Bone conduction speakers

Abstract

To provide a bone conduction speaker which can clearly reduce the sense of vibrations when a bone conduction speaker is at the peak of a low-frequency resonance and also can improve the sound quality of a bone conduction speaker.SOLUTION: A bone conduction speaker according to an embodiment includes: a vibration assembly having a vibration element and a vibration housing, the vibration element converting an electric signal into a mechanical vibration and the vibration housing contacting the face of a user and transmitting mechanical vibrations to the user by a bone conduction system to generate sound; and a resonance assembly having a first elastic element and a mass element connected to the vibration assembly by the first elastic element. The vibration assembly vibrates the resonance assembly, and the vibrations of the resonance assembly reduce the amplitude of the vibration housing.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] This application relates to the field of bone conduction speakers, and particularly to a bone conduction speaker that can improve the vibration feeling at low frequencies.

Background Art

[0002] A bone conduction speaker can convert an audio signal into a mechanical vibration signal so as to let the wearer hear the voice, and can transmit the mechanical vibration signal to the auditory nerve of the human body through human tissues and bones. After expanding the frequency response range of the bone conduction speaker, especially the low-frequency response range, the amplitude of the low-frequency resonance peak of the bone conduction speaker is large. Therefore, the vibration feeling generated by the bone conduction speaker is strong, which affects the user experience, and the large peak value of the resonance peak also degrades the sound quality.

Summary of the Invention

Problems to be Solved by the Invention

[0003] This application provides a bone conduction speaker that can not only significantly reduce the vibration feeling at the low-frequency resonance peak of the bone conduction speaker, but also improve the sound quality of the bone conduction speaker.

Means for Solving the Problems

[0004] An object of the present invention is to provide a bone conduction speaker that can reduce the amplitude at the low-frequency resonance peak of the bone conduction speaker, reduce the vibration feeling of the bone conduction speaker, and improve the sound quality.

[0005] In order to achieve the above object of the invention, the technical means according to the present invention are as follows.

[0006] A bone conduction speaker includes a vibration assembly that includes a vibrating element that converts electrical signals into mechanical vibrations, and a vibrating housing that contacts the user's face and transmits the mechanical vibrations to the user by bone conduction to generate sound, and a resonant assembly that includes a first elastic element and a mass element connected to the vibration assembly by the first elastic element, wherein the vibration assembly vibrates the resonant assembly, and the vibration of the resonant assembly reduces the amplitude of the vibration housing.

[0007] In some embodiments, the ratio of the mass of the mass element to the mass of the vibration housing is in the range of 0.04 to 1.25.

[0008] In some embodiments, the ratio of the mass of the mass element to the mass of the vibration housing is in the range of 0.1 to 0.6.

[0009] In some embodiments, the vibration assembly generates a first low-frequency resonance peak at a first frequency, and the resonance assembly generates a second low-frequency resonance peak at a second frequency, with the ratio of the second frequency to the first frequency being in the range of 0.5 to 2.

[0010] In some embodiments, the vibration assembly generates a first low-frequency resonance peak at a first frequency, and the resonance assembly generates a second low-frequency resonance peak at a second frequency, with the ratio of the second frequency to the first frequency being in the range of 0.9 to 1.1.

[0011] In some embodiments, both the first frequency and the second frequency are less than 500 Hz.

[0012] In some embodiments, within a frequency range smaller than the first frequency, the amplitude of the resonant assembly is greater than the amplitude of the vibrating housing.

[0013] In some embodiments, the vibration assembly further includes a second elastic element, the vibration housing houses the vibration element and the second elastic element, and the vibration element transmits the mechanical vibration to the vibration housing via the second elastic element.

[0014] In some embodiments, the second elastic element is a vibration transmission sheet fixedly connected to the vibration housing.

[0015] In some embodiments, the first elastic element is fixedly connected to the vibration housing, and the vibration housing transmits the mechanical vibration to the mass element via the first elastic element.

[0016] In some embodiments, the resonant assembly is housed within the vibration housing and connected to the inner wall of the vibration housing by the first elastic element.

[0017] In some embodiments, the first elastic element includes a vibrating membrane, and the mass element includes a composite structure in close contact with the surface of the vibrating membrane.

[0018] In some embodiments, the composite structure includes a cone paper, an aluminum sheet, or a copper sheet.

[0019] In some embodiments, the vibration housing is provided with at least one sound vent, and the sound generated by the vibration of the resonant assembly is transmitted to the outside through the at least one sound vent.

[0020] In some embodiments, the at least one sound vent is formed on the side of the vibrating housing that faces away from the user's face.

[0021] In some embodiments, the bone conduction speaker further includes a fixed assembly that maintains stable contact between the bone conduction speaker and the user and is fixedly connected to the vibration housing.

[0022] In some embodiments, the resonance assembly is located outside the vibration housing and is connected to the outer wall of the vibration housing by the first elastic element.

[0023] In some embodiments, the mass element is a groove member, at least a part of the vibration housing is accommodated in the groove member, the first elastic element connects the outer wall of the vibration housing and the inner wall of the groove member, and a sound emission passage is formed between the inner wall of the groove member and the outer wall of the vibration housing.

[0024] In some embodiments, the bone conduction speaker further includes a fixing assembly that maintains stable contact between the bone conduction speaker and the user's face and is fixedly connected to the resonance assembly.

[0025] The present application will be further described by exemplary embodiments, and these exemplary embodiments will be described in detail with reference to the drawings. These embodiments are not limiting, and in these embodiments, the same numbers indicate similar structures.

Brief Description of the Drawings

[0026] [Figure 1] It is a configuration block diagram of a bone conduction speaker according to some embodiments of the present application. [Figure 2] It is a schematic longitudinal sectional view of a bone conduction speaker without a resonance assembly according to some embodiments of the present application. [Figure 3] It is a part of the frequency response curve of a bone conduction speaker without a resonance assembly according to some embodiments of the present application. [Figure 4] It is a schematic longitudinal sectional view of a bone conduction speaker with a resonance assembly added according to some embodiments of the present application. [Figure 5] It is a part of the frequency response curve of a bone conduction speaker with a resonance assembly added according to some embodiments of the present application. [Figure 6] It is a schematic longitudinal sectional view of another bone conduction speaker according to some embodiments of the present application. [Figure 7] This is a schematic longitudinal cross-sectional view of yet another bone conduction speaker relating to some embodiments of the present application. [Figure 8] This is a schematic longitudinal cross-sectional view of yet another bone conduction speaker relating to some embodiments of the present application. [Figure 9] This is a schematic longitudinal cross-sectional view of yet another bone conduction speaker relating to some embodiments of the present application. [Figure 10] This is a schematic diagram of a simplified mechanical model of a bone conduction speaker without an additional resonant assembly, according to some embodiments of the present application. [Figure 11] This is a schematic diagram of a simplified mechanical model of a bone conduction speaker with an added resonant assembly, according to some embodiments of the present invention. [Modes for carrying out the invention]

[0027] To more clearly illustrate the technical means of the embodiments of this application, the drawings necessary for describing the embodiments are briefly described below. Clearly, the drawings described below are only examples or embodiments of this application, and those skilled in the art can apply this application to other similar scenarios based on these drawings without requiring any creative effort. It should be understood that these exemplary embodiments are merely intended to enable those skilled in the art to better understand and implement the invention, and do not limit the scope of the invention in any way. Unless otherwise stated or otherwise evident from the language context, the same reference numerals in the figures indicate the same structure or operation.

[0028] As used in this application and claims, unless the context explicitly indicates otherwise, terms such as “one,” “one,” “one type,” and / or “the” do not specifically refer to the singular form but may include the plural form. Generally, the terms “includes” and “contains” merely indicate the inclusion of clearly identified steps and elements, which are not an exclusive list, and the method or apparatus may also include other steps or elements. The term “based on” means “based at least in part.” The term “one embodiment” indicates “at least one embodiment.” The term “another embodiment” indicates “at least one other embodiment.” Relevant definitions of other terms are given in the following description. Hereafter, without loss of generality, when describing the bone conduction-related techniques in the present invention, we will use the terms “bone conduction speaker” or “bone conduction earphone.” This description is merely one form of bone conduction application, and those skilled in the art may replace “speaker” or “earphone” with other similar words such as “player” or “hearing aid.” In fact, various embodiments of the present invention can be easily applied to auditory devices other than speakers. For example, those skilled in the art, having understood the basic principle of bone conduction speakers, can make various modifications and changes to the form and details of the specific methods and steps for implementing bone conduction speakers without departing from this principle, and in particular, by adding ambient sound pickup and processing functions to the bone conduction speaker, the speaker can realize the function of a hearing aid. For example, an acoustic transmitter such as a microphone can pick up sounds from the environment surrounding the user / wearer and transmit the sound (or generated electrical signal) processed by a specific algorithm to the bone conduction speaker. That is, by modifying the bone conduction speaker to add an ambient sound pickup function and transmitting the sound to the user / wearer via the bone conduction speaker after specific signal processing, the function of a bone conduction hearing aid can be realized.For example, the algorithms mentioned herein may include one or a combination of the following: noise reduction, automatic gain control, acoustic feedback suppression, wide dynamic range compression, active environmental recognition, active noise cancellation, directional processing, tinnitus prevention processing, multi-channel wide dynamic range compression, active howling suppression, and volume control.

[0029] Figure 1 is a block diagram of the configuration of a bone conduction speaker according to some embodiments of the present invention. As shown in Figure 1, the bone conduction speaker 100 may include a vibration assembly 110, a resonance assembly 120, and a fixing assembly 130.

[0030] The vibration assembly 110 can generate mechanical vibrations. The generation of mechanical vibrations involves energy conversion, and the bone conduction speaker 100 can achieve the conversion of signals containing sound information into mechanical vibrations by the vibration assembly 110. The conversion process may involve the coexistence and conversion of multiple different types of energy. For example, an electrical signal can be directly converted into mechanical vibrations by the energy conversion device of the vibration assembly 110 to generate sound. Furthermore, for example, sound information may be contained in an optical signal, and a specific energy conversion device can realize the process of converting an optical signal into a vibration signal. Other types of energy that can coexist and be converted during the operation of the energy conversion device include thermal energy, magnetic field energy, etc. The energy conversion method of the energy conversion device may include moving coil type, electrostatic type, piezoelectric type, balanced armature type, pneumatic type, electromagnetic type, etc. In some embodiments, the vibration assembly 110 may include a vibration housing and a vibration element.

[0031] At least a portion of the vibration housing may be in contact with the face of a person to transmit mechanical vibrations to the facial bones of the person, so that the person can hear the sound. The vibration housing may be configured as a sealed or open enclosure, and the vibration element may be installed inside the vibration housing. In some embodiments, the vibration housing may not be configured as an enclosure and may be directly connected to the vibration element. In some embodiments, the vibration housing may be directly or indirectly connected to the vibration element to transmit mechanical vibrations of the vibration element to the auditory nerve via the bone, so that the person can hear the sound.

[0032] In some embodiments, the vibrating element (i.e., energy conversion device) may include a magnetic circuit assembly. The magnetic circuit assembly can provide a magnetic field. The magnetic field can convert a signal containing audio information into a mechanical vibration signal. In some embodiments, the audio information may include video files, audio files, or data or files that can be converted to audio in a specific way, having a specific data format. The signal containing audio information may come from the memory assembly of the bone conduction speaker 100 itself, or from an information generation, storage, or transmission system other than the bone conduction speaker 100. The signal containing audio information may include one or a combination of electrical signals, optical signals, magnetic signals, mechanical signals, etc. The signal containing audio information may come from one signal source or multiple signal sources. The multiple signal sources may or may not be related. In some embodiments, the bone conduction speaker 100 can acquire the signal containing audio information in several different ways, and the signal acquisition may be wired, wireless, real-time, or delayed. For example, the bone conduction speaker 100 may receive electrical signals containing audio information via a wired or wireless connection, or it may directly acquire data from a storage medium and generate an audio signal. Alternatively, for example, the bone conduction speaker 100 may include an assembly having an audio collection function that picks up sound in the environment, converts the mechanical vibrations of the sound into electrical signals, and processes them with an amplifier to obtain an electrical signal that satisfies specific requirements. In some embodiments, the wired connection may include a metal cable, an optical cable, or a combination thereof, such as one or more types of coaxial cables, communication cables, flexible cables, spiral cables, non-metallic sheathed cables, metal sheathed cables, multi-core cables, twisted-pair cables, ribbon cables, shielded cables, telecommunications cables, paired cables, two-core parallel wiring, twisted pairs, etc. The examples described above are merely for illustrative purposes, and the medium of the wired connection may be other types of mediums, such as other electrical signals or optical signals as transmission carriers.

[0033] Wireless connectivity may include wireless communication, free-space optical communication, voice communication, electromagnetic induction, etc. Wireless communication may include IEEE 802.11 standard, IEEE 802.15 standard (e.g., Bluetooth® technology and cellular technology), first-generation mobile communication technology, second-generation mobile communication technology (e.g., FDMA, TDMA, SDMA, CDMA, and SSMA), general-purpose packet radio service technology, third-generation mobile communication technology (e.g., CDMA2000, WCDMA®, TD-SCDMA, and WiMAX), fourth-generation mobile communication technology (e.g., TD-LTE and FDD-LTE), satellite communication (e.g., GPS technology), near-field communication (NFC), and other operating systems in other ISM bands (e.g., 2.4GHz). Free-space optical communication may include visible light signals, infrared signals, etc. Voice communication may include sound wave signals, ultrasonic signals, etc. Electromagnetic induction may include near-field communication technology, etc. The examples described above are merely for illustrative purposes, and the wireless connection medium may be of other types, such as Z-wave technology, or other paid radio frequency bands for civilian or military use. For example, in some application scenarios of this technology, the bone conduction speaker 100 may acquire signals containing audio information from other devices using Bluetooth® technology.

[0034] The resonant assembly 120 is connected to the vibration assembly 110, and when mechanical vibration occurs in the vibration assembly 110, at least some of the mechanical vibration is transmitted to the resonant assembly 120, causing the resonant assembly 120 to vibrate, thereby reducing the amplitude of the vibration assembly 110. In some embodiments, the resonant assembly 120 may include a first elastic element and a mass element connected to the vibration assembly 110 by the first elastic element. The vibration assembly 110 can transmit mechanical vibration to the mass element via the first elastic element, causing the mass element to vibrate.

[0035] The fixing assembly 130 maintains stable contact between the bone conduction speaker 100 and the user's face by providing fixed support to the vibration assembly 110 and the resonance assembly 120. The fixing assembly 130 may include one or more fixing connection members. One or more fixing connection members can connect the vibration assembly 110 and / or the resonance assembly 120. In some embodiments, the fixing assembly 130 can enable bilateral wear. For example, both ends of the fixing assembly 130 may be fixedly connected to two sets of vibration assemblies 110 (or resonance assemblies 120). When the user wears the bone conduction speaker 100, the fixing assembly 130 can fix the two sets of vibration assemblies 110 (or resonance assemblies 120) near the user's left ear and right ear, respectively. In some embodiments, the fixing assembly 130 can enable unilateral wear. For example, the fixing assembly 130 may be fixedly connected to only one set of vibration assemblies 110 (or resonance assemblies 120). When a user wears the bone conduction speaker 100, the fixing assembly 130 can secure the vibration assembly 110 (or resonance assembly 120) near one of the user's ears. In some embodiments, the fixing assembly 130 may be, but is not limited to, one or more combinations of glasses (e.g., sunglasses, augmented reality glasses, virtual reality glasses), helmets, and headbands.

[0036] The above description of the structure of the bone conduction speaker is merely a specific example and should not be considered the only feasible embodiment. Clearly, those skilled in the art, after understanding the basic principle of the bone conduction speaker, can make various modifications and changes to the specific methods, steps, and details of implementing the bone conduction speaker 100 without departing from this principle, and these modifications and changes are still within the scope described above. For example, the bone conduction speaker 100 may include one or more processors, which can execute one or more audio signal processing algorithms. The audio signal processing algorithms can correct or enhance the audio signal. For example, they may perform noise cancellation, acoustic feedback suppression, wide dynamic range compression, automatic gain control, active environmental recognition, active noise cancellation, directional processing, tinnitus prevention processing, multi-channel wide dynamic range compression, active howling suppression, volume control, or other similar processing on the audio signal, and these modifications and changes are still within the scope of the claims of the present invention. Also, for example, the bone conduction speaker 100 may include one or more sensors, such as a temperature sensor, a humidity sensor, a speed sensor, a displacement sensor, etc. The sensor can collect user information or environmental information.

[0037] Figure 2 is a schematic longitudinal cross-sectional view of a bone conduction speaker without an additional resonance assembly, according to some embodiments of the present application. As shown in Figure 2, in some embodiments, the bone conduction speaker 200 may include a vibration assembly 210 and a fixing assembly 230.

[0038] In some embodiments, the vibration assembly 210 may include a vibration element 211, a vibration housing 213, and a second elastic element 215 that elastically connects the vibration element 211 and the vibration housing 213. The vibration element 211 can generate mechanical vibration by converting an audio signal into a mechanical vibration signal. When mechanical vibration occurs in the vibration element 211, the second elastic element 215 can drive and vibrate the vibration housing 213. When the vibration element 211 transmits mechanical vibration to the vibration housing 213 via the second elastic element 215, the vibration frequency of the vibration housing 213 is the same as the vibration frequency of the vibration element 211.

[0039] The vibrating element 211 described herein may be an element that converts an audio signal into a mechanical vibration signal, such as a transducer. In some embodiments, the vibrating element 211 may include a magnetic circuit assembly and a coil, the magnetic circuit assembly being able to form a magnetic field, and the coil being able to generate mechanical vibrations in the magnetic field. Specifically, a signal current may be passed through the coil, which is located in the magnetic field formed by the magnetic circuit assembly and is driven to vibrate mechanically by an ampere force. At the same time, the magnetic circuit assembly receives a reaction force opposite to that of the coil. Due to the action of the ampere force, the vibrating element 211 can generate mechanical vibrations. The mechanical rotation of the vibrating element 211 may also be transmitted to the vibrating housing 213 so that the vibrating housing 213 vibrates in conjunction with the vibrating element 211.

[0040] In some embodiments, the vibration housing 213 may include a housing panel 2131, housing side plates 2132, and housing back plate 2133. The housing panel 2131 may be the surface of the vibration housing 213 that comes into contact with the user's face when the user wears the bone conduction speaker 200. The housing back plate 2133 is located on the surface opposite to the housing panel 2131. In some embodiments, the housing panel 2131 and the housing back plate 2133 are installed on both end faces of the housing side plates 2132, respectively. The housing panel 2131, housing side plates 2132, and housing back plate 2133 can form a shell-like structure with a certain housing space. In some embodiments, the vibration element 211 may be installed inside the shell-like structure.

[0041] In some embodiments, the housing panel 2131, housing side plate 2132, and housing back plate 2133 may be manufactured from the same material or different materials. For example, the housing panel 2131 and housing side plate 2132 may be manufactured from the same material, while the material used to manufacture the housing back plate 2133 may be different from the material used for the former two. In some embodiments, the housing panel 2131, housing side plate 2132, and housing back plate 2133 may each be manufactured from different materials.

[0042] In some embodiments, the materials used to manufacture the housing panel 2131 include acrylonitrile butadiene styrene (ABS), polystyrene (PS), high-impact polystyrene (HIPS), polypropylene (PP), polyethylene terephthalate (PET), polyester (PES), polycarbonate (PC), polyamides (PA), polyvinyl chloride (PVC), polyurethanes (PU), polyvinylidene chloride, polyethylene (PE), and polymethyl methacrylate (Polymethyl The materials include, but are not limited to, any material from among methacrylate (PMMA), polyether-ether-ketone (PEEK), phenolic formaldehyde resin (PF), urea-formaldehyde resin (UF), melamine formaldehyde resin (MF), and several metals, alloys (e.g., aluminum alloys, chromium-molybdenum steel, scandium alloys, magnesium alloys, titanium alloys, magnesium-lithium alloys, nickel alloys, etc.), glass fibers, or carbon fibers, or any combination of any of the above materials. In some embodiments, the material used to manufacture the housing panel 2131 is any combination of glass fibers and carbon fibers with materials such as polycarbonate (PC) and polyamides (PA). In some embodiments, the material used to manufacture the housing panel 2131 may be obtained by mixing carbon fibers and polycarbonate (PC) in a certain ratio.In some embodiments, the material used to manufacture the housing panel 2131 may be obtained by mixing carbon fiber, glass fiber, and polycarbonate (PC) in certain proportions. In some embodiments, the material used to manufacture the housing panel 2131 may be obtained by mixing glass fiber and polycarbonate (PC) in certain proportions, or by mixing glass fiber and polyamides (PA) in certain proportions.

[0043] In some embodiments, the housing panel 2131 needs to have a certain thickness to ensure its rigidity. In some embodiments, the thickness of the housing panel 2131 is 0.3 mm or more. Preferably, the thickness of the housing panel 2131 is 0.5 mm or more. More preferably, the thickness of the housing panel 2131 is 0.8 mm or more. More preferably, the thickness of the housing panel 2131 is 1 mm or more. As the thickness increases, the weight of the housing 700 also increases, which increases the weight of the bone conduction speaker 200 and affects the sensitivity of the bone conduction speaker 200. Therefore, the thickness of the housing panel 2131 should not be too large. In some embodiments, the thickness of the housing panel 2131 is 2.0 mm or less. Preferably, the thickness of the housing panel 2131 is 1.5 mm or less.

[0044] In some embodiments, the housing panel 2131 may be configured in a different shape. For example, the housing panel 2131 may be square, rectangular, approximately rectangular (for example, a structure in which the four corners of a rectangle are replaced with arcs), elliptical, circular, or any other arbitrary shape.

[0045] In some embodiments, the housing panel 2131 may be composed of the same type of material. In some embodiments, the housing panel 2131 may be composed of two or more types of materials laminated together. In some embodiments, the housing panel 2131 may be composed of a combination of one layer of material with a high Young's modulus and one layer of material with a low Young's modulus. This has the advantage of ensuring the rigidity requirements of the housing panel 2131, improving comfort when in contact with the human face, and improving the fit of the vibration panel 2131 when it comes into contact with the human face. In some examples, materials with a high Young's modulus include acrylonitrile butadiene styrene (ABS), polystyrene (PS), high-impact polystyrene (HIPS), polypropylene (PP), polyethylene terephthalate (PET), polyester (PES), polycarbonate (PC), polyamides (PA), polyvinyl chloride (PVC), polyurethanes (PU), polyvinylidene chloride, polyethylene (PE), and polymethyl methacrylate (Polymethyl The material may be any material from among methacrylate (PMMA), polyether-ether-ketone (PEEK), phenolic formaldehyde resin (PF), urea-formaldehyde resin (UF), melamine formaldehyde resin (MF), and several metals, alloys (e.g., aluminum alloy, chromium-molybdenum steel, scandium alloy, magnesium alloy, titanium alloy, magnesium-lithium alloy, nickel alloy, etc.), glass fiber, or carbon fiber, or any combination of any of the above materials.

[0046] In some embodiments, the portion of the housing panel 2131 that comes into contact with the skin of the human body may be the entire area or a portion of the area of ​​the housing panel 2131. For example, if the housing panel 2131 has an arc-shaped structure, only a portion of the area of ​​the arc-shaped structure may come into contact with the skin of the human body. In some embodiments, the housing panel 2131 may come into surface contact with the skin of the human body. In some embodiments, the surface of the housing panel 2131 that comes into contact with the human body may be flat. In some embodiments, the outer surface of the housing panel 2131 may have some protrusions or recesses. In some embodiments, the outer surface of the housing panel 2131 may be a curved surface with any contour.

[0047] The vibration element 211 includes a magnetic circuit assembly, and the vibration element 211 is housed within the vibration housing 213. Therefore, the larger the volume of the vibration housing 213 (i.e., the volume of the housing space), the larger the magnetic circuit assembly that can be housed inside the vibration housing 213, and thus the higher the sensitivity of the bone conduction speaker 200. The sensitivity of the bone conduction speaker 200 can be reflected by the volume generated in the bone conduction speaker 200 after a certain audio signal is input. When the same audio signal is input, the higher the volume generated in the bone conduction speaker 200, the higher the sensitivity of the bone conduction speaker 200. In some embodiments, the volume of the bone conduction speaker 200 increases with increasing volume of the housing space in the vibration housing 213. Therefore, in this application, there is a certain requirement for the volume of the vibration housing 213. In some embodiments, the volume of the vibration housing 213 may be 2000 mm3 to 6000 mm3 so that the bone conduction speaker 200 has high sensitivity (volume). Preferably, the volume of the vibration housing 213 may be 2000 mm³ to 5000 mm³. Preferably, the volume of the vibration housing 213 may be 2800 mm³ to 5000 mm³. Preferably, the volume of the vibration housing 213 may be 3500 mm³ to 5000 mm³. Preferably, the volume of the vibration housing 213 may be 1500 mm³ to 3500 mm³. Preferably, the volume of the vibration housing 213 may be 1500 mm³ to 2500 mm³.

[0048] The fixed assembly 230 is fixedly connected to the vibration housing 213 of the vibration assembly 210, and the fixed assembly 230 maintains stable contact between the bone conduction speaker 200 and human tissue or bone, prevents vibration of the bone conduction speaker 200, and ensures that the housing panel 2131 can stably transmit sound. In some embodiments, the fixed assembly 230 may be an arc-shaped elastic member that can generate a repulsive force in the middle of the arc so that it can stably contact the skull of the human body. Taking the ear hook as an example, based on Figure 2, the tip point p of the ear hook can be considered a fixed point because it makes good contact with the head of the human body. The ear hook is fixedly connected to the housing side plate 2132, and the ear hook is fixed to the housing side plate 2132 or housing back plate 2133 by a fixed connection method including adhesive bonding, locking, welding or screwing. The portion of the ear hook connected to the vibration housing 213 may be manufactured from the same material as the housing side plate 2132 or housing back plate 2133, a different material, or partially the same material. In some embodiments, the ear hook may further include plastic, silicone rubber, and / or metallic material so that the ear hook has low rigidity (i.e., a low spring constant). For example, the ear hook may include an arc-shaped titanium wire. Preferably, the ear hook may be integrally molded with the housing side plate 2132 or housing back plate 2133. For more examples of the vibration assembly 210 and vibration housing 213, one can refer to the PCT applications filed on January 5, 2019, no. PCT / CN2019 / 070545 and PCT / CN2019 / 070548, the entire contents of which are incorporated herein by reference.

[0049] As previously mentioned, the vibration assembly 210 further includes a second elastic element 215. The second elastic element 215 can elastically connect the vibration element 211 and the vibration housing 213 so that the mechanical vibrations of the vibration element 211 can be transmitted to the vibration housing 213 by the second elastic element 215. When mechanical vibrations are generated in the vibration housing 213, they come into contact with the wearer's (or user's) face and transmit the mechanical vibrations to the auditory nerve via the bone, thereby allowing the human body to hear the sound.

[0050] In some embodiments, the vibrating element 211 and the second elastic element 215 may be housed inside the vibration housing 213, and the second elastic element 215 may connect the vibrating element 211 to the inner wall of the vibration housing 213. In some embodiments, the second elastic element 215 may include a first portion and a second portion. The first portion of the second elastic element 215 may be connected to the vibrating element 211 (e.g., the magnetic circuit assembly of the vibrating element 211), and the second portion of the second elastic element 215 may be connected to the inner wall of the vibration housing 213.

[0051] In some embodiments, the second elastic element 215 may be a vibration transmission sheet. The first portion of the vibration transmission sheet may be connected to the vibration element 211, and the second portion of the vibration transmission sheet may be connected to the vibration housing 213. Specifically, the first portion of the vibration transmission sheet may be connected to the magnetic circuit assembly of the vibration element 211, and the second portion of the vibration transmission sheet may be connected to the inner wall of the vibration housing 213. Preferably, the vibration transmission sheet has an annular structure, and the first portion of the vibration transmission sheet is closer to the central region of the vibration transmission sheet than the second portion. For example, the first portion of the vibration transmission sheet may be located in the central region of the vibration transmission sheet, and the second portion may be located on the circumferential side of the vibration transmission sheet.

[0052] In some embodiments, the vibration transmission sheet may be an elastic member so as to be able to transmit the mechanical vibrations of the vibration element 211 to the vibration housing 213. The elasticity of the vibration transmission sheet may be determined by many factors such as the material, thickness, and structure of the vibration transmission sheet.

[0053] In some embodiments, the material used to manufacture the vibration transmission sheet includes, but is not limited to, plastics (e.g., polymer polyethylene, blown nylon, engineering plastics, etc.), steel (e.g., stainless steel, carbon steel, etc.), and lightweight alloys (e.g., aluminum alloys, beryllium copper, magnesium alloys, titanium alloys, etc.), but is not limited to, other single materials or composite materials capable of achieving similar performance. The composite material may include, but is not limited to, other organic and / or inorganic materials such as glass fibers, carbon fibers, boron fibers, graphite fibers, graphene fibers, silicon carbide fibers, or aramid fibers as reinforcing materials, or various glass fiber reinforced plastics composed of glass fiber reinforced unsaturated polyester, epoxy resin, or phenolic resin matrices.

[0054] In some embodiments, the vibration transmission sheet may have a certain thickness. In some embodiments, the thickness of the vibration transmission sheet is 0.005 mm or more. Preferably, in some embodiments, the thickness of the vibration transmission sheet is 0.005 mm to 3 mm. More preferably, the thickness of the vibration transmission sheet is 0.01 mm to 2 mm. More preferably, the thickness of the vibration transmission sheet is 0.01 mm to 1 mm. Even more preferably, the thickness of the vibration transmission sheet is 0.02 mm to 0.5 mm.

[0055] In some embodiments, the elasticity of the vibration transmission sheet may be provided by the structure of the vibration transmission sheet. For example, the vibration transmission sheet may be an elastic structure, and even if the rigidity of the material used to manufacture the vibration transmission sheet is high, the structure of the vibration transmission sheet can provide elasticity. In some embodiments, the structure of the vibration transmission sheet may include, but is not limited to, a spring-like structure, an annular structure, or a substantially annular structure. In some embodiments, the structure of the vibration transmission sheet may be configured in a sheet shape. In some embodiments, the structure of the vibration transmission sheet may be configured in a stripe shape. Regarding the specific structure of the vibration transmission sheet, different vibration transmission sheets can be formed by combining the materials, thicknesses, and structures described above. For example, a sheet-like vibration transmission sheet may have different thickness distributions, where the thickness of a first part of the vibration transmission sheet is greater than the thickness of a second part of the vibration transmission sheet. In some embodiments, the number of vibration transmission sheets may be one or multiple. For example, the number of vibration transmission sheets may be two, with the second portion of each of the two vibration transmission sheets connected to the inner walls of two opposing housing side plates 2132, and the first portion of each of the two vibration transmission sheets connected to the vibration element 211.

[0056] In some embodiments, the vibration transmission sheet may be directly connected to the vibration housing 213 and the vibration element 211. In some embodiments, the vibration transmission sheet may be connected to the vibration element 211 and the vibration housing 213 by adhesive. In some embodiments, the vibration transmission sheet may be further fixed to the vibration element 211 and the vibration housing 213 by welding, locking, riveting, screwing (e.g., connection by components such as screws, nuts, bolts, etc.), clamping, pinning, tapered keying, or integral molding. For more examples of vibration transmission sheets, one can refer to the PCT applications PCT / CN2019 / 070545 and PCT / CN2019 / 070548, filed on January 5, 2019, the entire contents of which are incorporated herein by reference.

[0057] In some embodiments, the vibration assembly 210 may further include a first connecting member. The vibration transmission sheet may be connected to the vibration element 211 by the first connecting member. In some embodiments, the first connecting member may be fixedly connected to the vibration element 211, as shown in Figure 2. For example, the first connecting member may be fixed to the surface of the vibration element 211. In some embodiments, a first portion of the vibration element 211 may be fixedly connected to the first connecting member. In some embodiments, the vibration transmission sheet may be further fixed to the first connecting member by welding, locking, riveting, screwing (e.g., connected by members such as screws, nuts, bolts), clamping, pinning, tapered keying, or integral molding. In some embodiments, the vibration assembly 210 may further include a second connecting member (not shown), the second connecting member may be fixed to the inner wall of the vibration housing 213, for example, the second connecting member may be fixed to the inner wall of the housing side plate 2132. The vibration transmission sheet may be connected to the vibration housing 213 by the second connecting member. In some embodiments, the second portion of the vibration element 211 may be fixedly connected to the second connecting member. The method of connecting the second connecting member to the vibration transmission sheet may be the same as or similar to the method of connecting the first connecting member to the vibration transmission sheet in the embodiments described above, and will not be described here.

[0058] Figure 3 shows a portion of the frequency response curves of bone conduction speakers without a resonant assembly, according to some embodiments of the present application. The horizontal axis represents frequency, and the vertical axis represents the vibration intensity (or amplitude) of the bone conduction speaker 200. Here, vibration intensity may be understood as the vibration acceleration of the bone conduction speaker 200. The larger the value on the vertical axis, the larger the amplitude of the bone conduction speaker 200, and the stronger the vibration sensation of the bone conduction speaker 200. For ease of explanation, in some embodiments, the audio frequency range below 500 Hz may be called the low-frequency region, the audio frequency range from 500 Hz to 4000 Hz may be called the intermediate-frequency region, and the audio frequency range above 4000 Hz may be called the high-frequency region. In some embodiments, the audio in the low-frequency region gives the user a distinct vibration sensation, and if a sharp peak appears in the low-frequency region (i.e., the vibration acceleration at a certain frequency is much higher than the vibration acceleration at other frequencies in that vicinity), the audio heard by the user is harsh and shrill, while the strong vibration sensation is also unpleasant. Therefore, it is desirable that sharp peaks and dips do not appear in the low-frequency range, and the flatter the frequency response curve, the higher the acoustic effect of the bone conduction speaker 200.

[0059] As shown in Figure 3, the bone conduction speaker 200 generates a low-frequency resonance peak in the low-frequency range (around 100 Hz). This low-frequency resonance peak may be generated by the combined action of the vibration assembly 210 and the fixing assembly 230. Because the vibration acceleration of this low-frequency resonance peak is large, the vibration sensation of the vibration panel 2131 is strong, and the user may experience facial pain when wearing the bone conduction speaker 200, affecting the user's comfort and experience during use.

[0060] Figure 4 is a schematic longitudinal cross-sectional view of a bone conduction speaker with an added resonant assembly, according to some embodiments of the present application. As shown in Figure 4, in some embodiments, the bone conduction speaker 400 includes a vibration assembly 410 and a resonant assembly 420. The resonant assembly 420 is elastically connected to the vibration assembly 410 and can transmit mechanical vibrations to the resonant assembly 420 when mechanical vibrations occur in the vibration assembly 410. The resonant assembly 420 can absorb the mechanical energy of the vibration assembly 410 when it is forced to vibrate, thereby achieving the objective of reducing the amplitude of the vibration assembly 410.

[0061] In some embodiments, the vibration assembly 410 may include a vibrating element 411, a vibrating housing 413, and a second elastic element 415. The vibrating housing 413 is elastically connected to the vibrating element 411 by the second elastic element 415. When mechanical vibration occurs in the vibrating element 411, the vibrating housing 413 can be driven to vibrate mechanically. In some embodiments, the vibrating element 411, the vibrating housing 413, and the second elastic element 415 are the same as or similar to the vibrating element 211, the vibrating housing 213, and the second elastic element 215 of the bone conduction speaker 200, respectively, and details of their structure are omitted here.

[0062] In some embodiments, the resonant assembly 420 may include a mass element 421 and a first elastic element 423, the first elastic element 423 being fixedly connected to the mass element 421. The mass element 421 may be connected to the vibration assembly 410 by the first elastic element 423. The vibration housing 413 transmits mechanical vibrations to the mass element 421 by the first elastic element 423, driving the mass element 421 to vibrate mechanically. When mechanical vibrations occur in the mass element 421, the vibration acceleration of the vibration housing 413, i.e., the vibration intensity, can be reduced, thereby reducing the perceived vibration of the vibration housing 413 and improving the user experience. In some embodiments, the first elastic element 423 may be connected to any other location on the vibration housing 413 other than the housing panel that directly contacts the user. For example, the first elastic element 423 may be connected to the housing side plate 4132 or the housing back plate 4133. In this situation, since the resonant assembly 420 does not come into direct contact with the skin of the human body, the vibration of the resonant assembly 420 does not cause an unpleasant vibration sensation to the user. In the example shown in Figure 4, the first elastic element 423 may be connected to the outside of the side of the vibration housing 413 facing the housing panel 4131.

[0063] Figure 5 shows a portion of the frequency response graph of a bone conduction speaker with a resonant assembly added, according to some embodiments of the present invention. Figure 5 further shows the frequency response curve of the resonant assembly. As can be seen from Figure 5, the frequency response curve of the bone conduction speaker 400 in the low-frequency range becomes flatter due to the influence of the resonant assembly 420, thereby avoiding the strong vibration sensation caused by sharp resonance peaks and improving the user experience.

[0064] For ease of understanding, if the bone conduction speaker does not include a resonant assembly, the mechanical model of the bone conduction speaker can be equivalent to the model shown in Figure 10. Specifically, the vibrating panel and vibrating element can be simplified to mass block m1 and mass block m2, respectively, the ear hook can be simplified to elastic connecting member k1, and the second elastic element can be simplified to elastic connecting member k2, with the damping of elastic connecting members k1 and k2 being R1 and R2, respectively. The vibrating panel and vibrating element vibrate under forces F and -F, respectively. The composite vibration system, consisting of the vibrating panel, vibrating element, vibration transmission sheet, and ear hook, is fixed at point p, the tip of the ear hook.

[0065] Similarly, for ease of understanding, if the bone conduction speaker includes a resonant assembly, the mechanical model of the bone conduction speaker can be equivalent to the model shown in Figure 11.

[0066] Specifically, m1 and m2 represent the masses of the vibration housing and vibration element, respectively; m3 represents the mass of the resonant assembly's mass element; k1 and R1 represent the elasticity and damping of the fixed assembly, respectively; k2 and R2 represent the elasticity and damping of the second elastic element, respectively; and k3 and R3 represent the elasticity and damping of the first elastic element. The entire composite vibration system is fixed to point p at the tip of the ear hook, and the vibration surface housing and vibration element vibrate under forces F and -F, respectively. After the addition of the resonant assembly, it is equivalent to increasing the stiffness and damping of the vibration housing, while the ampere force F and the reaction force -F of the ampere force remain unchanged. Since both the stiffness and damping of the vibration housing increase, the amplitude of the vibration housing can be reduced by adding the resonant assembly.

[0067] As can be understood, the vibration assembly 410 and the resonance assembly 420 can each generate one low-frequency resonance peak in the low-frequency region, and by utilizing the resonance assembly 420 to absorb the mechanical vibrations of the vibration housing 413, the objective of reducing the amplitude of the mechanical vibrations of the vibration housing 413 at that resonance peak can be achieved. Specifically, as shown in Figure 5, the curve "Without Resonance Assembly" shows the frequency response of the bone conduction speaker 400 when the resonance assembly 420 is not added, and it can be seen that the vibration assembly 410 (combined with the fixed assembly 230) can generate a first low-frequency resonance peak 450 at a first frequency f. The curve "With Resonance Assembly - Resonance Assembly" shows the frequency response of the resonance assembly 420 itself, and it can be seen that the resonance assembly 420 can generate a second low-frequency resonance peak 460 at a second frequency f0. The curve “With Resonant Assembly - Bone Conduction Speaker” shows the frequency response of the bone conduction speaker 400 generated by the interaction of the vibration assembly 410 and the resonant assembly 420. The frequency response in the low-frequency range of the bone conduction speaker 400 with the added resonant assembly 420 is flatter compared to the frequency response in the low-frequency range of the bone conduction speaker without the added resonant assembly 420 (e.g., bone conduction speaker 200 shown in Figure 2), and its amplitude near the first frequency f is clearly lower than that without the added resonant assembly 420. The first frequency f is the natural frequency of the vibration assembly 410 (combined with the fixed assembly 230), and the second frequency f0 is the natural frequency of the resonant assembly 420. In some embodiments, the natural frequencies are related to the material, mass, elastic modulus, and shape of the structure itself.

[0068] Furthermore, when the vibrating element 411 transmits mechanical vibration to the vibrating housing 413 via the second elastic element 415, the vibrating housing 413 is forced to vibrate, and the vibration frequency of the vibrating housing 413 is the same as the vibration frequency of the vibrating element 411. Similarly, when the vibrating housing 413 transmits mechanical vibration to the mass element 421 of the resonant assembly 420 via the first elastic element 423, the mass element 421 is forced to move, and the vibration frequency of the mass element 421 is the same as the vibration frequency of the vibrating housing 413. As can be seen from Figure 5, in the frequency response of the resonant assembly 420 itself, within the range from 100 Hz to the second frequency f0, the vibration acceleration of the resonant assembly 420 increases with increasing frequency. When the frequency is the second frequency f0, a second low-frequency resonance peak 460 appears. If the frequency continues to increase, the vibration acceleration of the resonant assembly 420 decreases with increasing frequency. As can be understood, the frequency response of the resonant assembly 420 can reflect the response of the resonant assembly 420 to external vibrations of different frequencies (i.e., vibrations of the vibrating housing 413). For example, at and around the second frequency f0, the resonant assembly 420 absorbs the most mechanical energy from the vibrating housing 413. In this way, the resonant assembly 420 mainly reduces vibrations near the low-frequency resonance peak of the vibrating housing 413, and has little to no effect on vibrations of the vibrating housing 413 that are not near the low-frequency resonance peak, thereby resulting in a flatter frequency response curve for the bone conduction speaker 400 and the advantage of higher sound quality.

[0069] In some embodiments, in order to reduce the vibration intensity at the first low-frequency resonance peak 450 of the vibration housing 413, the frequency f0 corresponding to the second resonance peak 460 of the resonance assembly 420 can be set near the frequency f corresponding to the first resonance peak 450 of the vibration housing 413. As shown in Figure 5, in some embodiments, the ratio of the second frequency f0 to the first frequency f is in the range of 0.5 to 2. Preferably, the ratio of the second frequency f0 to the first frequency f is in the range of 0.65 to 1.5. More preferably, the ratio of the second frequency f0 to the first frequency f is in the range of 0.75 to 1.25. Even more preferably, the ratio of the second frequency f0 to the first frequency f is in the range of 0.85 to 1.15. Even more preferably, the ratio of the second frequency f0 to the first frequency f is in the range of 0.9 to 1.1.

[0070] To broaden the frequency response range of the bone conduction speaker 400, the structure and materials of the vibration assembly 410 and the resonance assembly 420 can be modified to set their low-frequency resonance peaks at lower frequencies. In some embodiments, the first low-frequency resonance peak 450 and the second low-frequency resonance peak 460 may both appear in the low-frequency region. Preferably, the first frequency f and the second frequency f0 may both be less than 800 Hz. More preferably, the first frequency f and the second frequency f0 may both be less than 700 Hz. More preferably, the first frequency f and the second frequency f0 may both be less than 600 Hz. Even more preferably, the first frequency f and the second frequency f0 may both be less than 500 Hz.

[0071] In some embodiments, by optimizing the structure and materials of the resonant assembly 420 (for example, optimizing the mass of the mass element 421, the elastic modulus of the first elastic element 423, etc.), the resonant assembly 420 can vibrate significantly more than the vibration housing 413 after the vibration housing 413 transmits vibrations to the resonant assembly 420. For example, within at least some frequency ranges smaller (or larger) than the first frequency f, the amplitude of the resonant assembly 420 may be larger than the amplitude of the vibration housing 413. In this case, since the resonant assembly 420 does not directly contact the user, the large vibrations of the resonant assembly 420 do not cause an unpleasant vibration sensation to the user. Furthermore, because the amplitude of the resonant assembly 420 is large, the mass element 421 of the resonant assembly 420 can be designed with a large area structure, and as the resonant assembly 420 vibrates, the vibration of the large-area mass element 421 vibrates the air, generating low-frequency air-conducted sound, thereby improving the low-frequency response of the bone conduction speaker 400.

[0072] Furthermore, as can be seen from Figure 5, the interaction between the vibration housing 413 and the resonant assembly 420 allows the bone conduction speaker 400 to generate two low-frequency resonance peaks within the low-frequency range, which are the third low-frequency resonance peak 471 and the fourth low-frequency resonance peak 473, respectively. The vibrational accelerations of the third low-frequency resonance peak 471 and the fourth low-frequency resonance peak 473 are smaller than those of the first low-frequency resonance peak 450. This means that, compared to a bone conduction speaker without the resonant assembly 420 (e.g., the bone conduction speaker 200 shown in Figure 2), the bone conduction speaker 400 with the added resonant assembly 420 has smaller amplitudes of low-frequency resonance peaks, further improving the user experience when wearing the bone conduction speaker 400. In some embodiments, the bone conduction speaker may generate two low-frequency resonance peaks within a frequency range smaller than 450 Hz. Preferably, the bone conduction speaker 400 may generate two low-frequency resonance peaks within a frequency range smaller than 400 Hz. More preferably, the bone conduction speaker 400 may generate two low-frequency resonance peaks within a frequency range smaller than 350 Hz. Even more preferably, the bone conduction speaker 400 may generate two low-frequency resonance peaks within a frequency range smaller than 300 Hz. Even more preferably, the bone conduction speaker 400 may generate two low-frequency resonance peaks within a frequency range smaller than 200 Hz.

[0073] If the mass m3 of the mass element 421 of the resonant assembly 420 is very small, the influence of the resonant assembly 420 on the mechanical vibration of the vibration housing 413 will be small, and it will not be possible to effectively reduce the mechanical vibration of the vibration housing 413 near the first low-frequency resonance peak 450. For example, if the mass m3 of the mass element 421 of the resonant assembly 420 is too small, even if the resonant assembly 420 is added, the vibration acceleration of the first low-frequency resonance peak 450 of the vibration housing 413 will still be large, and it will not be possible to effectively reduce the vibration sensation of the bone conduction speaker 400. If the mass m3 of the mass element 421 of the resonant assembly 420 is very large, the influence of the resonant assembly 420 on the amplitude of the mechanical vibration of the bone conduction speaker 400 will be too large, and it will clearly change the frequency response of the bone conduction speaker 400. Therefore, it is necessary to control the mass m3 of the mass element 421 of the resonant assembly 420 within a certain range.

[0074] In some embodiments, the ratio of the mass m3 of the mass element 421 of the resonant assembly 420 to the mass m1 of the vibration housing 413 is in the range of 0.04 to 1.25. Preferably, the ratio of the mass m3 of the mass element 421 of the resonant assembly 420 to the mass m1 of the vibration housing 413 is in the range of 0.05 to 1.2. Preferably, the ratio of the mass m3 of the mass element 421 of the resonant assembly 420 to the mass m1 of the vibration housing 413 is in the range of 0.06 to 1.1. More preferably, the ratio of the mass m3 of the mass element 421 of the resonant assembly 420 to the mass m1 of the vibration housing 413 is in the range of 0.07 to 1.05. More preferably, the ratio of the mass m3 of the mass element 421 of the resonant assembly 420 to the mass m1 of the vibration housing 413 is in the range of 0.08 to 0.9. More preferably, the ratio of the mass m3 of the mass element 421 of the resonant assembly 420 to the mass m1 of the vibration housing 413 is in the range of 0.09 to 0.75. More preferably, the ratio of the mass m3 of the mass element 421 of the resonant assembly 420 to the mass m1 of the vibration housing 413 is in the range of 0.1 to 0.6.

[0075] Figure 6 is a schematic longitudinal cross-sectional view of another bone conduction speaker according to some embodiments of the present application. As shown in Figure 6, the bone conduction speaker 600 may include a vibration assembly 610 and a resonance assembly 620. The vibration assembly 610 can generate mechanical vibrations. The resonance assembly 620 can receive mechanical vibrations from the vibration assembly 610 and reduce the amplitude of the mechanical vibrations of the vibration assembly 610.

[0076] In some embodiments, the vibration assembly 620 may include a vibrating element 611, a vibrating housing 613, and a second elastic element 615. The vibrating element 611 may be elastically connected to the vibrating housing 613 by the second elastic element 615. When mechanical vibration occurs in the vibrating element 611, the vibrating housing 613 can be driven to vibrate mechanically, and the vibration can be transmitted to the tissues and bones of the user's face, and through the tissues and bones to the auditory nerve, thereby allowing the user to hear sound. In some embodiments, the vibrating element 611, the vibrating housing 613, and the second elastic element 615 are the same as or similar to the vibrating element 211, the vibrating housing 213, and the second elastic element 215 of the bone conduction speaker 200, respectively, and details of their structure are omitted here.

[0077] In some embodiments, the resonant assembly 620 may include a first elastic element 623 and a mass element 621. The mass element 621 may be elastically connected to the vibration housing 613 by the first elastic element 623. The vibration housing 613 reduces the amplitude of the vibration housing 613 because the vibration is partially absorbed by the mass element 621 by transmitting the vibration to the mass element 621 via the first elastic element 623.

[0078] As shown in Figure 6, the resonant assembly 620 may be housed within the vibration housing 613, and the resonant assembly 620 may be connected to the inner wall of the vibration housing 621 by the first elastic element 623.

[0079] In some embodiments, the first elastic element 623 may include a vibrating membrane. The circumferential side of the vibrating membrane may be connected to the interior of the housing side plate 6132 of the vibration housing 613 by a support structure, or directly connected. The housing side plate 6132 is a side wall installed to surround the housing panel 6131. ​​When vibration occurs in the vibration housing 613, the housing side plate 6132 can cause the vibrating membrane to vibrate. The vibrating membrane here may be called a passive vibrating membrane because it is connected to the vibration housing 613 and vibrates driven by the vibration housing 613. In some embodiments, the vibrating membrane may include, but is not limited to, a plastic vibrating membrane, a metal vibrating membrane, a paper vibrating membrane, a biological vibrating membrane, and the like.

[0080] In some embodiments, the mass element 621 may include a composite structure. This composite structure can be attached to the surface of the vibrating membrane to form a composite vibrating membrane (i.e., a resonant assembly 620). The composite structure attached to the surface of the vibrating membrane mainly performs the following functions: (1) The composite structure 621 can adjust the mass of the composite vibrating membrane so that the entire composite vibrating membrane is within a certain mass range, so that the passive vibrating membrane itself has a large amplitude, thereby effectively reducing the amplitude in the low-frequency range of the bone conduction speaker 600; and (2) The composite vibrating membrane structure formed by combining the composite structure 621 and the vibrating membrane has higher rigidity, making it less likely for higher-order modes to occur on the surface of the composite vibrating membrane and avoiding the appearance of many peaks in the frequency response of the passive vibrating membrane. The mass of the mass element 621 and the frequency response of the composite diaphragm formed by the mass element 621 and the diaphragm may be the same as or similar to the mass element (e.g., mass element 421) and resonant assembly (e.g., resonant assembly 420) in other embodiments of the present application, and such description is omitted here.

[0081] In some embodiments, the composite structure may include, but is not limited to, one of cone paper, aluminum sheet, or copper sheet, or a combination thereof. In some embodiments, the composite structure may be made of the same type of material. For example, the composite structure may be cone paper or aluminum sheet. In some embodiments, the composite structure may be made of different materials. For example, the composite structure may be a structure composed of a combination of cone paper and copper sheet. Alternatively, for example, the composite structure may be a structure composed of a mixture of aluminum and copper in a certain ratio.

[0082] In some embodiments, the connection method between the composite structure and the vibrating membrane may include, but is not limited to, adhesive bonding, welding, locking, riveting, screwing (screws, nuts, bolts, etc.), interlocking connections, clamp connections, pin connections, tapered key connections, and molded connections.

[0083] As can be understood, when the diaphragm vibrates, it can vibrate the air inside the vibrating housing 613, thereby generating sound. Therefore, in some embodiments, at least one sound-emitting hole 640 may be formed in the vibrating housing 613 to release the sound generated by the vibration of the diaphragm to the outside of the vibrating housing 613, and at least a portion of the released sound is perceived by the human ear. This portion of the sound can improve the bone conduction speaker 600's response in the low-frequency range so that the bone conduction speaker 600 can still maintain a constant volume even when the vibration sensation at low frequencies is reduced.

[0084] In some embodiments, at least one sound vent 640 may be formed at any location on the vibrating housing 613. In some embodiments, at least one sound vent 640 may be formed on the side of the vibrating housing 613 that faces away from the user's face, i.e., on the housing back plate 6133. In some embodiments, at least one sound vent 640 may be formed on the housing side plate 6132, for example, on the housing side plate 6132 facing the user's ear canal. In some other embodiments, at least one sound vent 640 may be further formed at a corner of the vibrating housing 613, for example, at the connection point between the housing side plate 6132 and the housing back plate 6133. In some embodiments, there may be multiple sound vents 640. Multiple sound vents 640 may be formed at different locations. For example, some of the multiple sound vents 640 may be formed on the housing back plate 6133, and others on the housing side plate 6132. In some embodiments, sound emitted from at least one sound vent 640 is conducted to the user's ear, thereby improving the low-frequency response of the bone conduction speaker 600. In some embodiments, the above objective can be achieved by positioning at least one sound vent 640 facing the user's ear. For example, when a user wears the bone conduction speaker 600, the housing side plate 6132 faces the person's ear, so at least one sound vent 640 can be placed on the housing side plate 6132 to emit sound from the sound vent 640 and conduct at least a portion of it to the person's ear. In some embodiments, the above objective can be achieved by providing an additional sound conduction structure. For example, a sound conduit can be installed at the exit of at least one sound vent 640, and sound can be conducted towards the person's ear by the sound conduit.

[0085] In some embodiments, the cross-sectional shape of the sound vent 640 may include, but is not limited to, a circular, square, triangular, polygonal, or the like.

[0086] In some embodiments, the bone conduction speaker 600 may include a fixed assembly 630, which may be fixedly connected to the vibration housing 613. The fixed assembly 630 can maintain stable contact between the bone conduction speaker 600 and the user's (e.g., wearer's) face, prevent shaking of the bone conduction speaker 600, and ensure stable sound transmission from the bone conduction speaker 600.

[0087] In some embodiments, the lower the stiffness of the fixed assembly 630 (i.e., the lower the spring constant), the more pronounced the low-frequency response at the first resonance peak 450 of the bone conduction speaker 600 (i.e., the greater the vibration acceleration and the higher the sensitivity), which helps improve the sound quality of the bone conduction speaker 600. On the other hand, when the stiffness of the fixed assembly 630 is low (i.e., the spring constant is low), it helps the vibration housing 613.

[0088] In some embodiments, the fixed assembly 630 may be directly and fixedly connected to the vibration housing 613. In some embodiments, the fixed assembly 630 and the vibration housing 613 may be connected by a connecting member. In some embodiments, the fixed assembly 630 may include a fixed connecting member. The fixed connecting member can connect the fixed assembly 630 and the vibration housing 613. In some embodiments, the fixed connecting member may be one or more of the following: silicone rubber, sponge, plastic, spring, and carbon sheet.

[0089] In some embodiments, the fixing assembly 630 may be in the form of an ear hook. One vibration housing 613 is connected to each end of the fixing assembly 630, fixing the two vibration housings 613 to the sides of the human skull in an ear hook manner. In some embodiments, the fixing assembly 630 may be a single ear clip. The fixing assembly 630 is individually connected to one vibration housing 613, and the vibration housing 613 can be fixed to one side of the human skull. The structure of the fixing assembly 630 may be the same as or similar to the fixing assembly in other embodiments of the present application (e.g., fixing assembly 230), which will not be described here.

[0090] Figure 7 is a schematic longitudinal cross-sectional view of another bone conduction speaker according to some embodiments of the present application. As shown in Figure 7, the bone conduction speaker 700 may include a vibration assembly 710 and a resonance assembly 720. The vibration assembly 710 may include a vibration element 711, a vibration housing 713, and a second elastic element 715. The second elastic element 715 elastically connects the vibration element 711 and the vibration housing 713 and transmits the mechanical vibration of the vibration element 711 to the vibration housing 713. In some embodiments, the vibration element 711, vibration housing 713, and second elastic element 715 are the same as or similar to the vibration element 211, vibration housing 213, and second elastic element 215 of the bone conduction speaker 200, respectively, and details of their structures are omitted here.

[0091] The resonant assembly 720 may include a mass element 721 and a first elastic element 723. The mass element 721 may be elastically connected to the vibration housing 713 by the first elastic element 723. As shown in Figure 7, the resonant assembly 720 may be installed outside the vibration housing 713. The resonant assembly 720 may be connected to the outer wall of the vibration housing 713 by the first elastic element 723. When mechanical vibration occurs in the vibration housing 713, the resonant assembly 720 can reduce the amplitude of the vibration housing 713 by absorbing some of the mechanical energy of the vibration housing 713.

[0092] In some embodiments, the mass element 721 may be configured in a different shape. For example, it may be a cube, a roughly cuboid (for example, a cube with eight arc-shaped corners), or an ellipsoid.

[0093] In some embodiments, the mass element 721 may be a grooved member. The vibration housing 713 may be at least partially housed in the grooved member. In some embodiments, the groove cross-sectional shape of the grooved member may be circular, square, polygonal, or the like. In some embodiments, the groove cross-sectional shape of the grooved member may match the external contour of the vibration housing 713. For example, if the external contour of the vibration housing 713 is a rectangular parallelepiped, the groove cross-sectional shape of the grooved member may be a corresponding square. In some embodiments, the vibration housing 713 may be completely housed in the groove of the grooved member. In some embodiments, the vibration housing 713 may be partially housed in the groove of the grooved member. For example, the housing panel 7131 and at least some of the housing side plates 7132 of the vibration housing 713 may be located outside the groove so that the housing panel 7131 can easily contact the skull of a human body and transmit vibrations. In some embodiments, the first elastic element 723 may connect the housing back plate 7133 and the inner wall of the grooved member. For example, a first portion of the first elastic element 723 is connected to the housing back plate 7133, and a second portion of the first elastic element 723 is connected to the inner wall of the groove member. Assuming the first elastic element 723 has an annular structure, the first portion of the first elastic element 723 may be located in the central region of the annular structure, and the second portion may be located on the circumferential side of the annular structure. In some embodiments, the first portion of the first elastic element 723 may be connected to the housing back plate 7133, and the second portion of the first elastic element 723 may be connected to the bottom plate of the groove member. In some embodiments, the first portion of the first elastic element 723 may be connected to the housing side plate 7132, and the second portion of the first elastic element 723 may be connected to the side plate of the groove member. In some embodiments, the vibration housing may not include the housing back plate 7133, and may include only the housing panel 7121 and the housing side plate 7132. In such cases, the resonant assembly 720 may be connected to the inner wall of the housing side plate 7132 or the vibration housing 713 by the first elastic element 723.

[0094] In some embodiments, the first elastic element 723 may be directly connected to the housing back plate 7133 and the groove member. In some embodiments, the first elastic element 723 may be connected to the housing back plate 7133 and the groove member by a connecting member. For example, a third connecting member may be fixedly installed on the housing back plate 7133, and a first portion of the first elastic element 723 may be fixedly connected to the third connecting member. A fourth connecting member may be fixedly installed on the groove member, and a second portion of the first elastic element 723 may be fixedly connected to the fourth connecting member. In some embodiments, the mass of the mass element 721 and the frequency response of the resonant assembly 720 formed by the mass element 721 and the first elastic element 723 may be the same as or similar to the mass element (e.g., mass element 421) and resonant assembly (e.g., resonant assembly 420) in other embodiments of the present application, which are not described here.

[0095] In some embodiments, the internal size of the groove member may be larger than the external size of the vibration housing 713, in which case a cavity can be formed between the vibration housing 713 and the groove member. The vibration housing 713 and the groove member can vibrate the air inside the cavity during vibration, thereby generating sound. In addition, a sound-releasing passage 740 may be formed between the groove member and the outer wall of the vibration housing 713. For example, in the embodiment shown in Figure 7, a gap exists between the side wall of the groove member and the housing side plate 7132, and this gap can be used as a sound-releasing passage 740. The sound generated by the air vibration between the vibration housing 713 and the groove member can be transmitted to the outside through the sound-releasing passage 740, and the human ear can receive a portion of the sound, achieving the effect of increasing the low frequencies and thus the volume to some extent.

[0096] In some embodiments, the bone conduction speaker 700 may further include a fixed assembly 730. The fixed assembly 730 can maintain contact between the bone conduction speaker 700 and the skull of the user's face. In some embodiments, the fixed assembly 730 may be fixedly connected to the resonant assembly 720. For example, the fixed assembly 730 may be fixedly connected to or integrally molded with a mass element 721 (e.g., a grooved member). In some embodiments, the fixed assembly 730 may be directly fixedly connected to the grooved member. In some embodiments, the fixed assembly 730 may be connected to the grooved member by a fixed connecting member.

[0097] In some embodiments, the fixing assembly 730 may be in the form of an ear hook. A grooved member and a vibration housing 713 housed in the grooved member are connected to each end of the fixing assembly 730, and the two grooved members are fixed to each side of the skull in an ear hook manner. In some embodiments, the fixing assembly 730 may be a single ear clip. The fixing assembly 730 is individually connected to one grooved member and a vibration housing 713 housed in the grooved member, and the grooved member can be fixed to one side of the skull of the human body. The structure of the fixing assembly 730 may be the same as or similar to the fixing assembly in other embodiments of the present application (e.g., fixing assembly 230), which will not be described here.

[0098] Figures 8 and 9 are schematic longitudinal cross-sectional views of another bone conduction speaker according to some embodiments of the present application. As shown in Figures 8 and 9, the bone conduction speaker 800 may include a vibration assembly 810 and a resonance assembly 820. The vibration assembly 810 may include a vibration element 811, a vibration housing 813 and a second elastic element 815 (shown in Figure 9). The second elastic element 815 elastically connects the vibration element 811 and the vibration housing 813.

[0099] The vibration housing 813 may be an individual plate-shaped or substantially plate-shaped structure. Compared to the embodiment shown in Figure 7, the vibration housing 813 differs in that it does not have a defined housing space, and the vibration element and the second elastic element 815 are connected to the vibration housing 813. The mass element 821 may be a grooved member, and the mass element 821 can define a housing space, and the vibration assembly 810 may be housed in the space formed by the mass element 821, at least in part. The first elastic element 823 can connect the mass element 821 and the vibration housing 813.

[0100] The vibrating element 811 may include a magnetic circuit assembly. A coil is installed in the vibrating housing 813, the magnetic circuit assembly is arranged around the outside of the coil, and a second elastic element 815 connects the magnetic circuit assembly and the vibrating housing 813.

[0101] The second elastic element 815 may be a vibration transmission sheet. In some embodiments, the vibration transmission sheet may have an annular structure. As shown in Figure 9, the annular vibration transmission sheet is positioned around the outside of the vibration housing 813, with the circumferential side of the annular vibration transmission sheet connected to the magnetic circuit assembly and the middle part of the annular vibration transmission sheet connected to the vibration housing 813. When mechanical vibration occurs due to an ampere force, the vibration housing 813 can transmit the vibration to the mass element 821 via the first elastic element 823, causing the mass element 821 to vibrate, and ultimately achieving the effect of reducing the amplitude of the vibration assembly 810.

[0102] In some embodiments, the vibrating element 811, the vibrating housing 813, and the second elastic element 815 are the same as or similar to the vibrating element 211, the vibrating housing 213, and the second elastic element 215 of the bone conduction speaker 200, respectively, and details of their structures are omitted here.

[0103] While the basic concepts have been explained above, it will be clear to those skilled in the art that the disclosure of the invention described above is merely presented as an example and does not limit the present application. Although not explicitly stated herein, those skilled in the art can make various changes, improvements, and modifications to the present application. These changes, improvements, and modifications are intended to be suggested by the present application and fall within the spirit and scope of the exemplary embodiments of the present application.

[0104] Furthermore, certain terms are used in this Application to describe embodiments thereof. For example, “one embodiment,” “one embodiment,” and / or “several embodiments” mean certain features, structures, or properties relating to at least one embodiment of this Application. Therefore, it should be emphasized and understood that two or more references to “one embodiment,” “one embodiment,” or “one alternative embodiment” in various parts of this Specification do not necessarily all refer to the same embodiment. Also, certain features, structures, or properties in one or more embodiments of this Application may be appropriately combined.

[0105] Furthermore, as will be understood by those skilled in the art, each aspect of this Application may be illustrated and described in several patentable classes or contexts, including any novel and useful combination of processes, machines, products or materials, or any novel and useful improvement thereto. Thus, each aspect of this Application may be executed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. Any of the above hardware or software may be referred to as “data blocks,” “modules,” “engines,” “units,” “assemblies,” or “systems.” Furthermore, each aspect of this Application may take the form of a computer program product embodied in one or more computer-readable media containing computer-readable program code.

[0106] Furthermore, unless explicitly stated in the claims, the enumerated order, use of alphanumeric characters, or use of other names of the processing elements or sequences described herein does not limit the order of the procedures and methods of this application. While the above disclosure illustrates various examples that are currently considered useful embodiments of the invention, such details are for illustrative purposes only, and it should be understood that the attached claims are not limited to the disclosed embodiments, but rather are intended to cover all modifications and equivalent combinations that fall within the spirit and scope of the embodiments of this application. For example, the system assembly described above may be implemented by hardware devices, but may also be implemented by a software-only solution, such as by installing the described system on an existing server or mobile device.

[0107] Similarly, in the foregoing description of embodiments of the present application, it should be understood that, for the purpose of simplifying the application and aiding in the understanding of embodiments of one or more inventions, various features may be grouped together in a single embodiment, drawing, or description. However, such disclosure methods should not be interpreted as reflecting an intention that the claimed subject matter requires more features than are enumerated in each claim. In fact, the features of an embodiment may be fewer than all the features of a single embodiment disclosed above.

[0108] In some embodiments, numbers are used to describe the number of components and attributes, and it should be understood that these numbers describing such embodiments are modified in some cases by the modifiers “about,” “approximately,” or “generally.” Unless otherwise specified, “about,” “approximately,” or “generally” indicates that the above numbers are allowed to vary by ±20%. Therefore, in some embodiments, the numerical parameters used in the specification and claims are all approximations that may vary depending on the characteristics required for the individual embodiment. In some embodiments, the numerical data should be rounded using standard rounding techniques, taking into account the specified number of significant figures. In some embodiments of this application, the numerical ranges and data used to determine the range are approximations, but in specific embodiments, such numbers are set as precisely as possible.

[0109] Finally, it should be understood that the embodiments relating to this application are merely illustrative of the principles of the embodiments thereof. Other modifications may also be within the scope of this application. Therefore, without limitation, alternative configurations of the embodiments thereof may be considered consistent with the teachings herein, for example. Thus, the embodiments of this application are not limited to those explicitly introduced and described herein. [Explanation of Symbols]

[0110] 100 Bone Conduction Speakers 110 Vibration Assembly 120 Resonant Assembly 130 Fixed Assembly 200 Bone Conduction Speakers 210 Vibration Assembly 230 Fixed Assembly 211 Vibration element 213 Vibration Housing 215 Second elastic element 400 Bone Conduction Speakers 410 Vibration Assembly 411 Vibration element 413 Vibration Housing 415 Second elastic element 421 Mass element 423 First elastic element

Claims

1. A vibration assembly comprising a vibration element that converts electrical signals into mechanical vibrations, and a vibration housing that contacts the user's face and transmits the mechanical vibrations to the user via bone conduction to generate sound, wherein the vibration housing includes a housing panel, a housing side plate, and a housing back plate, the housing panel is configured to contact the user's face, the housing back plate is positioned opposite the housing panel, and the housing panel and the housing back plate are positioned on both end faces of the housing side plate, respectively, A resonant assembly including a first elastic element and a mass element connected to the vibration assembly by the first elastic element, Includes, The first elastic element is fixedly connected to the vibration housing, and the vibration housing transmits the mechanical vibration to the mass element via the first elastic element. The resonance assembly is located outside the vibration housing. The resonant assembly is connected to the outer wall of the vibration housing by the first elastic element, A bone conduction speaker wherein the vibration assembly vibrates the resonance assembly, and the vibration of the resonance assembly reduces the amplitude of the vibration housing.

2. The bone conduction speaker according to claim 1, wherein the ratio of the mass of the mass element to the mass of the vibration housing is in the range of 0.04 to 1.

25.

3. The bone conduction speaker according to claim 1 or 2, wherein the vibration assembly generates a first low-frequency resonance peak at a first frequency, the resonance assembly generates a second low-frequency resonance peak at a second frequency, and the ratio of the second frequency to the first frequency is in the range of 0.5 to 2.

4. The bone conduction speaker according to claim 3, wherein the ratio of the second frequency to the first frequency is in the range of 0.9 to 1.

1.

5. The bone conduction speaker according to claim 4, wherein both the first frequency and the second frequency are less than 500 Hz.

6. The bone conduction speaker according to claim 5, wherein the amplitude of the resonant assembly is greater than the amplitude of the vibrating housing in a frequency range smaller than the first frequency.

7. The bone conduction speaker according to claim 3, wherein the vibration assembly further includes a second elastic element, the vibration housing houses the vibration element and the second elastic element, and the vibration element transmits the mechanical vibration to the vibration housing via the second elastic element.

8. The bone conduction speaker according to claim 1, wherein the mass element is a grooved member, and the vibration housing is housed in at least a portion of the grooved member.

9. The bone conduction speaker according to claim 8, wherein the first elastic element connects the outer wall of the vibration housing and the inner wall of the groove member, and a sound-emitting passage is formed between the inner wall of the groove member and the outer wall of the vibration housing.

10. Further equipped with a fixed assembly, The bone conduction speaker according to claim 1, wherein the fixing assembly is configured to maintain stable contact between the bone conduction speaker and the user, and the fixing assembly is fixedly connected to the vibration housing.

Images