Structure for reducing noise in loudspeaker, and loudspeaker

Abstract

The present application relates to the technical field of loudspeakers, and provides a structure for reducing noise in a loudspeaker, and a loudspeaker. The structure for reducing noise in a loudspeaker is arranged in an acoustic cavity that is defined at least by a housing of the loudspeaker and a loudspeaker unit fixed on the housing; the acoustic cavity is filled with sound-absorbing particles; the structure for reducing noise in a loudspeaker comprises: acoustic enhancement sheets provided in the acoustic cavity; the acoustic enhancement sheets are arranged on some or all inner walls of the acoustic cavity so as to avoid collision between the sound-absorbing particles and the inner walls of the housing; the acoustic enhancement sheets can improve the sound-absorbing performance of the acoustic cavity. The present application can solve the problem in current loudspeakers of noise generated by collision between sound-absorbing particles and the inner walls of a cavity; additionally, the acoustic enhancement sheets are configured to have a sound-absorbing effect, thereby preventing the arrangement of the acoustic enhancement sheets from affecting the sound-absorbing effect.

Description

Noise reduction structure inside the speaker and the speaker

[0001] Related applications

[0002] This application claims priority to Chinese patent application No. 202421833160.X, filed on July 31, 2024, and incorporates the entire contents of the aforementioned patent application as part of this application. Technical Field

[0003] This application relates to the field of loudspeaker technology, and more particularly to a structure for reducing noise within a loudspeaker and a loudspeaker. Background Technology

[0004] With the continuous development of consumer electronics, the pursuit of thinner and lighter electronic devices is gradually increasing, which has brought challenges to the internal speaker components.

[0005] Due to the constraints of speaker shape and the requirements for acoustic performance, acoustic reinforcement particles are usually used in speaker components to address space challenges and performance requirements. In some speaker BOX components with added acoustic reinforcement particles, there may be collision noise caused by the acoustic reinforcement particles hitting the BOX steel sheet or shell during use.

[0006] Existing solutions involve attaching a layer of foam or sound-absorbing cotton inside the BOX shell or steel sheet, allowing the particles to collide with the softer material and reduce impact noise. However, adding a layer of foam further reduces space and affects acoustic performance. While sound-absorbing cotton itself has some acoustic effect, it is relatively limited, and its thickness cannot be as thin as ordinary foam, taking up more space and reducing the amount of acoustic enhancement particles that can be packed in, which also affects the performance of the speaker components. Summary of the Invention

[0007] The purpose of this application is to provide a structure and speaker for reducing noise inside a loudspeaker, solving the problem of noise generated by the collision of sound-absorbing particles with the inner wall of the cavity in current loudspeakers. At the same time, the acoustic reinforcement sheet is set to have a sound-absorbing effect, thereby avoiding the impact of the acoustic reinforcement sheet on the sound absorption effect of the acoustic cavity.

[0008] The above-mentioned technical objectives of this application are mainly achieved through the following technical solutions:

[0009] On one hand, this application provides a structure for reducing noise inside a loudspeaker, which is disposed within a acoustic cavity formed by at least a loudspeaker housing and a loudspeaker unit fixed to the housing, the acoustic cavity being filled with sound-absorbing particles, and the structure for reducing noise inside the loudspeaker includes:

[0010] An acoustic enhancement sheet is disposed within the acoustic cavity, and the acoustic enhancement sheet is disposed on part or all of the inner wall of the acoustic cavity to avoid collision between the sound-absorbing particles and the inner wall of the acoustic cavity. The acoustic enhancement sheet can improve the sound absorption performance of the acoustic cavity, and the hardness of the acoustic enhancement sheet is less than the hardness of the inner wall of the acoustic cavity.

[0011] The noise reduction structure inside the loudspeaker of this application uses an acoustic reinforcement sheet placed inside the loudspeaker's acoustic cavity to isolate the sound-absorbing particles within the cavity and prevent them from colliding with the cavity's inner wall. The acoustic reinforcement sheet has a lower hardness than the cavity's inner wall (the inner wall of the housing and the back of the loudspeaker unit), making it relatively soft. After the sound-absorbing particles collide with the acoustic reinforcement sheet fixed to the cavity's inner wall, no significant noise is generated. Simultaneously, the acoustic reinforcement sheet also possesses acoustic properties, capable of absorbing sound within the cavity, thereby improving the acoustic performance of the cavity filled with sound-absorbing particles and preventing the installation of the acoustic reinforcement sheet from reducing the cavity's sound absorption effect.

[0012] In one optional embodiment of this application, the acoustic enhancement sheet is a powder sheet comprising zeolite material.

[0013] In this embodiment, the acoustic enhancement sheet is a powder sheet made of zeolite material. The powder sheet is a sheet-like structure formed by zeolite powder embedded within fibers, exhibiting low hardness and being relatively softer than the inner wall of the acoustic cavity. Furthermore, because it contains zeolite powder, a commonly used sound-absorbing material, the microporous structure of zeolite provides sound absorption, thus giving the powder sheet corresponding sound-absorbing properties and the ability to acoustically enhance the loudspeaker. In addition, compared to other types of sound-absorbing materials (sound-absorbing cotton, foam, etc.), the powder sheet can be made thinner, thereby reducing the space occupied within the acoustic cavity.

[0014] In one optional embodiment of this application, the acoustic enhancement sheet is bonded and fixed to the inner wall of the acoustic cavity.

[0015] In this embodiment, the acoustic enhancement sheet is attached to the inner wall of the acoustic cavity with glue or double-sided tape, which is convenient to install and facilitates the assembly and shaping of the speaker.

[0016] In one optional embodiment of this application, the acoustic enhancement sheet is disposed on the inner wall of the housing, and / or the acoustic enhancement sheet is disposed on the back side of the speaker unit facing the acoustic cavity.

[0017] In this embodiment, the acoustic enhancement sheet (powder sheet) can be disposed on the inner wall of the housing to prevent the sound-absorbing particles from colliding with the housing; or it can be disposed on the back of the speaker unit to prevent the sound-absorbing particles from colliding with the speaker unit.

[0018] In one optional embodiment of this application, the thickness of the powder sheet is 0.1 mm to 2 mm.

[0019] In an optional embodiment of this application, the housing has an opening opposite to the speaker unit, and a steel sheet is disposed in the opening. The steel sheet, the housing, and the speaker unit enclose the acoustic cavity. The inner wall of the steel sheet forms a steel sheet attachment area, and the inner wall of the housing, which is located on the same plane as the steel sheet, forms a first plastic attachment area. The inner wall of the housing opposite to the first plastic attachment area forms a second plastic attachment area.

[0020] In one optional embodiment of this application, the acoustic reinforcement sheet is adhered and fixed to the steel sheet attachment area.

[0021] In this embodiment, an acoustic enhancement sheet (powder sheet) is attached to the inner side of the steel sheet on the housing. When the speaker is working, the moving sound-absorbing particles no longer collide with the steel sheet and produce noise.

[0022] In an optional embodiment of this application, the acoustic reinforcement sheet is adhered and fixed to the first plastic attachment area and / or the second plastic attachment area.

[0023] In this embodiment, an acoustic enhancement sheet (powder sheet) is attached to the inner side of the plastic shell. When the speaker is working, the moving sound-absorbing particles no longer collide with the shell and produce noise.

[0024] In an optional embodiment of this application, the acoustic reinforcement sheet is adhered and fixed to the steel sheet attachment area, the first plastic attachment area, and the second plastic attachment area.

[0025] In this embodiment, acoustic enhancement sheets (powder sheets) are attached to the inner side of the steel sheet and the inner side of the plastic shell. When the speaker is working, the moving sound-absorbing particles no longer collide with the shell and the steel sheet to produce noise.

[0026] In an optional embodiment of this application, a speaker unit attachment area is formed on the back side of the speaker unit facing the acoustic cavity, and the acoustic reinforcement sheet is attached and fixed to the speaker unit attachment area.

[0027] In this embodiment, an acoustic enhancement sheet (powder sheet) is attached to the back of the speaker unit. When the speaker is working, the moving sound-absorbing particles no longer collide with the speaker unit and generate noise.

[0028] On the other hand, this application also provides a loudspeaker, which includes a housing and a speaker unit fixed on the housing. The housing and the speaker unit surround and form a sound cavity, which is filled with sound-absorbing particles. The sound cavity is provided with the noise reduction structure in the loudspeaker as described above.

[0029] The loudspeaker described in this application has an acoustic enhancement sheet inside that prevents sound-absorbing particles from colliding with the inner wall of the acoustic cavity. No noise generated by the collision of sound-absorbing particles will be produced inside the loudspeaker. Furthermore, the acoustic enhancement sheet has a sound-absorbing effect, which can improve the acoustic enhancement effect of the acoustic cavity inside the loudspeaker. The placement of the acoustic enhancement sheet has little impact on the sound-absorbing particles inside the acoustic cavity. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. The drawings described herein are for illustrative purposes only and are not intended to limit the scope of this application in any way. In addition, the shapes and scales of the components in the drawings are only schematic and used to help understand this application, and are not intended to specifically limit the shapes and scales of the components in this application. Those skilled in the art, under the teachings of this application, can select various possible shapes and scales to implement this application according to specific circumstances. In the drawings:

[0031] Figure 1 is a structural schematic diagram of the first embodiment of the loudspeaker of this application;

[0032] Figure 2 is a structural schematic diagram of the second embodiment of the loudspeaker of this application;

[0033] Figure 3 is a structural schematic diagram of the third embodiment of the loudspeaker of this application.

[0034] Explanation of reference numerals in the attached drawings: 10, housing; 11, top cover; 12, bottom cover; 13, steel sheet; 20, speaker driver; 30, acoustic cavity; 40, sound-absorbing particles; 50, acoustic reinforcement sheet; 60, speaker. Detailed Implementation

[0035] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0036] It should be noted that when an element is referred to as being "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0038] Implementation Method 1:

[0039] As shown in Figures 1 to 3, this application provides a structure for reducing noise inside a loudspeaker. The structure is disposed within a acoustic cavity 30 formed by at least a housing 10 of a loudspeaker 60 and a loudspeaker unit 20 fixed to the housing 10. The acoustic cavity 30 is filled with sound-absorbing particles 40. The structure for reducing noise inside the loudspeaker includes an acoustic enhancement sheet 50 disposed within the acoustic cavity 30. The acoustic enhancement sheet 50 is disposed on part or all of the inner wall of the acoustic cavity 30 to avoid collision between the sound-absorbing particles 40 and the inner wall of the acoustic cavity 30. The acoustic enhancement sheet 50 can improve the sound absorption performance of the acoustic cavity 30. The hardness of the acoustic enhancement sheet 50 is less than the hardness of the inner wall of the acoustic cavity 30.

[0040] The noise reduction structure inside the loudspeaker described in this application uses an acoustic enhancement sheet 50 placed inside the acoustic cavity 30 of the loudspeaker 60 to isolate the sound-absorbing particles 40 inside the acoustic cavity 30, preventing the sound-absorbing particles 40 from colliding with the inner wall of the acoustic cavity 30. The hardness of the acoustic enhancement sheet 50 is less than that of the inner wall of the acoustic cavity 30 (the inner wall of the housing 10 and the back of the loudspeaker unit 20), and it is relatively soft. After the sound-absorbing particles 40 collide with the acoustic enhancement sheet 50 fixed on the inner wall of the acoustic cavity 30, no obvious noise will be generated. At the same time, the acoustic enhancement sheet 50 also has acoustic properties, which can absorb the sound inside the acoustic cavity 30, thereby improving the acoustic performance of the acoustic cavity 30 filled with sound-absorbing particles 40 and preventing the acoustic enhancement sheet 50 from reducing the sound absorption effect of the acoustic cavity 30.

[0041] The following section will provide a detailed description of the structure of each part of the noise reduction structure in the loudspeaker described in this application, as well as the position and connection relationship between each part.

[0042] To illustrate the aforementioned noise reduction structure, a brief description of the speaker 60's structure is provided first. As shown in Figure 1, the speaker 60 typically includes a housing 10 and a speaker unit 20 mounted on the housing 10. For example, the housing 10 includes an upper cover 11 and a lower cover 12 that are fastened together. The speaker unit 20 is fixed to the lower cover 12, and a sound cavity 30 is formed inside the upper cover 11 and the lower cover 12. The speaker unit 20 fixed to the lower cover 12 can serve as part of the sidewall of the sound cavity 30. The housing 10 has a generally flat structure to make the speaker 60 thinner and lighter. Of course, other functional components can also be fixed to the housing 10 according to actual needs. These other functional components, the speaker unit 20, and the housing 10 together form the sound cavity 30. The specific structure of the speaker 60 is not specifically limited here, as long as a corresponding sealed sound cavity 30 can be formed on the rear side of the speaker unit 20.

[0043] Furthermore, to reduce the Fo (lowest resonant frequency) of the loudspeaker 60, improve the low-frequency response, and expand the bandwidth, sound-absorbing material is typically filled into the rear acoustic cavity 30 of the loudspeaker unit 20. The sound-absorbing material effectively reduces the Fo of the loudspeaker 60 and makes the mid-frequency response curve smoother. In this application, the acoustic cavity 30 is filled with sound-absorbing particles 40; for example, the material of the sound-absorbing particles 40 is at least one selected from natural zeolite, activated carbon, silica, sepiolite wool, and zeolite powder.

[0044] The noise reduction structure in the loudspeaker described in this application also includes an acoustic enhancement sheet 50 disposed in the acoustic cavity 30. The acoustic enhancement sheet 50 is disposed on the inner wall of the acoustic cavity 30 to block the sound-absorbing particles 40 in the acoustic cavity 30 and the inner wall of the acoustic cavity 30.

[0045] On the one hand, the hardness of the acoustic reinforcement sheet 50 is less than that of the inner wall of the acoustic cavity 30 (the inner wall of the housing 10 that encloses the acoustic cavity 30, the speaker unit 20, and other functional components fixed to the housing 10). Therefore, the acoustic reinforcement sheet 50 can prevent hard collisions between the sound-absorbing particles 40 and the inner wall of the acoustic cavity 30. Those skilled in the art will understand that hard collisions can cause damage to the inner wall or breakage of the sound-absorbing material particles, and will also generate noise in the speaker 60. In this application, during the operation of the speaker 60, the sound-absorbing particles 40 collide with the softer acoustic reinforcement sheet 50, and almost no sound is produced. No noise is generated in the speaker 60, and the collision with the sound-absorbing particles 40 can provide a certain buffering effect, preventing the sound-absorbing particles 40 from breaking.

[0046] On the other hand, the acoustic enhancement sheet 50 has its own acoustic properties and has the same sound absorption function as the sound-absorbing particles 40. Therefore, the acoustic enhancement sheet 50 can perform the same function as the sound-absorbing particles 40, absorbing the sound in the acoustic cavity 30, thereby improving the acoustic performance of the speaker 60. At the same time, it avoids the problem of the acoustic enhancement sheet 50 occupying the internal space of the acoustic cavity 30, which would lead to a decrease in the acoustic performance of the speaker 60 due to the insufficient filling amount of the sound-absorbing particles 40.

[0047] The following will provide a more detailed description of the structure and technical effects of the optional embodiments of the noise reduction structure within the loudspeaker described in this application.

[0048] According to one embodiment of this application, the acoustic enhancement sheet 50 is a powder sheet comprising zeolite material. The acoustic enhancement sheet 50 is a powder sheet made of zeolite material, which is a sheet-like structure formed by zeolite powder disposed within fibers. It has low hardness and is relatively softer than the inner wall of the acoustic cavity 30. Furthermore, because it contains zeolite powder, and zeolite is a commonly used sound-absorbing material with a microporous structure that provides sound absorption, the powder sheet has corresponding sound-absorbing properties and is capable of producing an acoustic enhancement effect on the loudspeaker 60. In addition, compared to other types of sound-absorbing materials (sound-absorbing cotton, foam, etc.), the powder sheet can be made thinner, thereby reducing the space occupied within the acoustic cavity 30.

[0049] Specifically, the acoustic reinforcement sheet 50 is a sheet composed of zeolite and a matrix material. The matrix material can be glass fiber, polyester fiber, polyurethane, carbon skeleton, or organic skeleton, etc., and the zeolite can be small zeolite particles. First, the zeolite particles, adhesive, and solvent are mixed to form a uniformly dispersed suspension. This suspension is then sprayed or impregnated onto the surface of the sheet-like matrix material, followed by further drying and curing to obtain the powder sheet described above. The use of zeolite material to make powder sheets is a relatively mature technology in this field, and the structure and manufacturing process of the powder sheet will not be further described here.

[0050] The table below shows the values ​​of the lowest resonant frequency (Fo) and sound pressure level (SPL) for different schemes.

[0051] As can be seen from the table above, compared with other solutions, the speaker 60 using the powder film has a lower Fo and a higher SPL, and the speaker 60 has better acoustic performance.

[0052] According to one embodiment of this application, the acoustic enhancement sheet 50 is bonded and fixed to the inner wall of the acoustic cavity 30. The acoustic enhancement sheet 50 is attached to the inner wall of the acoustic cavity 30 using adhesive or double-sided tape, which is convenient and facilitates the assembly of the speaker 60. Double-sided tape has strong adhesion and can be cut to fit different inner wall dimensions, making it very convenient to apply.

[0053] According to one embodiment of this application, the acoustic enhancement sheet 50 is disposed on the inner wall of the housing 10, and / or the acoustic enhancement sheet 50 is disposed on the back side of the speaker unit 20 facing the acoustic cavity 30.

[0054] The acoustic enhancement sheet 50 (powder sheet) can be placed on the inner wall of the housing 10 to avoid the sound-absorbing particles 40 from colliding with the housing 10; or it can be placed on the back of the speaker unit 20 to avoid the sound-absorbing particles 40 from colliding with the speaker unit 20.

[0055] According to one embodiment of this application, the thickness of the powder sheet is 0.1mm-2mm. Optionally, the thickness of the powder sheet is 0.2mm-1.6mm; more preferably, the thickness of the powder sheet is 0.25mm-1.2mm. If the powder sheet is too thin, its buffering effect on the sound-absorbing particles 40 will be poor; if the powder sheet is too thick, it will occupy more space in the acoustic cavity 30, resulting in a smaller number of sound-absorbing particles 40 filling the acoustic cavity 30.

[0056] According to one embodiment of this application, as shown in Figures 1 to 3, the housing 10 has an opening opposite to the speaker unit 20, and a steel sheet 13 is disposed in the opening. The steel sheet 13, the housing 10 and the speaker unit 20 surround and form a sound cavity 30. The inner wall of the steel sheet 13 forms a steel sheet attachment area, and the inner wall of the housing 10 located on the same plane as the steel sheet 13 forms a first plastic attachment area. The inner wall of the housing 10 opposite to the first plastic attachment area forms a second plastic attachment area.

[0057] Specifically, as shown in Figure 1, the upper cover 11 has an opening, and the opening area is vertically opposite to the speaker unit 20 set on the lower cover 12. The steel sheet 13 is placed in the opening to seal it. Under the dual requirements of space and strength, the housing 10 usually adopts a combination of plastic and steel sheet materials to improve structural strength and increase cavity space.

[0058] In one embodiment, as shown in FIG1, an acoustic reinforcement sheet 50 is attached and fixed on the steel sheet attachment area. The acoustic reinforcement sheet 50 (powder sheet) is attached to the inner side of the steel sheet 13 on the housing 10. When the speaker 60 is working, the moving sound-absorbing particles 40 no longer strike the steel sheet 13 and produce noise.

[0059] In another embodiment, as shown in FIG2, acoustic reinforcement sheets 50 are adhered and fixed on the first plastic attachment area and the second plastic attachment area. The acoustic reinforcement sheets 50 (powder sheets) are attached to the inner side of the plastic housing 10, so that when the speaker 60 is working, the moving sound-absorbing particles 40 no longer impact the housing 10 and produce noise.

[0060] In another embodiment, as shown in FIG3, acoustic reinforcement sheets 50 are attached and fixed to the steel sheet attachment area, the first plastic attachment area, and the second plastic attachment area. Acoustic reinforcement sheets 50 (powder sheets) are attached to the inner side of the steel sheet 13 and the inner side of the plastic housing 10. When the speaker 60 is working, the moving sound-absorbing particles 40 no longer collide with the housing 10 and the steel sheet 13 to produce noise.

[0061] In another embodiment, a speaker unit attachment area is formed on the back side of the speaker unit 20 facing the acoustic cavity 30, and an acoustic reinforcement sheet 50 is attached and fixed to the speaker unit attachment area. With the acoustic reinforcement sheet 50 (powder sheet) attached to the back side of the speaker unit 20, when the speaker 60 is working, the moving sound-absorbing particles 40 no longer collide with the speaker unit 20 and generate noise.

[0062] Implementation Method Two:

[0063] This application also provides a loudspeaker 60, which includes a housing 10 and a loudspeaker unit 20 fixed on the housing 10. The housing 10 and the loudspeaker unit 20 surround and form a sound cavity 30. The sound cavity 30 is filled with sound-absorbing particles 40 and has a noise reduction structure as described in Embodiment 1.

[0064] The loudspeaker 60 described in this application is provided with an acoustic enhancement sheet 50 that can prevent the sound-absorbing particles 40 from colliding with the inner wall of the acoustic cavity 30. No noise generated by the collision of the sound-absorbing particles 40 will be produced in the loudspeaker 60. Moreover, the acoustic enhancement sheet 50 has a sound-absorbing effect and can improve the acoustic enhancement effect of the acoustic cavity 30 in the loudspeaker 60. The setting of the acoustic enhancement sheet 50 has little impact on the sound-absorbing particles 40 in the acoustic cavity 30.

[0065] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely specific embodiments of this application and are not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A structure for reducing noise within a loudspeaker, disposed within a acoustic cavity (30) formed by at least a housing (10) of a loudspeaker (60) and a loudspeaker unit (20) fixed to the housing (10), wherein the acoustic cavity (30) is filled with sound-absorbing particles (40), wherein, The noise reduction structure within the loudspeaker (60) includes: An acoustic enhancement sheet (50) for improving the sound absorption performance of the acoustic cavity (30) is provided inside the acoustic cavity (30). The acoustic enhancement sheet (50) is provided on part or all of the inner wall of the acoustic cavity (30) to avoid collision between the sound-absorbing particles (40) and the inner wall of the acoustic cavity (30). The hardness of the acoustic enhancement sheet (50) is less than the hardness of the inner wall of the acoustic cavity (30). The acoustic enhancement sheet (50) is a powder sheet containing zeolite material.

2. The noise reduction structure within the loudspeaker according to claim 1, wherein, The acoustic enhancement sheet (50) is bonded and fixed to the inner wall of the acoustic cavity (30).

3. The noise reduction structure within the loudspeaker according to claim 1, wherein, The acoustic enhancement plate (50) is disposed on the inner wall of the housing (10), and / or the acoustic enhancement plate (50) is disposed on the back of the speaker unit (20) facing the acoustic cavity (30).

4. The noise reduction structure within the loudspeaker according to claim 1, wherein, The thickness of the powder sheet is 0.1mm-2mm.

5. The noise reduction structure within the loudspeaker according to claim 1, wherein, The housing (10) has an opening opposite to the speaker unit (20), and a steel sheet (13) is provided in the opening. The steel sheet (13), the housing (10) and the speaker unit (20) surround and form the acoustic cavity (30). The inner wall of the steel sheet (13) forms a steel sheet attachment area, and the inner wall of the housing (10) located on the same plane as the steel sheet (13) forms a first plastic attachment area. The inner wall of the housing (10) opposite to the first plastic attachment area forms a second plastic attachment area.

6. The noise reduction structure within the loudspeaker according to claim 5, wherein, The acoustic reinforcement sheet (50) is attached and fixed to the steel sheet attachment area.

7. The noise reduction structure within the loudspeaker according to claim 5, wherein, The acoustic reinforcement sheet (50) is attached and fixed on the first plastic attachment area and / or the second plastic attachment area.

8. The noise reduction structure within the loudspeaker according to claim 5, wherein, The acoustic reinforcement sheet (50) is attached and fixed to the steel sheet attachment area, the first plastic attachment area and the second plastic attachment area.

9. The noise reduction structure within the loudspeaker according to claim 1 or 5, wherein, The speaker unit (20) has a speaker unit attachment area on its back side facing the acoustic cavity (30), and the acoustic reinforcement sheet (50) is attached and fixed on the speaker unit attachment area.

10. A loudspeaker, wherein, The loudspeaker (60) includes a housing (10) and a loudspeaker unit (20) fixed on the housing (10). The housing (10) and the loudspeaker unit (20) surround and form a sound cavity (30). The sound cavity (30) is filled with sound-absorbing particles (40). The sound cavity (30) is provided with a structure for reducing noise in the loudspeaker (60) as described in any one of claims 1-9.

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