A speaker module and a smart wearable device

Abstract

This application discloses a speaker module and a smart wearable device. The speaker module includes a module housing, within which a speaker unit is housed. The speaker unit divides the speaker module's internal cavity into a front acoustic cavity and a rear acoustic cavity. The module housing has a vent hole connecting the rear acoustic cavity to the outside and a sound outlet hole connecting the front acoustic cavity to the outside. The sound outlet hole is located on a first sidewall of the front acoustic cavity. The distance from the center of the speaker unit to the second sidewall opposite the sound outlet hole is not less than 8.5 mm. The speaker module also includes an auxiliary sound hole, which is connected to the side of the front acoustic cavity opposite the sound outlet hole. The auxiliary sound hole is located adjacent to the vent hole, and the auxiliary sound hole and the sound outlet hole form a dipole structure with the vent hole. The technical solution of this application can solve the problem of standing wave interference, improve sound leakage, and enhance the sound output of the speaker module.

Description

Technical Field

[0001] This application relates to the field of electroacoustic equipment technology, and more particularly to a loudspeaker module and a smart wearable device. Background Technology

[0002] With the popularization and widespread adoption of smart wearable devices, more and more of these devices are incorporating acoustic functions. For example, wearable audio devices such as audio glasses and portable headsets use near-ear speaker technology compared to traditional headphones, which prevents auditory fatigue and hearing damage even after prolonged listening.

[0003] As smart wearable devices continue to evolve towards thinner and lighter designs, speaker modules in these devices are often designed with a side-emitting structure. When a side-emitting speaker module is in operation, some sound waves cannot be directly radiated from the sound outlet. These sound waves must be reflected by the front acoustic cavity sidewall of the speaker module before they can be radiated from the sound outlet. At this time, the phase superposition of the emitted and reflected waves of certain frequency bands will form a standing wave, causing a sharp decrease in sound pressure at that frequency. This results in a deep valley in the speaker module's sound sensitivity curve near that frequency, severely affecting the speaker module's sound sensitivity in that frequency band and impacting the audio performance of the wearable device. Summary of the Invention

[0004] This application provides a speaker module and a smart wearable device to improve the standing wave problem of smart wearable devices.

[0005] The embodiments of this application adopt the following technical solutions:

[0006] In a first aspect, embodiments of this application provide a loudspeaker module, comprising: a loudspeaker unit housed within a module housing, the loudspeaker unit dividing the inner cavity of the loudspeaker module into a front acoustic cavity and a rear acoustic cavity; the module housing having a vent hole communicating with the rear acoustic cavity to the outside and a sound outlet hole communicating with the front acoustic cavity to the outside; the sound outlet hole being disposed on a first sidewall of the front acoustic cavity; the distance from the center position of the loudspeaker unit to a second sidewall opposite to the sound outlet hole being not less than 8.5 mm; the loudspeaker module further comprising: an auxiliary sound hole communicating with the side of the front acoustic cavity opposite to the sound outlet hole; the auxiliary sound hole being disposed adjacent to the vent hole; and the auxiliary sound hole and the sound outlet hole forming a dipole structure with the vent hole respectively.

[0007] Optionally, the speaker module includes multiple sound leakage holes, with the one having the largest sound leakage area being the main sound leakage hole, and the auxiliary sound leakage holes being disposed adjacent to the main sound leakage hole.

[0008] Optionally, the speaker module includes a plurality of sound vents, the plurality of sound vents having the same sound venting area, and the plurality of sound vents being arranged around the outer periphery of the auxiliary sound hole.

[0009] Optionally, the auxiliary sound hole and the sound leakage hole are located on the same surface.

[0010] Optionally, the auxiliary sound hole is connected to the front sound cavity through an auxiliary sound guide tube, and the sound leakage hole is connected to the rear sound cavity through a sound leakage guide tube. The auxiliary sound guide tube and the sound leakage guide tube are independently arranged within the module housing, and the auxiliary sound guide tube and the sound leakage guide tube share a common sound guide wall.

[0011] Optionally, the auxiliary sound hole is connected to the front sound cavity through an auxiliary sound guide tube. The inlet end of the auxiliary sound guide tube is provided with an outlet hole, which is located on the second side wall. The outlet hole and the sound outlet hole are respectively located at both ends of the length direction of the front sound cavity.

[0012] Optionally, the ratio of the opening area of ​​the lead-out hole to the opening area of ​​the sound outlet hole is 1 / 5 to 1 / 3.

[0013] Optionally, the auxiliary sound hole is connected to the front sound cavity through an auxiliary sound guide tube, and the auxiliary sound guide tube is in the shape of a straight pipe or a spiral pipe; and / or, the cross-sectional shape of the auxiliary sound guide tube is circular or polygonal.

[0014] Optionally, the module housing includes an upper module housing and a lower module housing, the auxiliary sound hole is connected to the front sound cavity through an auxiliary sound guide tube, and the auxiliary sound guide tube is disposed in the lower module housing, wherein the auxiliary sound guide tube and the lower module housing are integrally injection molded; or, the auxiliary sound guide tube and the lower module housing are formed as separate parts, and the auxiliary sound guide tube is bonded to the lower module housing or ultrasonically welded to it.

[0015] Secondly, embodiments of this application also provide a smart wearable device, including: a speaker module, wherein the speaker module is the aforementioned speaker module.

[0016] Optionally, the smart wearable device in this application embodiment further includes: a device housing, the device housing including at least a front cavity main sound hole, a front cavity secondary sound hole and a rear cavity sound outlet hole; the front cavity main sound hole is connected to the sound outlet hole of the speaker module, the front cavity secondary sound hole is connected to the auxiliary sound hole of the speaker module, and the rear cavity sound outlet hole is connected to the sound leakage hole of the speaker module.

[0017] Optionally, the smart wearable device further includes: a device housing, wherein at least a portion of the module housing is formed as the device housing.

[0018] The above-described technical solutions adopted in the embodiments of this application can achieve the following beneficial effects:

[0019] In this embodiment, the speaker module's sound outlet is located on the side wall of the speaker unit. The speaker unit divides the entire module's internal cavity into a front acoustic cavity and a rear acoustic cavity. When the distance between the sound source and the reflecting surface of the front acoustic cavity (i.e., the side wall of the front acoustic cavity relative to the sound outlet) is a quarter wavelength at certain frequencies, the emitted and reflected sound waves will superimpose and form standing wave interference within the front acoustic cavity. In this embodiment, an auxiliary sound hole is provided on the side of the front acoustic cavity opposite to the sound outlet. The reflected wave is guided to the outside of the speaker module through the auxiliary sound hole, avoiding standing wave interference between the reflected and emitted sound waves and improving the sensitivity in the mid-to-high frequency range. Furthermore, in this embodiment, the auxiliary sound hole is located near the sound leakage hole, forming a dipole structure with the sound leakage hole. The closely spaced dipole structure cancels out the far-field frequency response of the radiated sound waves, improving the sound leakage problem of the speaker module and enhancing the privacy of the device. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0021] Figure 1 This is a schematic diagram of the exploded structure of the speaker module shown in the embodiments of this application;

[0022] Figure 2 This is a schematic diagram illustrating the simulation effect of the speaker module shown in the embodiments of this application;

[0023] Figure 3 This is a perspective view of the speaker module shown in the embodiments of this application;

[0024] Figure 4 This is a schematic diagram of the appearance of the speaker module shown in the embodiments of this application;

[0025] Figure 5 This is a comparative schematic diagram of the frequency response curves of a 5cm free field shown in the embodiments of this application;

[0026] Figure 6 This is a comparative schematic diagram of the frequency response curves of a 30cm free field shown in the embodiments of this application;

[0027] In the figure: module upper shell 11, module lower shell 12, first side wall 13, second side wall 14, speaker unit 20, first sound vent 30, sound venting tube 310, second sound vent 31, auxiliary sound hole 32, auxiliary sound tube 321, lead-out hole 322, sound outlet hole 40, front sound cavity 50, rear sound cavity 60. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] In this application, the directions referred to as "direction" all refer to the direction of the vibration system of the speaker unit, and the directions referred to as "direction" all refer to the direction of the magnetic circuit system of the speaker unit; the "inner side" referred to in this application all refer to the side located inside the module cavity, and the "outer side" all refer to the side located outside the module cavity.

[0030] The technical solutions provided by the various embodiments of this application are described in detail below with reference to the accompanying drawings.

[0031] The speaker module according to the first aspect of this application, such as Figure 1 and Figure 2 As shown, the speaker module of this embodiment includes a module housing, which may include, for example, the following: Figure 1 The upper housing 11 and lower housing 12 of the module are shown. The module housing contains a speaker unit 20, which divides the internal cavity of the speaker module into a front acoustic cavity 50 and a rear acoustic cavity 60, and refers to... Figure 3 and Figure 4 The module housing is provided with a sound vent (30, 31) connecting the rear acoustic cavity 60 to the outside and a sound outlet 40 connecting the front acoustic cavity 50 to the outside. The sound outlet 40 is located on the first side wall 13 of the front acoustic cavity 50.

[0032] In practical applications, the speaker modules used in smart wearable devices typically have relatively large and long speaker units 20. The distance from the center of the speaker unit 20 to the second sidewall 14 opposite the sound outlet 40 is generally not less than 8.5 mm. (Reference) Figure 2 The first sidewall 13 is the front acoustic cavity sidewall of the first short axis of the speaker unit in the front acoustic cavity. This front acoustic cavity sidewall is part of the module housing. The second sidewall 14 is the front acoustic cavity sidewall of the second short axis of the speaker unit in the front acoustic cavity. The first sidewall 13 and the second sidewall 14 are opposite sidewalls of the front acoustic cavity 50. The distance between the first sidewall 13 and the second sidewall 14 is greater than 17mm.

[0033] Studies have found that, for example Figure 2In the speaker module with a side-emitting structure shown, due to the relatively long front acoustic cavity 50, sound waves in the frequency range of 3kHz to 6kHz will be reflected at the second side wall 14. The reflected sound waves and the emitted sound waves in this frequency range superimpose to cause standing wave interference, resulting in a trough in the frequency range of 3kHz to 6kHz. (Refer to...) Figure 5 The proposed solution generates a trough near the 6kHz frequency, which severely affects the sensitivity of the speaker module in this frequency band.

[0034] To address this issue, the speaker module of this embodiment includes an auxiliary sound hole 32. The auxiliary sound hole 32 is connected to the side of the front acoustic cavity 50 opposite to the sound outlet 40. The auxiliary sound hole 32 is positioned adjacent to the vent holes (30, 31). The auxiliary sound hole 32 guides the reflected sound waves from the front acoustic cavity 50 to the outside, preventing the reflection and emission sound waves from superimposing and causing standing wave interference. The speaker module of this embodiment effectively improves the sensitivity of the speaker module in the mid-to-high frequency range. (Refer to...) Figure 5 In this embodiment, the speaker module has a flatter frequency response curve in the mid-to-high frequency range, which improves the acoustic performance of the speaker module.

[0035] Considering the technological differences between smart wearable devices and traditional headphones, smart wearable devices offer less privacy and require careful attention to minimize sound leakage. One common technology to prevent leakage employs an open design for the rear acoustic cavity 60, setting the phase of the sound wave from the vent hole connected to the rear acoustic cavity 60 to be opposite to the phase of the sound wave from the outlet hole 40 connected to the front acoustic cavity 50. However, in smart wearable devices, such as smart glasses, the outlet hole 40 is typically positioned close to the ear, and a certain distance must be maintained between the vent hole and the outlet hole 40 to avoid affecting the loudness of the radiated sound waves. Research has found that the cancellation effect of the far-field frequency response of the radiated sound waves between the vent hole and the outlet hole 40 is related to their distance; the closer the distance, the better the cancellation effect. However, to ensure good loudness of the radiated sound waves from the outlet hole 40, the distance between them cannot be too close. Figure 6 The graph shown is a curve of loudspeaker loudness as a function of frequency. Figure 6 It can be clearly seen that the loudspeaker in the existing solution has a relatively high volume at a distance of 30cm, and the sound leakage in the far field is quite obvious.

[0036] To address this issue, this embodiment sets up an auxiliary sound hole 32 and a sound outlet hole 40 to form a dipole structure with the sound outlet holes (30, 31), respectively. The auxiliary sound hole 32 is adjacent to the sound outlet holes (30, 31). The auxiliary sound hole 32 is in phase with the sound outlet hole 40, but out of phase with the sound outlet holes (30, 31), thus forming a double dipole structure. Figure 6As shown, compared to the single dipole structure used in related technologies between the sound vent of the rear acoustic cavity 60 and the sound outlet 40 of the front acoustic cavity 50, this embodiment adds another dipole structure between the auxiliary sound hole 32 and the sound vent, based on the single dipole structure. This newly added dipole structure is closer together, and by guiding the reflected sound waves from the front acoustic cavity 50, which causes standing wave interference, to the vicinity of the sound vent, the far-field frequency response of the guided sound waves cancels out the sound waves guided from the rear acoustic cavity 60 by the sound vent, further reducing the far-field frequency response of the speaker module and improving the far-field sound leakage problem. Figure 6 It can be clearly seen that, within the range of 100Hz-3000Hz, the far-field loudness of the proposed solution is 3dB-20dB lower than that of the existing solution, effectively improving the problem of far-field sound leakage.

[0037] To facilitate understanding of the various embodiments of this application, the specific structure of the speaker module in a particular embodiment of this application is described in detail below.

[0038] The loudspeaker unit 20 includes a frame, a vibration system, and a magnetic circuit system. The vibration system includes a diaphragm fixed to the frame at its edge, a dome fixed to the center of the diaphragm, and a voice coil fixed to the side of the diaphragm near the magnetic circuit system. The voice coil winding has a lead wire at its end, which is electrically connected to an external circuit. The magnetic circuit system includes a magnetic yoke, a center magnet, a side magnet, and a washer. The outer periphery of the magnetic yoke is fixed to the frame, and the center magnet and side magnet are sequentially fixed to the center of the magnetic yoke. A magnetic gap is provided between the washer on the upper surface of both the center magnet and the side magnet. The end of the voice coil is located in the magnetic gap. The voice coil moves up and down within the magnetic gap according to the magnitude and direction of the acoustic signal passing through its winding. The diaphragm vibrates with the up and down movement of the voice coil, driving the air to produce sound, thereby completing the energy conversion between electroacoustic and phono-acoustic signals.

[0039] The diaphragm of the speaker unit 20 divides the entire speaker module's internal cavity into two chambers: a front acoustic cavity 50 and a rear acoustic cavity 60. Generally, the upper module shell 11, a portion of the lower module shell 12, and the diaphragm together form the front acoustic cavity 50, while the diaphragm and another portion of the lower module shell 12 together form the rear acoustic cavity 60. With reference to the two surfaces of the diaphragm, the first surface with the dome mounted is located in the front acoustic cavity 50, and the second surface opposite to the first surface is located in the rear acoustic cavity 60. Here, this embodiment exemplifies that the module housing includes an upper module shell 11 and a lower module shell 12. In practical applications, the module housing can also have other structures, such as being formed by combining more shells or being integrally molded.

[0040] The initial sound wave radiated by the diaphragm to the front acoustic cavity 50 and the initial sound wave radiated to the rear acoustic cavity 60 are out of phase. Based on this, in order to achieve the effect of reducing the far-field frequency response through the auxiliary sound hole 32, the shape and length of the auxiliary sound guide tube 321 can be adjusted to achieve the desired effect.

[0041] For example, a first frequency band is determined where the frequency response of the sound waves radiated by the sound outlet 40 and the sound vent (30,31) cancels each other out. By setting the shape and length of the auxiliary sound guide tube 321, a second frequency band is obtained where the frequency response of the sound waves radiated by the auxiliary sound outlet 32 ​​and the sound vent (30,31) cancels each other out. The second frequency band and the first frequency band can be not exactly the same; for example, the second frequency band can be a frequency band outside the range of the first frequency band. In this way, the problem of far-field sound leakage of the loudspeaker module is improved by cooperating with the sound outlet 40 and the auxiliary sound outlet 32.

[0042] Of course, in practical applications, those skilled in the art can flexibly set the frequency bands at which the auxiliary sound hole 32 and the sound leakage hole cancel each other out, and this embodiment does not impose specific limitations on this.

[0043] like Figure 3 As shown, in some embodiments of this application, the auxiliary sound hole 32 is connected to the front sound cavity 50 through the auxiliary sound guide tube 321, and the sound leakage hole (30,31) is connected to the rear sound cavity 60 through the sound leakage guide tube 310. The auxiliary sound guide tube 321 and the sound leakage guide tube 310 are independently arranged in the module housing to avoid the sound waves led out by the auxiliary sound guide tube 321 and the sound leakage guide tube 310 from not canceling the near-field frequency response inside the product.

[0044] In this embodiment, the auxiliary sound hole 32 is connected to the front acoustic cavity 50 via an auxiliary sound guide tube 321. The inlet end of the auxiliary sound guide tube 321 is provided with an outlet hole 322, which is located on the second sidewall 14. The outlet hole 322 and the sound outlet hole 40 are respectively located at opposite ends of the length direction of the front acoustic cavity 50. For example, the sound outlet hole 40 is located in the first minor axis direction of the front acoustic cavity 50, and the outlet hole 322 is located in the second minor axis direction of the front acoustic cavity 50. The first and second minor axis directions are the directions of the two relatively short sides of the rectangular loudspeaker unit 20. Thus, by placing the outlet hole 322 on the second sidewall 14 away from the sound outlet hole 40, reflected sound waves generated by the sidewall of the front acoustic cavity 50 can be effectively extracted.

[0045] In some optional embodiments of this application, reference is made to Figure 3 The lead-out hole 322 is provided, for example, at the junction of the major and minor axes of the speaker unit 20 on the second side wall 14. Of course, it can also be provided at other positions on the second side wall 14. This embodiment does not impose specific limitations.

[0046] According to some embodiments of the present invention, in this embodiment, the ratio of the opening area of ​​the lead-out hole 322 to the opening area of ​​the sound outlet hole 40 is 1 / 5 to 1 / 3. The opening area of ​​the lead-out hole 322 should not be too small. If the lead-out hole 322 is too small, it cannot effectively guide the reflected sound waves caused by the second side wall 14. If the lead-out hole 322 is too large, it will affect the loudness of the sound outlet hole 40.

[0047] In some embodiments of the present invention, such as Figure 3 As shown, the auxiliary sound guide tube 321 and the sound leakage sound guide tube 310 share a common sound guide wall, which effectively reduces the volume occupied by the auxiliary sound guide tube 321 in the rear acoustic cavity 60 and avoids affecting the low-frequency performance of the rear acoustic cavity 60. It should be understood that in practical applications, those skilled in the art can flexibly adjust the position and number of the auxiliary sound guide tubes 321, for example, by setting two or more auxiliary sound guide tubes 321, with the outlet holes 322 of each auxiliary sound guide tube 321 located at different positions.

[0048] Optionally, taking the aforementioned module housing including the upper module housing 11 and the lower module housing 12 as an example, the auxiliary sound guide tube 321 in this embodiment is disposed on the lower module housing 12. The auxiliary sound guide tube 321 and the lower module housing 12 are integrally injection molded, for example, or the auxiliary sound guide tube 321 and the lower module housing 12 are formed as separate parts, and the auxiliary sound guide tube 321 and the lower module housing 12 are bonded and fixed or ultrasonically welded.

[0049] According to some embodiments of this application, the auxiliary sound guide tube 321 is in the shape of a straight pipe, a spiral pipe, or other shapes; for example, the cross-sectional shape of the auxiliary sound guide tube 321 is circular or polygonal.

[0050] It should be understood that, in practical applications, those skilled in the art, guided by the embodiments of this application, should flexibly select the number, length, position, shape, and installation method of the auxiliary sound guide tubes 321, and the exemplary solutions shown above in this embodiment should not be regarded as limiting solutions.

[0051] According to some embodiments of this application, the speaker module may include multiple vent holes, such as Figure 4 As shown, for example, it includes a first sound leakage hole 30 and a second sound leakage hole 31, wherein the sound leakage areas of the multiple sound leakage holes can be the same or different. When the sound leakage areas of the multiple sound leakage holes are different, the first sound leakage hole 30 with the largest sound leakage area is the main sound leakage hole, and the auxiliary sound leakage hole 32 is arranged adjacent to the main sound leakage hole 30. When the sound leakage areas of the multiple sound leakage holes are the same, the multiple sound leakage holes can be arranged around the outer periphery of the auxiliary sound leakage hole 32 to ensure that the sound waves emitted by the auxiliary sound leakage hole 32 and the sound waves emitted by the multiple sound leakage holes cancel each other out over the widest possible frequency range.

[0052] In this embodiment, the proximity of the auxiliary sound hole 32 to the sound leakage hole should be understood as follows: the auxiliary sound guide tube 321 is reasonably arranged in the unused space inside the speaker module cavity, and the auxiliary sound hole 32 is opened at a reasonable position on the module housing as close as possible to the sound leakage hole. The auxiliary sound hole 32 is positioned as close as possible to the sound leakage hole without affecting other components of the speaker module. For example... Figure 4 The auxiliary sound hole 32 shown is on the same surface as the sound leakage hole 30, so that the sound waves emitted by the auxiliary sound hole 32 and the sound waves emitted by the sound leakage hole cancel each other out over the widest possible frequency range.

[0053] The smart wearable device according to the second aspect of this application includes the speaker module according to the above-described embodiments of this application.

[0054] The smart wearable devices in this embodiment include portable head-mounted devices, such as smart glasses, headphones, and HMD (Head-Mounted Display) devices. Smart wearable devices can be AR (Augmented Reality), VR (Virtual Reality), or MR (Mixed Reality) devices.

[0055] In this embodiment, the smart wearable device is provided with at least one speaker module. For example, in smart glasses, a speaker module can be provided at the position of each temple. The number of speaker modules can be flexibly set by those skilled in the art.

[0056] In some embodiments of this application, the speaker module can serve as a peripheral component of a smart wearable device, for example, the speaker module can be detachably installed in the smart wearable device. Alternatively, the speaker module can be assembled within the housing of the smart wearable device. For example, the smart wearable device includes a device shell, which at least includes a front cavity main sound hole, a front cavity secondary sound hole, and a rear cavity sound outlet; the front cavity main sound hole communicates with the sound outlet of the speaker module, the front cavity secondary sound hole communicates with the auxiliary sound hole of the speaker module, and the rear cavity sound outlet communicates with the sound leakage hole of the speaker module.

[0057] In some optional embodiments of this application, the smart wearable device may further include: a device housing, with at least a portion of the module housing formed as the device housing. That is, the speaker module and the smart wearable device can share the same housing. For example, the speaker module housing can be part of the device housing, or the entire speaker module housing can be the device housing. This allows for an integrated module design, where the speaker unit is directly assembled inside the device housing. The speaker unit and the device housing cooperate to define the acoustic cavity of the speaker module, reducing the assembly space occupied by the speaker module and enabling a lightweight and miniaturized design of the smart wearable device.

[0058] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0059] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A speaker module disposed at the temple of smart glasses, comprising a module housing, wherein a speaker unit is housed within the module housing, the speaker unit dividing the inner cavity of the speaker module into a front acoustic cavity and a rear acoustic cavity, and the module housing having a sound vent hole communicating with the rear acoustic cavity to the outside and a sound outlet hole communicating with the front acoustic cavity to the outside, characterized in that, The sound outlet is located on the first sidewall of the front acoustic cavity. The distance from the center of the speaker unit to the second sidewall opposite to the sound outlet is not less than 8.5 mm. The speaker module also includes an auxiliary sound hole, which is connected to the side of the front acoustic cavity opposite to the sound outlet. The auxiliary sound hole guides the reflected wave from the front acoustic cavity to the outside, avoiding the superposition of the reflected wave and the emitted wave to generate standing wave interference. The auxiliary sound hole is located adjacent to the sound vent hole. The auxiliary sound hole and the sound outlet are in the same phase, but opposite in phase to the sound vent hole, and form a double dipole structure with the sound vent hole. The reflected wave from the front acoustic cavity and the sound wave from the rear acoustic cavity guided by the sound vent hole cancel each other out in the far-field frequency response. The auxiliary sound hole is connected to the front sound cavity through an auxiliary sound guide tube. A first frequency band is determined where the frequency response of the sound waves radiated by the sound outlet and the sound outlet cancels out. The shape and length of the auxiliary sound guide tube are changed so that the frequency band where the frequency response of the sound waves radiated by the auxiliary sound hole and the sound outlet cancels out is a second frequency band. The second frequency band is not exactly the same as the first frequency band.

2. The speaker module as described in claim 1, characterized in that, The speaker module includes multiple sound vents, with the one having the largest sound vent area being the main sound vent, and the auxiliary sound vents being located adjacent to the main sound vent.

3. The speaker module as described in claim 1, characterized in that, The speaker module includes multiple sound vents, all of which have the same sound venting area and are arranged around the outer periphery of the auxiliary sound hole.

4. The speaker module as described in claim 1, characterized in that, The auxiliary sound hole and the sound leakage hole are on the same surface.

5. The speaker module as described in claim 1, characterized in that, The sound vent is connected to the rear acoustic cavity through a sound venting guide tube. The auxiliary sound guide tube and the sound venting guide tube are independently arranged inside the module housing. The auxiliary sound guide tube and the sound venting guide tube share a common sound guide wall.

6. The speaker module as described in claim 1, characterized in that, The auxiliary sound hole is connected to the front sound cavity through an auxiliary sound guide tube. The inlet end of the auxiliary sound guide tube is provided with an outlet hole, which is located on the second side wall. The outlet hole and the sound outlet hole are respectively located at both ends of the length direction of the front sound cavity.

7. The speaker module as described in claim 6, characterized in that, The ratio of the opening area of ​​the lead-out hole to the opening area of ​​the sound outlet hole is 1 / 5 to 1 / 3.

8. The speaker module as described in any one of claims 1-7, characterized in that, The auxiliary sound guide tube is either a straight pipe or a spiral pipe. And / or, the cross-sectional shape of the auxiliary sound guide tube is circular or polygonal.

9. The speaker module as described in any one of claims 1-7, characterized in that, The module housing includes an upper module housing and a lower module housing. The auxiliary sound hole communicates with the front sound cavity via an auxiliary sound guide tube, and the auxiliary sound guide tube is located in the lower module housing. The auxiliary sound guide tube is integrally injection molded with the lower shell of the module; Alternatively, the auxiliary sound guide tube and the lower shell of the module can be formed as separate parts, and the auxiliary sound guide tube can be bonded or ultrasonically welded to the lower shell of the module.

10. A smart wearable device, characterized in that, include: A speaker module, wherein the speaker module is the speaker module according to any one of claims 1-9.

11. The smart wearable device as described in claim 10, characterized in that, The smart wearable device further includes: a device housing, the device housing including at least a front cavity main sound hole, a front cavity secondary sound hole and a rear cavity sound outlet hole; the front cavity main sound hole is connected to the sound outlet hole of the speaker module, the front cavity secondary sound hole is connected to the auxiliary sound hole of the speaker module, and the rear cavity sound outlet hole is connected to the sound leakage hole of the speaker module.

12. The smart wearable device as described in claim 10, characterized in that, The smart wearable device further includes: a device housing, wherein at least a portion of the module housing is formed as the device housing.

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