Sound generating device and electronic device

Abstract

The present invention discloses a sound-generating device and an electronic device. The sound-generating device includes a device housing, and a receiving cavity is formed in the device housing; a magnetic circuit system and a vibration system are accommodated in the receiving cavity, and the magnetic circuit system includes a yoke, a central magnet arranged on the yoke, and a magnetic conductive plate arranged on the central magnet, wherein the magnetic circuit system has a hollow area along the vibration direction of the vibration system, and a heat sink is arranged in the hollow area. One technical effect of the present invention is that it can achieve good heat dissipation and cooling effects on the sound-generating device in operation.

Description

Technical Field

[0001] The present invention relates to the technical field of acoustic devices, and more specifically, to a sound-generating device and an electronic device. Background Art

[0002] As people's requirements for quality of life continue to improve, high-quality music enjoyment has gradually become popular among the public. Therefore, sound-generating devices for playing audio have been widely used in smart mobile devices such as smartphones, tablets, laptops, and various smart wearable devices. A sound-generating device is a transducer that can convert electrical signals into sound signals. The acoustic performance and reliability of the sound-generating device are particularly important.

[0003] Nowadays, with the rapid development of smart phones, the application scenarios of smart phones are becoming more and more extensive, and users have higher and higher requirements for mobile phones in all aspects. When using a mobile phone, whether playing games, watching videos or listening to music, high-quality sound effects are usually required, which puts higher requirements on the sound device used in the smart phone. Not only is the sound device required to be loud, but the sound device is also required to have good sound quality. However, the high loudness of the sound device is often accompanied by high power. As far as the existing sound device is concerned, its power has been increased to about 1W, but the sound efficiency of the sound device itself is relatively low, and most of the input power is converted into heat. In fact, inside the sound device, many components have poor temperature resistance and can usually withstand a temperature of about 110°C. In order to prevent the components in the sound device from being damaged or damaged due to high temperature, the temperature of the sound device is usually limited. However, the existing protection scheme usually brings two disadvantages: (1) The acoustic performance of the sound device is limited, resulting in its maximum loudness cannot be exerted. (2) The protection effect is not ideal, and the heat source - the voice coil is still very easy to burn.

[0004] Therefore, it is very necessary to study a new technology to solve the problems existing in the prior art. Summary of the invention

[0005] An object of the present invention is to provide a new technical solution for a sound-generating device and an electronic device.

[0006] According to a first aspect of the present invention, a sound-generating device is provided, characterized in that: it comprises a device housing, a receiving cavity is formed in the device housing; a magnetic circuit system and a vibration system are received in the receiving cavity,

[0007] The magnetic circuit system includes a yoke, a central magnet arranged on the yoke, and a magnetic conductive plate arranged on the central magnet, wherein the magnetic circuit system has a hollow area along the vibration direction of the vibration system, and a heat sink is arranged in the hollow area.

[0008] Optionally, the heat conductivity of the heat sink is greater than 150 W / mk.

[0009] Optionally, the heat sink is arranged in the hollow area by gluing, riveting or laser welding.

[0010] Optionally, the hollow area is a through hole that penetrates the magnetic conductive plate, the central magnet and the magnetic yoke, and the heat sink is accommodated and fixed in the through hole.

[0011] Optionally, the heat sink is a copper block or an aluminum block, and the shape and size of the heat sink are compatible with the shape and size of the through hole.

[0012] Optionally, the hollow area includes a first channel penetrating the magnetic conductive plate and the central magnet, and a second channel penetrating the magnetic yoke, the first channel is connected to the second channel, and an inner diameter of the first channel is smaller than an inner diameter of the second channel;

[0013] The heat sink is accommodated and fixed in both the first channel and the second channel.

[0014] Optionally, the heat sink comprises a first heat sink and a second heat sink, and the first heat sink and the second heat sink are combined together to form a T-shaped structure;

[0015] The shape and size of the first heat dissipation portion are adapted to the shape and size of the first channel;

[0016] The shape and size of the second heat dissipation portion are matched with the shape and size of the second channel.

[0017] Optionally, the first heat dissipation portion and the second heat dissipation portion are made of the same material, which is copper material or aluminum material.

[0018] Optionally, the hollow area is a hole formed on the yoke, and the heat sink is accommodated and fixed in the hole.

[0019] Optionally, the heat sink is a copper sheet or an aluminum sheet, and the shape and size of the heat sink are compatible with the shape and size of the hole.

[0020] According to a second aspect of the present invention, there is provided an electronic device, comprising a sound generating device as described in any one of the above; and

[0021] The product body, the sound-generating device is arranged inside the product body.

[0022] The sound-generating device provided in the embodiment of the present invention has improved the magnetic circuit system therein, and a heat sink is embedded in the magnetic circuit system so that the magnetic circuit system has good heat dissipation performance. When the sound-generating device is in a long-term working state, the heat generated inside the sound-generating device can be dissipated to the outside in time to avoid damage to parts due to excessive temperature inside the sound-generating device, which helps to extend the service life of the sound-generating device. The technical tasks to be achieved or the technical problems to be solved by the present invention are never thought of or anticipated by those skilled in the art, so the present invention is a new technical solution.

[0023] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0025] Figure 1 This is a schematic diagram of the heat dissipation principle of a conventional sound-generating device.

[0026] Figure 2 It is a schematic diagram of the internal structure of a conventional sound-generating device.

[0027] Figure 3 It is a schematic diagram of the internal structure of a sound-generating device provided according to an embodiment of the present invention.

[0028] Figure 4 Schematic diagram of the structure of a heat sink provided according to an embodiment of the present invention.

[0029] Figure 5 It is a schematic diagram of the internal structure of a sound-generating device provided according to another embodiment of the present invention.

[0030] Figure 6 is a schematic structural diagram of a heat sink provided according to another embodiment of the present invention.

[0031] Figure 7 It is a schematic diagram of the internal structure of a sound-generating device provided according to yet another embodiment of the present invention.

[0032] Figure 8 is a schematic structural diagram of a heat sink provided according to yet another embodiment of the present invention.

[0033] Fig. 9 This is a table of sensitivity and temperature rise of a sound-generating device provided according to an embodiment of the present invention.

[0034] Fig.10 The figure is a temperature rise curve diagram provided according to an embodiment of the present invention.

[0035] Description of reference numerals:

[0036] 1-yoke, 2-magnet, 3-magnetic plate, 4-voice coil, 5-heat sink, 6-hollow area, 61-first channel, 62-second channel. DETAILED DESCRIPTION

[0037] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0038] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0039] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0040] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0041] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0042] According to one embodiment of the present invention, a sound-generating device is provided. The sound-generating device can be applied to various types of electronic products such as mobile phones, laptop computers, tablet computers, VR devices, AR devices, and smart wearable devices. The sound-generating device provided by the present invention has good heat dissipation performance and will not have a phenomenon of excessive temperature due to long-term use.

[0043] The specific structure of the sound-generating device provided in the embodiment of the present invention is further described below.

[0044] The embodiment of the present invention provides a sound generating device, such as Figure 3 , Figure 5 and Figure 7 As shown, it includes a device housing, and a receiving cavity is formed in the device housing; it also includes a magnetic circuit system and a vibration system, and the magnetic circuit system and the vibration system are accommodated in the receiving cavity. The magnetic circuit system includes a magnetic yoke 1, a central magnet arranged on the magnetic yoke 1, and a magnetic conductive plate 3 arranged on the central magnet, wherein the magnetic circuit system is provided with a hollow area 6 along the vibration direction of the vibration system, and a heat sink 5 is arranged in the hollow area 6.

[0045] When the sound device is in working state, such as Figure 1 and Figure 2 As shown, the voice coil 4 in the vibration system as a heat source will generate a large amount of heat, and this heat will first be transferred to the magnetic circuit system, and then the magnetic circuit system will dissipate the heat to the outside to achieve heat dissipation and cooling of the sound-generating device. However, in the existing sound-generating device, the heat dissipation effect of the magnetic circuit system is not good, and it is impossible to quickly and timely dissipate the heat generated inside the sound-generating device to the outside, which will cause the temperature inside the sound-generating device to be too high.

[0046] The sound-generating device provided in the embodiment of the present invention improves the structure of the magnetic circuit system, and a heat sink 5 with good heat dissipation performance is embedded in the magnetic circuit system, giving the magnetic circuit system good heat dissipation performance. Specifically, when the sound-generating device is in a working state, the heat generated by the voice coil 4 is transferred to the magnetic circuit system, and the magnetic circuit system can quickly and timely conduct the heat inside the sound-generating device to the outside and dissipate it into the air with the help of the built-in heat sink 5, so as to achieve cooling of the sound-generating device.

[0047] In the sound-generating device provided by the embodiment of the present invention, the magnetic circuit system is provided with a hollow area 6 along the vibration direction of the vibration system, and a heat sink 5 is provided in the hollow area 6. Specifically, the inventors have found that by providing hollow areas on the yoke 1, the central magnet and the magnetic conductive plate 3, the loss of the BL value (the length L of the wire of a certain number of turns multiplied by the magnetic flux density B per unit area) is very small, and will not affect the acoustic performance of the present sound-generating device.

[0048] In one example of the present invention, the heat transfer coefficient of the heat sink is greater than 150W / mk. The heat transfer coefficient of a traditional magnetic circuit system is generally less than 80W / mk, which causes the heat generated by the voice coil to be unable to be quickly transferred out during operation of the sound-generating device, resulting in the risk of the voice coil being burned due to excessive temperature. The heat sink in the present invention has a heat transfer coefficient greater than 150W / mk, and the heat sink can quickly transfer the heat generated by the voice coil to the outside air through the magnetic circuit system to prevent the voice coil from being burned. The heat sink of the present invention is not limited to a material, and preferably a heat sink made of metal, such as copper and aluminum, has a significant effect on reducing the temperature inside the sound-generating device.

[0049] In one example of the present invention, Figure 3As shown, the magnetic circuit system is provided with a hollow area 6 in the vibration direction of the vibration system, wherein the hollow area 6 is a through hole penetrating the magnetic plate 3, the central magnet of the magnet 2 and the yoke 1, and a heat sink 5 is fixed in the through hole. The magnet 2 includes a central magnet and a side magnet, and in some products, the side magnet and the yoke are set as an integral structure. In this example, the heat sink 5 is in direct contact with the magnetic plate 3, the central magnet and the yoke 1, and the heat on these components can be quickly transferred to the heat sink 5. The heat sink 5 can dissipate the heat to the outside in time due to its good heat dissipation performance, so as to reduce the temperature inside the sound-generating device.

[0050] like Figure 3 and Figure 4 As shown, in this example, the heat sink 5 can be, for example, a metal block. More preferably, the heat sink 5 can be, for example, a copper block or an aluminum block. The thermal conductivity of copper material is about 429W / mk, and the thermal conductivity of aluminum material is about 237W / mk. Conventional yokes are usually made of SPCC material, and the thermal conductivity of SPCC material is about 80W / mk. From the comparison of thermal conductivity coefficients, it can be seen that the thermal conductivity of copper and aluminum materials is much higher than that of SPCC materials, which is very conducive to heat dissipation. In addition, in order to embed the heat sink 5 well into the hollow area 6, the shape and size of the heat sink 5 in this example should be compatible with the shape and size of the through hole. For example, the shape of the heat sink 5 can be cylindrical, cubic, tetrahedral, etc., and those skilled in the art can flexibly adjust it according to the shape and size of the hollow area 6, and the present invention is not limited to this.

[0051] In one example of the present invention, Figure 5 As shown, the magnetic circuit system is provided with a hollow area 6 along the z-axis direction of the magnetic circuit, wherein the hollow area 6 includes a first channel 61 penetrating the magnetic conductive plate 3 and the central magnet, and a second channel 62 penetrating the magnetic yoke 1, the first channel 61 is connected to the second channel 62, and the inner diameter of the first channel 61 is smaller than the inner diameter of the second channel 62; a heat sink 5 is fixedly received in the first channel 61 and the second channel 62. In this example, the structure of the heat sink 5 is as follows: Figure 6 As shown, it includes a first heat dissipation part and a second heat dissipation part, and the first heat dissipation part and the second heat dissipation part are combined to form a T-shaped structure. Among them, the shape and size of the first heat dissipation part should be compatible with the shape and size of the first channel 61, and the shape and size of the second heat dissipation part should be compatible with the shape and size of the second channel 62. In addition, the material of the first heat dissipation part and the second heat dissipation part can be the same, for example, both are copper or aluminum. Of course, the materials of the first heat dissipation part and the second heat dissipation part can also be different, and those skilled in the art can flexibly adjust according to specific needs to achieve a better heat dissipation effect.

[0052] It should be noted that in the above example, Figure 5 and Figure 6 As shown, for the hollow area 6, the inner diameter of the second channel 62 provided on the yoke 1 is relatively large, and a larger heat sink, namely, a second heat sink, can be provided inside the hollow area 6. When the sound-generating device is working, after the heat generated by the voice coil 4 is transferred to the yoke 1, the second heat sink with a larger size embedded in the yoke 1 can dissipate the heat to the outside more quickly. This is because the second heat sink has a larger size, which is equivalent to having a larger heat dissipation area, so that faster heat dissipation can be achieved, thereby improving heat dissipation efficiency.

[0053] In the above example, if Fig. 9 As shown, the inventor conducted a simulation experiment with a speaker unit with a size of 16*12*2.5mm and obtained Fig. 9 From the table, it can be seen that the temperature rise data is significantly reduced by setting a hollow area in the magnetic circuit system and adding a heat sink in the hollow area. Fig.10 The temperature rise curve obtained by actual verification in the present invention shows that the temperature rise is reduced by 2.5 degrees, which shows that the present invention can achieve rapid heat dissipation and improve heat dissipation efficiency.

[0054] In one example of the present invention, Figure 7 As shown, the magnetic circuit system is provided with a hollow area 6 along the vibration direction of the vibration system, wherein the hollow area 6 is a hole formed on the yoke 1, and a heat sink 5 is fixedly received in the hole. Figure 8 As shown, the heat sink 5 may be, for example, a metal sheet. Preferably, the heat sink 5 may be, for example, a copper sheet or an aluminum sheet. The shape and size of the heat sink 5 are adapted to the shape and size of the hole, so that the heat sink 5 and the yoke 1 are well combined.

[0055] In the above example, if Figure 7 and Figure 8 As shown, the hollow area 6 is a hole formed only on the yoke 1, and the corresponding heat sink 5 is a sheet structure. When the sound-generating device is working, the heat generated by the voice coil 4 is transferred to the yoke 1, and the yoke 1 dissipates the heat with the help of the heat sink 5 to achieve cooling. The hollow area 6 is formed in a simple manner, and the structure of the heat sink 5 is also relatively simple, so that the overall manufacturing process is relatively simple, which can reduce the production cost.

[0056] The heat sink 5 is embedded in the hollow area 6 in the present invention. In order to stably and firmly set the heat sink 5 in the hollow area 6, the heat sink 5 can be glued in the hollow area 6, for example. This connection method is simple and has good firmness. The heat sink can also be fixed in the hollow area by riveting. Or the heat sink can be welded in the hollow area by laser welding. There is no limitation on the setting method of the heat sink and the hollow area, and the best connection method can be selected according to the specific situation.

[0057] In the sound-generating device provided by an embodiment of the present invention, the magnet 2 includes a central magnet and a side magnet, and the central magnet and the side magnet are arranged at an interval to form a magnetic gap therebetween. The vibration system includes a voice coil 4 and a diaphragm. One end of the voice coil 4 is connected to the diaphragm, and the other end of the voice coil 4 is inserted in the magnetic gap. In the present invention, the voice coil 4 serves as a heat source, and the heat generated by the voice coil 4 can be quickly and timely dissipated to the outside through the heat sink 5 embedded in the magnetic circuit system to reduce the internal temperature and avoid the phenomenon of the voice coil 4 being burned.

[0058] According to another aspect of the present invention, an electronic device is provided, wherein the electronic device comprises the sound-generating device as described in any one of the above items, and a product body, wherein the sound-generating device is arranged inside the product body.

[0059] The electronic device may be, for example, a mobile phone, a laptop computer, a tablet computer, a VR device, a smart wearable device, etc., and the present invention is not limited to this.

[0060] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A sound-generating device, characterized in that: The device comprises a housing, wherein a receiving cavity is formed in the housing; the receiving cavity contains a magnetic circuit system and a vibration system, The magnetic circuit system includes a magnetic yoke, a central magnet arranged on the magnetic yoke, and a magnetic conductive plate arranged on the central magnet, wherein the magnetic circuit system is provided with a hollow area along the vibration direction of the vibration system, and a heat sink is arranged in the hollow area; The hollow area includes a first channel penetrating the magnetic conductive plate and the central magnet, and a second channel penetrating the magnetic yoke, the first channel is connected to the second channel, and the inner diameter of the first channel is smaller than the inner diameter of the second channel; The heat sink is accommodated and fixed in the first channel and the second channel; The heat sink comprises a first heat sink and a second heat sink, wherein the first heat sink and the second heat sink are combined together to form a T-shaped structure; The shape and size of the first heat dissipation portion are adapted to the shape and size of the first channel; The shape and size of the second heat dissipation portion are adapted to the shape and size of the second channel; The first heat dissipation portion and the second heat dissipation portion are made of different materials.

2. The sound generating device according to claim 1, characterized in that: The heat conductivity of the heat sink is greater than 150 W / mk.

3. The sound-generating device according to claim 1, characterized in that: The heat sink is arranged in the hollow area by gluing, riveting or laser welding.

4. An electronic device, characterized in that: A sound-generating device comprising any one of claims 1 to 3; and The product body, the sound-generating device is arranged inside the product body.

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