Cardiopulmonary sound special electret sensor and assembling method thereof

Abstract

The invention relates to a heart and lung sound special electret sensor and an assembling method thereof. The heart and lung sound special electret sensor comprises a shell, an upper cover, an electret capacitor and a PCB assembly, wherein the electret capacitor is electrically connected with the PCB assembly; the electret capacitor comprises a vibrating diaphragm, a back polar plate and an insulating ring; a first counterweight adjusting sheet is mounted on one side, deviating from the insulating ring, of the vibrating diaphragm; a second counterweight adjusting sheet is mounted on one side, deviating from the vibrating diaphragm, of the first counterweight adjusting sheet; the first counterweight adjusting sheet is provided with a first frequency adjusting hole, and the second counterweight adjusting sheet is provided with a second frequency adjusting hole. The electret capacitor is used for generating changing heart and lung sound electric signals through vibration of the vibrating diaphragm, and the PCB assembly is used for amplifying the heart and lung sound electric signals and providing the amplified heart and lung sound electric signals for an external circuit for disease diagnosis. According to the heart-lung sound special electret sensor, the resonant frequency and the output sensitivity can be adjusted according to the requirements of application scenes, and the heart-lung sound special electret sensor has remarkable technical advantages in the field of heart-lung sound detection.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, and in particular to a special electret sensor for heart and lung sounds and its assembly method. Background Technology

[0002] With the continuous development of technology, vibration sensors play a crucial role in many application fields, such as voice transmission, medical and health monitoring, and industrial equipment monitoring. Especially in fields like voice transmission and cardiopulmonary sound detection, higher demands are placed on the accuracy and quality of signal capture. The balance between sensitivity and noise in the design of traditional vibration sensors has long been a challenge for industry experts. Increasing the sensitivity of vibration sensors is usually accompanied by an increase in background noise, leading to a decrease in the signal-to-noise ratio (SNR), making it impossible for the sensor to provide high-quality signal output in practical applications. Conversely, when noise is reduced to improve the SNR, the sensitivity is often insufficient, failing to effectively capture the required weak signals.

[0003] In voice transmission applications, sensors need to accurately capture subtle changes in sound, especially in human-voice interaction, where the sensitivity of vibration sensors directly affects the accuracy of voice recognition systems. In the medical field, cardiopulmonary sound detection has extremely high requirements for weak and complex physiological signals; the sensitivity and signal-to-noise ratio of the sensor directly affect the accuracy of disease diagnosis. Therefore, achieving a balance between high sensitivity and low noise has become a pressing technical challenge for current vibration sensors. Summary of the Invention

[0004] Therefore, it is necessary to provide a special electret sensor for cardiopulmonary sounds and its assembly method to address the technical challenge of achieving a balance between high sensitivity and low noise, which is currently an urgent problem to be solved in vibration sensors.

[0005] A special electret sensor for heart and lung sounds includes: a housing, a top cover mounted on one side of the housing, an electret capacitor mounted on the other side of the housing, and a PCB assembly mounted between the top cover and the electret capacitor, wherein the electret capacitor is electrically connected to the PCB assembly. The electret capacitor includes a diaphragm, a back plate, and an insulating ring installed between the diaphragm and the back plate; A first counterweight adjustment piece is fixedly installed on the side of the diaphragm away from the insulating ring, and a second counterweight adjustment piece is fixedly installed on the side of the first counterweight adjustment piece away from the diaphragm. The first counterweight adjustment piece and the second counterweight adjustment piece are made of different materials. The first counterweight adjustment plate is provided with a plurality of first frequency adjustment holes, and the second counterweight adjustment plate is provided with a plurality of second frequency adjustment holes; The electret capacitor is used to generate varying cardiopulmonary sound signals through the vibration of the diaphragm, and the PCB assembly is used to amplify the cardiopulmonary sound signals and provide the amplified cardiopulmonary sound signals to an external circuit for disease diagnosis.

[0006] When the aforementioned special electret sensor for heart and lung sounds is working, the diaphragm vibrates under the mechanical vibration signal of the heart and lung sounds, causing the electret capacitor to generate a changing electrical signal for the heart and lung sounds. The backplate transmits this changing electrical signal to the PCB assembly, which amplifies the signal, allowing external circuitry to perform disease diagnosis based on the amplified signal. In related technologies, the diaphragm vibration is highly susceptible to high-frequency noise interference. The first and second counterweight adjustment plates can be used to adjust the diaphragm's weight, blocking the impact of high-frequency interference. Furthermore, the first and second frequency adjustment holes allow sound signals to pass through, causing the diaphragm to vibrate. However, if only a single counterweight adjustment plate is installed on the diaphragm, the depth of the frequency adjustment hole may not meet the requirements when the weight is sufficient, and vice versa. The first and second counterweight adjustment plates... The two plates are made of materials with different densities, allowing for adjustment of the aperture depth while adjusting the diaphragm's counterweight. Aperture depth adjustment further modulates the acoustic impedance, thereby optimizing the diaphragm's resonant frequency. Furthermore, at least one second frequency adjustment aperture on the second counterweight adjustment plate can be blocked as needed to adjust the number of second frequency adjustment apertures. The more second frequency adjustment apertures blocked, the better the low-frequency performance of this special electret sensor for heart and lung sounds; the fewer second frequency adjustment apertures blocked, the better the high-frequency performance. This special electret sensor for heart and lung sounds leverages the high sensitivity of electret sensors while filtering out high-frequency noise interference, giving it a significant technological advantage in the field of heart and lung sound detection.

[0007] In one embodiment, the first frequency adjustment hole is aligned with the second frequency adjustment hole, and the area of ​​the first frequency adjustment hole is smaller than the area of ​​the second frequency adjustment hole.

[0008] In one embodiment, the diaphragm is circular, and a diaphragm positioning ring is fixedly connected to the edge of the diaphragm.

[0009] In one embodiment, a ring-shaped support wall is formed on one side edge of the housing in the direction of the housing axis; A first copper ring is installed on the annular support wall, and the diaphragm positioning ring abuts against the first copper ring.

[0010] In one embodiment, a second copper ring is provided between the top cover and the PCB assembly, the second copper ring being used to support the top cover.

[0011] In one embodiment, the back electrode plate is fixedly connected to the PCB assembly, and the back electrode plate is provided with a third frequency adjustment hole.

[0012] In one embodiment, the top cover is provided with a wiring through hole and a tuning hole, the PCB assembly is used to connect the external circuit through the wiring through hole; the external circuit is also used to supply power to the PCB assembly through the wiring through hole, and the tuning hole is used to attach tuning fiber cloth.

[0013] In one embodiment, the PCB assembly is provided with a field-effect transistor; The gate of the field-effect transistor is connected to the back plate, the drain is connected to the first terminal of the external circuit, the source is connected to the second terminal of the external circuit, and the diaphragm is connected to the third terminal of the external circuit.

[0014] In one embodiment, the field-effect transistor is a junction field-effect transistor.

[0015] A method for assembling the aforementioned special electret sensor for heart and lung sounds includes: Determine the application scenarios for the special electret sensor for heart and lung sounds; The resonant frequency of the special electret sensor for heart and lung sounds is determined according to the application scenario. At least one second frequency adjustment hole on the second counterweight adjustment piece is blocked according to the resonant frequency; The second counterweight adjustment piece after the sealing operation is assembled with the first counterweight adjustment piece, the diaphragm, the insulating ring, the back electrode plate, the outer shell, the top cover and the PCB assembly to form the special electret sensor for heart and lung sounds. Attached Figure Description

[0016] Figure 1 This is an exploded structural diagram of the special electret sensor for heart and lung sounds of the present invention; Figure 2 This is a schematic diagram of the overall structure of the special electret sensor for heart and lung sounds of the present invention; Figure 3 This is another overall structural schematic diagram of the special electret sensor for heart and lung sounds of the present invention. Figure 4 for Figure 1 Schematic diagram of the inner and outer shell structure; Figure 5 for Figure 1 Schematic diagram of the upper and middle covers; Figure 6 for Figure 1 A schematic diagram of the structure of the first counterweight adjustment piece; Figure 7 for Figure 1 A schematic diagram of the structure of the second counterweight adjustment plate; Figure 8 for Figure 1 Schematic diagram of the structure of the middle back electrode plate; Figure 9 for Figure 1 A schematic diagram of the combined structure of the central diaphragm, the first counterweight adjustment plate, the second counterweight adjustment plate, and the diaphragm positioning ring; Figure 10 This is a circuit diagram of the special electret sensor for heart and lung sounds of the present invention; Among them, 10 is the outer shell, 11 is the annular support wall, 20 is the top cover, 21 is the wiring through hole, 22 is the tuning hole, 30 is the electret capacitor, 31 is the diaphragm, 32 is the back plate, 321 is the third frequency adjustment hole, 33 is the insulating ring, 34 is the first counterweight adjustment piece, 341 is the first frequency adjustment hole, 35 is the second counterweight adjustment piece, 351 is the second frequency adjustment hole, 36 is the diaphragm positioning ring, 40 is the PCB assembly, 50 is the first copper ring, and 60 is the second copper ring. Detailed Implementation

[0017] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0018] It should be noted that when an element is said to be "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is said to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. Conversely, when an element is said to be "directly on" another element, there is no intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0020] This invention discloses a special electret sensor for heart and lung sounds and its assembly method.

[0021] like Figures 1 to 3 As shown, the special electret sensor for heart and lung sounds includes: a housing 10, a top cover 20 mounted on one side of the housing 10, an electret capacitor 30 mounted on the other side of the housing 10, and a PCB assembly 40 mounted between the top cover 20 and the electret capacitor 30. The electret capacitor 30 and the PCB assembly 40 are electrically connected.

[0022] The electret capacitor 30 includes a diaphragm 31, a back plate 32, and an insulating ring 33 installed between the diaphragm 31 and the back plate 32. A first counterweight adjustment piece 34 is fixedly installed on the side of the diaphragm 31 away from the insulating ring 33, and a second counterweight adjustment piece 35 is fixedly installed on the side of the first counterweight adjustment piece 34 away from the diaphragm 31. The first counterweight adjustment piece 34 and the second counterweight adjustment piece 35 are made of different materials. Preferably, the first counterweight adjustment piece 34 is made of brass, and the second counterweight adjustment piece 35 is made of steel.

[0023] The first counterweight adjustment plate 34 is provided with multiple first frequency adjustment holes 341, and the second counterweight adjustment plate 35 is provided with multiple second frequency adjustment holes 351; the electret capacitor 30 is used to generate a changing cardiopulmonary sound electrical signal through the vibration of the diaphragm 31, and the PCB assembly 40 is used to amplify the cardiopulmonary sound electrical signal and provide the amplified cardiopulmonary sound electrical signal to an external circuit for disease diagnosis.

[0024] When the aforementioned special electret sensor for heart and lung sounds is working, the diaphragm vibrates under the mechanical vibration signal of the heart and lung sounds, causing the electret capacitor to generate a changing electrical signal for the heart and lung sounds. The backplate transmits this changing electrical signal to the PCB assembly, which amplifies the signal, allowing external circuitry to perform disease diagnosis based on the amplified signal. In related technologies, the diaphragm vibration is highly susceptible to high-frequency noise interference. The first and second counterweight adjustment plates can be used to adjust the diaphragm's weight, blocking the impact of high-frequency interference. Furthermore, the first and second frequency adjustment holes allow sound signals to pass through, causing the diaphragm to vibrate. However, if only a single counterweight adjustment plate is installed on the diaphragm, the depth of the frequency adjustment hole may not meet the requirements when the weight is sufficient, and vice versa. The first and second counterweight adjustment plates... The two plates are made of materials with different densities, allowing for adjustment of the aperture depth while adjusting the diaphragm's counterweight. Aperture depth adjustment further modulates the acoustic impedance, thereby optimizing the diaphragm's resonant frequency. Furthermore, at least one second frequency adjustment aperture on the second counterweight adjustment plate can be blocked as needed to adjust the number of second frequency adjustment apertures. The more second frequency adjustment apertures blocked, the better the low-frequency performance of this special electret sensor for heart and lung sounds; the fewer second frequency adjustment apertures blocked, the better the high-frequency performance. This special electret sensor for heart and lung sounds leverages the high sensitivity of electret sensors while filtering out high-frequency noise interference, giving it a significant technological advantage in the field of heart and lung sound detection.

[0025] In this configuration, the first frequency adjustment hole 341 is aligned with the second frequency adjustment hole 351, and the area of ​​the first frequency adjustment hole 341 is smaller than the area of ​​the second frequency adjustment hole 351. This alignment allows the sound signal to act more effectively on the diaphragm 31, improving its sensitivity. The smaller area of ​​the first frequency adjustment hole 341 reduces the acoustic impedance as the sound signal travels from the outside through the second frequency adjustment hole 351 and the first frequency adjustment hole 341 before finally acting on the diaphragm 31, further enhancing its sensitivity.

[0026] like Figures 4 to 9 As shown, the diaphragm 31 is circular, and a diaphragm positioning ring 36 is fixedly connected to the edge of the diaphragm 31. The diaphragm positioning ring 36 fixes the diaphragm 31 and prevents the diaphragm 31 from shifting.

[0027] Furthermore, an annular support wall 11 is formed on one side edge of the outer casing 10 in the direction of the axial direction of the outer casing 10. A first copper ring 50 is installed on the annular support wall 11, and the diaphragm positioning ring 11 abuts against the first copper ring 50. The first copper ring 50 can support the diaphragm positioning ring 36, thereby further supporting the diaphragm 31, the first counterweight adjustment plate 34, and the second counterweight adjustment plate 35.

[0028] Furthermore, a second copper ring 60 is provided between the upper cover 20 and the PCB assembly 40, and the second copper ring 60 is used to support the upper cover 20. The second copper ring 60 makes the installation of the upper cover 20 more stable, thereby enhancing the structural stability of the cardiopulmonary sound electret sensor.

[0029] Furthermore, the back electrode plate 32 is fixedly connected to the PCB assembly 40, and the back electrode plate 32 is provided with a third frequency adjustment hole 321. The third frequency adjustment hole 321 can reduce the pressure damping of the diaphragm, thereby improving the performance of the cardiopulmonary sound electret sensor. When the size of the cardiopulmonary sound electret sensor is small, the air gap between the back electrode plate 32 and the diaphragm 31 will generate pressure damping, which will limit the frequency response bandwidth of the cardiopulmonary sound electret sensor. In order to reduce this pressure damping effect, multiple third frequency adjustment holes 321 are provided on the back electrode plate 32, thereby reducing the pressure damping and improving the frequency response bandwidth of the cardiopulmonary sound electret sensor.

[0030] The upper cover 20 has a wiring through-hole 21, through which the PCB assembly 40 connects to an external circuit. The external circuit also supplies power to the PCB assembly 40 through the wiring through-hole 21. The wiring through-hole 21 facilitates the connection between the cardiopulmonary sound electret sensor and the external circuit. Furthermore, the upper cover 20 also has a tuning hole 22 for attaching a tuning fiber cloth. By controlling the thickness of the tuning fiber cloth, the resonant frequency of the cardiopulmonary sound electret sensor can be further adjusted.

[0031] like Figure 10 As shown, a field-effect transistor (FET) is provided on the PCB assembly 40; the gate of the FET is connected to the back plate 32, the drain is connected to the first terminal of the external circuit, the source is connected to the second terminal of the external circuit, and the diaphragm 31 is connected to the third terminal of the external circuit.

[0032] Through the interaction of the field-effect transistor (FET), diaphragm 31, and back electrode plate 32, this special electret sensor for heart and lung sounds can achieve dual-mode output: drain output and source output. Drain output has higher sensitivity and a stronger output signal, but a lower signal-to-noise ratio (SNR); source output has lower sensitivity, more stable operation, but a higher SNR. The external circuit can control the special electret sensor for heart and lung sounds to output either through drain or source as needed. When controlling the sensor for drain output, the external circuit connects the second and third terminals together, and obtains the sensor signal through the first terminal. When controlling the sensor for source output, the external circuit does not connect the second and third terminals together, and obtains the sensor signal through the second terminal.

[0033] Furthermore, the type of field-effect transistor (FET) can be selected according to actual needs. Preferably, the FET is a junction field-effect transistor (JFET).

[0034] This invention also discloses an assembly method for the above-mentioned special electret sensor for heart and lung sounds, comprising: The application scenario of the special electret sensor for heart and lung sounds is determined; the resonant frequency of the special electret sensor for heart and lung sounds is determined according to the application scenario; at least one second frequency adjustment hole on the second counterweight adjustment piece is blocked according to the resonant frequency; the second counterweight adjustment piece after the blocking operation, the top cover after the application operation, the first counterweight adjustment piece, the diaphragm, the insulating ring, the back electrode plate, the outer shell, the top cover and the PCB assembly are assembled into the special electret sensor for heart and lung sounds.

[0035] Furthermore, a tuning fiber cloth can be applied to the tuning hole of the top cover according to the resonant frequency. The second counterweight adjustment piece after the sealing operation, the top cover after the application operation, the first counterweight adjustment piece, the diaphragm, the insulating ring, the back electrode plate, the shell and the PCB assembly are then assembled into a special electret sensor for heart and lung sounds.

[0036] In the assembly method of the special electret sensor for cardiopulmonary sounds of the present invention, depending on the different application scenarios of the special electret sensor for cardiopulmonary sounds, the second counterweight adjustment plate and the top cover are respectively sealed and applied during the assembly stage of the special electret sensor for cardiopulmonary sounds to adjust the resonant frequency of the special electret sensor for cardiopulmonary sounds. The first counterweight adjustment plate, diaphragm, insulating ring, back electrode plate, shell and PCB assembly can be made of standard parts, so that the special electret sensor for cardiopulmonary sounds can be quickly customized according to the actual needs of customers, while meeting the requirements of product performance and production efficiency, and reducing production costs.

[0037] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0038] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A special electret sensor for heart and lung sounds, characterized in that, include: The enclosure, a top cover mounted on one side of the enclosure, an electret capacitor mounted on the other side of the enclosure, and a PCB assembly mounted between the top cover and the electret capacitor, wherein the electret capacitor is electrically connected to the PCB assembly; The electret capacitor includes a diaphragm, a back plate, and an insulating ring installed between the diaphragm and the back plate; A first counterweight adjustment piece is fixedly installed on the side of the diaphragm away from the insulating ring, and a second counterweight adjustment piece is fixedly installed on the side of the first counterweight adjustment piece away from the diaphragm. The first counterweight adjustment piece and the second counterweight adjustment piece are made of different materials. The first counterweight adjustment plate is provided with a plurality of first frequency adjustment holes, and the second counterweight adjustment plate is provided with a plurality of second frequency adjustment holes; The electret capacitor is used to generate varying cardiopulmonary sound signals through the vibration of the diaphragm, and the PCB assembly is used to amplify the cardiopulmonary sound signals and provide the amplified cardiopulmonary sound signals to an external circuit for disease diagnosis.

2. The special electret sensor for heart and lung sounds according to claim 1, characterized in that, The first frequency adjustment hole is aligned with the second frequency adjustment hole, and the area of ​​the first frequency adjustment hole is smaller than the area of ​​the second frequency adjustment hole.

3. The special electret sensor for heart and lung sounds according to claim 1 or 2, characterized in that, The diaphragm is circular, and a diaphragm positioning ring is fixedly connected to the edge of the diaphragm.

4. The special electret sensor for heart and lung sounds according to claim 3, characterized in that, One edge of the outer casing has an annular support wall formed in the direction of the outer casing axis; A first copper ring is installed on the annular support wall, and the diaphragm positioning ring abuts against the first copper ring.

5. The special electret sensor for heart and lung sounds according to claim 4, characterized in that, A second copper ring is provided between the top cover and the PCB assembly, and the second copper ring is used to support the top cover.

6. The special electret sensor for heart and lung sounds according to claim 5, characterized in that, The back electrode plate is fixedly connected to the PCB assembly, and the back electrode plate is provided with a third frequency adjustment hole.

7. The special electret sensor for heart and lung sounds according to claim 6, characterized in that, The upper cover is provided with a wiring through hole and a tuning hole, and the PCB assembly is used to connect the external circuit through the wiring through hole; The external circuitry is also used to power the PCB assembly through the wiring through-hole, and the tuning hole is used to attach tuning fiber cloth.

8. The special electret sensor for heart and lung sounds according to claim 7, characterized in that, The PCB assembly is equipped with a field-effect transistor; The gate of the field-effect transistor is connected to the back plate, the drain is connected to the first terminal of the external circuit, the source is connected to the second terminal of the external circuit, and the diaphragm is connected to the third terminal of the external circuit.

9. The special electret sensor for heart and lung sounds according to claim 8, characterized in that, The field-effect transistor is a junction field-effect transistor.

10. A method for assembling a special electret sensor for heart and lung sounds according to any one of claims 1 to 9, characterized in that, include: Determine the application scenarios for the special electret sensor for heart and lung sounds; The resonant frequency of the special electret sensor for heart and lung sounds is determined according to the application scenario. At least one second frequency adjustment hole on the second counterweight adjustment piece is blocked according to the resonant frequency; The second counterweight adjustment piece after the sealing operation is assembled with the first counterweight adjustment piece, the diaphragm, the insulating ring, the back electrode plate, the outer shell, the top cover and the PCB assembly to form the special electret sensor for heart and lung sounds.

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