CN113242485B

CN113242485B - In-ear earphone

Info

Publication number: CN113242485B
Application number: CN202110486329.3A
Authority: CN
Inventors: 王苗苗; 郭晓冬
Original assignee: Goertek Inc
Current assignee: Goertek Inc
Priority date: 2021-04-30
Filing date: 2021-04-30
Publication date: 2022-08-19
Anticipated expiration: 2041-04-30
Also published as: CN113242485A; WO2022227629A1

Abstract

The invention discloses an in-ear earphone which comprises a shell with a containing space and a sounding monomer arranged in the containing space, wherein the containing space is divided into an earphone front cavity and an earphone rear cavity by the sounding monomer; the sounding unit comprises a shell with a sounding hole and a sounding unit arranged in the shell; a front sound cavity is formed between a vibrating diaphragm of the sound generating unit and the shell, and the front sound cavity communicated with the sound generating hole is communicated with the front cavity of the earphone; the inner wall of the shell facing the front sound cavity is provided with a sunken cavity, and an opening of the sunken cavity is hermetically covered with a vibrating diaphragm. The in-ear earphone disclosed by the invention can effectively reduce or avoid the external auditory canal resonance caused by playing the sound with the preset frequency, thereby reducing or avoiding the abnormal sound caused by the external auditory canal resonance.

Description

In-ear earphone

Technical Field

The invention relates to the technical field of electroacoustic conversion, in particular to an in-ear earphone.

Background

The earphone includes the shell and locates the sound production monomer in the shell, and the sound production monomer includes magnetic circuit component and vibration subassembly, and the voice coil loudspeaker voice coil in the vibration subassembly passes through the voice coil loudspeaker voice coil lead wire to be connected with external power source, and the voice coil loudspeaker voice coil of circular telegram atress produces the vibration in magnetic circuit system's magnetic field, thereby the vibration of voice coil loudspeaker voice coil has driven the vibration of vibrating diaphragm and has produced resonance and make sound with air on every side.

The in-ear earphone is perfectly coupled with the external auditory canal of human ear, which brings the advantages of higher sensitivity and physical noise reduction, but the structure brings about the problem that the resonance condition of the external auditory canal changes after the earphone is installed, and the resonance frequency shifts, which brings about great loss to the frequency characteristic of the earphone. When the in-ear headphone is worn, a sound near 6kHz is emphasized by the resonance mode of the closed tubes at both ends, and the sound becomes quasi-ringing, which causes the wearer to hear a buzzing abnormal sound.

The reason why the above problems are caused is that: before a human ear wears the in-ear earphone, the external auditory canal is an acoustic pipeline with one end open and communicated with the external air and the other end closed through the eardrum, namely, the acoustic pipeline with one end closed and the other end open can be simply understood as an acoustic pipeline with one end closed, and the acoustic pipeline has the own resonance frequency. In conjunction with the SPL curve shown in FIG. 11, the dotted line indicates that the sound pressure level at the tympanic membrane position when the in-ear headphone is not worn has resonance peaks at 2.8 to 3.4kHz and 8.5 to 10.2 kHz. When the in-ear earphone is worn, the originally open end of the external auditory canal is shielded by the earphone, and the state of the closed tube at two ends is changed from the state of the closed tube at one end to the state of the closed tube at two ends, namely an acoustic tube with closed tubes at two ends. The resonance frequencies of the acoustic duct with both closed tubes and the acoustic duct with one closed tube are different, and as shown by the SPL curve shown by the solid line in fig. 11, the sound pressure level at the tympanic membrane position when the in-ear headphone is worn is affected by the resonance of the closed tube in the external auditory canal, and the resonance peak positions are shifted to the vicinity of 6kHz and the vicinity of 12 kHz. Therefore, the sound near 6kHz is emphasized by the resonance mode of the both closed tubes, and becomes quasi-ringing, which causes the wearer to hear a buzzing sound.

Therefore, it is desirable to provide a new sounding unit to solve the above technical problems.

Disclosure of Invention

The invention mainly aims to provide an in-ear earphone, and aims to solve the technical problems that after the in-ear earphone is worn, the resonance frequency of an acoustic pipeline in a closed tube state at two ends of an external auditory canal is deviated, and a user hears abnormal sound in partial frequency bands.

In order to achieve the above object, the present invention provides an in-ear earphone, which includes a housing having an accommodation space and a sound generating unit installed in the accommodation space, wherein the sound generating unit divides the accommodation space into an earphone front cavity and an earphone rear cavity;

the sounding unit comprises a shell with a sounding hole and a sounding unit arranged in the shell;

a front sound cavity is formed between the vibrating diaphragm of the sound production unit and the shell, and the sound outlet hole is communicated with the front sound cavity and the front cavity of the earphone;

the inner wall of the shell facing the front sound cavity is provided with a sunken cavity, and an opening of the sunken cavity is hermetically covered with a vibrating diaphragm.

Optionally, the front acoustic cavity, the recessed cavity and the vibrating diaphragm form an acoustic structure, and the resonant frequency of the acoustic structure is less than or equal to 7.5kHz and less than or equal to 5.0 kHz.

Optionally, the sounding unit comprises two sounding units arranged in the shell, vibrating diaphragms of the two sounding units are oppositely arranged at intervals,

the casing is including locating two the septum piece between sound producing unit's the vibrating diaphragm, the septum piece will two separate for the chamber before first preceding chamber and the second between the sound producing unit, the chamber is before the second is the preceding sound chamber, sunken chamber certainly the septum piece face to the chamber before the second one face the first preceding chamber is sunken to be formed.

Optionally, the sound outlet hole is communicated with the first front cavity;

the middle partition is provided with a vent hole communicated with the first front cavity and the second front cavity, the vent hole is formed in one end, close to the sound outlet hole, of the middle partition, and the second front cavity, the vent hole, the first front cavity and the sound outlet hole are sequentially communicated.

Optionally, the casing further includes an upper casing and a lower casing disposed at opposite sides of the middle partition, the upper casing accommodates the sound generating unit forming the first front cavity, and the lower casing accommodates the sound generating unit forming the second front cavity;

the middle partition piece comprises a partition plate and a hollow outer frame, the partition plate and the hollow outer frame are respectively arranged at intervals relative to the sounding unit, the outer peripheral side of the outer frame is respectively connected with the upper shell and the lower shell, the outer peripheral side of the partition plate is connected with the outer frame, and the partition plate forms the concave cavity.

Optionally, the partition plate protrudes towards the first front cavity to form the recessed cavity.

Optionally, a vibration direction of a diaphragm of the sound generating unit is perpendicular to a sound emitting direction of the sound emitting hole.

Optionally, one of the two sound units is a bass sound unit, and the other is a bass sound unit or a treble sound unit.

Optionally, the sound generating unit forming the first front cavity with the middle partition is a high pitch sound generating unit, and the sound generating unit forming the second front cavity with the middle partition is a low pitch sound generating unit.

Optionally, the housing is further provided with a pressure equalizing hole communicated with the first front cavity and/or the second front cavity, and the pressure equalizing hole is communicated with the rear cavity of the earphone.

According to the in-ear earphone, the concave cavity is arranged on the inner wall of the shell of the sounding unit facing the front sound cavity, the opening of the concave cavity is hermetically covered with the vibrating diaphragm, the vibrating diaphragm and the air of the front sound cavity are in parallel connection, and the resonant frequency f is close to the resonant frequency of an acoustic pipeline in a closed tube state at two ends of an external auditory canal when a human ear wears the in-ear earphone by adjusting the resonant frequency of an acoustic structure consisting of the vibrating diaphragm, the front sound cavity and the concave cavity, so that the purpose of inhibiting the peak value of the resonant frequency of the acoustic pipeline in the closed tube state at two ends is achieved, and meanwhile, the whole volume can be prevented from being reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic cross-sectional view of an in-ear headphone according to an embodiment of the present invention;

fig. 2 is a schematic cross-sectional view of an in-ear headphone according to another embodiment of the present invention;

FIG. 3 is a partially disassembled view of the sounding unit in the embodiment of FIG. 2;

FIG. 4 is a schematic sectional view of the sounding unit in the embodiment of FIG. 2;

FIG. 5 is a schematic diagram of a partial cross-sectional structure of the sounding unit in the embodiment of FIG. 2;

fig. 6 is a graph of the impedance of the sound producing unit of the in-ear headphone of fig. 1;

FIG. 7 is a graph of sound pressure levels for an in-ear headphone of FIG. 1 when not worn by a human ear;

FIG. 8 is a schematic cross-sectional view of a sounding unit according to the present invention;

FIG. 9 is a schematic cross-sectional view of another comparative example of the sound generating unit of the present invention;

FIG. 10 is a graph of the frequency response of the sound generating unit shown in FIGS. 3, 8 and 9;

FIG. 11 is a graph of sound pressure levels for a human ear when no in-ear headphone is worn and when a prior art in-ear headphone is worn in the external auditory canal.

Description of embodiments reference numerals:

reference numerals	Name (R)	Reference numerals	Name (R)
				10	In-ear earphone	101	Outer cover
103	Earphone front cavity	104	Earphone rear cavity
				100	Sound monomer	1	Shell body
11	Upper casing	12	Sound outlet hole
				13	Lower case	14	Pressure relief hole
16	Pressure equalizing hole	3	Septum
				31	Outer frame	32	Vent hole
33	Partition board	34	Cavity
				35	Vibrating diaphragm	36	Sound outlet gap
5	Sound production unit	51	Vibrating diaphragm
				52	First front cavity	54	Second front cavity

The implementation, functional features and advantages of the present invention will be further described with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive step based on the embodiments of the present invention, are within the scope of protection of the present invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

Referring to fig. 1, the present invention is directed to an in-ear headphone 10. The in-ear earphone 10 comprises a housing 101 with a containing space and a sound generating unit 100 arranged in the containing space, wherein the containing space is divided into an earphone front cavity 103 and an earphone rear cavity 104 by the sound generating unit 100; the sound generating unit 100 comprises a shell 1 with a sound outlet hole 12 and a sound generating unit 5 arranged in the shell 1; a front sound cavity 54 is formed between the diaphragm 51 of the sound generating unit 5 and the housing 1, and the front sound cavity 54 communicated with the sound outlet hole 12 is connected with the front cavity 103 of the earphone; the inner wall of the shell 1 facing the front sound cavity 54 is provided with a concave cavity 34, and the opening of the concave cavity 34 is hermetically covered with a vibrating diaphragm 35.

The acoustic structure in the following description is, unless otherwise specified, an acoustic structure composed of the front acoustic cavity 54, the concave cavity 34, and the diaphragm 35, and an impedance curve of the acoustic structure is a high-order model. The resonant frequency, the total acoustic compliance and the total acoustic mass of the acoustic structure can be calculated by the following formulas:

wherein fb is the resonant frequency of the acoustic structure; cb is the total acoustic compliance of the acoustic structure; mb is the total acoustic mass of the acoustic structure; cas is the equivalent acoustic compliance of the sound generating unit 5; cab: equivalent acoustic compliance of the air in the front acoustic chamber 54; cap is the equivalent acoustic compliance of the diaphragm 35 and the cavity 34; mas: the vibration system equivalent acoustic mass of the sound generating unit 5; mab is the equivalent acoustic mass of the air duct within the front acoustic chamber 54; map is the equivalent acoustic mass of the diaphragm 35.

It can thus be determined that the resonant frequency of the acoustic structure is related to the sound generating unit 5, the diaphragm 35, the cavity 34, etc., please refer to fig. 6, which is an impedance curve of the acoustic structure composed of the front sound cavity, the cavity 34 and the diaphragm 35, the impedance curve forming two distinct peaks. The frequency of the peak with a lower frequency can be denoted as fl, the frequency corresponding to the peak with a higher frequency can be denoted as fh, the position of the trough can be denoted as fb, and fb is the resonant frequency of the acoustic structure composed of the front acoustic cavity 54, the concave cavity 34 and the vibrating diaphragm 35. The resonance frequency of the acoustic structure can be changed to be close to the resonance frequency of the acoustic pipeline in the closed tube state at the two ends of the external auditory canal when the in-ear earphone 10 is worn by the human ear by adjusting the material and the size of the vibrating diaphragm 35, and the resonance frequency fb in the trough state can achieve the purpose of suppressing the resonance frequency peak value of the acoustic pipeline in the closed tube state at the two ends because the impedance curve is in direct proportion to the sound pressure level curve, so that the abnormal sound ringing sound is reduced or eliminated, and the whole volume is not reduced. Referring to fig. 7, the dotted line is a sound pressure level curve of the human ear without wearing the earphone, and the solid line is a sound pressure level curve of the in-ear earphone with the vibrating diaphragm 35. In this figure, it can be observed that the peak value of the resonance frequency at around 6kHz is significantly reduced in the case of wearing the in-ear headphone in which the vibrating diaphragm 35 is provided.

Further, the front acoustic cavity 54, the recessed cavity 34 and the vibrating diaphragm 35 constitute an acoustic structure, and the resonance frequency of the acoustic structure is 5.0kHz to 7.5 kHz. Due to individual differences, different human ears have different shapes of auditory canals, and a large number of experiments prove that the resonance frequency of the acoustic pipeline in a closed tube state at two ends of the external auditory canal when the human ears are worn in the ear earphones is between 5.0kHz and 7.5kHz, so that a person skilled in the art can select a proper material and size of the vibrating diaphragm 35 and change the size of the front sound cavity 54, the size of the sound generating unit 5 and the like so as to ensure that the resonance frequency of the acoustic structure formed by the front sound cavity, the concave cavity 34 and the vibrating diaphragm 35 is between 5.0kHz and 7.5 kHz.

Referring to fig. 2, 3, 4 and 5, the sound generating unit 100 includes two sound generating units 5 disposed in the housing 1, the diaphragms 51 of the two sound generating units 5 are disposed at an interval, the housing 1 includes a partition 3 disposed between the diaphragms 51 of the two sound generating units 5, the partition 3 divides the space between the two sound generating units 5 into a first front cavity 52 and a second front cavity 54, the second front cavity 54 is the front sound cavity 54, and the recessed cavity 34 is formed by recessing from a surface of the partition 3 facing the second front cavity 54 toward the first front cavity 52. By means of the two sound units 5, the overall bandwidth of the sound unit 100 can be further expanded.

Further, the sound outlet hole 12 communicates with the first front chamber 52; the partition 3 is provided with a vent hole 32 communicating the first front cavity 52 and the second front cavity 54, the vent hole 32 is provided at one end of the partition 3 close to the sound outlet hole 12, and the second front cavity 54, the vent hole 32, the first front cavity 52 and the sound outlet hole 12 are sequentially communicated.

When the sound generating unit 5 forming the first front cavity 52 vibrates to generate sound, the airflow directly passes through the sound outlet hole 12 to reach the outside, so that the outside receives the sound generated by the sound generating unit 5 forming the first front cavity 52; when the sound generating unit 5 forming the second front cavity 54 vibrates to generate sound, the airflow enters the first front cavity 52 through the vent hole 32 and then reaches the outside through the sound outlet hole 12, so that the outside receives the sound generated by the sound generating unit 5 forming the second front cavity 54. For the sound generating unit 5 forming the first front cavity 52 with the septum 3, when the sound generating unit 5 works, the vent hole 32 on the septum 3 and the second front cavity 54 jointly generate a helmholtz resonance effect, so that the bandwidth of the sound generating unit 5 can be expanded, and the frequency dividing point of the sound generating unit 5 can move to a high frequency; with the sound unit 5 having the second front chamber 54 formed with the spacer 3, when the sound unit 5 is operated, the part of the first front chamber 52 away from the sound outlet hole 12 generates the helmholtz resonance effect, and thus the bandwidth of the sound unit 5 itself can be widened and the frequency dividing point thereof can be shifted to a high frequency, so that the design described above can improve the high frequency performance and the ductility of the entire sound generating unit 100.

Referring to fig. 8 and 9, the comparative example shown in fig. 8 is different from the sound generating device of the present invention in that the septum 3 does not have the vent hole 32 and the two sound generating units 5 have the front cavities independent of each other in the comparative example shown in fig. 8; the comparative example shown in fig. 9 is different from the sound generating device of the present invention in that the spacer 3 is not provided and two sound generating units 5 share one front chamber in the comparative example shown in fig. 9. Referring to fig. 10, a curve L2 is a frequency response curve of the sound generating device of the comparative example shown in fig. 8, a curve L3 is a frequency response curve of the sound generating device of the comparative example shown in fig. 9, and a curve L1 is a frequency response curve of the sound generating device according to an embodiment of the present invention. It can be seen from the curves L1, L2, and L3 that the sound generating device of the present invention has a larger bandwidth in the high frequency range.

With reference to fig. 2, 3 and 4, the casing 1 further includes an upper casing 11 and a lower casing 13 disposed on opposite sides of the partition 3, the upper casing 11 houses the sound generating unit 5 forming the first front cavity 52, and the lower casing 13 houses the sound generating unit 5 forming the second front cavity 54; the partition member 3 includes a partition plate 33 and a hollow outer frame 31 which are respectively disposed opposite to the sound emission unit 5 at an interval, outer peripheral sides of the outer frame 31 are respectively connected to the upper case 11 and the lower case 13, outer peripheral sides of the partition plate 33 are connected to the outer frame 31, and the partition plate 33 forms the concave cavity 34.

Further, one of the two sound units 5 is a bass sound unit 5, and the other is the bass sound unit 5 or the treble sound unit 5. The skilled person can select which sound units 5 the two sound units 5 are respectively, according to the needs. When the full-frequency effect is needed to be realized, the auditory experience of a user is increased, and the combination of the bass sounding unit 5 and the treble sounding unit 5 can be adopted; when the bass effect needs to be enhanced, the low frequency is more vigorous, and the combination of the double-bass sound producing units 5 can be adopted.

Still further, the sound generating unit 5 forming the first front chamber 52 with the partition 3 is a high pitch sound generating unit 5, and the sound generating unit 5 forming the second front chamber 54 with the partition 3 is a low pitch sound generating unit 5. The amplitude of the bass sound unit 5 is larger than that of the treble sound unit 5, and the air thrust in the second front chamber 54 is larger when vibrating, thereby facilitating the air flow to flow out of the sound outlet hole 12.

For convenience of description, the following description will be made with reference to the sound unit 5 forming the first front chamber 52 as the treble sound unit 5 and the sound unit 5 forming the second front chamber 54 as the bass sound unit 5, and it will be understood by those skilled in the art that the following description of relevant features does not constitute a limitation to the two sound units 5, specifically, the treble sound unit 5 or the bass sound unit 5. In this embodiment, the casing 1 includes an upper casing 11 and a lower casing 13, which are matched with each other, the high-pitch sound unit 5 is accommodated in the upper casing 11, the low-pitch sound unit 5 is accommodated in the lower casing 13, and the upper casing 11 and the lower casing 13 are respectively provided with a pressure relief hole 14 communicated with the high-pitch sound unit 5 or the low-pitch sound unit 5, so as to facilitate the vibration of the diaphragm 51. The outer frame 31 may be supported on a frame of the treble sound unit 5 or a frame of the bass sound unit 5. The size of the first front chamber 52 and the second front chamber 54 can be adjusted by adjusting the connection position of the partition 33 and the outer frame 31 to adjust the division of the space between the two sound emitting units 5.

Further, the partition 33 protrudes toward the first front chamber 52 to form a concave chamber, so that the first front chamber 52 is enlarged as much as possible under the condition that the total space of the first front chamber 52 and the second front chamber 54 is constant, so as to ensure the vibration sound of the bass sound unit 5.

The vibrating diaphragm 51 of the sound emitting unit 5 vibrates in a direction perpendicular to the sound emitting direction of the sound emitting hole 12. The vent hole 32 is opened on the partition plate 33, and the vent hole 32 is arranged at one end of the recessed cavity close to the sound outlet hole 12. So that the airflow of the second front chamber 54 can be rapidly propagated through the sound outlet hole 12.

The outer frame 31 is recessed to form a sound outlet notch 36 communicating the sound outlet hole 12 and the first front chamber 52 near one end of the sound generating unit 5 forming the first front chamber 52. The high pitch sound unit 5 is disposed on the outer frame 31, and the passage formed by the high pitch sound unit 5 and the sound outlet notch 36 communicates the sound outlet 12 and the first front chamber 52.

Further, the housing 1 is further provided with a pressure equalizing hole 16 communicated with the first front cavity 52 and/or the second front cavity 54, and the pressure equalizing hole 16 is communicated with the earphone rear cavity 104.

The in-ear headphone 10 comprises a housing 101 adapted to the concha cavity of the user, wherein one end of the in-ear headphone 10 contacting with the top of the concha cavity of the user is the top of the housing 101, one end of the in-ear headphone 10 contacting with the bottom of the concha cavity of the user is the bottom of the housing 101, and a sound outlet 102 facing the external auditory canal of the user is formed in the housing 101. The intercommunication of sound outlet 102 and earphone front cavity 103 through setting up pressure-equalizing hole 16 thereby the sound that makes the earphone is heard more balancedly, and the vibrating diaphragm 51 vibration is more harmonious, possess better transient state effect, avoids wearing in-process vibrating diaphragm 51 abnormal sound. By directly forming the pressure equalizing hole 16 on the housing 1, additional space occupation is avoided, and the miniaturization of the sounding unit 100 is facilitated.

When the pressure equalizing hole 16 is formed in the casing 1, the pressure releasing hole 14 is further formed in the casing 1, the pressure equalizing hole 16 can directly adjust the air pressure balance among the first front cavity 52, the second front cavity 54 and the rear cavity 104 of the earphone, and the pressure releasing hole 14 can directly adjust the air pressure balance among the interior of each sound generating unit 5 and the rear cavity 104 of the earphone.

The two sound emitting units 5 may be stacked in a direction perpendicular to the bottom of the housing 101 to the top of the housing 101. The two sound emitting units 5 may also be stacked in a direction from the bottom of the housing 101 to the top of the housing 101. A person skilled in the art can determine in which way to set the positional relationship of the two sound emission units 5 in the casing 101, according to the space reserved for the sound emission unit 100 in the casing 101 and the size of the sound emission unit 100.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. An in-ear earphone is characterized by comprising a shell with a containing space and a sound generating unit arranged in the containing space, wherein the containing space is divided into an earphone front cavity and an earphone rear cavity by the sound generating unit;

a sunken cavity is formed in the inner wall, facing the front sound cavity, of the shell, and an opening of the sunken cavity is covered with a vibrating diaphragm in a sealing mode;

the sound production monomer is including locating two sound production units in the casing, two the relative interval of vibrating diaphragm of sound production unit sets up, the casing is including locating two well septum piece between the vibrating diaphragm of sound production unit, well septum piece is with two separate for chamber before first and the second between the sound production unit, the chamber does before the second preceding sound chamber, sunken chamber certainly well septum piece face in the second preceding chamber one side in the first preceding chamber is sunken to be formed.

2. An in-ear headphone as claimed in claim 1, wherein the acoustic structure of the front acoustic cavity, the recessed cavity and the vibrating diaphragm has a resonant frequency of 5.0kHz or less and 7.5kHz or less.

3. The in-ear headphone of claim 1, wherein the sound outlet is in communication with the first front cavity;

4. The in-ear headphone of claim 1, wherein the housing further comprises an upper shell and a lower shell disposed on opposite sides of the septum, the upper shell housing a sound generating unit forming the first front cavity and the lower shell housing a sound generating unit forming the second front cavity;

the middle partition piece comprises a partition plate and a hollow outer frame, the partition plate and the hollow outer frame are respectively arranged at intervals relative to the sound generating unit, the outer peripheral side of the outer frame is respectively connected with the upper shell and the lower shell, the outer peripheral side of the partition plate is connected with the outer frame, and the partition plate forms the sunken cavity.

5. An in-ear headphone as claimed in claim 4, wherein the diaphragm protrudes towards the first front cavity to form the recessed cavity.

6. An in-ear headphone according to any one of claims 1 to 5, wherein a diaphragm vibration direction of the sound emitting unit is perpendicular to a sound emitting direction of the sound emitting hole.

7. An in-ear headphone as claimed in any one of claims 1 to 5, characterized in that one of the two sound-emitting units is a bass sound-emitting unit and the other is a bass sound-emitting unit or a treble sound-emitting unit.

8. The in-ear headphone of claim 7, wherein the sound-generating unit forming the first front cavity with the septum is a high-pitch sound-generating unit, and the sound-generating unit forming the second front cavity with the septum is a low-pitch sound-generating unit.

9. An in-ear headphone according to claim 1, wherein the housing further defines a pressure equalizing hole communicating with the first front cavity and/or the second front cavity, and the pressure equalizing hole communicates with the headphone rear cavity.