Dual-vibration bone conduction speaker

Abstract

The present application proposes a dual-vibration plate bone conduction speaker, whose vibration component adopts a dual-vibration plate structure, including a first vibrating plate and a second vibrating plate arranged at intervals. The lower surface of the second vibrating plate is provided with a lower contact fulcrum for contacting the first vibrating plate, and the upper surface is provided with an upper contact fulcrum for contacting the human body. The vibration component of this structure has different vibration modes at low frequencies and high frequencies. It can extend the frequency range to high frequencies without losing power capacity, greatly expand the frequency response range, and make the frequency response characteristics smoother, thereby greatly improving the performance of the speaker.

Description

Technical Field

[0001] The present application relates to the field of acoustic technology, and in particular to a double-vibrating-plate bone-conduction loudspeaker. Background Art

[0002] Bone conduction is a method of sound transmission that converts sound into mechanical vibrations of varying frequencies, transmitting these waves through the skull, bony labyrinth, inner ear lymph, choroid plexus, and auditory center. Bone conduction headphones operate by bypassing the external auditory canal and eardrum to transmit sound signals directly to the ossicles. This means they don't need to be inserted into the ear, keeping the external auditory canal clean and ventilated, reducing strain on the ears and making them more comfortable to wear, thus enhancing the wearing experience. Furthermore, while most ambient noise is airborne, bone conduction headphones only receive sound signals that are directly transmitted through the skull. This reduces the potential for airborne noise, effectively improving sound quality. However, bone conduction headphones are open to the outer ear. While using the headphones, the outer ear automatically receives some ambient noise, which can affect the noise-canceling performance of the headphones.

[0003] Compared with the classic sound conduction method that generates sound waves through the diaphragm, bone conduction eliminates many steps in the transmission of sound waves, can achieve clear sound restoration in noisy environments, and the sound waves will not affect others due to diffusion in the air. Summary of the Invention

[0004] The main technical problem solved by this application is to provide a double-vibration plate bone conduction speaker with a larger frequency response range.

[0005] The present application proposes a dual-vibration plate bone conduction speaker, comprising: a housing; a transducer assembly, arranged in the housing, for generating vibrations under the excitation of an electrical signal; a vibration assembly, arranged in the housing, for transmitting the vibrations generated by the transducer assembly to a human body in contact; wherein the vibration assembly comprises: a first vibrating plate, connected to the transducer assembly; a second vibrating plate, spaced apart from the first vibrating plate; a lower contact fulcrum, arranged on the lower surface of the second vibrating plate and in contact with the first vibrating plate, for transmitting the vibrations of the first vibrating plate to the second vibrating plate; and an upper contact fulcrum, arranged on the upper surface of the second vibrating plate, for transmitting the vibrations of the second vibrating plate to the human body in contact.

[0006] In some optional embodiments, the compliance of the first vibration plate is smaller than the compliance of the second vibration plate.

[0007] In some optional embodiments, at low frequencies, the force impedance of the vibration component is greater than the force impedance of the first vibration plate; at high frequencies, the force impedance of the vibration component is less than the force impedance of the first vibration plate.

[0008] In some optional embodiments, the transducer assembly includes a magnet and a voice coil, the magnet is bonded to the first vibration plate, and the voice coil surrounds the magnet.

[0009] In some optional embodiments, the voice coil includes a first voice coil and a second voice coil, and the first voice coil is coaxially sleeved outside the second voice coil.

[0010] In some optional embodiments, the voice coil includes a first voice coil and a second voice coil, the first voice coil and the second voice coil are coaxially arranged, and the first voice coil and the second voice coil are spaced apart in the axial direction.

[0011] In some optional embodiments, the voice coil includes a first voice coil and a second voice coil, and the first voice coil and the second voice coil are connected in parallel.

[0012] In some optional embodiments, the voice coil includes a first voice coil and a second voice coil, and the first voice coil and the second voice coil are connected in series.

[0013] In some optional embodiments, the voice coil further includes a shunt capacitor, and the first voice coil is connected in parallel with the shunt capacitor and then in series with the second voice coil.

[0014] In some optional embodiments, the dual-vibration plate bone conduction speaker further includes: an inner pipe cavity, which is arranged in the outer shell, and the transducer component and the vibration component are arranged in the inner pipe cavity.

[0015] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0016] The dual-vibration plate bone conduction speaker of the present application has a dual-vibration plate structure in its vibration component, including a first vibrating plate and a second vibrating plate arranged at intervals. The lower surface of the second vibrating plate is provided with a lower contact fulcrum for contacting the first vibrating plate, and the upper surface is provided with an upper contact fulcrum for contacting the human body. The vibration component of this structure has different vibration modes at low frequencies and high frequencies, thereby extending the frequency range to high frequencies without losing power capacity, greatly expanding the frequency response range, and making the frequency response characteristics smoother, thereby greatly improving the performance of the speaker. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments and the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application and are not used to limit the present application.

[0018] Figure 1 is a cross-sectional view of a dual-vibration plate bone conduction speaker provided in an embodiment of the present application;

[0019] Figure 2 This is a circuit diagram of a dual-vibration plate bone conduction speaker provided in an embodiment of the present application. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0021] The terms "first," "second," "third," etc. in the specification, claims, and drawings of this application are used to distinguish different objects rather than to describe a specific order. In addition, the terms "include," "include," "have," and any variations thereof are intended to cover non-exclusive inclusions.

[0022] The following describes the embodiments in detail.

[0023] Please refer to Figure 1 , an embodiment of the present application provides a dual-vibration plate bone conduction loudspeaker (referred to as loudspeaker).

[0024] Among them, bone conduction is the abbreviation of bone conduction. Figure 1 As shown, the dual-vibration plate bone conduction speaker of this embodiment includes:

[0025] Shell 1, made of metal;

[0026] The transducer assembly is disposed in the housing 1 and is used to generate vibration under the stimulation of the electrical signal;

[0027] The vibration component is disposed in the housing 1 and is used to transmit the vibration generated by the transducer component to the human body in contact.

[0028] The vibration component may include:

[0029] A first vibrating plate 2 connected to the transducer assembly;

[0030] A second vibration plate 3 is spaced apart from the first vibration plate 2;

[0031] The lower contact support 4 is provided on the lower surface of the second vibration plate 3 and contacts the upper surface of the first vibration plate 2, and is used to transmit the vibration of the first vibration plate 2 to the second vibration plate 3;

[0032] The upper contact support 5 is provided on the upper surface of the second vibration plate 3 and is used to transmit the vibration of the second vibration plate 3 to the human body it contacts.

[0033] The transducer assembly may include:

[0034] The magnet 6 is bonded to the first vibrating plate 2, specifically, bonded to the lower surface of the first vibrating plate 2;

[0035] a voice coil 7, arranged around the magnet 6;

[0036] The circuit board 8 is used to carry the voice coil 7 and is electrically connected to the voice coil 7 .

[0037] Furthermore, an inner pipe cavity 9 may be provided in the housing 1 , and the transducer component and the vibration component are provided in the inner pipe cavity 9 , and the inner pipe cavity 9 plays an insulating and isolating role.

[0038] Common loudspeakers (receivers) are mostly dynamic-coil loudspeakers, which produce sound by utilizing the Ampere force on a current-carrying coil (voice coil) in a magnetic field, which drives a vibrating cone (paper cone) to vibrate and produce sound. The loudspeaker of the present application adopts a dynamic-magnet structure. When a signal current is passed through the voice coil 7, it interacts with the magnet 6, causing the magnet 6 to move. The magnet 6 adheres to the lower surface of the first vibrating plate 2, driving the first vibrating plate 2 to move together (the first vibrating plate 2 also controls and affects the movement of the magnet 6). The upper surface of the first vibrating plate 2 contacts the lower contact support 4 provided on the second vibrating plate 3, causing it to move, thereby driving the second vibrating plate 3 to move, and then driving the upper contact support 5 provided on the second vibrating plate 3 to move. The upper contact support 5 is in contact with the human body. Thus, the vibration of the input electrical signal before it is converted into a sound wave (vibration signal) can be used as electromagnetic excitation to directly transmit it through the human body's bones to the auditory nerve, allowing people to hear sound.

[0039] The speaker of this application has the following structural features:

[0040] ①The vibration component adopts a double vibration plate structure.

[0041] In order to achieve the purpose of improving performance, the vibration plate is designed to be two: a first vibration plate 2 and a second vibration plate 3, which are arranged in parallel and spaced apart. In this application, the first vibration plate 2 and the second vibration plate 3 are made of different materials to have different compliances. Among them, the compliance of the first vibration plate 2 is less than the compliance of the second vibration plate 3. In terms of material selection, the first vibration plate 2 can be, for example, a silicon steel vibration plate or a stainless steel vibration plate, and the second vibration plate 3 can be, for example, a phosphor copper vibration plate.

[0042] The first vibrating plate 2 and the second vibrating plate 3 have different compliances, which together constitute the compliance of the vibration assembly. Let's denote the compliance of the entire vibration assembly as A, the compliance of the first vibrating plate 2 as B, and the compliance of the second vibrating plate 3 as C. The order of A, B, and C varies at different frequencies. The effects of external signals and the differing compliances of the two vibrating plates result in different vibration characteristics, causing the vibration assembly to vibrate differently across different frequency ranges, thereby improving its performance.

[0043] At low frequencies, the compliant force impedance of the entire vibration assembly is greater than the force impedance of the first vibration plate 2, resulting in the vibration assembly moving as a whole; at high frequencies, the compliant force impedance of the entire vibration assembly is smaller than the force impedance of the first vibration plate 2, resulting in the second vibration plate 3 mainly moving, while the first vibration plate 2 remains almost motionless (the vibration amplitude is extremely small); using this dual vibration plate design, the frequency range can be extended to high frequencies by almost an octave depending on the audio signal and impedance characteristics, and in the high frequency range, the power capacity is not impaired due to the addition of the second vibration plate 3, but the high frequency is extended instead.

[0044] It should be noted that the high frequency and low frequency mentioned in this article should be understood according to the actual business scenario and do not set an absolute range. For example, low frequency can be understood as less than 200Hz or 160Hz, and high frequency can be understood as greater than 5KHz or 5120Hz.

[0045] ②The transducer assembly may adopt a dual voice coil structure.

[0046] Optionally, the speaker of the present application adopts a dual voice coil structure, that is, there are two voice coils 7.

[0047] In one optional embodiment, a dual voice coil includes a first voice coil and a second voice coil, with the first voice coil coaxially mounted outside the second voice coil. In other words, the dual voice coil configuration involves two coaxially wound voice coils, one inside and one outside. Optionally, the first voice coil has a mass of m1, an inductance of L1, and a resistance of rE1, serving as the outer voice coil; the second voice coil has a mass of m2, an inductance of L2, and a resistance of rE2, serving as the inner voice coil.

[0048] In another optional embodiment, the dual voice coil includes a first voice coil and a second voice coil, the first and second voice coils being coaxially arranged and axially spaced apart. In other words, another form of the dual voice coil is one in which the two voice coils are coaxially spaced apart, located above and below each other. Optionally, the first voice coil has a mass of m1, an inductance of L1, and a resistance of rE1, serving as the lower voice coil; the second voice coil has a mass of m2, an inductance of L2, and a resistance of rE2, serving as the upper voice coil.

[0049] In the embodiment of the present application, the dual voice coils can be connected in series or in parallel. When the first and second voice coils are connected in parallel, they function as two separate, independent units, enabling the system to achieve excellent frequency response over a wide range. When the first and second voice coils are connected in series, they operate as a single, independent unit.

[0050] ③Shunt capacitor.

[0051] Optionally, the speaker of the present application may further include a shunt capacitor C E Optionally, the shunt capacitor may be connected externally.

[0052] refer to Figure 2 In some optional embodiments, the external shunt capacitor C E The connection method is as follows: A is the current input terminal of the second voice coil L2, B is the current outflow terminal of the second voice coil L2; C is the current input terminal of the first voice coil L1, D is the current outflow terminal of the first voice coil L1; Among them, B and C are connected, and through the shunt capacitor C E And D is connected. That is, the first voice coil L1 is connected to the shunt capacitor C E After being connected in parallel, it is connected in series with the second voice coil L2.

[0053] The result is a dual voice coil system at low frequencies, and a single voice coil (with only L2 active) at high frequencies, resulting in smooth overlap across the entire frequency band and a smoother frequency response. Typically, radiation resistance is constant above the critical impedance frequency. To achieve uniform output within this range, the system's impedance should ideally be independent of frequency. This is why typical speakers (receivers) incorporate appropriate wrinkles (patterns) in their paper cones to reduce effective mass impedance. Compared to a typical single voice coil system, a dual voice coil system reduces both the effective mass and electrical impedance at high frequencies. By adopting this structure, the dual voice coil system switches to a single voice coil at high frequencies, reducing the effective mass of the voice coil, resulting in a more uniform output and a smoother frequency response.

[0054] In some optional implementations, the external capacitor C E The connection can also be done like this: external capacitor CE Instead of using a single capacitor, use two capacitors connected in parallel. The parallel capacitance is generally chosen between 10pF and 100pF, for example, 10pF and 33pF. Of course, to account for the effects of distributed capacitance, some adjustments can be made, such as 27pF and 68pF. The specific optimal value can be determined through experimentation. This design of two parallel capacitors as external capacitors will reduce the speaker's Q factor, but at the same time, due to the changes in second and third harmonics, it will improve subjective listening performance.

[0055] ④Up and down contact fulcrum

[0056] Optionally, the upper and lower contact fulcrums on the second vibration plate 3 may be of different sizes. For example, the upper contact fulcrum 5 for contacting the human body may be larger than the lower contact fulcrum 4 to increase human comfort.

[0057] ⑤Packaging

[0058] Optionally, the housing 1 of the speaker of the present application can be packaged by crimping or gluing when the size is small; when the size is large, the housing 1 and the inner pipe cavity 9 can be fixed with countersunk screws.

[0059] This application discloses a dual-vibration plate bone conduction speaker. The speaker's vibration assembly utilizes dual vibrating plates, significantly extending the frequency response range and smoothing its frequency response characteristics, thereby significantly improving speaker performance. Furthermore, the speaker's transducer assembly can utilize a dual voice coil structure to further improve the system's vibration characteristics. Furthermore, the speaker can also incorporate an external capacitor as a shunt capacitor to further enhance performance.

[0060] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0061] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A double-vibrating plate bone conduction speaker, characterized in that: include: shell; a transducer assembly, disposed in the housing, and configured to generate vibrations under the stimulation of an electrical signal; a vibration component, disposed in the housing, for transmitting the vibration generated by the transducer component to a contacting human body; Wherein, the vibration component includes: a first vibrating plate connected to the transducer assembly; a second vibration plate, spaced apart from the first vibration plate; a lower contact fulcrum, provided on the lower surface of the second vibrating plate and in contact with the first vibrating plate, for transmitting the vibration of the first vibrating plate to the second vibrating plate; an upper contact fulcrum, provided on the upper surface of the second vibrating plate, for transmitting the vibration of the second vibrating plate to the human body in contact; The compliance of the first vibrating plate is smaller than the compliance of the second vibrating plate; At low frequencies, the force impedance of the vibration component is greater than the force impedance of the first vibration plate, and the vibration component moves as a whole; at high frequencies, the force impedance of the vibration component is less than the force impedance of the first vibration plate, and it is mainly the second vibration plate that moves, while the first vibration plate remains almost motionless.

2. The dual-vibration plate bone conduction speaker according to claim 1, characterized in that: The transducer assembly includes a magnet and a voice coil. The magnet is bonded to the first vibration plate, and the voice coil surrounds the magnet.

3. The dual-vibration plate bone conduction speaker according to claim 2, characterized in that: The voice coil includes a first voice coil and a second voice coil, and the first voice coil is coaxially sleeved outside the second voice coil.

4. The dual-vibration plate bone conduction speaker according to claim 2, characterized in that: The voice coil includes a first voice coil and a second voice coil. The first voice coil and the second voice coil are coaxially arranged and spaced apart from each other in an axial direction.

5. The dual-vibration plate bone conduction speaker according to claim 2, characterized in that: The voice coil includes a first voice coil and a second voice coil, and the first voice coil and the second voice coil are connected in parallel.

6. The double-vibration plate bone conduction speaker according to claim 2, characterized in that: The voice coil includes a first voice coil and a second voice coil, and the first voice coil and the second voice coil are connected in series.

7. The double-vibration plate bone conduction speaker according to claim 6, characterized in that: The voice coil further includes a shunt capacitor, and the first voice coil is connected in parallel with the shunt capacitor and then in series with the second voice coil.

8. The double-vibration plate bone conduction speaker according to any one of claims 1 to 7, characterized in that: Also includes: An inner pipe cavity is arranged in the outer shell, and the transducer component and the vibration component are arranged in the inner pipe cavity.

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