Sound generator and sound generating device

Abstract

A sound generator includes: a piezoelectric device; a first counterweight member disposed at a first portion of the piezoelectric device; a second counterweight member disposed at a second portion of the piezoelectric device; a first elastic member disposed at a third portion between the first portion and the second portion of the piezoelectric device; and a protective member configured to cover the piezoelectric device, the first counterweight member, the second counterweight member, and the first elastic member.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to Japanese Patent Application No. 2021 - 000737, filed on January 6, 2021, the entire content of which is incorporated herein by reference. Technical field

[0003] The present disclosure relates to a sound generator and a sound - generating device. Background art

[0004] Recently, display devices with improved acoustic performance for enhancing realism have been developed, and technologies for enabling a display panel to function as a speaker have been developed.

[0005] As an example of related art, Korean Patent Publication No. 10 - 2018 - 0077582 discloses a display device including a display panel and an actuator. The display device of Korean Patent Publication No. 10 - 2018 - 0077582 may be referred to as a display - enabled sound - generating device, which controls the actuator to vibrate the display panel to emit sound. Summary of the invention

[0006] Accordingly, embodiments of the present disclosure are directed to providing a sound generator and a sound - generating device that substantially eliminate one or more problems caused by the limitations and disadvantages of the related art.

[0007] However, the related art needs to improve sound quality.

[0008] One aspect of the present disclosure is directed to providing a sound generator and a sound - generating device having enhanced sound quality.

[0009] Additional advantages and features of the present disclosure will be set forth in part in the following description, and in part will become apparent to those of ordinary skill in the art upon examination of the following, or may be learned from practice of the present disclosure. The objectives and other advantages of the present disclosure may be realized and attained by the structures particularly pointed out in the written description and claims hereof as well as the drawings.

[0010] To achieve these and other aspects of the inventive concept as embodied and broadly described, a sound generator includes: a piezoelectric device; a first weight member disposed at a first portion of the piezoelectric device; a second weight member disposed at a second portion of the piezoelectric device; a first elastic member disposed at a third portion between the first portion and the second portion of the piezoelectric device; and a protective member configured to cover the piezoelectric device, the first weight member, the second weight member, and the first elastic member.

[0011] In another aspect of the present disclosure, a sound generating device includes: a sound generator including a piezoelectric device; and an outer frame configured to cover the sound generator, the outer frame including an opening portion and a plurality of first vibration plates, and the sound generator is disposed at the opening portion.

[0012] According to an embodiment of the present disclosure, a sound generator and a sound generating device with enhanced sound quality can be provided.

[0013] It should be understood that the foregoing general description and the following detailed description of the present disclosure are both exemplary and explanatory, and are intended to provide further explanation of the inventive concept claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this application, showing embodiments of the present disclosure, and together with the description are used to explain the principles of the present disclosure.

[0015] Figure 1 is a diagram schematically showing a display device according to the prior art.

[0016] Figure 2 is a plan view schematically showing a schematic configuration of a piezoelectric device according to the prior art.

[0017] Figure 3 is along Figure 2 the cross-sectional view taken along line A-A' shown in

[0018] Figure 4 is a cross-sectional view showing in more detail the structure of a piezoelectric device according to the prior art.

[0019] Figure 5 is a schematic diagram showing the deformation that contracts in the horizontal direction when a voltage is applied to a piezoelectric device according to the prior art.

[0020] Figure 6 is a schematic diagram showing the deformation that extends in the horizontal direction when a voltage is applied to a piezoelectric device according to the prior art.

[0021] Figure 7 is a cross-sectional view showing the configuration of a piezoelectric device according to a comparative example.

[0022] Figure 8 is a schematic diagram showing a vibration model according to a comparative example.

[0023] Figure 9 is a schematic diagram showing a vibration model according to the prior art.

[0024] Figure 10 shows the structure of the sound generator 100 according to an embodiment of the present disclosure.

[0025] Figure 11 is a cross-sectional view taken along Figure 10 the line A-A' shown in

[0026] Figure 12 is a cross-sectional view taken along Figure 10 the line B-B' shown in

[0027] Figure 13 shows the internal structure of a sound generating device provided with a sound generator according to an embodiment of the present disclosure.

[0028] Figure 14 is a cross-sectional view taken along Figure 13 the line A-A' shown in

[0029] Figure 15 is a cross-sectional view taken along Figure 13 the line B-B' shown in

[0030] Figure 16 shows the internal structure of a sound generating device provided with a sound generator according to a comparative example.

[0031] Figure 17 is a characteristic diagram showing the results obtained by comparing Figure 13 the sound characteristics of the sound generating device shown in Figure 16 with the sound characteristics of the sound generating device shown in

[0032] Figure 18 shows the internal structure of a sound generating device according to a first modified embodiment provided with a sound generator according to an embodiment of the present disclosure.

[0033] Figure 19 shows the internal structure of a sound generating device according to a second modified embodiment provided with a sound generator according to an embodiment of the present disclosure.

[0034] Figure 20 shows the internal structure of a sound generating device according to a third modified embodiment provided with a sound generator according to an embodiment of the present disclosure.

[0035] Figure 21 shows the internal structure of a sound generating device according to a fourth modified embodiment provided with a sound generator according to an embodiment of the present disclosure.

[0036] Figure 22 shows the internal structure of a sound generating device according to a fifth modified embodiment provided with a sound generator according to an embodiment of the present disclosure.

[0037] Figure 23 shows the internal structure of a sound generating device according to a sixth modified embodiment provided with a sound generator according to an embodiment of the present disclosure.

[0038] Figure 24 The internal structure of a sound generating device according to a seventh modified embodiment provided with a sound generator according to an embodiment of the present disclosure is shown.

[0039] Figure 25 The internal structure of a sound generating device according to an eighth modified embodiment provided with a sound generator according to an embodiment of the present disclosure is shown.

[0040] Figure 26 The internal structure of a sound generating device according to a ninth modified embodiment provided with a sound generator according to an embodiment of the present disclosure is shown.

[0041] Throughout the drawings and the detailed description, unless otherwise noted, the same reference numerals should be understood to refer to the same elements, features, and structures. For clarity, illustration, and convenience, the relative sizes and depictions of these elements may be exaggerated. Detailed Description of the Embodiment

[0042] Now, embodiments of the present disclosure will be described in detail, and examples of the embodiments are shown in the drawings. In the following description, when a detailed description of well-known functions or configurations related to this document is determined to unnecessarily obscure the gist of the inventive concept, the detailed description thereof will be omitted. The progress of the described processing steps and / or operations is an example; however, except for steps and / or operations that must occur in a specific order, the order of the steps and / or operations is not limited to that set forth herein and may be changed as known in the art. The same reference numerals always denote the same elements. The names of the respective elements used in the following description are only selected for ease of writing the specification and may therefore be different from those used in actual products.

[0043] The advantages and features of the present disclosure and the method of achieving them will be clarified by the embodiments described below in conjunction with the drawings. However, the present disclosure may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art. In addition, the present disclosure is only defined by the scope of the claims.

[0044] The shapes, sizes, ratios, angles, and quantities disclosed in the drawings for describing the embodiments of the present disclosure are merely examples, and thus, the present disclosure is not limited to the illustrated details. Throughout the specification, like reference numerals denote like elements. In the following description, when it is determined that a detailed description of a related well-known function or configuration unnecessarily obscures the gist of the present disclosure, the detailed description thereof will be omitted. In cases where "comprising", "having", and "including" described in the present disclosure are used, another component may be added unless "only~" is used. Singular terms may include plural forms unless the contrary is mentioned.

[0045] When explaining an element, although not explicitly described, the element is construed as including an error or tolerance range.

[0046] When describing a positional relationship, for example, when the positional relationship between two parts is described as "on", "above", "below", and "next to", one or more other parts may be provided between the two parts, unless more restrictive terms such as "only" or "directly" are used.

[0047] When describing a temporal relationship, for example, when the chronological order is described as "after", "subsequently", "next", and "before", discontinuous cases may be included, unless more restrictive terms such as "only" or "directly" are used.

[0048] In the description of the embodiments, when a structure is described as being "on or above" or "under" or "below" another structure, such description shall be construed to include cases where these structures are in contact with each other and cases where a third structure is provided therebetween.

[0049] It should be understood that although terms such as "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of the present disclosure, the first element may be referred to as the second element, and similarly, the second element may be referred to as the first element.

[0050] When describing the elements of the present disclosure, terms such as "first", "second", "A", "B", "(a)", "(b)", etc. may be used. These terms are only used to distinguish the corresponding elements from other elements, and the nature, order, or quantity of the corresponding elements are not limited by these terms. When an element is stated to be "connected", "coupled", or "adhered" to another element or layer, unless otherwise specified, the element or layer may not only be directly connected or adhered to another element or layer, but also be indirectly connected or adhered to another element or layer when one or more intermediate elements or layers are "provided" or "interposed" between the element or layer.

[0051] The term "at least one" should be understood to include any and all combinations of one or more of the associated listed items. For example, the meaning of "at least one of the first item, the second item, and the third item" means all items selected from two or more of the first item, the second item, and the third item, as well as combinations of the first item, the second item, or the third item.

[0052] The size and thickness of each component shown in the drawings are shown for convenience of description, and the present disclosure is not limited to the size and thickness of the components shown.

[0053] The features of various embodiments of the present disclosure can be partially or wholly coupled or combined with each other and can interoperate and be technically driven differently from each other as can be fully understood by those skilled in the art. Embodiments of the present disclosure can be executed independently of each other or can be executed together in a mutually dependent manner.

[0054] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals refer to the same elements having the same functions, and repeated descriptions will be omitted or given briefly. For ease of description, the scale of each element shown in the drawings is different from the actual scale and thus is not limited to the scale shown in the drawings.

[0055] [Prior Art]

[0056] Figure 1 FIG. 1 schematically shows a display device 1 according to the prior art.

[0057] The display device 1 may be an electronic poster, a digital billboard, an electronic billboard, a computer image output device, a television, a smartphone, a game console, or the like, but embodiments of the present disclosure are not limited thereto.

[0058] As Figure 1 shown, the display device 1 may include a piezoelectric device 10, a display panel 20, an elastic member 30, a first controller 40, a second controller 50, a data driving circuit 60, and a gate driving circuit 70. The display device 1 may be a device that displays an image through the display panel 20 based on input RGB data or the like and generates sound or vibration based on an input sound signal (or vibration driving signal) or the like. Therefore, the display device 1 may be implemented as a sound generating device.

[0059] The display panel 20 may include a plurality of pixels P arranged in a matrix. The pixel P may include a light emitting device, which includes an organic light emitting diode or the like. When the display device 1 is capable of displaying a color image, the pixel P may be a sub-pixel that displays one of a plurality of colors (e.g., RGB) for realizing the color image.

[0060] The piezoelectric device 10 may be an element that is displaced due to the inverse piezoelectric effect when a voltage is applied based on an input sound signal. The piezoelectric device 10 may be an element that is bent and displaced due to a voltage (e.g., a bimorph or a unimorph). Since the input sound signal is an alternating current (AC) voltage, the piezoelectric device 10 may be used as a vibration device that vibrates according to the input sound signal.

[0061] The elastic member 30 can be a member made of an elastic material. The material of the elastic member 30 can have a lower elastic modulus than the piezoelectric device 10 and the display panel 20, and can be a material such as rubber. A part of the piezoelectric device 10 can be coupled or connected to a part of the display panel 20 through the elastic member 30. Therefore, the vibration of the piezoelectric device 10 can be transmitted to the display panel 20, and the display panel 20 can emit sound based on the sound signal input to the piezoelectric device 10.

[0062] The host system 2 can be a system including one device or multiple devices that provide an image signal such as RGB data, a sound signal, and a timing signal to control the display device 1. The timing signal can include a vertical synchronization signal, a horizontal synchronization signal, a data enable signal, etc. The host system 2 can be, for example, a sound source playback device, a local broadcast device, a radio broadcast playback system, a television (TV) system, a set-top box, a navigation system, a disc player, a computer, a home theater system, and a video phone system, etc. In addition, the display device 1 and the host system 2 can be an integrated device, or can be configured as separate devices.

[0063] The first controller 40 can provide a voltage to the piezoelectric device 10 based on the sound signal and the timing signal input from the host system 2. The second controller 50 can control the data driving circuit 60 and the gate driving circuit 70 based on the image data and the timing signal input from the host system 2. The data driving circuit 60 can provide a data voltage, etc. to the plurality of pixels P through the driving lines 61 provided at each column of the plurality of pixels P. The gate driving circuit 70 can provide a control signal to the plurality of pixels P through the driving lines 71 provided at each row of the plurality of pixels P. In addition, each of the driving lines 61 and the driving lines 71 can be provided as multiple lines (or wirings).

[0064] Each of the first controller 40, the second controller 50, the data driving circuit 60, and the gate driving circuit 70 can be composed of one semiconductor IC or multiple semiconductor ICs. In addition, some or all of the first controller 40, the second controller 50, the data driving circuit 60, and the gate driving circuit 70 can be configured as one semiconductor IC or one body (or a single entity).

[0065] Figure 2 is a plan view showing a schematic configuration of the piezoelectric device 10 according to the prior art. Figure 3 is along Figure 2 the cross-sectional view taken along the line A-A' shown in. In Figure 2 the quadrilateral (or rectangular) boundary of the display panel 20 schematically shows the outer frame or the appearance or the shape of the display panel 20.

[0066] Figure 3One main surface of the display panel 20 shown in the figure can be an image display surface (or the first surface or the front surface) 20a, and the other main surface can be a rear surface (or the second surface or the back surface) 20b. In Figure 2 and Figure 3 In the coordinate axes shown, the horizontal direction parallel to the image display surface 20a is the x-axis direction, the vertical direction parallel to the image display surface 20a is the z-axis direction, and the depth direction parallel to the image display surface 20a is the y-axis direction.

[0067] In a plan view, the shape of the piezoelectric device 10 can be a rectangular shape having a long side direction ( Figure 2 and Figure 3 the z direction in Figure 2 and Figure 3 the x direction in

[0068] and a short side direction), and the shape of the piezoelectric device 10 can be a flat plate shape. Therefore, deformation that bends along the cross-section (line A-A') in the long side direction can occur. The long side direction of the piezoelectric device 10 can be set perpendicular to the end of the display panel 20.

[0069] Figure 3 The piezoelectric device 10 shown in

[0070] can include a main surface (or the first surface) 10a and a second main surface (or the second surface) 10b. The elastic member 30 can connect (or couple) the first surface 10a of the piezoelectric device 10 to the rear surface 20b of the display panel 20. As described above, the piezoelectric device 10 and the elastic member 30 can be provided at the rear surface 20b of the display panel 20 so as not to interfere with the image display on the image display surface 20a.

[0071] Figure 4 is a cross-sectional view showing in more detail the structure of the piezoelectric device 10 according to the prior art. Similar to Figure 3 , Figure 4 is a cross-sectional view taken along the line A-A' shown in Figure 2 ,but its direction is Figure 3 rotated 90 degrees to the right. In addition,Figure 4 The connection relationship between electrodes included in the piezoelectric device 10 is schematically shown through a circuit diagram for describing a method of inputting a sound signal to the piezoelectric device 10.

[0072] Figure 4 The piezoelectric device 10 shown in [the figure] may include a bimorph structure in which two piezoelectric layers are laminated. Figure 4 The piezoelectric device 10 shown in [the figure] may include a first electrode 11, a first piezoelectric layer 12, a second electrode 13, a second piezoelectric layer 14, and a third electrode 15. The first electrode 11 may be arranged closest to the display panel 20 and may be connected to the elastic member 30. The third electrode 15 may be arranged farthest from the display panel 20. The second electrode 13 may be arranged between the first electrode 11 and the third electrode 15.

[0073] The first piezoelectric layer 12 may be supported between the first electrode 11 and the second electrode 13. The second piezoelectric layer 14 may be supported between the second electrode 13 and the third electrode 15. The arrows shown in the first piezoelectric layer 12 and the second piezoelectric layer 14 represent the polarization directions, and the polarization direction of the first piezoelectric layer 12 may be the same as the polarization direction of the second piezoelectric layer 14.

[0074] In addition, lines (or wirings) for applying voltage to each electrode may be connected to the first electrode 11, the second electrode 13, and the third electrode 15, but in Figure 4 [the figure], the illustration of the connection lines is omitted. Additionally, the lines may be connected by soldering or the like, and the embodiments of the present disclosure are not limited to a specific method.

[0075] The voltage applied to the piezoelectric device 10 may be based on the sound signal. Therefore, the voltage applied to the piezoelectric device 10 may be an AC voltage corresponding to the frequency of the sound to be generated. In Figure 4 [the figure], the AC voltage is represented by the circuit symbol of an AC power supply. In the AC power supply V, one terminal (or the first terminal) may be connected to the first electrode 11 and the third electrode 15, and the other terminal (or the second terminal) may be connected to the second electrode 13. For example, the voltage applied to the first electrode 11 and the voltage applied to the third electrode 15 may be in phase (or in-phase), the voltage applied to the first electrode 11 and the voltage applied to the second electrode 13 may be out of phase (or out-of-phase), and the voltage applied to the second electrode 13 and the voltage applied to the third electrode 15 may be in phase (or in-phase). Therefore, the voltage applied to the first piezoelectric layer 12 and the voltage applied to the second piezoelectric layer 14 may be out of phase (or out-of-phase).

[0076] The materials of the first piezoelectric layer 12 and the second piezoelectric layer 14 may be piezoelectric materials, and the embodiments of the present disclosure are not limited to specific materials. For example, the first piezoelectric layer 12 and the second piezoelectric layer 14 may include lead zirconate titanate (PZT), etc. PZT has high piezoelectricity, and thus, may have a large displacement amount relative to the applied voltage. In addition, although not shown in Figure 4 , the periphery (or outer edge) of the piezoelectric device 10 may be covered with an insulator such as resin to prevent an electrical short circuit between the piezoelectric device 10 and another member.

[0077] Figure 5 FIG. is a schematic view showing a deformation in which the piezoelectric device 10 according to the prior art contracts in the horizontal direction when a voltage is applied. Figure 6 FIG. is a schematic view showing a deformation in which the piezoelectric device 10 according to the prior art expands in the horizontal direction when a voltage is applied. As Figure 4 shown, the polarization direction of the first piezoelectric layer 12 may be the same as the polarization direction of the second piezoelectric layer 12. The direction of the voltage applied to the first piezoelectric layer 12 may be opposite to the direction of the voltage applied to the second piezoelectric layer 14. For example, the voltages applied to the first piezoelectric layer 12 and the second piezoelectric layer 14 may have opposite phases. Therefore, the stretching direction of the first piezoelectric layer 12 may be opposite or reverse (or inverse) to the stretching direction of the second piezoelectric layer 14.

[0078] As Figure 5 shown, when the first piezoelectric layer 12 deforms and contracts in the horizontal direction, the second piezoelectric layer 14 may deform in the direction in which it expands in the horizontal direction. Therefore, the end of the piezoelectric device 10 may bend in the direction approaching the display panel 20. For example, the display panel 20 may deform based on the stress applied toward the piezoelectric device 10.

[0079] As Figure 6 shown, when the first piezoelectric layer 12 deforms and expands in the horizontal direction, the second piezoelectric layer 14 may deform in the direction in which it contracts in the horizontal direction. Therefore, the end of the piezoelectric device 10 may bend in the direction away from the display panel 20. For example, the display panel 20 may deform based on the stress applied in the direction away from the piezoelectric device 10.

[0080] When an AC voltage based on an audio signal is applied to the piezoelectric device 10, Figure 5 the shape (or form) shown in Figure 6 and the shape (or form) shown in

[0081] may be alternately repeated at the frequency of the sound. Therefore, the vibration of the piezoelectric device 10 may be transmitted to the display panel 20 to vibrate the display panel 20. Therefore, the display panel 20 may be used as a speaker such that the display panel 20 emits sound based on the audio signal.In the prior art, the effects obtained when a part of the piezoelectric device 10 is connected to the display panel 20 through the elastic member 30 will be described. Figure 7 is a cross-sectional view showing the configuration of the piezoelectric device 10 according to the comparative example. Figure 8 is a schematic diagram showing the vibration model according to the comparative example.

[0082] In Figure 7 In the comparative example shown, the entire surface of the piezoelectric device 10 can be directly connected to the display panel 20. Based on such a configuration, the displacement of the piezoelectric device 10 can be transmitted to the display panel 20. Therefore, the display panel 20 can be used as a speaker. According to Figure 8 the vibration model of the comparative example shown, a plurality of springs S1 and S2 can be connected to both ends of the mass points representing the piezoelectric device 10 and the display panel 20. The piezoelectric device 10 having a mass m1 can be directly connected to the display panel 20 having a mass m2.

[0083] The spring S1 having a spring constant k1 can be connected to the piezoelectric device 10, and the spring S2 having a spring constant k2 can be connected to the display panel 20. The spring S1 can be realized by simulating the elasticity of the piezoelectric device 10. The spring S2 can be realized by simulating the elasticity of the display panel 20 or the elasticity of the members (such as the housing, etc.) that constrain the display panel 20. In addition, in the vibration model, both ends thereof can be fixed ends or fixed members.

[0084] In the vibration model of the comparative example, the piezoelectric device 10 and the display panel 20 can be replaced by a single mass point having a mass m1 + m2. When a voltage is applied to the piezoelectric device 10, the force generated by the piezoelectric device 10 can vibrate the entire display panel 20 and the piezoelectric device 10 having a mass m1 + m2. For example, the mass m1 + m2 can be much larger than the mass m1. The force generated by the piezoelectric device 10 can affect an object having a very large mass. Therefore, the acceleration applied to the piezoelectric device 10 and the first vibration member 20 by this force may be small. Therefore, the displacement amount of the piezoelectric device 10 and the display panel 20 may be smaller, and in the configuration of the comparative example, it may be difficult to increase the sound pressure of the sound generated from the display panel 20.

[0085] Figure 9 is a schematic diagram showing the vibration model according to the prior art. In Figure 9 the vibration model according to the prior art shown, a spring S3 having a spring constant k3 is connected between the mass points representing the display panel 20 and the piezoelectric device 10. The spring S3 can be realized by simulating the elasticity of the elastic member 30. The piezoelectric device 10 having a mass m1 is connected to the display panel 20 having a mass m2 through the spring S3.

[0086] In the vibration model according to the prior art, the piezoelectric device 10 and the display panel 20 are connected to each other by the elastic member 30. The force generated when a voltage is applied to the piezoelectric device 10 causes the piezoelectric device 10 having a mass m1 to vibrate. For example, the mass of the object to which the force is applied can be smaller than that of the comparative example, and thus, the acceleration applied to the piezoelectric device 10 by the force can be greater than that of the comparative example. Therefore, the piezoelectric device 10 can be in a resonant state with a large displacement. In addition, the displacement of the piezoelectric device 10 can be gradually transmitted to the display panel 20 through the spring S3, and thus, as in the comparative example, it may be difficult to suppress the displacement by the mass of the display panel 20. Therefore, in the embodiment of the prior art, compared with the comparative example, the displacement can be increased, and thus, the sound pressure level can be increased.

[0087] As described above, according to the prior art, when the display panel 20 is used as a speaker, the sound pressure level of the sound generated by the display panel 20 can be increased.

[0088] In addition, in the prior art, the vibration source is the piezoelectric device 10, and the sound source is the display panel 20 having a large mass and a low natural frequency. Therefore, in the prior art, compared with the configuration in which the piezoelectric device 10 directly generates sound or the configuration in which sound is generated by a member connecting the piezoelectric device 10 to a separate small vibration plate different from the display panel 20 and having a high natural frequency, the sound pressure level in the low audio frequency band can be further increased.

[0089] As described above, according to the prior art, the sound pressure level in the low audio frequency band can be increased, but it may be necessary to increase the sound pressure level in each of the middle audio frequency band and the high audio frequency band. In the embodiment of the present disclosure, as described below, the noise, high-frequency sound, and the sound pressure level difference between different audio frequency bands can be controlled. In addition, in the following description, the low audio frequency band may be defined as sound having a frequency of 300 Hz or less, the middle audio frequency band may be defined as sound having a frequency higher than 300 Hz and 1 kHz or less, and the high audio frequency band may be defined as sound having a frequency higher than 1 kHz, but is not limited thereto.

[0090] Figure 10 The structure of the sound generator 100 according to an embodiment of the present disclosure is shown. Figure 11 is a cross-sectional view taken along Figure 10 the line A-A' shown in Figure 12 is a cross-sectional view taken along Figure 10 the line B-B' shown in

[0091] Refer to Figures 10 to 12, the sound generator 100 may include a first counterweight member 101, a first elastic member 102, a second counterweight member 103, a second elastic member 104, a piezoelectric device 105 having a rectangular shape, and a protection member 106. For example, the first counterweight member 101 and the second counterweight member 103 may each be a balance weight, a mass block, a mass member, or a vibration amplification member, but the embodiments of the present disclosure are not limited thereto. The protection member 106 may be an elastic protection member or a flexible protection member, but the embodiments of the present disclosure are not limited thereto.

[0092] The piezoelectric device 105 may have a rectangular shape including a long side and a short side. For example, with respect to the long side direction, the piezoelectric device 105 may include a first portion (or a second vibration region or a second sound generation region), a second portion (or a first vibration region or a first sound generation region), and a third portion (or a third vibration region or a third sound generation region) between the first portion and the second portion, and the first portion to the third portion may generate sounds in different audio segments respectively.

[0093] The first counterweight member 101 may be a member disposed at the first portion of the piezoelectric device 105 along the long side direction and configured to amplify the vibration of the piezoelectric device 105. The second counterweight member 103 may be a member disposed at the second portion of the piezoelectric device 105 along the long side direction and configured to amplify the vibration of the piezoelectric device 105. The first elastic member 102 may include an elastic material and may include a material that is more difficult to deform than the second elastic member 104. For example, it may be an aggregated element in which the material of the protection member 106 is hardened. The second elastic member 104 may include an elastic material that is more easily deformable than the first elastic member 102 or may include an elastic material having a density lower than that of the first elastic member 102, and may be, for example, a sponge.

[0094] The piezoelectric device 105 may correspond to the piezoelectric device 10 according to the prior art and may be a device that can be displaced by the inverse piezoelectric effect when a voltage based on an input sound signal is applied to generate sound in the sound generator 100.

[0095] The protective member 106 may be an elastic member that covers the first weight member 101, the first elastic member 102, the second weight member 103, and the piezoelectric device 105 in the sound generator 100, and for example, may include silicone, rubber, silicone rubber, etc., but the embodiments of the present disclosure are not limited thereto. The protective member 106 may be a housing including, for example, silicone rubber, and may include a notch (or slit) provided at a part thereof. The protective member 106 may cover or surround each of the first weight member 101, the first elastic member 102, the second weight member 103, and the piezoelectric device 105 inserted therein through the notch. For example, the first weight member 101, the first elastic member 102, the second weight member 103, and the piezoelectric device 105 may be provided as one body (or a single body) and may be inserted into the housing (or the protective member 106) through the notch, and thus, may cover or integrally surround each of the first weight member 101, the first elastic member 102, the second weight member 103, and the piezoelectric device 105.

[0096] A first portion provided with the first weight member 101 in the longitudinal direction of the piezoelectric device 105 may be a high audio frequency band generating portion that generates sound having a high frequency (or a first frequency band). A second portion provided with the second weight member 103 in the longitudinal direction of the piezoelectric device 105 may be a low audio frequency band generating portion that generates sound having a low frequency (or a second frequency band). A portion provided with the first elastic member 102 may be a middle audio frequency band generating portion that generates sound having a middle frequency (or a third frequency band) between the sound generated by the high audio frequency band generating portion and the sound generated by the low audio frequency band generating portion. In addition, the second elastic member 104 may be provided at the low audio frequency band generating portion, but the embodiments of the present disclosure are not limited thereto. In addition, as Figure 10 shown, in the sound generator 100, the low audio frequency band generating portion may have a relatively larger size (or area) than each of the high audio frequency band generating portion and the middle audio frequency band generating portion.

[0097] Figure 13 The internal structure of the sound generating device 200 provided with the sound generator 100 according to an embodiment of the present disclosure is shown. Figure 14 is a cross-sectional view taken along the line A-A' shown in Figure 13 . Figure 15 is a cross-sectional view taken along the line B-B' shown in Figure 13 .

[0098] Refer to Figure 10 and Figures 13 to 15, according to an embodiment of the present disclosure, the sound generating device 200 may include a sound generator 100. The sound generator 100 includes a piezoelectric device, an elastic member 201, an outer frame (or first frame) 203 including an opening 202, and an inner frame (or second frame) 204. The sound generating device 200 may be supported between two diaphragm plates 203a.

[0099] The mid - audio - frequency - band generating portion of the sound generator 100 may be connected or fixed to the two diaphragm plates 203a through a first elastic member 102 at a position closer to the first portion (the first portion is the portion where the first weight member 101 is provided) in the long - side direction of the piezoelectric device 105 than the center in the long - side direction of the piezoelectric device 105. The elastic member 201 may include an elastic material. For example, it may be the same sponge as the second elastic member 104. The elastic member 201 may be arranged to contact the outer frame 203.

[0100] The outer frame 203 may output the sound generated by the sound generator 100 to the outside. The outer frame 203 may include a high - audio - frequency - band generating portion (or first portion) for generating a high - audio - frequency band, a low - audio - frequency - band generating portion (or second portion) for generating a low - audio - frequency band, and a mid - audio - frequency - band generating portion (or third portion) for generating a mid - audio - frequency band between the high - audio - frequency - band generating portion (or first portion) and the low - audio - frequency - band generating portion (or second portion).

[0101] In addition, the two diaphragm plates 203a may be included in the outer frame 203, or may be provided in two or more. The sound generator 100 may be provided at least at one of the opening 202 provided at the first portion of the outer frame 203 and the third portion of the outer frame 203. The outer frame 203 having the opening 202 and the inner frame 204 may be provided as an integral body (or a single main body), but the embodiments of the present disclosure are not limited thereto.

[0102] The inner frame 204 may be configured such that each of the sound generated by the mid - audio - frequency - band generating portion and the sound generated by the low - audio - frequency - band generating portion is introduced into a space formed in a part of the interior of the sound generating device 200 and reverberates.

[0103] In the sound generator 100, the first elastic member 102 may be attached to the diaphragm plate of the outer frame 203 at an adhesion surface 1020 provided inside the mid - audio - frequency - band generating portion (or third portion), and may be attached to the diaphragm plate of the outer frame 203 at an adhesion surface 1040 provided inside the low - audio - frequency - band generating portion (or second portion). A part (or third portion) of the diaphragm plate 203a of the adhesion surface 1020 may be the first diaphragm plate, and a part (or second portion) of the diaphragm plate 203a of the adhesion surface 1040 may be the second diaphragm plate. Therefore, the diaphragm plate 203a may be composed of multiple diaphragm plates.

[0104] Figure 16 The internal structure of the sound generating device 200a provided with the sound generator 100a according to the comparative example is shown. The sound generating device 200a may include a sound generator 100a, and the sound generator 100a includes a piezoelectric device, an elastic member 201, and an outer frame 203. The sound generator 100a may include two second weight members 103, two second elastic members 104, and a piezoelectric device 105. In the sound generator 100a, the two second weight members 103 and the two second elastic members 104 may be provided at two portions (a first portion and a second portion) in the long side direction of the piezoelectric device 105.

[0105] Figure 17 is shown by comparison Figure 13 the sound characteristics of the sound generating device 200 shown in Figure 16 and the sound characteristics of the sound generating device 200a shown in Figure 17 is a characteristic diagram of the obtained results. In Figure 17 , the horizontal axis represents frequency and the vertical axis represents amplitude. In the characteristic diagram of Figure 17 , the first enlarged view, the second enlarged view, and the third enlarged view show the enlargement of three portions. In the first enlarged view, the second enlarged view, and the third enlarged view, the characteristics of the mid-audio frequency band or the high-audio frequency band are shown, but in all the enlarged views, the sound pressure level increases (in particular, the sound pressure level in the high-audio frequency band increases) and the sound pressure level difference between the mid-audio frequency band and the high-audio frequency band decreases. In addition, in the second enlarged view and the third enlarged view, it can be seen that as the change amplitude of the frequency in the high-audio frequency band increases or decreases, the high-frequency sound decreases and the noise in the high-audio frequency band decreases. As Figure 17 shown, in the sound generating device 200 shown in Figure 13 , the noise in the high-audio frequency band decreases, and the sound pressure level difference between the mid-audio frequency band and the high-audio frequency band can decrease.

[0106] In addition, the sound generating device according to the embodiment of the present disclosure is not limited to Figures 13 to 15 the configuration (or structure) shown in

[0107] Figure 18 The internal structure of the sound generating device 200a according to the first modified embodiment provided with the sound generator 100 according to the embodiment of the present disclosure is shown.

[0108] Refer to Figure 18, the sound generating device 200a according to the first modified embodiment of the present disclosure may include a sound generator 100, and the sound generator 100 includes a piezoelectric device, an elastic member 201, an outer frame 203 including an opening 202, and a plurality of inner frames 204 and 204a. Compared with the sound generating device 200 according to the embodiment of the present disclosure, the sound generating device 200a according to the first modified embodiment of the present disclosure is different in that an inner frame 204a is additionally provided in the sound generating device 200, while other elements are the same. Therefore, the repeated description of the same elements is omitted.

[0109] Two inner frames 204a may be provided in the region of the low audio frequency band, and may be configured such that the path of the sound generated by the sound generator 100 becomes narrower in the direction away from the region of the middle audio frequency band and reverberates in the direction away from the region of the middle audio frequency band. According to Figure 18 the configuration shown, the sound pressure level characteristic of the low audio frequency band can be improved.

[0110] Figure 19 The internal structure of a sound generating device 200b according to a second modified embodiment provided with a sound generator 100 according to an embodiment of the present disclosure is shown.

[0111] Referring to Figure 19 , the sound generating device 200b according to the second modified embodiment of the present disclosure may include a sound generator 100, and the sound generator 100 includes a piezoelectric device, an elastic member 201, an outer frame 203 including an opening 202, and an inner frame 204b. Compared with the sound generating device 200 according to the embodiment of the present disclosure, the sound generating device 200b according to the second modified embodiment of the present disclosure is different in that the inner frame 204b is provided instead of the inner frame 204 of the sound generating device 200, while other elements are the same. Therefore, the repeated description of the same elements is omitted.

[0112] The inner frame 204b may be provided in the region of the middle and low audio frequency bands, and may be configured such that the path of the sound generated by the sound generator 100 bypasses the region of the middle and low audio frequency bands at least once and reverberates in the region of the middle audio frequency band. According to Figure 19 the configuration shown, the sound pressure level characteristic of the low audio frequency band can be improved.

[0113] Figure 20 The internal structure of a sound generating device 200c according to a third modified embodiment provided with a sound generator 100 according to an embodiment of the present disclosure is shown.

[0114] Referring to Figure 20, the sound generating device 200c according to the third modified embodiment of the present disclosure may include a sound generator 100. The sound generator 100 includes a piezoelectric device, an elastic member 201, an outer frame 203 including an opening 202 and a port 205, and an inner frame 204a. Compared with the sound generating device 200b according to the second modified embodiment of the present disclosure, the sound generating device 200c according to the third modified embodiment of the present disclosure is different in that a port 205 is provided at the outer frame 203, while other components are the same. Therefore, the repeated description of the same components is omitted.

[0115] The port 205 can be provided to increase the sound pressure level in the low audio frequency band. In a closed speaker, the rear surface (or back) of the speaker can be closed and a cavity can be provided. However, when a port (or hole) is formed at the closed cavity, the resonant frequency can be adjusted according to the capacity of the cavity, the cross-sectional area of the opening of the port 205, and the length of the pipe provided at the cavity of the port 205. Therefore, a speaker that emphasizes the low audio frequency band can be realized. Therefore, the port 205 can be configured at the outer frame 203 to communicate with the space (or cavity) surrounded by the outer frame 203 and the two vibrating plates 203a. For example, the opening shape of the port 205 is not limited to a specific shape and can be circular or elliptical, or can be quadrilateral or polygonal. The port 205 can be configured at the outer frame 203 in the region of the mid-low audio frequency band to increase the sound pressure level in the low audio frequency band. For example, the resonant frequency can be adjusted through the port 205, and thus, the sound pressure level in the low audio frequency band can be increased. In Figure 20 the configuration shown, the sound pressure level characteristics in the low audio frequency band can be improved.

[0116] Figure 21 The internal structure of a sound generating device 200d according to a fourth modified embodiment provided with a sound generator 100 according to an embodiment of the present disclosure is shown.

[0117] Referring to Figure 21 , the sound generating device 200d according to the fourth modified embodiment of the present disclosure may include a sound generator 100. The sound generator 100 includes a piezoelectric device, an elastic member 201, an outer frame 203 including an opening 202, and an inner frame 204c. Compared with the sound generating device 200 according to the embodiment of the present disclosure, the sound generating device 200d according to the fourth modified embodiment of the present disclosure is different in that the inner frame 204c is provided instead of the inner frame 204 of the sound generating device 200, while other components are the same. Therefore, the repeated description of the same components is omitted.

[0118] The inner frame 204c can be provided at each of the mid-audio frequency band region and the low-audio frequency band region, and can be configured such that the path of the sound generated by the sound generator 100 reverberates to the mid-audio frequency band region, and the sound path bypasses the low-audio frequency band region and reverberates at a region far from the mid-audio frequency band region. According toFigure 21 The configuration shown can increase the sound pressure level in the mid - audio range and the sound pressure level in the low - audio range.

[0119] Figure 22 The internal structure of a sound - generating device 200e according to a fifth modified embodiment provided with a sound generator 100 according to an embodiment of the present disclosure is shown.

[0120] Reference Figure 22 , a sound - generating device 200e according to a fifth modified embodiment of the present disclosure may include a sound generator 100. The sound generator 100 includes a piezoelectric device, an elastic member 201, an outer frame 203 including an opening 202 and a plurality of ports 205 and 205a, and an inner frame 204c. Compared with the sound - generating device 200d according to the fourth modified embodiment of the present disclosure, the sound - generating device 200e according to the fifth modified embodiment of the present disclosure is different in that ports 205 and 205a are provided at the outer frame 203, while other components are the same. Therefore, repeated descriptions of the same components are omitted.

[0121] The port 205 (or the first port) may be configured at the outer frame 203 in the region of the low - audio range to increase the sound pressure level in the low - audio range, and the port 205a (or the second port) may be configured at the outer frame 203 in the region of the mid - audio range to increase the sound pressure level in the mid - audio range. For example, the port 205 may be configured in the same way as the Figure 20 shown port 205. The port 205a may be configured in the same way as the port 205, except that the port 205a is provided at the outer frame 203 adjacent to the opening 202. According to the Figure 22 configuration shown, the sound pressure level in the mid - audio range and the sound pressure level in the low - audio range can be increased.

[0122] Figure 23 The internal structure of a sound - generating device 200f according to a sixth modified embodiment provided with a sound generator 100 according to an embodiment of the present disclosure is shown.

[0123] Reference Figure 23 , a sound - generating device 200f according to a sixth modified embodiment of the present disclosure may include a sound generator 100. The sound generator 100 includes a piezoelectric device, an elastic member 201, an outer frame 203 including an opening 202 and a port 205, and a plurality of inner frames 204 and 204d. Compared with the sound - generating device 200 according to the embodiment of the present disclosure, the sound - generating device 200f according to the sixth modified embodiment of the present disclosure is different only in that an inner frame 204d is added and a port is provided at the outer frame 203, while other components are the same. Therefore, repeated descriptions of the same components are omitted.

[0124] The inner frame 204d can be disposed in the region of the low audio frequency band, and can be disposed substantially parallel to the inner frame 204 disposed in the region of the low audio frequency band, and can be configured such that the path of the sound generated by the sound generator 100 bypasses the region of the low audio frequency band to face the corner of the outer frame 203 and reverberates in a region away from the mid-audio frequency band region. According to Figure 23 the configuration shown, the sound pressure level of the low audio frequency band can be increased.

[0125] Figure 24 FIG. shows the internal structure of a sound generating device 200g according to a seventh modified embodiment provided with a sound generator 100 according to an embodiment of the present disclosure.

[0126] Referring to Figure 24 , the sound generating device 200g according to the seventh modified embodiment of the present disclosure may include a sound generator 100, the sound generator 100 including a piezoelectric device, an elastic member 201, an outer frame 203 including an opening 202 and a port 205, and a plurality of inner frames 204, 204d, 204e, and 204f. Compared with the sound generating device 200f according to the sixth modified embodiment of the present disclosure, the sound generating device 200g according to the seventh modified embodiment of the present disclosure is different only in that inner frames 204e and 204f are additionally provided, while the other elements are the same. Therefore, the repeated description of the same elements is omitted.

[0127] The inner frame 204e can be disposed in the region of the low audio frequency band. A part of the inner frame 204e can be configured to block the path of the sound passing through the region between the inner frame 204 and the inner frame 204d, such that the path of the sound generated by the sound generator 100 bypasses and reverberates, and another part of the inner frame 204e can be configured to be substantially parallel to a part of the inner frame 204d disposed in the region of the low audio frequency band. The inner frame 204f can be disposed substantially parallel to the other part of the inner frame 204e, such that the path of the sound generated by the sound generator 100 bypasses and reverberates. The port 205 can be disposed at the outer frame 203 in the region of the low audio frequency band, thereby increasing the sound pressure level of the low audio frequency band. According to Figure 24 the configuration shown, the sound pressure level of the low audio frequency band can be increased.

[0128] Figure 25 FIG. shows the internal structure of a sound generating device 200h according to an eighth modified embodiment provided with a sound generator 100 according to an embodiment of the present disclosure.

[0129] Referring to Figure 25, the sound generating device 200h according to the eighth modified embodiment of the present disclosure may include a sound generator 100, and the sound generator 100 includes a piezoelectric device, an elastic member 201, an outer frame 203 including an opening 202, and an inner frame 204g. Compared with the sound generating device 200 according to the embodiment of the present disclosure, the sound generating device 200h according to the eighth modified embodiment of the present disclosure is different in that an inner frame 204g is provided instead of the inner frame 204 of the sound generating device 200, while other elements are the same. Therefore, the repeated description of the same elements is omitted.

[0130] The inner frame 204g may be provided in the region of the mid-audio band and may be configured such that the path of the sound generated by the sound generator 100 bypasses and reverberates along the outer frame 203. According to Figure 25 the configuration shown, the sound pressure level characteristics in the mid-audio band and the sound pressure level characteristics in the low-audio band can be improved.

[0131] Figure 26 The internal structure of a sound generating device 200i according to a ninth modified embodiment provided with a sound generator 100 according to an embodiment of the present disclosure is shown.

[0132] Referring to Figure 26 , the sound generating device 200i according to the ninth modified embodiment of the present disclosure may include a sound generator 100, and the sound generator 100 includes a piezoelectric device, an elastic member 201, an outer frame 203 including an opening 202 and a port 205a, and an inner frame 204g. Compared with the sound generating device 200h according to the eighth modified embodiment of the present disclosure, the sound generating device 200i according to the ninth modified embodiment of the present disclosure is different only in that a port 205a is provided at the outer frame 203 of the sound generating device 200h, while other elements are the same. Therefore, the repeated description of the same elements is omitted.

[0133] The port 205a may be configured to improve the sound pressure level characteristics in the mid-audio band and the sound pressure level characteristics in the low-audio band. For example, the port 205a may be provided at the outer frame 203 adjacent to the opening 203. According to Figure 26 the configuration shown, the sound pressure level characteristics in the mid-audio band and the sound pressure level characteristics in the low-audio band can be improved.

[0134] In addition, in Figures 18 to 26 the configuration shown, the sound pressure level of each audio band can be improved, and thus, the balance of each audio band can be adjusted. As described above, the embodiments and modified embodiments of the present disclosure can implement a sound generating device that can adjust noise, harmonic distortion sound, and the sound pressure level difference between different audio bands and can improve the sound quality.

[0135] The sound generator and the sound generating device according to the present disclosure will be described below.

[0136] A sound generator according to an embodiment of the present disclosure may include: a piezoelectric device; a high audio frequency band generating portion provided at one end in the long side direction of the piezoelectric device; a low audio frequency band generating portion provided at the other end in the long side direction of the piezoelectric device; a middle audio frequency band generating portion provided between the high audio frequency band generating portion and the low audio frequency band generating portion; a first weight member provided at the high audio frequency band generating portion; a second weight member provided at the low audio frequency band generating portion; a first elastic member provided at the middle audio frequency band generating portion; and a protective member covering the piezoelectric device, the first weight member, the second weight member, and the first elastic member.

[0137] According to some embodiments of the present disclosure, the sound generator may further include a second elastic member provided at the low audio frequency band generating portion.

[0138] According to some embodiments of the present disclosure, the low audio frequency band generating portion may be larger than each of the high audio frequency band generating portion and the middle audio frequency band generating portion.

[0139] A sound generating device according to an embodiment of the present disclosure may include: a sound generator including a piezoelectric device; and an outer frame covering the sound generator and including an opening portion and a plurality of first vibrating plates, and the sound generator may be provided at the opening portion.

[0140] According to some embodiments of the present disclosure, the outer frame may include a first portion generating a high audio frequency band, a second portion generating a low audio frequency band, and a third portion generating a middle audio frequency band between the first portion and the second portion.

[0141] According to some embodiments of the present disclosure, the opening portion may be provided at the first portion.

[0142] According to some embodiments of the present disclosure, the first vibrating plate may be provided at the third portion.

[0143] According to some embodiments of the present disclosure, the sound generator may be provided at the opening portion and the third portion.

[0144] According to some embodiments of the present disclosure, the outer frame may include a plurality of second vibrating plates and may be provided at the second portion.

[0145] The sound generating device according to an embodiment of the present disclosure may be a sound generating device including a sound generator that generates sound based on vibrations of a piezoelectric device having a rectangular shape. The sound generator includes: a high audio frequency band generating portion including a weight member disposed at one end in the long side direction of the piezoelectric device; a middle audio frequency band generating portion fixed to two vibration plates through a first elastic member at a position closer to one end in the long side direction of the piezoelectric device than the center in the long side direction of the piezoelectric device; a low audio frequency band generating portion including a weight member disposed at the other end in the long side direction of the piezoelectric device; and a protection member covering the piezoelectric device and covering the first elastic member or integrated with the first elastic member, and may be surrounded by an outer frame and two vibration plates.

[0146] According to some embodiments of the present disclosure, the low audio frequency band generating portion may be fixed to the two vibration plates through a second elastic member.

[0147] According to some embodiments of the present disclosure, an inner frame may be disposed in an area surrounded by the outer frame, and the inner frame may be configured such that at least one of the sound generated by the middle audio frequency band generating portion and the sound generated by the low audio frequency band generating portion is introduced into a space formed in a part of the space surrounded by the outer frame and the two vibration plates and reverberates.

[0148] The sound generator according to an embodiment of the present disclosure may include: a piezoelectric device; a first weight member disposed at a first portion of the piezoelectric device; a second weight member disposed at a second portion of the piezoelectric device; a first elastic member disposed at a third portion between the first portion and the second portion of the piezoelectric device; and a protection member configured to cover the piezoelectric device, the first weight member, the second weight member, and the first elastic member.

[0149] According to some embodiments of the present disclosure, the piezoelectric device may generate sounds in different audio frequency bands at the first portion to the third portion, respectively.

[0150] According to some embodiments of the present disclosure, the piezoelectric device may generate a high audio frequency band at the first portion, a low audio frequency band at the second portion, and may generate a middle audio frequency band between the high audio frequency band and the low audio frequency band at the third portion.

[0151] According to some embodiments of the present disclosure, the sound generator may further include a second elastic member disposed at the second portion of the piezoelectric device.

[0152] According to some embodiments of the present disclosure, the second elastic member may include an elastic material different from the material of the first elastic member.

[0153] According to some embodiments of the present disclosure, the second elastic member may include an elastic material having a density lower than that of the first elastic member.

[0154] According to some embodiments of the present disclosure, the size of the second portion may be greater than the size of each of the first portion and the third portion.

[0155] According to some embodiments of the present disclosure, the protection member may include an elastic material and integrally surround the piezoelectric device, the first weight member, the second weight member, and the first elastic member.

[0156] A sound generating device according to an embodiment of the present disclosure may include: a sound generator including a piezoelectric device; and an outer frame configured to cover the sound generator and configured to include an opening and a plurality of first vibration plates, and the sound generator may be disposed at the opening.

[0157] According to some embodiments of the present disclosure, the outer frame may include a first portion that generates a high audio frequency band, a second portion that generates a low audio frequency band, and a third portion that generates a mid audio frequency band between the first portion and the second portion.

[0158] According to some embodiments of the present disclosure, the opening may be disposed at the first portion.

[0159] According to some embodiments of the present disclosure, the first vibration plate may be disposed at the third portion.

[0160] According to some embodiments of the present disclosure, the sound generator may be disposed at the opening and the third portion.

[0161] According to some embodiments of the present disclosure, the outer frame may include a plurality of second vibration plates and be disposed at the second portion.

[0162] According to another embodiment of the present disclosure, a sound generating device may include: a piezoelectric device; a first weight member disposed at a first portion of the piezoelectric device; a second weight member disposed at a second portion of the piezoelectric device; a first elastic member disposed at a third portion between the first portion and the second portion of the piezoelectric device; and a protection member configured to cover the piezoelectric device, the first weight member, the second weight member, and the first elastic member.

[0163] According to some embodiments of the present disclosure, the third portion of the piezoelectric device may be configured to be fixed between two vibration plates through the first elastic member, and the sound generator may be configured to be surrounded by the outer frame and the two vibration plates.

[0164] According to some embodiments of the present disclosure, the second portion of the piezoelectric device may be configured to be fixed between two vibration plates through the second elastic member.

[0165] According to some embodiments of the present disclosure, the sound generating device may further include an inner frame disposed at an area surrounded by the outer frame, and the inner frame may be configured such that at least one of the sound generated by the third portion of the outer frame and the sound generated by the outer frame is introduced into a space formed at a part within the space surrounded by the outer frame and the two vibrating plates and reverberates.

[0166] According to some embodiments of the present disclosure, the sound generating device may further include a port located at the outer frame in a manner communicating with the space surrounded by the outer frame and the two vibrating plates.

[0167] According to some embodiments of the present disclosure, the sound generating device may further include another port disposed in the outer frame adjacent to the opening portion in a manner communicating with the space surrounded by the outer frame and the two vibrating plates.

[0168] Obviously, for those skilled in the art, various modifications and variations can be made to the present disclosure without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure is intended to cover these modifications and variations of the present disclosure as long as they fall within the scope of the appended claims and their equivalents.

Claims

1. A sound generator, comprising: A piezoelectric device having a rectangular plate shape and including a first portion to a third portion in the longitudinal direction of the piezoelectric device; A first counterweight member provided at the first portion of the piezoelectric device; A second counterweight member provided at the second portion of the piezoelectric device; A first elastic member provided at the third portion between the first portion and the second portion of the piezoelectric device; And A protective member configured to cover the piezoelectric device, the first counterweight member, the second counterweight member, and the first elastic member.

2. The sound generator according to claim 1, wherein, The piezoelectric device generates sounds in different audio segments at the first portion to the third portion respectively.

3. The sound generator according to claim 1, wherein, The piezoelectric device generates a high audio segment at the first portion, a low audio segment at the second portion, and a mid audio segment between the high audio segment and the low audio segment at the third portion.

4. The sound generator according to claim 1, further comprising a second elastic member provided at the second portion of the piezoelectric device.

5. The sound generator according to claim 4, wherein, The second elastic member includes an elastic material that is more deformable than the material of the first elastic member.

6. The sound generator according to claim 4, wherein, The second elastic member includes an elastic material having a density lower than the density of the first elastic member.

7. The sound generator according to claim 1, wherein, The size of the second portion is larger than the size of each of the first portion and the third portion.

8. The sound generator according to claim 1, wherein The protective member includes an elastic material, and the protective member surrounds the piezoelectric device, the first counterweight member, the second counterweight member, and the first elastic member.

9. The sound generator according to claim 4, wherein, In the longitudinal direction of the piezoelectric device, the first elastic member is at a position closer to one end of the piezoelectric device than the center in the longitudinal direction of the piezoelectric device.

10. A sound generating device, comprising: The sound generator according to any one of claims 1 to 9; And An outer frame configured to cover the sound generator, the outer frame including an opening portion and two first vibrating plates, Wherein, the sound generator is provided at the opening portion.

11. The sound generating device according to claim 10, wherein, The outer frame includes a first frame portion that generates a high audio segment, a second frame portion that generates a low audio segment, and a third frame portion that generates a mid audio segment between the first frame portion and the second frame portion.

12. The sound generating device according to claim 11, wherein, The opening portion is provided at the first frame portion.

13. The sound generating device according to claim 11, wherein, The sound generator is provided at the third frame portion.

14. The sound generating device according to claim 11, wherein, The sound generator is provided at the opening portion and the third portion.

15. The sound generating device according to claim 11, wherein, The outer frame includes a plurality of second vibrating plates.

16. The sound generating device according to claim 15, Among them, The third portion of the piezoelectric device is configured to be fixed between two first vibrating plates through the first elastic member, and Wherein, the sound generator is configured to be surrounded by the outer frame.

17. The sound generating device according to claim 16, wherein, The second portion of the piezoelectric device is configured to be fixed between the two first vibrating plates through the second elastic member.

18. The sound generating device according to claim 11 further includes an inner frame disposed at an area surrounded by the outer frame, Among them, The inner frame is configured such that at least one of the sound generated by the third portion of the piezoelectric device and the sound generated by the second portion of the piezoelectric device is introduced into a space at a part inside the sound generating device and reverberates.

19. The sound generating device according to claim 18 further includes a port located at the outer frame in a manner communicating with the space surrounded by the outer frame.

20. The sound generating device according to claim 19 further includes another port located at the outer frame adjacent to the opening portion in a manner communicating with the space surrounded by the outer frame.

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