Bone conduction speaker and earphone

Abstract

To provide a method to improve the sound quality of a bone conduction speaker or a bone conduction earphone that can reduce noise.SOLUTION: The bone conduction speaker includes a drive device 101 that includes a coil and a magnetic system and generates a driving force, a panel 103 that is conductively connected to the drive device 101 and all or a portion of which is in contact with a user's body to make the sound conduct through a conduction component 102, and a housing 104 that accommodates the drive device. Two resonant peaks of the bone conduction speaker are below 500 Hz.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This disclosure claims priority to Chinese Patent Application No. 201810623408.2, filed on June 15, 2018, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates generally to a method for improving the sound quality of a speaker, and more particularly, a bone conduction speaker or a bone conduction earphone. [Background technology]

[0003] Generally, people can hear sounds because sound vibrations are transmitted through the air to the eardrum through the ear canal. The vibrations formed by the eardrum can stimulate the human auditory nerve, allowing the human to perceive the sound vibrations. When a bone conduction speaker is operating, sound vibrations are transmitted through the human skin, subcutaneous tissue, and bone to the human auditory nerve, allowing people to hear sounds. Summary of the Invention

[0004] One embodiment of the present disclosure provides a bone conduction speaker. The bone conduction speaker may include a driver and a panel. The driver may generate a driving force located in a straight line. The panel may be communicably connected to the driver. The panel may conduct sound. An area of ​​the panel that interacts with a user's body may have a normal. The normal may not be parallel to the straight line.

[0005] In some embodiments, the straight line may have a positive direction pointing out of the bone conduction speaker through the panel, the normal may have a positive direction pointing out of the bone conduction speaker, and the angle in the positive direction between the two lines may be an acute angle.

[0006] In some embodiments, the drive device may include a coil and a magnetic system, and the axis of the coil and the axis of the magnetic system may not be parallel to the normal, and the axis may be perpendicular to at least one of the radial plane of the coil and the radial plane of the magnetic system.

[0007] In some embodiments, the bone conduction speaker may further include a housing, which may be connected to the panel via a connection medium, or the housing and the panel may be integrally formed.

[0008] In some embodiments, the coil may be connected to at least one of the panel and the housing via a first transmission path, and the magnetic system may be connected to at least one of the panel and the housing via a second transmission path.

[0009] In some embodiments, the first transmission path may include a connection part, and the second transmission path may include a vibration transmission sheet, and the connection part may have a stiffness greater than the stiffness of the vibration transmission sheet.

[0010] In some embodiments, the stiffness of a component on the first transmission path or the second transmission path may be positively correlated with the elastic modulus and thickness of the component, and negatively correlated with the surface area of ​​the component.

[0011] In some embodiments, stiffeners may be provided on the connecting pieces.

[0012] In some embodiments, the reinforcement may be a facade or support rod.

[0013] In some embodiments, the connecting piece may be a hollow cylinder, one end surface of which may be connected to one end surface of the coil, and the other end surface of which may be connected to at least one of the panel and the housing.

[0014] In some embodiments, the connecting components may be a group of connecting rods, one end of each connecting rod may be connected to one end face of the coil, and the other end of each connecting rod may be connected to at least one of the panel and the housing, and each connecting rod may be arranged circumferentially around the coil.

[0015] In some embodiments, the driving force may have components in at least one of the first and third quadrants of an x-o-y plane coordinate system. The origin o of the x-o-y plane coordinate system may be located on the contact surface of the bone conduction speaker with the user's body. The x-axis may be parallel to the coronal axis of the human body. The y-axis may be parallel to the sagittal axis of the human body. The positive direction of the x-axis may be toward the outside of the user's body. The positive direction of the y-axis may be toward the front of the human body.

[0016] In some embodiments, the number of drivers may be at least 2. The line on which the resultant force of the driving forces generated by each driver lies may not be parallel to the normal.

[0017] In some embodiments, the line on which the first driving force generated by the first driving device lies may be parallel to the normal, and the line on which the second driving force generated by the second driving device lies may be perpendicular to the normal.

[0018] In some embodiments, the area of ​​the panel is 20 mm 2 ~1000mm 2 It may be in the range of

[0019] In some embodiments, the side length of the panel may range from 5 mm to 40 mm, or from 18 mm to 25 mm, or from 11 to 18 mm.

[0020] In some embodiments, an angle may be formed between the normal and the line on which the driving force is located, and the angle may be between 5° and 80°, or between 15° and 70°, or between 25° and 50°, or between 25° and 40°, or between 28° and 35°, or between 27° and 32°, or between 30° and 35°, or between 25° and 60°, or between 28° and 50°, or between 30° and 39°, or between 31° and 38°, or between 32° and 37°, or between 33° and 36°, or between 33° and 35.8°, or between 33.5° and 35°.

[0021] In some embodiments, the angle between the line on which the driving force is located and the normal may be 26°±0.2, 27°±0.2, 28°±0.2, 29°±0.2, 30°±0.2, 31°±0.2, 32°±0.2, 33°±0.2, 34°±0.2, 34.2°±0.2, 35°±0.2, 35.8°±0.2, 36°±0.2, 37°±0.2, or 38°±0.2.

[0022] In some embodiments, the area where the panel interacts with the user's body may be flat.

[0023] In some embodiments, the area where the panel interacts with the user's body may be quasi-planar. The normal to the area may be the average normal of the area. The average normal may be:

number

number

[0024] In some embodiments, the predetermined threshold may be less than 10 degrees.

[0025] Another embodiment of the present disclosure provides another bone conduction speaker. The bone conduction speaker may include a panel and a driver. The panel may be communicatively connected to the driver. The panel may conduct sound. An area of ​​the panel that interacts with a user's body may have a normal. An axis of the driver may not be parallel to the normal. The driver may include a coil and a magnetic system. The axis of the driver may be perpendicular to a radial plane of the coil and / or a radial plane of the magnetic system.

[0026] In some embodiments, the bone conduction speaker may further include a housing, which may be connected to the panel via a connection medium, or the housing and the panel may be integrally formed.

[0027] In some embodiments, the coil may be connected to the panel and / or housing via a connecting piece.

[0028] In some embodiments, stiffeners may be provided on the connecting pieces.

[0029] In some embodiments, the reinforcement may be a facade or support rod.

[0030] In some embodiments, one side of the connecting piece may be shorter than the other side such that the axis of the coil is not parallel to the normal.

[0031] In some embodiments, the connection piece may be a hollow cylinder, one end surface of which may be connected to one end surface of the coil, and the other end surface of which may be connected to the panel and / or the housing.

[0032] In some embodiments, the connecting components may be a group of connecting rods, one end of each connecting rod may be connected to one end face of the coil, and the other end of each connecting rod may be connected to the panel and / or the housing, and each connecting rod may be arranged circumferentially around the coil.

[0033] In some embodiments, the area where the panel interacts with the user's body may be flat.

[0034] In some embodiments, the area where the panel interacts with the user's body may be quasi-planar. The normal to the area may be the average normal of the area. The average normal may be:

number

number

[0035] In some embodiments, the predetermined threshold may be less than 10 degrees.

[0036] In some embodiments, the area of ​​the panel is 20 mm 2 ~1000mm 2 It may be in the range of

[0037] In some embodiments, the side length of the panel may range from 5 mm to 40 mm, or from 18 mm to 25 mm, or from 11 to 18 mm.

[0038] In some embodiments, the axis of the driver may have a positive direction pointing out of the bone conduction speaker through the panel, the normal may have a positive direction pointing out of the bone conduction speaker, and the angle in the positive direction between the two lines may be an acute angle.

[0039] In some embodiments, the angle between the normal and the line on which the driving force is located may be between 5° and 80°, or between 15° and 70°, or between 25° and 50°, or between 25° and 40°, or between 28° and 35°, or between 27° and 32°, or between 30° and 35°, or between 25° and 60°, or between 28° and 50°, or between 30° and 39°, or between 31° and 38°, or between 32° and 37°, or between 33° and 36°, or between 33° and 35.8°, or between 33.5° and 35°.

[0040] In some embodiments, the angle between the line on which the driving force is located and the normal may be 26°±0.2, 27°±0.2, 28°±0.2, 29°±0.2, 30°±0.2, 31°±0.2, 32°±0.2, 33°±0.2, 34°±0.2, 34.2°±0.2, 35°±0.2, 35.8°±0.2, 36°±0.2, 37°±0.2, or 38°±0.2.

[0041] Another embodiment of the present disclosure provides another bone conduction speaker. The bone conduction speaker may include a panel and at least two drivers. The panel may be communicatively connected to each of the two drivers. The panel may conduct sound. A region of the panel that interacts with the user's body may have a normal. An axis of the first driver may be parallel to the normal, and an axis of the second driver may be perpendicular to the normal. The drivers may include a coil and a magnetic system. An axis of the driver may be perpendicular to a radial plane of the coil and / or a radial plane of the magnetic system.

[0042] In some embodiments, the area where the panel interacts with the user's body may be flat.

[0043] In some embodiments, the area where the panel interacts with the user's body may be quasi-planar. The normal to the area may be the average normal of the area. The average normal may be:

number

number

[0044] In some embodiments, the predetermined threshold may be less than 10 degrees.

[0045] Another embodiment of the present disclosure provides a bone conduction earphone, which may include the bone conduction speaker according to any one of the preceding claims.

[0046] Another embodiment of the present disclosure provides a method for installing a bone conduction speaker. The method may include communicatively connecting a panel to a driver. The driver may be located in a straight line. The panel may conduct sound. An area where the panel interacts with a user's body may have a normal. The method also includes installing the driver and the panel relative to each other such that the straight line is not parallel to the normal.

[0047] In some embodiments, the method may include establishing relative positions of the driver and the panel such that the driving force has components in at least one of a first quadrant and a third quadrant of an xoy-plane coordinate system. The origin o of the xoy-plane coordinate system may be located on a surface of the bone conduction speaker that contacts the user's body. The x-axis may be parallel to the coronal axis of the human body. The y-axis may be parallel to the sagittal axis of the human body. The positive direction of the x-axis may be toward the outside of the user's body. The positive direction of the y-axis may be toward the front of the human body.

[0048] In some embodiments, the number of drivers may be at least two, and the method may include positioning each driver relative to the panel such that a line on which a resultant force of the driving forces generated by each driver is located is not parallel to the normal.

[0049] In some embodiments, the area where the panel interacts with the user's body may be flat.

[0050] In some embodiments, the area where the panel interacts with the user's body may be quasi-planar. The normal to the area may be the average normal of the area. The average normal may be:

number

number

[0051] In some embodiments, the predetermined threshold may be less than 10 degrees.

[0052] The present disclosure will be further described according to implementation embodiments, which will be described in detail with reference to the drawings, which are non-limiting implementation embodiments in which similar reference numerals indicate similar structures in at least two figures of the drawings. [Brief explanation of the drawings]

[0053] [Figure 1] 1A-1C are schematic diagrams illustrating application scenarios and structures of exemplary bone conduction speakers according to some embodiments of the present disclosure. [Figure 2] 1A-1C are schematic diagrams illustrating exemplary angular orientations according to some embodiments of the present disclosure. [Figure 3] 1 is a schematic diagram illustrating the structure of an exemplary bone conduction speaker that acts on human skin and bones according to some embodiments of the present disclosure. FIG. [Figure 4] 1A-1C are schematic diagrams illustrating relative angular displacement relationships of an exemplary bone conduction speaker according to some embodiments of the present disclosure. [Figure 5]FIG. 1 is a schematic diagram illustrating a frequency response curve of an exemplary bone conduction speaker according to some embodiments of the present disclosure. [Figure 6] 1A-1C are schematic diagrams illustrating the low frequency portion of the frequency response curve of an exemplary bone conduction speaker at different angles θ according to some embodiments of the present disclosure. [Figure 7] 1A-1C are schematic diagrams illustrating the high frequency portion of frequency response curves of exemplary bone conduction speakers with different panel and housing materials according to some embodiments of the present disclosure. [Figure 8] 1 is a schematic diagram showing an axial cross-sectional structure of an exemplary bone conduction speaker according to a first embodiment of the present disclosure. [Figure 9A] FIG. 10 is a schematic diagram showing an axial cross-sectional structure of an exemplary bone conduction speaker according to a second embodiment of the present disclosure. [Figure 9B] FIG. 10 is a schematic diagram showing an exploded structure of an exemplary bone conduction speaker according to a second embodiment of the present disclosure. [Figure 9C] FIG. 9C is a schematic diagram illustrating a longitudinal cross-sectional structure of the exemplary bone conduction speaker in FIG. 9B according to some embodiments of the present disclosure. [Figure 9D] 1A-1C are schematic diagrams illustrating the structure of a bracket in an exemplary bone conduction speaker according to some embodiments of the present disclosure. [Figure 9E] 1A-1C are schematic diagrams illustrating the structure of a bracket in an exemplary bone conduction speaker according to some embodiments of the present disclosure. [Figure 10] FIG. 10 is a schematic diagram showing an axial cross-sectional structure of an exemplary bone conduction speaker according to a third embodiment of the present disclosure. [Figure 11] FIG. 10 is a schematic diagram showing an axial cross-sectional structure of an exemplary bone conduction speaker according to a fourth embodiment of the present disclosure. [Figure 12] FIG. 10 is a schematic diagram showing the axial cross-sectional structure of an exemplary bone conduction speaker according to a fifth embodiment of the present disclosure. [Figure 13] FIG. 10 is a schematic diagram showing the axial cross-sectional structure of an exemplary bone conduction speaker according to a sixth embodiment of the present disclosure. [Figure 14] FIG. 10 is a schematic diagram showing the axial cross-sectional structure of an exemplary bone conduction speaker according to a seventh embodiment of the present disclosure. [Figure 15] FIG. 10 is a schematic diagram showing the axial cross-sectional structure of an exemplary bone conduction speaker according to an eighth embodiment of the present disclosure. [Figure 16] FIG. 10 is a schematic diagram showing the axial cross-sectional structure of an exemplary bone conduction speaker according to a ninth embodiment of the present disclosure. [Figure 17] 1 is a flowchart illustrating a method for installing a bone conduction speaker according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0054] In order to explain the technical solutions related to the embodiments of the present disclosure, a brief introduction to the drawings referred to in the description of the embodiments is provided below. Obviously, the drawings described below are only some examples or embodiments of the present disclosure. Those skilled in the art can apply the present disclosure to other similar scenarios according to these drawings without further creative efforts.

[0055] As used in this disclosure and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this disclosure, it is further understood that the terms "comprise," "include," "comprises," and / or "comprising" identify the presence of stated steps and elements, but do not preclude the presence or addition of one or more other steps and elements. The term "based on" means "based at least in part on." The term "in one embodiment" means "at least one embodiment." The term "another embodiment" means "at least one other embodiment." The term "A and / or B" means "at least one of A and B," or in other words, "A only, B only, or both A and B." Relevant definitions of other terms are provided in the description below.

[0056] Hereinafter, without loss of generality, when describing bone conduction-related technologies in this disclosure, the terms "bone conduction speaker" or "bone conduction earphone" will be used. This description is merely one form of bone conduction application. Those skilled in the art will recognize that "speaker" or "earphone" can be replaced with other similar terms, such as "player" or "hearing aid." In fact, various implementations of the present disclosure can easily be applied to other non-speaker-type hearing aids. For example, after understanding the basic principles of bone conduction speakers, those skilled in the art can make various modifications and changes to the form and details of specific methods and steps for implementing a bone conduction speaker without departing from these principles. In particular, ambient sound pickup and processing functions can be added to the bone conduction speaker to enable the speaker to function as a hearing aid. For example, a microphone may pick up ambient sounds around the user / wearer and transmit the processed sounds (or generated electrical signals) to the bone conduction speaker unit under a specific algorithm. That is, the bone conduction speaker may be modified to include a function for picking up ambient sounds and transmit the processed sounds to the user / wearer through the bone conduction speaker unit after specific signal processing, thereby realizing the function of a bone conduction hearing aid. By way of example only, the algorithms described herein may include noise cancellation, automatic gain control, acoustic feedback suppression, wide dynamic range compression, active environmental awareness, active noise reduction, directional processing, anti-tinnitus processing, multi-channel wide dynamic range compression, active feedback suppression, volume control, etc., or any combination thereof.

[0057] Bone conduction speakers transmit sound through bones to the auditory system, allowing people to hear. Generally, bone conduction speakers generate and transmit sound through the following steps: In step 1, the bone conduction speaker may acquire or generate a signal containing sound information, such as a current signal and / or a voltage signal containing acoustic information. In step 2, a driver of the bone conduction speaker, also called a transmission device, may generate vibrations based on the signal. In step 3, the transmission component may transmit the vibrations to a panel or housing of the speaker.

[0058] In step 1, the bone conduction speaker may acquire or generate a signal containing sound information according to different methods. Sound information may refer to a video or audio file with a specific data format, or to data or files that can be converted into sound in a specific manner. The signal containing sound information may be acquired from a storage unit within the bone conduction speaker itself, or from an information generation, storage, or transmission system other than the bone conduction speaker. The sound signal discussed here is not limited to an electrical signal but may include other forms, such as optical, magnetic, or mechanical signals, that contain sound information that can be processed to generate vibrations. The sound signal is not limited to a single signal source but may be acquired from multiple signal sources. Each of the multiple signal sources may be related or unrelated to each other. The transmission or generation of the sound signal may be wired or wireless, and may be real-time or delayed. For example, the bone conduction speaker may receive an electrical signal containing sound information via a wired or wireless connection, or may generate a sound signal by directly acquiring data from a storage medium. In some embodiments, a component with a sound collection function may be added to the bone conduction hearing aid to receive and process ambient sound signals to achieve noise reduction. Wired connections may include, but are not limited to, metal cables, optical cables, and hybrid metal-optical cables. Hybrid metal-optical cables may include coaxial cables, communication cables, flexible cables, spiral cables, non-metallic sheathed cables, metallic sheathed cables, multi-core cables, twisted pair cables, ribbon cables, shielded cables, telecommunication cables, paired cables, twin-core parallel wiring, or twisted pair cables.

[0059] The above embodiments are for convenience of explanation only. The wired connection medium may also be of other types, such as other electrical or optical signal transmission carriers. The wireless connection may include, but is not limited to, radio communication, free-space optical communication, voice communication, or electromagnetic induction. The wireless communication may include, but is not limited to, IEEE 302.11 series standards, IEEE 302.15 series standards (e.g., Bluetooth technology, ZigBee technology, etc.), first-generation mobile communication technologies, second-generation mobile communication technologies (e.g., FDMA, TDMA, SDMA, CDMA, SSMA), general packet radio service technologies, third-generation mobile communication technologies (e.g., CDMA2000, WCDMA, TD-SCDMA, WiMAX), fourth-generation mobile communication technologies (e.g., TD-LTE, FDD-LTE), satellite communication (e.g., GPS technology), near-field communication (NFC), or other technologies operating in the ISM band (e.g., 2.4 GHz). Free-space optical communication may include, but is not limited to, visible light, infrared signals, etc. Audio communication may include, but is not limited to, sound waves, ultrasonic signals, etc. Electromagnetic induction may include, but is not limited to, short-range wireless communication technology. The above embodiments are for convenience of explanation only. The wireless connection medium may also be of other types, such as Z-wave technology, other charged civilian radio frequency bands, or military radio frequency bands. For example, as some exemplary scenarios of technology, a bone conduction speaker may receive a signal containing sound information from another device via Bluetooth technology or directly receive data from the bone conduction speaker's storage unit to generate a sound signal.

[0060] Here, the term storage device / storage unit refers to a storage device on a storage system, including direct-attached storage, network-attached storage, storage area network, etc. The storage device may include, but is not limited to, general-purpose storage devices such as solid-state storage devices (e.g., solid-state disks, hybrid hard disks, etc.), mechanical hard disks, USB flash memory, memory sticks, memory cards (e.g., CF, SD, etc.), other drives (e.g., CD, DVD, HD DVD, Blu-ray®, etc.), random access memory (RAM), read-only memory (ROM), etc. The RAM may include, but is not limited to, counter discharge tubes, selectrons, delay line memories, Williams tubes, dynamic random access memory (DRAM), static random access memory (SRAM), thyristor random access memory (T-RAM), zero capacitor random access memory (Z-RAM), etc. ROM may include, but is not limited to, bubble memory, twister memory, film memory, plated wire memory, magnetic core memory, drum memory, CD-ROM, hard disk, tape, nonvolatile random access memory (NVRAM), phase change memory, magnetoresistive random access memory, ferroelectric random access memory, nonvolatile SRAM, flash memory, electrically erasable programmable read-only memory, erasable programmable read-only memory, programmable read-only memory, mask ROM, floating gate random access memory, nano random access memory, racetrack memory, resistive memory, programmable metallization unit, etc. The above storage devices / storage units are a list of some examples. The storage devices / storage units may use storage devices that are not limited to these.

[0061] FIG. 1 is a schematic diagram illustrating an application scenario and structure of an exemplary bone conduction speaker according to some embodiments of the present disclosure. As shown in FIG. 1, the bone conduction speaker may include a driver 101, a transmission component 102, a panel 103, a housing 104, etc. The driver 101 may transmit a vibration signal to the panel 103 and / or the housing 104 via the transmission component 102, thereby transmitting sound to the human body by bringing the panel 103 or the housing 104 into contact with human skin. In some embodiments, the bone 103 and / or the housing 104 of the bone conduction speaker may transmit sound to the human body by contacting the human skin at the tragus. In some embodiments, the panel 103 and / or the housing 104 may also contact the human skin behind the pinna.

[0062] Bone conduction speakers may generate sound by converting signals containing sound information into vibrations. The generation of vibrations may involve energy conversion. Bone conduction speakers may convert signals into mechanical vibrations using a specific driver. The conversion process may involve the coexistence and conversion of several different types of energy. For example, an electrical signal may be directly converted into mechanical vibrations via a converter to generate sound. As another example, an optical signal may contain sound information, and the driver may implement a process to convert the optical signal into a vibration signal, or first convert the optical signal into an electrical signal and then convert the electrical signal into a vibration signal. Other types of energy that can coexist and be converted during the operation of the driver may include thermal energy, magnetic field energy, etc. Energy conversion methods of the driver may include, but are not limited to, moving coil, electrostatic, piezoelectric, moving iron, pneumatic, electromagnetic, etc. The frequency response range and sound quality of a bone conduction speaker may be affected by different conversion methods and the performance of various physical components within the driver. For example, in a dynamic coil transducer, a wound cylindrical coil may be mechanically connected to a vibration transmission sheet, and a signal current in a magnetic field may drive the coil to drive the vibration transmission sheet and generate sound. Furthermore, the material stretching and contraction of the vibration transmission sheet, the deformation of the folds, the size, shape, and fixing method of the folds, and the magnetic density of the permanent magnets can all significantly affect the final sound quality of the bone conduction speaker. As another example, the vibration transmission sheet may have a mirror symmetric structure, a centrosymmetric structure, or an asymmetric structure. By providing a discontinuous porous structure on the vibration transmission sheet, the vibration transmission sheet may be able to displace more, thereby increasing the sensitivity of the bone conduction speaker and improving vibration and sound output. As another example, the vibration transmission sheet may have a torus structure, with multiple struts arranged within a torus radiating toward the center.

[0063] Obviously, after understanding the basic principles of the conversion method and specific devices that can affect the sound quality of a bone conduction speaker, those skilled in the art can make appropriate selections, combinations, modifications, or changes to the above-mentioned influencing factors to achieve ideal sound quality without deviating from these principles. For example, using a high-density permanent magnet and a more ideal vibration plate material or design can achieve better sound quality. The term "sound quality" as used herein may be understood to reflect the quality of sound and refers to the fidelity of audio after processing, transmission, or other processes. Sound quality is primarily described by three components: loudness, tone, and timbre. Loudness refers to the subjective perception of sound intensity by the human ear and may be proportional to the logarithm of the sound intensity. The greater the logarithm of the sound intensity, the louder the sound. Loudness may also be related to the frequency and waveform of a sound. Tone, also known as pitch, refers to the subjective perception of the frequency of sound wave vibrations by the human ear. Tone may be primarily determined by the fundamental frequency of a sound. The higher the fundamental frequency, the higher the tone. Tone may also be related to the intensity of a sound. Timbre refers to the subjective perception of the characteristics of a sound by the human ear. Timbre may be primarily determined by the spectral structure of a sound and may also be related to factors such as the loudness, duration, buildup process, or decay process of a sound. The spectral structure of a sound may be described by the fundamental frequency, the count of harmonic frequencies, the distribution of harmonic frequencies, magnitude, and phase relationship. Different spectral structures may have different timbres. Two sounds may have the same fundamental frequency and loudness, but if the harmonic structures of the two sounds are different, they may also have different timbres.

[0064] 1, according to the bone conduction speaker illustrated by some embodiments of the present disclosure, the driving force generated by the driving device may be located on a straight line B (i.e., the vibration direction of the driving force). The straight line B and a normal line A of the panel 103 may form an angle θ. That is, the line B is not parallel to the line A.

[0065] The panel may have an area that contacts or is adjacent to a user's body, such as human skin. It should be understood that if the panel is covered with another material (e.g., a soft material such as silicone) to increase the user's wearing comfort, the panel and the user's body may be adjacent to each other instead of being in direct contact. In some embodiments, when the bone conduction speaker is worn on the user's body, all areas of the panel may contact or be adjacent to the user's body. In some embodiments, when the bone conduction speaker is worn on the user's body, only a portion of the panel may contact or be adjacent to the user's body. In some embodiments, the area of ​​the panel used to contact or be adjacent to the user's body may occupy 50% or more of the panel area, and more preferably, 60% or more of the panel area. In general, the area of ​​the panel that contacts or is adjacent to the user's body may be flat or curved.

[0066] In some embodiments, if the area of ​​the panel that contacts or is adjacent to the user's body is flat, the normal may meet the general definition of a normal. In some embodiments, if the area of ​​the panel that contacts or is adjacent to the user's body is curved, the normal may be the average normal of that area.

[0067] The average normal may be defined as:

number

[0068] Additionally, a curved surface may be a quasi-plane that is close to a plane, i.e., a plane where the angle between the normal of any point within at least 50% of the plane and the average normal is less than a predetermined threshold. In some embodiments, the threshold may be less than 10°. In some embodiments, the threshold may even be less than 5°.

[0069] In some embodiments, a line B on which the driving force is located and a normal A' of the area on the panel 103 that is in contact with or adjacent to the user's body may have an angle θ. The value of the angle θ may range from 0° to 180°, and may even be within the range of 0° to 180°, but may not be equal to 90°. In some embodiments, if the line B has a positive direction pointing out of the bone conduction speaker, and the normal A of the panel 103 (or the normal A' of the area on the panel 103 that is in contact with or adjacent to the user's body) also has a positive direction pointing out of the bone conduction speaker, the angle θ between the line A or A' and the line B in their positive directions may be an acute angle, i.e., 0°<θ<90°.

[0070] FIG. 2 is a schematic diagram illustrating exemplary angular directions according to some embodiments of the present disclosure. As shown in FIG. 2, in some embodiments, the driving force generated by the driving device may have components in the first and / or third quadrants of an x-o-y plane coordinate system. The x-o-y plane coordinate system is a reference coordinate system. The origin o may be located at the contact surface between the human body and the panel and / or housing after the bone conduction speaker is worn on the human body. The x-axis may be parallel to the human's coronal axis, and the y-axis may be parallel to the human's sagittal axis. The positive direction of the x-axis may point toward the outside of the human body, and the positive direction of the y-axis may point toward the front of the human body. Quadrants should be understood as four regions divided by the horizontal axis (i.e., the x-axis) and the vertical axis (i.e., the y-axis) in a planar rectangular coordinate system. Each region can be referred to as a quadrant. Each quadrant may be centered at the origin, with the x-axis and y-axis as dividing lines. The upper right region (the region bounded by the positive semi-axis of the x-axis and the positive semi-axis of the y-axis) can be referred to as the first quadrant. The upper left region (the region bounded by the negative semi-axis of the x-axis and the positive semi-axis of the y-axis) can be referred to as the second quadrant. The lower left region (the region bounded by the negative semi-axis of the x-axis and the negative semi-axis of the y-axis) can be referred to as the third quadrant. The lower right region (the region bounded by the positive semi-axis of the x-axis and the negative semi-axis of the y-axis) can be referred to as the fourth quadrant. Points on the coordinate axes do not belong to any quadrant. It should be understood that the driving forces described herein may be directly located in the first and / or third quadrants of the xoy-plane coordinate system. The driving forces may also be directed in other directions, and the projections or components in the first and / or third quadrants of the xoy-plane coordinate system may or may not be zero, and the projections or components in the z-axis direction may or may not be zero. The z-axis may be perpendicular to the xoy plane and may pass through the origin o. In some embodiments, the minimum angle θ between the line along which the driving force lies and the normal to the area on the panel that contacts or is adjacent to the user's body may be any acute angle.For example, the angle θ may be in a preferred range of 5° to 80°, a more preferred range of 15° to 70°, a more preferred range of 25° to 60°, a more preferred range of 25° to 50°, a more preferred range of 28° to 50°, a more preferred range of 30° to 39°, a more preferred range of 31° to 38°, a more preferred range of 32° to 37°, a more preferred range of 33° to 36°, a more preferred range of 33° to 35.8°, or a more preferred range of 33.5° to 35°. Specifically, the angle θ may be 26°, 27°, 28°, 29°, 30°, 31°, 32°, 33°, 34°, 34.2°, 35°, 35.8°, 36°, 37°, or 38°, etc. The error may be controlled to within 0.2 degrees. It should be noted that the description of the direction of the driving force should not be understood as a limitation of the driving force in this disclosure. In some other embodiments, the driving force may also have components in the second and fourth quadrants of the x-o-y plane coordinate system, may be located on the y-axis, etc.

[0071] FIG. 3 is a schematic diagram illustrating the structure of an exemplary bone conduction speaker that interacts with human skin and bones according to some embodiments of the present disclosure. The bone conduction speaker may receive, pick up, or generate a signal containing sound information and convert the sound information into sonic vibrations via a driver. The vibrations may be transmitted to the human skin 320 through a transmission component in contact with a panel or housing, and the vibrations may be further transmitted to the human skeleton 310 so that the user can hear the sound. Without loss of generality, the subject of the auditory system and sensory organs may be a human or an animal with an auditory system. Note that the following description of the use of a bone conduction speaker in humans does not limit the use scenario of the bone conduction speaker. Similar descriptions may also be applied to other animals.

[0072] As shown in FIG. 3, the bone conduction speaker may include a driver (also referred to as a transducer in other embodiments), a transmission component 303, a panel 301, and a housing 302.

[0073] The vibrations of the panel 301 may be transmitted through tissue and bone to the auditory nerve so that a person can hear the sound. The panel 301 may contact the human skin directly or through a vibration-transmitting layer made of a specific material. The area where the panel 301 contacts the human body may be near the tragus, mastoid process, behind the ear, or other locations.

[0074] The physical properties of the panel, such as mass, size, shape, stiffness, and vibration damping, can all affect the vibration efficiency of the panel. Those skilled in the art may select a panel made of an appropriate material according to actual needs, or may use different molds to inject the panel into different shapes. For example, the shape of the panel may be rectangular, circular, or elliptical. As another example, the shape of the panel may be a shape obtained by cutting the edge of a rectangle, circle, or ellipse (such as, but not limited to, symmetrically cutting a circle to obtain a shape resembling an ellipse or oval). More preferably, the panel may be hollow. By way of example only, the area size of the panel may be set as needed. In some embodiments, the area size of the panel is 20 mm or less. 2 ~1000mm 2 Specifically, the side length of the panel may be in the range of 5 mm to 40 mm, or 18 mm to 25 mm, or 11 to 18 mm. For example, the panel may be rectangular with a length of 22 mm and a width of 14 mm. As another example, the panel may be oval with a major axis of 25 mm and a minor axis of 15 mm.

[0075] Panel materials referred to herein may include, but are not limited to, steel, alloys, plastics, and monolithic or composite materials. Steels may include, but are not limited to, stainless steel, carbon steel, etc. Alloys may include, but are not limited to, aluminum alloys, chromium-molybdenum steel, rhenium alloys, magnesium alloys, titanium alloys, magnesium-lithium alloys, nickel alloys, etc. Plastics may include, but are not limited to, acrylonitrile butadiene styrene (ABS), polystyrene (PS), high impact polystyrene (HIPS), polypropylene (PP), polyethylene terephthalate (PET), polyester (PES), polycarbonate (PC), polyamide (PA), polyvinyl chloride (PVC), polyethylene, blown nylon, etc. Monolithic or composite materials may include, but are not limited to, glass fiber, carbon fiber, boron fiber, graphite fiber, graphene fiber, silicon carbide fiber, aramid fiber, or other reinforcing materials. The single or composite materials may also include composites of other organic and / or inorganic materials such as glass fiber reinforced unsaturated polyester, various types of glass steel with an epoxy or phenolic resin matrix, etc.

[0076] In some other embodiments, the exterior of the bone conduction speaker panel may be wrapped with a vibration transmission layer that contacts the skin. The vibration system consisting of the panel and the vibration transmission layer may transmit the generated sound vibrations to human tissue. The vibration transmission layer may include multiple layers. The vibration transmission layer may be formed of one or more materials, and the materials of different vibration transmission layers may be the same or different. Multiple vibration transmission layers may be overlapped vertically on the panel, horizontally on the panel, or at an angle to the panel. The angles between each layer and the panel may be the same or different, or any combination thereof. The vibration transmission layer may be made of a material with specific absorption, flexibility, and chemical properties, such as plastic (including, but not limited to, high-molecular-weight polyethylene, blown nylon, engineering plastics, etc.), rubber, or other single or composite materials that can achieve the same performance.

[0077] In some embodiments, when the bone conduction speaker is worn on a user's body, the entire area of ​​the panel may contact or be adjacent to the user's body. In some embodiments, when the bone conduction speaker is worn on a user's body, only a portion of the panel may contact or be adjacent to the user's body. In some embodiments, the area of ​​the panel used to contact or be adjacent to the user's body may occupy 50% or more of the panel area, and more preferably 60% or more of the panel area. Generally, a user's skin is relatively flat. Placing the panel on a flat or quasi-flat surface without significant variation in the area that contacts the skin increases the area of ​​the panel that contacts the skin, resulting in a higher volume. For example, the panel may have a composite structure with a flat center and arc-chamfered edges. Therefore, the panel may have a curved surface to ensure complete contact with human skin and compatibility with different people.

[0078] In some embodiments, the panel 301 may cooperate with the housing 302 to form a sealed or semi-sealed cavity (e.g., a hole in the panel or housing) for accommodating a driving device. Specifically, the panel 301 and the housing 302 may be integrally formed, i.e., the panel and the housing may be constructed of the same material, with no structural boundary between the two. The panel 301 may also be mechanically connected to the housing 302 by snapping, riveting, hot melting, or welding. In some other embodiments, the panel 301 and the housing 302 may be mechanically connected via a connecting medium. The connecting medium may include an adhesive such as polyurethane, polystyrene, polyacrylate, ethylene-vinyl acetate copolymer, shellac, or butyl rubber. The connecting medium may also include connecting components with specific structures, such as a vibration transmission sheet or a connecting rod. The rigidity of the housing, the rigidity of the panel, and the rigidity of the connection between the housing and the panel can all affect the frequency response of the speaker. In some embodiments, both the housing and the panel may be formed of a material with higher rigidity, while the rigidity of the connecting medium between the housing and the panel is relatively low. When the driver vibrates, the panel and housing may vibrate asynchronously. In some other embodiments, both the housing and the panel may be formed of a material with higher stiffness, and the stiffness of the connecting medium between the housing and the panel may also be increased, resulting in a higher overall stiffness of the vibration system, and the resonant portion may contain more high-frequency components. In some embodiments, the stiffness of the panel and the housing may be increased by adjusting the stiffness of the panel and the housing, and the peaks and valleys in the high-frequency region may be adjusted to a higher frequency band region. A more detailed description of the relationship between component stiffness and sound quality may be found elsewhere in this disclosure (see, for example, FIG. 7 and its discussion).

[0079] In some embodiments, the housing may have greater rigidity and lighter weight and may mechanically vibrate as a whole. The housing may ensure vibration consistency and create mutually offset sound leakage, ensuring good sound quality and high volume. In some embodiments, the housing may or may not have holes. For example, holes in the housing may adjust sound leakage from a bone conduction speaker.

[0080] Stiffness may be understood as the ability of a material or structure to resist elastic deformation when subjected to a force, and may be related to the elastic modulus of the material, shape, structure, or installation method of the part. For example, the stiffness of a part is positively related to the elastic modulus and thickness of the part, and negatively related to the surface area of ​​the part. In some embodiments, the part may be a panel, a housing, a transmission part, etc. Specifically, the stiffness of a sheet-like part such as a panel may be expressed by the following formula:

number

number

[0081] In some embodiments, the driver may be located in an enclosed or semi-enclosed space formed by the panel and the housing (e.g., with a hole in the panel or housing). In some other embodiments, the driver may be located in an enclosed or semi-enclosed space formed by the housing, and the panel is provided independently of the housing. More description of separately providing the panel and the housing may be found elsewhere in this disclosure (e.g., see FIG. 15 and its description). The driver may convert electrical signals into vibrations of different frequencies and amplitudes. The driver's operating modes may include, but are not limited to, moving coil, moving iron, piezoelectric ceramic, or other operating methods.

[0082] For the sake of example only, the following description may take the moving coil method as an example. In FIG. 3, the driving device may use the moving coil driving method and may include a coil 304 and a magnetic system 307.

[0083] The magnetic system 307 may include a first magnetic component 3071, a first magnetic conductive component 3072, and a second magnetic conductive component 3073. A magnetic component, as described in this disclosure, refers to a component that may generate a magnetic field, such as a magnet. A magnetic component may have a magnetization direction, which refers to the direction of the magnetic field within the magnetic component. The first magnetic component 3071 may include one or more magnets. In some embodiments, the magnets may include metal alloy magnets, ferrites, etc. The metal alloy magnets may include neodymium magnets, samarium-cobalt, aluminum-nickel-cobalt, iron-chromium-cobalt, aluminum-iron-boron, iron-carbon-aluminum, etc., or any combination thereof. The ferrites may include barium ferrite, steel ferrite, manganese ferrite, lithium-manganese ferrite, etc., or any combination thereof.

[0084] The magnetic conductive part may also be referred to as a magnetic field concentrator or iron core, which may adjust the distribution of a magnetic field (e.g., the magnetic field generated by the first magnetic part 3071). In some embodiments, the bottom surface of the first magnetic conductive part 3072 may be mechanically connected to the top surface of the first magnetic part 3071. The second magnetic conductive part 3073 may have a concave structure that may include a bottom wall and a side wall. The inside of the bottom wall of the second magnetic conductive part 3073 may be mechanically connected to the first magnetic part 3071, and the side wall may surround the first magnetic part 3071 and form a magnetic gap with the first magnetic part 3071. The mechanical connection between the first magnetic conductive part 3072, the second magnetic conductive part 3073, and the first magnetic part 3071 may include a bonded connection, a locking connection, a welded connection, a riveted connection, a bolted connection, etc., or any combination thereof.

[0085] The magnetic conductive component may include an element made of a soft magnetic material. In some embodiments, exemplary soft magnetic materials may include metal materials, metal alloy materials, metal oxide materials, amorphous metal materials, etc. For example, soft magnetic materials may include iron, iron-silicon-based alloys, iron-aluminum-based alloys, nickel-iron-based alloys, iron-cobalt-based alloys, low-carbon steel, silicon steel sheets, silicon steel sheets, ferrites, etc. In some embodiments, the magnet may be manufactured by, for example, casting, plastic processing, cutting, powder metallurgy, etc., or any combination thereof. Casting may include sand casting, investment casting, pressure casting, centrifugal casting, etc. Plastic processing may include rolling, casting, forging, stamping, extrusion, drawing, etc., or any combination thereof. Cutting may include turning, milling, planning, grinding, etc. In some embodiments, the magnetic conductive component may be manufactured by 3D printing techniques, computer numerically controlled machine tools, etc.

[0086] It should be understood that the description of the structure of the driver should not be construed as a limitation of the present disclosure. In some embodiments, the magnetic system may include multiple magnetic components that may be stacked together from top to bottom. Additional magnetic conductive components may be installed between adjacent magnetic components, and other magnetic conductive components may be installed on top of the upper magnetic component. The magnetic components may be components that generate a magnetic field. The magnetic conductive components may adjust the distribution of the magnetic field. The structure of the magnetic system installed according to specific magnetic field distribution requirements may be used in a bone conduction speaker and is not limited to the present disclosure.

[0087] The coil 304 may be disposed within the magnetic gap between the first magnetic component 3071 and the second magnetic conductive component 3073. After energization, the coil 304 located within the magnetic gap may be driven to oscillate by an Ampere force (e.g., a driving force). The magnetic system 307 may generate vibrations through the action of a repulsive force. The driving device may further include a transmission component 303 that transmits the vibrations of the coil 304 and / or the magnetic system 307 to the panel and / or housing. The Ampere force may be a force that a conductor experiences within a magnetic field. The direction of the Ampere force may be perpendicular to a plane determined by the direction of the conductor and the magnetic field, and may be determined by the left-hand rule. When the current direction and the magnetic field direction change, the direction of the Ampere force may also change. In some embodiments, the magnetic field generated by the magnetic system is static. When the current direction changes, the direction of the driving force may switch along a straight line. The straight line may be considered as the line along which the driving force is located. The coil may generate vibrations due to a driving force, and the magnetic system may generate vibrations due to a reciprocating force. Both vibrations are generally along the same line, but in opposite directions. The line can be considered as the line along which the vibrations are located, and may be the same as (i.e., parallel to) or the same as the line along which the driving force is located.

[0088] In some embodiments, the vibrations of the coil may be transmitted to the panel and / or housing through a first transmission part, and the vibrations of the magnetic system may be transmitted to the panel and / or housing through a second transmission part.

[0089] In some embodiments, after energization, the coil may generate vibrations under the influence of Ampere's force. The vibrations of the coil may be transmitted to the panel and / or housing through a first transmission component, and the coil may interact with the magnetic system via a magnetic field. The reaction force received by the magnetic system may also generate vibrations, and the vibrations of the magnetic system may be transmitted to the panel and / or housing through a second transmission component. In some embodiments, the transmission component may include a connecting rod, a connecting post, and / or a vibration transmission sheet. In some embodiments, the transmission component has a moderate elastic force that creates a damping effect during the vibration transmission process, which may reduce the vibration energy transmitted to the housing. This effectively suppresses sound leakage from the bone conduction speaker due to housing vibration, avoids the generation of abnormal noise due to abnormal resonance, and improves sound quality. In addition, the position of the transmission component within / on the housing may have different degrees of impact on the vibration transmission efficiency. In some embodiments, the transmission component may be in a different state, such as suspended or supported, for the driver. In addition, the vibration transmission sheet may be a thin plate. The main body of a specific vibration transmission sheet may be a ring structure, and multiple branches or multiple connecting pieces arranged radially toward the center may be provided on the ring main body structure. The number of branches or connecting pieces may be two or more. A more detailed description of the transmission components may be found elsewhere in this disclosure (see, for example, the specific embodiments section).

[0090] In some embodiments, the line on which the driving force is located may be collinear or parallel to the line on which the driver vibrates. For example, in a driver based on the principle of a moving coil, the direction of the driving force may be the same as or opposite to the vibration direction of the coil and / or magnetic system. The panel may be flat or curved, or may have some protrusions or grooves. In some embodiments, when the bone conduction speaker is worn on a user's body, the normal of the area on the panel that contacts or is adjacent to the user's body is not parallel to the line on which the driving force is located. Generally, the area on the panel that contacts or is adjacent to the user's body may be relatively flat, more specifically, a plane or quasi-plane with little change in curvature. If the area on the panel that contacts or is adjacent to the user's body is flat, the normal at any point on the panel may be the normal to the area. If the area on the panel that contacts or is adjacent to the user's body is not flat, the normal to the area may be an average normal. More explanation of the average normal may be found elsewhere in this disclosure (see, for example, FIG. 1 and its description). In some embodiments, if the area on the panel that contacts or is adjacent to the user's body is not flat, the normal to the area may be determined as follows: A point within the area where the panel is in contact with human skin may be selected, the tangent plane of the panel at the point may be determined, and then a line that passes through the point and is perpendicular to the tangent plane may be determined. The straight line may be the normal to the panel. According to certain embodiments of the present disclosure, the line on which the driving force is located (or the line on which the driver vibrates) may have an angle θ (0°<θ<180°) with the normal to the area. In some embodiments, the line on which the driving force is located may have a positive direction pointing out of the bone conduction speaker through the panel (or the surface of the panel and / or housing that is in contact with human skin), and the normal to the particular panel (or the surface of the panel and / or housing that is in contact with human skin) may have a positive direction pointing out of the bone conduction speaker, and the angle in the positive direction between the two lines may be an acute angle.

[0091] In some embodiments, the bone conduction speaker 300 may include a panel 301, a housing 302, a first transmission part 303, a coil 304, a vibration transmission sheet 305, a second transmission part 306, and a magnetic system 307. Vibrations of the coil 304 and the magnetic system 307 may be transmitted to the panel 301 and / or the housing 302 via different paths. For example, vibrations of the coil 304 may be transmitted to the panel 301 and / or the housing 302 via a first transmission path, and vibrations of the magnetic system 307 may be transmitted to the panel 301 and / or the housing 302 via a second transmission path. The first transmission path may include the first transmission part 303, and the second transmission path may include the second transmission part 306, the vibration transmission sheet 305, and the first transmission part 303. Specifically, a portion of the first transmission part 303 may have a flanged structure. The flange may be ring-shaped to fit the structure of the coil 304 and may be mechanically connected to one end surface of the coil 304. Another part of the first transmission part 303 may be a connecting rod that may be mechanically connected to the panel and / or housing. The coil 304 may be fully or partially sleeved in the magnetic gap of the magnetic system 307. In the second transmission path, the second transmission part 306 may be mechanically connected to the magnetic system 307 and the vibration transmission sheet 305. An edge of the vibration transmission sheet 305 may be fixed to the flange of the first transmission part 303. The center of the vibration transmission sheet 305 may be mechanically connected to one end of the second transmission part 306. The edge of the vibration transmission sheet 305 may be mechanically connected to the inside of the flange of the first transmission part 303, and the connection may include a snap-fit ​​connection, a hot-press connection, a rivet connection, a bonded connection, an injection-molded connection, etc. It should be noted that the first and second transmission paths may also have other structures, and this embodiment should not be construed as a limitation on the transmission components, a more detailed description of which may be found elsewhere in this disclosure.

[0092] In some embodiments, both the coil 304 and the magnetic system 307 may have ring structures. In some embodiments, the coil 304 and the magnetic system 307 may have axes parallel to each other, and the axes of the coil 304 and the magnetic system 307 may be perpendicular to the radial plane of the coil 304 and / or the radial plane of the magnetic system 307. In some embodiments, the coil 304 and the magnetic system 307 may have the same central axis. The central axis of the coil 304 may be perpendicular to the radial plane of the coil 304 and pass through the geometric center of the coil 304. The central axis of the magnetic system 307 may be perpendicular to the radial plane of the magnetic system 307 and pass through the geometric center of the magnetic system 307. The axis of the coil 304 or the magnetic system 307 and the normal to the panel 301 may have the angle θ described above.

[0093] In this embodiment, after being energized, the coil 304 generates an ampere of force and vibration within the magnetic field generated by the magnetic system 307, and the vibration of the coil 304 may be transmitted to the panel 301 through the first transmission part 303. The vibration generated by the reaction force received by the magnetic system 307 may be transmitted to the panel 301 through the second transmission part 306, the vibration transmission sheet 305, and the first transmission part 303. The vibration of the coil 304 and the vibration of the magnetic system 307 may be transmitted to the skin and bones of the human body through the panel 301, thereby allowing people to hear the sound. In short, the vibration generated by the coil 304 and the vibration generated by the magnetic system 307 may form a composite vibration that may be transmitted to the panel 301. The composite vibration may be transmitted to the skin and bones of the human body through the panel 301, thereby allowing people to hear the bone-conducted sound.

[0094] By way of example only, the relationship between the driving force F and the skin deformation S will be described with reference to Figure 3. When the driving force generated by the driver is parallel to the normal to the panel 302 (i.e., when the angle θ is zero), the relationship between the driving force and the overall skin deformation may be expressed as:

number

[0095] When the driving force of the driving device is perpendicular to the normal of the area on the panel contacting or adjacent to the user's body (i.e., the angle θ is 90 degrees), the relationship between the normal driving force and the overall skin deformation may be expressed as:

number

number

[0096] When the driving force of the driving device is not parallel to the normal of the area on the panel that is in contact with or adjacent to the user's body, the horizontal and vertical driving forces may be expressed as equations (7) and (8) below.

number

number

number

[0097] For a detailed description of the relationship between the angle θ and the overall deformation of the skin when the Poisson's ratio of the skin is 0.4, see FIG.

[0098] 4 is a schematic diagram illustrating the angular relative displacement relationship of an exemplary bone conduction speaker according to some embodiments of the present disclosure. As shown in FIG. 4, the relationship between the angle θ and the overall skin deformation may be such that the larger the angle θ, the larger the relative displacement and the larger the overall skin deformation S. The larger the angle θ, the smaller the relative displacement and the larger the vertical skin deformation S.

number

number

[0099] The volume of bone conduction earphones in the low frequency part may be positively related to the overall skin deformation S. The larger S, the higher the volume of the low frequency part of bone conduction. The volume of bone conduction earphones in the high frequency part is related to the vertical skin deformation.

number

number

[0100] When the Poisson's ratio of the skin is 0.4, the skin deformation perpendicular to the angle θ between the angle θ and the total skin deformation S is

number

number

[0101] From equation (8) and the curve in Figure 4, as the angle θ increases, the rate at which the deformation S of the entire skin increases is

number

number

[0102] FIG. 5 is a schematic diagram illustrating a frequency response curve of an exemplary bone conduction speaker according to some embodiments of the present disclosure. As shown in FIG. 5, the horizontal axis represents vibration frequency, and the vertical axis represents vibration intensity of the bone conduction earphone. In some embodiments, the flatter the frequency response curve is in the frequency range of 500-6000 Hz, the better the sound quality of the bone conduction earphone is considered to be. The structure, component design, and material properties of the bone conduction earphone may affect the frequency response curve. Generally, low frequencies refer to sounds higher than 500 Hz, mid-frequency frequencies refer to sounds in the range of 500-4000 Hz, and high frequencies refer to sounds above 4000 Hz. As shown in FIG. 5, the frequency response curve of the bone conduction earphone may have two resonance peaks (510 and 520) in the low frequency range, a first high-frequency valley 530 in the high frequency range, a first high-frequency peak 540, and a second high-frequency peak 550. Two resonance peaks (510, 520) in the low frequency range may be generated by the combined action of the vibration transmission sheet and the earphone fixation component. A first high frequency valley 530 and a first high frequency peak 540 may be generated by deformation of the housing side at high frequencies, and a second high frequency peak 550 may be generated by deformation of the shell panel at high frequencies.

[0103] The locations of different resonant peaks and high-frequency peaks / valleys may be related to the stiffness of the corresponding components. This stiffness, commonly referred to as flexibility and stiffness, is the ability of a material or structure to resist elastic deformation when subjected to force. Stiffness is related to the Young's modulus of the material itself and the dimensions of the structure. The greater the stiffness, the less the structure will deform when subjected to force. As noted above, the frequency response between 500 and 6000 Hz is particularly important for bone conduction earphones. In this frequency range, sharp peaks and valleys are not expected. The flatter the frequency response curve, the better the sound quality of the earphones. In some embodiments, the high-frequency peaks and valleys may be adjusted to higher frequencies by adjusting the stiffness of the shell panel and shell back panel.

[0104] FIG. 6 is a schematic diagram illustrating the low-frequency portion of the frequency response curve of an exemplary bone conduction speaker at different angles θ according to some embodiments of the present disclosure. As shown in FIG. 6, the panel may contact the skin and transmit vibrations to the skin. In this process, the skin may also affect the vibration of the bone conduction speaker, thereby affecting the frequency response curve of the bone conduction speaker. From the above analysis, it can be seen that the larger the angle, the greater the overall deformation of the skin under the same driving force, which corresponds to a decrease in the elasticity of the skin relative to the panel when used with a bone conduction speaker. Furthermore, it can be seen that the line on which the driving force of the driver is located and the normal to the area on the panel that is in contact with or adjacent to the user's body may form a certain angle θ. In particular, as the angle θ increases, the resonance peak in the low-frequency range of the frequency response curve may be adjusted to the lower frequency range, resulting in a deeper low-frequency band and a larger low-frequency portion. Compared to other technical means for improving the low-frequency portion of sound, such as adding a vibration-transmitting sheet to a bone conduction speaker, setting the angle effectively suppresses the increase in vibration while increasing low-frequency energy, thereby relatively reducing vibration sensation, thereby significantly improving the low-frequency sensitivity of the bone conduction speaker and improving sound quality and the human experience. Note that in some embodiments, the increase in the low-frequency range and low vibration may be expressed as the angle θ increases in the range of 0° to 90°, and the energy in the low-frequency range of the vibration or sound signal increases, and vibration sensation increases. However, because the increase in energy in the low-frequency range may be greater than the increase in vibration, the relative effect is relatively reduced.

[0105] From Figure 6, we can see that when the angle is relatively large, the low-frequency resonance peak appears in a lower frequency range, and the flat part of the frequency curvature becomes longer, thereby improving the sound quality of the earphone.

[0106] FIG. 7 is a schematic diagram illustrating the high-frequency portion of the frequency response curve of an exemplary bone conduction speaker with different panel and housing materials according to some embodiments of the present disclosure. As shown in FIG. 7, when the panel and housing materials are stiff, the frequencies corresponding to the first and second high-frequency peaks are higher. When the panel and housing materials are soft, the frequencies corresponding to the first and second high-frequency peaks are lower. When the panel and housing materials are stiff, the frequency corresponding to the first high-frequency valley is higher. When the panel and housing materials are soft, the frequency corresponding to the first high-frequency valley is lower than when the panel and housing materials are stiff. It can be seen that a stiffer (harder) panel and housing material can increase the corresponding frequency value when high-frequency peaks / valleys appear. According to the description of FIG. 5, the frequency response from 1000 to 10,000 Hz is known to be particularly important for bone conduction earphones. Sharp peaks and valleys are not expected in this frequency range. The flatter the frequency response curve, the better the sound quality of the earphones. A stiffer (harder) material for the panels and housing in FIG. 7 may improve the sound quality of the earphone by lengthening the flat portion of the frequency curvature.

[0107] In some embodiments, the stiffness of different components (e.g., the housing, transmission components, driver, etc.) may be related to the Young's modulus, thickness, size, etc., of the material. The relationship between the stiffness of the housing and the material of the housing is described below with examples. In some embodiments, the housing may include a shell panel, a shell back panel, and housing sides. The shell panel, shell back panel, and housing sides may be formed of the same material or different materials. For example, the shell back panel and shell panel may be formed of the same material, while the housing sides may be formed of another material. In some embodiments, under certain conditions, the higher the Young's modulus of the housing material, the higher the stiffness of the housing. The peaks and valleys of the earphone's frequency response curve may shift to higher frequencies, which helps to adjust the high-frequency peaks and valleys to higher frequencies. In some embodiments, the Young's modulus of the housing material may be adjusted to adjust the peaks and valleys of the frequency response curve to higher frequencies. In some embodiments, a material with a specific Young's modulus may be used. The Young's modulus of the housing may be greater than 2000 MPa. Preferably, the Young's modulus of the housing may be greater than 4000 MPa. Preferably, the Young's modulus of the housing may be greater than 6000 MPa. Preferably, the Young's modulus of the housing may be greater than 8000 MPa. Preferably, the Young's modulus of the housing may be greater than 12000 MPa, more preferably, the Young's modulus of the housing may be greater than 15000 MPa. Even more preferably, the Young's modulus of the housing may be greater than 18000 MPa.

[0108] In some embodiments, by adjusting the rigidity of the housing, the high frequency peak-valley frequency in the frequency response curve of the bone conduction earphone may be 1000 Hz or higher. Preferably, the high frequency peak-valley frequency may be 2000 Hz or higher. Preferably, the high frequency peak-valley frequency may be 4000 Hz or higher. Preferably, the high frequency peak-valley frequency may be 6000 Hz or higher. More preferably, the high frequency peak-valley frequency may be 8000 Hz or higher. More preferably, the high frequency peak-valley frequency may be 10000 Hz or higher. More preferably, the high frequency peak-valley frequency may be 12000 Hz or higher. Even more preferably, the high frequency peak-valley frequency may be 14000 Hz or higher. Even more preferably, the high frequency peak-valley frequency may be 16000 Hz or higher. Even more preferably, the high frequency peak-valley frequency may be 18000 Hz or higher. Even more preferably, the high frequency peak-valley frequency may be 20000 Hz or higher. In some embodiments, by adjusting the rigidity of the housing, the high-frequency peak-valley frequencies in the frequency response curve of the bone conduction earphones may be outside the hearing range of the human ear. In some embodiments, by adjusting the rigidity of the housing, the high-frequency peak-valley frequencies in the frequency response curve of the earphones may be within the hearing range of the human ear. In some embodiments, if there are multiple high-frequency peaks / valleys, by adjusting the rigidity of the housing, one or more high-frequency peak / valley frequencies in the frequency response curve of the bone conduction earphones may be outside the hearing range of the human ear, while the remaining one or more high-frequency peak / valley frequencies may be within the hearing range of the human ear. For example, a second high-frequency peak may be outside the hearing range of the human ear, thereby causing the first high-frequency valley and the first high-frequency peak to be within the hearing range of the human ear.

[0109] In some embodiments, improving the rigidity of the housing may be achieved by changing the connection mode of the shell panel, shell back panel, and housing side to ensure greater overall housing rigidity. In some embodiments, the shell panel, shell back panel, and housing side may be formed as a whole. In some embodiments, the shell back panel and housing side may be formed as a whole. The shell panel and housing side may be directly secured together by adhesive, or may be secured together by snaps or welding. The adhesive may be a high-viscosity, high-hardness adhesive. In some embodiments, the shell panel and housing side may be formed as a whole, and the shell back panel and housing side may be directly secured together by adhesive, or may be secured together by snaps or welding. The adhesive may be a high-viscosity, high-hardness adhesive. In some embodiments, the shell panel, shell back panel, and housing side may be separate components. The three components may be fixedly connected together by adhesive, snaps, welding, or the like, or any combination thereof. For example, the shell panel and housing side may be connected together by adhesive, and the shell back panel and housing side may be connected together by snaps or welding. As another example, the shell back panel and housing side may be connected by adhesive, and the shell panel and housing side may be connected by snaps or welding.

[0110] In some embodiments, materials with different Young's moduli may be used and matched to improve the overall rigidity of the housing. In some embodiments, the shell panel, shell back panel, and housing sides may be formed of one material. In some embodiments, the shell panel, shell back panel, and housing sides may be formed of different materials, which may have the same or different Young's moduli. In some embodiments, the shell panel and shell back panel may be formed of the same material, while the housing sides may be formed of another material. The Young's moduli of the two materials may be the same or different. For example, the Young's modulus of the housing side material may be greater than that of the shell panel and shell back panel, or the Young's modulus of the housing side material may be less than that of the shell panel and shell back panel. In some embodiments, the shell panel and housing sides may be formed of the same material, while the shell back panel may be formed of another material. The Young's moduli of the two materials may be the same or different. For example, the Young's modulus of the shell back panel material may be greater than that of the shell panel and housing sides, or the Young's modulus of the shell back panel material may be less than that of the shell panel and housing sides. In some embodiments, the shell back panel and the housing side may be formed of the same material, and the shell panel may be formed of another material. The Young's moduli of the two materials may be the same or different. For example, the Young's modulus of the shell panel material may be greater than the Young's modulus of the shell back panel and the housing side, or the Young's modulus of the shell panel material may be less than the Young's modulus of the shell back panel and the housing side. In some embodiments, the shell panel, the shell back panel, and the housing side may all be different materials. The Young's moduli of the three materials may be the same or different, and may all be greater than 2000 MPa.

[0111] In some embodiments, by adjusting the rigidity of the vibration transmission sheet and the earphone fixing part, the two resonance peak frequencies in the low frequency range of the bone conduction earphone may both be less than 2000 Hz. Preferably, the two resonance peak frequencies in the low frequency range of the bone conduction earphone may be less than 1000 Hz. More preferably, the two resonance peak frequencies in the low frequency range of the bone conduction earphone may be less than 500 Hz.

[0112] In some embodiments, by adjusting the rigidity of each component of the bone conduction earphone (e.g., the housing, the housing bracket, the vibration transmission sheet, or the earphone fixing component), the peaks and valleys in the high frequency range can be adjusted to higher frequencies, and the low frequency resonance peaks can be adjusted to lower frequencies, thereby ensuring a frequency response curve platform in the range of 1000 Hz to 10,000 Hz, thereby improving the sound quality of the bone conduction earphone.

[0113] On the other hand, bone conduction earphones may cause sound leakage during vibration transmission. Sound leakage refers to the phenomenon where the volume of surrounding air changes due to vibrations of the internal components or the housing of the bone conduction earphone, causing the surrounding air to form compressed or sparse areas and propagate around, resulting in sound being transmitted to the surrounding environment, allowing people other than the wearer of the bone conduction earphone to hear the sound from the earphone. The present disclosure may provide a solution for reducing sound leakage from bone conduction earphones by changing the structure or rigidity of the housing.

[0114] In some embodiments, sound leakage from a bone conduction speaker may be further effectively reduced by a properly designed vibration-generating portion including a vibration transmission layer (not shown). Preferably, sound leakage may be reduced by providing holes on the surface of the vibration transmission layer. For example, the vibration transmission layer may be bonded to a panel, and the bonded area on the vibration transmission layer may be more convex than the non-bonded area on the vibration transmission layer. A cavity may be located below the non-bonded area. The non-bonded area of ​​the vibration transmission layer and the surface of the housing may each be provided with a sound introduction hole. Preferably, the non-bonded area having a portion of the sound introduction hole may not come into contact with the user. Meanwhile, the sound introduction hole effectively reduces the area of ​​the non-bonded area of ​​the vibration transmission layer, allowing air to pass between the inside and outside of the vibration transmission layer and reducing the difference in air pressure between the inside and outside, thereby reducing vibration in the non-bonded area. Meanwhile, the sound introduction hole may guide sound waves formed by internal air vibrations in the housing to the outside of the housing, thereby canceling out leaked sound waves formed by housing vibrations by pushing air out of the housing, thereby reducing the amplitude of the leaked sound waves.

[0115] In some embodiments, the angle between the direction of the driving force generated by the driving device and the direction of the panel may not be unique. Referring to Figures 8-16, methods of installing the driving device and the panel are illustrated in terms of different embodiments.

[0116] Embodiment 1 8 is a schematic diagram showing an axial cross-sectional structure of an exemplary bone conduction speaker according to the first embodiment of the present disclosure. As shown in FIG. 8, in some embodiments, the bone conduction speaker 800 may include a panel 801, a housing 802, a first transmission component 803, a coil 804, a vibration transmission sheet 805, and a magnetic system 806. The panel 801 and the housing 802 may form a sealed or semi-sealed cavity, and a driving device including the first transmission component 803, the coil 804, the vibration transmission sheet 805, and the magnetic system 806 may be located in the cavity.

[0117] In some embodiments, both the coil 804 and the magnetic system 806 may have a ring structure. In some embodiments, the coil 804 and the magnetic system 806 may have axes that are parallel to each other. The axis of the driver refers to the axis of the coil 804 and / or the magnetic system 806. The axis of the driver and a normal to a region on the panel that contacts or is adjacent to the user's body may form an angle θ (0°<θ<90°). Specifically, the axis of the driver and a normal to a region on the panel that contacts or is adjacent to the user's body may form an angle θ. More description of the spatial relationship between the axis of the coil 804 or the magnetic system 806 and its normal may be found elsewhere in this disclosure (see, for example, FIG. 3 and its description).

[0118] In some embodiments, a portion of the first transmission component 803 may have a ring structure that matches the structure of the coil 804. The ring structure may be mechanically connected to one end surface of the coil 804, and another portion of the first transmission component 803 may be a connecting rod mechanically connected to the panel and / or housing. All or a portion of the coil 804 may be sleeved in the magnetic gap of the magnetic system 806. All or a portion of the coil 804 may be sleeved in an annular groove of the magnetic system 806. In some embodiments, the annular end surface of the magnetic system 806 may be mechanically connected to the outer edge of the vibration transmission sheet 805. The first transmission component 803 may pass through the middle region of the vibration transmission sheet 805 and be fixedly connected to the vibration transmission sheet 805.

[0119] After being energized, the coil 804 generates an ampere of force and vibration within the magnetic field generated by the magnetic system 806, and the vibration of the coil 804 may be transmitted to the panel 801 through the first transmission part 803. The vibration generated by the reaction force received by the magnetic system 806 may be transmitted directly to the first transmission part 803 through the vibration transmission sheet 805 and further to the panel 801. The vibration of the coil 804 and the vibration of the magnetic system 806 may be transmitted to the skin and bones of the human body through the panel 801, thereby allowing people to hear the sound. It may be understood that the vibration transmission sheet is directly connected to the magnetic system 806 and the first transmission part 803, and therefore the vibration generated by the magnetic system 806 may be transmitted directly to the panel through the first transmission part 803. Furthermore, the vibrations generated by the coil 804 and the vibrations generated by the magnetic system 806 may form a composite vibration that is transmitted to the panel 801, and then the composite vibration may be transmitted through the panel 801 to the skin and bones of the human body, thereby allowing people to hear bone-conducted sound.

[0120] Embodiment 2 9A is a schematic diagram showing an axial cross-sectional structure of an exemplary bone conduction speaker according to a second embodiment of the present disclosure. The bone conduction speaker 900a may include a panel 901, a housing 902, a first transmission component 903, a coil 904, a vibration transmission sheet 905, a second transmission component 906, and a magnetic system 907. The first transmission component 903 may be a hollow cylinder, and one end surface of the first transmission component 903 may be mechanically connected to the panel 901, while the other end surface of the first transmission component 903 may be mechanically connected to one end of the coil 904. All or a portion of the coil 904 may be sleeved in an annular groove or magnetic gap of the magnetic system 907. It should be understood that both the coil 904 and the magnetic system 907 may have ring structures. In some embodiments, the coil 904 and the magnetic system 907 may have axes parallel to each other. More explanation of the spatial relationship between the axis of the coil 904 or magnetic system 907 and the normal to the area on the panel that contacts or is adjacent to the user's body may be found elsewhere in this disclosure (see, for example, FIG. 3 and its description). The center or near-center area of ​​the magnetic system 907 is mechanically connected to one end of the second transmission component 906. The other end of the second transmission part 906 may be mechanically connected to a central region or a region near the center of the vibration transmission sheet 905. The outer edge of the vibration transmission sheet 905 may be mechanically connected to the inside of the flange of the first transmission part 903. The connection method may include, but is not limited to, clamp connection, hot pressing connection, bonding connection, injection molding connection, etc.

[0121] In this embodiment, after being energized, the coil 904 generates an ampere of force and vibration within the magnetic field generated by the magnetic system 907, and the vibration of the coil 904 may be transmitted to the panel 901 through the first transmission part 903. The vibration generated by the reaction force received by the magnetic system 907 may be transmitted to the panel 901 through the second transmission part 906, the vibration transmission sheet 905, and the first transmission part 903. The vibration of the coil 904 and the vibration of the magnetic system 907 may be transmitted to the skin and bones of the human body through the panel 901, thereby enabling people to hear the sound. In short, the vibration generated by the coil 904 and the vibration generated by the magnetic system 907 may form a composite vibration that is transmitted to the panel 901, and the composite vibration may then be transmitted to the skin and bones of the human body through the panel 901, thereby enabling people to hear the bone-conducted sound.

[0122] The embodiment shown in Figure 9A may be different from the embodiment shown in Figure 8. As shown in Figure 9A, by changing the first transmission component from a connecting rod to a hollow cylindrical structure, the combination of the first transmission component and the coil may be more complete and the structure may be more stable. At the same time, the frequency of the speaker's higher-order mode (i.e., the vibrations at different points on the speaker do not coincide) may be increased and the low-frequency resonance peak of the bone conduction speaker's frequency response curve may be moved to a lower frequency, thereby widening the flat area of ​​the frequency response curve and improving the sound quality of the speaker.

[0123] 9B is a schematic diagram illustrating an exploded structure of an exemplary bone conduction speaker according to Embodiment 2 of the present disclosure. FIG. 9C is a schematic diagram illustrating a longitudinal cross-sectional structure of the exemplary bone conduction speaker in FIG. 9B according to some embodiments of the present disclosure. The structure of the bone conduction speaker shown in FIG. 9B and FIG. 9C may correspond to the structure shown in FIG. 9A.

[0124] As shown in FIG. 9B , the bone conduction speaker 900b may include a silicone part 910 attached to the vibration plate and surface, a bracket and vibration transmission sheet 911, a coil 912, a connecting part 913, a bolt and nut assembly 914, an upper magnet 915, a magnetically conductive plate 916, a lower magnet 917, a magnetically conductive cover 918, a multifunction key PCB 919, a silicone multifunction button 920, a speaker shell 921, an earhook multifunction button 922, and an earhook 923. As shown in FIG. 9C , the silicone part 910 attached to the vibration plate and surface may further include a silicone part 9101 and a vibration plate 9102 attached to the surface. The bracket and vibration transmission sheet 911 may further include a bracket 9111 and a vibration transmission sheet 9112. The bolt and nut assembly 914 may further include a bolt 9141 and a nut 9142. The vibration plate 9102 may be functionally equivalent to the panel described above, and the silicone 9101 attached to the surface may be equivalent to the soft material covering the panel. It may be understood that the silicone 9101 attached to the surface may not be an essential part. In some embodiments, the silicone 9101 attached to the surface may be omitted. The bracket 9111 may correspond to the first transmission part described above. The connecting part 913 may correspond to the second transmission part described above. The speaker shell 921 may be equivalent to the housing described above.

[0125] As shown in FIG. 9C , the vibration plate and the silicone part 910 attached to the surface may be combined with the speaker shell 921 to form a sealed or semi-sealed cavity for housing the magnetic system, transmission components, and other components. The magnetically conductive cover 918 may have a concave structure, specifically including a bottom plate and side walls. The upper magnet 915, the magnetically conductive plate 916, and the lower magnet 917 may be stacked from top to bottom on the bottom plate of the magnetically conductive cover 918. The upper magnet 915, the magnetically conductive plate 916, the lower magnet 917, and the magnetically conductive cover 918 may each have a through hole and be assembled together with a bolt and nut assembly 914 to form the magnetic system. A magnetic gap may be formed between the magnetically conductive cover 918 and the upper magnet 915, the magnetically conductive plate 916, and the lower magnet 917 attached to the bottom plate. The coil 912 may be partially or entirely disposed within the magnetic gap. As shown in FIGS. 9D and 9E , the bracket 9111 may have a ring structure with a non-uniform thickness. Specifically, one side may be thicker than the other. One end of the bracket 9111 may correspond in size to the coil 912 and be mechanically connected to one end of the coil 912, while the other end of the bracket 9111 may be adjacent to or mechanically connected to the silicone part 910 attached to the vibration plate and surface. The structure of the bracket 9111, with one side thicker than the other, may tilt the driver relative to the silicone part 910 attached to the vibration plate and surface, thereby ensuring that the axis of the driver (or the direction of the driving force) and the normal to the contact surface (the surface that contacts human skin) of the silicone part 910 attached to the surface form an angle θ. The connecting part 913 may connect the upper magnet 915 of the magnetic system to the vibration transmission sheet 9112 and simultaneously function as a vibration transmitter. Specific connection methods may include, but are not limited to, bolted connections, bonded connections, and welded connections. The edges of the vibration transmission sheet 9112 may be snapped onto the inside of the bracket 9111. The bracket 9111 may also perform the function of transmitting the vibrations of the coil and the vibrations of the magnetic system to the vibration plate and the silicone part 910 attached to the surface.The outer edge of the bracket may be snapped into a groove or limiting slot in the inner wall of the speaker shell 921 and secured within the cavity, allowing the bracket to provide transmission while also suspending and supporting the entire driver.

[0126] 9D and 9E are schematic diagrams illustrating the structure of a bracket in an exemplary bone conduction speaker according to some embodiments of the present disclosure. As shown in FIGS. 9D and 9E , by way of example only, the bracket 9111 may have an annular body 91111. The body may be an annular sheet structure, and an annular facade 91112 conforming to the shape of the body may be provided on the body. One side of the facade 91112 may be lower than the other side (e.g., facade A side is lower than facade B side). The transition between the higher and lower sides may be achieved via connecting portions C and D, whose heights change continuously, or via connecting portions whose heights change discontinuously. For example, connecting portions C and D may be configured with a step-like structure whose heights change discontinuously. Note that side A, side B, connecting portion C, and connecting portion D may be considered four distinct parts of the facade 91112 and may be integrally formed with each other without any apparent structural boundaries. Side A, side B, connecting portion C, and connecting portion D may also be structurally independent of each other and assembled together by additional connecting methods. Specific connecting methods may include, but are not limited to, bonding, welding, hot melt, etc. A bracket 9111 may be used to connect the coil to the silicone part 910 attached to the vibration plate and the surface to achieve vibration transmission. Specifically, the lower end surface of the bracket body 91111 may be fixedly connected to the upper end surface of the coil, and the upper end surface of the facade 91112 may be adjacent to or mechanically connected to the silicone part 910 attached to the vibration plate and the surface (see FIG. 9C ). In some embodiments, the distance between the vibration plate, the silicone part 910 attached to the surface, and the driver (e.g., the coil) may be relatively long, which may increase the height of the facade. If the facade 91112 is thin, it has low strength and may be easily damaged. If the facade 91112 is thick, it may affect transmission and sound quality. In some embodiments, some reinforcements 91113 may be provided on the outside or inside of the facade 91112, which may ensure the strength of the facade 91112 without affecting the sound quality.In some embodiments, the stiffener 91113 may be a smaller facade perpendicular to the facade 91112, one end of which may be mechanically connected to the main body 91111 and the other end of which may be mechanically connected to the facade 91112. The connection method may include, but is not limited to, a bonded connection, a welded connection, thermoplastic molding, integral molding, etc. In some embodiments, the stiffener 91113 may also be a short strut. The strut may be supported diagonally between the facade and the main body. One end of the strut may be mechanically attached to the main body 91111 and the other end may be mechanically connected to the facade 91112. The connection method may include, but is not limited to, a bonded connection, a welded connection, thermoplastic molding, integral molding, etc. Embodiment 3

[0127] FIG. 10 is a schematic diagram showing the axial cross-sectional structure of an exemplary bone conduction speaker according to a third embodiment of the present disclosure. Compared with the bone conduction speaker 900, the difference between the bone conduction speaker 1000 and the bone conduction speaker 900 may be the installation position and length of the first transmission part 1003. The first transmission part 1003 may include multiple connecting rods or connecting posts. One end of some of the connecting rods may be mechanically connected to the panel 1001. One end of other connecting rods may be mechanically connected to the first side 1002 of the housing, and the other end of each connecting rod may be mechanically connected to one end surface of the coil 1004. That is, each connecting rod may be distributed between the coil and the panel and / or housing along the coil 1004, and the connecting rods may be distributed at equal intervals or at different intervals. As a variation of this embodiment, the first transmission part 1003 may also be designed as a hollow cylinder like the first transmission part 903, and its cross section may be adapted to the size and shape of the coil. A first end surface of the first transmission part 1003 may be mechanically connected to one end of the coil, a portion of the second end surface of the first transmission part 1003 may be mechanically connected to the panel 1001, and another portion may be mechanically connected to the housing 1002.

[0128] Compared to the bone conduction speaker 900, the length of the first transmission part 1003 of the bone conduction speaker 1000 may be shorter, which may further increase the frequency at which the speaker generates higher modes (i.e., the vibrations of different points on the speaker do not match).

[0129] Embodiment 4 FIG. 11 is a schematic diagram showing an axial cross-sectional structure of an exemplary bone conduction speaker according to a fourth embodiment of the present disclosure. As shown in FIG. 11 , the bone conduction speaker 1100 may include a driver 1101, a transmission component 1102, a panel 1103, and a housing 1105. The transmission component 1102 may include structures such as a vibration transmission sheet, a connecting rod, and a connecting post. The transmission component 1102 may be mechanically connected to the driver 1101 and the panel 1103 as a transmission path for transmitting the vibration or driving force generated by the driver 1101 to the panel 1103. In some embodiments, the distance between the panel and the driver is relatively long, so the length of the transmission path needs to be long. Furthermore, the length of the transmission component needs to be long. For example, the length of the connecting rod or connecting post needs to be long. If the structure of the transmission component is thin, its strength will be relatively low and it may be damaged by long-term vibration. If the structure of the transmission component is made thicker to solve this problem, it may affect the transmission of vibration and thus the sound quality. In some embodiments, additional reinforcements 1104 may be provided on the surface of the transmission component to increase the strength of the transmission component and have a small impact on the structure of the transmission component. In some embodiments, the reinforcements 1104 may include facades, ridges, struts, etc. The connection method between the reinforcements 1104 and the transmission component 1102 may include, but is not limited to, bonded connections, welded connections, thermoplastic molding, integral molding, etc. In some embodiments, multiple reinforcements 1104 may be provided on the surface of the transmission component. In the case of annular transmission components, the reinforcements may be distributed at equal or uneven intervals around the circumference of the transmission component. More description of reinforcements may be found elsewhere in this disclosure (see, for example, Figures 9D and 9E and their descriptions).

[0130] Compared to other embodiments, the bone conduction speaker 1100 shown in Figure 11 may have reinforcement 1104 added to the transmission component. While increasing the strength of the transmission component, the frequency at which the speaker produces higher modes (i.e., vibrations at different points on the speaker do not match) may also be increased, which may result in better sound.

[0131] Embodiment 5 12 is a schematic diagram showing an axial cross-sectional structure of an exemplary bone conduction speaker according to embodiment 5 of the present disclosure. As shown in FIG. 12, in some embodiments, one end of a first transmission component 1203 of a bone conduction speaker 1200 may be mechanically connected to the bottom surface of a housing 1202, i.e., the entire driving device may be fixed to the housing 1202 at an angle relative to the panel.

[0132] Specifically, both the housing 1202 and the panel 1201 may have great hardness and may be integrally formed or connected via a connecting medium having a relatively high rigidity. After energization, the vibration generated by the coil 1204 and the vibration generated by the magnetic system 1207 may form a composite vibration that is transmitted to the housing 1202 and then to the panel 1201. The composite vibration may be transmitted to the skin and bones of the human body through the panel 1201, allowing people to hear bone-conducted sound.

[0133] Embodiment 6 FIG. 13 is a schematic diagram showing an axial cross-sectional structure of an exemplary bone conduction speaker according to a sixth embodiment of the present disclosure. As shown in FIG. 13 , in some embodiments, a bone conduction speaker 1300 may include a housing 1302, a panel 1301 provided independently of the housing, and a driving device. The driving device may include a first transmission component 1303, a coil 1304, a vibration transmission sheet 1305, a second transmission component 1306, and a magnetic system 1307. The housing 1302 may include a first housing 13021 and a third transmission component 13022. The first housing 13021 may be a rectangular parallelepiped having a cavity. In some embodiments, the first housing 13021 may be a closed cylinder, a sphere having a cavity, or the like. The driving device may be located within the cavity, and the internal structure of the driving device may be any of the above-described embodiments.

[0134] The upper side of the first housing 13021 may be mechanically connected to the upper side of the panel 1301 via the third transmission part 13022, and the lower side of the first housing 13021 may be directly connected to the lower side of the panel 1301. The method of connecting the first housing 13021 and the panel 1301 is not limited to the above method. For example, the lower side of the first housing 13021 may be mechanically connected to the lower side of the panel 1301 via the third transmission part 13022, and the upper side of the first housing 13021 may be directly connected to the upper side of the panel 1301. As another example, only the central region of the first housing 13021 may be mechanically connected to the panel via the third transmission part. The third transmission part may be a rod-shaped, plate-shaped, or hollow columnar structure.

[0135] In this embodiment, after being energized, the coil 1304 generates an ampere force and vibration within the magnetic field generated by the magnetic system 1307, and the vibration of the coil 1304 may be transmitted to the first housing 13021 through the first transmission part 1303. The first housing 13021 may transmit the vibration to the panel 1301 via the third transmission part 13022 or directly. The vibration generated by the reaction force received by the magnetic system 1307 may be transmitted to the first housing 13021 through the connection between the second transmission part 1306 and the vibration transmission sheet 1305. The first housing 13021 may transmit the vibration to the panel 1301 via the third transmission part 13022 or directly. The vibration of the coil 1304 and the vibration of the magnetic system 1307 may be transmitted to the skin and bones of the human body through the panel 1301, allowing people to hear the sound. In short, the vibration generated by the coil 1304 and the vibration generated by the magnetic system 1307 form a composite vibration, which may be first transmitted to the first housing 13021 and then transmitted to the panel 1301 directly or through the third transmission part 13022. The composite vibration may be transmitted to the skin and bones of the human body through the panel 1301, allowing people to hear bone-conducted sound.

[0136] Embodiment 7 14 is a schematic diagram showing an axial cross-sectional structure of an exemplary bone conduction speaker according to a seventh embodiment of the present disclosure. As shown in FIG. 14, a bone conduction speaker 1400 may have a first transmission path and a second transmission path that are independent of each other. Specifically, the first transmission path may include a first transmission component 1403. The transmission components of the second transmission path may include a vibration transmission sheet 1405 and a second transmission component 1406. The bone conduction speaker 1400 having the first transmission path and the second transmission path that are independent of each other may mean that the two transmission paths do not have any transmission components in common.

[0137] As shown in FIG. 14 , a bone conduction speaker 1400 may include a panel 1401, a housing 1402, a first transmission part 1403, a coil 1404, a vibration transmission sheet 1405, a second transmission part 1406, and a magnetic system 1407. The panel 1401 and the housing 1402 may form a sealed or semi-sealed cavity, and a driver including the first transmission part 1403, the coil 1404, the vibration transmission sheet 1405, the second transmission part 1406, and the magnetic system 1407 may be located within the cavity. An axis of the driver and a normal to a region on the panel that contacts or is adjacent to the user's body may form an angle θ (0°<θ<90°). The bottom surface of the magnetic system 1407 may be mechanically connected to the vibration transmission sheet 1405 via the second transmission part 1406, and the outer edge of the vibration transmission sheet 1405 may be mechanically connected to the housing 1402. For example, the outer edge of the vibration transmission sheet 1405 may be mechanically connected to the bottom of the housing 1402 or to the side of the housing 1402, or one portion may be mechanically connected to the bottom of the housing 1402 and the other portion may be mechanically connected to the side of the housing 1402.

[0138] In this embodiment, after being energized, the coil 1404 generates a force of amperes and vibrations within the magnetic field generated by the magnetic system 1407, and the vibrations of the coil 1404 may be transmitted to the panel 1401 through the first transmission part 1403. The vibrations generated by the reaction force received by the magnetic system 1407 may be transmitted to the bottom and side of the housing 1402 through the second transmission part 1406 and the vibration plate 1405. The housing may transmit the vibrations of the magnetic system 1407 to the panel 1401. Finally, the vibrations of the coil 1404 and the magnetic system 1407 may be transmitted to the skin and bones of the human body through the panel 1401, allowing people to hear the sound. It may be understood that the magnetic system and the housing 1402 may be soft-connected because the vibration transmission sheet is directly connected to the housing 1402. The vibrations generated by the magnetic system 1407 may be directly transmitted to the bottom and one side of the housing 1402. The vibrations generated by the coil 1404 and the vibrations generated by the magnetic system 1407 may form a composite vibration that is transmitted to the panel 1401. When the composite vibration is transmitted through the panel 1401 to the skin and bones of the human body, people can hear bone-conducted sound.

[0139] Embodiment 8 FIG. 15 is a schematic diagram showing the axial cross-sectional structure of an exemplary bone conduction speaker according to an eighth embodiment of the present disclosure. The bone conduction speaker 1500 shown in FIG. 15 may include a dual vibration transmission sheet structure. The low-frequency range of the speaker's vibration frequency response curve may have an additional peak, thereby making the speaker's low-frequency response more sensitive and improving sound quality. Specifically, as shown in FIG. 15, the bone conduction speaker 1500 may include a panel 1501, a housing 1502, a first transmission component 1503, a coil 1504, a first vibration transmission sheet 1505, a second vibration transmission sheet 1506, a second transmission component 1507, and a magnetic system 1508. The connection method between the panel 1501, the first transmission component 1507, the first vibration transmission sheet 1505, the second transmission component 1507, and the magnetic system 1508 may be the same as that shown in FIG. 9. An edge of the second vibration transmission sheet 1506 may be mechanically connected to the open end surface of the housing 1502. The first transmission part 1503 may pass through a central region of the second vibration transmission sheet 1506 and be fixedly connected to the second vibration transmission sheet 1506. The central axial surface of the second vibration transmission sheet 1506 may be snapped onto the solid cylindrical body of the first transmission part 1503.

[0140] The operating principle of the bone conduction speaker 1500 in this embodiment may be as follows: After being energized, the coil 1504 generates a force and vibration in the magnetic field generated by the magnetic system 1508, and the vibration of the coil 1504 may be directly transmitted to the panel 1501 through the first transmission part 1503. The vibration generated by the reaction force received by the magnetic system 1508 may be transmitted to the panel 1501 through the second transmission part 1507 and the first vibration transmission sheet 1505. The vibration of the housing 1502 may be transmitted to the panel 1501 through the second vibration plate. Then, the vibration of the coil 1504 and the vibration of the magnetic system 1508 may be transmitted to the skin and bones of the human body through the panel 1501, allowing people to hear the sound. It may be understood that a soft connection between the panel 1501 and the housing 1502 may be realized through the second vibration transmission sheet 1506. The vibrations generated by the coil 1504 and the vibrations generated by the magnetic system 1508 may form a composite vibration that is transmitted to the panel 1501 and the housing 1502. The composite vibration may then be transmitted through the panel 1501 to the skin and bones of the human body, allowing people to hear bone-conducted sound.

[0141] Embodiment 9 FIG. 16 is a schematic diagram showing an axial cross-sectional structure of an exemplary bone conduction speaker according to a ninth embodiment of the present disclosure. As shown in FIG. 16 , in yet another embodiment, a bone conduction speaker 1600 may include a panel 1601, a housing 1602, and two drivers 1605 and 1606. The panel 1601 and the housing 1602 may form a sealed or semi-sealed cavity, and the two drivers 1605 and 1606 may be located within the cavity. The drivers in this embodiment may be the drivers in the previous embodiments of the present disclosure. The driver 1605 may be mechanically connected to the panel 1601 via a first transmission part 1603. The driver 1606 may be mechanically connected to a partition plate provided within the cavity via a second transmission part 1604. A certain angle may be formed between the driver 1605 and the driver 1606. In some embodiments, the driver 1606 may be directly connected to the panel or housing via a second transmission part 1604 bent at a right angle. Note that in some embodiments, the axis of the driver 1605 may not be parallel to the normal to the panel, and the axis of the driver 1606 may not be perpendicular to the normal to the panel. The positions of the two drivers relative to the panel may be such that the resulting line of the driving forces generated by the two drivers and the normal to the area on the panel that contacts or is adjacent to the user's body form an angle θ (0°<θ<90°). Furthermore, it may be understood that the number of drivers may also be three, four, or more. By adjusting the position of each driver within the cavity, the resulting line of the driving forces generated by each driver and the normal to the area on the panel that contacts or is adjacent to the user's body may form an angle θ (0°<θ<90°).

[0142] In this embodiment, the driving force of driver 1605 may be parallel to the normal of the area on the panel that is in contact with or adjacent to the user's body. The driving force of driver 1606 may be perpendicular to the normal of the area on the panel that is in contact with or adjacent to the user's body. By simultaneously vibrating the two drivers and transmitting two types of vibration to the panel, the combined vibration is transmitted through panel 1601 to the skin and bones of the human body, allowing people to hear bone-conducted sound.

[0143] The present disclosure also provides bone conduction earphones. During use, the earphone holder / earphone strap may secure the bone conduction speaker to a specific part of the user (e.g., the head) and provide a clamping force between the vibration unit and the user. The contact surface may be connected to a driver to maintain contact with the user and transmit sound to the user through vibration. Assuming that the bone conduction speaker has a symmetrical structure and the driving forces provided by the two drivers on both sides are the same but in opposite directions, the center point of the earphone holder / earphone strap may be selected as the equivalent fixed end. If the bone conduction speaker can provide stereo sound, that is, if the magnitudes of the instantaneous driving forces provided by the two transducers are different, or if the bone conduction speaker has an asymmetrical structure, other points or regions inside or outside the earphone holder / earphone strap may be selected as the equivalent fixed end. As used herein, the term "fixed end" may be considered as the equivalent end at which the position of the bone conduction speaker is relatively fixed during the vibration generation process. The fixed end and the vibration unit may be connected via an earphone holder / strap. The transmission relationship may be related to the clamping force provided by the earphone holder / strap, and the clamping force may depend on the physical characteristics of the earphone holder / strap. Preferably, changing the physical characteristics, such as the clamping force provided by the earphone holder / strap, or the quality of the earphone holder / strap, may change the sound transmission efficiency of the bone conduction speaker, thereby affecting the system's frequency response in a specific frequency range. For example, earphone holders / straps made of higher-strength materials and earphone holders / straps made of lower-strength materials may provide different clamping forces. Alternatively, changing the structure of the earphone holder / strap, such as adding an auxiliary device that provides elasticity to the earphone holder / strap, may change the clamping force, thereby affecting the sound transmission efficiency. When worn, changing the size of the earphone holder / strap may also affect the magnitude of the clamping force.The clamping force may increase with the distance between the vibrating units on either end of the earphone holder / earphone strap.

[0144] To obtain earphone holders / earphone straps that meet specific clamping force requirements, those skilled in the art may select materials with different stiffnesses and elastic moduli to manufacture the earphone racks / earphone straps or adjust the size of the earphone racks / earphone straps. It should be noted that the clamping force of an earphone holder / earphone strap not only affects the sound transmission efficiency but also the user's sound experience in the low-frequency range. The clamping force described herein may refer to the pressure between the contact surface and the user. Preferably, the clamping force may be in the range of 0.1 N to 5 N. More preferably, the clamping force may be in the range of 0.2 N to 4 N. More preferably, the clamping force may be in the range of 0.2 N to 3 N. More preferably, the clamping force may be in the range of 0.2 N to 1.5 N, and even more preferably, the clamping force may be in the range of 0.3 N to 1.5 N.

[0145] It should be noted that the above-described embodiments of the bone conduction speaker may be merely examples, and the components and structures described in these embodiments should not be construed as limitations of the present disclosure. The components, shapes, structures, and connection methods in these embodiments may be combined. For example, the reinforcement member in FIG. 11 may be applied to any of the embodiments shown in FIGS. 9 to 16. The first transmission component 903 of the bone conduction speaker 900a in FIG. 9 may also be connected to the panel and housing at the same time as the first transmission component 1003 of the bone conduction speaker 1000, or may be connected to the rear of the housing as in the bone conduction speaker 1200.

[0146] 17 is a flowchart illustrating a method for installing a bone conduction speaker according to some embodiments of the present disclosure. Method 1700 may be a step included in installing a bone conduction speaker according to certain embodiments of the present disclosure.

[0147] In 1710, a transmission connection between the panel and the driver may be established. In some embodiments, the driver may be connected to the panel using transmission and connection components, such as a vibration transmission sheet. In addition to a structural connection, the transmission components may also serve to transmit vibrations. Specifically, the driver may include a coil and a magnetic system. Vibrations of the coil and the magnetic system may be transmitted to the panel and / or housing via different paths. For example, vibrations of the coil may be transmitted to the panel and / or housing through a first transmission path, and vibrations of the magnetic system may be transmitted to the panel and / or housing through a second transmission path. The first transmission path may include a first transmission component. The second transmission path may include a second transmission component, a vibration transmission sheet, and the first transmission component. The first transmission component may be a connecting post or a connecting rod. The second transmission component may be a connecting post or a connecting rod.

[0148] In some embodiments, the bone conduction speaker may connect the driving part of the panel to the driving device to transmit vibrations generated by the driving device to the panel, thereby further transmitting the vibrations to the human body through the panel attached to the human body. The transmission connection between the panel and the driving device effectively transmits the vibration signal generated by the driving device, so that the human body may receive the signal. In some embodiments, the panel, the transmission part, and the driving device are generally made of rigid materials and are firmly connected to each other to improve the quality of the transmitted audio signal.

[0149] In 1720, the relative positions of the driver and the panel may be set so that the line along which the driving force generated by the driver lies is not parallel to the normal to the panel. Specifically, the relative positions of the driver and the panel may be set according to the various embodiments described above. The installation method employed may include changing the structure of the transmission components. For example, the transmission components may be set in a structure where one side is lower than the other, thereby ensuring that the line along which the driving force lies is not parallel to the normal to the panel. The installation method employed may also include improving the structure of the panel or the housing to achieve a technical objective. For example, a platform inclined relative to the panel may be set within the housing, and the driver may be set on the platform. As another example, the driver may be set horizontally within the housing, and the panel may be inclined to cover the housing. As long as the driver can be inclined relative to the panel so that the line along which the driving force lies is not parallel to the normal to the area on the panel that contacts or is adjacent to the user's body, any method may be applied to the present disclosure, and the present disclosure is not limited thereto.

[0150] It should be noted that there is no required sequence for the two steps of installing the bone conduction speaker. The order of the two steps may be reversed. In some embodiments, the two steps may not be completely separate processes, i.e., the two steps may be performed simultaneously. For example, when the driver is connected to the panel, the relative positions of the two are adjusted.

[0151] Having thus described the basic concepts, it will be apparent to those skilled in the art after reading this detailed disclosure that the above detailed disclosure has been presented by way of example only and is not limiting. Although not expressly stated herein, various changes, improvements, and modifications are contemplated and possible by those skilled in the art. These changes, improvements, and modifications are intended to be suggested by this disclosure and are within the spirit and scope of the exemplary embodiments of the present disclosure.

[0152] Furthermore, certain terms are used to describe embodiments of the present disclosure. For example, the terms "one embodiment," "embodiment," and / or "some embodiments" mean that a particular feature, structure, or characteristic described in connection with this embodiment is included in at least one embodiment of the present disclosure. Accordingly, it is emphasized and understood that references to "an embodiment" or "one embodiment" or "alternative embodiments" more than once in various parts of this specification do not necessarily all refer to the same embodiment. Furthermore, particular features, structures, or characteristics may be combined as appropriate in one or more embodiments of the present disclosure.

[0153] Moreover, as will be appreciated by those skilled in the art, aspects of the present disclosure may be illustrated and described herein in any of a number of patentable varieties or contexts, including any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof. Accordingly, aspects of the present disclosure may be implemented entirely in hardware, entirely in software (including firmware, resident software, microcode, etc.), or a combination of software and hardware, which implementations may be collectively referred to herein generally as "units," "modules," or "systems." Furthermore, aspects of the present disclosure may take the form of a computer program product embodied in one or more computer-readable medium(s) having computer-readable program code embodied therein.

[0154] Furthermore, unless expressly recited in the claims, the use of a described order, numbers, letters, or other designations of processing elements or sequences herein is not intended to limit the order of the processes and methods of the present application. While the above disclosure discusses various examples of what are presently considered to be various useful embodiments of the present disclosure, it should be understood that such details are provided for illustrative purposes only, and that the appended claims are not limited to the disclosed embodiments, but rather are intended to cover modifications and equivalent arrangements within the spirit and scope of the disclosed embodiments. For example, implementations of the various components described above may be embodied in hardware devices, or may be implemented as software-only solutions, e.g., installed on existing servers or mobile devices.

[0155] Similarly, in the foregoing description of embodiments of the present disclosure, it should be understood that various features are grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure to aid in understanding one or more of the various inventive embodiments. However, this method of disclosure should not be interpreted as reflecting an intention that the claimed subject matter requires more features than are expressly recited in each claim. Rather, embodiments of the present invention may encompass less than all features of a single foregoing disclosed embodiment.

[0156] In some embodiments, numbers expressing quantities or properties used to describe and claim particular embodiments of the present application should be understood to be modified in some instances by the terms "about," "approximately," or "substantially." For example, unless otherwise specified, "about," "approximately," or "substantially" can represent a variation of ±1%, ±5%, ±10%, or ±20% of the recited value. Thus, in some embodiments, the numerical parameters set forth in the specification or appended claims are approximations that may vary depending on the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad ranges of some embodiments of the present application are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible.

[0157] Finally, it should be understood that the embodiments of the present application disclosed herein are illustrative of the principles of the embodiments of the present application. Other modifications may be adopted within the scope of the present application. Thus, by way of example, alternative configurations of the embodiments of the present application may be utilized in accordance with the contents of this specification. Thus, the embodiments of the present application are not limited to those precisely as shown and described. [Explanation of symbols]

[0158] 101 Drive unit 102 Transmission parts 103 Bone, Panel 104 Housing 300 Bone conduction speaker Panel 301 302 Panel, housing 303 First transmission part, transmission part 304 coil 305 Vibration Transmission Sheet 306 Second transmission part 307 Magnetic Systems 310 Skeleton 320 skin 510 Resonance Peak 520 Resonance Peak 530 First High Frequency Valley 540 First high frequency peak 550 Second high frequency peak 800 Bone Conduction Speaker 801 Panel 802 Housing 803 First Transmission Part 804 Coil 805 Vibration Transmission Sheet 806 Magnetic Systems 900 Bone conduction speaker 901 Panel 902 Housing 903 First Transmission Part 904 Coil 905 Vibration Transmission Sheet 906 Second transmission part 907 Magnetic System 910 Silicone Parts 911 Vibration Transmission Sheet 912 Coil 913 Connection parts 914 Nut Assembly 915 Upper magnet 916 Magnetic Conduction Plate 917 Lower Magnet 918 Magnetic Conduction Cover 919 Multifunction Key PCB 920 Multi-function Button Silicone 921 Speaker Shell 922 Earhook Multifunction Button 923 Ear Hook 1000 Bone Conduction Speaker 1001 Panel 1002 first side, housing 1003 First transmission part 1004 Coil 1100 Bone conduction speaker 1101 Drive unit 1102 Transmission parts 1103 Panel 1104 Reinforcement material 1105 Housing 1200 Bone conduction speaker 1201 Panel 1202 Housing 1203 First Transmission Part 1204 Coil 1207 Magnetic Systems 1300 Bone conduction speaker 1301 Panel 1302 Housing 1303 First Transmission Part 1304 Coil 1305 Vibration transmission sheet 1306 Second Transmission Part 1307 Magnetic Systems 1400 Bone conduction speaker 1401 Panel 1402 Housing 1403 First Transmission Part 1404 Coil 1405 Vibration transmission sheet, vibration plate 1406 Second transmission part 1407 Magnetic Systems 1500 Bone conduction speaker 1501 Panel 1502 Housing 1503 First Transmission Part 1504 Coil 1505 First vibration transmission sheet 1506 Second vibration transmission sheet 1507 Second transmission part, first transmission part 1508 Magnetic Systems 1600 Bone conduction speaker 1601 Panel 1602 Housing 1603 First transmission part 1604 Second transmission part 1605 Drive unit 1606 Drive unit 1700 methods 3071 First magnetic part 3072 First magnetic conductive part 3073 Second magnetic conductive part 9101 Silicone 9102 Vibration Plate 9111 Bracket 9112 Vibration Transmission Sheet 9141 Bolt 9142 Nut 13021 First Housing 13022 Third transmission part 91111 Main body, bracket main body 91112 Facade 91113 Reinforcement material

Claims

1. A bone conduction speaker, the bone conduction speaker comprising: a driver configured to generate a driving force, the driver including a coil and a magnetic system; a panel communicatively connected to the driver, all or a portion of the panel configured to contact a body of a user to conduct sound; a housing for accommodating the drive device; It is equipped with A bone conduction speaker, characterized in that the two resonance peaks of the bone conduction speaker are less than 500 Hz.

2. the coil is connected to the panel and / or the housing via a connecting part; the magnetic system is connected to the panel and / or the housing via a vibration transmission sheet; 2. The bone conduction speaker according to claim 1, wherein the rigidity of the connecting part and the rigidity of the vibration transmission sheet are configured so that the two resonance peaks of the bone conduction speaker are less than 500 Hz.

3. 3. The bone conduction speaker according to claim 2, wherein the rigidity of the connecting part is greater than the rigidity of the vibration transmission sheet.

4. the stiffness of the connecting element is positively correlated with the elastic modulus and thickness of the connecting element and negatively correlated with the surface area of ​​the connecting element, or 3. The bone conduction speaker according to claim 2, wherein the stiffness of the vibration transmission sheet is positively correlated with the elastic modulus and thickness of the vibration transmission sheet, and negatively correlated with the surface area of ​​the vibration transmission sheet.

5. 3. The bone conduction speaker according to claim 2, wherein the connecting part is provided with a reinforcing material.

6. The bone conduction speaker according to claim 5, wherein the reinforcing material is a facade or a support rod.

7. The bone conduction speaker according to claim 2, characterized in that the connecting part is a hollow cylinder, one end face of the hollow cylinder is connected to one end face of the coil, and the other end face of the hollow cylinder is connected to at least one of the panel and the housing.

8. The bone conduction speaker of claim 2, characterized in that the connecting parts include a group of connecting rods, one end of each of which is connected to one end face of the coil and the other end of each of which is connected to at least one of the panel and the housing, and each of which is arranged circumferentially around the coil.

9. The driving force is located in a straight line, an area where the panel interacts with the user's body has a normal; The bone conduction speaker according to claim 1 , wherein the normal line is not parallel to the straight line.

10. the axis of the coil and the magnetic system are not parallel to the normal; 10. A bone conduction speaker according to claim 9, wherein the axis is perpendicular to at least one of the radial plane of the coil and the radial plane of the magnetic system.

11. The bone conduction speaker according to claim 1 , wherein the housing is connected to the panel via a connecting medium.

12. The bone conduction speaker according to claim 1 , wherein the housing and the panel are integrally formed.

13. The bone conduction speaker according to claim 1 , wherein the area of ​​the panel that contacts or abuts against the user's body is flat.

14. The area of ​​the panel is 20 mm ２ ~1000mm ２ 2. The bone conduction speaker according to claim 1, wherein the range is .

15. 15. The bone conduction speaker according to claim 1, wherein the side length of the panel is in the range of 5 mm to 40 mm.

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