Sound generating device and wearable device

Abstract

The present invention discloses a sound generating device, which includes: a housing with a cavity formed therein; a double-sided sound generating unit disposed in the cavity. The double-sided sound generating unit includes a first diaphragm assembly and a second diaphragm assembly arranged back to back, and the first diaphragm assembly and the second diaphragm assembly vibrate in the same direction. The first diaphragm assembly and the inner wall of the housing cooperate to define a first front sound cavity, and the second diaphragm assembly and the inner wall of the housing cooperate to define a second front sound cavity. Sound holes communicating with the first front sound cavity and the second front sound cavity are provided on the housing; wherein, the volume V1 of the first front sound cavity and the volume V2 of the second front sound cavity satisfy the relationship: 0.9 < V1 / V2 < 1.1. According to the sound generating device of the present invention, by defining the volume V1 of the first front sound cavity and the volume V2 of the second front sound cavity to be 0.9 < V1 / V2 < 1.1, it is possible to broaden the effective sound cancellation frequency band and better improve the effect of reducing far-field sound leakage.

Description

Technical Field

[0001] The present invention relates to the technical field of electroacoustics, and particularly relates to a sound generating device and a wearable device. Background Art

[0002] External audio devices are now widely used in wearable devices such as AR, VR, and headphones. With the continuous upgrading of user requirements, the requirements for privacy protection of external audio devices are getting higher and higher.

[0003] There are serious sound leakage problems in the design of existing external audio devices, and it is difficult to meet the requirements of protecting user privacy. Although there are anti-leakage designs using the principle of acoustic dipoles in existing products, the effective sound cancellation frequency band range that can be achieved by existing products is limited, and the effect of reducing far-field sound leakage is poor, far from meeting the requirements of protecting user privacy. Summary of the Invention

[0004] The present invention aims to at least solve one of the technical problems existing in the prior art. For this purpose, the present invention provides a sound generating device, which has the advantages of broadening the sound cancellation frequency band and achieving better far-field sound leakage reduction effect.

[0005] The present invention also provides a wearable device with the above-mentioned sound generating device.

[0006] The sound generating device according to the first aspect embodiment of the present invention includes: a housing, a cavity is provided inside the housing; a double-sided sound generating unit, the double-sided sound generating unit is provided in the cavity, the double-sided sound generating unit includes a first diaphragm assembly and a second diaphragm assembly arranged back to back, the first diaphragm assembly and the second diaphragm assembly vibrate in the same direction, the first diaphragm assembly and the inner wall of the housing cooperate to define a first front sound cavity, the second diaphragm assembly and the inner wall of the housing cooperate to define a second front sound cavity, and sound holes communicating with the first front sound cavity and the second front sound cavity are provided on the housing; wherein, the volume V1 of the first front sound cavity and the volume V2 of the second front sound cavity satisfy the relationship: 0.9 < V1 / V2 < 1.1.

[0007] The sound generating device according to the embodiment of the first aspect of the present invention, the double-sided sound generating unit and the inner wall of the housing cooperate to define a first front sound cavity and a second front sound cavity, and sound holes are provided on the housing and are respectively communicated with the first front sound cavity and the second front sound cavity. Among them, the ratio of the volume V1 of the first front sound cavity to the volume V2 of the second front sound cavity satisfies: 0.9 < V1 / V2 < 1.1. With such a setting, the resonance frequency difference between the first front sound cavity and the second front sound cavity of the sound generating device is limited within an appropriate range, and it is possible to avoid the sudden change of the phase difference of the sound waves radiated from different sound holes when the sound frequency is near the resonance frequencies of the first front sound cavity and the second front sound cavity. Thus, the effective sound cancellation frequency band range is broadened, and a better effect of reducing far-field sound leakage is achieved, meeting the needs of user privacy protection.

[0008] According to some embodiments of the present invention, the sound holes include a first sound hole communicated with the first front sound cavity and a second sound hole communicated with the second front sound cavity, and the sound waves emitted from the first sound hole and the sound waves emitted from the second sound hole are opposite in phase and form a dipole effect in the far field.

[0009] In some embodiments of the present invention, the sound generating device further includes: a first sound duct, the first sound duct communicating the first front sound cavity and the first sound hole; a second sound duct, the second sound duct communicating the second front sound cavity and the second sound hole; wherein, the length of the first sound duct is L1, the average cross-sectional area of the first sound duct is S1, the length of the second sound duct is L2, the average cross-sectional area of the second sound duct is S2, the density of air is ρ, the acoustic mass Ma1 of the first front sound cavity = ρ*L1 / S1, the acoustic mass Ma2 of the second front sound cavity = ρ*L2 / S2, 0.9 < Ma1 / Ma2 < 1.1.

[0010] According to some embodiments of the present invention, four sound holes are provided on the housing, two of the sound holes are respectively communicated with the first front sound cavity, and the other two sound holes are respectively communicated with the second front sound cavity. The sound waves emitted from the two sound holes communicated with the first front sound cavity and the sound waves emitted from the two sound holes communicated with the second front sound cavity are opposite in phase and form a quadrupole effect in the far field.

[0011] In some embodiments of the present invention, the vertical projections of the four sound holes on the horizontal plane form four projection sound holes distributed in an array. The center position distance between two projection sound holes with the same sound emission phase is a first distance, and the center position distance between two projection sound holes with opposite sound emission phases is a second distance, and the first distance is greater than the second distance.

[0012] In some embodiments of the present invention, the center positions of the four projection sound holes are connected end to end in sequence to form a square, and the two projection sound holes located at the diagonal positions have the same sound emission phase.

[0013] In some embodiments of the present invention, the two sound holes communicating with the first front sound cavity are respectively the third sound hole and the fourth sound hole, and the two sound holes communicating with the second front sound cavity are respectively the fifth sound hole and the sixth sound hole; the sound generating device further includes: a third sound pipe and a fourth sound pipe, the third sound pipe communicates the first front sound cavity and the third sound hole, and the fourth sound pipe communicates the first front sound cavity and the fourth sound hole; a fifth sound pipe and a sixth sound pipe, the fifth sound pipe communicates the second front sound cavity and the fifth sound hole, and the sixth sound pipe communicates the second front sound cavity and the sixth sound hole; wherein, the length of the third sound pipe is L3, the average cross-sectional area of the third sound pipe is S3, the length of the fourth sound pipe is L4, the average cross-sectional area of the fourth sound pipe is S4, the length of the fifth sound pipe is L5, the average cross-sectional area of the fifth sound pipe is S5, the length of the sixth sound pipe is L6, the average cross-sectional area of the sixth sound pipe is S6, the density of air is ρ, the acoustic mass of the third sound pipe is Ma3 = ρ * L3 / S3, the acoustic mass of the fourth sound pipe is Ma4 = ρ * L4 / S4, the acoustic mass of the fifth sound pipe is Ma5 = ρ * L5 / S5, the acoustic mass of the sixth sound pipe is Ma6 = ρ * L6 / S6;

[0014] The total acoustic mass of the first front sound cavity is M1 = Ma3 * Ma4 / (Ma3 + Ma4), the total acoustic mass of the second front sound cavity is M2 = Ma5 * Ma6 / (Ma5 + Ma6), and 0.9 < M1 / M2 < 1.1.

[0015] According to some embodiments of the present invention, the double-sided sound generating unit includes: a magnetic circuit system provided with a magnetic gap; a first vibration system and a second vibration system, the first vibration system and the second vibration system are arranged on opposite sides of the magnetic circuit system, the first vibration system includes the first diaphragm assembly and the first voice coil, the second vibration system includes the second diaphragm assembly and the second voice coil, and the first voice coil and the second voice coil are located on opposite sides of the magnetic circuit system and are both inserted into the magnetic gap.

[0016] According to some embodiments of the present invention, the dual-sided sound generating unit includes: a first sound generating element, the first sound generating element includes a first magnetic circuit system and a first vibration system, the first magnetic circuit system is provided with a first magnetic gap, the first vibration system includes the first diaphragm assembly and a first voice coil, and the first voice coil is inserted into the first magnetic gap; a second sound generating element, the second sound generating element is arranged opposite to the first sound generating element, the second sound generating element includes a second magnetic circuit system and a second vibration system, the second magnetic circuit system is arranged opposite to the first magnetic circuit system and is provided with a second magnetic gap, and the second vibration system includes the second diaphragm assembly and a second voice coil, and the second voice coil is inserted into the second magnetic gap.

[0017] The wearable device according to the second aspect embodiment of the present invention includes the sound generating device according to the above first aspect embodiment of the present invention.

[0018] The wearable device according to the second aspect embodiment of the present invention, by providing the above-mentioned sound generating device, that is, the housing of the sound generating device and the dual-sided sound generating unit define a first front sound cavity and a second front sound cavity, and sound holes respectively communicating with the first front sound cavity and the second front sound cavity are provided on the housing, and the volume V1 of the first front sound cavity and the volume V2 of the second front sound cavity satisfy the relational expression: 0.9 < V1 / V2 < 1.1, which broadens the effective sound cancellation frequency band of the sound generating device, thereby greatly improving the effect of the wearable device in reducing far-field sound leakage and fully meeting the needs of users for privacy protection.

[0019] The additional aspects and advantages of the present invention will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present invention. Description of the Drawings

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0021] Figure 1 It is an exploded view of the structure of the sound generating device according to an embodiment of the present invention;

[0022] Figure 2 It is a schematic diagram of the structure of the sound generating device according to an embodiment of the present invention;

[0023] Figure 3 For Figure 2 It is a schematic diagram of the structure of the sound generating device according to an embodiment of the present invention from another angle;

[0024] Figure 4For Figure 2 A cross-sectional view of the sound generating device according to an embodiment of the present invention along the first front sound cavity as shown;

[0025] Figure 5 For Figure 2 A cross-sectional view of the sound generating device according to an embodiment of the present invention along the second front sound cavity as shown;

[0026] Figure 6 A top view of the sound generating device according to another embodiment of the present invention;

[0027] Figure 7 For Figure 6 A schematic structural view of the sound generating device according to another embodiment of the present invention as shown;

[0028] Figure 8 For Figure 6 A schematic structural view of the sound generating device according to another embodiment of the present invention from another angle as shown;

[0029] Figure 9 For Figure 6 A cross-sectional view of the sound generating device according to another embodiment of the present invention along the first front sound cavity as shown;

[0030] Figure 10 For Figure 6 A cross-sectional view of the sound generating device according to another embodiment of the present invention along the second front sound cavity as shown.

[0031] Reference numerals:

[0032] Sound generating device 100,

[0033] Housing 1, first housing 11, second housing 12, first sound hole 21, second sound hole 22, third sound hole 23, fourth sound hole 24, fifth sound hole 25, sixth sound hole 26, first sound duct 41, second sound duct 42, third sound duct 43, fourth sound duct 44, fifth sound duct 45, sixth sound duct 46, first front sound cavity 31, second front sound cavity 32,

[0034] Double-sided sound generating unit 4.

[0035] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Detailed implementation manners

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0037] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present invention, then such directional indications are only used to explain the relative positional relationship, movement conditions, etc. between components in a certain specific posture (as shown in the accompanying drawings). If this specific posture changes, then the directional indications will also change accordingly.

[0038] In addition, if descriptions such as "first", "second", etc. are involved in the embodiments of the present invention, then such descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those skilled in the art can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0039] In the present invention, the descriptions of orientations such as "up", "down", "front", "back", "left", "right", etc. are based on Figure 1 the orientation shown, and are only used to explain the relative positional relationship between components in Figure 1 the posture shown. If this specific posture changes, then the directional indications will also change accordingly.

[0040] Next, refer to Figures 1 - 10 to describe in detail the sound generating device 100 according to the embodiment of the first aspect of the present invention. Among them, the sound generating device 100 may be a speaker.

[0041] As Figures 1 - 10 shown, the sound generating device 100 according to the embodiment of the first aspect of the present invention includes: a housing 1, a cavity is provided inside the housing 1; a double-sided sound generating unit 4, the double-sided sound generating unit 4 is provided in the cavity, the double-sided sound generating unit 4 includes a first diaphragm assembly and a second diaphragm assembly arranged back to back, the first diaphragm assembly and the second diaphragm assembly vibrate in the same direction, the first diaphragm assembly and the inner wall of the housing 1 cooperate to define a first front sound cavity 31, the second diaphragm assembly and the inner wall of the housing 1 cooperate to define a second front sound cavity 32, and sound holes are provided on the housing 1 and communicate with the first front sound cavity 31 and the second front sound cavity 32 respectively; wherein, the volume V1 of the first front sound cavity 31 and the volume V2 of the second front sound cavity 32 satisfy the relational expression: 0.9 < V1 / V2 < 1.1.

[0042] Specifically, as Figures 1 - 10In the illustrated embodiment, the housing 1 of the sound generating device 100 includes a first housing 11 and a second housing 12. The double-sided sound generating unit 4 is fixed to the second housing 12, and the first housing 11 covers the second housing 12 to form a cavity. The double-sided sound generating unit 4 includes a first diaphragm assembly and a second diaphragm assembly arranged back to back, and the first diaphragm assembly and the second diaphragm assembly vibrate in the same direction. On the two opposite sides of the double-sided sound generating unit 4 in the thickness direction, that is, the side where the first diaphragm assembly and the second diaphragm assembly are located, they respectively enclose with the first housing 11 and the second housing 12 to form mutually isolated first front sound cavities 31 and second front sound cavities 32. Among them, the first diaphragm assembly and the inner wall of the housing 1 cooperate to define the first front sound cavity 31, and the second diaphragm assembly and the inner wall of the housing 1 cooperate to define the second front sound cavity 32. The side wall of the double-sided sound generating unit 4 and the first housing 11 and the second housing 12 cooperate to enclose a closed rear sound cavity 33. Sound holes are provided on the housing 1 and are respectively communicated with the first front sound cavity 31 and the second front sound cavity 32. Among them, the sizes of the volume V1 of the first front sound cavity 31 and the volume V2 of the second front sound cavity 32 satisfy the relationship: 0.9 < V1 / V2 < 1.1.

[0043] In the embodiment provided by the present invention, the purpose of limiting the sizes of the volume V1 of the first front sound cavity 31 and the volume V2 of the second front sound cavity 32 to satisfy the relationship: 0.9 < V1 / V2 < 1.1 is to ensure that the resonance frequencies of the first front sound cavity 31 and the second front sound cavity 32 are similar, or in other words, to ensure that the difference in the resonance frequencies of the first front sound cavity 31 and the second front sound cavity 32 is small enough. Specifically, refer to the following formula:

[0044]

[0045] Among them, Ma is the acoustic mass of the cavity, and Ca is the acoustic capacitance of the cavity. Further, refer to the following formula:

[0046]

[0047] Among them, V is the volume of the front sound cavity, l is the length of the sound pipe, S is the cross-sectional area of the sound pipe, ρ is the air density, and c is the speed of sound in air.

[0048] According to the above formula, it can be seen that the resonance frequencies of the first front sound cavity 31 and the second front sound cavity 32 are related to the volume of the front sound cavity, the length and cross-sectional area of the sound pipe. Among them, the volume of the front sound cavity is the decisive variable affecting the resonance frequencies of the first front sound cavity 31 and the second front sound cavity 32. Therefore, in the embodiment provided by the present invention, the size relationship between the volume V1 of the first front sound cavity 31 and the volume V2 of the second front sound cavity 32 is limited to satisfy the relationship: 0.9 < V1 / V2 < 1.1, so as to achieve the purpose of limiting the difference in the resonance frequencies of the first front sound cavity 31 and the second front sound cavity 32 to be small enough, and making the resonance frequencies of the first front sound cavity 31 and the second front sound cavity 32 as close as possible.

[0049] In the embodiment of the present invention as shown in Figures 1 - 10 , the sound holes opened in the housing are respectively connected to the first front sound cavity 31 and the second front sound cavity 32, and the first diaphragm assembly and the second diaphragm assembly vibrate in the same direction. As a result, the sound waves radiated from the sound holes connected to the first front sound cavity 31 and the sound holes connected to the second front sound cavity 32 have opposite phases. Furthermore, the sound waves with opposite phases cancel each other out, which can reduce the sound leakage volume in the far field of the sound generating device 100. Since in the embodiment provided by the present invention, the volume ratio of the first front sound cavity 31 to the second front sound cavity 32 is limited to 0.9 - 1.1, the common frequencies of the first front sound cavity 31 and the second front sound cavity 32 are similar. Therefore, when the frequency of the sound waves radiated from the sound holes is near the common frequency of the first front sound cavity 31 and the second front sound cavity 32, the sound waves with opposite phases can still maintain a relatively stable phase difference. Thus, the effect of broadening the effective sound cancellation frequency band of the sound generating device 100 can be achieved, so that the sound generating device 100 provided by the present invention has a better effect of reducing the far field leakage volume compared with existing products.

[0050] For the sound generating device 100 according to the first aspect embodiment of the present invention, the double-sided sound generating unit 4 and the inner wall of the housing 1 cooperate to define the first front sound cavity 31 and the second front sound cavity 32. The housing is provided with sound holes respectively connected to the first front sound cavity 31 and the second front sound cavity 32. Among them, the ratio of the volume V1 of the first front sound cavity 31 to the volume V2 of the second front sound cavity 32 satisfies: 0.9 < V1 / V2 < 1.1. With such a setting, the resonance frequency difference between the first front sound cavity 31 and the second front sound cavity 32 of the sound generating device 100 is limited within an appropriate range, which can avoid the sudden change of the phase difference of the sound waves radiated from different sound holes when the sound frequency is near the resonance frequencies of the first front sound cavity 31 and the second front sound cavity 32. Thus, the range of the effective sound cancellation frequency band is broadened, and a better effect of reducing the far field leakage sound is achieved, meeting the needs of user privacy protection.

[0051] In Figure 1In the illustrated embodiment, the sound holes formed in the housing 1 are formed by opening through holes in the first housing 11 and the second housing 12. Alternatively, in other embodiments, the sound holes formed in the housing 1 can also be formed by the cooperation of the first housing 11 and the second housing 12, such as a groove with an open end facing the second housing 12 on the side wall of the first housing 11, and then the corresponding sound holes are formed by snapping the first housing 11 and the second housing 12 together. Specifically, it can be designed according to the actual situation and is not limited herein. In addition, it should be emphasized that in the embodiment shown in the present invention, the first front sound cavity 31, the second front sound cavity 32, and the rear sound cavity 33 are enclosed by the housing 1 of the sound generating device 100 and the double-sided sound generating unit 4. In other embodiments, the double-sided sound generating unit 4 can also cooperate with the corresponding terminal housing to form the corresponding first front sound cavity 31, second front sound cavity 32, and rear sound cavity 33. That is, the embodiment shown in the present invention is only one implementation manner of the present invention, and other deformed structures adopting similar technical features to the present invention are also within the protection scope of the present invention.

[0052] In some embodiments of the present invention, such as Figures 2 - 5 shown, the sound holes formed in the housing 1 include a first sound hole 21 communicating with the first sound cavity 31 and a second sound hole 22 communicating with the second front sound cavity 32. The sound waves emitted from the first sound hole 21 and the second sound hole 22 are opposite in phase and form a dipole effect in the far field. Such as Figure 2 and Figure 3 shown in the embodiment, the first sound hole 21 and the second sound hole 22 are respectively formed on the opposite sides of the first housing 11 and the second housing 12. It should be emphasized that the opening positions of the first sound hole 21 and the second sound hole 22 are not limited to those shown in the drawings, and other opening position selections that can satisfy the dipole effect formed by the sound waves radiated from the first sound hole 21 and the second sound hole 22 to the far field are within the protection scope of the present invention and are not limited herein. In Figures 2 - 5 the shown embodiment, the housing 1 is provided with two sound holes, forming a dipole effect in the far field, which can achieve the effect of reducing the sound leakage amount in the far field. The number of sound holes required to form the dipole effect is relatively small, and the manufacturing process is more convenient.

[0053] Furthermore, in some embodiments of the present invention, such as Figure 4 and Figure 5 shown, the sound generating device 100 further includes a first sound duct 41 and a second sound duct 42. The first sound duct 41 communicates the first front sound cavity 31 and the first sound hole 21, and the second sound duct 42 communicates the second front sound cavity 32 and the second sound hole 22. That is, the sound waves generated by the first diaphragm assembly are transmitted to the first sound hole 21 via the first front sound cavity 31 and the first sound duct 41, and then radiated to the outside of the sound generating device 100. The sound waves generated by the second diaphragm assembly are transmitted to the second sound hole 22 via the second front sound cavity 32 and the second sound duct 42, and then radiated to the outside of the sound generating device 100. Among them, such asFigure 4 and Figure 5 As shown, define the length of the first sound pipe 41 as L1, the average cross-sectional area of the first sound pipe 41 as S1, the length of the second sound pipe 42 as L2, the average cross-sectional area of the second sound pipe 42 as S2, and the air density as ρ. Thus, according to the aforementioned formula, the acoustic mass Ma1 of the first front sound cavity 31 = ρ * L1 / S1, and the acoustic mass Ma2 of the second front sound cavity 32 = ρ * L2 / S2. It is defined that the magnitude relationship between Ma1 and Ma2 satisfies: 0.9 < Ma1 / Ma2 < 1.1. By changing the lengths and average cross-sectional areas of the first sound pipe 41 and the second sound pipe 42, the ratio range of the acoustic masses of the first front sound cavity 31 and the second front sound cavity 32 is adjusted to: 0.9 - 1.1. Thus, on the basis of defining the volume ratio of the first front sound cavity 31 and the second front sound cavity 32, further defining the acoustic mass ratio of the first front sound cavity 31 and the second front sound cavity 32 can further ensure that the resonance frequencies of the first front sound cavity 31 and the second front sound cavity 32 are close. Therefore, the effective sound cancellation frequency band can be broadened, enabling the sound generating device 100 to reduce the far-field sound leakage amount within a larger medium and high frequency range, thereby effectively protecting the privacy of the user. It should be emphasized that the average cross-sectional area S of the sound pipe shown in this embodiment is an idealized inference value. That is, along the sound wave radiation direction, the cross-sectional area of the sound pipe is usually gradually changing or in other irregular forms. Thus, assuming that along the sound wave radiation direction, the cross-sectional area of the sound pipe is subdivided into several small units, and then the average cross-sectional area S of the sound pipe can be calculated through the sum of the inner wall areas of the sound pipe of each unit and the number of the subdivided small units. It can be known that the more the number of subdivisions of the small units, the closer the value of the average cross-sectional area S is to the actual value. In addition, if the sound pipe is in a regular shape, the corresponding cross-sectional area can be directly measured for calculation.

[0054] In some embodiments of the present invention, four sound holes are opened on the housing 1. Among them, two sound holes are respectively connected to the first front sound cavity 31, and the other two sound holes are respectively connected to the second front sound cavity 32. The sound waves emitted from the two sound holes connected to the first front sound cavity 31 and the sound waves emitted from the two sound holes connected to the second front sound cavity 32 are opposite in phase and form a quadrupole effect in the far field.

[0055] Specifically, such as Figures 6 - 10In the illustrated embodiment, the four sound holes are respectively the third sound hole 23 and the fourth sound hole 24 that communicate with the first front sound cavity 31, and the fifth sound hole 25 and the sixth sound hole 26 that communicate with the second front sound cavity. The sound waves emitted by the third sound hole 23 and the fourth sound hole 24 are opposite in phase to the sound waves emitted by the fifth sound hole 25 and the sixth sound hole 26. Thus, a quadrupole effect can be formed in the far field of the sound generating device 100. Compared with the dipole anti-sound leakage design in existing products, the quadrupole effect can greatly reduce the far-field sound leakage amount, further improve the user experience of the user, and meet the user's demand for privacy protection.

[0056] According to some embodiments of the present invention, the vertical projections of the four sound holes opened on the housing 1 on the horizontal plane can form four projection sound holes distributed in an array. The center position spacing between two projection sound holes with the same sound emission phase polarity is the first spacing, and the center position spacing between two projection sound holes with opposite sound emission phase polarities is the second spacing, and the first spacing is greater than the second spacing.

[0057] Specifically, as Figure 6 shown, the vertical projections of the third sound hole 23, the fourth sound hole 24, the fifth sound hole 25 and the sixth sound hole 26 on the horizontal plane are distributed in an array. Among them, the third sound hole 23 and the fourth sound hole 24 have the same phase, and the fifth sound hole 25 and the sixth sound hole 26 have the same phase and are opposite in phase polarity to the third sound hole 23 and the fourth sound hole 24. As Figure 6 shown, the phase polarities between adjacent two sound holes are different, and the center position spacing between two sound holes with the same phase polarity is greater than the center position spacing between any two sound holes with different phase polarities. Thus, the four sound holes form four radiation sources, and then jointly form a quadrupole effect, which can significantly reduce the far-field sound leakage amount and improve the privacy of use of the sound generating device 100.

[0058] In some embodiments of the present invention, the center positions of the four projection sound holes are connected end to end in sequence to form a square, and the sound emission phase polarities of the two projection sound holes located at the diagonal positions are the same. Thus, when the first diaphragm assembly 21 and the second diaphragm assembly 22 vibrate in the same direction, the phase difference between every two of the four sound holes of the sound generating device 100 is 180°, jointly constituting a coplanar quadrupole, and thus the far-field sound leakage amount can be significantly reduced.

[0059] In some embodiments of the present invention, as Figures 7 - 10As shown, the third sound hole 23 and the fourth sound hole 24 opened on the housing 1 of the sound generating device 100 are communicated with the first front sound cavity 31, and the fifth sound hole 25 and the sixth sound hole 26 are communicated with the second front sound cavity 32. The sound generating device 100 further includes a third sound pipe 43, a fourth sound pipe 44, a fifth sound pipe 45 and a sixth sound pipe 46. Among them, the third sound pipe 43 communicates the first front sound cavity 31 and the third sound hole 23, the fourth sound pipe 44 communicates the first front sound cavity 31 and the fourth sound hole 24, the fifth sound pipe 45 communicates the second front sound cavity 32 and the fifth sound hole 25, and the sixth sound pipe 46 communicates the second front sound cavity 32 and the sixth sound hole 26. As Figures 7 - 10 As shown, define the length of the third sound pipe 43 as L3, the average cross-sectional area of the third sound pipe 43 as S3, the length of the fourth sound pipe 44 as L4, the average cross-sectional area of the fourth sound pipe 44 as S4, the length of the fifth sound pipe 45 as L5, the average cross-sectional area of the fifth sound pipe 45 as S5, the length of the sixth sound pipe 46 as L6, and the average cross-sectional area of the sixth sound pipe 46 as S6. The density of air is ρ. The acoustic mass of the third sound pipe 43 is Ma3 = ρ * L3 / S3, the acoustic mass of the fourth sound pipe 44 is Ma4 = ρ * L4 / S4, the acoustic mass of the fifth sound pipe 45 is Ma5 = ρ * L5 / S5, and the acoustic mass of the sixth sound pipe 46 is Ma6 = ρ * L6 / S6. Referring to the foregoing formula and the above definitions, it can be known that the total acoustic mass of the first front sound cavity 31 is M1 = Ma3 * Ma4 / (Ma3 + Ma4), and the total acoustic mass of the second front sound cavity 32 is M2 = Ma5 * Ma6 / (Ma5 + Ma6). It is specified that the relationship between the total acoustic masses of the first front sound cavity 31 and the second front sound cavity 32 satisfies: 0.9 < M1 / M2 < 1.1. By limiting the lengths and average cross-sectional areas of the foregoing third sound pipe 43, fourth sound pipe 44, fifth sound pipe 45 and sixth sound pipe 46, the ratio range of the total acoustic masses of the first front sound cavity 31 and the second front sound cavity 32 is further limited. On the basis that the sound waves emitted from the foregoing four sound holes can form a quadrupole effect, the resonance frequencies of the first front sound cavity 31 and the second front sound cavity 32 are further ensured to be similar. Thus, the effective sound cancellation frequency band can be broadened, so that the sound generating device 100 can reduce the far-field sound leakage amount within a larger medium and high frequency range, thereby effectively protecting the privacy of the user.

[0060] In some embodiments of the present invention, the double-sided sound generating unit 4 includes a magnetic circuit system provided with a magnetic gap; a first vibration system and a second vibration system. The first vibration system and the second vibration system are disposed on opposite sides of the magnetic circuit system. The first vibration system includes a first diaphragm assembly and a first voice coil, and the second vibration system includes a second diaphragm assembly and a second voice coil. A first front sound cavity 31 is defined between the first diaphragm assembly and the inner wall of the housing 1, and a second front sound cavity 32 is defined between the second diaphragm assembly and the inner wall of the housing 1. The first voice coil and the second voice coil are located on opposite sides of the magnetic circuit system and are both inserted into the magnetic gap. When the double-sided sound generating unit 4 operates, the first voice coil and the second voice coil are energized, and under the action of the magnetic field generated by the magnetic circuit system, the first diaphragm and the second diaphragm are driven to vibrate reciprocally. The vibration directions of the first vibration system and the second vibration system are the same, that is, the vibration directions of the first diaphragm and the second diaphragm are the same. Thus, it is ensured that the sound waves radiated from the two sound holes communicating with the first front sound cavity 31 corresponding to the first diaphragm and the two sound holes communicating with the second front sound cavity 32 corresponding to the second diaphragm have opposite phase polarities, thereby forming a quadrupole effect in the far field and reducing the sound leakage amount. By providing that the first vibration system and the second vibration system share the same magnetic circuit system, the thickness of the double-sided sound generating unit 4 can be reduced, which is beneficial to the thin-type design of the sound generating device 100 and reduces the occupation of the internal space of the terminal.

[0061] Further, in some embodiments of the present invention, the double-sided sound generating unit 4 includes: a first sound generating monomer, the first sound generating monomer includes a first magnetic circuit system and a first vibration system. The first magnetic circuit system is provided with a first magnetic gap, the first vibration system includes a first diaphragm assembly and a first voice coil, and the first voice coil is inserted into the first magnetic gap. A first front sound cavity 31 is defined between the first diaphragm assembly and the inner wall of the housing 1; a second sound generating monomer, the second sound generating monomer is disposed back-to-back with the first sound generating monomer. The second sound generating monomer includes a second magnetic circuit system and a second vibration system. The second magnetic circuit system is disposed back-to-back with the first magnetic circuit system and is provided with a second magnetic gap. The second vibration system includes a second diaphragm assembly and a second voice coil, and the second voice coil is inserted into the second magnetic gap. A second front sound cavity 32 is defined between the second diaphragm assembly and the inner wall of the housing. That is, in addition to the design of using two vibration systems to share the same magnetic circuit system, the double-sided sound generating unit 4 can also be formed by combining two single-sided sound generating monomers disposed back-to-back. During the operation of the double-sided sound generating unit 4, the sound waves generated by the first sound generating monomer and the second sound generating monomer have opposite phase polarities. Thus, it is ensured that the sound waves radiated from the two sound holes communicating with the first front sound cavity 31 corresponding to the first sound generating monomer and the two sound holes communicating with the second front sound cavity 32 corresponding to the second sound generating monomer have opposite phase polarities, thereby forming a quadrupole effect in the far field and reducing the sound leakage amount. With such a setting, that is, forming the double-sided sound generating unit 4 by disposing two single-sided sound generating monomers back-to-back, the preparation process of the double-sided sound generating unit 4 can be made simpler and more convenient.

[0062] The wearable device according to the embodiment of the second aspect of the present invention includes the sound generating device 100 according to the embodiment of the first aspect of the present invention above. The wearable device according to the embodiment of the second aspect of the present invention may include, but is not limited to, devices such as AR, VR, or headphones.

[0063] The wearable device according to the embodiment of the second aspect of the present invention, by providing the above-mentioned sound generating device 100, that is, the housing 1 of the sound generating device 100 and the double-sided sound generating unit 4 define a first front sound cavity 31 and a second front sound cavity 32, and sound holes are provided on the housing 1 that are respectively connected to the first front sound cavity 31 and the second front sound cavity 32. The volume V1 of the first front sound cavity 31 and the volume V2 of the second front sound cavity 32 satisfy the relationship: 0.9 < V1 / V2 < 1.1, which broadens the effective sound cancellation frequency band of the sound generating device 100, thereby greatly improving the effect of reducing sound leakage of the wearable device and fully meeting the needs of users for privacy protection.

[0064] It should be noted that the above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structural transformation made by using the description and drawings of the present invention under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A sound-generating device, characterized in that: include: a housing, wherein a cavity is provided in the housing; A double-sided sound-emitting unit, the double-sided sound-emitting unit being arranged in the cavity, the double-sided sound-emitting unit comprising a first diaphragm assembly and a second diaphragm assembly arranged back to back, the first diaphragm assembly and the second diaphragm assembly vibrating in the same direction, the first diaphragm assembly cooperating with the inner wall of the shell to define a first front sound cavity, the second diaphragm assembly cooperating with the inner wall of the shell to define a second front sound cavity, the shell being provided with sound holes respectively communicating with the first front sound cavity and the second front sound cavity; The volume V1 of the first front acoustic cavity and the volume V2 of the second front acoustic cavity satisfy the relationship: 0.9<V1 / V2<1.1; The housing is provided with four sound holes, two of which are respectively connected to the first front sound cavity, and the other two are respectively connected to the second front sound cavity. The sound waves emitted by the two sound holes connected to the first front sound cavity are in opposite phases to the sound waves emitted by the two sound holes connected to the second front sound cavity, and form a quadrupole effect in the far field. The two sound holes communicating with the first front sound cavity are the third sound hole and the fourth sound hole, and the two sound holes communicating with the second front sound cavity are the fifth sound hole and the sixth sound hole. The sound-generating device further comprises: a third acoustic pipe and a fourth acoustic pipe, wherein the third acoustic pipe is connected to the first front acoustic cavity and the third acoustic hole, and the fourth acoustic pipe is connected to the first front acoustic cavity and the fourth acoustic hole; a fifth sound pipe and a sixth sound pipe, wherein the fifth sound pipe is connected to the second front sound cavity and the fifth sound hole, and the sixth sound pipe is connected to the second front sound cavity and the sixth sound hole; Wherein, the length of the third acoustic pipe is L3, the average cross-sectional area of the third acoustic pipe is S3, the length of the fourth acoustic pipe is L4, the average cross-sectional area of the fourth acoustic pipe is S4, the length of the fifth acoustic pipe is L5, the average cross-sectional area of the fifth acoustic pipe is S5, the length of the sixth acoustic pipe is L6, the average cross-sectional area of the sixth acoustic pipe is S6, the density of air is ρ, the sound mass of the third acoustic pipe is Ma3 = ρ*L3 / S3, the sound mass of the fourth acoustic pipe is Ma4 = ρ*L4 / S4, the sound mass of the fifth acoustic pipe is Ma5 = ρ*L5 / S5, and the sound mass of the sixth acoustic pipe is Ma6 = ρ*L6 / S6; The total sound mass of the first front acoustic cavity is M1 = Ma3*Ma4 / (Ma3+Ma4), and the total sound mass of the second front acoustic cavity is M2 = Ma5*Ma6 / (Ma5+Ma6), 0.9<M1 / M2<1.

1.

2. The sound-generating device according to claim 1, wherein: The sound hole includes a first sound hole connected to the first front sound cavity and a second sound hole connected to the second front sound cavity. The sound waves emitted by the first sound hole are in opposite phases to the sound waves emitted by the second sound hole and form a dipole effect in the far field.

3. The sound-generating device according to claim 2, characterized in that: The sound-generating device further comprises: a first acoustic pipe, the first acoustic pipe communicating with the first front acoustic cavity and the first acoustic hole; a second acoustic pipe, the second acoustic pipe communicating with the second front acoustic cavity and the second acoustic hole; Among them, the length of the first acoustic duct is L1, the average cross-sectional area of the first acoustic duct is S1, the length of the second acoustic duct is L2, the average cross-sectional area of the second acoustic duct is S2, the density of air is ρ, the sound mass of the first front acoustic cavity Ma1 = ρ*L1 / S1, the sound mass of the second front acoustic cavity Ma2 = ρ*L2 / S2, 0.9<Ma1 / Ma2<1.

1.

4. The sound-generating device according to claim 1, wherein: The vertical projections of the four sound holes on the horizontal plane form four projected sound holes distributed in an array, the center positions of two projected sound holes with the same sound output phase are spaced apart by a first spacing, and the center positions of two projected sound holes with opposite sound output phases are spaced apart by a second spacing, and the first spacing is greater than the second spacing.

5. The sound-generating device according to claim 4, characterized in that: The centers of the four projected sound holes are connected end to end in sequence to form a square, and the sound output phases of the two projected sound holes located at diagonal positions are the same.

6. The sound-generating device according to any one of claims 1 to 5, characterized in that: The double-sided sound emitting unit comprises: A magnetic circuit system, wherein the magnetic circuit system is provided with a magnetic gap; A first vibration system and a second vibration system, wherein the first vibration system and the second vibration system are arranged on opposite sides of the magnetic circuit system, the first vibration system includes the first diaphragm assembly and the first voice coil, and the second vibration system includes the second diaphragm assembly and the second voice coil, the first voice coil and the second voice coil are located on opposite sides of the magnetic circuit system and are both inserted into the magnetic gap.

7. The sound-generating device according to any one of claims 1 to 5, characterized in that: The double-sided sound emitting unit comprises: a first sound-emitting unit, the first sound-emitting unit including a first magnetic circuit system and a first vibration system, the first magnetic circuit system being provided with a first magnetic gap, the first vibration system including the first diaphragm assembly and a first voice coil, the first voice coil being inserted into the first magnetic gap; A second sound-emitting unit, the second sound-emitting unit is arranged back to back with the first sound-emitting unit, the second sound-emitting unit includes a second magnetic circuit system and a second vibration system, the second magnetic circuit system is arranged back to back with the first magnetic circuit system and is provided with a second magnetic gap, the second vibration system includes the second diaphragm assembly and a second voice coil, the second voice coil is inserted in the second magnetic gap.

8. A wearable device, characterized in that: The device comprises a sound emitting device according to any one of claims 1 to 7.

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