Electroacoustic transducer and earphone

Abstract

The present disclosure provides an electroacoustic transducer and an earphone. The electroacoustic transducer is provided with a hollow channel passing through the electroacoustic transducer in the axial direction thereof; the electroacoustic transducer comprises a vibration system and a magnetic circuit system; the vibration system comprises a diaphragm, a first voice coil and a second voice coil; the diaphragm surrounds a hollow channel; the first voice coil is connected to the diaphragm and surrounds the hollow channel; the second voice coil is connected to the diaphragm and surrounds the periphery of the first voice coil; and the magnetic circuit system is used for driving the first voice coil and the second voice coil to move so that the diaphragm vibrates to produce sound. By providing the hollow channel in the electroacoustic transducer, the length of the airflow or sound propagation path within the earphone housing can be minimized, effectively improving the acoustic transparency of the earphone. Moreover, by providing the first voice coil and the second voice coil, when the electroacoustic transducer operates, the two voice coils operate simultaneously to provide a greater driving force to the diaphragm, effectively enhancing product performance and improving high-frequency effects.

Description

An electroacoustic transducer and headphones

[0001] This disclosure claims priority to Chinese Patent Application No. 202421430921.7, filed on June 20, 2024, entitled “An Electroacoustic Transducer and Headphones”, the entire contents of which are incorporated herein by reference.

[0002] This disclosure claims priority to Chinese Patent Publication No. 202421430143.1, filed on June 20, 2024, entitled “A Headphone”, the entire contents of which are incorporated herein by reference.

[0003] This disclosure claims priority to Chinese Patent Application No. 202421430910.9, filed on June 20, 2024, entitled "An Earphone", the entire contents of which are incorporated herein by reference.

[0004] This disclosure claims priority to Chinese Patent Publication No. 202410808541.0, filed on June 20, 2024, entitled "An Earphone", the entire contents of which are incorporated herein by reference. Technical Field

[0005] This disclosure relates to the field of wearable device technology, and more particularly to an electroacoustic transducer and headphones. Background Technology

[0006] Electroacoustic transducers, such as loudspeakers or horns, are devices that convert audio signals into sound for playback. Therefore, electroacoustic transducers are widely used in headphones.

[0007] In related technologies, in order to improve the comfort and clarity of headphones, smaller speakers are used. However, in these technologies, the sound output of smaller speakers is not ideal, and the improvement in the clarity of headphones is limited, thus failing to effectively enhance the user's listening experience. Summary of the Invention

[0008] In view of the above problems, this disclosure provides an electroacoustic transducer and headphones, which can effectively improve the user's listening experience.

[0009] To achieve the above objectives, the present disclosure provides the following technical solutions:

[0010] A first aspect of this disclosure provides an electroacoustic transducer having a hollow channel extending along its own axial direction. The electroacoustic transducer includes a vibration system and a magnetic circuit system. The vibration system includes a diaphragm, a first voice coil, and a second voice coil. The diaphragm surrounds the hollow channel. The first voice coil is connected to the diaphragm and surrounds the hollow channel. The second voice coil is connected to the diaphragm and surrounds the outer periphery of the first voice coil.

[0011] The magnetic circuit system has a magnetic gap, in which at least a portion of the first voice coil and at least a portion of the second voice coil are located; the magnetic circuit system is used to drive the first voice coil and the second voice coil to move so that the diaphragm vibrates to produce sound.

[0012] A second aspect of this disclosure provides an earphone, the earphone including a housing and the electroacoustic transducer described in the first aspect, the electroacoustic transducer being disposed in the housing.

[0013] A third aspect of this disclosure provides an earphone, including a housing, an electroacoustic transducer, and an opening / closing assembly. The electroacoustic transducer is disposed within the housing and has a hollow channel extending along its own axial direction. The housing has a first sound outlet located on the side of the housing facing the ear, and the hollow channel communicates with the first sound outlet. The housing also includes an outer side wall disposed opposite to the electroacoustic transducer, and the outer side wall has an end facet that connects the hollow channel to the external environment.

[0014] The opening and closing component is used to open or close the connection between the first sound outlet and the external environment.

[0015] A fourth aspect of this disclosure provides an earphone, including a housing and an electroacoustic transducer, wherein the electroacoustic transducer is disposed within the housing and has a hollow channel extending along its own axial direction.

[0016] The housing has a first sound outlet and an end face. The first sound outlet is located on the side of the housing facing the ear and is connected to the hollow channel. The end face is located on the side of the housing away from the ear and is connected to the external environment and the hollow channel, respectively.

[0017] The earphone has a first resonant cavity formed on the side facing the ear. The first resonant cavity is connected to the first sound outlet. When the earphone is worn, the first resonant cavity covers the ear. The first resonant cavity is connected to the end face through the hollow channel, so that the first resonant cavity, the hollow channel and the end face form a first Helmholtz resonance system.

[0018] A second resonant cavity is also formed inside the housing. A second sound outlet is provided on the side of the housing away from the ear. The second resonant cavity is connected to the rear tuning hole of the electroacoustic transducer and the second sound outlet. The second resonant cavity and the second sound outlet form a second Helmholtz resonance system.

[0019] The end face and the second sound outlet hole constitute a dipole sound source within a preset frequency range.

[0020] In the electroacoustic transducer and headphones provided in this disclosure, a hollow channel is provided in the electroacoustic transducer. Thus, when the electroacoustic transducer is installed in the headphone shell, it can cooperate with the headphone shell to provide an open listening environment for the ears, allowing users to listen to music while also hearing external sounds, satisfying different listening needs. It also dissipates heat inside the headphones, keeping the ears comfortable. Furthermore, by using a hollow channel in the electroacoustic transducer, the path length of airflow or sound within the headphone shell is minimized, effectively improving the headphones' transparency. Moreover, by using a first voice coil and a second voice coil, both voice coils work simultaneously during operation, providing a greater driving force to the diaphragm, effectively improving product performance and enhancing high-frequency response.

[0021] In addition to the technical problems solved by the embodiments of this disclosure, the technical features constituting the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions described above, other technical problems that can be solved by the electroacoustic transducer and headphones provided by the embodiments of this disclosure, other technical features included in the technical solutions, and the beneficial effects brought about by these technical features will be further described in detail in the specific implementation. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 is a schematic diagram of the structure of the electroacoustic transducer provided in an embodiment of this disclosure;

[0024] Figure 2 is a cross-sectional view of the electroacoustic transducer shown in Figure 1;

[0025] Figure 3 is a cross-sectional view of the headphones provided in an embodiment of this disclosure;

[0026] Figure 4 is a schematic diagram of the first structure of the electroacoustic transducer provided in this embodiment of the present disclosure when the opening and closing component is installed;

[0027] Figure 5 is a schematic diagram of the second structure of the electroacoustic transducer provided in the embodiment of this disclosure when the opening and closing component is installed;

[0028] Figure 6 is a perspective view of the earphones provided in the embodiment of this disclosure in a sealed state;

[0029] Figure 7 is a perspective view of the headphones provided in the embodiment of this disclosure in the open state;

[0030] Figure 8 is a schematic diagram of the structure of the diaphragm, the first voice coil and the second voice coil provided in an embodiment of this disclosure;

[0031] Figure 9 is a first explosion diagram of the electroacoustic transducer provided in the embodiment of this disclosure;

[0032] Figure 10 is a cross-sectional view of an electroacoustic transducer provided in another embodiment of the present disclosure;

[0033] Figure 11 is a second explosion diagram of the electroacoustic transducer provided in an embodiment of this disclosure;

[0034] Figure 12 is a schematic diagram of the ear structure;

[0035] Figure 13 is a structural schematic diagram of the headphones when worn on the ear in the related technology from a first-view perspective;

[0036] Figure 14 is a structural schematic diagram of the headphones when worn on the ear in the related technology from a second perspective;

[0037] Figure 15 is a first cross-sectional view of the earphones provided in this embodiment of the present disclosure when worn in the ear;

[0038] Figure 16 is a second cross-sectional view of the earphones provided in this embodiment of the present disclosure when worn in the ear;

[0039] Figure 17 is a schematic diagram of the projection of the hollow channel, ear hole and end face hole provided in the embodiment of this disclosure onto the second reference plane H along the coronal axis direction;

[0040] Figure 18 is a perspective view of the headphones provided in the embodiment of this disclosure in the open state;

[0041] Figure 19 is a perspective view of the earphones provided in the embodiment of this disclosure in a sealed state;

[0042] Figure 20 is a third cross-sectional view of the earphones provided in this embodiment of the present disclosure when worn in the ear;

[0043] Figure 21 is a fourth cross-sectional view of the earphones provided in this embodiment of the present disclosure when worn in the ear;

[0044] Figure 22 is a fifth cross-sectional view of the earphones provided in this embodiment of the present disclosure when worn in the ear;

[0045] Figure 23 is a sixth cross-sectional view of the earphones provided in this embodiment of the present disclosure when worn in the ear;

[0046] Figure 24 is a perspective view of the headphones in the open state according to an embodiment of the present disclosure;

[0047] Figure 25 is a cross-sectional view of the headphones provided in an embodiment of this disclosure;

[0048] Figure 26 shows the frequency response curves of the sound emitted by the unadjusted front face and the second sound hole provided in this embodiment.

[0049] Figure 27 shows the frequency response curves of the sound emitted by the rear face of the adjustment parameters provided in this embodiment and the frequency response curve of the sound emitted by the second sound hole.

[0050] Figure 28 is a second cross-sectional view of the headphones provided in an embodiment of this disclosure;

[0051] Figure 29 is a cross-sectional view three of the headphones provided in the embodiment of this disclosure;

[0052] Figure 30 is a cross-sectional view four of the headphones provided in the embodiment of this disclosure;

[0053] Figure 31 is a perspective view of the headphones in a closed state according to an embodiment of the present disclosure;

[0054] Figure 32 is a cross-sectional view of the headphones provided in an embodiment of this disclosure;

[0055] Figure 33 is a schematic diagram of the plastic bracket provided in an embodiment of this disclosure. Detailed Implementation

[0056] Example 1

[0057] The present disclosure will now be described in detail with reference to embodiments.

[0058] Understandably, the electroacoustic transducer disclosed herein can be applied to electronic devices, such as headphones or wearable devices, which provide audio input by being close to or through the ear canal. When the electronic device is a headphone, the headphone can be a wired headphone, a true wireless stereo (TWS) headphone, or an open wearable stereo (OWS) headphone. For example, this disclosure describes the application of the electroacoustic transducer to over-ear headphones, where, when worn, the over-ear headphones cover the ear, enclosing the entire ear within the cavity formed by the headphones and the head.

[0059] It should be noted that in related technologies, in order to improve the comfort and transparency of headphones, headphones usually use relatively small speakers. However, in related technologies, the sound effect of small speakers is not ideal, and the improvement on the transparency of headphones is also limited, which cannot effectively improve the user's listening experience.

[0060] Based on this, please refer to Figures 1 and 2. Figure 1 is a structural schematic diagram of the electroacoustic transducer provided in this embodiment, and Figure 2 is a cross-sectional view of the electroacoustic transducer shown in Figure 1. This embodiment provides an electroacoustic transducer 20, which has a hollow channel 21 extending along its own axial direction. The electroacoustic transducer 20 includes a vibration system 22 and a magnetic circuit system 23. The vibration system 22 includes a diaphragm 221, a first voice coil 222, and a second voice coil 223. The diaphragm 221 surrounds the hollow channel 21. The first voice coil 222 is connected to the diaphragm 221 and surrounds the hollow channel 21. The second voice coil 223 is connected to the diaphragm 221 and surrounds the outer periphery of the first voice coil 222.

[0061] The magnetic circuit system 23 has a magnetic gap, in which at least a portion of the first voice coil 222 and at least a portion of the second voice coil 223 are located; the magnetic circuit system 23 is used to drive the first voice coil 222 and the second voice coil 223 to move so that the diaphragm 221 vibrates to produce sound.

[0062] Understandably, since the electroacoustic transducer 20 is equipped with a through hollow channel 21, the electroacoustic transducer 20 is roughly in the shape of a ring.

[0063] It is also understood that, referring to Figure 3, which is a cross-sectional view of the headphones provided in this embodiment of the present disclosure, the electroacoustic transducer 20 of the present disclosure can be disposed in the housing 10 of the headphones 100. The housing 10 of the headphones 100 has an end face 121 communicating with the external environment, and the housing 10 of the headphones 100 has a first sound outlet 11 located on the side of the housing 10 facing the ear 200. When the electroacoustic transducer 20 is installed in the housing 10, the hollow channel 21 of the electroacoustic transducer 20 communicates with the first sound outlet 11 and the end face 121. It is understood that when the headphones 100 are worn on the ear 200, the sound signal emitted by the electroacoustic transducer 20 can be transmitted through the first sound outlet 11 to the ear canal and then enter the ear canal.

[0064] For example, the housing 10 includes an outer wall 12, which is disposed opposite to the electroacoustic transducer 20 in the axial direction of the transducer 20. The outer wall 12 is provided with an end face 121, which connects the hollow channel 21 to the external environment. Thus, since the first sound outlet 11 is connected to the hollow channel 21, the first sound outlet 11 can be connected to the external environment through the hollow channel 21 and the end face 121, thereby enabling airflow and sound transmission.

[0065] It is understood that the electroacoustic transducer 20 provided in this embodiment of the present disclosure has a hollow channel 21 that communicates with the first sound outlet 11. When the electroacoustic transducer 20 is installed in the housing 10 of the earphone 100, the hollow channel 21 of the electroacoustic transducer 20 communicates with the end face 121 on the housing 10 of the earphone 100. In this way, the first sound outlet 11 communicates with the end face 121 through the hollow channel 21, thereby realizing the communication between the first sound outlet 11 and the external environment. This provides an open listening environment for the ear 200, allowing the user to listen to music while also listening to external sounds, meeting the user's different listening needs. It can also dissipate the heat inside the earphone 100, keeping the ear 200 in a comfortable state.

[0066] Furthermore, by adopting the method of setting a hollow channel 21 in the electroacoustic transducer 20, the path length of airflow or sound flowing between the first sound outlet 11 and the end face 121 can be minimized, effectively improving the transparency of the headphones 100. Moreover, by setting the end face 121 on the outer wall 12 opposite to the electroacoustic transducer 20, the distance between the end face 121 and the hollow channel 21 can be further reduced, further reducing the path length of airflow or sound flowing between the first sound outlet 11 and the end face 121, thereby further improving the transparency of the headphones 100.

[0067] In addition, by setting the first voice coil 222 and the second voice coil 223, the two voice coils work simultaneously when the electroacoustic transducer 20 is working, providing the diaphragm 221 with a greater driving force, which can effectively improve product performance and improve high-frequency effect.

[0068] To enable the opening or closing of the hollow channel 21, please refer to Figures 4 and 5. Figure 4 is a first structural schematic diagram of the electroacoustic transducer provided in this embodiment with the opening / closing component installed, and Figure 5 is a second structural schematic diagram of the electroacoustic transducer provided in this embodiment with the opening / closing component installed. It is understood that the opening / closing component in Figure 4 is in the open state, and the opening / closing component in Figure 5 is in the closed state. The electroacoustic transducer 20 may further include an opening / closing component 30, which is disposed in the hollow channel 21 and used to open or close the hollow channel 21.

[0069] Understandably, when the opening / closing component 30 is in the closed state, the hollow channel 21 is closed, and the first sound outlet 11 and the end face 121 are not connected, thus providing a sealed listening environment for the ear 200 and meeting the user's need for an immersive experience. When the opening / closing component 30 is in the open state, the hollow channel 21 is open, and the first sound outlet 11 can connect with the end face 121 through the hollow channel 21, thereby enabling the first sound outlet 11 to connect with the external environment, thus providing an open listening environment for the ear 200, allowing the user to listen to music while also hearing external sounds, meeting different listening needs of the user, and also dissipating heat inside the earphone 100, keeping the ear 200 in a comfortable state.

[0070] It can also be understood that the shapes of the first sound hole 11 and the end face 121 can be circular, but are not limited to circular. They can also include one or more of the following shapes: elliptical, racetrack-shaped, triangular, rectangular, polygonal, or other complex shapes with decorative features. This disclosure does not impose any restrictions on these shapes.

[0071] In order to improve the transparency of the headphone 100, the size of the first sound outlet 11, the end face 121 and the hollow channel 21 can be made as large as possible. That is, the larger the cross-sectional area of ​​the first sound outlet 11, the end face 121 and the hollow channel 21, the better the transparency of the headphone 100.

[0072] For example, the minimum cross-sectional area of ​​the first sound outlet 11 is greater than or equal to 15 square millimeters. This effectively improves the transparency of the earphone 100 and also improves the quality of sound transmission. More preferably, the minimum cross-sectional area of ​​the first sound outlet 11 is greater than or equal to 25 square millimeters, and even more preferably, the minimum cross-sectional area of ​​the first sound outlet 11 is greater than or equal to 40 square millimeters.

[0073] It should be noted that the opening / closing component 30, as a component for opening or closing the hollow channel 21, is mainly used for opening or closing the hollow channel 21. This disclosure does not impose specific limitations on its structure, as long as it can achieve the opening or closing of the hollow channel 21. For example, the opening / closing component 30 can be a shutter assembly similar to a "shutter," which may include multiple blades. These blades can move radially relative to the hollow channel 21, and can move closer together to achieve a closing function, or move further apart to achieve an opening function. For example, a perspective view of the headphone 100 in its sealed state is shown in Figure 6, and a perspective view of the headphone 100 in its open state is shown in Figure 7.

[0074] In some embodiments, when the electroacoustic transducer 20 is installed on the housing 10 of the earphone 100, the opening and closing component 30 of the electroacoustic transducer 20 can be connected to a linkage mechanism (not shown) provided on the housing 10. One end of the linkage mechanism is located outside the housing 10, and the other end of the linkage mechanism is connected to the opening and closing component 30, such as to the blade of the opening and closing component 30. The user drives the linkage mechanism to open or close the opening and closing component 30, thereby switching the earphone 100 between the open and sealed states.

[0075] In other embodiments, the linkage mechanism can be connected to a motor, which drives the linkage mechanism to open or close the opening and closing component 30. For example, the motor can receive instructions from the main control chip of the earphone 100 to control the opening and closing of the opening and closing component 30.

[0076] In some other embodiments, the opening and closing component 30 may be disposed opposite to the communication area of ​​the first sound outlet 11, the hollow channel 21 and the end face 121, for opening or closing the communication between the first sound outlet 11 and the external environment.

[0077] As specified above, the opening / closing component 30 is disposed at the hollow channel 21 of the electroacoustic transducer 20, and is used to open or close the hollow channel 21. It is understood that when the opening / closing component 30 is in the closed state, the first sound outlet 11 and the end face 121 are not connected. When the opening / closing component 30 is in the open state, the first sound outlet 11 can connect with the end face 121 through the hollow channel 21, thereby enabling the first sound outlet 11 to connect with the external environment.

[0078] Alternatively, the opening / closing component 30 can also be disposed on the housing 10. For example, the opening / closing component 30 can be disposed on one side of the first sound outlet 11, for opening or closing the first sound outlet 11. In this way, the connection between the first sound outlet 11 and the external environment can be opened or closed by opening or closing the first sound outlet 11. Or, for example, the opening / closing component 30 can also be disposed on one side of the end face 121, for opening or closing the end face 121, so that the connection between the first sound outlet 11 and the external environment can be opened or closed by opening or closing the end face 121.

[0079] To more clearly illustrate the specific structure of the electroacoustic transducer 20, the following will provide a detailed description of the specific structure of the electroacoustic transducer 20 in conjunction with the accompanying drawings.

[0080] As is understood, the diaphragm 221 is the main sound-generating component of the electroacoustic transducer 20. Please refer to Figure 8 and Figure 2. Figure 8 is a schematic diagram of the structure of the diaphragm, the first voice coil, and the second voice coil provided in this embodiment. The diaphragm 221 includes an inner folded ring 2211, a first smooth portion 2212, a raised diaphragm top 2213, a second smooth portion 2214, and an outer folded ring 2215 connected in sequence. The inner folded ring 2211 surrounds the hollow channel 21, and the inner folded ring 2211, the raised diaphragm top 2213, and the outer folded ring 2215 all protrude outward relative to the same side of the first smooth portion 2212. It is understood that the inner folded ring 2211, the first smooth portion 2212, the raised diaphragm top 2213, the second smooth portion 2214, and the outer folded ring 2215 are all annular in shape. The first voice coil 222 is connected to the first smooth portion 2212, and the second voice coil 223 is connected to the second smooth portion 2214. Understandably, the first voice coil 222 and the second voice coil 223 are annular structures. The inner folded ring 2211, the raised diaphragm top 2213, and the outer folded ring 2215 all protrude outwards relative to the same side of the first smooth portion 2212. This can be understood as the inner folded ring 2211, the raised diaphragm top 2213, and the outer folded ring 2215 all protruding relative to the same side of the first smooth portion 2212, and the direction of the protrusion is the side of the first smooth portion 2212 away from the first voice coil 222. That is, the protruding structure formed by the inner folded ring 2211, the raised diaphragm top 2213, and the outer folded ring 2215 and the first voice coil 222 are located on both sides of the first smooth portion 2212.

[0081] In this disclosure, by setting the first smooth portion 2212 and the second smooth portion 2214, the first voice coil 222 and the second voice coil 223 can be fixed. Furthermore, the diaphragm 221 is bent to form an inner folded ring 2211, a raised diaphragm top 2213, and an outer folded ring 2215 that protrude outward on the same side relative to the first smooth portion 2212. This allows the inner folded ring 2211, the raised diaphragm top 2213, and the outer folded ring 2215 to cooperate with each other when the diaphragm 221 vibrates, which not only prevents excessive stretching of the diaphragm 221 but also effectively ensures the vibration effect of the diaphragm 221 and improves the audio quality.

[0082] For ease of understanding, a first reference plane perpendicular to the axial direction of the electroacoustic transducer 20 can be defined. In some embodiments, the ratio between the area of ​​the orthographic projection of the raised diaphragm top 2213 onto the first reference plane and the area of ​​the orthographic projection of the entire diaphragm 221 onto the first reference plane is between 0.2 and 0.7. For example, a ratio of 0.2, 0.5, or 0.7 between the area of ​​the orthographic projection of the raised diaphragm top 2213 onto the first reference plane and the area of ​​the orthographic projection of the entire diaphragm 221 onto the first reference plane can effectively improve the high-frequency performance of the electroacoustic transducer 20.

[0083] The inner folding ring 2211, the raised diaphragm top 2213, and the outer folding ring 2215 can have the same protrusion height relative to the first smooth portion 2212. Alternatively, the protrusion heights of the three can be different. For example, the protrusion height of the raised diaphragm top 2213 relative to the first smooth portion 2212 can be greater than the protrusion heights of the inner folding ring 2211 and the outer folding ring 2215 relative to the first smooth portion 2212. This can improve the high-frequency sound output effect of the electroacoustic transducer 20 when it is installed in the headphone 100.

[0084] Furthermore, by combining the inner folding ring 2211 and the outer folding ring 2215, this disclosure can take into account the bass output effect of the electroacoustic transducer 20 when it is placed on the headphone 100, thereby improving the sound output effect of the headphone 100 in multiple dimensions.

[0085] In other embodiments, the inner fold ring 2211, the raised diaphragm top 2213, and the outer fold ring 2215 may protrude in different directions relative to the first smooth portion 2212. For example, the raised diaphragm top 2213 protrudes towards the magnetic circuit system 23 relative to the first smooth portion 2212, while the inner fold ring 2211 and the outer fold ring 2215 protrude away from the magnetic circuit system 23 relative to the first smooth portion 2212. Alternatively, the raised diaphragm top 2213 may protrude away from the magnetic circuit system 23 relative to the first smooth portion 2212, while the inner fold ring 2211 and the outer fold ring 2215 protrude towards the magnetic circuit system 23 relative to the first smooth portion 2212. This improves the structural flexibility of the diaphragm 221, making it suitable for headphones 100 with different structures.

[0086] Optionally, referring to Figure 2, the inner folded ring 2211, the raised diaphragm top 2213, and the outer folded ring 2215 are located on different sides of the first smooth portion 2212 from the first voice coil 222 and the second voice coil 223. Specifically, the inner folded ring 2211, the raised diaphragm top 2213, and the outer folded ring 2215 are located on the side of the first smooth portion 2212 away from the magnetic circuit system 23. This avoids mutual interference between the inner folded ring 2211, the raised diaphragm top 2213, and the outer folded ring 2215 and the magnetic circuit system 23 during vibration, ensuring the vibration effect of the three. Furthermore, the first voice coil 222 and the second voice coil 223 are located on the side of the first smooth portion 2212 closer to the magnetic circuit system 23. This allows the magnetic circuit system 23 to be closer to the first voice coil 222 and the second voice coil 223, and the magnetic field generated by the magnetic circuit system 23 to act more effectively on both, driving their movement.

[0087] In order to further improve the high-frequency performance of the electroacoustic transducer 20, the convex diaphragm top 2213 can be configured as an outwardly convex arc-shaped structure or a planar structure.

[0088] Understandably, when the raised membrane top 2213 vibrates, the high-frequency effect is related to the thickness of the material itself. If the thickness is too thick or too thin, it will affect the high-frequency effect. Based on this, in this embodiment, the thickness of the raised membrane top 2213 is set between 30 micrometers and 70 micrometers. For example, the thickness of the raised membrane top 2213 can be set to 30 micrometers, 50 micrometers or 70 micrometers, so as not to affect the high-frequency effect of the raised membrane top 2213 too much.

[0089] It is also understandable that the high-frequency performance of the electroacoustic transducer 20 is also related to the structure of the outer folding ring 2215 and the inner folding ring 2211.

[0090] Based on this, in this embodiment, the outer loop 2215 can be configured such that the ratio between the area of ​​the orthographic projection of the outer loop 2215 on the first reference plane and the area of ​​the orthographic projection of the entire diaphragm 221 on the first reference plane is between 0.2 and 0.35. For example, a ratio of 0.2, 0.25, or 0.35 can effectively improve the high-frequency performance of the electroacoustic transducer 20. The ratio of the orthographic projection area of ​​the outer loop 2215 on the first reference plane to the area of ​​the orthographic projection of the entire diaphragm 221 on the first reference plane can be set as large as possible, thereby helping to reduce the resonant frequency and improve low-frequency sound quality.

[0091] It is also understandable that the high-frequency effect of the outer folded ring 2215 during vibration is related to the thickness of the material itself. If the thickness is too thick or too thin, it will affect its high-frequency effect. Based on this, in this embodiment, the thickness of the outer folded ring 2215 is set between 35 micrometers and 80 micrometers. For example, the thickness of the outer folded ring 2215 can be set to 35 micrometers, 55 micrometers or 80 micrometers, so as not to affect the high-frequency effect of the outer folded ring 2215 too much.

[0092] In this embodiment, the inner folded ring 2211 can be configured such that the ratio between the area of ​​the orthographic projection of the inner folded ring 2211 on the first reference plane and the area of ​​the orthographic projection of the entire diaphragm 221 on the first reference plane is between 0.1 and 0.2. For example, a ratio of 0.1, 0.15, or 0.2 between the area of ​​the orthographic projection of the inner folded ring 2211 on the first reference plane and the area of ​​the orthographic projection of the entire diaphragm 221 on the first reference plane can effectively improve the high-frequency performance of the electroacoustic transducer 20.

[0093] It is also understandable that the high-frequency effect of the inner folded ring 2211 during vibration is related to the thickness of the material of the inner folded ring 2211 itself. If the thickness is too thick or too thin, it will affect its high-frequency effect. Based on this, in the embodiments of this disclosure, the thickness of the inner folded ring 2211 is set between 35 micrometers and 80 micrometers. For example, the thickness of the inner folded ring 2211 can be set to 35 micrometers, 55 micrometers or 80 micrometers, so as not to affect the high-frequency effect of the inner folded ring 2211 too much.

[0094] The inner folded ring 2211 and the outer folded ring 2215 are both outwardly convex arc-shaped structures. This design allows the inner folded ring 2211, the convex diaphragm top 2213, and the outer folded ring 2215 to work together during diaphragm vibration, preventing excessive stretching of the diaphragm 221 while effectively ensuring its vibration performance and improving audio quality.

[0095] The inner folded ring 2211 and the outer folded ring 2215 may have a textured structure, or both of them may have a textured structure. Understandably, the textured structure can form a reinforcing rib structure, thereby enhancing the rigidity of the diaphragm 221, reducing the deformation of the diaphragm 221 during vibration, and thus reducing distortion in the low-frequency range.

[0096] Understandably, in order to fix the diaphragm 221, please refer to Figure 9 in conjunction with Figures 1 and 2. Figure 9 is a first exploded view of the electroacoustic transducer provided in the embodiment of this disclosure. The electroacoustic transducer 20 also includes a frame 24, which includes an annular inner frame wall 241 and an annular outer frame wall 242. The inner frame wall 241 defines a hollow channel 21, and the outer frame wall 242 surrounds the inner frame wall 241.

[0097] It is also understandable that the basin stand 24 can be made of one or more of the following materials: metal, plastic or resin.

[0098] As shown in Figures 1, 2, and 8, the diaphragm 221 further includes a first connecting portion 2216 and a second connecting portion 2217. The first connecting portion 2216 is connected to the inner folding ring 2211 and surrounds the hollow channel 21, while the second connecting portion 2217 is connected to the outer folding ring 2215. It is understood that both the first connecting portion 2216 and the second connecting portion 2217 are annular structures. The first connecting portion 2216 is connected to the inner sidewall 241 of the frame, and the second connecting portion 2217 is connected to the outer sidewall 242 of the frame. In this way, the diaphragm 221 can be fixedly connected to the frame 24.

[0099] Since the inner wall of the frame 24 defines the hollow channel 21, it is understandable that the diameter of the inner wall 241 determines the cross-sectional area of ​​the hollow channel 21. A larger cross-sectional area of ​​the hollow channel 21 results in better permeability of the electroacoustic transducer 20. Therefore, in some embodiments, as shown in Figure 2, the ratio between the minimum diameter D2 of the inner wall 241 and the maximum diameter D1 of the outer wall 242 is set between 0.1 and 0.5. Thus, with a fixed size for the frame 24 itself, the diameter of the inner wall 241 can be increased as much as possible without significantly reducing the strength of the frame 24, which means the cross-sectional area of ​​the hollow channel 21 can be increased as much as possible, thereby improving the permeability of the electroacoustic transducer 20.

[0100] Optionally, the ratio between the minimum diameter D2 of the inner wall 241 of the basin stand and the maximum diameter D1 of the outer wall 242 of the basin stand is set between 0.2 and 0.4, or between 0.2 and 0.5. Alternatively, the ratio between the minimum diameter D2 of the inner wall 241 of the basin stand and the maximum diameter D1 of the outer wall 242 of the basin stand is set to 0.3, 0.35, 0.4, or 0.45.

[0101] It is understandable that the frame 24 is a component that supports the diaphragm 221, and the first connecting part 2216 and the second connecting part 2217 of the diaphragm 221 can be directly connected to the frame 24.

[0102] In some embodiments, to improve the connection strength between the diaphragm 221 and the frame 24, as shown in Figures 2 and 8, the electroacoustic transducer 20 may further include a first fixing ring 25 and a second fixing ring 26. The first fixing ring 25 fixes the first connecting portion 2216 to the inner sidewall 241 of the frame, that is, the first connecting portion 2216 is fixedly connected to the inner sidewall 241 of the frame through the first fixing ring 25. The second fixing ring 26 fixes the second connecting portion 2217 to the outer sidewall 242 of the frame, that is, the second connecting portion 2217 is fixedly connected to the outer sidewall 242 of the frame through the second fixing ring 26. Thus, with the connection and fixation of the first fixing ring 25 and the second fixing ring 26, a stable connection is achieved between the diaphragm 221 and the frame 24.

[0103] The first fixing ring 25 and the second fixing ring 26 can be made of steel. For example, both the first fixing ring 25 and the second fixing ring 26 can be steel rings.

[0104] Understandably, since the maximum outer diameter of the second fixing ring 26 is related to the maximum outer diameter of the outer wall 242 of the basin frame, the larger the maximum outer diameter of the outer wall 242 of the basin frame, the larger the maximum outer diameter of the second fixing ring 26 can be. Since the diaphragm 221 is connected to the outer wall 242 of the basin frame through the second fixing ring 26, the larger the maximum outer diameter of the second fixing ring 26, the larger the maximum outer diameter of the diaphragm 221 can be. In this case, the frequency response of the diaphragm 221 will be better. Based on this, in order to make the diameter of the diaphragm 221 larger, as shown in Figure 2, the ratio between the maximum outer diameter d1 of the second fixing ring 26 and the maximum diameter D1 of the outer wall 242 of the basin frame is set between 0.7 and 1. In this way, the diameter of the diaphragm 221 can be made larger, which can improve the frequency response of the diaphragm 221.

[0105] Optionally, the ratio between the maximum outer diameter d1 of the second fixing ring 26 and the maximum diameter D1 of the outer wall 242 of the basin frame can be between 0.8 and 1, or between 0.9 and 1. Alternatively, the ratio between the maximum outer diameter d1 of the second fixing ring 26 and the maximum diameter D1 of the outer wall 242 of the basin frame can be 0.75, 0.85, or 0.95.

[0106] Preferably, the ratio between the maximum outer diameter d1 of the second fixing ring 26 and the maximum diameter D1 of the outer wall 242 of the frame is 1. At this time, the diameter of the diaphragm 221 can be made to the maximum, and the frequency response effect is optimal.

[0107] It is also understandable that, since the diaphragm 221 is also connected to the inner wall 241 of the frame via the first fixing ring 25, and the first fixing ring 25 surrounds the hollow channel 21 defined by the inner wall 241 of the frame, the minimum inner diameter of the first fixing ring 25 is related to the cross-sectional area of ​​the hollow channel 21. In order to increase the cross-sectional area of ​​the hollow channel 21, the minimum inner diameter of the first fixing ring 25 needs to be made larger. In this disclosure, as shown in Figure 2, the ratio between the minimum inner diameter d2 of the first fixing ring 25 and the maximum diameter D1 of the outer wall 242 of the frame is set between 0.1 and 0.5. At this time, the first fixing ring 25 has a more suitable minimum inner diameter, thereby ensuring the transparency of the electroacoustic transducer 20.

[0108] Optionally, the ratio between the minimum inner diameter d2 of the first retaining ring 25 and the maximum diameter D1 of the outer wall 242 of the basin frame is set between 0.2 and 0.4, or between 0.2 and 0.5. Alternatively, the ratio between the minimum inner diameter d2 of the first retaining ring 25 and the maximum diameter D1 of the outer wall 242 of the basin frame is set to 0.3, 0.35, 0.4, or 0.45.

[0109] It should be noted that in the electroacoustic transducer 20, the magnetic circuit system 23 has a magnetic gap, and at least a portion of the first voice coil 222 and at least a portion of the second voice coil 223 are located in the magnetic gap. Thus, the first voice coil 222 and the second voice coil 223 are driven by the magnetic circuit system 23 to vibrate the diaphragm 221. That is, the vibration effect of the diaphragm 221 is related to the magnetic circuit system 23. Based on this, in order to increase the driving force and sound pressure level of the electroacoustic transducer 20, in this disclosure, the first voice coil 222 and the second voice coil 223 are driven by a dual magnetic circuit system 23. Please refer to Figures 2 and 9. The magnetic circuit system 23 includes a second magnetic element 2312, a third magnetic element 2313, and a fourth magnetic element 2314 respectively disposed on the basket frame 24. The second magnetic element 2312 surrounds the inner sidewall 241 of the basket frame, the third magnetic element 2313 surrounds the second magnetic element 2312, and the fourth magnetic element 2314 surrounds the third magnetic element 2313. It can be understood that the second magnetic element 2312, the third magnetic element 2313, and the fourth magnetic element 2314 form a ring structure. The second magnetic element 2312 and the third magnetic element 2313 are radially spaced to form a third magnetic gap 2323, and the third magnetic element 2313 and the fourth magnetic element 2314 are radially spaced to form a fourth magnetic gap 2324. One end of the first voice coil 222 extends to the third magnetic gap 2323, and one end of the second voice coil 223 extends to the fourth magnetic gap 2324.

[0110] It is understandable that the third magnetic gap 2323 and the fourth magnetic gap 2324 have magnetic fields with a certain magnetic field direction. Therefore, the voice coil located in the magnetic gap can move under the action of the magnetic field and drive the diaphragm 221 to vibrate.

[0111] In some embodiments, the entirety of the first voice coil 222 and the entirety of the second voice coil 223 can be located within the magnetic gap. It is understood that, along the thickness direction of the electroacoustic transducer 20, the entirety of the first voice coil 222 can extend into the third magnetic gap 2323, and the entirety of the second voice coil 223 can extend into the fourth magnetic gap 2324. This ensures that the magnetic field within the third magnetic gap 2323 effectively acts on the first voice coil 222, and the magnetic field within the fourth magnetic gap 2324 effectively acts on the second voice coil 223, thereby facilitating the vibration of the diaphragm 221 by the entirety of the first voice coil 222 and the second voice coil 223, improving the sound output effect of the electroacoustic transducer 20. Furthermore, having the entire voice coil located within the magnetic gap helps reduce the thickness of the electroacoustic transducer 20, which is beneficial for its miniaturization.

[0112] In other embodiments, portions of the first voice coil 222 and the second voice coil 223 may be located within the magnetic gap. It is understood that, along the thickness direction of the electroacoustic transducer 20, a portion of the end of the first voice coil 222 may extend into the third magnetic gap 2323, and a portion of the end of the second voice coil 223 may extend into the fourth magnetic gap 2324. This reduces the difficulty of assembling and aligning the voice coils and various magnetic components. Furthermore, it avoids mutual interference and wear between the magnetic components and the voice coil when the voice coil is located within the magnetic gap. Therefore, the structural arrangement of this embodiment helps to improve the structural stability of the electroacoustic transducer 20.

[0113] The vibration effect of the electroacoustic transducer 20 is related to the size of the magnetic gap. Therefore, to effectively improve the low-frequency harmonic distortion problem of the electroacoustic transducer 20, this disclosure sets the sizes of the third magnetic gap 2323 and the fourth magnetic gap 2324 between 0.5 mm and 1.3 mm to facilitate the improvement of low-frequency harmonic distortion. For example, the sizes of the third magnetic gap 2323 and the fourth magnetic gap 2324 can be set to 0.5 mm, 0.8 mm, 1.1 mm, or 1.3 mm. Preferably, the sizes of the third magnetic gap 2323 and the fourth magnetic gap 2324 are set to 0.5 mm.

[0114] It is also understood that, in order to improve the magnetic conductivity, as shown in Figures 2 and 9, the magnetic circuit system 23 may further include a first magnetic conductive element 2331, a second magnetic conductive element 2332, and a third magnetic conductive element 2333, wherein the magnetic conductive element may also be referred to as a washer. Exemplarily, the first magnetic conductive element 2331, the second magnetic conductive element 2332, and the third magnetic conductive element 2333 form a ring structure. The first magnetic conductive element 2331 is disposed on the side of the second magnetic element 2312 facing the diaphragm 221, the second magnetic conductive element 2332 is disposed on the side of the third magnetic element 2313 facing the diaphragm 221, and the third magnetic conductive element 2333 is disposed on the side of the fourth magnetic element 2314 facing the diaphragm 221. For example, the first magnetic conductive element 2331 can be fixed to the surface of the second magnetic element 2312 facing the diaphragm 221 by adhesive, the second magnetic conductive element 2332 can be fixed to the surface of the third magnetic element 2313 facing the diaphragm 221 by adhesive, and the third magnetic conductive element 2333 can be fixed to the surface of the fourth magnetic element 2314 facing the diaphragm 221 by adhesive.

[0115] Understandably, the first magnetic conductive element 2331, the second magnetic conductive element 2332, and the third magnetic conductive element 2333 can be made of magnetically conductive material. The second magnetic element 2312, the third magnetic element 2313, and the fourth magnetic element 2314 can be made of magnetic material. For example, the magnetic material can be a magnet.

[0116] In other embodiments, to reduce costs, the first voice coil 222 and the second voice coil 223 can be driven by a single magnetic circuit system 23. Please refer to Figures 10 and 11. Figure 10 is a cross-sectional view of an electroacoustic transducer provided in another embodiment of this disclosure, and Figure 11 is a second exploded view of an electroacoustic transducer provided in an embodiment of this disclosure. In this case, the magnetic circuit system 23 includes a first magnetic element 2311, which is disposed on the frame 24 and surrounds the inner sidewall 241 of the frame. A first magnetic gap 2321 and a second magnetic gap 2322 are spaced apart between the first magnetic element 2311 and the frame 24. The first magnetic gap 2321 surrounds the inner sidewall 241 of the frame, and the second magnetic gap 2322 surrounds the outer periphery of the first magnetic gap 2321. For example, the first magnetic element 2311 is spaced apart from the inner sidewall 241 of the basket to form a first magnetic gap 2321, and the first magnetic element 2311 is spaced apart from the outer sidewall 242 of the basket to form a second magnetic gap 2322. One end of the first voice coil 222 extends to the first magnetic gap 2321, and one end of the second voice coil 223 extends to the second magnetic gap 2322.

[0117] It is understandable that the first magnetic gap 2321 and the second magnetic gap 2322 have magnetic fields with a certain magnetic field direction. Therefore, the voice coil located in the magnetic gap can move under the action of the magnetic field and drive the diaphragm 221 to vibrate.

[0118] The vibration effect of the electroacoustic transducer 20 is related to the size of the magnetic gap. Therefore, to effectively improve the low-frequency harmonic distortion problem of the electroacoustic transducer 20, in this embodiment, the sizes of the first magnetic gap 2321 and the second magnetic gap 2322 are set between 0.5 mm and 1.3 mm to facilitate the improvement of low-frequency harmonic distortion. For example, the sizes of the first magnetic gap 2321 and the second magnetic gap 2322 can be set to 0.5 mm, 0.8 mm, 1.1 mm, or 1.3 mm. Preferably, the sizes of the first magnetic gap 2321 and the second magnetic gap 2322 are set to 0.5 mm.

[0119] It is also understood that, in order to improve the magnetic conductivity, the magnetic circuit system 23 may further include a fourth magnetic conductive element 2334, which may also be referred to as a washer. Exemplarily, the fourth magnetic conductive element 2334 has a ring-shaped structure and is disposed on the side of the first magnetic element 2311 facing the diaphragm 221. For example, the fourth magnetic conductive element 2334 can be fixed to the surface of the first magnetic element 2311 facing the diaphragm 221 by adhesive bonding.

[0120] Understandably, the fourth magnetic component 2334 can be made of a magnetic material. The first magnetic component 2311 can be made of a magnetic material. For example, the magnetic material can be a magnet.

[0121] It is also understood that the frame 24 serves as a supporting component for the electroacoustic transducer 20. In some embodiments, please refer to Figures 2 and 4. The frame 24 may also include a frame bottom wall 243. The frame bottom wall 243 and the diaphragm 221 are arranged opposite each other in the axial direction of the electroacoustic transducer 20. The magnetic circuit system 23 is supported on the frame bottom wall 243, that is, the frame bottom wall 243 plays the role of supporting the magnetic circuit system 23.

[0122] In some embodiments, referring to Figures 2 and 4, to achieve the tuning function, the frame 24 is also provided with a rear tuning hole 244, which communicates with the magnetic gap of the magnetic circuit system 23. For example, the rear tuning hole 244 can be provided on the bottom wall 243 of the frame. It is understood that a rear sound outlet hole 13 communicating with the rear tuning hole 244 can also be provided on the housing 10 of the earphone 100. For example, referring to Figure 3, the housing 10 has a rear sound outlet hole 13 located on the side of the housing 10 away from the ear 200. The tuning function can be achieved through the interaction of the rear tuning hole 244 and the rear sound outlet hole 13.

[0123] The above is a detailed description of the structure of the electroacoustic transducer 20. The structure of the earphone 100 will be further explained below with reference to the attached drawings.

[0124] In some embodiments, referring to Figure 3, in order to better cover the earphone 100 to the ear 200, a covering cavity 40 is formed on the side of the earphone 100 facing the ear 200. The first sound outlet 11 communicates with the covering cavity 40. When the earphone 100 is worn, the covering cavity 40 covers the ear 200. It can be understood that at this time, the sound signal generated by the diaphragm 221 of the electroacoustic transducer 20 can be transmitted through the first sound outlet 11 to the covering cavity 40, and further transmitted to the ear canal, and then enters the ear canal.

[0125] For example, referring to Figure 3, the headphones 100 may include ear pads 50, which are disposed around the side of the housing 10 facing the ear 200, defining a covering cavity 40. When the headphones 100 are worn, the ear pads 50 conform to the head, thereby covering the ear 200. The ear pads 50 may be made of a flexible material to improve wearing comfort.

[0126] Example 2

[0127] The present disclosure will now be described in detail with reference to embodiments.

[0128] Please refer to Figure 12, which is a schematic diagram of the ear structure. Figure 12 shows some of the physiological locations of the ear. The user's ear 200 may include the helix 210, scaphoid 220, antihelix 230, triangular fossa 240, concha 250, ear canal 260, tragus 270, antitragus 280, and earlobe 290. The concha 250 may include the cymba conchae 251 and the concha cavity 252. The ear canal 260 may also be referred to as the opening of the external auditory meatus or external auditory canal.

[0129] It is understood that the headphones 100 provided in this embodiment can be either over-ear headphones or on-ear headphones. When worn on the ear 200, the over-ear headphones cover the ear 200, enclosing the entire ear 200 within the cavity formed by the headphones and the head, providing good sealing. On-ear headphones differ slightly from over-ear headphones in that they fit snugly against the auricle 210 of the ear 200. Relatively speaking, over-ear headphones offer better sealing than on-ear headphones. However, both over-ear and on-ear headphones provide better sealing than in-ear headphones, thus offering better sound quality.

[0130] Please refer to Figures 13 and 14. Figure 13 is a structural schematic diagram of the headphones worn on the ear from a first perspective, and Figure 14 is a structural schematic diagram of the headphones worn on the ear from a second perspective. In the related technology, when the over-ear headphones 100a are worn on the ear, the ear is completely covered and sealed in a relatively small space. When the ear is in this sealed environment for a long time, the temperature in the space is likely to rise, and bacteria are likely to grow, resulting in ear discomfort. Understandably, the on-ear headphones in the related technology, which also cover the ear, will have the same problem as the over-ear headphones 100a.

[0131] Based on this, please refer to Figures 15 and 16. Figure 15 is a first cross-sectional view of the earphones provided in this embodiment when worn in the ear, and Figure 16 is a second cross-sectional view of the earphones provided in this embodiment when worn in the ear. It is understood that the opening / closing component 30 in Figure 15 is in the open state, and in Figure 16 it is in the closed state. This embodiment provides an earphone 100, including a housing 10, an electroacoustic transducer 20, and an opening / closing component 30. The electroacoustic transducer 20 is disposed within the housing 10, and the electroacoustic transducer 20 has a hollow channel 21 extending along its own axial direction. It is understood that because the electroacoustic transducer 20 has a through hollow channel 21, the electroacoustic transducer 20 is approximately annular in structure.

[0132] The earphone 100 has a first sound outlet 11 on its housing 10 facing the ear 200. When the earphone 100 is worn on the ear 200, the sound signal emitted by the electroacoustic transducer 20 can be transmitted through the first sound outlet 11 to the ear canal 260 and then into the ear canal. The first sound outlet 11 is connected to the hollow channel 21. The housing 10 includes an outer wall 12, which is positioned opposite to the electroacoustic transducer 20 in the axial direction. The outer wall 12 has an end face 121 that connects the hollow channel 21 to the external environment. Thus, because the first sound outlet 11 is connected to the hollow channel 21, it can communicate with the external environment through the hollow channel 21 and the end face 121, thereby enabling airflow and sound transmission.

[0133] The opening and closing component 30 is used to open or close the connection between the first sound outlet 11 and the external environment.

[0134] The opening / closing component 30 can be disposed on the housing 10. The location of the opening / closing component 30 on the housing 10 can be as follows:

[0135] In a first feasible implementation, the opening / closing component 30 is disposed at the hollow channel 21 of the electroacoustic transducer 20, and is used to open or close the hollow channel 21. It is understood that when the opening / closing component 30 is in the closed state, the first sound outlet 11 and the end face 121 are not connected. When the opening / closing component 30 is in the open state, the first sound outlet 11 can connect with the end face 121 through the hollow channel 21, thereby enabling the first sound outlet 11 to connect with the external environment.

[0136] As a second feasible implementation, the opening and closing component 30 can be disposed on one side of the first sound outlet 11 to open or close the first sound outlet 11. In this way, the connection between the first sound outlet 11 and the external environment can be opened or closed by opening or closing the first sound outlet 11, that is, the connection between the fourth cavity 40 and the external environment can be opened or closed.

[0137] As a third possible implementation, the opening and closing component 30 can also be disposed on one side of the end face 121 for opening or closing the end face 121. In this way, the connection between the first sound outlet 11 and the external environment can be opened or closed by opening or closing the end face 121, that is, the connection between the fourth cavity 40 and the external environment can be opened or closed.

[0138] Understandably, the headphones 100 provided in this embodiment of the present disclosure have a hollow channel 21 on the electroacoustic transducer 20 that communicates with the first sound outlet 11, and an end face 121 on the outer side wall 12 of the housing 10 that communicates with the hollow channel 21. Furthermore, an opening / closing component 30 for opening or closing the hollow channel 21 is provided. When the opening / closing component 30 is closed, it provides a sealed listening environment for the ear 200, satisfying the user's need for an immersive experience. When the opening / closing component 30 is open, the first sound outlet 11 communicates with the end face 121 through the hollow channel 21, enabling the fourth cavity 40 to communicate with the external environment. This provides an open listening environment for the ear 200, allowing the user to listen to music while also hearing external sounds, satisfying different listening needs. It also dissipates heat inside the headphones 100, keeping the ear 200 in a comfortable state. Furthermore, by adopting the method of setting a hollow channel 21 in the electroacoustic transducer 20, the path length of airflow or sound flowing between the first sound outlet 11 and the end face 121 can be minimized, effectively improving the transparency of the headphones 100. Moreover, by setting the end face 121 on the outer wall 12 opposite to the electroacoustic transducer 20, the distance between the end face 121 and the hollow channel 21 can be further reduced, further reducing the path length of airflow or sound flowing between the first sound outlet 11 and the end face 121, thereby further improving the transparency of the headphones 100.

[0139] It is understood that the shapes of the first sound hole 11 and the end face 121 can be circular, but are not limited to circular. They can also include one or more of the following shapes: elliptical, racetrack-shaped, triangular, rectangular, polygonal, or other complex shapes with decorative features. This disclosure does not impose any limitations on these shapes.

[0140] In order to improve the transparency of the headphone 100, the size of the first sound outlet 11, the end face 121 and the hollow channel 21 can be made as large as possible. That is, the larger the cross-sectional area of ​​the first sound outlet 11, the end face 121 and the hollow channel 21, the better the transparency of the headphone 100.

[0141] For example, the minimum cross-sectional area of ​​the first sound outlet 11 is greater than or equal to 15 square millimeters. This effectively improves the transparency of the earphone 100 and also improves the quality of sound transmission. More preferably, the minimum cross-sectional area of ​​the first sound outlet 11 is greater than or equal to 25 square millimeters, and even more preferably, the minimum cross-sectional area of ​​the first sound outlet 11 is greater than or equal to 40 square millimeters.

[0142] For ease of understanding, a first reference plane perpendicular to the central axis of the electroacoustic transducer 20 can be constructed. In some embodiments, the orthographic projection of the first sound outlet 11 onto the first reference plane at least partially overlaps with the orthographic projection of the hollow channel 21 onto the first reference plane. This minimizes the radial distance between the first sound outlet 11 and the hollow channel 21, effectively shortening the path between them and further improving the transparency of the earphone 100.

[0143] Since the first sound outlet 11 also serves to emit sound, in some embodiments, the area of ​​the first sound outlet 11 projected onto the first reference plane can be larger than the area of ​​the hollow channel 21 projected onto the first reference plane. This ensures sound quality while effectively improving the transparency of the headphones 100.

[0144] It is understood that the electroacoustic transducer 20 includes a ring-shaped diaphragm 23 surrounding the hollow channel 21. The sound signal generated when the diaphragm 23 vibrates can be transmitted to the human ear 200 through the first sound outlet 11. To improve the sound quality of the first sound outlet 11, the orthographic projection of the first sound outlet 11 on the first reference plane at least partially overlaps with the orthographic projection of the diaphragm 23 on the first reference plane. In this way, the sound signal generated by the vibration of the diaphragm 23 can be better transmitted through the first sound outlet 11.

[0145] In some embodiments, considering that the area of ​​the first sound outlet 11 is relatively large, and the diaphragm 23 of the electroacoustic transducer 20 may be touched by the user, the headphone 100 may further include a protective member with a mesh structure, wherein the protective member is disposed at the first sound outlet 11. Thus, the electroacoustic transducer 20 can be protected by the protective member. Exemplarily, the protective member may be a metal mesh, foam, mesh fabric, or plastic support, etc. For example, a metal mesh, foam, mesh fabric, or plastic support can be added at the first sound outlet 11 to protect the electroacoustic transducer 20. The metal mesh, foam, mesh fabric, or plastic support can be fixed to the first sound outlet 11 by adhesive bonding, hot melting, injection molding, ultrasonic connection, or other processes. For example, in some embodiments, the metal mesh, mesh fabric, or plastic support can be fixedly connected to the first sound outlet 11 by injection molding.

[0146] In some embodiments, to better accommodate the earphone 100 around the ear 200, as shown in Figure 15, a fourth cavity 40 is formed on the side of the earphone 100 facing the ear 200. The first sound outlet 11 communicates with the fourth cavity 40. When the earphone 100 is worn, the fourth cavity 40 covers the ear 200. Understandably, at this time, the sound signal generated by the diaphragm 23 of the electroacoustic transducer 20 can be transmitted through the first sound outlet 11 to the fourth cavity 40, and further to the ear canal 260, and then into the ear canal.

[0147] For example, referring to Figure 15, the headphones 100 may include ear pads 50, which are disposed around the side of the housing 10 facing the ear 200, defining a fourth cavity 40. When the headphones 100 are worn, the ear pads 50 conform to the head, thereby covering the ear 200. The ear pads 50 may be made of a flexible material to improve wearing comfort.

[0148] Furthermore, to improve the conductivity between the ear 200 and the external environment when wearing the headphones 100, a second reference plane is established using the three regions of the ear 200: the tragus 270, the antitragus 280, and the antihelix 230. The projection of the first sound outlet 11 and / or the end face 121 onto the second reference plane along the coronal axis is located on or covers the area formed by the projections of the cymba conchae 251, the antihelix 230, the antitragus 280, and the tragus 270 onto the second reference plane along the coronal axis. More preferably, the projection of the first sound outlet 11 and / or the end face 121 onto the second reference plane along the coronal axis is located in the area formed by the projection of the conchae cavity 252 onto the second reference plane along the coronal axis.

[0149] It is also understandable that when the earphone 100 is worn on the head, the ear pad 50 of the earphone 100 fits against the head, and the outer periphery of the ear pad 50 fitting against the head forms a ring. The orthographic projection of the first sound outlet 11 and / or the end face 121 on the head is located in the region where the ring is reduced inward by 10 mm to 15 mm, for example, the orthographic projection of the first sound outlet 11 and / or the end face 121 on the head is located in the region where the ring is reduced inward by 10 mm, 12 mm, or 15 mm. Further, the orthographic projection of the first sound outlet 11 and / or the end face 121 on the head is located in the region where the ring is reduced inward by 16 mm to 25 mm, for example, the orthographic projection of the first sound outlet 11 and / or the end face 121 on the head is located in the region where the ring is reduced inward by 16 mm, 20 mm, or 25 mm. Furthermore, the orthographic projection of the first sound outlet 11 and / or the end face 121 on the head is located in the region after the annular shape is reduced inward by 26 mm to 35 mm, for example, the orthographic projection of the first sound outlet 11 and / or the end face 121 on the head is located in the region after the annular shape is reduced inward by 26 mm, 30 mm or 35 mm.

[0150] As you can understand, please refer to Figure 17, which is a schematic diagram of the projection of the hollow channel, ear hole, and end face 121 onto the second reference plane H along the coronal axis direction provided in this embodiment of the present disclosure. The projection of the hollow channel 21 onto the second reference plane H along the coronal axis direction and the projection of the ear hole 260 of the ear 200 onto the second reference plane H along the coronal axis direction have a first minimum distance D1. The projection of the end face 121 onto the second reference plane H along the coronal axis direction and the projection of the ear hole 260 onto the second reference plane H along the coronal axis direction have a second minimum distance D2. To further improve the openness of the ear 200 to the outside world, the first minimum distance D1 is less than or equal to the second minimum distance D2. As you can understand, according to the above settings, when the earphone 100 is in the open state, that is, when the opening / closing component 30 is open, the tragus 270 and ear hole 260 of the ear 200 can be seen through the first sound outlet 11, the end face 121, and the hollow channel 21, allowing the ear 200 to communicate with the outside world.

[0151] It should be noted that the opening / closing component 30, as a component for opening or closing the hollow channel 21, is mainly used for opening or closing the hollow channel 21. This disclosure does not impose specific limitations on its structure; it only needs to be able to achieve the opening or closing of the hollow channel 21. For example, the opening / closing component 30 can be a shutter assembly similar to a "shutter," which may include multiple blades. These blades can move radially relative to the hollow channel 21. The blades can move closer to each other to achieve a closing function, and they can move further apart to achieve an opening function. For example, a perspective view of the earphone 100 in its open state is shown in Figure 18, and a perspective view of the earphone 100 in its sealed state is shown in Figure 19.

[0152] In some embodiments, the opening and closing component 30 is installed on the housing 10. The opening and closing component 30 can be connected to a linkage mechanism (not shown) disposed on the housing 10. One end of the linkage mechanism is located outside the housing 10, and the other end of the linkage mechanism is connected to the opening and closing component 30, such as to the blade of the opening and closing component 30. The user drives the linkage mechanism to open or close the opening and closing component 30, thereby switching the open state and sealed state of the earphone 100.

[0153] In other embodiments, the linkage mechanism can be connected to a motor, which drives the linkage mechanism to open or close the opening and closing component 30. For example, the motor can receive instructions from the main control chip of the earphone 100 to control the opening and closing of the opening and closing component 30.

[0154] The above is an introduction to the first sound outlet 11 of the headphone 100 and its related structures. In order to more clearly explain other structures of the headphone 100, such as the structure between the hollow channel 21 and the end face 121, the following will be described in detail with reference to the accompanying drawings.

[0155] Please refer to Figure 15. The housing 10 has a first cavity 13, which is located between the electroacoustic transducer 20 and the end face 121. At this time, the outer wall 12 of the earphone 100 and the electroacoustic transducer 20 are separately arranged. The end face 121 on the outer wall 12 is connected to the hollow channel 21 through the first cavity 13. It can be understood that when the opening and closing assembly 30 is opened, the hollow channel 21 is connected to the first cavity 13, and the first cavity 13 is connected to the end face 121. Thus, the hollow channel 21 can be connected to the end face 121 through the first cavity 13, that is, the first cavity 13 serves to connect the hollow channel 21 and the end face 121.

[0156] For example, referring to Figure 15, the housing 10 includes an inner sidewall 14, an outer sidewall 12, and a connecting wall 15. The inner sidewall 14 and the outer sidewall 12 are disposed opposite each other in the axial direction of the electroacoustic transducer 20. The connecting wall 15 connects the inner sidewall 14 and the outer sidewall 12. The inner sidewall 14, the outer sidewall 12, and the connecting wall 15 together define a first cavity 13. A first sound outlet 11 is disposed on the inner sidewall 14. It is understood that when the earphone 100 is worn on the ear 200, the inner sidewall 14 is located on the side closer to the ear 200.

[0157] It is also understood that, in the above embodiments, the connection between the hollow channel 21 and the end face 121 is achieved through the first cavity 13. To improve the permeability between the hollow channel 21 and the end face 121, the shorter the channel path between the end face 121 and the first cavity 13, the better. Preferably, the outer wall 12 with the end face 121 can be fitted to the electroacoustic transducer 20. In this case, the end face 121 and the hollow channel 21 of the electroacoustic transducer 20 do not need to be connected through the first cavity 13. Instead, the end face 121 is directly connected to the hollow channel 21 of the electroacoustic transducer 20, thereby further improving the permeability between the hollow channel 21 and the end face 121.

[0158] It should be noted that the opening / closing component 30 can also be located in the first cavity 13 of the housing 10, at the connection between the hollow channel 21 and the end face 121, for opening or closing the connection between the end face 121 and the hollow channel 21. In this way, by controlling the connection or disconnection of the end face 121 and the hollow channel 21, the connection or disconnection between the first sound outlet 11 and the external environment can be controlled. By placing the opening / closing component 30 in the first cavity 13, the housing 10 can provide protection for the opening / closing component 30, mitigating or preventing wear on the opening / closing component 30.

[0159] In some embodiments, the orthographic projection of the hollow channel 21 onto the outer side wall 12 of the housing 10 at least partially overlaps with the end face 121 on the outer side wall 12. Alternatively, the orthographic projection of the hollow channel 21 onto the outer side wall 12 of the housing 10 does not overlap with the end face 121 on the outer side wall 12 at all.

[0160] For example, the orthographic projection of the hollow channel 21 onto the outer side wall 12 of the housing 10 can overlap with the end face 121 on the outer side wall 12. In this way, the hollow channel 21 and the end face 121 can be directly connected along the axial direction of the electroacoustic transducer 20, thereby improving the connection effect between the two and enhancing the transparency of the headphones.

[0161] For example, the orthographic projection of the hollow channel 21 onto the outer wall 12 of the housing 10 can be completely non-overlapping with the end face 121 on the outer wall 12. That is, the orthographic projection of the hollow channel 21 onto the outer wall 12 of the housing 10 and the end face 121 on the outer wall 12 can be staggered. In this way, both the various positional arrangements of the end face 121 on the outer wall 12 and the connectivity between the hollow channel 21 and the end face 121 can be satisfied, thereby improving the structural flexibility of the headphones.

[0162] For example, the radial distance between the central axis of the end face 121 and the central axis of the hollow channel 21 is between 0 mm and 36 mm, i.e., greater than or equal to 0 mm and less than or equal to 36 mm. Thus, the channel path between the end face 121 and the hollow channel 21 can be set as short as possible to improve the permeability between the hollow channel 21 and the end face 121. It is understood that the smaller the distance between the central axis of the end face 121 and the central axis of the hollow channel 21, the better. More preferably, the distance between the central axis of the end face 121 and the central axis of the hollow channel 21 is between 0 mm and 20 mm, i.e., greater than or equal to 0 mm and less than or equal to 20 mm. Even more preferably, the distance between the central axis of the end face 121 and the central axis of the hollow channel 21 is between 0 mm and 5 mm, i.e., greater than or equal to 0 mm and less than or equal to 5 mm. The distance between the central axis of the end face 121 and the central axis of the hollow channel 21 can be set according to specific circumstances. For example, the distance between the central axis of the end face 121 and the central axis of the hollow channel 21 in the radial direction of the electroacoustic transducer 20 can be 36 mm, 20 mm, 10 mm, 5 mm or 0 mm. It can be understood that when the radial distance between the central axis of the end face 121 and the central axis of the hollow channel 21 is 0 mm, the end face 121 and the hollow channel 21 are coaxial, and the transparency between the hollow channel 21 and the end face 121 is optimal.

[0163] In some embodiments, to further improve the permeability between the hollow channel 21 and the end face 121, the axial distance between the end face 121 and the electroacoustic transducer 20 should be as short as possible. For example, referring to FIG15, the electroacoustic transducer 20 includes a first surface A facing the end face 121, and the axial distance d1 between the end face 121 and the first surface A in the electroacoustic transducer 20 is greater than or equal to 0.5 mm and less than or equal to 10 mm. For example, the axial distance d1 between the end face 121 and the first surface A can be 0.5 mm, 1 mm, 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, etc.

[0164] Specifically, as shown in Figure 15, the electroacoustic transducer 20 may include a frame 22, a diaphragm 23, a voice coil (not shown), and a magnetic element 24. The diaphragm 23 is disposed on the frame 22, and the diaphragm 23 and the frame 22 surround the hollow channel 21. The magnetic element 24 is disposed on the frame 22 and surrounds the hollow channel 21. The magnetic element 24 forms the magnetic circuit system of the electroacoustic transducer 20, and the diaphragm 23 and the voice coil form the vibration system of the electroacoustic transducer 20. One end of the voice coil is fixedly connected to the diaphragm 23, and the other end extends to the magnetic gap of the magnetic system. Understandably, the magnetic system can drive the voice coil to move, thereby causing the diaphragm 23 to vibrate and produce sound.

[0165] In some embodiments, to ensure the unobstructed communication between the headphones 100 and the external environment, the size of the hollow channel 21 of the electroacoustic transducer 20 can be made as large as possible; that is, the larger the cross-sectional area of ​​the hollow channel 21, the better the transparency of the headphones 100. For example, the minimum cross-sectional area of ​​the hollow channel 21 is greater than or equal to 5 square millimeters. More preferably, the minimum cross-sectional area of ​​the hollow channel 21 is greater than or equal to 10 square millimeters; even further, the minimum cross-sectional area of ​​the hollow channel 21 is greater than or equal to 20 square millimeters.

[0166] It is also understandable that the size of the end face 121 can be made as large as possible, that is, the larger the cross-sectional area of ​​the end face 121, the better the transparency of the earphone 100. Among them, the minimum cross-sectional area of ​​the end face 121 can be greater than or equal to 15 square millimeters, more preferably, the minimum cross-sectional area of ​​the end face 121 can be greater than or equal to 25 square millimeters, and even more preferably, the minimum cross-sectional area of ​​the end face 121 can be greater than or equal to 40 square millimeters.

[0167] In some embodiments, to better facilitate airflow between the hollow channel 21 and the end face 121, please refer to FIG20, which is a third cross-sectional view of the earphones provided in this embodiment when worn on the ear. A first channel 131 may also be formed within the first cavity 13, connecting the end face 121 and the hollow channel 21. It is understood that airflow between the hollow channel 21 and the end face 121 can be facilitated via the first channel 131.

[0168] For example, to facilitate the formation of the first channel 131, a first annular protrusion 122 can be formed on the outer side wall 12 of the housing 10, surrounding the end face 121 and protruding towards the hollow channel 21. The first annular protrusion 122 defines the first channel 131. The first annular protrusion 122 can be sealed to the hollow channel 21 using materials such as double-sided tape, glue, or sealing rings, so that airflow between the hollow channel 21 and the end face 121 can be conducted through the first channel 131.

[0169] It is understandable that the end face 121 and the hollow channel 21 are connected through the first cavity, which can be through the cavity region within the first cavity 13 (i.e., the structure shown in FIG15 of this disclosure), or through the channel formed by the structural members in the first cavity 13 (i.e., the first channel 131, the structure shown in FIG20 of this disclosure).

[0170] Understandably, the airflow between the hollow channel 21 and the end face 121 is achieved through the first channel 131. Therefore, the shorter the channel path between the end face 121 and the hollow channel 21, the better, that is, the shorter the length of the first channel 131, the better, so as to improve the transparency of the earphone 100.

[0171] It is also understandable that the length of the first channel 131 can be understood as the height of the first annular protrusion 122 in the direction toward the hollow channel 21. That is, the smaller the height of the first annular protrusion 122 in the direction toward the hollow channel 21, the better. For example, the height of the first annular protrusion 122 in the direction toward the hollow channel 21 can range from 0 mm to 10 mm, that is, the height of the first annular protrusion 122 is greater than or equal to 0 mm and less than or equal to 10 mm. For example, the height of the first annular protrusion 122 can be 0 mm, 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, etc. It is understood that when the height of the first annular protrusion 122 is 0 mm, the outer wall 12 with the end face 121 fits against the electroacoustic transducer 20.

[0172] The first channel 131 serves to guide airflow. Therefore, in order to effectively improve the transparency of the earphone 100, the minimum cross-sectional area of ​​the first channel 131 is greater than or equal to the maximum cross-sectional area of ​​the hollow channel 21, so as to improve the airflow conduction.

[0173] For example, the minimum cross-sectional area of ​​the first channel 131 is greater than or equal to 5 square millimeters, more preferably, the minimum cross-sectional area of ​​the first channel 131 is greater than or equal to 10 square millimeters, and even more preferably, the minimum cross-sectional area of ​​the first channel 131 is greater than or equal to 20 square millimeters.

[0174] It should be noted that, since the end face 121 and the hollow channel 21 are connected through the first channel 131 within the first cavity 13, the opening / closing component 30 can be located within the first channel 131 to open or close the connection of the first channel 131. For example, the opening / closing component 30 can be connected to the inner wall of the first channel 131. This reduces the difficulty of installing the opening / closing component 30 within the first cavity 13, and by using the opening / closing component 30 to control the connection or disconnection of the first channel 131, the connection or disconnection of the end face 121 and the hollow channel 21 can be achieved.

[0175] In some embodiments, in order to achieve the tuning function, a rear sound outlet can also be provided on the earphone 100. For example, referring to FIG20, the housing 10 has a first rear sound outlet 16, which is located on the side of the housing 10 away from the ear 200. The first rear sound outlet 16 communicates with the first cavity 13, so that the earphone 100 can be tuned through the first rear sound outlet 16.

[0176] In the above embodiment, the airflow between the hollow channel 21 and the end face 121 is achieved through the first channel 131 formed by the first annular protrusion 122 on the outer side wall 12. In other embodiments, other structures may also be used to achieve the airflow between the hollow channel 21 and the end face 121.

[0177] Alternatively, please refer to Figure 21, which is a fourth cross-sectional view of the earphones provided in this embodiment when worn on the ear. The earphones 100 may further include a middle shell 60, which covers the electroacoustic transducer 20. A second cavity 132 is defined between the middle shell 60 and the electroacoustic transducer 20. The second cavity 132 communicates with the hollow channel 21. The middle shell 60 is provided with a connecting hole 61, which connects the second cavity 132 and the end face hole 121. Thus, the airflow in the hollow channel 21 can flow through the second cavity 132 and the connecting hole 61 to the end face hole 121, thereby achieving airflow communication between the hollow channel 21 and the end face hole 121.

[0178] Understandably, the addition of the middle shell 60 allows for the installation of different sizes of the middle shell 60 as needed, thus improving the practicality and convenience of the headphone 100.

[0179] In some other embodiments, please refer to FIG22, which is a fifth cross-sectional view of the earphones provided in this embodiment of the present disclosure when worn on the ear. A middle shell 60 covers the electroacoustic transducer 20 to define a second cavity 132 and a second channel 134 that are not interconnected. The second channel 134 communicates with the hollow channel 21. The middle shell 60 is provided with a connecting hole 61 that communicates with the second channel 134 and the end face hole 121. Thus, airflow in the hollow channel 21 can flow through the second channel 134 and the connecting hole 61 to the end face hole 121, thereby achieving airflow communication between the hollow channel 21 and the end face hole 121.

[0180] The middle shell 60 includes a bottom wall 62 opposite to the electroacoustic transducer 20. A connecting hole 61 is disposed on the bottom wall 62. The bottom wall 62 has a second annular protrusion 621 surrounding the connecting hole 61 and protruding towards the hollow channel 21. The second annular protrusion 621 defines a second channel 134 communicating with the hollow channel 21. The second annular protrusion 621 can be sealed to the hollow channel 21 using materials such as double-sided tape, glue, or sealing rings, so that airflow between the hollow channel 21 and the end hole 121 can be conducted through the second channel 134.

[0181] Understandably, the airflow between the hollow channel 21 and the end face 121 is achieved through the second channel 134. Therefore, the shorter the channel path between the end face 121 and the hollow channel 21, the better, that is, the shorter the length of the second channel 134, the better, so as to improve the transparency of the earphone 100.

[0182] It is also understandable that the length of the second channel 134 can be interpreted as the height of the second annular protrusion 621 in the direction toward the hollow channel 21. That is, the smaller the height of the second annular protrusion 621 in the direction toward the hollow channel 21, the better. For example, the height of the second annular protrusion 621 in the direction toward the hollow channel 21 ranges from 0 mm to 10 mm, meaning the height is greater than or equal to 0 mm and less than or equal to 10 mm. For instance, the height of the second annular protrusion 621 can be 0 mm, 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, etc. It is understood that when the height of the second annular protrusion 621 is 0 mm, the bottom wall 62 of the middle shell with the connecting hole 61 fits against the electroacoustic transducer 20.

[0183] The second channel 134 serves to guide airflow. Therefore, in order to effectively improve the transparency of the earphone 100, the minimum cross-sectional area of ​​the second channel 134 is greater than or equal to the maximum cross-sectional area of ​​the hollow channel 21, so as to improve the airflow conduction.

[0184] For example, the minimum cross-sectional area of ​​the second channel 134 is greater than or equal to 5 square millimeters, more preferably, the minimum cross-sectional area of ​​the second channel 134 is greater than or equal to 10 square millimeters, and even more preferably, the minimum cross-sectional area of ​​the second channel 134 is greater than or equal to 20 square millimeters.

[0185] To enable tuning, a rear sound outlet can be provided on the earphone 100. For example, as shown in Figure 22, the housing 10 has a second rear sound outlet 17 located on the side of the housing 10 away from the ear 200. When the middle housing 60 covers the electroacoustic transducer 20, the middle housing 60 divides the first cavity 13 into a second cavity 132 and a third cavity 133. The second rear sound outlet 17 communicates with the third cavity 133. The middle housing 60 is provided with a first sound outlet communication hole 63, which connects the second cavity 132 and the third cavity 133. Thus, the second cavity 132, the first sound outlet communication hole 63, the third cavity 133, and the second rear sound outlet 17 can be connected, allowing the earphone 100 to tune through the second rear sound outlet 17.

[0186] Understandably, the bottom wall 62 of the middle shell is arranged opposite to the outer wall 12 of the shell 10. In order to minimize the distance between the bottom wall 62 of the middle shell and the outer wall 12, the bottom wall 62 of the middle shell can fit against the outer wall 12. In this way, the end face hole 121 can better communicate with the connecting hole 61 of the bottom wall 62 of the middle shell.

[0187] In some embodiments, the middle shell 60 and the shell 10 are provided separately. It should be noted that the middle shell 60 and the shell 10 can be integrally molded; for example, both can be plastic parts, integrally molded by injection molding or secondary injection molding. This can improve the connection stability of the middle shell 60 and the shell 10, thereby enhancing the structural stability of the earphone 100.

[0188] The middle shell 60 and the shell 10 can be separate structures that are interconnected. For example, they can be connected by a snap-fit ​​mechanism, i.e., the middle shell 60 can have a snap-fit ​​protrusion, and the shell 10 can have a snap-fit ​​hole, with the snap-fit ​​protrusion engaging in the snap-fit ​​hole to connect the middle shell 60 and the shell 10. Alternatively, the middle shell 60 and the shell 10 can also be connected by fasteners. This disclosure is not limited to the connection method of the middle shell 60 and the shell 10. This improves the connection flexibility of the middle shell 60 and the shell 10, facilitates structural design and assembly, and thus enhances the structural flexibility of the headphones.

[0189] In some embodiments, referring to FIG21, the bottom wall 62 of the middle shell 60 and the outer wall 12 of the shell 10 can be fitted together. In other embodiments, the middle shell 60 may not have a bottom wall 62, and the side wall of the middle shell 60 may be directly connected to the outer wall 12 of the shell 10. In this way, a second cavity 132 can also be formed, and the removal of the bottom wall 62 can help reduce the axial thickness of the earphone 100, thus helping the earphone 100 to be thinner and lighter.

[0190] In another embodiment, please refer to Figure 23, which is a sixth cross-sectional view of the earphones provided in this embodiment when worn on the ear. The middle shell 60 covers the electroacoustic transducer 20 to form a second cavity 132. To achieve the tuning function, a third rear sound outlet 18 can be provided on the outer wall 12 of the shell 10, and a second sound outlet communication hole 622 communicating with the second cavity 132 can be provided on the bottom wall 62 of the middle shell. The third rear sound outlet 18 communicates with the second sound outlet communication hole 622. Thus, the third rear sound outlet 18 communicates with the second cavity 132 through the second sound outlet communication hole 622, allowing the earphones 100 to tune through the third rear sound outlet 18.

[0191] Example 3

[0192] The present disclosure will now be described in detail with reference to embodiments.

[0193] Please refer to Figures 24 to 33. This disclosure provides an earphone, which can be either an over-ear or on-ear type. For ease of detailed description of the earphone's structure, the following embodiments use an over-ear earphone as an example.

[0194] Please refer to Figures 24 and 25. The headphones include a housing 100, which serves as the main body of the headphones and is used to carry the various components of the headphones. It also facilitates placing the headphones over the user's ears so that the entire ear is covered within the cavity formed by the headphones and the head.

[0195] The headphones also include an electroacoustic transducer 200, which can convert the electrical signal output from the sound source into sound that can be heard by the human ear. The electroacoustic transducer 200 is disposed inside the housing 100, that is, the housing 100 covers the electroacoustic transducer 200.

[0196] The electroacoustic transducer 200 is provided with a hollow channel 210 extending along its own axis; that is, the hollow channel extends along its own axis through two oppositely arranged walls of the electroacoustic transducer 200, so that the electroacoustic transducer 200 generally presents a ring structure. It should be noted that the shape of the hollow channel can be regular or irregular. For example, the cross-section perpendicular to the axis of the electroacoustic transducer 200 is the longitudinal section, and the longitudinal section shape of the hollow channel can be circular, square, or other regular shapes.

[0197] In this example, the electroacoustic transducer 200 includes a vibration system and a magnetic circuit system. The vibration system includes a diaphragm, a first voice coil, and a second voice coil. The diaphragm surrounds a hollow channel 210, meaning the hollow channel 210 penetrates the diaphragm. The first voice coil is connected to the diaphragm and surrounds the hollow channel, and the second voice coil is connected to the diaphragm and surrounds the outer periphery of the first voice coil. The magnetic circuit system drives the first and second voice coils to vibrate and produce sound. It should be noted that the structure of the magnetic circuit system is existing technology, and will not be described in detail here.

[0198] Please refer to Figure 25. The housing 100 has a first sound outlet 110, which is located on the side of the housing 100 facing the ear. The orthographic projection of the first sound outlet 110 onto the electroacoustic transducer 200 at least partially overlaps with the hollow channel 210, allowing communication between the first sound outlet 110 and the electroacoustic transducer 200. It is understood that when the headphones are worn, the diaphragm of the electroacoustic transducer 200 vibrates, radiating sound into the anterior cavity. This allows the emitted sound signal to pass through the first sound outlet 110 into the ear canal.

[0199] The housing 100 also has an end face 120, which is located on the side of the housing 100 away from the ear. For ease of detailed description of the positions of the first sound outlet 110 and the end face 120, the wall of the housing 100 near the ear can be referred to as the inner wall, and the wall of the housing 100 away from the ear and opposite to the inner wall can be referred to as the outer wall 160. The first sound outlet 110 is located on the inner wall of the housing 100, penetrates the inner wall, and communicates with the hollow channel 210 of the electroacoustic transducer 200. The end face 120 is located on the outer wall 160 of the housing 100 and penetrates the outer wall 160, thereby enabling the end face 120 to communicate with the external environment.

[0200] It is important to understand that in order to allow the gas in the cavity formed by the shell 100 and the ear to diffuse into the external environment, so as to dissipate the heat inside the earphone and keep the ear comfortable, the end face 120 needs to be connected to the hollow channel 210, thereby realizing the sequential connection of the first sound outlet 110, the hollow channel 210 and the end face 120.

[0201] The connection between the hollow channel 210 and the end face 120 can be understood as a direct or indirect connection. In one example, the connection between the hollow channel 210 and the end face 120 is a direct connection, meaning that at least the portion of the housing 100 with the end face 120 is fitted to the electroacoustic transducer 200, thus connecting the end face 120 to the hollow channel 210. It should be noted that the area of ​​the housing 100 opposite to the rear tuning port 220 of the electroacoustic transducer 200 has a certain gap to prevent blockage of the rear tuning port 220. In another example, the hollow channel 210 is indirectly connected to the end face 120. For instance, a connecting channel 130 is formed within the housing 100, which overlaps at least with both the hollow channel 210 and the end face 120, thereby connecting the hollow channel 210 and the end face 120. This allows the first sound outlet 110, the hollow channel 210, and the end face 120 to be sequentially connected in an axial direction parallel to the electroacoustic transducer 200. It is understood that airflow between the hollow channel 210 and the end face 120 is achieved through the connecting channel 130. Therefore, the shorter the path between the end face 120 and the hollow channel 210, the better; that is, the shorter the length of the connecting channel 130, the better, to improve the headphone's transparency.

[0202] It should be noted that, for ease of understanding, a plane perpendicular to the axial direction of the electroacoustic transducer 20 can be considered as the first reference plane, i.e., the plane shown in Figure 25 is the first reference plane. The connecting channel 130 at least coincides with the hollow channel 210. This can be understood as the dimension of the connecting channel 130 in the axial direction perpendicular to the electroacoustic transducer 200 being greater than or equal to the dimension of the hollow channel 210 in the axial direction perpendicular to the electroacoustic transducer 200. That is, the cross-sectional area of ​​the connecting channel 130 is greater than or equal to the cross-sectional area of ​​the hollow channel 210. This configuration can improve the airflow conduction effect of the connecting channel 130, thereby effectively improving the transparency of the headphones. Correspondingly, the connecting channel 130 at least coincides with the end face 120, as described above, and will not be repeated here.

[0203] In this embodiment, by setting the hollow channel 210, the end face 120, and the connecting channel 130, the first sound outlet 110 can be connected to the end face 120 through the hollow channel 210 and the connecting channel 130, thereby realizing the connection between the first sound outlet 110 and the external environment. This not only provides an open listening environment for the ears, allowing users to listen to music while also monitoring external sounds, thus meeting different listening needs of users, but also dissipates heat inside the headphones, keeping the ears in a comfortable state.

[0204] In addition, by setting a hollow channel 210 in the electroacoustic transducer 200, the path length of airflow or sound between the first sound outlet 110 and the end face 120 can be reduced to the minimum, effectively improving the transparency of the headphones.

[0205] Please refer to Figure 25. A first resonant cavity 300 is formed on the side of the earphone facing the ear 10. The first resonant cavity 300 is connected to the first sound outlet 110. When the earphone is worn, the first resonant cavity 300 covers the ear 10. It should be understood that the first resonant cavity 300 can be formed by the housing 100 itself, or it can be formed by other components enclosing the housing 100. For example, the housing 100 has an ear pad 700 on the side facing the ear 10, that is, the ear pad 700 is disposed on the inner wall of the housing 100; the ear pad 700 and the inner wall of the housing 100 enclose the first resonant cavity 300, which is connected to the inner cavity of the housing 100 through the first sound outlet 110. When the earphone is worn, the ear pad 700 fits against the head, thereby covering the ear 10. The ear pad 700 can be made of a flexible material, thereby improving wearing comfort.

[0206] Given that the ear pad 700 is placed on the ear 10, the first resonant cavity 300 forms a relatively closed chamber, and the first resonant cavity 300 is connected in sequence through the first sound outlet 110, the hollow channel 210, the connecting channel 130 and the end face 120, so that the above-mentioned components form a cavity structure with one end closed and the other end open, thereby making the first resonant cavity 300, the first sound outlet 110, the hollow channel 210, the connecting channel 130 and the end face 120 form a first Helmholtz resonance system.

[0207] Please refer to Figure 25. A second resonant cavity 140 is also formed inside the housing 100. The side of the housing 100 away from the ear has a second sound outlet 150, which is spaced apart from the end face 120. In other words, the second sound outlet 150 is disposed on the outer side wall of the housing 100 and is distributed on the opposite side wall of the housing 100 to the first sound outlet 110.

[0208] The second resonant cavity 140 connects to the rear tuning port 220 and the second sound outlet 150 of the electroacoustic transducer 200. Understandably, the rear tuning port 220 is located on the electroacoustic transducer 200, with one end connected to the magnetic gap of the magnetic circuit system of the electroacoustic transducer 200, and the other end connected to the second resonant cavity 140. The second resonant cavity 140 can be approximately a ring structure, surrounding the electroacoustic transducer 200. This arrangement reduces the difficulty of selecting the location of the rear tuning port 220 and facilitates the communication between the rear tuning port 220 and the second resonant cavity 140.

[0209] The rear tuning port 220 of the electroacoustic transducer 200 is connected to the second sound outlet 150 through the second resonant cavity 140, so that the above-mentioned components form a cavity structure with one end closed and the other end open, thereby making the second resonant cavity 140 and the second sound outlet 150 form a second Helmholtz resonance system. In addition, the rear tuning port 220 and the second sound outlet 150 are connected and cooperate with each other to achieve the function of tuning.

[0210] When the diaphragm of the electroacoustic transducer 200 vibrates, the diaphragm can also radiate sound into the second resonant cavity 140, so that the sound is radiated outward through the tuning hole 220, the second resonant cavity 140, and the second sound outlet 150 in sequence. According to the sound generation principle of the electroacoustic transducer 200, the sound emitted from the front and rear of the diaphragm is out of phase; however, in this embodiment, the sound emitted from the front of the diaphragm of the electroacoustic transducer 200 can be radiated out through the end face 120 of the first Helmholtz resonant system, and the sound emitted from the rear of the diaphragm of the electroacoustic transducer 200 can be radiated out through the second sound outlet 150 of the second Helmholtz resonant system. By adjusting the parameters of the first resonant cavity, the second resonant cavity, the first sound outlet, the end face 120, the second sound outlet, and the channels between the first resonant cavity and the end face 120, and the channels between the second resonant cavity and the sound outlet, the sound signals emitted from the end face 120 and the second sound outlet 150 are out of phase.

[0211] Based on the above theory, the end face 120 and the second sound outlet 150 constitute a dipole sound source within a preset frequency range. By setting up the dipole sound source, the sound in the far sound field can be reduced, thus preventing sound leakage from the headphones, improving the privacy of the headphones, and protecting user privacy. Therefore, the headphones provided in this embodiment of the present disclosure can address both the breathability issue and the sound leakage problem.

[0212] It should be understood that since the end face 120 is connected to the first resonant cavity 300 through the connecting channel 130, the sound emitted from the end face 120 is said to be the sound emitted from the front of the diaphragm of the electroacoustic transducer 200. At the same time, the second sound outlet 150 is connected to the second resonant cavity 140 located behind the diaphragm of the electroacoustic transducer 200; therefore, the sound emitted from the second sound outlet 150 is said to be the sound emitted from the rear of the diaphragm of the electroacoustic transducer 200.

[0213] In this embodiment, the shapes of the first sound hole 110, the end face hole 120, and the second sound hole 150 can be circular, but are not limited to circular. They can also include one or more of the following: elliptical, racetrack-shaped, triangular, rectangular, polygonal, or other complex shapes with decorative features. This disclosure does not impose any limitations on these shapes.

[0214] Please continue referring to Figure 25. The end face 120 and the second sound outlet 150 are spaced apart. For example, the minimum radial distance between the end face 120 and the second sound outlet 150 of the electroacoustic transducer 200 is between 7 mm and 28 mm. That is, the distance between the end face 120 and the second sound outlet 150 refers to the dimension in the vertical direction in Figure 25. Specifically, the minimum radial distance between the end face 120 and the second sound outlet 150 of the electroacoustic transducer 200 is 8 mm, 10 mm, 15 mm, 20 mm, or 28 mm.

[0215] If the minimum radial distance between the end face 120 and the second sound outlet 150 in the electroacoustic transducer 200 is less than 7 mm, the distance between the end face 120 and the second sound outlet 150 will be too small. The sound emitted from the second sound outlet 150 will affect the sound emitted from the first sound outlet 110, especially the low frequencies, resulting in fewer low frequencies being heard by the human ear and affecting the sound quality. If the minimum radial distance between the end face 120 and the second sound outlet 150 in the electroacoustic transducer 200 is greater than 28 mm, the distance between the end face 120 and the second sound outlet 150 will be too large, resulting in an excessively large size of the housing 100. This means that the distance between the two similar dipole sound sources will increase, thereby affecting the cancellation of far-field sound and reducing the sound leakage prevention effect.

[0216] Therefore, in this embodiment, the minimum radial distance between the end face 120 and the second sound outlet 150 in the electroacoustic transducer 200 is between 7 mm and 28 mm. This ensures that the sound emitted by the end face 120 and the second sound outlet 150 is well canceled in the far sound field, reducing sound leakage from the headphones. It also avoids increasing the size of the housing, making it easy to carry.

[0217] It should be understood that the housing 100 can be a split structure. For example, referring to FIG24, the housing 100 may include a base 170 and an outer shell 180, the outer shell 180 covering the base 170 and being detachably connected to the base 170 so that a mounting cavity is formed inside the housing 100.

[0218] Referring to Figures 24 and 25, the end face 120 is disposed on the wall surface of the outer casing 180 facing away from the base 170, the first sound outlet 110 is disposed on the wall surface of the base 170 facing away from the outer casing 180, and the electroacoustic transducer 200 is disposed on the base 170 and opposite to the first sound outlet 110. In this embodiment, a third annular protrusion 171 is formed on the wall surface of the base 170 facing the outer casing 180, and the third annular protrusion 171 surrounds the first sound outlet 110; the electroacoustic transducer 200 is disposed in the area enclosed by the third annular protrusion 171 and is fixedly connected to the third annular protrusion 171 to improve the stability of the electroacoustic transducer 200. It should be noted that when the casing 100 includes the base 170 and the outer casing 180, the ear pad 700 is disposed on the base 170, and the ear pad 700, the base 170, the electroacoustic transducer 200, and the head form a first resonant cavity 300.

[0219] In order to maximize the first Helmholtz resonant frequency f1 and the openness of the headphones, the area of ​​the first sound outlet 110 is larger than the area of ​​the electroacoustic transducer 200 in the diaphragm plane direction. This results in a larger area of ​​the first sound outlet 110, which in turn makes it possible for the diaphragm of the electroacoustic transducer 200 to be touched by the user.

[0220] In view of this, one or more of the following methods are typically used to protect the diaphragm at the first sound outlet 110: metal mesh, foam, mesh fabric, or plastic bracket. In one example, the metal mesh, foam, mesh fabric, or plastic bracket is fixedly connected to the base 170 through processes such as adhesive bonding, heat fusion, or ultrasonic bonding. In another example, the metal mesh or mesh fabric is fixedly connected to the base 170 through injection molding. In yet another example, referring to Figures 32 and 33, a plastic bracket 800 can be formed on the inner wall of the first sound outlet 110, extending away from the electric transducer 200; or, the plastic bracket 800 can be formed on the base, extending away from the electric transducer 200 and surrounding the first sound outlet 110. The plastic bracket 800 has a through hole 810 opposite to the first sound outlet 110. The through hole 810 and the first sound outlet 110 are interconnected, and the diameter of the through hole 810 is smaller than the diameter of the first sound outlet 110. This design protects the diaphragm while ensuring the sound output effect of the headphones. When the plastic bracket 800 is placed on the base, it can be injection molded together with the base to form a complete component, simplifying the headphone manufacturing process.

[0221] In addition, the first sound outlet 110 can be divided into multiple parts, that is, multiple holes are provided on the housing 100, and the multiple holes constitute the first sound outlet 110. With this arrangement, the size of each hole is smaller than the first sound outlet 110, which can prevent it from being scratched by external devices.

[0222] In one possible implementation, in order to enable the end face 120 and the second sound outlet 150 to form a dipole sound source within a preset frequency range, this embodiment further sets various parameters of the first Helmholtz resonance system and the second Helmholtz resonance system. The first Helmholtz resonance system has a first Helmholtz resonance frequency f1, which conforms to the following formula (1):

[0223] Where c0 is the speed of sound in the air;

[0224] S1 is the cross-sectional area of ​​the second channel; wherein, the hollow channel, the connecting channel, and the end face together define the second channel;

[0225] V1 is the volume of the first resonant cavity;

[0226] L1 is the axial length of the second channel;

[0227] r1 is the equivalent radius of the cross-sectional area of ​​the second channel.

[0228] It should be noted that the selection of the cross-sectional area of ​​the second channel 500 needs to be based on the values ​​of the cross-sectional areas of the hollow channel 210, the connecting channel 130, and the end face 120. For example, if the cross-sectional areas of the hollow channel 210, the connecting channel 130, and the end face 120 are approximately equal, the cross-sectional area of ​​the second channel 500 can be the average of the cross-sectional areas of the hollow channel 210, the connecting channel 130, and the end face 120; or, for example, if the difference between any two of the cross-sectional areas of the hollow channel 210, the connecting channel 130, and the end face 120 is large, the smaller cross-sectional area can be selected as the cross-sectional area of ​​the second channel 500; it should be understood that, given that it can be clearly seen from formula (1) that the cross-sectional area S1 and the first Helmholtz cross-sectional area are equal, the cross-sectional area of ​​the second channel 500 is determined by the average values ​​of the cross-sectional areas of the hollow channel 210, the connecting channel 130, and the end face 120. The resonant frequency f1 is directly proportional, but in this example, a smaller cross-sectional area is chosen as the cross-sectional area of ​​the second channel 500. The reason is that in actual products, the second channel 500 varies depending on the product model. If the smallest cross-sectional area is used for simulation, the results show that the first Helmholtz resonant frequency f1 can satisfy the condition of being as large as possible and approximately equal to the second Helmholtz resonant frequency f2. Therefore, the cross-sectional area of ​​the second channel 500 can be adjusted according to the simulation results. For example, when the length of the connecting channel 130 is large, the cross-section of the hollow channel 210 is selected as the cross-sectional area of ​​the second channel 500.

[0229] At the same time, the second Helmholtz resonance system has a second Helmholtz resonance frequency f2, which conforms to the following formula (2):

[0230] Where c0 is the speed of sound in the air;

[0231] S2 is the opening area of ​​the second sound hole;

[0232] V2 is the volume of the second resonant cavity;

[0233] L2 is the axial length of the second sound hole.

[0234] r2 is the equivalent radius of the cross-sectional area of ​​the second sound hole.

[0235] From formulas (1) and (2), it can be concluded that the first Helmholtz resonance frequency f1 is related to the cross-sectional area and length of the second channel and the volume of the first resonant cavity; the second Helmholtz resonance frequency f2 is related to the opening area and length of the second sound hole and the volume of the second resonant cavity.

[0236] To ensure that the sound signals radiated by the end face 120 and the second sound outlet 150 meet the conditions of a dipole sound source over a wide frequency range, the first Helmholtz resonant frequency f1 and the second Helmholtz resonant frequency f2 need to be as close to high frequencies as possible. For example, the first Helmholtz resonant frequency f1 ≥ 5000Hz and the second Helmholtz resonant frequency f2 ≥ 5000Hz. For instance, the first Helmholtz resonant frequency f1 and the second Helmholtz resonant frequency f2 are approximately 6000Hz, so that the frequency response curve of the end face 120 and the frequency response curve of the second sound outlet 150 at these resonant frequencies are approximately the same. This results in the two frequency response curves having similar amplitudes and opposite phases, thus ensuring that the sound emitted by the end face 120 and the second sound outlet 150 approximately meets the conditions of a dipole sound source. This further reduces the sound in the far sound field, preventing sound leakage from the headphones and protecting user privacy.

[0237] To bring the first Helmholtz resonant frequency f1 as close to the high frequency as possible, the embodiments of this disclosure reasonably set the cross-sectional area and length of the second channel 500 and the volume of the first resonant cavity. In one example, referring to FIG25, the hollow channel 210, the connecting channel 130, and the end face 120 together define the second channel 500, the length of which is less than or equal to 43 mm. For example, the length of the second channel 500 is 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 40 mm, or 43 mm. It is understood that the length of the second channel 500 refers to the dimension of the second channel 500 along the axial direction of the electroacoustic transducer 200.

[0238] To ensure that the sound signals radiated by the end face 120 and the second sound outlet 150 meet the requirements of a dipole sound source over a wide frequency range, the resonant frequencies f1 and f2 of the first and second Helmholtz resonant systems should be as large as possible, so that f1 and f2 are as close to high frequencies as possible. Therefore, the length of the second channel 500 needs to be designed to be as short as possible. In addition, a shorter second channel 500 can also improve the conductivity between the first resonant cavity 300 and the external environment, thereby improving the user's ear comfort.

[0239] The volume of the first resonant cavity 300 is less than or equal to 55 cubic centimeters (cm3). For example, the volume of the first resonant cavity 300 is 55 cubic centimeters (cm3), 53 cubic centimeters (cm3), 50 cubic centimeters (cm3) or 45 cubic centimeters (cm3). According to formula (1), the resonant frequency f1 of the first Helmholtz resonant system is inversely proportional to the volume of the first resonant cavity 300. Therefore, the smaller the volume of the first resonant cavity 300, the closer the resonant frequency f1 of the first Helmholtz resonant system is to the high frequency.

[0240] The minimum cross-section of the hollow channel 210 of the electroacoustic transducer 200 needs to be sufficiently large, wherein the minimum cross-sectional area of ​​the hollow channel 210 is not less than 5 square millimeters (mm2), more preferably, the minimum cross-sectional area of ​​the hollow channel 210 is not less than 10 square millimeters (mm2), and even more preferably, the minimum cross-sectional area of ​​the hollow channel 210 is not less than 20 square millimeters (mm2).

[0241] The minimum cross-sectional area of ​​the connecting channel 130 is not less than 5 square millimeters (mm2), more preferably, the minimum cross-sectional area of ​​the connecting channel 130 is not less than 10 square millimeters (mm2), and even more preferably, the minimum cross-sectional area of ​​the connecting channel 130 is not less than 20 square millimeters (mm2).

[0242] The minimum area of ​​the end face 120 is not less than 15 square millimeters (mm2), more preferably, the minimum area of ​​the end face 120 is not less than 25 square millimeters (mm2), and even more preferably, the minimum area of ​​the end face 120 is not less than 40 square millimeters (mm2).

[0243] In this embodiment, the cross-sectional areas of the hollow channel 210, the connecting channel 130, and the end face 120 of the electroacoustic transducer 200 provided above can be reasonably selected and adjusted so that the first Helmholtz resonance frequency f1 is as close as possible to the high frequency.

[0244] Meanwhile, in order to make the second Helmholtz resonant frequency f2 as close as possible to the high frequency, the embodiments of this disclosure reasonably limit the volume of the second resonant cavity 140, the opening area of ​​the second sound outlet 150, and the length of the second sound outlet 150.

[0245] For example, the volume of the second resonant cavity 140 is between 6 cubic centimeters (cm3) and 55 cubic centimeters (cm3). For instance, the volume of the second resonant cavity 140 can be 6 cubic centimeters (cm3), 10 cubic centimeters (cm3), 15 cubic centimeters (cm3), 20 cubic centimeters (cm3), 25 cubic centimeters (cm3), 30 cubic centimeters (cm3), 35 cubic centimeters (cm3), 40 cubic centimeters (cm3), 45 cubic centimeters (cm3), 50 cubic centimeters (cm3), or 55 cubic centimeters (cm3). Preferably, the volume of the second resonant cavity 140 is 40 cubic centimeters (cm3). This configuration ensures that the second Helmholtz resonant frequency f2 is as close to the high frequencies as possible, and makes it easier to adjust to be approximately the same as the first Helmholtz resonant frequency f1. This results in lower sound levels in the far sound field, preventing sound leakage from the headphones and protecting user privacy. This also avoids making the volume of the second resonant cavity 140 too large, ensuring the compactness of the headphones.

[0246] The opening area of ​​the second sound outlet 150 is greater than or equal to 15 square millimeters (mm2). Along the axial direction of the electroacoustic transducer 200, the length of the second sound outlet is between 1 millimeter (mm) and 55 millimeters (mm). The opening area of ​​the second sound outlet 150 is directly proportional to the second Helmholtz resonant frequency f2, and the length of the second sound outlet 150 is inversely proportional to the second Helmholtz resonant frequency f2. A larger opening area and a smaller length of the second sound outlet 150 ensure that the second Helmholtz resonant frequency f2 is as close to the high frequencies as possible, making it easier to adjust it to be approximately the same as the first Helmholtz resonant frequency f1. This results in the generation of anti-phase sound field superposition at the far field of the headphones, reducing sound loudness and clarity, thus preventing others at a distance from the headphones from clearly hearing the sound emitted by the headphones, preventing sound leakage and protecting user privacy.

[0247] According to the above parameter settings, this embodiment can make the first Helmholtz resonance frequency f1 and the second Helmholtz resonance frequency f2 approximately equal, where |f1-f2|≤300Hz. For example, the first Helmholtz resonance frequency f1 and the second Helmholtz resonance frequency f2 are approximately 1000Hz.

[0248] To better explain why it is necessary to adjust the parameters of the first and second Helmholtz resonance systems in this embodiment, a detailed explanation will be provided below in conjunction with the two frequency response curves.

[0249] Figure 26 shows the frequency response curves of the sound emitted by end face 120 and the sound emitted by the second sound outlet 150 before parameter adjustment. From Figure 26, it is clear that the first Helmholtz resonant frequency f1 is approximately 1000Hz, while the second Helmholtz resonant frequency f2 is approximately 2200Hz. It can be seen that within the frequency response bandwidths centered on f1 and f2, such as the frequency response of the bandwidth 600Hz-1600Hz (a0-a1) centered on f1 and the frequency response of the bandwidth 1000Hz-4000Hz (b0-b1) centered on f2, the amplitudes differ significantly. Therefore, the frequency response curves of end face 120 and the second sound outlet 150 cannot meet the condition of approximately the same amplitude and opposite phase in some frequency bands, resulting in end face 120 and the second sound outlet 150 failing to form a dipole sound source within the preset frequency range.

[0250] Figure 27 shows the frequency response curves of the sound emitted from end face 120 and the sound emitted from the second sound outlet 150 after parameter adjustment. After adjustment, the second Helmholtz resonant frequency f2 in the frequency response curve emitted from the second sound outlet is close to 1000Hz, thus making the frequency response amplitude of the 600Hz-1600Hz (b0'-b1') frequency response bandwidth centered on f2 close to the amplitude of the 600Hz-1600Hz (a0-a1) frequency response bandwidth centered on f1, thereby forming a dipole sound source. Considering that the frequency response amplitudes of the frequency response bandwidths centered on frequencies f1 and f2 are closer, the difference between f1 and f2 is limited to be small, i.e., |f1-f2|≤300Hz.

[0251] Therefore, after adjusting the parameters of the first and second Helmholtz resonance systems, the first and second Helmholtz resonance frequencies f1 and f2 can be made approximately the same; thus, the end face 120 and the second sound outlet 150 form a dipole sound source in the frequency range of 200-10000Hz, thereby reducing the sound generated in the far field of the headphones and improving the headphones' ability to prevent sound leakage.

[0252] As one possible implementation of the connecting channel 130, please continue referring to Figure 25. The housing 100 also includes an outer wall 160, which is disposed opposite to the electroacoustic transducer 200. It should be noted that the specific shape of the outer wall 160 opposite to the electroacoustic transducer 200 depends on the shape of the electroacoustic transducer 200. For example, if the electroacoustic transducer 200 is cylindrical, the outer wall 160 can be a wall opposite to the bottom and top surfaces of the electroacoustic transducer 200, or it can be a wall opposite to the outer peripheral surface of the electroacoustic transducer 200. For the sake of detailed description of the outer wall 160, the following embodiments will all be described using the example of the outer wall 160 being a wall opposite to the bottom and top surfaces of the electroacoustic transducer 200.

[0253] An end face 120 is disposed on the outer side wall 160 and extends through the outer side wall 160 along its thickness direction. The outer side wall 160 has a first annular protrusion 161 that surrounds the end face 120 and protrudes toward the hollow channel 210. The first annular protrusion 161 defines a connecting channel 130. That is, the end of the first annular protrusion 161 facing away from the outer side wall 160 is connected to the electroacoustic transducer 200 such that the area enclosed by the inner wall of the first annular protrusion 161 is the connecting channel 130, and the first annular protrusion 161, the electroacoustic transducer 200, and the remaining area of ​​the outer side wall 160 enclose the second resonant cavity 140. It should be noted that the first annular protrusion 161, facing away from the outer wall, can be sealed to the electroacoustic transducer 200 by materials such as double-sided tape, glue, or sealing ring, so that the connecting channel 130 is at least partially opposite to the hollow channel 210 of the electroacoustic transducer 200, so that the end face 120 is connected to the hollow channel 210 through the connecting channel 130, thereby realizing the air communication between the hollow channel 210 and the external environment.

[0254] In this embodiment, the first annular protrusion 161 and the outer wall 160 can be integrally formed or separate structures. When the first annular protrusion 161 and the outer wall 160 are integrally formed, not only can the connection strength between the outer wall 160 and the first annular protrusion 161 be improved, thereby increasing the structural strength of the housing 100, but the manufacturing process of the housing 100 can also be simplified. When the first annular protrusion 161 and the outer wall 160 are separate structures, the position of the first annular protrusion 161 can be set according to requirements, and the spatial size of the connecting channel 130 and the second resonant cavity 140 can be reasonably adjusted.

[0255] In this embodiment, the connecting channel 130 is defined by the first annular protrusion 161 on the outer side wall 160, which can more accurately define the location and size of the connecting channel, thereby realizing the airflow between the end face 120 and the hollow channel 210, dissipating the heat inside the earphone, and keeping the ear comfortable.

[0256] It is important to understand that, in order to maximize the resonant frequency f1 of the first Helmholtz resonant frequency, the second channel 500 should be as short as possible. For example, the height of the first annular protrusion is 0 millimeters (mm), that is, at least the area of ​​the outer sidewall 160 of the housing 100 opposite to the electroacoustic transducer 200 is fitted to the electroacoustic transducer 200. However, it is important to understand that this part of the sidewall should not block the rear tuning hole 220 of the electroacoustic transducer 200.

[0257] As another possible implementation of the communication channel 130, please refer to FIG28. The housing 100 also includes an outer side wall 160 disposed opposite to the electroacoustic transducer 200, and an end face 120 disposed on the outer side wall 160.

[0258] The headphones also include a middle shell 400, which covers the electroacoustic transducer 200 to define a non-communicating middle shell channel 410 and a second resonant cavity 140. This can be understood as the middle shell 400 being located between the electroacoustic transducer 200 and the outer side wall 160, and covering the electroacoustic transducer 200. As a possible example of the middle shell 400, referring to Figure 28, the middle shell 400 can be a cylindrical body with an opening at one end, thus allowing the electroacoustic transducer 200 to be disposed within the inner cavity of the middle shell 400. Exemplarily, the middle shell 400 includes a bottom wall 430 and an annular side wall 440, wherein the side wall 440 is disposed on the side of the bottom wall 430 facing the electroacoustic transducer 200, and together with the bottom wall 430, forms the middle shell channel 410. The end of the middle shell sidewall 440 that faces away from the bottom wall 430 can be connected to the inner wall of the housing 100 or to the electroacoustic transducer 200. For example, the end of the middle shell sidewall 440 that faces away from the bottom wall 430 can be connected to the inner wall of the housing 100, thus ensuring that the middle shell channel 410 completely covers the electroacoustic transducer 200, increasing the area of ​​the middle shell channel 410.

[0259] To achieve communication between the middle shell channel 410 and the end face hole 120, the middle shell 400 is provided with a communication hole 420 communicating with the middle shell channel 410. For example, the middle shell bottom wall 430 is provided with a communication hole 420, and the communication hole 420 penetrates the middle shell bottom wall 430 along the thickness direction of the middle shell bottom wall 430, so that one end of the communication hole 420 communicates with the middle shell channel 410, and the other end of the communication hole 420 communicates with the end face hole 120.

[0260] The middle shell channel 410 and the connecting hole 420 define the connecting channel 130. In this example, by additionally setting a middle shell 400 and using the middle shell channel 410 and the connecting hole 420 of the middle shell 400 to define the connecting channel 130, the shape of the middle shell 400 can be adjusted according to actual needs, thereby adjusting the area of ​​the connecting channel 130, which is equivalent to reasonably adjusting the area of ​​the second channel in the first Helmholtz resonant system. When the sound emitted from the front of the diaphragm of the electroacoustic transducer 200 is radiated through the end face 120 of the first Helmholtz resonant system, the standing wave frequency and resonant frequency generated by the end face 120 can be optimized, thereby optimizing the frequency response curve of the sound signal generated by the headphones, making the sound in the far field smaller, thus preventing the sound from leaking out of the headphones, improving the privacy of the headphones, and protecting the user's privacy.

[0261] It should be noted that the middle shell channel 410 can be the entire inner cavity of the middle shell 400 or only a part of it. For example, referring to Figures 28, 29, and 30, the middle shell 400 includes a bottom wall 430 disposed opposite to the electroacoustic transducer 200. It is understood that the bottom wall 430 is disposed opposite to the outer wall 160, wherein the bottom wall 430 and the outer wall 160 can be fitted together or spaced apart. For example, the bottom wall 430 and the outer wall 160 are fitted together, so that there are no gaps between them. With this configuration, when heat inside the shell 100 is transferred to the connecting hole 420, it can be quickly diffused to the external environment through the end face 120, thereby shortening the transmission path length between the hollow channel 210 and the end face 120, preventing heat accumulation inside the earphone, improving the lifespan of various parts of the earphone, and enhancing the comfort of the user's ears.

[0262] In addition, the bottom wall 430 of the middle shell is attached to the outer wall 160, and the outer wall 160 can also provide support for the bottom wall 430 of the middle shell, which can increase the contact area between the bottom wall 430 of the middle shell and the outer wall 160, thereby improving the connection strength between the middle shell 400 and the shell 100.

[0263] The bottom wall 430 of the middle shell has a second annular protrusion 450 that surrounds the connecting hole 420 and protrudes towards the hollow channel 210. The second annular protrusion 450 defines the middle shell channel 410. That is, the second annular protrusion 450 is equivalent to a partition, dividing the area enclosed by the bottom wall 430 and the side wall 440 of the middle shell into two parts. The part opposite to the hollow channel 210 is the middle shell channel 410. This arrangement can shorten the dimension of the middle shell channel 410 in the direction perpendicular to the axis of the electroacoustic transducer 200, that is, in the vertical direction in Figure 29. This shortens the transmission path length between the hollow channel 210 and the end face 120, allowing the heat inside the shell 100 to be quickly diffused to the external environment through the end face 120. On the one hand, this can prevent heat from accumulating inside the earphone and improve the service life of various parts of the earphone; on the other hand, it can quickly dissipate the heat inside the earphone and keep the ears comfortable.

[0264] Please refer to Figures 29 and 30. The end of the second annular protrusion 450 facing the electroacoustic transducer 200 is connected to the electroacoustic transducer 200. For example, the end of the second annular protrusion 450 facing the electroacoustic transducer 200 can be sealed to the electroacoustic transducer 200 using materials such as double-sided tape, glue, or sealing rings. The connection position between the second annular protrusion 450 and the electroacoustic transducer 200 can be close to the hollow channel 210 of the electroacoustic transducer 200, or it can be at a predetermined distance from the hollow channel 210 of the electroacoustic transducer 200, so as to reasonably adjust the size of the shell channel 410 in the direction perpendicular to the axis of the electroacoustic transducer 200, thereby changing the area of ​​the shell channel 410. To maximize the resonant frequency f2 of the second Helmholtz resonant frequency, the height of the second annular protrusion 450 should be sufficiently low, for example, 0 mm.

[0265] Please refer to Figures 28 and 29. When the middle shell 400 is provided inside the housing 100, a relatively closed space is formed between the middle shell 400, the electroacoustic transducer 200 and the housing. In order to realize the connection between the rear tuning hole 220 of the electroacoustic transducer 200 and the second sound outlet 150, a sound outlet connection hole 460 is usually provided on the middle shell 400. The connection between the rear tuning hole 220 and the second sound outlet 150 is realized through the sound outlet connection hole 460.

[0266] As for the location of the sound outlet connection hole 460, it can be reasonably designed based on the location of the second resonant cavity 140 and the second sound outlet hole 150.

[0267] In one example, referring to Figure 30, the second resonant cavity 140 is formed by a portion of the inner cavity of the middle shell 400. For example, the second resonant cavity 140 is formed by the second annular protrusion 450 enclosing the middle shell 400's sidewall 440 and bottom wall 430, and the second sound outlet 150 is disposed on the outer sidewall 160 of the housing 100 in the region opposite to the second resonant cavity 140. Correspondingly, the bottom wall 430 of the middle shell is provided with a sound outlet communication hole 460 communicating with the second resonant cavity 140, and the sound outlet communication hole 460 is connected to the second sound outlet 150. This can be understood as follows: one end of the sound output connection hole 460 is connected to the rear tuning hole 220 through the second resonant cavity 140, and the other end of the sound output connection hole 460 is connected to the second sound output hole 150, so as to ensure that the rear tuning hole 220 of the electroacoustic transducer 200 is connected to the second sound output hole 150 through the second resonant cavity 140 and the sound output connection hole 460, so that the above-mentioned components form a cavity structure with one end closed and the other end open, thereby making the second resonant cavity 140 and the second sound output hole 150 form a second Helmholtz resonance system.

[0268] This embodiment can shorten the length of the transmission channel in the second Helmholtz resonant system. When the sound emitted from behind the diaphragm of the electroacoustic transducer 200 is radiated through the second sound outlet 150 of the second Helmholtz resonant system, the standing wave frequency and resonant frequency generated by the second sound outlet 150 can be optimized, thereby optimizing the frequency response curve of the sound signal generated by the headphones. This results in a smaller sound in the far sound field, preventing the sound from leaking out of the headphones, improving the privacy of the headphones, and protecting user privacy.

[0269] In another example, referring to Figures 28 and 29, the second resonant cavity 140 may be formed by a portion of the inner cavity of the middle shell 400 and a portion of the inner cavity of the housing 100. Exemplarily, a portion of the outer wall of the housing 100 is disposed opposite to the electroacoustic transducer 200 in its axial direction. Alternatively, the outer wall of the housing 100 includes a first portion disposed opposite to the electroacoustic transducer 200 in its axial direction and a second portion connected to the first portion, the second portion being obliquely disposed to the first portion, and the included angle between the second portion and the first portion being an obtuse angle.

[0270] At this time, when the second sound outlet 150 is disposed on the second part, the corresponding sound outlet communication hole 460 is opened on the middle shell sidewall 440 so that the sound outlet communication hole 460 connects the two parts of the second resonant cavity 140.

[0271] When the second sound outlet 150 is disposed on the first part, a corresponding sound outlet connecting hole 460 is disposed on the bottom wall 430 of the middle shell. The sound outlet connecting hole 460 and the second sound outlet 150 are disposed opposite to each other and at least partially overlap. In this embodiment, the sound outlet connecting hole 460 and the second sound outlet 150 share the same central axis, thereby minimizing the channel size from the middle shell channel 410 to the external environment.

[0272] In this embodiment, the cross-sectional area of ​​the region enclosed by the second annular protrusion 450 is greater than or equal to the cross-sectional area of ​​the hollow channel 210. By increasing the cross-sectional area of ​​the region enclosed by the second annular protrusion 450, the cross-sectional area of ​​the second channel 500 is increased, thereby maximizing the first Helmholtz resonance frequency f1.

[0273] The smaller the distance between the center point of the end face 120 and the central axis of the hollow channel 210 of the electroacoustic transducer 200, the better, so as to reduce the length of the second channel 500. Preferably, the distance between the center point of the end face 120 and the central axis of the hollow channel 210 of the electroacoustic transducer 200 is 0mm-36mm. More preferably, the distance is 0-20mm. Even more preferably, the distance is 0-5mm, so that the end face 120 and the hollow channel 210 are closer.

[0274] In one possible implementation, referring to Figure 31, the headphones also include an opening / closing component 600, which is disposed in the electroacoustic transducer 200 and used to open or close the hollow channel 210. It is understood that the opening / closing component 600 is used to open or close the hollow channel 210. It is also understood that when the opening / closing component 600 is in the closed state, there is no communication between the first sound outlet 110 and the end face 120. When the opening / closing component 600 is in the open state, the first sound outlet 110 can communicate with the end face 120 through the hollow channel 210, thereby enabling communication between the first sound outlet 110 and the external environment.

[0275] It should be noted that the opening / closing component 600 can be disposed not only on the electroacoustic transducer 200, but also in other locations. For example, the opening / closing component 600 can also be disposed on the housing 100. For instance, the opening / closing component 600 can be disposed on one side of the first sound outlet 110, used to open or close the first sound outlet 110. In this way, the opening or closing of the first sound outlet 110 can open or close the communication between the first sound outlet 110 and the external environment. Alternatively, the opening / closing component 600 can also be disposed on one side of the end face 120, used to open or close the end face 120, thus opening or closing the communication between the first sound outlet 110 and the external environment.

[0276] To enable the opening and closing function of the opening and closing component 600, a linkage mechanism (not shown) is also provided on the housing 100. One end of the linkage mechanism is located on the outside of the housing 100, and the other end of the linkage mechanism is connected to the opening and closing component 600, such as to the blade of the opening and closing component 600. The user drives the linkage mechanism to open or close the opening and closing component 600, thereby switching between the open and sealed states of the headphones.

[0277] In other embodiments, the linkage mechanism can be connected to a motor, which drives the linkage mechanism to open or close the opening and closing component 600. For example, the motor can receive instructions from the headphone main control chip to control the opening and closing of the opening and closing component 600.

[0278] The various embodiments or implementation methods described in this specification are presented in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referred to each other.

[0279] It should be noted that the terms "one embodiment," "embodiment," "exemplary embodiment," "some embodiments," etc., mentioned in the specification indicate that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Moreover, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments, whether explicitly described or not, is within the knowledge scope of those skilled in the art.

[0280] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit them. Although this disclosure 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 disclosure.

Claims

1. An electro-acoustic transducer, characterized by The electro-acoustic transducer has a hollow channel through along its own axial direction, and comprises a vibration system and a magnetic circuit system, the vibration system comprises a diaphragm, a first voice coil and a second voice coil, the diaphragm surrounds the hollow channel, the first voice coil is connected to the diaphragm and surrounds the hollow channel, and the second voice coil is connected to the diaphragm and surrounds the outer periphery of the first voice coil. The magnetic circuit system has a magnetic gap, and at least part of the first voice coil and at least part of the second voice coil are located in the magnetic gap; the magnetic circuit system is used for driving the first voice coil and the second voice coil to move to make the diaphragm vibrate to produce sound.

2. The electro-acoustic transducer of claim 1, wherein, The diaphragm comprises an inner folding ring, a first flat portion, a convex membrane top, a second flat portion and an outer folding ring which are connected in sequence, the inner folding ring surrounds the hollow channel, and the inner folding ring, the convex membrane top and the outer folding ring are all outwardly convex relative to the same side of the first flat portion, the first voice coil is connected to the first flat portion, and the second voice coil is connected to the second flat portion.

3. The electro-acoustic transducer of claim 2, wherein, The ratio between the area of the normal projection of the convex membrane top on a first reference plane and the area of the normal projection of the diaphragm as a whole on the first reference plane is between 0.2 and 0.7, wherein the first reference plane is perpendicular to the axial direction of the electro-acoustic transducer.

4. The electro-acoustic transducer of claim 2, wherein, The convex membrane top is an outwardly convex arc structure or a planar structure.

5. The electro-acoustic transducer of claim 3, wherein, The ratio between the area of the normal projection of the outer folding ring on the first reference plane and the area of the normal projection of the diaphragm as a whole on the first reference plane is between 0.2 and 0.

35.

6. The electro-acoustic transducer of claim 3, wherein, The ratio between the area of the normal projection of the inner folding ring on the first reference plane and the area of the normal projection of the diaphragm as a whole on the first reference plane is between 0.1 and 0.

2.

7. The electro-acoustic transducer of claim 2, wherein, The inner folding ring is an outwardly convex arc structure, and / or the outer folding ring is an outwardly convex arc structure.

8. The electro-acoustic transducer of claim 2, wherein, The inner folding ring and / or the outer folding ring are provided with a texture structure.

9. The electro-acoustic transducer of claim 2, wherein, The inner folding ring, the convex membrane top and the outer folding ring are located on different sides of the first flat portion relative to the first voice coil and the second voice coil.

10. The electro-acoustic transducer of claim 2, wherein, The electro-acoustic transducer further comprises a basket, the basket comprises an annular basket inner side wall and an annular basket outer side wall, the basket inner side wall defines the hollow channel, and the basket outer side wall surrounds the basket inner side wall. The diaphragm further comprises a first connecting portion and a second connecting portion, the first connecting portion is connected to the inner folding ring and surrounds the hollow channel, and the second connecting portion is connected to the outer folding ring; the first connecting portion is connected to the basket inner side wall, and the second connecting portion is connected to the basket outer side wall.

11. The electro-acoustic transducer of claim 10, wherein, The ratio between the minimum diameter of the basket inner side wall and the maximum diameter of the basket outer side wall is between 0.1 and 0.

5.

12. The electro-acoustic transducer of claim 10, wherein, The electro-acoustic transducer further comprises a first fixing ring and a second fixing ring, the first fixing ring fixedly connects the first connecting portion and the basket inner side wall, and the second fixing ring fixedly connects the second connecting portion and the basket outer side wall.

13. The electro-acoustic transducer of claim 12, wherein, The ratio between the maximum outer diameter of the second fixing ring and the maximum outer diameter of the basket outer side wall is between 0.7 and 1. And / or, the ratio between the minimum inner diameter of the first retaining ring and the maximum outer diameter of the outer wall of the basin frame is between 0.1 and 0.

5.

14. The electro-acoustic transducer of claim 10, wherein, The magnetic circuit system includes a first magnetic element disposed on the basket frame and surrounding the inner sidewall of the basket frame. A first magnetic gap and a second magnetic gap are formed between the first magnetic element and the basket frame. The first magnetic gap surrounds the inner sidewall of the basket frame, and the second magnetic gap surrounds the outer periphery of the first magnetic gap. One end of the first voice coil extends to the first magnetic gap, and one end of the second voice coil extends to the second magnetic gap.

15. The electro-acoustic transducer of claim 10, wherein, The magnetic circuit system includes a second magnetic element, a third magnetic element, and a fourth magnetic element respectively disposed on the basket frame. The second magnetic element surrounds the inner sidewall of the basket frame, the third magnetic element surrounds the second magnetic element, and the fourth magnetic element surrounds the third magnetic element. A third magnetic gap is formed between the second magnetic element and the third magnetic element, and a fourth magnetic gap is formed between the third magnetic element and the fourth magnetic element. One end of the first voice coil extends to the third magnetic gap, and one end of the second voice coil extends to the fourth magnetic gap.

16. The electro-acoustic transducer of claim 10, wherein, The basket frame is provided with a rear tuning hole, which is connected to the magnetic gap of the magnetic circuit system.

17. An earphone, characterized by The earphone includes a housing and an electroacoustic transducer as described in any one of claims 1-16, wherein the electroacoustic transducer is disposed in the housing.

18. The earphone of claim 17, wherein, The headphones also include an opening and closing mechanism; The housing has a first sound outlet located on the side of the housing facing the ear. The hollow channel communicates with the first sound outlet. The housing also includes an outer wall opposite to the electroacoustic transducer. The outer wall has end faces that connect the hollow channel to the external environment. The opening and closing component is used to open or close the connection between the first sound outlet and the external environment.

19. The earphone of claim 18, wherein, The housing has a first cavity located between the electroacoustic transducer and the end face, and the end face is connected to the hollow channel through the first cavity.

20. The earphone of claim 19, wherein, The opening and closing component is disposed in the first cavity of the housing and is located at the connection between the end face and the hollow channel, and is used to open or close the connection between the end face and the hollow channel.

21. The earphone of claim 19, wherein, The distance between the end face and the first surface of the electroacoustic transducer facing the end face in the axial direction of the electroacoustic transducer is greater than or equal to 0.5 mm and less than or equal to 10 mm.

22. The earphone of claim 21, wherein, The orthographic projection of the hollow channel onto the outer side wall at least partially overlaps with the end face; Alternatively, the orthographic projection of the hollow channel onto the outer side wall does not overlap with the end face.

23. The earphone of claim 22, wherein, The distance between the central axis of the end face and the central axis of the hollow channel in the radial direction of the electroacoustic transducer is greater than or equal to 0 mm and less than or equal to 36 mm.

24. The earphone of claim 19, wherein, A first channel is also formed within the first cavity, the first channel connecting the end face and the hollow channel.

25. The earphone of claim 24, wherein, The outer wall is formed with a first annular protrusion that surrounds the end face and protrudes toward the hollow channel, the first annular protrusion defining the first channel.

26. The earphone of claim 25, wherein, In the direction of the first annular protrusion toward the hollow channel, the height of the first annular protrusion is greater than or equal to 0 mm and less than or equal to 10 mm.

27. The earphone of claim 24, wherein, The minimum cross-sectional area of ​​the first channel is greater than or equal to the maximum cross-sectional area of ​​the hollow channel.

28. The earphone of claim 19, wherein, The housing has a first rear sound outlet, which is located on the side of the housing away from the ear, and the first rear sound outlet is connected to the first cavity.

29. The earphone of claim 19, wherein, The earphone also includes a middle shell, which covers the electroacoustic transducer. A second cavity is defined between the middle shell and the electroacoustic transducer. The second cavity is connected to the hollow channel. The middle shell is provided with a connecting hole, which connects the second cavity and the end hole.

30. The earphone of claim 19, wherein, The earphone also includes a middle shell, which covers the electroacoustic transducer to define a second cavity and a second channel that are not interconnected. The second channel is connected to the hollow channel. The middle shell is provided with a connecting hole that is connected to the second channel and the connecting hole is connected to the end face.

31. The earphone of claim 30, wherein, The middle shell includes a bottom wall disposed opposite to the electroacoustic transducer. The connecting hole is disposed on the bottom wall of the middle shell. The bottom wall of the middle shell has a second annular protrusion that surrounds the connecting hole and protrudes toward the hollow channel. The second annular protrusion defines a second channel that communicates with the hollow channel.

32. The earphone of claim 31, wherein, In the direction of the second annular protrusion toward the hollow channel, the height of the second annular protrusion is greater than or equal to 0 mm and less than or equal to 10 mm.

33. The earphone of claim 31, wherein, The minimum cross-sectional area of ​​the second channel is greater than or equal to the maximum cross-sectional area of ​​the hollow channel.

34. The earphone of claim 31, wherein, The middle shell divides the first cavity into a second cavity and a third cavity. The shell is also provided with a second rear sound outlet that communicates with the third cavity. The second rear sound outlet is located on the side of the shell away from the ear. The middle shell is provided with a first sound outlet communication hole that communicates with the second cavity and the third cavity.

35. The earphone of claim 31, wherein, The bottom wall of the middle shell is attached to the outer wall.

36. The earphone of claim 35, wherein, The middle shell divides the first cavity into the second cavity and the third cavity. The bottom wall of the middle shell is provided with a second sound outlet communication hole that communicates with the second cavity. The outer wall is provided with a third rear sound outlet hole that communicates with the second sound outlet communication hole.

37. The earphone according to any one of claims 17-36, wherein, The minimum cross-sectional area of ​​the first sound outlet is greater than or equal to 15 square millimeters.

38. The earphone according to any one of claims 17-36, wherein, The orthographic projection of the first sound outlet on the first reference plane at least partially overlaps with the orthographic projection of the hollow channel on the first reference plane, wherein the first reference plane is perpendicular to the central axis of the electroacoustic transducer.

39. The earphone of claim 38, wherein, The area of ​​the first sound outlet hole projected onto the first reference plane is greater than the area of ​​the hollow channel projected onto the first reference plane.

40. The earphone of claim 39, wherein, The electroacoustic transducer includes a ring-shaped diaphragm surrounding the hollow channel, and the orthographic projection of the first sound outlet on the first reference plane at least partially overlaps with the orthographic projection of the diaphragm on the first reference plane.

41. The earphone of claim 40, wherein, The earphone also includes a protective component with a mesh structure, which is disposed at the first sound outlet.

42. The earphone according to any one of claims 17-36, wherein, The minimum cross-sectional area of ​​the hollow channel is greater than or equal to 5 square millimeters.

43. The earphone according to any one of claims 17-36, wherein, The minimum cross-sectional area of ​​the end face is greater than or equal to 15 square millimeters.

44. The earphone according to any one of claims 17-36, wherein, A second reference plane is established using the three regions of the ear: the tragus, the antitragus, and the antihelix. The projection of the first sound hole and / or the end face on the second reference plane along the coronal axis is located on or covers the region formed by the projection of the concha, antihelix, antitragus, and tragus on the second reference plane along the coronal axis.

45. The earphone of claim 44, wherein, The projection of the hollow channel onto the second reference plane along the coronal axis and the projection of the ear canal onto the second reference plane along the coronal axis have a first minimum distance. The projection of the terminal face on the second reference plane along the coronal axis and the projection of the ear canal on the second reference plane along the coronal axis have a second minimum distance, wherein the first minimum distance is less than or equal to the second minimum distance.

46. The earphone of claim 17, wherein, The opening and closing component is disposed on the housing and located at the hollow channel of the electroacoustic transducer, and is used to open or close the hollow channel; Alternatively, the opening and closing component is disposed on the housing and located on one side of the first sound outlet, for opening or closing the first sound outlet; Alternatively, the opening and closing component is disposed on the housing and located on one side of the end face, for opening or closing the end face.

47. The earphone of claim 17, wherein, The housing has a first sound outlet and an end face. The first sound outlet is located on the side of the housing facing the ear and is connected to the hollow channel. The end face is located on the side of the housing away from the ear and is connected to the external environment and the hollow channel, respectively. The earphone has a first resonant cavity formed on the side facing the ear. The first resonant cavity is connected to the first sound outlet. When the earphone is worn, the first resonant cavity covers the ear. The first resonant cavity is connected to the end face through the hollow channel, so that the first resonant cavity, the hollow channel and the end face form a first Helmholtz resonance system. A second resonant cavity is also formed inside the housing. A second sound outlet is provided on the side of the housing away from the ear. The second resonant cavity is connected to the rear tuning hole of the electroacoustic transducer and the second sound outlet. The second resonant cavity and the second sound outlet form a second Helmholtz resonance system. The end face and the second sound outlet hole constitute a dipole sound source within a preset frequency range.

48. The earphone of claim 47, wherein, The first Helmholtz resonance system has a first Helmholtz resonance frequency f1, and the second Helmholtz resonance system has a second Helmholtz resonance frequency f2; Where |f1-f2|≤300Hz.

49. The earphone of claim 47, wherein, The first Helmholtz resonance system has a first Helmholtz resonance frequency f1, and the second Helmholtz resonance system has a second Helmholtz resonance frequency f2, wherein f1 ≥ 5000 Hz and f2 ≥ 5000 Hz.

50. The earphone of claim 48 or 49, wherein, A connecting channel is formed inside the housing, and the connecting through hole connects the hollow channel and the end hole.

51. The earphone of claim 50, wherein, The housing also includes an outer wall disposed opposite to the electroacoustic transducer, the end face is disposed on the outer wall, the outer wall is formed with a first annular protrusion surrounding the end face and protruding toward the hollow channel, the first annular protrusion defining the communication channel.

52. The earphone of claim 51, wherein, The housing also includes an outer side wall disposed opposite to the electroacoustic transducer, and the end face hole is disposed on the outer side wall. The earphone also includes a middle shell, which covers the electroacoustic transducer to define a middle shell channel and the second resonant cavity that are not interconnected. The middle shell channel is connected to the hollow channel. The middle shell is provided with a connecting hole that is connected to the middle shell channel. The connecting hole is connected to the end face hole. The middle shell channel and the connecting hole define the connecting channel.

53. The earphone of claim 52, wherein, The middle shell includes a bottom wall disposed opposite to the electroacoustic transducer, the connecting hole is disposed on the bottom wall of the middle shell, and the bottom wall of the middle shell forms a second annular protrusion that surrounds the connecting hole and protrudes toward the hollow channel, the second annular protrusion defining the middle shell channel.

54. The earphone of claim 53, wherein, The middle shell is provided with a sound outlet communication hole that communicates with the second resonant cavity, and the sound outlet communication hole is connected to the second sound outlet hole.

55. The earphone of claim 54, wherein, The sound outlet communication hole is disposed on the bottom wall of the middle shell, and the second sound outlet hole is disposed on the outer wall in the area opposite to the sound outlet communication hole.

56. The earphone of claim 55, wherein, The bottom wall of the middle shell is attached to the outer wall.

57. The earphone of any one of claims 50-56, wherein, The hollow channel, the connecting channel, and the end face together define a second channel, the length of which is less than or equal to 43 mm.

58. The earphone of claim 48 or 49, wherein, The volume of the first resonant cavity is less than or equal to 55 cubic centimeters.

59. The earphone of claim 58, wherein, The volume of the second resonant cavity is between 6 cubic centimeters and 55 cubic centimeters.

60. The earphone of claim 57, wherein, The opening area of ​​the second sound hole is greater than or equal to 15 square millimeters.

61. The earphone of claim 58, wherein, Along the axial direction of the electroacoustic transducer, the length of the second sound outlet is between 1 mm and 55 mm.

62. The earphone of claim 48 or 49, wherein, The minimum radial distance between the end face and the second sound outlet hole of the electroacoustic transducer is between 7 mm and 28 mm.

63. An earphone, comprising: The device includes a housing, an electroacoustic transducer, and an opening / closing assembly. The electroacoustic transducer is disposed within the housing and has a hollow channel extending along its own axial direction. The housing has a first sound outlet located on the side of the housing facing the ear, and the hollow channel communicates with the first sound outlet. The housing also includes an outer side wall disposed opposite to the electroacoustic transducer, and the outer side wall has end faces that connect the hollow channel to the external environment. The opening and closing component is used to open or close the connection between the first sound outlet and the external environment.

64. An earphone, comprising: It includes a housing and an electroacoustic transducer, wherein the electroacoustic transducer is disposed inside the housing and the electroacoustic transducer is provided with a hollow channel extending along its own axial direction. The housing has a first sound outlet and an end face. The first sound outlet is located on the side of the housing facing the ear and is connected to the hollow channel. The end face is located on the side of the housing away from the ear and is connected to the external environment and the hollow channel, respectively. The earphone has a first resonant cavity formed on the side facing the ear. The first resonant cavity is connected to the first sound outlet. When the earphone is worn, the first resonant cavity covers the ear. The first resonant cavity is connected to the end face through the hollow channel, so that the first resonant cavity, the hollow channel and the end face form a first Helmholtz resonance system. A second resonant cavity is also formed inside the housing. A second sound outlet is provided on the side of the housing away from the ear. The second resonant cavity is connected to the rear tuning hole of the electroacoustic transducer and the second sound outlet. The second resonant cavity and the second sound outlet form a second Helmholtz resonance system. The end face and the second sound outlet hole constitute a dipole sound source within a preset frequency range.

Images