An ear muff device

Abstract

The application relates to the ear cover technical field and discloses an ear cover device. The resonance frequency of an acoustic vibration system formed by a first cavity and a sound transmission channel of the ear cover device is in a preset frequency band, and the quality factor of the acoustic vibration system is greater than a preset value, so that the vibration direction of sound waves transmitted from the first cavity to a second cavity is opposite to the vibration direction of original sound waves in the second cavity. In this way, the sound waves transmitted from the first cavity to the second cavity interfere with the original sound waves in the second cavity to weaken the original sound waves in the second cavity, so that the noise in the second cavity is reduced, that is, the noise transmitted to the user's ear is reduced, and therefore the passive noise reduction effect of the ear cover device is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of earmuffs, in particular to an earmuff device. BACKGROUND

[0002] Users usually wear earmuffs to isolate noise in a noisy environment. The current earmuffs usually isolate noise by physical means. For example, the earmuffs can be made of sponge or other sound-absorbing materials to achieve passive noise reduction effect.

[0003] However, due to the fact that noise in the environment can be transmitted through the ear cover and also enter the user's ear through the gap between the ear cover and the skin, and considering the wearing comfort of the earmuffs, the ear cover cannot be too hard and the sponge density cannot be too large, all the above factors result in poor passive noise reduction effect of the current earmuffs, especially for low-frequency noise. SUMMARY

[0004] Therefore, the present application mainly solves the technical problem of providing an earmuff device capable of improving the passive noise reduction effect of the earmuff device.

[0005] To solve the above technical problem, one technical solution adopted by the present application is to provide an earmuff device. The earmuff device comprises an ear shell assembly, the ear shell assembly is internally provided with a first cavity and a sound transmission channel, and the first cavity is communicated to the outside through the sound transmission channel. The earmuff device further comprises an ear cover, the ear cover is arranged outside the ear shell assembly, and the ear cover cooperates with the ear shell assembly to form a second cavity, wherein the second cavity is communicated with the first cavity, and the user's ear is located in the second cavity when the user wears the earmuff device. The resonance frequency of the acoustic vibration system constituted by the first cavity and the sound transmission channel is in a preset frequency band, and the quality factor of the acoustic vibration system is greater than a preset value, so that the vibration direction of the sound wave transmitted from the first cavity to the second cavity is opposite to the vibration direction of the original sound wave in the second cavity.

[0006] In an embodiment of the present application, the phase of the sound wave transmitted from the first cavity to the second cavity is opposite to the phase of the original sound wave in the second cavity.

[0007] In an embodiment of the present application, the preset value is 5.

[0008] In an embodiment of the present application, the ear shell assembly comprises a damping member, the first cavity is communicated with the second cavity through the damping member; the quality factor is a fusion of a damping factor, a first acoustic capacity factor and a first acoustic mass factor, the damping factor is a product of a damping value and a damping coefficient of the damping member, the first acoustic capacity factor is a product of a volume of the first cavity and a first acoustic capacity coefficient, and the first acoustic mass factor is a product of a sound transmission channel parameter and a first acoustic mass coefficient, the sound transmission channel parameter is a ratio of a sound transmission channel length to the square of a sound transmission channel diameter.

[0009] In an embodiment of the present application, the ear shell assembly comprises a damping member, the first cavity is communicated with the second cavity through the damping member; the volume of the first cavity is V, the length of the sound transmission channel is L, the diameter of the sound transmission channel is D, the damping of the damping member is R, and the quality factor is Q;

[0010] wherein,

[0011] In an embodiment of the present application, the frequency of each frequency point in the preset frequency band is less than 300 Hz.

[0012] In an embodiment of the present application, the resonance frequency is the fusion of the second acoustic capacity factor and the second acoustic mass factor, the second acoustic capacity factor is the product of the volume of the first cavity and the second acoustic capacity coefficient, the second acoustic mass factor is the product of the sound transmission channel parameter and the second acoustic mass coefficient, and the sound transmission channel parameter is the ratio of the length of the sound transmission channel to the square of the diameter of the sound transmission channel.

[0013] In an embodiment of the present application, the volume of the first cavity is V, the length of the sound transmission channel is L, the diameter of the sound transmission channel is D, and the resonance frequency is F0.

[0014] wherein,

[0015] In an embodiment of the present application, the volume of the first cavity is 50 mL to 80 mL; the length of the sound transmission channel is 10 mm to 25 mm; and the diameter of the sound transmission channel is 1 mm to 3 mm.

[0016] In an embodiment of the present application, the ear shell assembly comprises an ear shell, a damping member and a sound transmission tube; the ear shell and the damping member cooperatively form a first cavity, and the damping member and the ear shell cooperatively form a second cavity, the first cavity is communicated with the second cavity through the damping member; the sound transmission tube is arranged in the ear shell, and the sound transmission tube is provided with a sound transmission channel.

[0017] In an embodiment of the present application, the normal projection of the damping member on the reference plane covers the normal projection of the second cavity on the reference plane; wherein the reference plane is perpendicular to the relative direction of the first cavity and the second cavity.

[0018] In an embodiment of the present application, the sound transmission tube is away from the second cavity relative to the damping member.

[0019] The beneficial effects of the present application are: different from the prior art, the present application provides an earmuff device. The resonance frequency of the acoustic vibration system composed of the first cavity and the sound transmission channel of the earmuff device is in the preset frequency band, and the quality factor of the acoustic vibration system is greater than the preset value, so that the vibration direction of the sound wave transmitted from the first cavity to the second cavity is opposite to the vibration direction of the original sound wave in the second cavity. In this way, the sound wave transmitted from the first cavity to the second cavity will interfere with the original sound wave in the second cavity and weaken the original sound wave in the second cavity, so that the noise in the second cavity is reduced, that is, the noise transmitted to the user's ear is reduced, thus helping to improve the passive noise reduction effect of the earmuff device. BRIEF DESCRIPTION OF DRAWINGS

[0020] The drawings incorporated into the specification and forming part of the specification, show embodiments consistent with the present application, and together with the specification, serve to explain the principles of the present application. In addition, these drawings and the written description are not intended to limit the scope of the inventive concept in any way, but to illustrate the inventive concept for those skilled in the art by reference to specific embodiments.

[0021] Figure 1 is a schematic diagram of the noise reduction depth of the prior art earmuff at each frequency point;

[0022] Figure 2 is a schematic diagram of the structure of an embodiment of the earmuff device of the present application using a head-mounted design;

[0023] Figure 3 is a schematic diagram of the structure of an embodiment of the earmuff device of the present application;

[0024] Figure 4 is a schematic diagram of the phase of the sound wave transmitted from the first cavity to the second cavity of the present application at each frequency point;

[0025] Figure 5 is a schematic diagram of the passive noise reduction effect of the earmuff device of the present application compared with the passive noise reduction effect of the prior art earmuff. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme of the embodiments of the present application will be described below in a clear and complete manner. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application. In the case of no conflict, the embodiments described below and the features in the embodiments can be combined with each other.

[0027] To address the technical problem of poor passive noise cancellation in existing earmuffs, one embodiment of this application provides an earmuff device. The earmuff device includes an ear shell assembly, which internally comprises a first cavity and a sound-transmitting channel, wherein the first cavity is connected to the outside via the sound-transmitting channel. The earmuff device also includes an ear sleeve, which is disposed outside the ear shell assembly and, together with the ear shell assembly, forms a second cavity, wherein the second cavity is connected to the first cavity, and when the user wears the earmuff device, the user's ear is located within the second cavity. The resonant frequency of the acoustic vibration system formed by the first cavity and the sound-transmitting channel is within a preset frequency band, and the quality factor of the acoustic vibration system is greater than a preset value, causing the vibration direction of the sound wave transmitted from the first cavity to the second cavity to be opposite to the vibration direction of the original sound wave in the second cavity. This will be described in detail below.

[0028] Please see Figure 1 , Figure 1 This is a schematic diagram of the noise reduction depth of existing earmuffs at various frequency points.

[0029] Figure 1 This demonstrates the noise reduction depth of existing earmuffs at various frequency points. Noise reduction depth should be understood as the noise reduction effect of the earmuffs at each frequency point. Generally, the greater the noise reduction depth, the better the noise reduction effect, and vice versa. Of course, Figure 1 This demonstrates the passive noise reduction effect achieved by the earmuffs through physical means.

[0030] It can be seen that the noise reduction depth of existing earmuffs in the low frequency band (around 200Hz and below) is close to 0dB, which means that the passive noise reduction effect of existing earmuffs in the low frequency band is poor, making existing earmuffs unsuitable for environments with a lot of low frequency noise, such as airplanes and subways.

[0031] Please see Figure 2 and Figure 3 , Figure 2 This is a schematic diagram of an embodiment of the earmuff device of this application, which adopts a headband design. Figure 3 This is a schematic diagram of the structure of an embodiment of the earmuff device of this application.

[0032] In one embodiment, the earmuff device 10 can be a headband design, i.e., two earmuff devices 10 are connected by a headband bracket 20, which is worn on the user's head, and the two earmuff devices 10 respectively cover the user's left and right ears, such as... Figure 2 As shown. Of course, in other embodiments of this application, the earmuff device 10 can be designed independently, and the user can directly wear the earmuff device 10 on the ear without the headband 20, which is not limited here.

[0033] Specifically, the earmuff device 10 includes an ear shell assembly 11. The ear shell assembly 11 serves as the basic carrier of the earmuff device 10, supporting and protecting other components of the earmuff device 10. The ear shell assembly 11 internally comprises a first cavity 12 and a sound-transmitting channel 13. The first cavity 12 is connected to the outside through the sound-transmitting channel 13. Sound waves from outside the earmuff device 10 enter the first cavity 12 through the sound-transmitting channel 13.

[0034] The earmuff device 10 also includes an ear sleeve 14. The ear sleeve 14 is disposed outside the ear shell assembly 11, and the ear sleeve 14 and the ear shell assembly 11 cooperate to form a second cavity 15. When the user wears the earmuff device 10, the user's ear is located in the second cavity 15. The second cavity 15 is also connected to the first cavity 12, and sound waves entering the first cavity 12 from the sound transmission channel 13 will pass through the first cavity 12 to reach the second cavity 15. Sound waves outside the earmuff device 10 will also be transmitted through the ear sleeve 14 and enter the second cavity 15 through the slit between the ear sleeve 14 and the skin; this part of the sound waves is the original sound waves in the second cavity 15.

[0035] The first cavity 12 and the sound-transmitting channel 13 constitute an acoustic vibration system. The first cavity 12 mainly provides acoustic capacitance for the acoustic vibration system, while the sound-transmitting channel 13 mainly provides acoustic quality. The resonant frequency of the acoustic vibration system is within a preset frequency band, and the quality factor of the acoustic vibration system is greater than a preset value. As a result, the vibration direction of the sound wave transmitted from the first cavity 12 to the second cavity 15 is opposite to the vibration direction of the original sound wave in the second cavity 15. The sound wave transmitted from the first cavity 12 to the second cavity 15 interferes with the original sound wave in the second cavity 15, weakening the original sound wave in the second cavity 15. This reduces the noise in the second cavity 15, i.e., reduces the noise transmitted to the user's ear, thus improving the passive noise reduction effect of the earmuff device 10.

[0036] Furthermore, since the phase of the external sound wave before entering the first cavity 12 through the sound-permeable channel 13 is not significantly different from the phase of the original sound wave in the second cavity 15, this embodiment, through the aforementioned acoustic vibration system, ensures that the phase of the sound wave transmitted from the first cavity 12 to the second cavity 15 is nearly opposite to the phase of the original sound wave in the second cavity 15. Ideally, the phase of the sound wave transmitted from the first cavity 12 to the second cavity 15 should be opposite to the phase of the original sound wave in the second cavity 15. When the sound wave transmitted from the first cavity 12 to the second cavity 15 interferes with the original sound wave in the second cavity 15, the sound wave transmitted from the first cavity 12 to the second cavity 15 can cancel out the original sound wave in the second cavity 15 as much as possible, minimizing the noise in the second cavity 15, thus maximizing the passive noise reduction effect of the earmuff device 10.

[0037] The following description is based on the design concept that the phase of the sound wave transmitted from the first cavity 12 to the second cavity 15 is approximately opposite to the phase of the original sound wave in the second cavity 15. Of course, in other embodiments of this application, the vibration direction of the sound wave transmitted from the first cavity 12 to the second cavity 15 may be opposite to the vibration direction of the original sound wave in the second cavity 15, and this is not limited here.

[0038] In one embodiment, the quality factor of the acoustic vibration system is greater than a preset value, wherein the preset value is 5. In this way, it can be ensured that the phase of the sound wave entering the first cavity 12 from the sound transmission channel 13 undergoes a large change after passing through the first cavity 12, so that the vibration direction of the sound wave transmitted from the first cavity 12 to the second cavity 15 is opposite to the vibration direction of the original sound wave in the second cavity 15.

[0039] It is understandable that the larger the quality factor, the closer the phase change of the sound wave will be to 180° after passing through the first cavity 12.

[0040] Specifically, the ear shell assembly 11 includes a damping element 112, through which the first cavity 12 is connected to the second cavity 15. Sound waves in the first cavity 12 reach the second cavity 15 through the damping element 112. The damping element 112 provides damping for the acoustic vibration system.

[0041] The cross-section of the sound-transmitting channel 13 can be circular. The cross-section of the sound-transmitting channel 13 should be understood as a section perpendicular to its length direction (i.e., the extension direction). Of course, in other embodiments of this application, the cross-section of the sound-transmitting channel 13 can also be square, elliptical, irregular polygonal, etc., and is not limited here. The following description uses a circular cross-section of the sound-transmitting channel 13 as an example, only for illustrative purposes and not as a limitation.

[0042] In one embodiment, the quality factor is a fusion of the damping factor, the first acoustic capacitance factor, and the first acoustic quality factor. The damping factor is the damping value and damping coefficient of the damping element. The first acoustic capacitance factor is the product of the first cavity volume and the first acoustic capacitance coefficient. The first acoustic quality factor is the product of the sound transmission channel parameter and the first acoustic quality coefficient. The sound transmission channel parameter is the ratio of the sound transmission channel length to the square of the sound transmission channel diameter. The damping coefficient, the first acoustic capacitance coefficient, and the first acoustic quality coefficient can be set as needed.

[0043] Specifically, the volume of the first cavity 12 is V, the length of the sound-transmitting channel 13 is L, the diameter of the sound-transmitting channel 13 is D, the damping provided by the damping element 112 is R, the quality factor is Q, and the acoustic mass of the acoustic vibration system is M. a The sound and volume are C a .in,

[0044]

[0045] It can be seen that the quality factor of the acoustic vibration system is related to the volume of the first cavity 12, the length and diameter of the sound transmission channel 13, and the damping of the damping element 112. Therefore, by reasonably setting the volume of the first cavity 12, the length and diameter of the sound transmission channel 13, and the damping of the damping element 112, this embodiment can make the quality factor of the acoustic vibration system greater than a preset value, thereby causing a significant change in the phase of the sound wave entering the first cavity 12 from the sound transmission channel 13 after passing through the first cavity 12.

[0046] In one embodiment, considering that the passive noise reduction effect of the earmuffs in the prior art is poor in the low frequency band, the resonant frequency of the acoustic vibration system in this embodiment is in a preset frequency band, wherein the frequency of each frequency point in the preset frequency band is less than 300Hz, that is, the preset frequency band is a low frequency band.

[0047] By means of the above method, the vibration direction of the low-frequency sound wave transmitted from the first cavity 12 to the second cavity 15 is opposite to the vibration direction of the original low-frequency sound wave in the second cavity 15, thereby weakening the original low-frequency sound wave in the second cavity 15 and reducing the low-frequency noise in the second cavity 15. That is, the low-frequency noise transmitted to the user's ear is reduced, which is beneficial to improving the passive noise reduction effect of the earmuff device 10 in the low-frequency band. In other words, the earmuff device 10 of this embodiment can be used in environments with a lot of low-frequency noise, such as airplanes and subways.

[0048] Of course, in other embodiments of this application, the preset frequency band can be other frequency bands besides the low frequency band, such as mid frequency, high frequency, etc., that is, the embodiments of this application can be applied to improve the passive noise reduction effect of the earmuff device 10 in other frequency bands.

[0049] The resonant frequency is the fusion of the second acoustic capacity factor and the second acoustic quality factor. The second acoustic capacity factor is the product of the first cavity volume and the second acoustic capacity coefficient. The second acoustic quality factor is the product of the sound transmission channel parameter and the second acoustic quality coefficient. The sound transmission channel parameter is the ratio of the sound transmission channel length to the square of the sound transmission channel diameter. The second acoustic capacity coefficient and the second acoustic quality coefficient can be set as needed.

[0050] Specifically, the volume of the first cavity 12 is V, the length of the sound-transmitting channel 13 is L, the diameter of the sound-transmitting channel 13 is D, the resonant frequency is F0, and the acoustic mass of the acoustic vibration system is M. a The sound and volume are C a .in,

[0051]

[0052] It can be seen that the resonant frequency of the acoustic vibration system is related to the volume of the first cavity 12, the length of the sound-transmitting channel 13, and the diameter of the sound-transmitting channel 13. Since the noise reduction depth reaches its maximum at the resonant frequency position, this embodiment can adjust the resonant frequency position when the noise reduction depth reaches its maximum by reasonably setting the volume of the first cavity 12, the length of the sound-transmitting channel 13, and the diameter of the sound-transmitting channel 13.

[0053] In one embodiment, considering the factors determining the resonant frequency and quality factor of the acoustic vibration system as described in the above embodiments, this embodiment preferably sets the volume of the first cavity 12 to 50mL to 80mL, the length of the sound transmission channel 13 to 10mm to 25mm, and the diameter of the sound transmission channel 13 to 1mm to 3mm.

[0054] In this way, the phase of the low-frequency sound wave transmitted from the first cavity 12 to the second cavity 15 can be ensured to be nearly opposite to the phase of the original low-frequency sound wave in the second cavity 15, thereby maximally weakening the original low-frequency sound wave in the second cavity 15, so that the low-frequency noise in the second cavity 15 is reduced to the maximum extent, that is, the low-frequency noise transmitted to the user's ear is reduced to the maximum extent, and the passive noise reduction effect of the earmuff device 10 in the low-frequency band is maximized.

[0055] In an exemplary embodiment, the volume of the first cavity 12 is set to 80 mL, the length of the sound transmission channel 13 is set to 20 mm, the diameter of the sound transmission channel 13 is set to 1 mm, and the damping of the damping element 112 is reasonably set so that the deepest noise reduction depth of the earmuff device 10 in this embodiment reaches -29 dB near 200 Hz, which can meet the needs of most environments with a lot of low-frequency noise.

[0056] In another exemplary embodiment, the volume of the first cavity 12 is set to 50mL, the length of the sound transmission channel 13 is set to 25mm, the diameter of the sound transmission channel 13 is set to 1mm, and the damping of the damping element 112 is reasonably set. This also allows the earmuff device 10 of this embodiment to achieve a maximum noise reduction depth of -29dB near 200Hz, which can meet the needs of most environments with a lot of low-frequency noise.

[0057] Optionally, the damping element 112 can be a mesh fabric with vents, etc. The damping provided by the damping element 112 can be set by selecting the amount of air permeability of the damping element 112, which is not limited here.

[0058] This embodiment employs a first-order low-pass filter to fit the passive noise reduction effect of the earmuff. Specifically, the resonant frequency of the acoustic vibration system is set to be in the low-frequency band, and the quality factor is relatively large, causing a significant change in the phase of the sound wave entering the first cavity 12 from the sound-transmitting channel 13 after passing through the first cavity 12. Figure 4The phase of the sound wave transmitted from the first cavity 12 to the second cavity 15 at various frequencies is shown. It can be clearly seen that the sound wave transmitted from the first cavity 12 to the second cavity 15 has a phase change of nearly 180° around 200Hz.

[0059] Figure 5 This paper demonstrates a comparison between the passive noise cancellation effect of the earmuff device 10 according to the present application embodiment and the passive noise cancellation effect of prior art earmuffs. Curve I shows the noise reduction depth of the earmuff device 10 at various frequency points, while curve II shows the noise reduction depth of prior art earmuffs at various frequency points. Clearly, the earmuff device 10 of the present application embodiment has a deeper noise reduction depth at various frequency points, i.e., a better noise reduction effect. Specifically, the deepest noise reduction depth of the earmuff device 10 near 200Hz reaches -29dB.

[0060] Please continue reading. Figure 3 In one embodiment, the ear shell assembly 11 includes an ear shell 111, a damping element 112, and a sound-permeable tube 113. The ear shell 111 and the damping element 112 cooperate to form a first cavity 12, and the damping element 112 and the ear sleeve 14 cooperate to form a second cavity 15. The first cavity 12 is connected to the second cavity 15 through the damping element 112. The sound-permeable tube 113 is disposed on the ear shell 111, and a sound-permeable channel 13 is provided in the sound-permeable tube 113.

[0061] The earcup device 10 of this embodiment differs from existing over-ear headphones in that it does not have a speaker. Users isolate noise by wearing the earcup device 10, which serves as a physical means of noise isolation, achieving a passive noise isolation effect.

[0062] Since the earcup device 10 of this embodiment does not have a speaker, the damping member 112 can be provided on the entire surface. Specifically, the damping member 112 is on the reference plane (e.g., Figure 3 The orthographic projection of the first cavity 12 onto the mid-plane α (hereinafter the same) covers the orthographic projection of the second cavity 15 onto the reference plane. The reference plane is perpendicular to the relative direction of the first cavity 12 and the second cavity 15 (e.g., ...). Figure 3 (As indicated by the middle arrow X).

[0063] Furthermore, in this embodiment, the sound-permeable tube 113 is positioned far from the damping element 112 relative to the second cavity 15. In this way, sound waves entering through the sound-permeable tube 113 will pass through the entire first cavity 12 before being transmitted to the second cavity 15, which improves the space utilization of the first cavity 12 and allows it to provide a larger acoustic capacity. If the sound-permeable tube 113 were close to the second cavity 15, the sound waves entering through the sound-permeable tube 113 would likely be transmitted directly to the second cavity 15 through the damping element 112, resulting in a less significant phase change in that portion of the sound waves and failing to achieve a noise reduction effect.

[0064] In summary, the earmuff device provided in this application has an acoustic vibration system whose resonant frequency, formed by the first cavity and the sound-transmitting channel, is within a preset frequency band, and whose quality factor is greater than a preset value. This causes the vibration direction of the sound wave transmitted from the first cavity to the second cavity to be opposite to the vibration direction of the original sound wave in the second cavity. As a result, the sound wave transmitted from the first cavity to the second cavity interferes with the original sound wave in the second cavity, weakening the original sound wave in the second cavity. This reduces the noise in the second cavity, i.e., reduces the noise transmitted to the user's ear. Therefore, it helps improve the passive noise reduction effect of the earmuff device, and the noise reduction effect of the earmuff device in this application is less affected by the tightness of the fit.

[0065] Furthermore, the earmuff device of this application has a simple structure, fewer structural components, and a lighter overall weight than earmuffs of the prior art.

[0066] Furthermore, in this application, unless otherwise expressly specified and limited, the terms "connected," "linked," "stacked," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two elements or the interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An earmuff device, characterized in that, include: The ear shell assembly has a first cavity and a sound-transmitting channel inside, wherein the first cavity is connected to the outside through the sound-transmitting channel; An ear cup is disposed outside the ear shell assembly, and the ear cup and the ear shell assembly cooperate to form a second cavity, wherein the second cavity communicates with the first cavity, and when the user wears the ear cup device, the user's ear is located in the second cavity; The ear shell assembly includes an ear shell, a damping element, and a sound-permeable tube; the ear shell and the damping element cooperate to form the first cavity, and the damping element and the ear sleeve cooperate to form the second cavity, the first cavity being connected to the second cavity through the damping element; the sound-permeable tube is disposed on the ear shell, and the sound-permeable tube has a sound-permeable channel. The resonant frequency of the acoustic vibration system formed by the first cavity and the sound-transmitting channel is in a preset frequency band, and the quality factor of the acoustic vibration system is greater than a preset value, so that the vibration direction of the sound wave transmitted from the first cavity to the second cavity is opposite to the vibration direction of the original sound wave in the second cavity. Wherein, the quality factor is a fusion of the damping factor, the first acoustic volume factor, and the first acoustic quality factor; the damping factor is the product of the damping value of the damping element and the damping coefficient; the first acoustic volume factor is the product of the first cavity volume and the first acoustic volume coefficient; the first acoustic quality factor is the product of the sound transmission channel parameter and the first acoustic quality coefficient; and the sound transmission channel parameter is the ratio of the sound transmission channel length to the square of the sound transmission channel diameter.

2. The earmuff device according to claim 1, characterized in that, The phase of the sound wave transmitted from the first cavity to the second cavity is opposite to the phase of the original sound wave in the second cavity.

3. The earmuff device according to claim 1, characterized in that, The preset value is 5.

4. The earmuff device according to claim 1, characterized in that, The frequency of each frequency point in the preset frequency band is less than 300Hz.

5. The earmuff device according to claim 4, characterized in that, The resonant frequency is the fusion of the second acoustic compatibility factor and the second acoustic quality factor. The second acoustic compatibility factor is the product of the first cavity volume and the second acoustic compatibility coefficient. The second acoustic quality factor is the product of the sound transmission channel parameter and the second acoustic quality coefficient. The sound transmission channel parameter is the ratio of the sound transmission channel length to the square of the sound transmission channel diameter.

6. The earmuff device according to claim 5, characterized in that, The volume of the first cavity is 50 mL to 80 mL; The length of the acoustic channel is 10mm to 25mm; The diameter of the acoustic channel is 1 mm to 3 mm.

7. The earmuff device according to claim 1, characterized in that, The orthographic projection of the damping element on the reference plane covers the orthographic projection of the second cavity on the reference plane; The reference plane is perpendicular to the relative directions of the first cavity and the second cavity.

8. The earmuff device according to claim 1, characterized in that, The sound-permeable tube is located away from the second cavity relative to the damping element.

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