Sound generating devices and electronic equipment

Abstract

The present application discloses a sound-generating device and an electronic device. The sound-generating device includes a piezoelectric sheet, a connecting sheet and a mass member, wherein the cross section of the piezoelectric sheet along the direction perpendicular to the thickness includes a first side, a second side, a third side and a fourth side; wherein the first side and the second side are arranged oppositely along the first direction, and the first side and the second side are arc-shaped; the third side and the fourth side are arranged oppositely along the second direction, and the third side and the fourth side are straight-line-shaped; the piezoelectric sheet has a first surface arranged along its thickness direction; the connecting sheet is laminated and connected to the first surface of the piezoelectric sheet; the mass member is located on the side of the connecting sheet away from the piezoelectric sheet, and the mass member is flexibly connected to the connecting sheet.

Description

Technical Field

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

[0002] With the development of science and technology and the improvement of living standards, various electronic products have gradually entered thousands of households and become necessities of people's lives; sound-generating devices are installed in many electronic products, such as smart phones, laptops, tablets, etc.

[0003] In recent years, many electronic products have been increasingly trending towards thinner and smaller sizes. However, the traditional electromagnetic voice coil driven sound device is placed in the electronic product in the form of a module, which is large in size and not conducive to the thinner and lighter development of electronic products. Although the piezoelectric driven sound device occupies a smaller space, the conventional piezoelectric driven sound device has poor acoustic performance, especially the poor low-frequency acoustic performance.

[0004] In view of this, a new technical solution needs to be proposed to improve the low-frequency acoustic performance of the piezoelectric driven sound-generating device. Summary of the invention

[0005] One purpose of the present application 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 application, a sound-generating device is provided, the sound-generating device comprising:

[0007] A piezoelectric sheet, wherein a cross section of the piezoelectric sheet along a direction perpendicular to the thickness direction comprises a first side, a second side, a third side and a fourth side; wherein the first side and the second side are arranged opposite to each other along a first direction, and the first side and the second side are arc-shaped; the third side and the fourth side are arranged opposite to each other along a second direction, and the third side and the fourth side are straight-line-shaped; the piezoelectric sheet has a first surface arranged along its thickness direction;

[0008] A connecting sheet, the connecting sheet being laminated and connected to the first surface of the piezoelectric sheet;

[0009] The mass member is located on a side of the connecting sheet away from the piezoelectric sheet, and the mass member is flexibly connected to the connecting sheet.

[0010] Optionally, the first side and the second side are arc-shaped with equal radius, and the third side and the fourth side are straight lines with equal length; the diameter of the first side is greater than the length of the third side.

[0011] Optionally, the ratio of the thickness of the piezoelectric sheet to the thickness of the connecting sheet is 2:1.

[0012] Optionally, the connecting piece is made of a polymer material or a lightweight foam metal.

[0013] Optionally, along the thickness direction of the piezoelectric sheet, the projection of the piezoelectric sheet is located within the projection range of the connecting sheet.

[0014] Optionally, the connecting piece is circular, and a central axis of the connecting piece coincides with a central axis of the piezoelectric piece.

[0015] Optionally, the radius of the connecting piece is at least 1 mm larger than the radius of the first side.

[0016] Optionally, the sound-generating device further includes a foam layer, and the foam layer is arranged between the mass member and the connecting sheet.

[0017] Optionally, the thickness of the foam layer is greater than or equal to 0.1 mm.

[0018] Optionally, the mass member is a layered structure; or, the mass member includes a plurality of mass blocks arranged at intervals.

[0019] According to a second aspect of the present application, an electronic device is provided, wherein the electronic device comprises the sound generating device as described in the first aspect.

[0020] The sound-emitting device provided in the embodiment of the present application not only has excellent high-frequency acoustic performance, but also due to the special shape of the piezoelectric piece, it is easier to deform, has a larger amplitude, and is easier to produce a better vibration effect, which is beneficial to improving the low-frequency acoustic performance of the sound-emitting device.

[0021] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and, together with the description, serve to explain the principles of the application.

[0023] Figure 1 is a schematic diagram of the main structure of a sound-generating device according to an embodiment of the present application;

[0024] Figure 2a is a schematic diagram of the three-dimensional structure of a sound-generating device according to an embodiment of the present application Figure 1 ;

[0025] Figure 2b yes Figure 2a The enlarged schematic diagram of point A in the middle;

[0026] Figure 3ais a second schematic diagram of the three-dimensional structure of a sound-generating device according to an embodiment of the present application;

[0027] Figure 3b yes Figure 3a A magnified schematic diagram of point B in the middle.

[0028] Description of reference numerals:

[0029] 1. Sound-generating device; 11. Piezoelectric sheet; 111. First side; 112. Second side; 113. Third side; 114. Fourth side; 12. Connecting sheet; 13. Mass member; 14. Foam layer. DETAILED DESCRIPTION

[0030] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, 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 application.

[0031] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present application, its application, or uses.

[0032] 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.

[0033] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0034] 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.

[0035] Reference Figure 1 to Figure 3bAs shown, according to an embodiment of the present application, a sound-generating device 1 is provided. The sound-generating device 1 includes a piezoelectric sheet 11, a connecting sheet 12, and a mass member 13. The cross section of the piezoelectric sheet 11 along a direction perpendicular to the thickness includes a first side 111, a second side 112, a third side 113, and a fourth side 114; wherein the first side 111 and the second side 112 are arranged opposite to each other along a first direction, and the first side 111 and the second side 112 are arc-shaped, specifically, the first side 111 and the second side 112 are arc-shaped with equal radius; the third side 113 and the fourth side 114 along the second direction They are arranged relative to each other, and the third side 113 and the fourth side 114 are straight lines, specifically, the third side 113 and the fourth side 114 are straight lines of equal length; specifically, the diameter of the first side 111 is greater than the length of the third side 113; the piezoelectric sheet 11 has a first surface arranged along its thickness direction; the connecting sheet 12 is stacked and connected to the first surface of the piezoelectric sheet 11; the mass member 13 is located on the side of the connecting sheet 12 away from the piezoelectric sheet 11, and the mass member 13 is flexibly connected to the connecting sheet 12.

[0036] Reference Figure 1 As shown, the first direction is Figure 1 The a direction in the second direction is Figure 1 The b direction in .

[0037] In the sound-generating device 1 provided in the embodiment of the present application, the vibration action is transmitted from the piezoelectric sheet 11 to the connecting sheet 12 and then to the mass member 13. The piezoelectric sheet 11 is the core driving element of the sound-generating device, and its cross-section is designed to be a special geometric shape, specifically including a first side 111, a second side 112, a third side 113 and a fourth side 114; wherein the first side 111 and the second side 112 are arranged relative to each other along a first direction, and are both arc-shaped with equal radius, and such a design helps to produce uniform deformation when subjected to force. The third side 113 and the fourth side 114 are arranged relative to each other along a second direction perpendicular to the first direction, and are straight lines of equal length, ensuring the stability of the piezoelectric sheet in a specific direction. Importantly, the diameter of the first side 111 (i.e., the diameter of the arc) is greater than the length of the third side 113, and such a size design optimizes the vibration effect of the piezoelectric sheet. More specifically, the piezoelectric sheet 11 is actually a circle with an identical arch structure removed from both sides. The radius of the circle is the radius of the first side 111 and the second side 112, and the third side 113 and the fourth side 114 are the chords of the circle that do not pass through the center. Compared with a circular structure, the piezoelectric sheet 11 is more likely to deform and has a larger amplitude, which is beneficial to improving the low-frequency acoustic performance of the sound-generating device 1; and compared with a circular structure, the piezoelectric sheet 11 is not easy to produce an anti-resonant vibration form, which is beneficial to improving the high-frequency acoustic performance of the sound-generating device 1. In addition, compared with a rectangular structure, the arc shape of the first side 111 and the second side 112 of the piezoelectric sheet 11 extends more toward the outside, so that it is easier to produce a better vibration effect, which is beneficial to improving the low-frequency acoustic performance of the sound-generating device 1.

[0038] The piezoelectric sheet 11 also has a first surface arranged along its thickness direction, which is used to connect with the connecting sheet 12. The connecting sheet 12 is stacked and connected to the first surface of the piezoelectric sheet 11, and plays a role in transmitting vibration energy. The mass member 13 is located on the side of the connecting sheet 12 away from the piezoelectric sheet 11, and the connecting sheet 12 is connected to the mass member 13 by a flexible connection, which can reduce the matching constraints and prevent the vibration deformation of the piezoelectric sheet 11 and the connecting sheet 12 from being affected. The addition of the mass member 13 increases the total mass of the system, thereby generating a greater inertial force when the piezoelectric sheet vibrates, thereby enhancing the sound effect.

[0039] Furthermore, the piezoelectric sheet 11 and the connecting sheet 12 are both thin sheet structures; optionally, the total thickness of the piezoelectric sheet 11 and the connecting sheet 12 is about 0.3 mm, which is very suitable for use in electronic products such as smart phones. In addition, the matching mass parts of the driving assembly composed of the thinner piezoelectric sheet 11 and the connecting sheet 12 are hard-bonded to further ensure the low-frequency acoustic performance, and the resonant frequency of the driving assembly composed of the piezoelectric sheet 11 and the connecting sheet 12 is about 600 Hz. After the sound-generating device 1 is installed in an electronic product, the periphery of the connecting sheet 12 is fixed to other components in the electronic product, such as the housing.

[0040] In summary, the sound-generating device 1 provided in the embodiment of the present application is not only small in size and occupies a small space, but also its application in electronic products is conducive to the miniaturization design of electronic products; and the sound-generating device has excellent low-frequency acoustic performance and high-frequency acoustic performance.

[0041] Reference Figure 1 to Figure 3b As shown, in one embodiment, the ratio of the thickness of the piezoelectric sheet 11 to the thickness of the connecting sheet 12 is 2:1.

[0042] In this specific example, the ratio of the thickness of the piezoelectric sheet 11 to the thickness of the connecting sheet 12 is 2:1. Such a ratio design can ensure that the piezoelectric sheet 11 can fully deform and stimulate the piezoelectric effect when subjected to external force, and the connecting sheet 12 can also effectively transmit vibration. Moreover, such a ratio design not only ensures the reliability of the piezoelectric sheet 11 driving the connecting sheet 12 to vibrate, but also avoids the loss of vibration energy caused by the connecting sheet being too thick. For example, the thickness of the piezoelectric sheet 11 is 0.2 mm, the thickness of the connecting sheet 12 is 0.1 mm, and the total thickness of the driving assembly composed of the piezoelectric sheet 11 and the connecting sheet 12 is about 0.3 mm, which is beneficial to improving the low-frequency acoustic performance of the sound-generating device.

[0043] Reference Figure 1 to Figure 3b As shown, in one embodiment, the connecting piece 12 is made of a polymer material or a lightweight foam metal.

[0044] In this specific example, the material of the connecting piece 12 can be a polymer material or a lightweight foam metal, which has good flexibility and lightweight properties, can effectively transmit the vibration generated by the piezoelectric piece 11, and reduce the weight of the entire sound-generating device. When the material of the connecting piece 12 is a lightweight foam metal, its Young's modulus is about 11 GPa.

[0045] Reference Figure 1 to Figure 3b As shown, in one embodiment, along the thickness direction of the piezoelectric sheet 11 , the projection of the piezoelectric sheet 11 is located within the projection range of the connecting sheet 12 .

[0046] In this specific example, along the thickness direction of the piezoelectric sheet 11, the projection of the piezoelectric sheet 11 is located within the projection range of the connecting sheet 12, that is, the connecting sheet 12 completely covers the piezoelectric sheet 11 and the edge of the connecting sheet 12 protrudes from the edge of the piezoelectric sheet 11, thereby providing a certain elastic deformation space for the driving assembly composed of the piezoelectric sheet 11 and the connecting sheet 12.

[0047] Reference Figure 1 to Figure 3b As shown, in one embodiment, the connecting piece 12 is circular, and the central axis of the connecting piece 12 coincides with the central axis of the piezoelectric piece 11 .

[0048] In this specific example, the circular connecting piece 12 is coaxially arranged with the quasi-circular piezoelectric piece 11, thereby ensuring that the driving assembly composed of the piezoelectric piece 11 and the connecting piece 12 can vibrate and deform uniformly and stably.

[0049] Reference Figure 1 to Figure 3b As shown, in one embodiment, the radius of the connecting piece 12 is at least 1 mm larger than the radius of the first side edge 111 .

[0050] In this specific example, the edge of the connecting sheet 12 is protruded by at least 1 mm in width compared to the edge of the piezoelectric sheet 11 , thereby providing sufficient elastic deformation space for the driving assembly composed of the piezoelectric sheet 11 and the connecting sheet 12 .

[0051] Reference Figure 1 to Figure 3b As shown, in one embodiment, the sound-generating device further includes a foam layer 14 , and the foam layer 14 is disposed between the mass member 13 and the connecting sheet 12 .

[0052] In this specific example, the foam layer 14 is used to achieve a flexible connection between the mass member 13 and the connecting piece 12 , which can further buffer and transmit vibrations, thereby ensuring that matching constraints are reduced and preventing effects on vibration deformation of the piezoelectric piece 11 and the connecting piece 12 .

[0053] Reference Figure 1 to Figure 3b As shown, in one embodiment, the thickness of the foam layer 14 is greater than or equal to 0.1 mm.

[0054] In this specific example, the thickness of the foam layer 14 is greater than or equal to 0.1 mm, which ensures the flexibility of the foam layer 14 and avoids excessive absorption of vibration energy. Optionally, the foam layer 14 is connected to the connecting piece 12 and the mass member 13 through silicone, which can ensure the reliability of the connection, and the silicone does not have a strong ability to resist deformation, so it will not affect the vibration deformation of the driving assembly composed of the piezoelectric sheet 11 and the connecting sheet 12.

[0055] Reference Figure 1 to Figure 3bAs shown, in one embodiment, the mass member 13 is a layered structure; or, the mass member 13 includes a plurality of mass blocks arranged at intervals.

[0056] In this specific example, the mass member 13 provides mass for the entire sound-generating device, thereby reducing the initial resonance frequency; the thickness of the mass member 13 may be, for example, 0.3 mm, and its density is 3000 [kg / m 3 The mass member 13 may be made of a soft and high-density polymer material, such as fluororubber. The mass member 13 may be a single layered structure or may be composed of a plurality of mass blocks arranged at intervals to meet different sound generation requirements.

[0057] According to another embodiment of the present application, an electronic device is provided, and the electronic device includes the sound-generating device 1 as described above.

[0058] The above embodiments focus on the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Considering the simplicity of the text, they will not be repeated here.

[0059] Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are only for illustration, not for limiting the scope of the present application. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A sound-generating device, characterized in that: The sound-generating device comprises: A piezoelectric sheet (11), wherein a cross section of the piezoelectric sheet (11) perpendicular to the thickness direction comprises a first side (111), a second side (112), a third side (113) and a fourth side (114); wherein the first side (111) and the second side (112) are arranged opposite to each other along a first direction, and the first side (111) and the second side (112) are arc-shaped; the third side (113) and the fourth side (114) are arranged opposite to each other along a second direction, and the third side (113) and the fourth side (114) are straight-line-shaped; the piezoelectric sheet (11) has a first surface arranged along its thickness direction; A connecting sheet (12), the connecting sheet (12) being laminated and connected to the first surface of the piezoelectric sheet (11); A mass member (13), the mass member (13) being located on a side of the connecting sheet (12) away from the piezoelectric sheet (11), and the mass member (13) and the connecting sheet (12) being flexibly connected.

2. The sound generating device according to claim 1, characterized in that: The first side (111) and the second side (112) are arc-shaped with equal radius, and the third side (113) and the fourth side (114) are straight lines with equal length; the diameter of the first side (111) is greater than the length of the third side (113).

3. The sound generating device according to claim 1, characterized in that: The ratio of the thickness of the piezoelectric sheet (11) to the thickness of the connecting sheet (12) is 2:

1.

4. The sound generating device according to claim 1, characterized in that: The connecting piece (12) is made of a polymer material or a light foam metal.

5. The sound generating device according to claim 1, characterized in that: Along the thickness direction of the piezoelectric sheet (11), the projection of the piezoelectric sheet (11) is located within the projection range of the connecting sheet (12).

6. The sound generating device according to claim 5, characterized in that: The connecting piece (12) is circular, and the central axis of the connecting piece (12) coincides with the central axis of the piezoelectric piece (11).

7. The sound generating device according to claim 6, characterized in that: The radius of the connecting piece (12) is at least 1 mm greater than the radius of the first side edge (111).

8. The sound generating device according to claim 1, characterized in that: The sound-generating device further comprises a foam layer (14), wherein the foam layer (14) is arranged between the mass member (13) and the connecting sheet (12).

9. The sound generating device according to claim 8, characterized in that: The thickness of the foam layer (14) is greater than or equal to 0.1 mm.

10. The sound generating device according to claim 1, characterized in that: The mass member (13) is a layered structure; or, the mass member (13) comprises a plurality of mass blocks arranged at intervals.

11. An electronic device, characterized in that: The electronic device comprises a sound emitting device (1) as claimed in any one of claims 1 to 10.

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