CN118803509A - Sound cavity structure and electronic equipment - Google Patents

Abstract

The embodiments of the present application relate to the technical field of audio products, and disclose a sound cavity structure and an electronic device. The sound cavity structure includes a cavity. The cavity is provided with an inner cavity, a mounting hole connected to the inner cavity and used to connect a speaker, and a sound outlet hole connected to the inner cavity. The inner cavity is provided with a sound propagation channel for transmitting the sound emitted by the speaker to the sound outlet hole, and the sound propagation channel includes at least one layer of sub-channels arranged along the axial direction of the mounting hole, and there are multiple sub-channels located on the same layer. And the lengths of the multiple sub-channels gradually increase in the direction away from the center of the inner cavity, and two adjacent sub-channels are connected to each other. The sound cavity structure and electronic device provided in the embodiments of the present application can enhance the bass effect of electronic equipment at a relatively low cost within a limited space.

Description

Sound cavity structure and electronic equipment

Technical Field

The embodiments of the present application relate to the technical field of audio products, and in particular to a sound cavity structure and an electronic device.

Background Art

Electronic devices that use bass enhancement technology can provide a fuller, deeper and more powerful bass effect, adding dynamism and momentum to the music, allowing listeners to feel the power and charm of the music. Therefore, bass plays an extremely critical role in improving the sound quality of electronic devices.

As electronic devices develop towards miniaturization and thinness, on the one hand, the stiffness of the speaker vibration system will increase, reducing the low-frequency sensitivity of electronic devices; on the other hand, the space reserved for the sound cavity structure of electronic devices is very limited, and a small sound cavity will increase the resonance frequency of the sound cavity structure, further reducing the low-frequency sensitivity of electronic devices, making the sound quality sound lacking low-frequency components. As people's experience with entertainment projects such as music, movies, and games becomes richer and richer, the demand for bass in electronic devices is also increasing. However, existing bass enhancement technologies are either not applicable to small speakers or are costly. Therefore, how to enhance the bass effect of electronic devices at a lower cost in a limited space is an urgent problem to be solved.

Summary of the invention

The purpose of the embodiments of the present application is to provide a sound cavity structure and an electronic device, which can enhance the bass effect of the electronic device in a limited space at a relatively low cost.

In order to solve the above technical problems, the embodiments of the present application provide a sound cavity structure. The sound cavity structure includes a cavity. The cavity has an inner cavity, and the cavity wall of the cavity is provided with a mounting hole and a sound outlet hole connected to the inner cavity, and the mounting hole is used to set a speaker, and the speaker faces the outside; the inner cavity is provided with a sound propagation channel connected to the sound outlet hole, and the sound propagation channel is used to propagate the sound emitted from the back of the speaker to the outside; the sound propagation channel includes a plurality of sub-channels arranged in a direction away from the center of the inner cavity, and the lengths of the plurality of sub-channels gradually increase, and adjacent sub-channels in the plurality of sub-channels are connected to each other, and the sub-channel farthest from the center of the inner cavity among the plurality of sub-channels is connected to the sound outlet hole.

An embodiment of the present application further provides an electronic device, comprising the above-mentioned sound cavity structure.

The sound cavity structure and electronic device provided by the embodiments of the present application are provided with a sound propagation channel in the inner cavity of the cavity located at the back of the speaker, that is, in the rear sound cavity. The lengths of the multiple sub-channels constituting the sound propagation channel vary gradiently in the direction away from the center of the inner cavity, and the sub-channels are connected for sound propagation. The rear sound cavity formed with a curved channel has a lower acoustic modal frequency, and its acoustic mode can couple and resonate with the structural mode of the speaker to enhance the bass component of the electronic device. The cavity with a sound propagation channel is easy to manufacture, which can save the manufacturing cost of the sound cavity structure. Therefore, by providing a sound propagation channel in the inner cavity, the purpose of enhancing the bass component of the electronic device at a lower cost within a limited space is achieved.

In some embodiments, a plurality of sound propagation channels are evenly distributed in the axial direction around the mounting hole, and the region where each sound propagation channel is located is provided with two edge portions, and a plurality of isolation portions are arranged in sequence between the two edge portions and in a direction away from the center of the inner cavity, and the space between two adjacent isolation portions forms a sub-channel, and the plurality of sub-channels are connected end to end in sequence. In this way, by providing a plurality of sound propagation channels in the axial direction around the mounting hole in the second region, the bass of the sound at different directions can be enhanced.

In some embodiments, the cavity is configured in a prism shape, each partition is configured in a flat plate shape, and each partition is configured parallel to the same side of the cavity. In this way, a curved channel consisting of multiple layers of linear channels can be formed in the second region through the flat plate-shaped partitions.

In some embodiments, the cavity is configured in a prism shape, each partition includes a first portion and a second portion connected to each other, and the first portion and the second portion of each partition are arranged parallel to different sides of the cavity. In this way, a curved channel composed of multiple layers of folded-line channels can be formed in the second region through the curved partition.

In some embodiments, the sound propagation channel includes a multi-layer structure arranged in layers along the axial direction of the mounting hole, each layer of the structure includes a plurality of sub-channels; in the axial direction of the mounting hole, the sub-channel at the end point of sound propagation in each layer of the structure is connected to the sub-channel at the start point of sound propagation in the next layer of the structure. In this way, a longer acoustic propagation channel can be formed.

In some embodiments, the projection of the sound propagation channel along the axial direction of the mounting hole is spiral, so that a spiral curved channel for sound propagation can be formed.

In some embodiments, the inner cavity is provided with a plurality of isolators surrounding the same center, the space between two adjacent isolators forms a sub-channel, each isolator is provided with a notch, and two adjacent sub-channels are connected via the notch. In this way, a plurality of isolators can be used to isolate and form a multi-layer channel, and the notches on the isolators can be used to connect the multi-layer channels to form a curved channel for sound propagation.

In some embodiments, a plurality of sound propagation channels are provided along the axial direction of the mounting hole. In this way, a plurality of sound outlet holes can be provided axially around the mounting hole to radiate sound in different directions.

In some embodiments, the sound outlet hole and the mounting hole are arranged on the same plane, so that the sounds of different components can be propagated in the same direction.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

FIG1 is a schematic diagram of a three-dimensional structure of an electronic device in the prior art;

FIG2 is a schematic cross-sectional view of an electronic device in the prior art;

FIG3 is a schematic diagram of a three-dimensional structure of an electronic device provided in some embodiments of the present application;

FIG4 is a schematic diagram of the main structure of an electronic device provided in some embodiments of the present application;

Fig. 5 is a schematic cross-sectional view of the structure along the A-A direction in Fig. 4;

Fig. 6 is a schematic cross-sectional view of the structure along the B-B direction in Fig. 4;

FIG7 is a schematic diagram of a three-dimensional structure of an electronic device provided in some other embodiments of the present application;

FIG8 is a schematic diagram of the main structure of an electronic device provided in some other embodiments of the present application;

Fig. 9 is a schematic cross-sectional view of the structure along the C-C direction in Fig. 8;

Fig. 10 is a schematic cross-sectional view of the structure along the D-D direction in Fig. 8;

FIG11 is a schematic diagram of a three-dimensional structure of an electronic device provided in some other embodiments of the present application;

FIG12 is a schematic diagram of the main structure of an electronic device provided in some other embodiments of the present application;

FIG13 is a schematic cross-sectional view of the structure along the E-E direction in FIG12;

FIG14 is a schematic cross-sectional view of the structure along the F-F line in FIG12;

FIG15 is a schematic diagram of a three-dimensional structure of an electronic device provided in yet other embodiments of the present application;

FIG16 is a schematic diagram of the main structure of an electronic device provided in some other embodiments of the present application;

FIG17 is a schematic cross-sectional view of the structure along the G-G line in FIG16 ;

FIG18 is a schematic cross-sectional view of the structure along the H-H direction in FIG16 ;

FIG19 is a schematic diagram of a three-dimensional structure of an electronic device provided in yet other embodiments of the present application;

FIG20 is a schematic diagram of the main structure of an electronic device provided in some other embodiments of the present application;

Fig. 21 is a schematic cross-sectional view of the structure along the line I-I in Fig. 20;

FIG22 is a schematic cross-sectional view of the structure along the J-J line in FIG20 ;

FIG23 is a schematic diagram of a three-dimensional structure of an electronic device provided in yet other embodiments of the present application;

FIG24 is a schematic diagram of the main structure of an electronic device provided in some other embodiments of the present application;

Fig. 25 is a schematic cross-sectional view of the structure along the K-K direction in Fig. 24;

Fig. 26 is a schematic cross-sectional view of the structure along the L-L direction in Fig. 24;

FIG27 is a schematic diagram of a three-dimensional structure of an electronic device provided in yet other embodiments of the present application;

FIG28 is a schematic diagram of the main structure of an electronic device provided in some other embodiments of the present application;

Fig. 29 is a schematic cross-sectional view of the structure along the M-M direction in Fig. 28;

FIG30 is a schematic cross-sectional view of the structure along the N-N direction in FIG28;

FIG31 is a comparison diagram of the numerical calculation sensitivity of electronic devices provided by some embodiments of the present application and electronic devices in the prior art;

FIG32 is a comparison chart of the numerical calculation sensitivity of electronic devices provided in some other embodiments of the present application and electronic devices in the prior art.

DETAILED DESCRIPTION

To make the technical solutions and advantages provided by the present application clearer, each embodiment of the present application will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in each embodiment of the present application, many technical details are proposed in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present application can also be implemented. The division of the following embodiments is for the convenience of description, and should not constitute any limitation on the specific implementation of the present application, and the various embodiments can be combined with each other and referenced to each other without contradiction.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

With the continuous development of electronic technology, the audio effects of various electronic devices are getting better and better, allowing listeners to have an immersive experience. This depends not only on good audio recording quality, but also on good audio playback quality. In various electronic devices used to play audio, in order to prevent the sound emitted from the front and back of the speaker diaphragm from short-circuiting, the speaker needs to be installed in a closed sound cavity structure, but a too small sound cavity structure will cause the resonant frequency to rise, reduce the low-frequency sensitivity of the electronic device, and make the sound quality sound lacking in low-frequency components. In order to ensure the playback effect of the low-frequency components of electronic equipment, a larger rear sound cavity is required.

However, as electronic devices such as speakers are becoming smaller and thinner, the space left for the sound cavity structure is very limited. As shown in Figures 1 and 2, the box 100 of the closed speaker only provides a limited sound cavity structure for the speaker 200, and its sound quality lacks low-frequency components. In order to enhance its bass effect, the existing technologies mainly include inverted phase tubes, passive radiators, labyrinth box structures and N'Bass material virtual expansion.

The inverted phase tube is installed on the wall of the rear sound cavity. By making appropriate phase changes to the sound waves radiated from the back of the speaker diaphragm, the phase of the sound waves radiated from the front of the speaker diaphragm is close to the same phase in the main frequency band, which can effectively increase the low-frequency components of the speaker. However, the design and adjustment of the inverted phase tube need to be precise, otherwise phase distortion may be introduced. If the inverted phase tube is poorly designed or manufactured, it is also easy to cause airflow noise problems, and the overall Q value (also known as quality factor) of the speaker is required to be no more than 0.6. It is difficult for a small speaker to achieve an overall Q value below 0.6.

Passive radiators are installed on the wall of the rear sound cavity and can be used to replace the inverted tube to enhance the bass of the speaker and eliminate airflow noise. However, passive radiators are more expensive, less efficient, and have limited low-frequency dive.

The labyrinth-type cabinet structure is bulky and complex, with a large volume, which is prone to airflow noise problems and has high requirements for the airtightness of the cabinet.

Filling the rear sound cavity with N’Bass material can virtually expand the volume of the speaker’s rear sound cavity, thereby enhancing the speaker’s bass and overcoming the sound tailing problem. However, for speakers composed of the same speaker, the smaller the volume of the rear sound cavity, the better the bass enhancement effect of the N’Bass material. The bass enhancement effect of the N’Bass material on speakers with a larger rear sound cavity is very limited, and the price is very expensive. It is currently mainly used to improve the acoustic performance of speakers in mid-to-high-end small consumer electronic products such as mobile phones, tablets and laptops, limiting the wider application of this type of material.

Therefore, for electronic devices that play audio, such as home speakers, car speakers, conference system speakers, stage speakers, and professional studio speakers, it is necessary to develop a low-cost bass enhancement technology that can be applied in a limited space to provide greater flexibility for the miniaturization of electronic devices and ID (Industrial Design) design.

Some embodiments of the present application take advantage of the miniaturization and lightweight of acoustic metamaterials and propose a sound cavity structure based on acoustic metamaterials. Part of the structure of the cavity is composed of a sound propagation channel, and one end of the sound propagation channel is connected to the back sound-emitting area of the speaker, and the other end is connected to the outside atmosphere. Compared with conventional bass reflex tubes, the sound propagation channel has more internal channels, which are smaller and longer, and are distributed in a gradient. When sound waves pass through the sound propagation channel, they propagate along the curved channel, which can effectively block the medium and high frequency noise in the sound cavity behind the speaker, improve the airflow noise, and is expected to obtain a lower low-frequency dive, and the overall Q value requirements for the speaker are lower. The cavity with a sound propagation channel can be manufactured by a mold or by 3D (Dimension) printing, which is easy to manufacture and can save the manufacturing cost of the sound cavity structure.

In the sound cavity structure provided in some embodiments of the present application, the bass enhancement mechanism utilizes the coupled resonance of the first-order acoustic mode of the cavity and the first-order structural mode of the speaker, which, on the one hand, enhances the sound waves radiated from the diaphragm of the speaker to the front, and on the other hand, the sound waves on the back of the speaker diaphragm, after passing through the sound propagation channel, are nearly in phase with the sound waves on the front of the speaker diaphragm within a certain frequency band, further enhancing the bass effect of the speaker. It should be noted that the amplitude of the mid- and high-frequency sound waves on the back of the speaker diaphragm after passing through the sound propagation channel is much smaller than the amplitude of the sound waves radiated from the speaker diaphragm to the front, so the sound propagation channel has very little effect on the mid- and high-frequency sound when the electronic device plays sound.

The sound cavity structure in the electronic device provided in some embodiments of the present application is explained below in conjunction with Figures 3 to 30.

As shown in FIGS. 3 to 30 , the sound cavity structure provided in some embodiments of the present application includes a cavity 11. The cavity 11 has an inner cavity 101, and a mounting hole 102 and a sound outlet 103 connected to the inner cavity 101 are provided on the cavity wall of the cavity 11. The mounting hole 102 is used to set a speaker 20, and the speaker 20 faces the outside. The inner cavity 101 is provided with a sound propagation channel 12 connected to the sound outlet 103, and the sound propagation channel 12 is used to propagate the sound emitted by the speaker 20 to the outside. The sound propagation channel 12 includes a plurality of sub-channels 121 arranged in a direction away from the center of the inner cavity 101, and the lengths of the plurality of sub-channels 121 gradually increase, and adjacent sub-channels 121 in the plurality of sub-channels 121 are connected to each other, and the sub-channel 121 farthest from the center of the inner cavity 101 in the plurality of sub-channels 121 is connected to the sound outlet 103.

The cavity 11 is used to install the speaker 20 and improve the sound effect of the speaker 20. The inner cavity 101 of the cavity 11 can provide a relatively closed resonant space for the propagation of sound. By changing the space size and internal structure of the inner cavity 101, the resonance characteristics of the cavity 11 can be adjusted, thereby changing the sound quality of the electronic device. The inner cavity 101 includes a first area 111 and a second area 112 surrounding the first area 111. The first area 111 is used to accommodate the speaker 20 and make the speaker 20 face the outside through the mounting hole 102. The second area 112 is provided with a sound propagation channel 12. The mounting hole 102 of the inner cavity 101 is used to install the speaker 20. The sound propagation channel 12 is connected to the outside through the sound outlet hole 103, and the subchannel 121 connected to the sound outlet hole 103 is adjacent to the inner wall surface of the cavity 11. The sound propagation channel 12 is located at the position where the sound is radiated from the back of the speaker 20, that is, the position where the rear sound cavity is located. The rear sound cavity can correct the low frequency. Therefore, by providing the sound propagation channel 12 in the inner cavity 101, the low-frequency component of the sound emitted from the back of the speaker 20 can be enhanced through the resonance characteristics.

The sound propagation channel 12 is formed by a plurality of sub-channels 121 of gradient lengths that are interconnected. The two ends of the sound propagation channel 12 are respectively connected to the back sound-emitting area of the speaker 20 and the outside world, and finally form a curved channel that allows the sound to propagate gradually from the back of the speaker 20 to the outside world connected to the sound outlet 103 of the cavity 11. Such a sub-channel 121 can be arranged around the periphery of the first area 111, which is conducive to making full use of the sound on the back of the diaphragm of the speaker 20 and propagating the low-frequency components of the sound to the outside world. The sub-channel 121 can be in the shape of a straight line, a broken line, a circle or an arc. Among any three adjacent sub-channels 121, the sub-channel 121 located in the middle position is connected to the adjacent sub-channels 121 on both sides at positions far away from each other. The sub-channel 121 can also be in the shape of a spiral.

In the sound cavity structure provided by some embodiments of the present application, a sound propagation channel 12 is arranged in the position where the inner cavity 101 of the cavity 11 surrounds the back of the speaker 20, that is, in the rear sound cavity. The sound propagation channel 12 includes a plurality of sub-channels 121 whose lengths vary gradually along the direction away from the center of the inner cavity 101, and each sub-channel 121 is interconnected to form a curved channel for sound propagation. The sound cavity formed with a curved channel has a lower acoustic mode frequency, and its acoustic mode can couple and resonate with the structural mode of the speaker 20 to enhance the low-frequency component of the electronic device. The cavity with the sound propagation channel 12 is easy to manufacture, which can save the manufacturing cost of the sound cavity structure. Therefore, by setting the sound propagation channel 12 in the inner cavity 101, the purpose of enhancing the bass effect of the electronic device at a lower cost in a limited space is achieved.

It should be noted that the first-order acoustic modal frequency of the rear sound cavity in the sound cavity structure of electronic devices such as small sealed speakers is usually much larger than the first-order structural modal frequency of the speaker 20, so the coupling between the two modes is very weak. As for the sound cavity structure proposed in some embodiments of the present application, without increasing the overall size of electronic devices such as speakers, through appropriate design, such as the length of the curved channel, the cross-sectional size of the sub-channel 121, the number of sound propagation channels 12, etc., the first-order acoustic modal frequency of the open cavity composed of the sound propagation channel 12 and the first area 111 of the inner cavity 101 can be lower than the first-order structural modal frequency of the speaker 20, that is, the resonant frequency F0 of the speaker 20 monomer, and the two modes are coupled. On the one hand, the sound waves radiated from the front of the diaphragm of the speaker 20 are enhanced, and on the other hand, the sound waves on the back of the speaker 20 are radiated to the outside through the sound propagation channel 12. In a certain low-frequency range, the phase of the sound waves radiated to the outside through the sound propagation channel 12 is close to the same phase as the phase of the sound waves radiated from the front of the diaphragm of the speaker 20, thereby enhancing the bass of the electronic device. Since the size of each sub-channel 121 of the sound propagation channel 12 is relatively small, most of the sound energy of the medium and high frequency sound waves is blocked from radiating to the outside, so the sound propagation channel 12 has little effect on the medium and high frequencies of electronic equipment.

As shown in Figures 5 and 6, there can be multiple sound propagation channels 12 evenly distributed in the axial direction around the mounting hole 102, and the area where each sound propagation channel 12 is located is provided with two edge portions 122, and a plurality of isolation portions 123 located between the two edge portions 122 and arranged in sequence along the direction away from the center of the inner cavity 101, the space between two adjacent isolation portions 123 forms a sub-channel 121, and the plurality of sub-channels 121 are connected end to end in sequence.

The number of sound propagation channels 12 distributed on the same plane can be two, three, four or more. Different sound propagation channels 12 correspond to different sound outlet holes 103, and the corresponding sub-channels 121 of two adjacent sound propagation channels 12 are in an isolated state.

A subchannel 121 is formed between two adjacent isolating portions 123, and the lengths of the multiple isolating portions 123 increase in a gradient along the direction away from the center of the inner cavity 101, thereby forming multiple subchannels 121 whose lengths increase in a gradient along the direction away from the center of the inner cavity 101. The multiple isolating portions 123 are alternately connected to two edge portions 122, that is, among any three adjacent isolating portions 123, the two isolating portions 123 located at both sides are connected to the same edge portion 122, and there is a gap between one end of each isolating portion 123 that is not connected to the edge portion 122 and the edge portion 122, so that the multiple subchannels 121 are interconnected to form a curved channel.

In addition, the connection between two adjacent sound propagation channels 12 can share the same edge portion 122, which can reduce the space occupied by the edge portion 122 of the sound propagation channel 12, which is beneficial to increase the effective length of the sub-channel 121 and reduce the resonance frequency of the sound cavity.

The innermost sub-channel 121 is connected to the sound-emitting area at the back of the speaker 20, and the outermost sub-channel 121 is connected to the outside through the sound outlet 103, and finally forms a complete passage for the sound to propagate in a direction away from the center of the inner cavity 101 through different sub-channels 121 in sequence. Through the complete passage, the sound emitted from the back of the speaker 20 can be propagated through different sound propagation channels 12 and radiated to the outside through different sound outlets 103, thereby enhancing the low-frequency components of the sound at different directions through the sound propagation channels 12 at different positions.

As shown in FIGS. 7 to 10 , the cavity 11 may be configured to be in a prism shape, each of the isolation portions 123 may be configured to be in a flat plate shape, and each of the isolation portions 123 may be configured to be parallel to the side wall of the cavity 11 .

When the cavity 11 is configured to be prism-shaped, it includes parallel top and bottom walls, and multiple side walls connecting the top and bottom walls. The inner cavity 101 of the cavity 11 is prism-shaped. At this time, each sub-channel 121 of the sound propagation channel 12 can be adjusted to a straight line. That is, the isolation portion 123 can be configured to be flat, and the isolation portion 123 forming the same sound propagation channel 12 is parallel to the same side wall of the cavity 11, that is, multiple sound propagation channels 12 are configured to correspond to the multiple side walls of the cavity 11. The sound outlet 103 can be set at the edge of the side of the cavity 11.

In actual situations, each subchannel 121 of the sound propagation channel 12 can also be adjusted to a folded line shape. That is, as shown in Figures 11 to 14, the cavity 11 can be set to a prism shape, and each isolation part 123 includes a first part 1231 and a second part 1232 connected to each other, and the first part 1231 and the second part 1232 of each isolation part 123 are arranged parallel to different side walls of the cavity 11.

The first part 1231 and the second part 1232 of the isolation part 123 have an angle therebetween, which is consistent with the angle between two adjacent side walls of the cavity 11. The zigzag isolation part 123 can construct a zigzag sub-channel 121 in the second area 112, and can also form a curved channel for sound propagation.

It should be noted that the first part 1231 and the second part 1232 of each isolation part 123 are divisions of the isolation part 123 at different positions. The two parts of each isolation part 123 can be integrally formed, or can be formed separately and connected together.

In some embodiments, as shown in Figures 15 to 18, the sound propagation channel 12 may include a multi-layer structure arranged in layers along the axial direction of the mounting hole 102, and each layer of the structure includes a plurality of sub-channels 121; in the axial direction of the mounting hole 102, the sub-channel 121 at the end point of sound propagation in each layer of the structure is connected with the sub-channel 121 at the starting point of sound propagation in the next layer of the structure.

That is to say, the sub-channels 121 are arranged around the first area 111 and can also be arranged in layers in the axial direction of the mounting hole 102. The sub-channels 121 of different layers are connected to each other at the end of sound propagation, and in the axial direction of the mounting hole 102, only one layer of sub-channels 121 is connected to the outside world, and only one layer of sub-channels 121 is connected to the back sound-emitting area of the speaker 20. If the layer of sub-channels 121 axially away from the speaker 20 in the mounting hole 102 is connected to the back sound-emitting area of the speaker 20 near the center of the inner cavity 101, then the layer of sub-channels 121 axially close to the speaker 20 in the mounting hole 102 is connected to the outside world through the sound outlet hole 103 at a location away from the center of the inner cavity 101. On the contrary, if the sub-channel 121 at the layer axially close to the speaker 20 in the mounting hole 102 is connected to the back sound-emitting area of the speaker 20 near the center of the inner cavity 101, then the sub-channel 121 at the layer axially far from the speaker 20 in the mounting hole 102 is connected to the outside through the sound outlet hole 103 at the center far from the inner cavity 101. In actual situations, the channels 121 of different lengths can be arranged in one layer, three layers, five layers or more odd layers along the axial direction of the mounting hole 102.

By increasing the number of distribution layers of the sub-channels 121 in the axial direction of the mounting hole 102, a longer sound propagation channel 12 can be obtained. The longer sound propagation channel 12 can make the sound cavity structure have a lower resonance frequency, thereby enabling the electronic device to achieve a lower low-frequency dive.

In some embodiments, as shown in FIGS. 19 to 22 , the projection of the sound propagation channel 12 along the axial direction of the mounting hole 102 may be spiral.

When the projection of the sound propagation channel 12 is spiral, a curved channel for sound propagation can also be formed to enhance the low-frequency components in the propagated sound. In actual situations, the center line of the sound propagation channel 12 can be set in the shape of an Archimedean spiral.

In addition, the spiral-shaped sound propagation channel 12 may be provided with multiple layers along the axial direction of the mounting hole 102 , and each layer has a sound outlet hole 103 .

As shown in Figures 23 to 26, the area where the sound propagation channel 12 is located can be provided with multiple isolation members 124 around the same center, and the space between two adjacent isolation members 124 forms a sub-channel 121. Each isolation member 124 is provided with a notch 125, and two adjacent sub-channels 121 are connected via the notch 125.

A plurality of isolators 124 are arranged in multiple circles around the same center on the periphery of the first region 111, and the channels 121 in the gaps are connected through the notches 125 on the isolators 124. The notches 125 of two adjacent isolators 124 are arranged on both sides of the center, so that the outlets of two adjacent channels 121 are located away from each other, and finally a plurality of sub-channels 121 are formed, whose lengths change gradually along the direction away from the center of the inner cavity 101 and are connected to each other to form a curved channel.

In addition, the isolating member 124 may be provided with multiple layers along the axial direction of the mounting hole 102 to form a plurality of sound propagation channels 12. Each sound propagation channel 12 propagates to the outside through a sound outlet hole 103.

In some embodiments, a plurality of sound propagation channels 12 may be provided along the axial direction of the mounting hole 102 .

Each sound propagation channel 12 corresponds to a sound outlet hole 103. By changing the number of sound propagation channels 12 in the axial direction of the mounting hole 102, multiple sound outlet holes 103 can be arranged in the axial direction around the mounting hole 102. In order to adjust the orientation of each sound outlet hole 103, each sound outlet hole 103 radiates sound in different directions.

As shown in FIGS. 27 to 30 , the sound outlet hole 103 may be arranged on the same plane as the mounting hole 102 .

The sound propagation channel 12 is connected to the outside through the sound outlet 103. By locating the sound outlets 103 and 102 on the same plane, the sound emitted by the speaker 20 can be radiated in the same direction, thereby ensuring the gathering effect of sounds of different frequency bands in the same direction.

In actual situations, the sound outlet hole 103 and the mounting hole 102 may also be located on different planes of the cavity 11 .

In actual situations, a mesh cloth may be placed at the location of the sound outlet 103 to reduce the risk of airflow noise and provide physical and dust protection.

Some embodiments of the present application also provide an electronic device, which includes the above-mentioned sound cavity structure.

When designing the sound cavity structure of an electronic device, you can follow the following steps:

Step S10: determine the first-order structural modal frequency of the loudspeaker through experiments or simulations.

Step S20, using finite element method to calculate the acoustic mode of the inner cavity including the sound propagation channel. When calculating the acoustic mode, the sound outlet adopts the pipe end impedance boundary condition. By adjusting the length of the curved channel of the sound propagation channel, the cross-sectional size of the channel, the number of sound propagation channels, etc., the first-order acoustic mode frequency of the inner cavity is lower than the first-order structural mode frequency of the speaker.

The longer the length of the curved channel, the lower the first-order acoustic modal frequency of the inner cavity. The larger the cross-sectional size of the channel, the higher the first-order acoustic modal frequency of the inner cavity. The more the number of sound propagation channels, the higher the first-order acoustic modal frequency of the inner cavity.

Step S30, using finite element calculation to determine the bass enhancement effect of the sound cavity structure provided by the present application on the electronic device, and the sensitivity of the electronic device containing the sound cavity structure provided by the present application and the electronic device containing the closed sound cavity structure with the same overall size. If the bass enhancement effect is not good, repeat step S20 until a satisfactory bass enhancement effect is obtained.

Step S40: Conduct experiments to verify the bass enhancement effect of the sound cavity structure on the electronic device. If the bass enhancement effect is not good, repeat steps S20 and S30 until a satisfactory bass enhancement effect is obtained.

Electronic devices can enhance bass by using the sound cavity structure provided by the present application, which is expected to replace existing bass enhancement technologies such as inverted tubes and passive radiators. The sound cavity structure provided by the present application has broad development prospects in electronic devices including speakers, such as home speakers, car speakers, conference system speakers, stage speakers, and professional studio speakers.

FIG31 takes a speaker as an example, and numerically calculates the sensitivity of a speaker (also called an acoustic metamaterial speaker, as shown in FIG3 ) proposed in some embodiments of the present application and a closed speaker (as shown in FIG1 ) with the same overall size. The volume of the rear sound cavity of the closed speaker is 180cc (cubic centimeter) and the resonant frequency is 205Hz. It can be seen that compared with the closed speaker, within the range below the resonant frequency of the closed speaker, the sensitivity of the speaker provided in some embodiments of the present application is improved by a maximum of 6.4dB/W/m (decibel/watt/meter).

FIG32 shows a comparison of the numerically calculated sensitivity of a speaker proposed by the present application, which has the same structure as that shown in FIG3 but has a different volume, and a closed speaker with the same overall size. The volume of the rear sound cavity of the closed speaker is 466cc (cubic centimeter) and the resonant frequency is 180Hz. It can be seen that compared with the closed speaker, the sensitivity near the resonant frequency of the closed speaker is greatly improved, and in the range below the resonant frequency of the closed speaker, the sensitivity of the speaker provided by some embodiments of the present application is improved by a maximum of 8.6dB/W/m (decibel/watt/meter).

Therefore, the sound cavity structure proposed in some embodiments of the present application can bring better bass enhancement effect to electronic devices.

Compared with the prior art, by setting a sound propagation channel in the sound cavity structure, better low-frequency dive can be obtained, the cavity stiffness can be improved, the risk of noise caused by cavity resonance can be reduced, and reliability can be improved. Compared with the bass reflex tube, the sound propagation channel can effectively block the medium and high frequency noise in the rear sound cavity of the sound cavity structure and reduce the risk of airflow noise. In addition, the sound propagation channel is simple in design and has low requirements on the Q value of the speaker. The overall Q value of the speaker used in the numerical calculation in Figures 31 and 32 is 0.982, which is greater than the maximum value required by the bass reflex tube. At the same time, the sound cavity structure proposed in some embodiments of the present application can enhance the bass effect of electronic equipment, which can greatly reduce costs compared with passive radiators and N'Bass material virtual expansion technology. Compared with the maze-type cabinet, the volume can be greatly reduced.

Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present application, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present application.

Claims (10)

1. A sound cavity structure, characterized in that it comprises a cavity; The cavity has an inner cavity, and a mounting hole and a sound outlet hole connected to the inner cavity are arranged on the cavity wall of the cavity, the mounting hole is used to arrange a speaker, and the speaker faces the outside; The inner cavity is provided with a sound propagation channel connected to the sound outlet, and the sound propagation channel is used to propagate the sound emitted from the back of the speaker to the outside; The sound propagation channel includes a plurality of sub-channels arranged in a direction away from the center of the inner cavity, and the lengths of the plurality of sub-channels gradually increase, adjacent sub-channels among the plurality of sub-channels are connected to each other, and the sub-channel farthest from the center of the inner cavity among the plurality of sub-channels is connected to the sound outlet. 2. The sound cavity structure according to claim 1, characterized in that: There are multiple sound propagation channels evenly distributed axially around the mounting hole, and the area where each sound propagation channel is located is provided with two edge portions, and multiple isolation portions located between the two edge portions and arranged in sequence along the direction away from the center of the inner cavity, the space between two adjacent isolation portions forms the sub-channel, and the multiple sub-channels are connected end to end in sequence. 3. The sound cavity structure according to claim 2, characterized in that: The cavity is configured to be prism-shaped, each of the isolation parts is configured to be flat-plate-shaped, and each of the isolation parts is configured to be parallel to a side wall of the cavity. 4. The sound cavity structure according to claim 2, characterized in that: The cavity is configured to be prism-shaped, each of the isolation parts comprises a first part and a second part that are connected, and the first part and the second part of each of the isolation parts are arranged in parallel with different side walls of the cavity. 5. The sound cavity structure according to any one of claims 1 to 4, characterized in that: The sound propagation channel includes a multi-layer structure arranged in layers along the axial direction of the mounting hole, and each layer of the structure includes the multiple sub-channels; in the axial direction of the mounting hole, the sub-channel at the end point of sound propagation in each layer of the structure is connected with the sub-channel at the starting point of sound propagation in the next layer of the structure. 6. The sound cavity structure according to claim 1, characterized in that: The projection of the sound propagation channel along the axial direction of the mounting hole is spiral. 7. The sound cavity structure according to claim 1, characterized in that: The inner cavity is provided with a plurality of isolating members surrounding the same center, the space between two adjacent isolating members forms the sub-channel, each of the isolating members is provided with a notch, and two adjacent sub-channels are connected via the notch. 8. The sound cavity structure according to claim 6 or 7, characterized in that: The sound propagation channels are arranged in plurality along the axial direction of the mounting hole. 9. The sound cavity structure according to claim 1, characterized in that: The sound outlet hole and the mounting hole are arranged on the same plane. 10. An electronic device, characterized by comprising the sound cavity structure according to any one of claims 1 to 9.