Loudspeaker

Abstract

The embodiment of the specification provides a loudspeaker. The loudspeaker comprises a vibrating diaphragm, a shell and a cavity structure. The diaphragm may vibrate to generate an air-guided acoustic wave. The shell can form an accommodating cavity used for accommodating the vibrating diaphragm. The diaphragm can separate the accommodating cavity to form a front cavity and a rear cavity. The shell is provided with a sound outlet hole communicated with the front cavity, and at least part of the air guide sound waves are transmitted to the outside of the loudspeaker through the sound outlet hole. The shell is provided with a cavity structure, and the cavity structure is communicated with at least one of the front cavity and the rear cavity. And the cavity structure is used for absorbing sound waves with target frequency in the air-guided sound waves.

Description

speaker Technical Field

[0001] The present invention relates to the field of acoustic devices, and in particular to a loudspeaker with a cavity structure provided on a shell. Background Art

[0002] With the continuous development of electronic devices, acoustic output devices (such as headphones) have become indispensable social and entertainment tools in people's daily lives, and people's requirements for acoustic output devices are becoming increasingly higher. However, existing acoustic output devices still have many problems, such as complex structures and poor sound quality. Therefore, it is desirable to provide an acoustic output device with a simple structure and high acoustic performance to meet user needs.

[0003] Summary of the Invention

[0004] One of the embodiments of the present specification provides a high-performance loudspeaker, comprising: a diaphragm, which vibrates to generate air-conducted sound waves; and a shell, which forms a housing cavity for accommodating the diaphragm, the diaphragm separating the housing cavity to form a front cavity and a rear cavity, the shell being provided with a sound outlet hole connected to the front cavity, at least part of the air-conducted sound waves being transmitted to the outside of the loudspeaker through the sound outlet hole, wherein a cavity structure is provided on the shell, the cavity structure being connected to at least one cavity of the front cavity and the rear cavity, and the cavity structure being used to absorb sound waves of a target frequency in the air-conducted sound waves.

[0005] In some embodiments, the vibration of the diaphragm has an original resonant frequency, and the difference between the original resonant frequency and the target frequency is within 300 Hz.

[0006] In some embodiments, the target frequency is in the range of 3 kHz-20 kHz.

[0007] In some embodiments, the front cavity is connected to the sound outlet through a sound guiding channel, and the cavity structure is connected to the sound guiding channel through the front cavity.

[0008] In some embodiments, the shell includes a front cavity plate, a rear cavity plate and a side plate, and the cavity structure includes a connecting hole and a sound-absorbing cavity.

[0009] In some embodiments, the communicating hole is connected to the sound absorbing cavity through a sound guiding tube.

[0010] In some embodiments, the equivalent diameter of the sound guide tube is not less than 0.05 mm.

[0011] In some embodiments, the equivalent diameter of the communicating hole is not less than 0.1 mm.

[0012] In some embodiments, the parameter θ ranges from 1000 (1 / m 2 )-40000(1 / m 2 ),in: Wherein, S is the transverse area of ​​the communicating hole, l is the length of the communicating hole, and V is the volume of the sound absorbing cavity.

[0013] In some embodiments, the cavity structure is disposed in the rear cavity plate, and the rear cavity plate includes a cavity front wall, a cavity side wall, and a back plate constituting the cavity structure.

[0014] In some embodiments, the back plate is a damping mesh.

[0015] In some embodiments, sound absorbing material is provided on the back panel.

[0016] In some embodiments, the front wall of the cavity is a damping mesh.

[0017] In some embodiments, the communication hole is located within a projection of the diaphragm along its vibration direction.

[0018] In some embodiments, the diaphragm includes a folding ring portion and a fixed end, and the communication hole faces the folding ring portion of the diaphragm.

[0019] In some embodiments, the speaker further includes a driving unit, which generates vibration based on an electrical signal and drives the diaphragm to vibrate.

[0020] In some embodiments, the driving unit is disposed in the rear cavity, and the driving unit cooperates with the rear cavity plate to divide the rear cavity into a first rear cavity and a second rear cavity, wherein the second rear cavity is composed of the driving unit and the rear cavity plate.

[0021] In some embodiments, the cavity structure is in communication with the first rear cavity but not in communication with the second rear cavity.

[0022] In some embodiments, the cavity structure is in communication with the first rear cavity and with the second rear cavity.

[0023] In some embodiments, the cavity structure includes at least two cavity structures, wherein part of the cavity structure is connected to the first rear cavity but not to the second rear cavity, and the remaining part of the cavity structure is connected to the first rear cavity and to the second rear cavity.

[0024] In some embodiments, the cavity structure is disposed in the front cavity plate.

[0025] In some embodiments, the cavity structure includes at least two cavity structures, and the at least two cavity structures are symmetrically distributed around the central axis of the speaker.

[0026] In some embodiments, the at least two cavity structures absorb sound waves of different frequencies in the air-conducted sound waves. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] This specification will be further described in the form of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting, and in these embodiments, like numbers represent like structures, wherein:

[0028] FIG1 is a block diagram of an exemplary speaker according to some embodiments of the present specification;

[0029] FIG2A is a schematic diagram of the mechanical structure of an exemplary loudspeaker according to some embodiments of this specification;

[0030] FIG2B is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification;

[0031] FIG3 is a frequency response curve of an exemplary speaker according to some embodiments of the present specification;

[0032] FIG4A is a schematic diagram of a three-dimensional structure of an exemplary cavity structure according to some embodiments of this specification;

[0033] FIG4B is a schematic BB cross-sectional view of the cavity structure in FIG4A ;

[0034] FIG4C is a schematic diagram of the AA cross-section of the cavity structure in FIG4A ;

[0035] FIG4D is a schematic diagram showing the cavity volume marked in the cavity structure of FIG4A ;

[0036] FIG5 is a frequency response curve of an exemplary speaker according to some embodiments of the present specification;

[0037] FIG6 is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification;

[0038] 7A-7C are exemplary CC cross-sectional schematic diagrams of the cavity structure in FIG6 ;

[0039] FIG8 is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification;

[0040] FIG9 is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification;

[0041] FIG10 is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification;

[0042] FIG11 is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification;

[0043] FIG12 is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification;

[0044] FIG13 is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification;

[0045] FIG14A is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification;

[0046] FIG14B is a CC cross-sectional view of the cavity structure in FIG14A ;

[0047] FIG15A is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification;

[0048] FIG15B is a CC cross-sectional schematic diagram of the cavity structure in FIG15A . DETAILED DESCRIPTION

[0049] To more clearly illustrate the technical solutions of the embodiments of this application, the following is a brief introduction to the drawings required for describing the embodiments. Obviously, the drawings described below are merely examples or embodiments of this application. Those skilled in the art can apply this application to other similar scenarios based on these drawings without inventive effort. Unless otherwise apparent from the context or otherwise noted, the same reference numerals in the figures represent the same structure or operation.

[0050] It should be understood that the terms "system," "device," "unit," and / or "module" used herein are a method for distinguishing different components, elements, parts, portions, or assemblies at different levels. However, other terms may be used to replace a term if they achieve the same purpose.

[0051] As used in this application and the claims, unless the context clearly indicates an exception, the words "a," "an," "an," and / or "the" do not specifically refer to the singular and include the plural, unless the context clearly indicates an exception. Generally speaking, the terms "including" and "comprising" only indicate the inclusion of the steps and elements specifically identified, and these steps and elements do not constitute an exclusive list. The method or apparatus may also include other steps or elements. The term "based on" means "based at least in part on." The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment."

[0052] In the description of this specification, it should be understood that the terms "first," "second," "third," "fourth," etc. are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first," "second," "third," or "fourth" may explicitly or implicitly include at least one of such features. In the description of this specification, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0053] In this specification, unless otherwise specified or limited, terms such as "connected" and "fixed" should be interpreted broadly. For example, the term "connected" can refer to a fixed connection, a removable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; and can refer to internal communication between two components or an interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this specification based on the specific circumstances.

[0054] The loudspeaker provided in the embodiments of the present specification may include a diaphragm, a shell and a cavity structure. The diaphragm can vibrate to generate air-conducted sound waves. The shell can form a housing for accommodating the diaphragm. The diaphragm divides the housing to form a front cavity and a rear cavity. The shell is provided with a sound outlet hole connected to the front cavity, and at least part of the air-conducted sound waves is transmitted to the outside of the loudspeaker through the sound outlet hole. The shell is provided with a cavity structure. The cavity structure is connected to at least one cavity in the front cavity and the rear cavity, and the cavity structure is used to absorb sound waves of a target frequency in the air-conducted sound waves. In some embodiments, by setting one or more parameters of the cavity structure (for example, shape, position, size, etc.), the target frequency can be set at a specific frequency position, thereby making the frequency response curve of the loudspeaker flatter, thereby improving the acoustic performance of the loudspeaker. In addition, by setting the cavity structure, the mechanical vibration state of the vibration system in the loudspeaker can be affected, thereby adjusting the frequency response curve of the loudspeaker, and achieving the effect of the speaker's own structural filtering.

[0055] The speaker provided in the embodiments of this specification is described in detail below with reference to the accompanying drawings.

[0056] FIG1 is a block diagram of an exemplary loudspeaker according to some embodiments of the present disclosure. As shown in FIG1 , the loudspeaker 100 may include a diaphragm 110 , a housing 120 , and a cavity structure 130 .

[0057] The diaphragm 110 can vibrate to generate air-conducted sound waves. In some embodiments, the diaphragm 110 can directly receive an electrical signal and convert the electrical signal into a vibration signal. For example, the diaphragm 110 may include a piezoelectric diaphragm, an electrostatic driving diaphragm, etc. In other words, the diaphragm 110 is also a driving unit. In some embodiments, the speaker 100 may include a driving unit (for example, the driving unit 140 in Figure 2B). The driving unit can receive an electrical signal and convert the electrical signal into a vibration signal. The driving unit can transmit the vibration signal to the diaphragm 110, for example, through a vibration transfer unit, thereby driving the diaphragm 110 to vibrate. In some embodiments, the driving unit may include a moving coil driving unit, a moving iron driving unit, an electrostatic driving unit, a piezoelectric driving unit, etc. For ease of description, this application will be described in a manner where the diaphragm and the driving unit are independently arranged, which does not limit the scope of this application.

[0058] The housing 120 may form a housing for accommodating other components of the speaker 100 (e.g., the diaphragm 110, the driver, etc.). The diaphragm 110 may separate the housing into a front cavity and a rear cavity. The housing 120 may be provided with a sound outlet hole communicating with the front cavity. At least a portion of the air-conducted sound waves generated by the vibration of the diaphragm 110 may be transmitted to the exterior of the speaker 100 through the sound outlet hole.

[0059] A cavity structure 130 may be provided on the housing 120. The cavity structure 130 may be connected to at least one of the front and rear cavities of the housing 120. The cavity structure 130 may be used to absorb sound waves of a target frequency in the air-conducted sound waves generated by the vibration of the diaphragm 110. In other words, the cavity structure 130 may have a sound-absorbing effect. For more descriptions of the cavity structure 130, please refer to other places in this application (e.g., Figures 2A-2B, 3, 4A-4D, etc. and their descriptions).

[0060] Figure 2A is a schematic diagram of the mechanical structure of an exemplary loudspeaker according to some embodiments of the present specification. Figure 2B is a schematic diagram of the structure of an exemplary loudspeaker according to some embodiments of the present specification.

[0061] As shown in Figures 2A and 2B, the speaker 100 may include a diaphragm 110, a housing 120, a cavity structure 130, a drive unit 140, and a vibration transfer unit 170. The housing 120 may form a receiving cavity for accommodating one or more components of the speaker 100 (for example, the diaphragm 110, the drive unit 140, etc.). The diaphragm 110 may separate the receiving cavity to form a front cavity 150 and a rear cavity 160. The drive unit 140 may perform energy conversion, converting electrical energy (i.e., electrical signal) into mechanical energy (i.e., vibration signal), and transfer the generated mechanical energy to the diaphragm 110 through the vibration transfer unit 170. Driven by the drive unit 140, the diaphragm 110 may vibrate and push the air to generate air-conducted sound waves. At least part of the air-conducted sound waves may be transmitted to the outside of the speaker 100 through a sound outlet (not shown).

[0062] In some embodiments, the housing 120 may include a front cavity plate 122, a rear cavity plate 124, and a side plate 126. The front cavity plate 122, the rear cavity plate 124, and the side plate 126 collectively form the aforementioned accommodating cavity. In some embodiments, the front cavity plate 122, the rear cavity plate 124, and / or the side plate 126 may include a printed circuit board (PCB), a plastic plate, a metal plate, etc., which is not limited in this application.

[0063] In some embodiments, as shown in FIG2B , the drive unit 140 can be disposed in the rear cavity 160 . In some embodiments, the rear cavity 160 can be divided or not divided by setting the arrangement position of the drive unit 140 . For example, for a piezoelectric speaker, the drive unit 140 can be fixed to the speaker housing 120 (e.g., the rear cavity plate 124 ) via a bracket with holes, thereby not dividing the rear cavity 160 . For another example, for an electromagnetic speaker, its magnetic circuit portion (i.e., the drive unit 140 ) can be fixed to the housing 120 (e.g., the rear cavity plate 124 ) via a bracket with holes, thereby not dividing the rear cavity 160 . For another example, as shown in FIG2B , the drive unit 140 can be fixed to the rear cavity plate 124 and cooperate with the rear cavity plate 124 to divide the rear cavity 160 into a first rear cavity 162 and a second rear cavity 164. The first rear cavity 162 can be surrounded by at least a portion of the housing 120 , the drive unit 140 , and the vibration transmission unit 170 . The second rear cavity 164 can be enclosed by the drive unit 140 and the rear cavity plate 124. The second rear cavity 164 can be connected to the exterior of the speaker 100 or not. For ease of description, this application will use the arrangement in which the drive unit 140 can divide the rear cavity 160 as an example, which does not limit the scope of this application.

[0064] The cavity structure 130 may include a sound-absorbing cavity 132 and a communication hole 134. In some embodiments, the cavity structure 130 may be disposed on the front cavity panel 122, the rear cavity panel 124, the side panel 126, or the like. For example, the cavity structure 130 may communicate with the rear cavity 160. The cavity structure 130 may be disposed on the rear cavity panel 124. By adjusting the parameters of the cavity structure 130 (e.g., shape, position, size, etc.), the frequency response curve of the speaker 100 may be adjusted.

[0065] For example, as shown in FIG2A , each component of the loudspeaker 100 can be equivalent to a spring-mass-damper system. Specifically, the diaphragm 110 and the driver 140 are connected via an equivalent spring-damper system (i.e., spring (Kp)-damper (Rp)). Due to the presence of air in the front cavity 150 and the rear cavity 160, the air spring (Ka1)-mass (Ma1)-damper (Ra1) system formed by the first rear cavity 162 and the spring (Ka2)-mass (Ma2)-damper (Ra2) system formed by the second rear cavity 164 can act on the diaphragm 110 (which can be equivalent to a spring (Km)-mass (Mm)-damper (Rm) system) and the driver 140 (which can be equivalent to a spring (Kd)-mass (Md)-damper (Rd) system). The front cavity 150 can be equivalent to a spring (Ka3)-mass (Ma3)-damper (Ra3) system acting on the diaphragm 110.

[0066] In the absence of the cavity structure 130, due to the smaller volume of the first rear cavity 162, the stiffness of the spring (Ka1) in the air spring (Ka1)-mass (Ma1)-damper (Ra1) system of the first rear cavity 162 is greater than the stiffness of the spring (Km) in the spring (Km)-mass (Mm)-damper (Rm) system of the diaphragm 110 and the stiffness of the spring (Kd) in the spring (Kd)-mass (Md)-damper (Rd) system of the driver unit 140. The first rear cavity 162 acts on the diaphragm 110 and the driver unit 140 in the form of additional stiffness, which can reduce the vibration displacement of the diaphragm 110 and the driver unit 140, thereby reducing the output of the speaker. Therefore, by designing the cavity structure 130 and adjusting the resonant frequency of the spring-mass-damper system corresponding to the cavity structure 130, the frequency response curve of the speaker can be adjusted, thereby improving the acoustic output of the speaker.

[0067] Specifically, by designing a cavity structure 130 inside the speaker 100, due to the presence of air, the cavity structure 130 can form a new air spring (Kr)-mass (Mr)-damping (Rr) system. The air spring (Kr)-mass (Mr)-damping (Rr) system can resonate at its resonant frequency. Furthermore, since the cavity structure 130 is a closed cavity, it only generates a large sound pressure in the sound absorption cavity 132 when it resonates, and at the same time, the sound pressure cannot be radiated outward to act on the diaphragm 110, so that the sound pressure radiated outward through the diaphragm 110 is reduced, which is reflected as a trough on the frequency response curve of the speaker 100 (the trough A in the curve 320 shown in Figure 3), thereby achieving the adjustment of the frequency response curve of the speaker 100. In some embodiments of the present application, the frequency corresponding to the trough may also be equal to the target frequency.

[0068] In some embodiments, the target frequency (e.g., the location of the trough) can be adjusted by adjusting one or more parameters of the cavity structure 130 (e.g., shape, position, size, etc.), thereby achieving troughs in different frequency bands on the frequency response curve of the speaker 100, thereby enabling the speaker 100 to meet actual needs and enhance the user experience. For more detailed descriptions of the cavity structure 130, please refer to Figures 4A-4D of this specification and their descriptions, which will not be repeated here.

[0069] FIG3 is a frequency response curve of an exemplary speaker according to some embodiments of this specification. As shown in FIG3 , curve 310 represents the frequency response curve of a speaker without a cavity structure. Curve 320 represents the frequency response curve of a speaker with a cavity structure (such as speaker 100).

[0070] As can be seen from Figure 3, for a loudspeaker without a cavity structure, the vibration of its diaphragm can have a corresponding resonant frequency (the frequency corresponding to the resonant peak B of the frequency response curve 310). Due to the existence of the resonant frequency of the diaphragm vibration, the frequency response curve of the loudspeaker without a cavity structure is not flat enough. By providing a cavity structure (for example, the cavity structure 130) on the loudspeaker housing (for example, the front cavity plate 122 or the rear cavity plate 124 of the housing 120), the response of the loudspeaker's frequency response curve at the target frequency position can be reduced due to the sound absorption effect of the cavity structure on the target frequency sound waves. As shown in Figure 3, setting the sound absorption frequency of the cavity structure (i.e., the target frequency) at the resonant frequency of the diaphragm vibration can effectively suppress the peak value of the diaphragm vibration at this frequency, and can even cause the overall frequency response curve of the loudspeaker to produce a trough at the resonant frequency of the diaphragm vibration.

[0071] As an example only, for a loudspeaker with a cavity structure, the vibration of its diaphragm may have a corresponding original resonant frequency (which may be approximately the frequency corresponding to the resonance peak B of the frequency response curve 310). In some embodiments, by designing the parameters of the cavity structure (e.g., shape, position, size, etc.), the target frequency of the cavity structure may be near the original resonant frequency of the diaphragm vibration, thereby significantly reducing the peak value of the loudspeaker with the cavity structure at the original resonant frequency, forming a trough, and having two peaks on both sides of the trough, both of which are smaller than the peak value at the original resonant frequency (e.g., peak C and peak D in FIG3 , wherein the amplitudes corresponding to peak C and peak D are both smaller than the amplitude of the resonance peak B, and the amplitude difference between peak C or peak D and the resonance peak B may be greater than 6 dB, and the amplitude difference between valley A and the resonance peak B may be greater than 12 dB), thereby improving the overall sensitivity of the loudspeaker and making the loudspeaker frequency response curve flatter. In some embodiments, the difference between the target frequency and the original resonant frequency may be within 300 Hz. Preferably, the difference between the target frequency and the original resonant frequency may be within 200 Hz. More preferably, the difference between the target frequency and the original resonant frequency may be within 100 Hz. More preferably, the target frequency may be equal to the original resonant frequency.

[0072] In some embodiments, the frequency response curve of the speaker is usually relatively smooth in the mid-low frequency band, while the mid-high frequency band is affected by the high-order modes of the speaker diaphragm and the drive unit, as well as the modes of the cavity, which will form more resonance peaks. Therefore, in order to make the frequency response curve of the speaker smoother in the mid-high frequency band, the corresponding cavity structure can be designed so that its target frequency is in the mid-high frequency band. In some embodiments, the target frequency can be in the range of 1kHz-20kHz. In some embodiments, the target frequency can be in the range of 3kHz-20kHz. In some embodiments, the target frequency can be in the range of 3kHz-10kHz. In some embodiments, the target frequency can be in the range of 3kHz-8kHz.

[0073] As shown in Figure 3, a speaker with a cavity structure has a flatter frequency response curve than a speaker without a cavity structure, resulting in a better acoustic effect. In some embodiments, the depth of the trough can be adjusted by adjusting the damping of one or more components of the speaker (e.g., cavity structure 130), making the speaker's frequency response curve even flatter, thereby further improving the speaker's acoustic effect.

[0074] Figure 4A is a schematic diagram of a three-dimensional structure of an exemplary cavity structure according to some embodiments of this specification. Figure 4B is a schematic diagram of a BB cross-section of the cavity structure in Figure 4A. Figure 4C is a schematic diagram of an AA cross-section of the cavity structure in Figure 4A. Figure 4D is a schematic diagram of the cavity structure in Figure 4A with the cavity volume marked.

[0075] In some embodiments, as shown in FIG4A , the cavity structure 130 may include a sound absorbing cavity 132 and a communication hole 134. By designing the dimensions (e.g., the dimensions of the sound absorbing cavity 132 and the dimensions of the communication hole 134) and the shape of the cavity structure 130, sound absorption effects can be achieved in different frequency bands, thereby achieving a valley effect at different locations on the frequency response curve of the speaker 100.

[0076] In some embodiments, as shown in FIG. 4B to FIG. 4D , the equivalent diameter of the communication hole 134 is The length of the connecting hole 134 is l, the transverse area of ​​the connecting hole 134 is S, and the volume of the sound absorption cavity 132 is V. The position (or target frequency) of the valley formed by the cavity structure 130 can be adjusted by adjusting the value range of the parameter θ, thereby adjusting the acoustic output of the speaker. The parameter θ can be determined according to the following formula (1):

[0077]

[0078] The larger the parameter θ value corresponding to the cavity structure 130 is, the larger the corresponding target frequency is. In some embodiments, in order to make the valley position be between 1kHz and 20kHz, the value range of the parameter θ can be 1000 (1 / m 2 )-40000(1 / m 2 In some embodiments, in order to make the valley position be between 2kHz and 10kHz, the value range of the parameter θ can be 2000 (1 / m 2 )-35000(1 / m 2 ).

[0079] In some embodiments, the equivalent diameter of the communication hole 134 is The size of will affect the acoustic resistance, thereby affecting the valley formed by the cavity structure 130. For example, A value that is too small will result in a large acoustic resistance, making the cavity structure 130 unable to achieve the sound absorption effect. In some embodiments, to ensure that the cavity structure 130 has a sound absorption effect, the equivalent diameter of the connecting hole 134 can be no less than 0.05 mm. Preferably, the equivalent diameter of the connecting hole 134 can be no less than 0.1 mm.

[0080] FIG5 is a frequency response curve of an exemplary loudspeaker according to some embodiments of the present disclosure. As shown in FIG5 , curve 510 represents the frequency response curve of a loudspeaker without a cavity structure. Curve 520 represents the frequency response curve of a loudspeaker with a cavity structure and parameter θ=2500 (1 / m 2 ) of the speaker. Curve 530 represents the frequency response curve of the speaker with a cavity structure and parameter θ = 30000 (1 / m 2 ) of the speaker's frequency response curve.

[0081] As can be seen from FIG5 , compared to a speaker without a cavity structure (corresponding to curve 510 ), by providing the cavity structure 130 in the speaker housing 120 (corresponding to curves 520 or 530 ), a trough can be formed at a specific frequency, while two peaks are formed on the left and right sides of the trough, thereby improving the sensitivity of the speaker. Furthermore, by adjusting one or more parameters of the cavity structure, the trough (or target frequency) can be positioned at different locations. For example, by adjusting the value of the cavity structure parameter θ, troughs can be formed near 2.2 kHz on curve 520 and near 8 kHz on curve 530 , respectively.

[0082] FIG6 is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification.

[0083] In some embodiments, as shown in FIG6 , the cavity structure 130 may further include a sound guide tube 136. The connecting hole 134 may be connected to the sound absorption cavity 132 via the sound guide tube 136. By providing the sound guide tube 136, the configuration of the cavity structure 130 may be made more flexible. For example, by providing the sound guide tube 136, the sound absorption cavity 132 may be separated from the connecting hole 134. For example, the sound absorption cavity 132 may be provided on the rear cavity plate 124, and the connecting hole 134 may be provided on the side plate 126. The sound absorption cavity 132 and the connecting hole 134 may then be connected via the sound guide tube 136, thereby adjusting the frequency response of the speaker. In some embodiments, in order for the cavity structure 130 to achieve a sound absorption effect, the equivalent diameter of the sound guide tube 136 may be no less than 0.05 mm. Preferably, the equivalent diameter of the sound guide tube 136 may be no less than 0.1 mm.

[0084] Figures 7A-7C are exemplary CC cross-sectional views of the cavity structure in Figure 6 . In some embodiments, the specific shapes of the sound absorption cavity 132, communication holes 134, and / or sound conduit 136 included in cavity structure 130 can be configured based on the actual space size. In some embodiments, as shown in Figures 7A-7C , the sound absorption cavity 132, communication holes 134, and / or sound conduit 136 can be square, circular, elliptical, polygonal, or other irregular shapes, or a combination thereof.

[0085] FIG8 is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification.

[0086] In some embodiments, as shown in FIG8 , the cavity structure 130 can be disposed on the front cavity plate 122 . The cavity structure 130 can be connected to the front cavity 150 via a connecting hole 134 . By designing the cavity structure 130 in the front cavity plate 122 , the cavity structure 130 can not only affect the vibration state of the speaker vibration system, but can also directly absorb part of the air-conducted sound waves generated by the vibration of the diaphragm 110 , thereby affecting the acoustic performance of the speaker 100 . In this specification, direct absorption can refer to the effect of the cavity structure 130 on the air-conducted sound waves generated by the speaker during the transmission to the sound outlet due to the connection between the cavity structure 130 and the front cavity 150 . Compared to the rear cavity plate 124 , by designing the cavity structure 130 on the front cavity plate 122 , its design is simpler and more convenient, and also facilitates subsequent assembly. In some embodiments, the front cavity 150 can be connected to the sound outlet via a sound-conducting channel (not shown). The cavity structure 130 can be connected to the sound-conducting channel through the front cavity 150. In other words, the cavity structure 130 is connected to the sound outlet through the front cavity 150 and the sound guide channel.

[0087] FIG9 is a schematic structural diagram of an exemplary speaker according to some embodiments of the present specification.

[0088] In some embodiments, as shown in FIG9 , the front cavity 150 of the speaker housing 120 can be connected to the sound outlet 190 through the sound guiding channel 180. The cavity structure 130 can also be arranged in the sound guiding channel 180, that is, the cavity structure 130 can be connected to the front cavity 150 through the sound guiding channel 180. In other words, the cavity structure 130 is connected to the sound outlet only through the sound guiding channel. By designing the cavity structure 130 in the wall of the sound guiding channel 180, its design is simpler and more convenient, and it is also convenient for subsequent assembly. For example, different sound guiding channels with different cavity structures can be used as accessories, and components other than the sound guiding channels equipped with cavity structures can be used as basic components. For the same basic component, different accessories can be assembled on it to achieve different adjustments to the frequency response of the speaker, so that the speaker can adapt to different application scenarios.

[0089] FIG10 is a schematic structural diagram of an exemplary speaker according to some embodiments of this specification.

[0090] In some embodiments, as shown in Figure 10, the driver unit 140 can cooperate with the rear cavity plate 124 to isolate the second rear cavity 164 from the outside of the speaker. Specifically, the rear cavity plate 124 can have a groove structure, and the driver unit 140 can be mounted above the groove, so that the second rear cavity 164 enclosed by the driver unit 140 and the rear cavity plate 124 is isolated from the outside.

[0091] In some embodiments, the speaker 100 may include at least two cavity structures 130. The at least two cavity structures 130 can be used to absorb air-conducted sound waves of the same or different frequencies in the air-conducted sound waves. In other words, the at least two cavity structures 130 can correspond to the same or different target frequencies. For example, the target frequencies corresponding to the at least two cavity structures 130 can respectively correspond to the frequencies corresponding to the high-order modes of the diaphragm 110 and the drive unit 140, so that the speaker 100 has a relatively flat frequency response in a higher frequency band (for example, 3kHz-10kHz), thereby improving the acoustic output effect of the speaker.

[0092] In some embodiments, at least two cavity structures 130 can be disposed at different locations on the speaker 100. For example, at least two cavity structures 130 can be disposed on the rear cavity panel 124. For another example, one cavity structure 130 can be disposed on the rear cavity panel 124, while the remaining cavity structures 130 can be disposed on the front cavity panel 122. For another example, one cavity structure 130 can be disposed on the wall of the sound guide channel, one cavity structure 130 can be disposed on the front cavity panel 122, while the remaining cavity structures 130 can be disposed on the rear cavity panel 124.

[0093] In some embodiments, when at least two cavity structures 130 are arranged on the rear cavity plate 124, if the cavity structure 130 is arranged at a local position on the rear cavity plate 124, the cavity structure 130 can locally affect the motion state of the diaphragm 110, resulting in an imbalance in the air stiffness in the rear cavity 160 (for example, the first rear cavity 162), thereby causing the diaphragm 110 to tilt, resulting in a resonance peak of a high-order mode on the speaker's frequency response curve, and reducing the speaker's acoustic output. Therefore, to avoid unnecessary high-order modes in the speaker 100, the at least two cavity structures 130 can be symmetrically (or approximately symmetrically) distributed about the central axis of the speaker 100 (for example, the center point of the sound absorption cavity is symmetrically distributed about the central axis of the speaker 100). In addition, by arranging the at least two cavity structures 130 symmetrically about the central axis of the speaker 100, the structure of the rear cavity plate 124 (or the front cavity plate 122) can be made more reliable, thereby extending the life of the speaker. For example, as shown in Figure 10, the speaker 100 can include two cavity structures 130. The two cavity structures 130 may be located on either side of the central axis of the speaker 100. Furthermore, the two cavity structures 130 may be symmetrically arranged in the rear cavity plate 124 around the central axis of the speaker 100. Both cavity structures 130 are connected only to the first rear cavity 162 but not to the second rear cavity 164.

[0094] FIG11 is a schematic structural diagram of an exemplary speaker according to some embodiments of the present specification.

[0095] In some embodiments, at least one of the at least two cavity structures 130 can be connected to the first rear cavity 162 and the second cavity 164. By connecting the second rear cavity 164 with the sound absorption cavity 132 of at least one cavity structure 130, the size of the sound absorption cavity 132 of the cavity structure 130 can be adjusted, while increasing the adjustable range of the target frequency corresponding to the cavity structure 130, thereby improving the adaptability of the speaker 100. In addition, the sound absorption cavity 132 of the cavity structure 130 is directly connected to the second rear cavity 164. The equivalent air spring mass damping system of the cavity structure 130 can act directly on the driver unit 140, thereby adjusting the vibration effect of the driver unit 140 and achieving the effect of self-filtering of the speaker. For example, as shown in Figure 11, the left cavity structure 130 is connected to both the first rear cavity 162 and the second rear cavity 164, while the right cavity structure 130 is connected only to the first rear cavity 162. In some alternative embodiments, the cavity structure 130 on the right may also be connected to the second rear cavity 164 . In this case, at least one cavity structure 130 may be connected to each other through the second rear cavity 164 , further increasing the size of the sound absorption cavity 132 .

[0096] FIG12 is a schematic structural diagram of an exemplary speaker according to some embodiments of the present specification.

[0097] In some embodiments, as shown in FIG12 , the rear cavity panel 124 may include a cavity front wall 1241, cavity side walls 1242, and a back panel 1243, which constitute the cavity structure 130. In some embodiments, the target frequency of the cavity structure 130 can be further adjusted by adjusting the materials of the cavity front wall 1241, cavity side walls 1242, and / or back panel 1243 of the cavity structure 130. For example, as shown in FIG12 , the back panel 1243 may be a damping mesh. For another example, as shown in FIG15A , the cavity front wall 1241 may be a damping mesh. The damping mesh has a certain air permeability. When used as a back panel or cavity front wall, it is equivalent to adding an additional sound-absorbing cavity, which can fine-tune the target frequency of the cavity structure 130. Furthermore, the damping mesh can reduce the quality factor (i.e., Q value) of the speaker, thereby reducing the depth of the valley generated by the cavity structure 130 and making the frequency response curve of the speaker 100 flatter.

[0098] FIG13 is a schematic structural diagram of an exemplary speaker according to some embodiments of the present specification.

[0099] In some embodiments, as shown in FIG13 , a sound-absorbing material 1010 may be provided on the back plate 1243. By providing the sound-absorbing material 1010 on the back plate 1243, the bandwidth and Q value of the trough formed by the cavity structure 130 can be adjusted, thereby making the trough formed by the cavity structure 130 shallower and further flattening the frequency response curve of the speaker 100.

[0100] In some embodiments, the sound absorbing material 1010 may include foam sponge (e.g., sound-absorbing cotton), ceramic adsorption particles (e.g., zeolite-based ceramic porous materials), carbon nanotube-based sound absorbing materials, etc. The structure of these sound absorbing materials can absorb and dissipate cavity resonant standing waves, thereby improving the sound quality of the speaker.

[0101] In some embodiments, the sound-absorbing material 1010 may include porous foam, porous beads, or the like. Providing the sound-absorbing material 1010 can increase the virtual volume of the sound-absorbing cavity 132, thereby adjusting the speaker's performance. Furthermore, because the sound-absorbing material 1010 can increase the virtual volume of the sound-absorbing cavity 132, the speaker's size can be further reduced while maintaining the same acoustic output, making the speaker 100 adaptable to a wider range of applications.

[0102] Figure 14A is a schematic diagram of the structure of an exemplary loudspeaker according to some embodiments of the present specification. Figure 14B is a CC cross-sectional diagram of the cavity structure in Figure 14A.

[0103] In some embodiments, as shown in Figures 14A and 14B, the communication hole 134 can be located within the projection of the diaphragm 110 along its vibration direction (i.e., direction ZZ'). In other words, the cavity structure 130 can affect the air near the diaphragm 110 through the communication hole 134. Therefore, the position of the communication hole 134 can be set to affect the local air in different parts of the diaphragm 110, thereby changing the state of the diaphragm 110 and making the diaphragm's vibration more consistent with the speaker's usage requirements.

[0104] In some embodiments, as shown in FIG14A , the diaphragm 110 may include a surround 112 and a fixed end 114. In some embodiments, the communication hole 134 may be located near the surround 112 of the diaphragm 110. For example, the communication hole 134 may be directly opposite the surround 112 of the diaphragm 110. Generally speaking, the stiffness of the diaphragm 110 is lower near the surround 112, while the stiffness is higher near the fixed end 114. Therefore, the closer the communication hole 134 is to the edge of the fixed end 114, the less impact it has on the diaphragm 110; and the closer the communication hole 134 is to the center of the surround 112, the greater its impact on the diaphragm 110. By placing the communication hole 134 near the surround 112, the cavity structure 130 can influence the local air near the surround 112, thereby more easily affecting the vibration state of the diaphragm 110 and facilitating adjustment of the acoustic performance of the speaker 100. In some embodiments, when it is desired that the cavity structure 130 have a smaller effect on the vibration of the diaphragm 110, the communication hole 134 can be disposed near the fixed end 114 of the diaphragm 110. By disposing the communication hole 134 near the fixed end 114, the cavity structure 130 can have a smaller effect on the local air near the fold 112, thereby reducing the impact of the cavity structure 130 on the vibration state of the diaphragm 110 and further fine-tuning the acoustic performance of the speaker 100.

[0105] In some embodiments, as shown in Figures 14A-14B, the projection contour of the connecting hole 134 on the CC section can be located within the projection contour of the cavity structure 130 on the CC section, and the projection contour of the connecting hole 134 does not contact the projection contour of the cavity structure 130, so that the connecting hole 134 of the cavity structure 130 can be set close to the folding ring portion 112 of the diaphragm 110.

[0106] Figure 15A is a schematic diagram of the structure of an exemplary loudspeaker according to some embodiments of the present specification. Figure 15B is a CC cross-sectional diagram of the cavity structure in Figure 15A.

[0107] In some embodiments, as shown in FIG15A , the front wall 1241 of the cavity structure 130 can be a damping mesh. By using damping materials with different acoustic resistance coefficients, the Q value of the cavity structure 130 can be adjusted, making the speaker's frequency response curve smoother to meet the needs of different scenarios. In some embodiments, as shown in FIG15A-15B , the projection of the connecting hole 134 on the CC cross-section can be located within the projection of the sound absorption cavity 132 on the CC cross-section, and the projection of the connecting hole 134 overlaps at least one edge of the projection of the sound absorption cavity 132, thereby allowing the connecting hole 134 of the cavity structure 130 to be positioned close to the fixed end 114 of the diaphragm 110.

[0108] It should be noted that, in some embodiments, the arrangement of the cavity structure on the rear cavity panel described in this specification can also be applied to, or replaced by, the arrangement of the cavity structure on the front cavity panel or side panel. For example, when the cavity structure is arranged on the front cavity panel, the front wall or back panel of the sound absorption cavity can be provided with a damping mesh, or sound-absorbing material can be provided in the sound absorption cavity. For another example, when the cavity structure is arranged on the front cavity panel, its connecting hole can be located near the diaphragm's ring portion.

[0109] The beneficial effects that may be brought about by the embodiments of this specification include but are not limited to: (1) by setting a cavity structure on the speaker housing, a trough is generated on the speaker frequency response curve, so that the speaker directly emits the sound after the adjusted frequency response, achieving the effect of the speaker's own structural filtering; (2) by adjusting the shape, position, size, etc. of the cavity structure, the target frequency corresponding to the cavity structure is made the same or close to the original resonant frequency of the diaphragm, so that the frequency response curve of the speaker is flatter, thereby improving the acoustic performance of the speaker; (3) by setting the cavity structure in the front cavity plate and / or the rear cavity plate, and combining it with a damping net, sound-absorbing material, etc., the frequency response curve of the speaker is further flattened, further improving the acoustic performance of the speaker; (4) by setting multiple cavity structures to be symmetrically (or approximately symmetrically) distributed around the central axis of the speaker, the reliability of the speaker housing is improved and the processing cost of the speaker is reduced. It should be noted that different embodiments may produce different beneficial effects. In different embodiments, the beneficial effects that may be produced may be any one or a combination of the above, or any other possible beneficial effects.

[0110] The basic concepts have been described above. It will be apparent to those skilled in the art that the detailed disclosure above is merely illustrative and does not limit the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and amendments to the present application. Such modifications, improvements, and amendments are suggested in the present application and remain within the spirit and scope of the exemplary embodiments of the present application.

Claims

1. A loudspeaker, comprising: a diaphragm that vibrates to generate air-conducted sound waves; as well as A housing is formed to accommodate the diaphragm, the diaphragm divides the housing to form a front cavity and a rear cavity, and the housing is provided with a sound outlet hole communicating with the front cavity, and at least part of the air-conducted sound waves are transmitted to the outside of the speaker through the sound outlet hole, wherein: The shell is provided with a cavity structure, which is connected to at least one of the front cavity and the rear cavity, and is used to absorb sound waves of target frequency in the air-conducted sound waves.

2. The loudspeaker according to claim 1, wherein The vibration of the diaphragm has an original resonant frequency, and the difference between the original resonant frequency and the target frequency is within 300 Hz.

3. The loudspeaker according to claim 1 or 2, wherein: The target frequency is in the range of 3 kHz to 20 kHz.

4. The loudspeaker according to any one of claims 1 to 3, wherein The front cavity is communicated with the sound outlet through a sound guide channel, and the cavity structure is communicated with the sound guide channel through the front cavity.

5. The loudspeaker according to any one of claims 1 to 4, wherein The shell includes a front cavity plate, a rear cavity plate and a side plate, and the cavity structure includes a communicating hole and a sound absorbing cavity.

6. The loudspeaker according to claim 5, wherein The communicating hole is communicated with the sound absorbing cavity through a sound guiding tube.

7. The loudspeaker according to claim 6, wherein The equivalent diameter of the sound guide tube is not less than 0.05 mm.

8. The loudspeaker according to any one of claims 5 to 7, wherein The equivalent diameter of the communicating hole is not less than 0.1 mm.

9. The loudspeaker according to any one of claims 5 to 8, wherein The value range of parameter θ is 1000(1 / m 2 )-40000(1 / m 2 ),in: Wherein, S is the transverse area of ​​the communicating hole, l is the length of the communicating hole, and V is the volume of the sound absorbing cavity.

10. The loudspeaker according to any one of claims 5 to 9, wherein The cavity structure is arranged in the rear cavity plate, and the rear cavity plate includes a cavity front wall, a cavity side wall and a back plate constituting the cavity structure, wherein the cavity front wall, the cavity side wall and / or the back plate include a damping mesh.

11. The loudspeaker according to any one of claims 5 to 10, wherein: The communication hole is located within the projection of the diaphragm along its vibration direction.

12. The loudspeaker according to any one of claims 5 to 11, wherein The diaphragm includes a folding ring portion and a fixed end, and the communication hole faces the folding ring portion of the diaphragm.

13. The loudspeaker according to any one of claims 5 to 12, wherein The speaker also includes a driving unit, which generates vibration based on an electrical signal and drives the diaphragm to vibrate, wherein the driving unit is arranged in the rear cavity, and the driving unit cooperates with the rear cavity plate to divide the rear cavity into a first rear cavity and a second rear cavity, wherein the second rear cavity is composed of the driving unit and the rear cavity plate.

14. The loudspeaker according to claim 13, wherein The cavity structure is in communication with the first rear cavity but not in communication with the second rear cavity.

15. The loudspeaker according to claim 13, wherein The cavity structure is in communication with the first rear cavity and the second rear cavity.

16. The loudspeaker according to claim 13, wherein The cavity structure includes at least two cavity structures, wherein part of the cavity structure is connected to the first rear cavity but not to the second rear cavity, and the remaining part of the cavity structure is connected to the first rear cavity and the second rear cavity.

17. The loudspeaker according to any one of claims 5 to 9, wherein The cavity structure is arranged in the front cavity plate.

18. The loudspeaker according to any one of claims 1 to 17, wherein The cavity structure includes at least two cavity structures, and the at least two cavity structures are symmetrically distributed around the central axis of the speaker.

19. The loudspeaker according to claim 18, wherein The at least two cavity structures absorb sound waves of the same or different frequencies in the air-conducted sound waves.

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