A screen vibration exciter

Abstract

The present invention discloses a screen vibration exciter, which is used for exciting screen vibration. The screen vibration exciter comprises a protective shell connected to the screen and a vibrating member arranged in the protective shell. The vibrating member and the protective shell are connected via an elastic suspension. The vibrating member vibrates in a controlled manner and drives the protective shell to vibrate via the elastic suspension, thereby driving the screen to vibrate. A counterweight block is also provided in the vibrating member. By changing the weight of the counterweight block and / or the compliance of the elastic suspension, the screen can have different eigenfrequencies when vibrating, thereby adjusting the vibration characteristics of the screen and effectively improving the sound quality of the vibration sound output of the screen.

Description

Technical Field

[0001] The invention relates to the field of electroacoustic conversion, and in particular to a screen vibration exciter. Background Art

[0002] At present, the screen sound excitation devices of electronic devices are mainly divided into two types: electromagnetically driven screen vibration sound and piezoelectrically driven screen vibration sound. Electromagnetic driven screen sound is based on the electromagnetic induction phenomenon of the energized coil in the magnetic field to drive the screen to make sound. The vibration frequency is difficult to adjust, and the output tone and sound quality are poor. Summary of the invention

[0003] In view of this, an object of the present invention is to provide a screen vibration exciter that can effectively improve the output sound quality.

[0004] An embodiment of the present invention provides a screen vibration exciter for exciting screen vibration, the screen vibration exciter comprising:

[0005] A protective shell connected to the screen, wherein the protective shell has a storage space;

[0006] a vibrating member disposed in the accommodating space and configured to vibrate in a controlled manner, wherein a counterweight block is further disposed on the vibrating member; and

[0007] An elastic suspension, connecting the protective shell and the vibrating member, so that the vibrating member drives the protective shell and the screen to vibrate synchronously;

[0008] The weight of the counterweight block and / or the compliance of the elastic suspension are set to enable the screen to have a predetermined eigenfrequency when vibrating.

[0009] Preferably, the vibrating member comprises:

[0010] a magnetic circuit system, disposed in the accommodation space and not in contact with the protective shell, the magnetic circuit system being used to generate a magnetic field, the counterweight being disposed in the magnetic circuit system; and

[0011] A voice coil configured to be driven by the magnetic field and thereby excite the magnetic circuit system (2) to vibrate;

[0012] The elastic suspension connects the protective shell and the magnetic circuit system.

[0013] Preferably, the magnetic circuit system comprises:

[0014] magnet;

[0015] a yoke, forming the magnetic field with the magnet; and

[0016] The pole piece is arranged on the magnet and is used for magnetic conduction.

[0017] Preferably, the pole piece has at least one notch, and the notch is at least partially filled with magnetic glue;

[0018] Preferably, the pole piece is a rectangular pole piece, and four notches are provided and are respectively located at the four corners of the pole piece.

[0019] Preferably, the yoke comprises a plate-shaped body and a protrusion, wherein the protrusion is formed by protruding upward from the upper surface of the plate-shaped body;

[0020] The magnet is disposed on the upper surface and is spaced apart from the protrusion by a distance, thereby forming a magnetic gap between the magnet and the protrusion, and the magnetic field exists in the magnetic gap;

[0021] Preferably, the protrusion is formed by an edge of the plate-like body protruding upward, and surrounds at least a portion of the edge of the plate-like body.

[0022] Preferably, the magnet is an annular magnet having a first annular hole;

[0023] The pole piece is an annular pole piece, having a second annular hole, and the second annular hole is at least partially connected to the first annular hole;

[0024] The counterweight is at least partially located in the first annular hole and the second annular hole;

[0025] Preferably, the plate-like body further has a through hole at least partially connected to the first annular hole, and the counterweight block is at least partially located in the through hole.

[0026] Preferably, the protective shell comprises:

[0027] a front cover, the front cover comprising a first surface and a second surface opposite to the first surface, the first surface being connected to the screen, and the voice coil being connected to the second surface; and

[0028] a back cover, wherein an edge region of the back cover is fixedly connected to an edge region of the front cover, and a middle region of the back cover bulges away from the second surface to form a receiving space with the front shell;

[0029] Preferably, the elastic tab connects an edge region of the front cover and an upper end surface of the protrusion.

[0030] Preferably, the elastic suspension comprises:

[0031] A first connecting portion connected to an edge area of ​​the front cover;

[0032] A second connecting portion connected to the upper end surface of the protruding portion;

[0033] at least one connecting arm connecting the first connecting portion and the second connecting portion;

[0034] Preferably, the connecting arm is formed in a broken line shape.

[0035] Preferably, the protective shell is also provided with at least one vent hole;

[0036] Preferably, the ventilation hole is located on the rear shell.

[0037] The screen vibration exciter of the embodiment of the present invention is provided with a counterweight block in the vibrating member. The vibrating member drives the screen to vibrate through elastic suspension, and changes the weight of the counterweight block and / or the compliance of the elastic suspension piece, so that the screen has different natural frequencies when vibrating, thereby adjusting the vibration characteristics of the screen and effectively improving the sound quality of the screen vibration sound output. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0039] Figure 1 A schematic diagram of a screen vibration exciter according to an embodiment of the present invention being applied to an electronic device;

[0040] Figure 2 It is a cross-sectional view taken along line AA of an embodiment of the present invention;

[0041] Figure 3 An exploded view of a screen vibration exciter according to an embodiment of the present invention;

[0042] Figure 4 Schematic diagram of a front cover and a rear cover of an embodiment of the present invention;

[0043] Figure 5 A three-dimensional diagram of an elastic suspension according to an embodiment of the present invention;

[0044] Figure 6 A three-dimensional diagram of a yoke according to an embodiment of the present invention;

[0045] Figure 7 Schematic diagram of a pole piece and magnetic glue according to an embodiment of the present invention. DETAILED DESCRIPTION

[0046] The present invention is described below based on embodiments, but the present invention is not limited to these embodiments. In the detailed description of the present invention below, some specific details are described in detail. It is possible for a person skilled in the art to fully understand the present invention without the description of these details. In order to avoid confusing the essence of the present invention, known methods, processes, flows, components and circuits are not described in detail.

[0047] In addition, persons of ordinary skill in the art will appreciate that the drawings provided herein are for illustration purposes and are not necessarily drawn to scale.

[0048] At the same time, it should be understood that in the following description, "circuit" refers to a conductive loop composed of at least one element or subcircuit through electrical connection or electromagnetic connection. When an element or circuit is said to be "connected to" another element or an element / circuit is said to be "connected between" two nodes, it can be directly coupled or connected to another element or there can be an intermediate element, and the connection between the elements can be physical, logical, or a combination thereof. On the contrary, when an element is said to be "directly coupled to" or "directly connected to" another element, it means that there is no intermediate element between the two.

[0049] Unless the context clearly requires otherwise, words such as “include”, “including” and the like in the specification should be interpreted as including rather than being exclusive or exhaustive; that is, as meaning “including but not limited to”.

[0050] In the description of the present invention, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0051] At present, some electronic devices such as mobile phones and tablet computers use screen vibration to generate sound instead of traditional speaker modules as sound generating units. The screen vibration generates sound by vibrating a vibration exciter attached to the inner side of the screen. The vibration exciter can be piezoelectric or electromagnetic. This embodiment proposes a solution based on the above-mentioned vibration exciter to optimize the sound output quality.

[0052] Figure 1 FIG. 1 is a schematic diagram of an electronic device using a screen vibration exciter J according to an embodiment of the present invention. Figure 1 As shown, the screen vibration exciter J is connected to the screen P of the electronic device, and the edge of the screen P is fixed by a frame K. The screen vibration exciter J can be attached to the inner side of the screen P by gluing, and the inner side of the screen P also has a system-side component (not shown in the figure), such as a motherboard, etc. The screen vibration exciter J is separated from the system-side component by a certain distance, so that the screen vibration exciter J will not touch the system-side component when vibrating. In addition, it is easy to understand that the side of the screen P where the screen vibration exciter J is not attached is a display surface for displaying images.

[0053] like Figure 2 and Figure 3As shown, the screen vibration exciter J of the embodiment of the present invention includes a protective shell 3, and the protective shell 3 has a receiving space V. The receiving space V is provided with vibrators 1, 2. The vibrators 1, 2 are not in contact with the protective shell 3, but are connected to the protective shell 3 through an elastic suspension 4. The vibrators 1, 2 vibrate in a controlled manner, and the protective shell 3 is driven to vibrate synchronously through the elastic suspension 4, thereby driving the screen P to vibrate and make sounds. A counterweight M is also provided on the vibrators 1, 2.

[0054] The mass of the counterweight M and / or the compliance of the elastic suspension 4 are set so that the screen P has a predetermined eigenfrequency when vibrating. The compliance is relative to the rigidity and is related to the hardness of the elastic suspension 4; the eigenfrequency is related to the sound quality generated by the vibration.

[0055] Specifically, taking electronic equipment as the vibration system:

[0056]

[0057] C ms ∝C ms1 , C ms2

[0058] Among them, F0 is the eigenfrequency value of the system, M ms is the weight of the system, C ms For the compliance of the system.

[0059] C ms With C ms1 and C ms2 Positively correlated, C ms1 is the compliance of the elastic suspension 4, C ms2 For the compliance of screen P.

[0060] Furthermore, since the weight of the elastic suspension 4 is relatively light, the effect of the elastic suspension 4 on the vibration system can be ignored. However, the weight of the screen P has a predetermined weight when the electronic device is produced and is not suitable for adjustment. Therefore, the weight of the vibration components 1 and 2 has a significant effect on the weight M of the vibration system. ms Similarly, the compliance C of screen P ms2 If it is not suitable for adjustment, the compliance of the elastic suspension C ms1 Compliance C of the vibration system ms have an impact.

[0061] Therefore, the weight of the vibrating members 1 and 2 can be adjusted by adjusting the weight of the counterweight M, thereby adjusting the weight of the vibration system, and / or adjusting the compliance C of the elastic suspension 4. ms1 To adjust the compliance of the vibration system, and then adjust the system's eigenfrequency F0, so that the vibration system can obtain better low-frequency characteristics.

[0062] It is not difficult to understand that M msThe value of is positively correlated with the weight of the counterweight M. ms The value of the elastic suspension 4 is related to the compliance C ms1 There is a positive correlation between the eigenfrequency F0 and M ms and C ms That is to say, the heavier the vibration parts 1, 2 (counterweight M) and the softer the elastic suspension 4, the lower the natural frequency of the system and the better the low-frequency response characteristics.

[0063] The counterweight M is generally made of a material with a relatively high density, such as copper, tungsten, tungsten carbide, nickel-chromium alloy, and the like.

[0064] This embodiment provides a feasible solution based on the electromagnetic exciter. Figure 2 and Figure 3 As shown, the vibrating parts 1, 2 include a voice coil 1 and a magnetic circuit system 2. The magnetic circuit system 2 is arranged in the accommodating space V in the protective shell 3, and is not in direct contact with the protective shell 3, but is connected to the protective shell 3 through an elastic suspension 4, and the counterweight M is also arranged in the magnetic circuit system 2. The magnetic circuit system 2 is used to generate a magnetic field, and the voice coil 1 is arranged in the magnetic field, and is configured to receive an alternating current signal and be driven by the magnetic field to stimulate the magnetic circuit system 2 to vibrate. The magnetic circuit system 2 drives the protective shell 3 to vibrate synchronously through the elastic suspension 4, and then drives the screen P connected to the protective shell 3 to vibrate synchronously to produce sound.

[0065] See also Figure 2 and Figure 3 , the upper end of the protective shell 3 is connected to the screen P, and the voice coil 1 can be connected to the inner side of the upper end of the protective shell 3 (the outer side is connected to the screen P), and the connection method can be gluing. A connecting wire (not shown in the figure) is led out from the voice coil 1 and is electrically connected to a control unit of the electronic device (not shown in the figure), and the control unit is used to input a predetermined AC signal to the voice coil 1. After the AC signal is passed through the voice coil 1, it is subjected to the electromagnetic force given by the magnetic field generated by the magnetic circuit system 2. Based on Newton's third law, the magnetic circuit system 2 is also subjected to the reaction force given by the voice coil 1, and the direction of the reaction force is related to the direction of the AC signal input to the voice coil 1. The direction of the AC signal changes periodically, so the direction of the electromagnetic force received by the magnetic circuit system 2 also changes periodically, driving the magnetic circuit system 2 to reciprocate periodically in the opposite direction, thereby generating vibration.

[0066] like Figure 2 and Figure 4 As shown, the protective shell 3 may include a front cover 31 and a rear cover 32. The front cover 31 includes a first surface facing the screen P and a second surface opposite to the first surface. Figure 2In the embodiment, the first surface, i.e., the upper surface of the front cover 31, is connected to the screen P, and the second surface, i.e., the lower surface of the front cover 32, is connected to the voice coil 1. The edge area of ​​the front cover 31 is fixedly connected to the edge area of ​​the rear cover 32, and the middle area of ​​the rear cover 32 bulges away from the second surface, thereby forming a receiving space V between the front cover 31 and the rear cover 32.

[0067] The connection between the front cover 31 and the rear cover 32 in the edge area can be achieved by snapping, gluing or welding. Preferably, the snapping connection method is used, which is easy to disassemble and easy to install. The voice coil 1 is a coil winding with several turns, formed in a ring shape, and has a certain height. It can be connected to the inner surface of the middle area of ​​the front cover 31 through the upper end surface, which is similar to the connection between the voice coil 1 and the protective shell 3 mentioned above, and will not be repeated here.

[0068] The protective shell 3 is configured as a front cover 31 and a rear cover 32 , which can also make the process flow during structural processing and assembly more convenient.

[0069] In this embodiment, if Figure 4 As shown, the front cover 31 is formed with an upper buckle 311 in the edge area, and there are four upper buckles 311, which respectively avoid the four corners of the front cover 31, and protrude and extend from the four sides of the front cover 31 to the direction of the rear cover 32. The rear cover 32 is formed with a lower buckle 321 corresponding to the upper buckle 311 in the edge area, and the lower buckle 321 protrudes and extends from the edge area of ​​the rear cover 32 to the direction of the front cover 31. The front cover 31 and the rear cover 32 are fixedly connected by forming a snap fit through the upper buckle 311, the lower buckle 321, and the four corner avoidance areas located at the upper buckle 311 and the lower buckle 321. The elastic suspension 4 connects the edge area of ​​the front cover 31 and the magnetic circuit system 2.

[0070] Specifically, Figure 5 As shown, the elastic suspension 4 is formed into a hollow sheet structure, including a first connecting portion 41, a second connecting portion 42 and a connecting arm 43. Among them, the first connecting portion 41 is a rounded rectangular ring structure, which is used to connect with the edge area of ​​the front cover 31. The second connecting portion 42 is located on the inner side of the first connecting portion 41 and is separated from the first connecting portion 41 by a distance, and is used to connect with the magnetic circuit system 2. The first connecting portion 41 and the second connecting portion 42 are connected by a connecting arm 43. The connecting arm 43 is an arm-like structure, shaped like a pattern, and partially fills the inner side of the first connecting portion 41. Therefore, the elastic suspension 4 can also be regarded as a pattern hollow sheet with the first connecting portion 41 as the edge.

[0071] Next, in combination with the structure of the magnetic circuit system 2 , the connection between the front cover 31 and the magnetic circuit system 2 by the elastic suspension 4 will be further described.

[0072] like Figure 2 and Figure 3As shown, the magnetic circuit system 2 may include a magnet 21, a yoke 22 and a pole piece 23. The magnet 21 is disposed on the yoke 22, and the pole piece 23 is disposed on the magnet 21. The magnet 21 and the yoke 22 are used to generate a magnetic field, and the pole piece 23 is used to conduct magnetism.

[0073] Combination Figure 6 The yoke 22 may include a plate-shaped body 221 and a protrusion 222. The protrusion 222 is formed by the upper surface 2211 of the plate-shaped body 221 protruding upward. The magnet 21 is disposed on the upper surface 2211 and is spaced from the protrusion 222, thereby forming a magnetic gap between the magnet 21 and the protrusion 222, and the magnetic field exists in the magnetic gap.

[0074] In this embodiment, the protrusion 222 is formed by the edge of the plate-like body 221 protruding upward, and similar to the upper buckle 311 / lower buckle 321, it avoids the four corners and protrudes upward from the four sides of the plate-like body 221. Thus, the distribution of the magnetic field in space is more uniform.

[0075] Combination Figure 2 and Figure 3 As shown, the second connection part 42 of the elastic suspension 4 is connected to the upper end surface of the protrusion 222. The second connection part 42 is formed in a long strip shape, and there are four of them, which correspond to the four protrusions 222 respectively. The correspondence means that after the front cover 31 and the rear cover 32 are buckled, the second connection part 42 and the projection of the protrusion 222 in the longitudinal direction are almost completely overlapped. The upper end surface of the protrusion 222 can be pre-coated with adhesive so that after the front cover 31 and the rear cover 32 are buckled, the second connection part 42 is glued and connected to the upper end surface of the protrusion 222.

[0076] The connecting arm 43 is formed in a zigzag shape, and one connecting arm 43 is connected to each end of each second connecting portion 42, and a total of eight connecting arms 43 are provided. When the system vibrates, the first connecting portion 41 is connected to the front cover 31, and the second connecting portion 42 is connected to the magnetic circuit system 2. The connecting arm 43 serves as a medium for transmitting vibration, and transmits the vibration of the magnetic circuit system 2 to the protective shell 3. The zigzag-shaped connecting arm 43 enables it to have better vibration characteristics when vibrating, which helps to improve the overall vibration output quality of the system.

[0077] In addition, if Figure 2 and Figure 3 As shown, in this embodiment, the upper end surface of the voice coil 1 is connected to the protective shell 3 / front cover 31, and the lower end extends into the magnetic gap, and can be driven by the magnetic field in the magnetic gap to excite the magnetic circuit system 2 to vibrate.

[0078] like Figure 2 and Figure 7As shown, the outer contours of the magnet 21 and the pole piece 23 are rectangular or rounded rectangles, and the cross-sectional area is smaller than the cross-sectional area of ​​the voice coil 1, so that the voice coil 1 can extend into the magnetic gap.

[0079] The magnet 21 and the pole piece 23 can also be annular, and the outer contour is still a rectangle, or a rounded rectangle. The magnet 21 has a first annular hole 211, and the pole piece 23 has a second annular hole 232, and the second annular hole 232 is at least partially connected to the first annular hole 211. The counterweight M is at least partially located between the first annular hole 211 and the second annular hole 232. Preferably, the second annular hole 232 is completely connected to the first annular hole 211, so that the counterweight M is more firmly located between the first annular hole 211 and the second annular hole 232.

[0080] The plate-shaped body 221 may also have a through hole 2212 at least partially connected to the first ring hole 211, and the counterweight block M is at least partially located in the through hole 2212. Preferably, the through hole 2212 is also completely connected to the first ring hole 211, and the reason is not repeated. Figure 6 As shown, a stepped structure 2213 may be provided between the upper surface 2211 and the through hole 2212, and a stepped structure (easy to understand, not shown) having the same shape as the stepped structure 2213 and cooperating with each other is formed on the lower end surface of the counterweight block M, so that the counterweight block M is supported on the stepped structure 2213. Thus, the counterweight block M is sequentially passed through the second annular hole 232, the first annular hole 211 and the through hole 2212, and is supported by the stepped structure 2213, and can be fixed in the second annular hole 232, the first annular hole 211 and the through hole 2212, and will not fall out of the through hole 2212.

[0081] It should be understood that the counterweight M can also be disposed in one or two of the first annular hole 211, the second annular hole 232 and the through hole 2212, and can also be fixed in the magnetic circuit system 2. For example, the plate-shaped body 2211 of the yoke 22 does not have a through hole 2212, and the counterweight M is disposed in the first annular hole 211 and the second annular hole 232, and supported by the plate-shaped body 221.

[0082] like Figure 7 As shown, the pole piece 23 may also have at least one notch 231, and the notch 231 is at least partially filled with magnetic glue 231a. The magnetic glue 231a provides certain magnetic conductivity, improves the vibration and volume of the vibration sound, and the damping glue component in the magnetic glue 231a can increase the damping of the vibration system, adjust the vibration and timbre near the resonant frequency of the vibration system, and effectively suppress the generation of noise.

[0083] Preferably, the pole piece 23 has a notch 231 at each of the four corners, and the notch 231 is completely filled with magnetic glue 231a, and the magnetic glue 231a still forms a rectangular or rounded rectangular shape together with the pole piece 23 after being filled. Therefore, the magnetic conductivity and damping suppression characteristics of the magnetic glue 231a can be exerted to a greater extent.

[0084] like Figure 2 As shown, at least one vent hole 321 is also provided on the protective shell 3. In this embodiment, the vent hole 321 is located on the back cover 32. The vent hole 321 is used to connect the inner cavity and the outside of the screen vibration exciter J to balance the air pressure inside and outside the component. The number, size and location of the vent hole 321 are not limited and can be located at any location on the protective shell 3 / back cover 32.

[0085] In some other optional implementations, the screen vibration exciter J may also be a piezoelectric exciter. For example, the vibrating members 1 and 2 may include a piezoelectric sheet (not shown), a counterweight similar to the counterweight block M of this embodiment is provided on the piezoelectric sheet, and the piezoelectric sheet is connected to the housing through an elastic sheet similar to the elastic suspension sheet 4 of this embodiment, and the housing is similar to the protective shell 3 in this embodiment. Therefore, by using the counterweights of different weights and / or elastic sheets of different compliances, the output characteristics of the vibration system can also be optimized.

[0086] The screen vibration exciter of the embodiment of the present invention can adjust the eigenfrequency of the vibration system of the electronic device by changing the weight of the counterweight block and / or changing the compliance of the elastic suspension. The counterweight block can be made of a heavier material, and the elastic suspension can be made of a softer material to reduce the eigenfrequency of the system, expand the low-frequency bandwidth, and improve the low-frequency playback characteristics. The setting of the magnetic glue can effectively suppress the amplitude near the resonant frequency, suppress the generation of noise, and adjust the sound quality. The magnetic conductivity of the magnetic glue can also increase the vibration amplitude of the entire section, thereby improving the sensitivity of the entire frequency band. The screen vibration exciter of the present invention has good sound output quality.

[0087] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A screen vibration exciter, used to excite screen vibration, characterized in that: The screen vibration exciter comprises: A protective shell (3) connected to the screen, wherein the protective shell (3) has a receiving space (V); A vibrating member (1, 2) is arranged in the accommodating space (V) and is configured to vibrate in a controlled manner, the vibrating member (1, 2) comprising a magnetic circuit system (2) and a voice coil (1), the magnetic circuit system (2) being arranged in the accommodating space (V) and not in contact with the protective shell (3), the magnetic circuit system (2) being used to generate a magnetic field, one end of the voice coil (1) being connected to the protective shell (3), the other end of the voice coil (1) extending into the magnetic field and not in contact with the magnetic circuit system (2), the voice coil (1) being configured to be driven by the magnetic field and thereby stimulate the magnetic circuit system (2) to vibrate, the vibrating member (1, 2) being further provided with a counterweight (M), the counterweight (M) being arranged in the magnetic circuit system (2); and An elastic suspension (4) connects the protective shell (3) and the magnetic circuit system (2), so that the magnetic circuit system (2) drives the protective shell (3) and the screen to vibrate synchronously; The weight of the counterweight (M) and / or the compliance of the elastic suspension (4) are set so that the screen has a predetermined eigenfrequency when vibrating.

2. The screen vibration exciter according to claim 1, characterized in that: The magnetic circuit system (2) comprises: Magnet (21); a yoke (22) forming the magnetic field with the magnet (21); and The pole piece (23) is arranged on the magnet (21) and is used for magnetic conduction.

3. The screen vibration exciter according to claim 2, characterized in that: The pole piece (23) has at least one notch (231), and the notch (231) is at least partially filled with magnetic glue (231a).

4. The screen vibration exciter according to claim 3, characterized in that: The pole piece (23) is a rectangular pole piece, and four notches (231) are provided, and are respectively located at the four corners of the pole piece (23).

5. The screen vibration exciter according to claim 3, characterized in that: The yoke (22) comprises a plate-shaped body (221) and a protrusion (222), wherein the protrusion (222) is formed by an upper surface (2211) of the plate-shaped body (221) protruding upward; The magnet (21) is arranged on the upper surface (2211) and is spaced apart from the protrusion (222) to form a magnetic gap between the magnet (21) and the protrusion (222), and the magnetic field exists in the magnetic gap.

6. The screen vibration exciter according to claim 5, characterized in that: The protrusion (222) is formed by protruding upward from the edge of the plate-shaped body (221), and surrounds at least a portion of the edge of the plate-shaped body (221).

7. The screen vibration exciter according to claim 6, characterized in that: The magnet (21) is an annular magnet having a first annular hole (211); The pole piece (23) is an annular pole piece, having a second annular hole (232), and the second annular hole (232) is at least partially connected to the first annular hole (211); The counterweight (M) is at least partially located in the first annular hole (211) and the second annular hole (232).

8. The screen vibration exciter according to claim 7, characterized in that: The plate-like body (221) also has a through hole (2212) at least partially connected to the first annular hole (211), and the counterweight (M) is at least partially located in the through hole (2212).

9. The screen vibration exciter according to claim 5, characterized in that: The protective shell (3) comprises: a front cover (31), the front cover (31) comprising a first surface and a second surface opposite to the first surface, the first surface being connected to the screen, and the voice coil (1) being connected to the second surface; and A rear cover (32), wherein an edge region of the rear cover (32) is fixedly connected to an edge region of the front cover (31), and a middle region of the rear cover (32) bulges in a direction away from the second surface to form a receiving space (V) with the front cover (31).

10. The screen vibration exciter according to claim 9, characterized in that: The elastic hanging piece (4) connects the edge area of ​​the front cover (31) and the upper end surface of the protruding portion (222).

11. The screen vibration exciter according to claim 9, characterized in that: The elastic suspension (4) comprises: A first connecting portion (41) connected to an edge region of the front cover (31); A second connecting portion (42) connected to the upper end surface of the protruding portion (222); At least one connecting arm (43) connects the first connecting portion (41) and the second connecting portion (42).

12. The screen vibration exciter according to claim 11, characterized in that: The connecting arm (43) is formed in a broken line shape.

13. The screen vibration exciter according to claim 9, characterized in that: The protective shell (3) is provided with at least one air vent (321).

14. The screen vibration exciter according to claim 13, characterized in that: The rear cover (32) is provided with at least one air vent (321).

Images