

[0018] Step 2: Surface microphone lower frequency limit test: Install the main microphone body assembled in step 1 into the microphone lower frequency limit calibration system to calibrate the lower frequency limit of the surface microphone;

[0019] Step 3: Acoustic calibration test of the surface microphone: Insert a sealing plug into the through-hole of the main body assembled in step 1 to seal the through-hole and block the connection between the lower frequency limit calibration sound transmission hole and the through-hole. Then, install the main body sound transmission body into the sound calibrator and form a sealed connection between it and the inner wall of the sound calibrator. Turn on the sound calibrator to calibrate the surface microphone.

[0020] Step 4: Test the upper limit of the dynamic range of the surface microphone: Place the main microphone assembled in step 3 into the outer shell and form a sealed connection with the outer shell. Then insert the dynamic upper limit calibration connector on the outer shell into the microphone dynamic range upper limit calibration device. Send a detection signal to the microphone dynamic range upper limit calibration device, and emit high sound pressure. The high sound pressure is transmitted to the acoustic coupling cavity through the high sound pressure transmission cavity inside the dynamic upper limit calibration connector on the outer shell, thereby calibrating the upper limit of the dynamic range of the surface microphone.

[0021] Preferably, in step 2, the main body microphone is installed in the cavity of the microphone lower frequency limit calibration system and is sealed therewith, and the acoustic coupling cavity inside the main body microphone is connected to the cavity; a test signal is sent to the microphone lower frequency limit calibration system, and this signal is transmitted to the pressure equalizing hole on the surface microphone through the connected cavity, acoustic coupling cavity, through hole, and lower frequency limit calibration sound transmission hole, thereby realizing calibration of the lower frequency limit of the surface microphone.

[0022] The beneficial effects of the present invention are as follows: the multi-purpose surface microphone calibration adapter can be directly connected to existing microphone lower frequency limit calibration systems, microphone dynamic range calibration systems, and microphone sensitivity calibration systems to perform surface microphone lower frequency limit testing, microphone dynamic range upper limit testing, and acoustic calibration testing without the need for separate dedicated surface microphone calibration equipment. This achieves the commonality of calibration equipment between surface microphones and conventional microphones, and provides convenient, fast, and highly accurate calibration, reducing the cost of manufacturing dedicated surface microphone calibration equipment and significantly improving calibration efficiency in the microphone calibration industry. The surface microphone calibration method is greatly simplified, allowing calibration tests to be performed directly using the methods for conventional microphones. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a structural schematic diagram of a multi-purpose calibration adapter for a surface microphone according to the present invention;

[0024] Figure 2 It is a structural diagram of the main body in the present invention;

[0025] Figure 3 It is a structural schematic diagram of the main body of the present invention from another angle;

[0026] Figure 4 This is a structural schematic diagram of the upper cover in the present invention;

[0027] Figure 5 It is a structural schematic diagram of the jacket of the present invention;

[0028] Figure 6 This is a structural schematic diagram of the jacket of the present invention from another angle;

[0029] Figure 7 It is a structural schematic diagram of the connection between the multi-purpose calibration adapter device of the surface microphone of the present invention and the microphone frequency lower limit calibration system;

[0030] Figure 8 This is a structural diagram of a multi-purpose calibration adapter for a surface microphone in Example 2 of the present invention;

[0031] Figure 9 This is a structural diagram of the connection between the multi-purpose calibration adapter device of the surface microphone and the upper limit calibration device of the dynamic range of the microphone according to the present invention;

[0032] Figure 10 This is a structural diagram of a multi-purpose calibration adapter for a surface microphone in Example 3 of the present invention;

[0033] Figure 11 This is a structural diagram of the connection between the multi-purpose calibration adapter device of the surface microphone of the present invention and the sound calibrator;

[0034] In the figure: 100, surface microphone, 101, signal output line, 102, equalizing hole, 200, external measurement amplifier, 300, microphone frequency lower limit calibration system, 301, sound source, 302, cavity, 400, microphone dynamic range upper limit calibration device, 500, sound calibrator;

[0035] 1. Main body, 2. Upper cover, 3. Main sound conductor, 31. Acoustic coupling cavity, 32. Through hole, 33. Frequency lower limit calibration sound conductor hole, 4. Main seat, 41. Surface microphone mounting cavity, 42. Sealed cavity, 43. Cavity seal, 44. Output line slot, 45. Sealing pin, 5. Main connector, 51. Connecting external thread, 6. Connecting outer cover, 61. Connecting internal thread, 7. Pressurized inner cover, 71. Inner cavity of cover, 72. Pressurized spring, 73. End face sealing groove, 74. End face seal, 8. Inner cavity of cover, 9. Jacket, 10. Sealing plug, 11. Dynamic upper limit calibration connector, 12. Jacket main body, 13. High sound pressure transmission cavity, 14. Jacket sealing groove, 15. Jacket seal. DETAILED DESCRIPTION

[0036] The various aspects of the present invention are described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0037] Example 1:

[0038] exist Figure 1 In the illustrated embodiment, a multi-purpose surface microphone calibration adapter includes a main body 1 and an upper cover 2 that are movably connected. A sealed surface microphone fixing cavity 24 is formed between the main body 1 and the upper cover 2. The main body 1 is provided with an acoustic coupling cavity 31 connected to the surface microphone fixing cavity 24 and a lower frequency limit calibration sound transmission hole 33 connected to the surface microphone pressure equalizing hole. The lower frequency limit calibration sound transmission hole 33 is connected to the acoustic coupling cavity 31. A pressure spring 72 is provided on the upper cover 2.

[0039] like Figure 2 、 Figure 3 As shown, the main body 1 includes an integrally arranged main sound-transmitting body 3, a main body base body 4 and a main body connecting body 5. The main sound-transmitting body 3 is arranged in a cylindrical structure, the main body base body 4 is extended outward along the main sound-transmitting body 3 in a disk structure, and the main body connecting body 5 is arranged upward along the disk surface of the main body base body 4 in a ring structure.

[0040] The acoustic coupling cavity 31 is arranged along the axis of the main acoustic body 3 and extends through the main body base 4. A through hole 32 is radially provided on the main acoustic body 3, connecting to the acoustic coupling cavity 31. A lower-frequency calibration hole 33 is arranged perpendicular to the through hole 32. The lower-frequency calibration hole 33 connects the through hole 32 and the main body base 4, and the axis of the lower-frequency calibration hole 33 is parallel to the axis of the main acoustic body 3. The cavity volume of the acoustic coupling cavity 31 is designed based on precise calculations of surface microphones. An excessively small cavity volume will result in an overly large calibration value, while an excessively large cavity volume will result in an underlying calibration value. To ensure accurate calibration, the cavity volume of the acoustic coupling cavity 31 is generally designed to be between 450 mm³ and 455 mm³. In this embodiment, the cavity volume is 452.2 mm³.

[0041] The main body 4 is provided with a surface microphone mounting cavity 41. A sealed cavity 42 is provided at the connection between the surface microphone mounting cavity 41 and the acoustic coupling cavity 31. A cavity seal 43 is provided within the sealed cavity 42. During calibration, the surface microphone 100 is pressed against the cavity seal 43. A seal is formed between the lower surface of the surface microphone and the cavity seal. The lower surface of the surface microphone, the sealed cavity, and the acoustic coupling cavity together form a sealed acoustic coupling cavity during calibration, ensuring calibration accuracy. The surface microphone pressure equalization hole is generally located on the output line side. An output line slot 44 is provided on the side of the main body 4, parallel to the through-hole 32. A lead sealing pin 45 is inserted within the output line slot 44. The signal output line 101 of the surface microphone 100 extends outward through the sealing pin 45 and connects to the external measurement amplifier 200.

[0042] The outer ring surface of the main connecting body 5 is provided with a connecting external thread 51 .

[0043] like Figure 4As shown, the upper cover 2 is an annular cover structure, comprising a coaxially arranged outer cover 6 and a pressurized inner cover 7. A cover cavity 8 is formed between the outer cover 6 and the pressurized inner cover 7. The outer cover 6 is internally provided with connecting internal threads 61 that mate with the connecting external threads 51 on the main body connector 5. The pressurized inner cover 7 is internally provided with a cover cavity 71. The diameter of the cover cavity 71 is configured to mate with the surface microphone 100 and corresponds to the surface microphone mounting cavity 41 within the main body 4. The cover cavity 71 and the surface microphone mounting cavity 41 together form the surface microphone mounting cavity 24. A pressurized spring 72 is disposed at the center of the cover cavity 71 of the pressurized inner cover 7. During use, the pressurized spring 72 applies a certain elastic pressure to the surface microphone, stably securing it within the surface microphone mounting cavity 24 and ensuring accurate calibration. The pressurized inner cover 7 is provided with an end face sealing groove 73 on its end face. An end face seal 74 is installed within this end face sealing groove 73 and is sealed against the upper surface of the main body 4. The end face seal 74 seals the interior of the surface microphone mounting cavity 24. Since the output wires must be routed through the output wire slot, a wire sealing pin 45 is inserted into the output wire slot 44 to ensure the sealing of the surface microphone mounting cavity 24. Since calibration of the surface microphone 100 must be performed within a sealed cavity, the cavity seal 43, the end face seal 74, and the sealing pin 45 ensure the cavity's sealing during calibration.

[0044] The specific usage process is as follows:

[0045] like Figure 7 As shown, the surface microphone multi-purpose calibration adapter is connected to a conventional calibration device for surface microphone frequency lower limit testing.

[0046] Remove the upper cover 2 by rotation, place the surface microphone 100 into the surface microphone mounting cavity 41 inside the main body 4, extend the signal output line 101 of the surface microphone through the sealing pin 45 to the external measuring amplifier 200, then tighten the upper cover 2, and pressurize the surface microphone 100 into the surface microphone mounting cavity 41 by the pressurized spring 72 at the center of the inner cover 7. At this time, the end face seal 74 on the inner cover 7 is sealed with the surface of the main body 4, and the cavity seal 43 is sealed with the surface of the surface microphone 100, thereby achieving the sealing of the surface microphone fixing cavity. The main microphone 3 is installed into the microphone lower frequency limit calibration system 300, and the lower frequency limit of the surface microphone can be calibrated.

[0047] Specifically, the microphone lower frequency limit calibration system 300 contains a sound source 301 and a cavity 302. During microphone lower frequency limit calibration, the microphone's pressure equalizing port must be exposed to the sound field. This means the microphone's pressure equalizing port must be connected to the cavity. Therefore, during calibration, the main microphone 3 is installed and sealed within the cavity 302 of the microphone lower frequency limit calibration system, while the acoustic coupling cavity 31 within the main microphone 3 is connected to the cavity 302.

[0048] Because the surface microphone multi-purpose calibration adapter has a through-hole 32 in the main microphone body 3, during testing, the sound emitted by the sound source passes through the cavity 302, the acoustic coupling cavity 31, the through-hole 32, and the lower frequency limit calibration sound transmission hole 33, and then to the pressure equalizing hole 102 in the surface microphone. This ensures that the surface microphone's pressure equalizing hole is connected to the acoustic coupling cavity within this fixture. The acoustic coupling cavity volume of 452.2 mm³ in the main body is precisely calculated and designed based on the surface microphone, effectively transmitting sound and ensuring test accuracy. A test signal is sent to the microphone lower frequency limit calibration system 300. This signal passes through the connected cavity 302, the acoustic coupling cavity 31, the through-hole 32, and the lower frequency limit calibration sound transmission hole 33 to calibrate the surface microphone's lower frequency limit.

[0049] Example 2:

[0050] exist Figure 8 In the embodiment shown, a multi-purpose calibration adapter for a surface microphone has a technical solution that is substantially the same as that of embodiment 1, except that it further includes a jacket 9 and a sealing plug 10.

[0051] like Figure 5 、 Figure 6 As shown, the jacket 9 includes an integrally arranged dynamic upper limit calibration connector 11 and a jacket main body 12. The dynamic upper limit calibration connector 11 is arranged in a cylindrical structure, and a high sound pressure transmission cavity 13 is arranged inside the dynamic upper limit calibration connector 11. The jacket main body 12 is an annular structure, and a jacket sealing groove 14 is opened on the inner wall of the jacket main body 12. A jacket seal 15 is arranged inside the jacket sealing groove 14, and the jacket seal 15 is sealed and connected to the outer wall of the main sound conductor 3.

[0052] In order to achieve the accuracy of calibration of the upper limit of the dynamic range of the surface microphone and the sealing of the cavity where the surface microphone is located during the calibration process, a sealing plug 10 is further inserted into the through hole.

[0053] like Figure 9 As shown, the surface microphone multi-purpose calibration adapter is connected to a conventional microphone dynamic range upper limit calibration device 400 for testing the microphone dynamic range upper limit of a surface microphone.

[0054] The upper limit of a microphone's dynamic range refers to the upper limit of the sound pressure level that the microphone can measure. Surface microphones also have the same calibration requirements. The upper limit of the dynamic range of a surface microphone 100 is tested by connecting the multi-purpose surface microphone calibration adapter to a conventional microphone upper limit dynamic range calibration device 400. Specifically, the upper cover 2 is removed by rotating, and the surface microphone 100 is placed into the surface microphone mounting cavity 41 within the main body 4. The signal output line 101 of the surface microphone 100 is extended to the external measurement amplifier 2200 via the sealing pin 45. The upper cover 2 is then tightened. The pressurized spring 72 at the center of the pressurized inner cover 7 pressurizes and secures the surface microphone 100 within the surface microphone mounting cavity 41. At this point, the end face seal 74 on the pressurized inner cover 7 is sealed to the surface of the main body 4, and the cavity seal 43 is sealed to the surface of the surface microphone 100, thereby ensuring the sealing of the surface microphone mounting cavity 24. A sealing plug 10 is inserted into the through-hole 32 to seal the through-hole 32 and block the communication between the lower frequency limit calibration sound transmission hole 33 and the through-hole 32. The main sound transmission element 3 is then installed into the outer shell 12 and sealed to the inner wall of the outer shell 12. The dynamic upper limit calibration connector 11 on the outer shell is then inserted into the microphone dynamic range upper limit calibration device 400. A detection signal is sent to the microphone dynamic range upper limit calibration device 400, generating a high sound pressure. This high sound pressure is then transmitted to the acoustic coupling cavity 31 through the high sound pressure transmission cavity 13 inside the dynamic upper limit calibration connector 11 on the outer shell. The design of the acoustic coupling cavity allows for efficient transmission of the high-pressure sound, which is then transferred to the surface microphone 100 in the cavity of the surface microphone multi-purpose fixture. This allows for calibration of the dynamic range upper limit of the surface microphone 100, achieving high calibration accuracy and convenient operation.

[0055] Example 3:

[0056] exist Figure 10 In the embodiment shown, a multi-purpose calibration adapter for a surface microphone has a technical solution substantially the same as that of embodiment 1, except that it further includes a sealing plug 10 .

[0057] In order to achieve the accuracy of the surface microphone sound calibration and the sealing of the cavity where the surface microphone is located during the calibration process, a sealing plug is further inserted into the through hole 32 .

[0058] like Figure 11 As shown, the surface microphone multi-purpose calibration adapter is connected to a conventional sound calibrator 500 for a sound calibration test of a surface microphone.

[0059] Before each use of the microphone, a sound calibrator is required to calibrate microphones of different sensitivity levels to the same sensitivity. Surface microphones also need to be calibrated before use. Specifically, remove the upper cover 2 by rotating it, place the surface microphone 100 into the surface microphone mounting cavity 41 inside the main body 4, extend the signal output line 101 of the surface microphone 100 to the external measurement amplifier 200 through the sealing pin 45, then tighten the upper cover 2, and pressurize the surface microphone 100 into the surface microphone mounting cavity 41 through the pressurized spring 72 at the center of the inner cover 7. At this time, the end face seal 74 on the inner cover 7 is sealed with the surface of the main body 4, and the cavity seal 43 is sealed with the surface of the surface microphone 100, thereby achieving the sealing of the surface microphone fixing cavity 24. Insert the sealing plug 10 into the through hole 32 to seal the through hole 32 and block the communication between the lower frequency calibration sound transmission hole 33 and the through hole 32. Then the main sound transmitter 3 is installed in the sound calibrator 500 and forms a sealed connection with the inner wall of the sound calibrator 500. Turning on the switch of the sound calibrator 500 can calibrate the surface microphone, which is convenient and practical to operate.

[0060] The multi-purpose surface microphone calibration adapter shown in the above embodiment can be directly connected to the existing microphone lower frequency limit calibration system, microphone dynamic range calibration system and microphone sensitivity calibration system to realize the surface microphone lower frequency limit test, microphone dynamic range upper limit test and sound calibration test without the need to set up special surface microphone calibration equipment. The universality of the calibration equipment between surface microphones and conventional microphones is achieved, and the calibration is convenient, fast and highly accurate, which reduces the cost of manufacturing special surface microphone calibration equipment and greatly improves the calibration efficiency of the microphone calibration industry.

[0061] The method for simultaneously performing a surface microphone calibration lower limit test, a microphone dynamic range upper limit test, and an acoustic calibration test on a surface microphone using the surface microphone multi-purpose calibration adapter described in the above embodiment includes the following steps:

[0062] Step 1: Installing the surface microphone: Remove the upper cover 2 by rotating it, and place the surface microphone 100 into the surface microphone mounting cavity 41 inside the main body 4. Extend the surface microphone's signal output line 101 through the sealing pin 45 and connect it to the external measurement amplifier 200. Then tighten the upper cover 2. The pressurized spring 72 at the center of the pressurized inner cover 7 pressurizes and secures the surface microphone 100 in the surface microphone mounting cavity 41. At this point, the end face seal 74 on the pressurized inner cover 7 is sealed to the surface of the main body 4, and the cavity seal 43 is sealed to the surface of the surface microphone 100.

[0063] Step 2: Surface Microphone Frequency Lower Limit Test: The main microphone 3 assembled in Step 1 is installed into the microphone frequency lower limit calibration system 300 to calibrate the surface microphone's frequency lower limit. Specifically, the main microphone 3 is installed into the cavity 302 of the microphone frequency lower limit calibration system and sealed therewith, and the acoustic coupling cavity 31 inside the main microphone 3 is connected to the cavity 302. A test signal is sent to the microphone frequency lower limit calibration system 300. This signal is transmitted through the connected cavity 302, acoustic coupling cavity 31, through-hole 32, and frequency lower limit calibration sound transmission hole 33 to the pressure equalizing hole 102 on the surface microphone, thereby calibrating the surface microphone's frequency lower limit.

[0064] Step 3: Acoustic Calibration Test of the Surface Microphone: Insert the sealing plug 10 into the through-hole 32 of the main body assembled in Step 1 to seal the through-hole 32 and block the communication between the lower frequency limit calibration sound transmission hole 33 and the through-hole 32. Then, install the main body sound transmission body 3 into the sound calibrator 500 and form a sealed connection between it and the inner wall of the sound calibrator 500. Turn on the switch of the sound calibrator 500 to calibrate the surface microphone.

[0065] Step 4: Testing the upper limit of the dynamic range of the surface microphone: The main microphone 3 assembled in step 3 is placed into the outer shell and sealed with the outer shell. The dynamic upper limit calibration connector 11 on the outer shell is then inserted into the microphone dynamic range upper limit calibration device 400. A detection signal is sent to the microphone dynamic range upper limit calibration device 400, emitting high sound pressure. The high sound pressure is transmitted to the acoustic coupling cavity 31 through the high sound pressure transmission cavity 13 inside the dynamic upper limit calibration connector 11 on the outer shell, thereby calibrating the upper limit of the dynamic range of the surface microphone 100.

[0066] The above calibration method greatly simplifies the calibration method of the surface microphone, and the calibration test can be directly performed by referring to the method of conventional microphones. There is no need to develop a dedicated device for the surface microphone. The calibration test can be performed by connecting the adapter to the conventional microphone calibration device.

[0067] The contents described in the embodiments of this specification are merely an enumeration of the implementation forms of the inventive concept. The protection scope of the inventive type should not be considered as being limited to the specific forms described in the embodiments. The protection scope of the inventive type also extends to equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. A multi-purpose calibration adapter for surface microphones, characterized by: The invention comprises a main body (1) and an upper cover (2) that are movably connected, a sealed surface microphone fixing cavity (24) is formed between the main body (1) and the upper cover (2), an acoustic coupling cavity (31) communicating with the surface microphone fixing cavity (24) and a frequency lower limit calibration sound transmission hole (33) communicating with the surface microphone pressure equalizing hole are provided on the main body (1), and the frequency lower limit calibration sound transmission hole (33) is communicated with the acoustic coupling cavity (31); a pressure spring (72) is provided on the upper cover (2); The main body (1) comprises an integrally arranged main sound transmitting body (3) and a main body base (4); a through hole (32) connected to the acoustic coupling cavity (31) is radially arranged on the main sound transmitting body (3); a frequency lower limit calibration sound transmitting hole (33) is arranged perpendicular to the through hole (32) and connects the through hole (32) and the main body base (4); an output wire groove (44) is opened on the side of the main body base (4) parallel to the through hole (32), and a lead wire sealing pin (45) is inserted into the output wire groove (44).

2. The multi-purpose surface microphone calibration adapter according to claim 1, characterized in that: The cavity volume of the acoustic coupling cavity (31) is 450 mm³ to 455 mm³.

3. The multi-purpose surface microphone calibration adapter according to claim 1, characterized in that: The output line slot (44) is opened on the surface microphone fixing cavity (24).

4. The multi-purpose surface microphone calibration adapter according to claim 1, characterized in that: The main body (1) further includes an integral main body connector (5), the acoustic coupling cavity (31) is arranged along the axis of the main body sound conductor (3), and the axis of the lower frequency limit calibration sound transmission hole (33) is parallel to the axis of the main body sound conductor (3).

5. The multi-purpose surface microphone calibration adapter according to claim 4, characterized in that: A surface microphone mounting cavity (41) is provided inside the main body (4), a sealing cavity (42) is provided at the connection between the surface microphone mounting cavity (41) and the acoustic coupling cavity (31), and a cavity sealing member (43) is provided inside the sealing cavity (42).

6. The multi-purpose surface microphone calibration adapter according to claim 1, characterized in that: The upper cover (2) includes a connecting outer cover body (6) and a pressurized inner cover body (7) arranged coaxially, a cover body outer cavity (8) is formed between the connecting outer cover body (6) and the pressurized inner cover body (7), a cover body inner cavity (71) is provided inside the pressurized inner cover body (7), the pressurized spring (72) is provided at the center of the cover body inner cavity (71), an end face sealing groove (73) is provided on the end face of the pressurized inner cover body (7), and an end face sealing member (74) is provided inside the end face sealing groove (73).

7. The multi-purpose surface microphone calibration adapter according to any one of claims 1 to 6, characterized in that: The invention also includes a jacket (9), wherein the jacket (9) includes an integrally arranged dynamic upper limit calibration connector (11) and a jacket body (12), a high sound pressure transmission cavity (13) is provided inside the dynamic upper limit calibration connector (11), a jacket sealing groove (14) is provided on the inner wall of the jacket body (12), and a jacket sealing member (15) is provided inside the jacket sealing groove (14).

8. The multi-purpose surface microphone calibration adapter according to any one of claims 1 to 6, characterized in that: It also includes a sealing plug (10) for blocking the communication between the lower frequency limit calibration sound transmission hole (33) and the surface microphone pressure equalizing hole.

9. A method for calibrating a surface microphone using the multi-purpose calibration adapter according to any one of claims 1 to 8, characterized in that The following steps are involved: Step 1: Install the surface microphone: Rotate and remove the upper cover (2), place the surface microphone (100) into the surface microphone mounting cavity (41) inside the main body (4), extend the signal output line (101) of the surface microphone through the sealing pin (45) and connect it to the external measurement amplifier (200), then tighten the upper cover (2), and press the surface microphone (100) into the surface microphone mounting cavity (41) through the pressure spring (72) at the center of the pressure inner cover (7). At this time, the end face seal (74) on the pressure inner cover (7) is sealed and connected to the surface of the main body (4), and the cavity seal (43) is sealed and connected to the surface of the surface microphone (100); Step 2: Surface microphone frequency lower limit test: The main microphone body (3) assembled in step 1 is installed into the microphone frequency lower limit calibration system (300), so as to achieve the frequency lower limit calibration of the surface microphone; Step 3: Acoustic calibration test of the surface microphone: insert a sealing plug (10) into the through hole (32) of the main body assembled in step 1 to seal the through hole (32) and block the communication between the lower frequency limit calibration sound transmission hole (33) and the through hole (32). Then, install the main sound transmission body (3) into the sound calibrator (500) and form a sealed connection between the main sound transmission body (3) and the inner wall of the sound calibrator (500). Turn on the switch of the sound calibrator (500) to calibrate the surface microphone. Step 4: Testing the upper limit of the dynamic range of the surface microphone: The main microphone (3) assembled in step 3 is placed in the outer shell and sealed with the outer shell, and then the dynamic upper limit calibration connector (11) on the outer shell is inserted into the upper limit calibration device (400) for the dynamic range of the microphone, and a detection signal is sent to the upper limit calibration device (400) for the dynamic range of the microphone, and a high sound pressure is emitted. The high sound pressure is transmitted to the acoustic coupling cavity (31) through the high sound pressure transmission cavity (13) inside the dynamic upper limit calibration connector (11) on the outer shell, thereby calibrating the upper limit of the dynamic range of the surface microphone (100).

10. The method according to claim 9, characterized in that: In step 2, the main sound transmitter (3) is installed in the cavity (302) of the microphone lower frequency limit calibration system and is sealed therewith, and the acoustic coupling cavity (31) inside the main sound transmitter (3) is connected to the cavity (302); a test signal is sent to the microphone lower frequency limit calibration system (300), and this signal is transmitted to the pressure equalizing hole (102) on the surface microphone through the connected cavity (302), the acoustic coupling cavity (31), the through hole (32), and the lower frequency limit calibration sound transmission hole (33), thereby achieving calibration of the lower frequency limit of the surface microphone.

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