Electronic stethoscope pickup cavity based on electret microphone and electronic stethoscope

Abstract

The present invention provides an electronic stethoscope pickup cavity based on an electret microphone, which includes a stethoscope head base, a stethoscope head cover, a diaphragm, and a stethoscope diaphragm fixing ring, wherein an electret microphone is arranged between the stethoscope head cover and the diaphragm, and the electret microphone includes a microphone head, the front of the microphone head is arranged toward the diaphragm, and the wire on the back of the microphone head passes through the stethoscope head to the stethoscope head base through the through hole in the middle of the stethoscope head, and a wire pressing plate is also arranged on the back of the stethoscope head, and a wire pressing channel is arranged inside the wire pressing plate, and the wire is fixed by the wire pressing channel in conjunction with the wire pressing plate and the stethoscope head base. The microphone head is bonded to the stethoscope head by using back glue, and the wire on the back of the microphone head is fixed for a second time by using the wire pressing plate, so as to avoid the displacement of the microphone head during the movement of the electronic stethoscope, which causes environmental noise. The design purpose is to improve the signal-to-noise ratio of the stethoscope in collecting human heart sounds and respiratory sounds, and reduce the interference of environmental noise.

Description

Technical Field

[0001] The invention relates to the field of electronic stethoscopes, and in particular to an electronic stethoscope pickup cavity based on an electret microphone and an electronic stethoscope. Background Art

[0002] Electronic stethoscopes can play an important role in the digital medical era. Through the sound pickup sensor, the human body's heart sounds, breathing sounds, bowel sounds, etc. can be collected and converted into data signals for easy storage and intelligent analysis. The sound pickup sensor is the key to the normal use of electronic stethoscopes. At present, the sensors used in electronic stethoscopes usually include piezoelectric ceramic sensors, piezoelectric film sensors, capacitive sensors, and microphone sensors. Among them, microphone sensors have the best cost performance, but at the same time, due to the multi-directional nature of sound pickup, microphone sensors are easily interfered by environmental noise, which has a great impact on the normal use of the stethoscope. Therefore, the design of the sound pickup cavity using the microphone solution is very critical. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] The problem to be solved by the present invention is to shield the environmental noise collected by the stationary microphone by optimizing the internal structure of the electronic stethoscope pickup cavity, so as to improve the efficiency of collecting the heart sounds and breathing sounds of the human body.

[0005] (II) Technical solution

[0006] One purpose of the present invention is to design an electronic stethoscope pickup cavity based on an electret microphone, which includes a stethoscope base, a stethoscope cover, a diaphragm, and a diaphragm fixing ring, wherein an electret microphone is arranged between the stethoscope cover and the diaphragm, and the electret microphone includes a microphone head, the front of the microphone head is arranged toward the diaphragm, and the wire on the back of the microphone head passes through the stethoscope head to the stethoscope head base through a through hole in the middle of the stethoscope head. A wire pressing plate is also arranged on the back of the stethoscope head, and a wire pressing channel is arranged inside the wire pressing plate. The wire is fixed by using the wire pressing channel in combination with the fixed connection between the wire pressing plate and the stethoscope head base.

[0007] Furthermore, the wire pressing channel of the wire pressing plate extends outwardly along the central axis of the wire pressing plate to the edge of the wire pressing plate.

[0008] Furthermore, two wires are arranged on the back of a microphone, and there is one wire pressing channel on the wire pressing plate, and one channel accommodates two wires.

[0009] Furthermore, two wires are arranged on the back of a microphone head, and there are two wire pressing channels on the wire pressing plate, and one channel accommodates one wire.

[0010] Furthermore, the back of the microphone is attached to the listening head through adhesive, and the head of the microphone is provided with a microphone cover.

[0011] Furthermore, the base of the stethoscope head is in the shape of a trumpet, the tail of which is sealed by a disc, a fixing hole and a wire through hole are left in the middle of the disc, and a card slot is provided at the head portion, which is buckled and connected to the stethoscope head cover.

[0012] Furthermore, a diaphragm is provided at the front end of the earphone head cover, and the diaphragm is fixed by the cooperation between the earphone membrane fixing ring and the earphone head cover.

[0013] Furthermore, the membrane is formed into an inwardly concave structure through a vacuum forming process, and the depth of the inward concave structure is 1.6-2.0 mm.

[0014] Furthermore, the inward depression depth of the diaphragm is 1.8 mm.

[0015] Another object of the present invention is to design an electronic stethoscope based on an electret microphone, which includes the electronic stethoscope pickup cavity and the electronic stethoscope grip, the electronic stethoscope grip includes a shell, the shell interior includes a display module for displaying auscultation data, a processing module for processing and converting auscultation data, a power supply module for supplying energy, and an operation module for providing electronic stethoscope operation.

[0016] (III) Beneficial effects

[0017] The electronic stethoscope pickup cavity provided by the present invention adopts an electret microphone to collect information. The electret microphone has a cost-effective advantage. In order to improve the accuracy of the microphone in collecting sound, the fixing method of the electret microphone in the electronic stethoscope pickup cavity is improved. The microphone head is bonded to the stethoscope head with adhesive, and the wire on the back of the microphone head is fixed for a second time with a wire pressing plate, thereby avoiding the displacement of the microphone head during the movement of the electronic stethoscope to cause environmental noise.

[0018] Secondly, in order to reduce the impact of environmental noise collected by the microphone, the structure of the diaphragm in the pickup cavity of the electronic stethoscope is improved. The traditional diaphragm is a single plane, and the edge of the diaphragm can be pressed onto the stethoscope head cover using a diaphragm fixing ring. In this application, the diaphragm is designed to be an inwardly recessed structure, so that the edge of the diaphragm fits more closely with the edge of the stethoscope head cover, and the internal space of the pickup cavity formed by the diaphragm and the stethoscope head base is increased. At the same time, the vibration of the sound collected by the diaphragm is more consistent with the vibration of the microphone head. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of an electronic stethoscope based on an electret microphone provided by the present invention;

[0020] Figure 2 A schematic diagram of a stethoscope base body in a pickup cavity of an electronic stethoscope based on an electret microphone provided by the present invention;

[0021] Figure 3A cross-sectional view of a stethoscope base body in a pickup cavity of an electronic stethoscope based on an electret microphone provided by the present invention;

[0022] Figure 4 A schematic diagram of a listening head cover in a sound pickup cavity of an electronic stethoscope based on an electret microphone provided by the present invention;

[0023] Figure 5 A cross-sectional view of a stethoscope head cover in a sound pickup cavity of an electronic stethoscope based on an electret microphone provided by the present invention;

[0024] Figure 6 A schematic diagram of a wire pressing plate in a pickup cavity of an electronic stethoscope based on an electret microphone provided by the present invention;

[0025] Figure 7 A schematic diagram of a diaphragm in a sound pickup cavity of an electronic stethoscope based on an electret microphone provided by the present invention;

[0026] Figure 8 A top view of a diaphragm in a pickup cavity of an electronic stethoscope based on an electret microphone provided by the present invention;

[0027] Fig. 9 A schematic diagram of an auditory membrane fixing ring in a sound pickup cavity of an electronic stethoscope based on an electret microphone provided by the present invention;

[0028] Fig.10 A comparison chart of the signal-to-noise ratio of heart sounds collected by an electronic stethoscope based on an electret microphone provided by the present invention and a traditional stethoscope;

[0029] Fig.11 A comparison chart of the signal-to-noise ratio of respiratory sounds collected by an electronic stethoscope based on an electret microphone provided by the present invention and a traditional stethoscope. DETAILED DESCRIPTION

[0030] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0031] The present application provides an electronic stethoscope pickup cavity based on an electret microphone, wherein the pickup cavity 100 includes a stethoscope base 1, a stethoscope cover 2, a diaphragm 3, and a stethoscope fixing ring 4.

[0032] The stethoscope base 1 is horn-shaped, and the tail is sealed by a disc 11. A fixing hole 12 and a wire through hole 13 are left in the middle of the disc 11. A card slot is provided on the head, which is snap-connected with the stethoscope cover 2. The fixing hole 12 on the disc 11 is eccentrically designed and is a round hole, which is convenient for the stethoscope base 1 to be fixed to the electronic stethoscope grip 200 by bolts, and the wire through hole 13 is anisotropically designed, and its cross-section is a square with rounded corners at the top and right angles at the bottom, and the cross-sectional area of ​​the wire through hole 13 is slightly larger than the fixing hole. At the same time, the disc 11 at the tail of the stethoscope base 1 is tilted at a certain angle to the stethoscope cover 2, and the angle is 10-30°, preferably 13°. The central axis of the stethoscope cover 2 just passes through the wire through hole 13. In order to facilitate the installation of the stethoscope head base 1 and the electronic stethoscope grip 200, the stethoscope head base 1 is further extended outward at the wire through hole to form a hook 14, and the hook 14 corresponds to the grip slot of the grip.

[0033] The head cover 2 is mainly used to buckle with the head base 1. A plurality of buckles are arranged on the edge of the head of the head base 1, and a slot matching the buckle of the head of the head base 1 is arranged on the edge of the head cover 2. The two cooperate to achieve a fixed connection between the two. At the same time, a countersunk through hole 21 is arranged in the middle of the head cover 2. The countersunk through hole 21 is mainly used to allow the wire on the back of the microphone head 6 in the electret microphone to pass through. At the same time, the back of the microphone head 6 is attached to the inner wall of the countersunk through hole 21 through the back glue, and the wire passes through the countersunk through hole 21. The head cover 2 is also provided with an arc-shaped inner concave surface 22 facing the diaphragm 3, and the arc-shaped inner concave surface 22 adopts a second-order concave, that is, the inner concave angle of the outermost inner concave surface is smaller than the inner concave angle of the inner concave surface. The pickup cavity 100 is formed between the diaphragm 3 and the head cover 2. Through this special design, the interference of external environmental noise is greatly reduced, and the effectiveness of sound collection is improved.

[0034] The wire pressing plate 5 is arranged on the back of the head cover 2, and is specially used to fix the wire on the back of the microphone 6. Through a large amount of experimental data, it is found that the movement of the wire on the back of the microphone 6 will seriously affect the readiness of collecting sound. For this reason, it is necessary to specially fix the wire on the back of the microphone 6, and a wire pressing channel 51 is arranged on the wire pressing plate 5. The wire pressing channel 51 extends outward in a straight line along the center of the wire pressing plate 5 to form a groove. The cross section of the groove is slightly smaller than the cross section of two wires placed side by side or slightly smaller than the cross section of a single wire, ensuring that the wire pressing plate 5 holds the wire tightly against the back of the head cover 2. When the cross section of the groove is slightly smaller than the cross section of two wires placed side by side, the number of wire pressing channels 51 is 1, and when the cross section of the groove is slightly smaller than the cross section of a single wire, the number of wire pressing channels 51 is 2. The wire pressing plate 5 is a circular plate, and in addition to the groove extending outward in a straight line from the center, there are also pressing plate fixing holes 52, and the two pressing plate fixing holes 52 are symmetrically distributed. The head cover 2 is also provided with bolt holes with internal threads at the positions corresponding to the pressing plate fixing holes 52, so that the head cover 2 and the wire pressing plate 5 are fixedly connected by bolts. At the same time, the microphone part is protected again during the assembly of the microphone, that is, a microphone cover is set to wrap the microphone to prevent dust, water stains, etc. from affecting the microphone collection.

[0035] The diaphragm 3 is arranged at the front end of the earphone head cover 2, and the diaphragm fixing ring 4 cooperates with the earphone head cover 2 to fix the diaphragm 3. The diaphragm 3 is formed into an inwardly concave structure by the vacuum forming process. The diaphragm 3 is generally in the shape of a disk 11. The inward concave structure makes its edge step-shaped. The step-shaped transition is rounded, and the depth of the entire inward concave is 1.6-2.0mm. Preferably, the depth of the inward concave of the diaphragm 3 is 1.8mm. Since the diaphragm 3 adopts an inwardly concave structure, the earphone head cover 2 needs to be provided with a convex structure matching the inward concave structure at its edge. The entire convex structure is in a circular ring shape and adopts a rounded transition to avoid the convex structure of the earphone head cover 2 being too sharp and causing damage to the diaphragm 3.

[0036] In addition to the raised structure of the head cover 2, the present application also provides a raised structure on the diaphragm fixing ring 4, and uses its raised structure to press the stepped outer edge of the diaphragm 3. The inner wall of the diaphragm fixing ring 4 is also provided with a plurality of buckles, which are connected to the slots on the head cover 2 through the buckles, thereby playing the role of fixing the diaphragm 3.

[0037] Another technical solution provided by the present application is an electronic stethoscope based on an electret microphone, which includes the electronic stethoscope pickup cavity 100 and the electronic stethoscope grip 200, wherein the electronic stethoscope grip 200 includes a shell, and the shell includes a display module for displaying auscultation data, a processing module for processing and converting auscultation data, a power supply module for supplying energy, and an operation module for providing electronic stethoscope operation.

[0038] The housing includes an upper shell 211 and a lower shell 212. An operation module, i.e., a plurality of sets of buttons, is arranged on the upper shell 211. The buttons of the plurality of sets of buttons 251 are exposed outside the upper shell 211 through the hollow part on the upper shell 211, which is convenient for users to operate. The outer part of the upper shell 211 is attached with a transparent sheet 260 except for the button position. A processing module is arranged between the upper shell 211 and the lower shell 212. The processing module adopts a multi-layer PCB printed board, and a display module and an operation module are embedded on the PCB printed board. The display module adopts LED, OLED, LCD, min-LCD or other forms of display screens for presentation. A display screen backing foam 221 is arranged outside the display screen to ensure its tightness with the upper shell 211. Bolt holes for fixing it inside the upper shell 211 are arranged on the multi-layer PCB printed board 231. At the same time, a power module is embedded inside the lower shell 212. The power source can be a variety of forms of batteries 241, but must meet the rechargeable characteristics, such as lithium phosphate battery packs or ternary lithium battery packs. The power supply wire on the microphone 6 passes through the through hole on the lower shell 212 and is connected to the battery. The PCB printed board is also connected to the power supply through various forms of wires to ensure the energy requirements of the processing module, the display module, and the operating module.

[0039] In addition, the electronic stethoscope grip 200 may be provided with an external connection port 271 for connecting an earphone or for data transmission or energy transmission. The external connection port 271 may be a 3.5 mm earphone jack or a multi-standard USB interface.

[0040] The electronic stethoscope provided by the present invention was tested with a traditional stethoscope to collect heart sound data and respiratory sound data respectively. The specific data are as follows:

[0041] Comparison of signal-to-noise ratio of human heart sound data collection: see Fig.10 ,in Fig.10 The data displayed above are the heart sound data collected by a traditional stethoscope (the microphone is placed in the hose), and the data displayed below are the heart sound data collected by the electronic stethoscope provided by the present invention. It can be seen that the signal-to-noise ratio is significantly improved.

[0042] Comparison of signal-to-noise ratio of human breathing sound data: see Fig.11 ,in Fig.11 The upper part shows the respiratory sound data collected by a traditional stethoscope (the microphone is placed in the hose), and the lower part shows the respiratory sound data collected by the pickup cavity designed by the invention. It can be seen that the signal-to-noise ratio is significantly improved.

[0043] In summary, the above-mentioned embodiments are not limitative embodiments of the present invention, and any modifications or equivalent variations made by those skilled in the art on the basis of the essential contents of the present invention are within the technical scope of the present invention.

Claims

1. An electronic stethoscope pickup cavity based on an electret microphone, comprising a stethoscope head base, a stethoscope head cover, a diaphragm, and a stethoscope membrane fixing ring, characterized in that: A stationary microphone is arranged between the head cover and the diaphragm. The stationary microphone includes a microphone head. The front of the microphone head is arranged toward the diaphragm. The wire on the back of the microphone head passes through the through hole in the middle of the head to the head base. A wire pressing plate is also arranged on the back of the head. A wire pressing channel is arranged inside the wire pressing plate. The wire is fixed by the wire pressing channel in combination with the fixed connection between the wire pressing plate and the head base. The back of the microphone is attached to the listening head through adhesive, and the head of the microphone is provided with a microphone cover; A diaphragm is arranged at the front end of the earphone cover, and the diaphragm is fixed by the cooperation between the earphone diaphragm fixing ring and the earphone cover; The membrane is formed into an inwardly concave structure through a vacuum forming process.

2. The electronic stethoscope pickup cavity based on an electret microphone according to claim 1, characterized in that: The wire pressing channel of the wire pressing plate extends outwardly along the central axis of the wire pressing plate to the edge of the wire pressing plate.

3. The electronic stethoscope pickup cavity based on an electret microphone according to claim 2, characterized in that: There are two wires on the back of a microphone, and there is one wire pressing channel on the wire pressing plate, and one channel accommodates two wires.

4. The electronic stethoscope pickup cavity based on an electret microphone according to claim 2, characterized in that: There are two wires on the back of a microphone, and there are two wire pressing channels on the wire pressing plate, and one channel accommodates one wire.

5. The electronic stethoscope pickup cavity based on an electret microphone according to claim 3 or 4, characterized in that: The base of the stethoscope head is in the shape of a trumpet, the tail of which is sealed by a disc, a fixing hole and a wire through hole are left in the middle of the disc, and a card slot is provided at the head portion, which is connected with the stethoscope head cover by a buckle.

6. The electronic stethoscope pickup cavity based on an electret microphone according to claim 5, characterized in that: The depth of the inner depression is 1.6-2.0 mm.

7. The electronic stethoscope pickup cavity based on an electret microphone according to claim 6, characterized in that: The inwardly recessed depth of the diaphragm is 1.8 mm.

8. An electronic stethoscope based on an electret microphone, characterized in that: It comprises an electronic stethoscope pickup cavity based on an electret microphone and an electronic stethoscope grip according to any one of claims 2 to 7, wherein the electronic stethoscope grip comprises a shell, and the shell interior comprises a display module for displaying auscultation data, a processing module for processing and converting auscultation data, a power supply module for supplying energy, and an operation module for providing electronic stethoscope operation.

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