Special electret sensor for heart and lung sound

Abstract

The utility model relates to a heart and lung sound special electret sensor. 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 and 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 and lung sound special electret sensor has remarkable technical advantages in the field of heart and lung sound detection.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to a special electret sensor for heart and lung sounds. Background Art

[0002] With the continuous advancement of technology, vibration sensors play a vital role in many application areas, such as voice transmission, medical health monitoring, and industrial equipment monitoring. In particular, voice transmission and heart and lung sound detection place higher demands on signal capture accuracy and quality. The balance between sensitivity and noise in traditional vibration sensor design has long troubled industry experts. Increased sensitivity in vibration sensors is often accompanied by increased background noise, which results in 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, while reducing noise to improve the SNR, sensitivity is often insufficient, making it impossible to effectively capture the desired weak signals.

[0003] In voice transmission applications, sensors must accurately capture subtle sound changes, especially during human voice interaction. The sensitivity of vibration sensors directly impacts the accuracy of voice recognition systems. In the medical field, detecting heart and lung sounds places extremely high demands on weak and complex physiological signals. The sensor's sensitivity and signal-to-noise ratio directly impact 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. Utility Model Content

[0004] Based on this, it is necessary to provide a special electret sensor for cardiopulmonary sounds to address the problem that the balance between high sensitivity and low noise cannot be achieved, which has become a technical problem that needs to be solved urgently in current vibration sensors.

[0005] A special electret sensor for heart and lung sounds, comprising: a housing, an upper 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 upper cover and the electret capacitor, wherein the electret capacitor is electrically connected to the PCB assembly;

[0006] The electret capacitor includes a diaphragm, a back plate, and an insulating ring installed between the diaphragm and the back plate;

[0007] A first counterweight adjustment piece is fixedly mounted on a side of the diaphragm facing away from the insulating ring, and a second counterweight adjustment piece is fixedly mounted on a side of the first counterweight adjustment piece facing away from the diaphragm, wherein the first counterweight adjustment piece and the second counterweight adjustment piece are made of different materials;

[0008] 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;

[0009] The electret capacitor is used to generate a changing cardiopulmonary sound electrical signal through the vibration of the diaphragm, and the PCB assembly is used to amplify the cardiopulmonary sound electrical signal and provide the amplified cardiopulmonary sound electrical signal to an external circuit for disease diagnosis.

[0010] When the above-mentioned special electret sensor for heart and lung sounds is working, the diaphragm can vibrate under the action of the mechanical vibration signal of the heart and lung sounds, so that the electret capacitor generates a changing heart and lung sound electrical signal, and the back plate can transmit the changing heart and lung sound electrical signal to the PCB assembly, and the PCB assembly can amplify the heart and lung sound electrical signal, so that the external circuit can diagnose the disease based on the amplified heart and lung sound electrical signal. In the related art, the vibration of the diaphragm is very susceptible to interference from high-frequency noise. The diaphragm can be weighted and adjusted by the first and second weight-adjusting plates to block the influence of high-frequency interference on the diaphragm; further, the first and second frequency-adjusting holes can allow sound signals to pass through, so that the diaphragm vibrates; further, if only a single weight-adjusting plate is installed on the diaphragm, when the weight meets the requirements, the depth of the frequency-adjusting hole may not meet the requirements, and when the depth of the frequency-adjusting hole meets the requirements, the weight may not meet the requirements. The first and second weight-adjusting plates can adjust the weight of the diaphragm to block the influence of high-frequency interference on the diaphragm; further, the first and second frequency-adjusting holes can allow sound signals to pass through, so that the diaphragm vibrates; further, if only a single weight-adjusting plate is installed on the diaphragm, when the weight meets the requirements, the depth of the frequency-adjusting hole may not meet the requirements, and when the depth of the frequency-adjusting hole meets the requirements, the weight may not meet the requirements. The plates are made of materials of different densities, so that when adjusting the diaphragm's counterweight, the hole depth can be adjusted at the same time. The hole depth adjustment can further adjust the sound resistance, thereby optimizing the diaphragm's resonant frequency. Furthermore, according to actual needs, at least one second frequency adjustment hole on the second counterweight adjustment plate can be blocked to adjust the number of second frequency adjustment holes. The more second frequency adjustment holes are blocked, the better the low-frequency performance of the special electret sensor for heart and lung sounds. The fewer second frequency adjustment holes are blocked, the better the high-frequency performance of the special electret sensor for heart and lung sounds. This special electret sensor for heart and lung sounds can not only take advantage of the high sensitivity of the electret sensor, but also filter out high-frequency noise interference, and has obvious technical advantages in the field of heart and lung sound detection.

[0011] 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.

[0012] In one embodiment, the diaphragm is circular, and a diaphragm positioning ring is fixedly connected to the edge of the diaphragm.

[0013] In one embodiment, an annular support wall is formed on one side edge of the housing toward the axis of the housing;

[0014] A first copper ring is mounted on the annular support wall, and the diaphragm positioning ring abuts against the first copper ring.

[0015] In one embodiment, a second copper ring is provided between the upper cover and the PCB assembly, and the second copper ring is used to support the upper cover.

[0016] In one embodiment, the back plate is fixedly connected to the PCB assembly, and a third frequency adjustment hole is provided on the back plate.

[0017] In one embodiment, 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 circuit is also used to supply power to the PCB assembly through the wiring through hole, and the tuning hole is used to apply tuning fiber cloth.

[0018] In one embodiment, a field effect transistor is provided on the PCB assembly;

[0019] The gate of the field effect tube 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.

[0020] In one embodiment, the field effect transistor is a junction field effect transistor. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the explosion structure of the special electret sensor for heart and lung sounds of the utility model;

[0022] 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;

[0023] Figure 3 This is another overall structural diagram of the special electret sensor for heart and lung sounds of the utility model.

[0024] Figure 4 for Figure 1 Schematic diagram of the structure of the middle shell;

[0025] Figure 5 for Figure 1 Schematic diagram of the structure of the middle upper cover;

[0026] Figure 6 for Figure 1 A schematic structural diagram of the first counterweight adjustment plate;

[0027] Figure 7 for Figure 1 A schematic structural diagram of the second counterweight adjustment plate;

[0028] Figure 8 for Figure 1 Schematic diagram of the structure of the middle back plate;

[0029] Figure 9 for Figure 1 Schematic diagram of the combined structure of the middle diaphragm, the first counterweight adjustment plate, the second counterweight adjustment plate and the diaphragm positioning ring;

[0030] Figure 10 This is the circuit principle diagram of the special electret sensor for heart and lung sounds of the utility model;

[0031] Among them, 10 is the outer shell, 11 is the annular support wall, 20 is the upper 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 plate, 341 is the first frequency adjustment hole, 35 is the second counterweight adjustment plate, 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 DESCRIPTION

[0032] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of specific embodiments of the present invention is provided in conjunction with the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0033] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time. In contrast, when an element is referred to as being "directly on" another element, there is no intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only."

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of this invention are intended only to describe specific embodiments and are not intended to limit this invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0035] The utility model discloses a special electret sensor for heart and lung sounds.

[0036] like Figures 1 to 3As shown, the special electret sensor for heart and lung sounds includes: a shell 10, an upper cover 20 installed on one side of the shell 10, an electret capacitor 30 installed on the other side of the shell 10, and a PCB assembly 40 installed between the upper cover 20 and the electret capacitor 30, and the electret capacitor 30 is electrically connected to the PCB assembly 40.

[0037] 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 plate 34 is fixedly installed on the side of the diaphragm 31 away from the insulating ring 33, and a second counterweight adjustment plate 35 is fixedly installed on the side of the first counterweight adjustment plate 34 away from the diaphragm 31. The first counterweight adjustment plate 34 and the second counterweight adjustment plate 35 are made of different materials. Preferably, the first counterweight adjustment plate 34 is made of brass and the second counterweight adjustment plate 35 is made of steel.

[0038] The first counterweight adjustment plate 34 is provided with a plurality of first frequency adjustment holes 341, and the second counterweight adjustment plate 35 is provided with a plurality of 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.

[0039] When the above-mentioned special electret sensor for heart and lung sounds is working, the diaphragm can vibrate under the action of the mechanical vibration signal of the heart and lung sounds, so that the electret capacitor generates a changing heart and lung sound electrical signal, and the back plate can transmit the changing heart and lung sound electrical signal to the PCB assembly, and the PCB assembly can amplify the heart and lung sound electrical signal, so that the external circuit can diagnose the disease based on the amplified heart and lung sound electrical signal. In the related art, the vibration of the diaphragm is very susceptible to interference from high-frequency noise. The diaphragm can be weighted and adjusted by the first and second weight-adjusting plates to block the influence of high-frequency interference on the diaphragm; further, the first and second frequency-adjusting holes can allow sound signals to pass through, so that the diaphragm vibrates; further, if only a single weight-adjusting plate is installed on the diaphragm, when the weight meets the requirements, the depth of the frequency-adjusting hole may not meet the requirements, and when the depth of the frequency-adjusting hole meets the requirements, the weight may not meet the requirements. The first and second weight-adjusting plates can adjust the weight of the diaphragm to block the influence of high-frequency interference on the diaphragm; further, the first and second frequency-adjusting holes can allow sound signals to pass through, so that the diaphragm vibrates; further, if only a single weight-adjusting plate is installed on the diaphragm, when the weight meets the requirements, the depth of the frequency-adjusting hole may not meet the requirements, and when the depth of the frequency-adjusting hole meets the requirements, the weight may not meet the requirements. The plates are made of materials of different densities, so that when adjusting the diaphragm's counterweight, the hole depth can be adjusted at the same time. The hole depth adjustment can further adjust the sound resistance, thereby optimizing the diaphragm's resonant frequency. Furthermore, according to actual needs, at least one second frequency adjustment hole on the second counterweight adjustment plate can be blocked to adjust the number of second frequency adjustment holes. The more second frequency adjustment holes are blocked, the better the low-frequency performance of the special electret sensor for heart and lung sounds. The fewer second frequency adjustment holes are blocked, the better the high-frequency performance of the special electret sensor for heart and lung sounds. This special electret sensor for heart and lung sounds can not only take advantage of the high sensitivity of the electret sensor, but also filter out high-frequency noise interference, and has obvious technical advantages in the field of heart and lung sound detection.

[0040] 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 that of the second frequency adjustment hole 351. The alignment of the first frequency adjustment hole 341 with the second frequency adjustment hole 351 allows the sound signal to better act on the diaphragm 31, thereby improving the sensitivity of the diaphragm 31. The smaller area of ​​the first frequency adjustment hole 341 than that of the second frequency adjustment hole 351 reduces the acoustic resistance of the sound signal as it passes from the outside world through the second frequency adjustment hole 351, the first frequency adjustment hole 341, and finally acts on the diaphragm 31, thereby further improving the sensitivity of the diaphragm 31.

[0041] 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 to prevent displacement of the diaphragm 31.

[0042] Furthermore, an annular support wall 11 is formed on one side edge of the housing 10, extending in the direction of the housing 10 axis. A first copper ring 50 is mounted on the annular support wall 11, and the diaphragm positioning ring 11 abuts against the first copper ring 50. The first copper ring 50 supports the diaphragm positioning ring 36, thereby further supporting the diaphragm 31, the first counterweight adjustment plate 34, and the second counterweight adjustment plate 35.

[0043] 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 special electret sensor for heart and lung sounds.

[0044] Furthermore, the back plate 32 is fixedly connected to the PCB assembly 40, and a third frequency adjustment hole 321 is provided on the back plate 32. The third frequency adjustment hole 321 can reduce the squeeze film damping, thereby improving the performance of the special electret sensor for cardiopulmonary sounds. When the size of the special electret sensor for cardiopulmonary sounds is small, the air gap between the back plate 32 and the diaphragm 31 will produce squeeze film damping, which will limit the frequency response bandwidth of the special electret sensor for cardiopulmonary sounds. In order to reduce this squeeze film damping effect, a plurality of third frequency adjustment holes 321 are provided on the back plate 32, thereby reducing the squeeze film damping and improving the frequency response bandwidth of the special electret sensor for cardiopulmonary sounds.

[0045] The upper cover 20 is provided with a wiring through-hole 21, and the PCB assembly 40 is used to connect to an external circuit through the wiring through-hole 21. The external circuit is also used to power the PCB assembly 40 through the wiring through-hole 21. The provision of the wiring through-hole 21 makes it easier to connect the special electret sensor for heart and lung sounds to the external circuit. Furthermore, the upper cover 20 is also provided with a tuning hole 22, which is used to apply a tuning fiber cloth. By controlling the thickness of the tuning fiber cloth, the resonant frequency of the special electret sensor for heart and lung sounds can be further adjusted.

[0046] like Figure 10 As shown, a field effect transistor FET is provided on the PCB assembly 40; the gate of the field effect transistor 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.

[0047] Through the mutual cooperation of the field effect tube FET, the diaphragm 31 and the back plate 32, the special electret sensor for heart and lung sounds can achieve dual-mode output, namely drain output and source output. The sensitivity of the drain output is relatively high, the output signal is strong, but the signal-to-noise ratio is not high; the sensitivity of the source output is relatively low, the operation is stable, but the signal-to-noise ratio is relatively high. The external circuit can control the special electret sensor for heart and lung sounds to perform drain output or source output according to actual needs. When the special electret sensor for heart and lung sounds is controlled to perform drain output, the external circuit connects the second terminal and the third terminal together, and obtains the sensing signal of the special electret sensor for heart and lung sounds through the first terminal; when the special electret sensor for heart and lung sounds is controlled to perform source output, the external circuit no longer connects the second terminal and the third terminal together, and obtains the sensing signal of the special electret sensor for heart and lung sounds through the second terminal.

[0048] Furthermore, the type of the field effect transistor FET can be selected according to actual needs. Preferably, the field effect transistor FET is a junction field effect transistor.

[0049] The utility model also discloses an assembly method of the above-mentioned special electret sensor for heart and lung sounds, comprising:

[0050] Determine an application scenario of the special electret sensor for heart and lung sounds; determine the resonant frequency of the special electret sensor for heart and lung sounds according to the application scenario; seal at least one second frequency adjustment hole on the second counterweight adjustment plate according to the resonant frequency; assemble the second counterweight adjustment plate after the sealing operation, the upper cover after the application operation, the first counterweight adjustment plate, the diaphragm, the insulating ring, the back plate, the outer shell, the upper cover and the PCB assembly into the special electret sensor for heart and lung sounds.

[0051] Furthermore, tuning fiber cloth can be applied to the tuning hole of the upper cover according to the resonant frequency, and the second counterweight adjustment plate after the sealing operation, the upper cover after the application operation, the first counterweight adjustment plate, the diaphragm, the insulating ring, the back plate, the outer shell and the PCB assembly can be assembled into a special electret sensor for cardiopulmonary sounds.

[0052] In the assembly method of the special electret sensor for heart and lung sounds of the utility model, according to different application scenarios of the special electret sensor for heart and lung sounds, the second counterweight adjustment plate and the upper cover are respectively sealed and applied during the assembly stage of the special electret sensor for heart and lung sounds to adjust the resonant frequency of the special electret sensor for heart and lung sounds. The first counterweight adjustment plate, diaphragm, insulating ring, back plate, outer shell and PCB components can be standard parts, so that the special electret sensor for heart and lung sounds can be quickly customized according to the actual use needs of customers, while meeting the requirements of product performance and production efficiency and reducing production costs.

[0053] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned 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.

[0054] The above-described embodiments merely represent several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present utility model patent shall be determined by the appended claims.

Claims

1. A special electret sensor for heart and lung sounds, characterized in that: include: A housing, an upper 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 upper cover and the electret capacitor, the electret capacitor being 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 mounted on a side of the diaphragm facing away from the insulating ring, and a second counterweight adjustment piece is fixedly mounted on a side of the first counterweight adjustment piece facing away from the diaphragm, wherein 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 a changing cardiopulmonary sound electrical signal through the vibration of the diaphragm, and the PCB assembly is used to amplify the cardiopulmonary sound electrical signal and provide the amplified cardiopulmonary sound electrical signal 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 an area of ​​the first frequency adjustment hole is smaller than an 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: An annular support wall is formed on one side edge of the shell toward the axis of the shell; A first copper ring is mounted 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 upper cover and the PCB assembly, and the second copper ring is used to support the upper cover.

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

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 circuit is also used to supply power to the PCB assembly through the wiring through-hole, and the tuning hole is used to apply tuning fiber cloth.

8. The special electret sensor for heart and lung sounds according to claim 7, characterized in that: The PCB assembly is provided with a field effect tube; The gate of the field effect tube 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 tube is a junction field effect tube.

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