Vibration speaker of vehicle and control method thereof

Abstract

The present invention relates to a vibration speaker of a vehicle and a control method thereof. The vibration speaker includes: a housing, a vibration membrane, a vibration member, a voice coil, a solenoid driver, an amplifier and a controller; the vibration membrane covers the open side of the housing and has an edge fixed to the housing; the vibration member is installed in the housing to vibrate in the vibration direction of the vibration membrane and has a magnet that forms a magnetic field; the voice coil is installed on the inner surface of the vibration membrane and is configured to vibrate the vibration membrane through interaction with the vibration member; the solenoid driver is fixed in the housing and is configured to form a magnetic field that controls the vibration of the vibration member; the amplifier is configured to apply a first output signal to the voice coil and apply a second output signal having a phase difference with the first output signal to the solenoid driver; the controller is configured to determine whether to apply the second output signal by comparing the frequency of the first output signal with the resonant frequency.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Korean Patent Application No. 10-2020-0020065 filed on February 19, 2020, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to a vibration speaker of a vehicle capable of improving bass output and a control method thereof. Background Art

[0004] Electric vehicles (EVs), plug-in hybrid electric vehicles (PHEVs), and hybrid electric vehicles (HEVs) powered by electric motors pose a risk of hitting pedestrians because they may only make minimal noise while driving. Therefore, these vehicles can use a Virtual Engine Sound System (VESS) that uses a vibration speaker to generate engine noise to reduce the occurrence of pedestrian collisions.

[0005] A vibration speaker used in a virtual engine sound system generally includes: a housing; a diaphragm disposed on a portion of the housing; a voice coil coupled to the diaphragm; and a vibration member configured with a magnet in the housing to operate the voice coil in a vibrating state. Such a vibration speaker can have excellent durability, a small size, and a low price.

[0006] However, the disadvantage of existing vibration speakers is that the bass output is lower than that of conventional speakers. A vibration speaker may have a diaphragm with a higher spring constant, so the resonant frequency is higher, resulting in a lower bass output. Since the vibration speaker vibrates, the diaphragm and the vibration member have a phase difference of almost 180° in the interval above the resonant frequency, and the magnetic flux interlinked between the voice coil and the vibration member is reduced, resulting in a lower output. Specifically, in the bass interval where the displacement of the vibration is large, the sound output is deteriorated. Summary of the invention

[0007] Accordingly, an aspect of the present invention provides a vibration speaker for a vehicle capable of improving bass output and a control method thereof.

[0008] According to one aspect of the present invention, a vibration speaker includes: a shell, a vibration membrane, a vibration member, a voice coil, a solenoid driver, an amplifier and a controller; the vibration membrane covers the open side of the shell and has an edge fixed to the shell; the vibration member is installed in the shell to vibrate in the vibration direction of the vibration membrane and has a magnet that forms a magnetic field; the voice coil is installed on the inner surface of the vibration membrane and is configured to vibrate the vibration membrane through interaction with the vibration member; the solenoid driver is fixed in the shell and is configured to form a magnetic field that controls the vibration of the vibration member; the amplifier is configured to apply a first output signal to the voice coil and apply a second output signal having a phase difference with the first output signal to the solenoid driver; the controller is configured to determine whether to apply the second output signal by comparing the frequency of the first output signal with the resonant frequency.

[0009] The vibration speaker may further include: a position sensor installed in the housing and configured to detect a position of the vibration member through distance sensing.

[0010] The vibration speaker may further include: a magnetic shield surrounding the outside of the solenoid driver except for a region facing the vibration member.

[0011] The controller may be configured to: control the amplifier to apply the second output signal when the frequency of the first output signal is greater than or equal to the resonance frequency; and block the second output signal when the frequency of the first output signal is less than the resonance frequency.

[0012] The controller may be configured to control the amplifier to apply the second output signal having a phase difference of 180° with respect to the first output signal when the frequency of the first output signal is higher than the resonance frequency.

[0013] The controller may be configured to control the amplifier to apply the second output signal having a 90° phase difference with respect to the first output signal when the frequency of the first output signal is equal to the resonance frequency.

[0014] The controller can be configured to: when the distance between the position sensor and the vibration component is within a set distance range, control the amplifier to maintain the strength of the second output signal; when the distance between the position sensor and the vibration component is greater than the set distance range, reduce the strength of the second output signal; when the distance between the position sensor and the vibration component is less than the set distance range, increase the strength of the second output signal.

[0015] According to another aspect of the present invention, a control method of a vibration speaker includes: setting the vibration speaker, and when the frequency of the first output signal is higher than the resonance frequency, controlling the application of a second output signal having a phase difference of 180° relative to the first output signal.

[0016] According to another aspect of the present invention, a control method of a vibration speaker includes: setting the vibration speaker, and when the frequency of the first output signal is equal to the resonance frequency, controlling the application of a second output signal having a 90° phase difference with respect to the first output signal.

[0017] According to another aspect of the present invention, a control method for a vibration speaker includes: providing a position sensor, which is installed in a shell and configured to detect the position of a vibration member by distance sensing; when the distance between the position sensor and the vibration member is within a set distance range, maintaining the intensity of a second output signal; when the distance between the position sensor and the vibration member is greater than the set distance range, reducing the intensity of the second output signal; when the distance between the position sensor and the vibration member is less than the set distance range, increasing the intensity of the second output signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Some aspects and / or other aspects of the present invention will become clear and more easily understood through the following description of embodiments in conjunction with the accompanying drawings, in which:

[0019] Figure 1 The configuration of a vibration speaker according to an embodiment of the present invention is shown.

[0020] Figure 2 The operation of the vibration member when the vibration speaker according to the embodiment of the present invention is operated is shown.

[0021] Figure 3 Detailed description is a flow chart showing a method of controlling a vibration speaker according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] It should be understood that the term "vehicle" or "vehicle-based" or other similar terms used herein generally include motor vehicles, such as passenger cars including sport utility vehicles (SUVs), buses, trucks, various commercial vehicles, ships including various boats, vessels, aircraft, etc., and include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., fuels derived from non-fossil energy sources). As referred to herein, a hybrid vehicle is a vehicle having two or more power sources, such as both gasoline-powered and electric-powered vehicles.

[0023] The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used herein, the singular forms "one", "an" and "the" are intended to also include plural forms, unless the context clearly indicates otherwise. It should be further understood that when the terms "including" and / or "including" are used in this specification, it is indicated that there are the features, numerical values, steps, operations, elements and / or components, but it is not excluded that there are or add one or more other features, numerical values, steps, operations, elements, components and / or their groups. As used herein, the term "and / or" includes any and all combinations of one or more related enumeration items. Throughout the specification, unless explicitly described to the contrary, the term "including" and variations such as "including" or "including" should be understood to imply the inclusion of the elements but do not exclude any other elements. In addition, the terms "unit", "device", "component" and "module" described in the specification are meant to be units for performing at least one function and operation, and can be implemented by hardware components or software components and their combinations.

[0024] In addition, the control logic of the present application can be implemented as a non-transitory computer readable medium on a computer readable medium, which contains executable program instructions executed by a processor, a controller, etc. Examples of computer readable media include, but are not limited to, ROM, RAM, compact disc (CD)-ROM, magnetic tape, floppy disk, flash drive, smart card, and optical data storage device. The computer readable medium can also be distributed on a network-connected computer system so that the computer readable medium is stored and executed in a distributed manner, for example, through a telematics server or a controller area network (CAN).

[0025] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are presented to fully convey the concept of the present invention to those of ordinary skill in the art to which the present invention belongs, and are not limited to those embodiments presented herein, and may be implemented in other forms. In order to make the present invention clear, the drawings may omit parts of the description that are not relevant to the specification, and the size of the components may be exaggerated to facilitate understanding.

[0026] refer to Figure 1 , a vibration speaker according to an embodiment of the present invention includes: a housing 10 , a diaphragm 20 , a voice coil 30 , a vibration member 40 , a solenoid driver 50 , an amplifier 60 , a position sensor 70 , and a controller 80 .

[0027] The housing 10 may be provided in a substantially cylindrical shape and have a space for accommodating the vibration member 40 and the solenoid driver 50. The housing 10 may have a shape in which one surface connected with the vibration membrane 20 is open and the opposite side is closed.

[0028] The diaphragm 20 may have an edge fixed to an opening side end portion of the housing 10 to cover one open surface of the housing 10. The diaphragm 20 may be provided as a thin plate, and may generate sound by vibrating.

[0029] The voice coil 30 is mounted on the inner surface of the diaphragm 20, and can vibrate the diaphragm 20 by interacting with the vibration member 40. The voice coil 30 may be in the form of a coil wound on the outer surface of a cylindrical bobbin, wherein one end of the cylindrical bobbin is attached to the inner surface of the diaphragm 20. A high-frequency AC current in an audio frequency band is applied to the voice coil 30.

[0030] The vibration member 40 is supported by a plurality of elastic members 12 connecting the outer side of the vibration member 40 and the inner surface of the housing 10, so that it can vibrate in the housing 10 along the vibration direction of the vibration membrane 20. Here, a form in which the elastic member 12 is connected to the outside of the vibration member 40 is shown, but the installation position of the elastic member 12 can be changed.

[0031] The vibration member 40 includes a magnet 41, a first yoke 42, and a second yoke 43; the first yoke 42 is connected to one end of the magnet 41 facing the vibration membrane 20 and is arranged in a disk shape capable of entering the inner space of the voice coil 30; the second yoke 43 is connected to the other end of the magnet 41 opposite to the first yoke 42. The second yoke 43 has a diameter greater than the outer diameter of the voice coil 30, and has a cylindrical extension 43a extending from the edge to surround the outside of the voice coil 30.

[0032] refer to Figure 2 In part (a), the voice coil 30 is located in a spaced-apart state in the gap 44 between the first yoke 42 and the second yoke 43 of the vibration member 40, and in the magnet 41, the N pole and the S pole are polarized toward the first yoke 42 side and the second yoke 43 side to form a magnetic field passing through the voice coil 30. Therefore, when an output signal (current signal) is applied to the voice coil 30, the diaphragm 20 vibrates, sound is output, and the vibration member 40 may also vibrate.

[0033] like Figure 1 As shown, the solenoid driver 50 is fixed to the inner surface of the housing 10 facing the second yoke 43 of the vibration member 40. The center line of the solenoid driver 50 may coincide with the line passing through the center of the vibration member 40. The solenoid driver 50 includes a central core 51 and a coil 52 wound around the core 51.

[0034] The solenoid driver 50 forms a magnetic field that controls the vibration of the vibration member 40 through the input current signal. The magnetic field of the solenoid driver 50 can change the magnetic field that affects the vibration member 40 by changing the phase of the input current signal and the strength of the current signal. In this way, the vibration of the vibration member 40 can be controlled.

[0035] The amplifier 60 includes a first signal outputter 61 for applying a first output signal S1 to the voice coil 30 and a second signal outputter 62 for applying a second output signal S2 to the solenoid driver 50. When an input signal is applied from the signal inputter 65, the amplifier 60 can vibrate the diaphragm 20 by applying the first output signal S1 to the voice coil 30. As needed, by applying the second output signal S2 having a different phase from the first output signal S1 to the solenoid driver 50, the amplifier 60 can adjust the vibration of the vibration member 40 by forming a magnetic field in the solenoid driver 50.

[0036] The controller 80 may control the amplifier 60 to apply or block the second output signal S2 according to the state of the first output signal S1. When the frequency of the first output signal S1 is greater than or equal to the resonant frequency of the vibration speaker, the controller 80 applies the second output signal S2 to the solenoid driver 50. When the frequency of the first output signal S1 is less than the resonant frequency, the controller 80 may control the amplifier 60 to block the second output signal S2.

[0037] In a typical vibration speaker, when the frequency of the first output signal S1 is less than the resonant frequency, there is almost no vibration phase difference between the diaphragm 20 and the vibration member 40; when the frequency of the first output signal S1 is equal to the resonant frequency, the vibrations of the diaphragm 20 and the vibration member 40 have a phase difference of 90°. In addition, when the frequency of the first output signal S1 exceeds the resonant frequency, the vibrations of the diaphragm 20 and the vibration member 40 have a phase difference of almost 180°. Therefore, in an ordinary vibration speaker, when the first output signal S1 applied to the voice coil 30 is greater than or equal to the resonant frequency, the sound output may decrease because the phase difference between the diaphragm 20 and the vibration member 40 is too large and the magnetic flux interlinked between the voice coil 30 and the vibration member 40 is reduced. This phenomenon may be exacerbated in the bass range where the vibration displacement is large.

[0038] However, in the vibration speaker of the present embodiment, when the first output signal S1 is greater than or equal to the resonance frequency, the solenoid driver 50 can adjust the vibration of the vibration member 40 to reduce the phase difference between the diaphragm 20 and the vibration member 40. Therefore, it is possible to avoid the sound output from being deteriorated in the low-pitched interval. That is, the bass output can be improved.

[0039] When the frequency of the first output signal S1 is higher than the resonance frequency, the controller 80 can reduce the vibration phase difference between the vibration membrane 20 and the vibration member 40 by applying the second output signal S2 having a 180° phase difference with respect to the first output signal S1. In addition, when the frequency of the first output signal S1 is equal to the resonance frequency, the controller 80 can reduce the vibration phase difference between the vibration membrane 20 and the vibration member 40 by applying the second output signal S2 having a 90° phase difference with respect to the first output signal S1. When the frequency of the first output signal S1 is lower than the resonance frequency, the controller 80 can control to block the second output signal S2.

[0040] refer to Figure 1 , the vibration speaker may include a magnetic shield 90 surrounding the outside of the remaining portion of the solenoid driver 50 except for the area facing the vibration member 40 .

[0041] The magnetic shield 90 is made of a non-magnetic material and may be in the form of a cup surrounding the periphery and bottom of the solenoid driver 50. The magnetic shield 90 minimizes leakage of the magnetic field generated by the solenoid driver 50 to the surroundings, thereby improving the effect of the solenoid driver 50 in controlling the vibration of the vibration member 40. In the present embodiment, a cup-shaped magnetic shield 90 is shown, but it is not limited thereto, and the shape of the magnetic shield 90 may be variously changed.

[0042] like Figure 1 As shown, the vibration speaker may include a position sensor 70 that senses the position of the vibration member 40 by distance measurement. The position sensor 70 is fixed to the inner surface of the housing 10 and can measure the behavior of the vibration member 40 by sensing the interval distance when the vibration member 40 vibrates.

[0043] like Figure 2 As shown in part (a) of FIG. 1 , in a vibration speaker, when the position where the magnetic flux flows from the first yoke 42 of the vibration member 40 to the second yoke 43 coincides with the position of the voice coil 30, the vibration of the diaphragm 20 increases as the magnetic flux interlinked with the voice coil 30 is maximized, thereby improving the sound output. That is, as Figure 2 As shown in part (a) of , when the strength of the magnetic field F of the solenoid driver 50 is appropriately maintained so that the distance L1 between the position sensor 70 and the vibration member 40 remains within a set distance range (when the vibration element stays near the "X" line and vibrates), the vibration speaker can exhibit optimal efficiency.

[0044] However, if Figure 2As shown in part (b) of FIG. 1 , in a vibration speaker, when the intensity of the magnetic field F of the solenoid driver 50 is too large, the output may be deteriorated when the distance L2 between the position sensor 70 and the vibration member 40 remains greater than the set distance range and the magnetic flux path of the vibration member 40 is offset from the position of the voice coil 30. Similarly, Figure 2 As shown in part (c) of FIG. 1 , in a vibration speaker, when the intensity of the magnetic field F of the solenoid driver 50 is too small, the output may also deteriorate when the distance L3 between the position sensor 70 and the vibration member 40 remains less than the set distance range and the magnetic flux path of the vibration member 40 is offset from the position of the voice coil 30 .

[0045] Therefore, in the vibration speaker of the present embodiment, based on the detection information of the position sensor 70, the intensity of the second output signal S2 applied to the solenoid driver 50 is controlled by the controller 80, and the position of the vibration member 40 is always maintained as follows: Figure 2 The example shown in part (a) shows the optimal state, which can prevent the sound output from deteriorating.

[0046] That is to say, when the distance between the position sensor 70 and the vibration component 40 is within the set distance range, the controller 80 can maintain the intensity of the second output signal S2; when the distance between the position sensor 70 and the vibration component 40 is greater than the set distance range, the controller 80 can reduce the intensity of the second output signal S2; when the distance between the position sensor 70 and the vibration component 40 is less than the set distance range, the controller 80 can control the amplifier 60 to increase the intensity of the second output signal S2.

[0047] Next, we will refer to Figure 3 The flow chart describes the control method of the vibration speaker.

[0048] The controller 80 detects the first output signal S1 output from the amplifier 60 (step 101 ), and determines whether the frequency of the first output signal S1 is higher than the resonance frequency (step 102 ).

[0049] When it is determined in step 102 that the frequency of the first output signal S1 is higher than the resonance frequency, the controller 80 controls the amplifier 60 to output the second output signal S2 having a phase difference of 180° with respect to the first output signal S1 (step 105 ).

[0050] When it is determined in step 102 that the frequency of the first output signal S1 is not higher than the resonant frequency, the controller 80 determines whether the frequency of the first output signal S1 is equal to the resonant frequency (step 103). Here, when it is determined that the frequency of the first output signal S1 is the same as the resonant frequency, the controller 80 controls the amplifier 60 to output the second output signal S2 having a 90° phase difference with respect to the first output signal S1 (step 106).

[0051] When it is determined in step 103 that the frequency of the first output signal S1 is not equal to the resonant frequency, the controller 80 determines whether the frequency of the first output signal S1 is lower than the resonant frequency (step 104). Here, when it is determined that the frequency of the first output signal S1 is lower than the resonant frequency, the controller 80 controls the amplifier 60 to block the second output signal S2 (step 107), and performs step 101 again.

[0052] After step 105 and step 106, the controller 80 detects the distance L between the position sensor 70 and the vibration member 40 through the position sensor 70 (step 108), and determines whether the distance L between the position sensor 70 and the vibration member 40 is within the set distance range (step 109). In step 109, when the distance L between the position sensor 70 and the vibration member 40 is within the set distance range, the controller 80 controls the amplifier 60 to maintain the strength of the second output signal S2 (step 112).

[0053] When it is determined in step 109 that the distance L between the position sensor 70 and the vibration member 40 is not within the set distance range, the controller 80 determines whether the distance L between the position sensor 70 and the vibration member 40 is greater than the set distance range (step 110 ).

[0054] When the distance L between the position sensor 70 and the vibration member 40 is greater than the set distance range in step 110, the controller 80 controls the amplifier 60 to reduce the intensity of the second output signal S2 (step 113). When it is determined in step 110 that the distance L between the position sensor 70 and the vibration member 40 is not greater than the set distance range, the controller 80 determines whether the distance L between the position sensor 70 and the vibration member 40 is less than the set distance range (step 111), and when the distance L between the position sensor 70 and the vibration member 40 is less than the set distance range, the controller 80 controls the amplifier 60 to increase the intensity of the second output signal S2 (step 114).

[0055] As described above, the vibration speaker according to the present embodiment controls the vibration of the vibration member 40 by controlling the second output signal S2 applied to the solenoid driver 50 according to whether the first output signal S1 is greater than or equal to the resonance frequency, and controls the intensity of the second output signal S2 applied to the solenoid driver 50 according to the position of the vibration member 40, so that the vibration member 40 can always be maintained at the optimal position, thereby preventing the output of the sound from decreasing in the low-pitched interval.

[0056] Since the solenoid driver can adjust the vibration of the vibration member when the first output signal is higher than the resonance frequency, the vibration speaker according to the embodiment of the present invention can prevent the output of the sound in the bass range from decreasing, that is, the bass output can be improved.

[0057] Since the vibration member can always be maintained at an optimal position by controlling the intensity of the second output signal applied to the solenoid driver according to the position of the vibration member, the vibration speaker according to the present embodiment can prevent the output of sound in the low-pitched tone range from being deteriorated.

[0058] So far, embodiments of the present invention have been described with reference to the accompanying drawings. It is obvious to those skilled in the art that the present invention can be practiced in other forms than the above embodiments without changing the technical concept or basic features of the present invention. The above embodiments are only examples and should not be interpreted as limiting.

Claims

1. A vibration speaker, comprising: case; a diaphragm covering the open side of the housing and having an edge fixed to the housing; a vibration member installed in the housing to vibrate in a vibration direction of the vibration film and having a magnet forming a magnetic field; a voice coil mounted on an inner surface of the diaphragm and configured to vibrate the diaphragm by interacting with a vibration member; a solenoid driver fixed in the housing and configured to form a magnetic field that controls vibration of the vibration member; an amplifier configured to apply a first output signal to the voice coil and to apply a second output signal having a phase difference with the first output signal to the solenoid driver; as well as a controller configured to determine whether to apply a second output signal by comparing a frequency of the first output signal with a resonant frequency; Wherein, the controller is configured to: when the frequency of the first output signal is greater than or equal to the resonant frequency, control the amplifier to apply the second output signal; when the frequency of the first output signal is less than the resonant frequency, block the second output signal.

2. The vibration speaker according to claim 1, further comprising: A position sensor is installed in the housing and is configured to detect a position of the vibration member through distance sensing.

3. The vibration speaker according to claim 1, further comprising: A magnetic shield surrounds the exterior of the solenoid actuator except for an area facing the vibrating member.

4. The vibration speaker according to claim 1, wherein: The controller is configured to control the amplifier to apply a second output signal having a phase difference of 180° with respect to the first output signal when the frequency of the first output signal is higher than the resonance frequency.

5. The vibration speaker according to claim 1, wherein: The controller is configured to control the amplifier to apply a second output signal having a 90° phase difference with respect to the first output signal when the frequency of the first output signal is equal to the resonance frequency.

6. The vibration speaker according to claim 2, wherein: The controller is configured to: when the distance between the position sensor and the vibration component is within a set distance range, control the amplifier to maintain the strength of the second output signal; when the distance between the position sensor and the vibration component is greater than the set distance range, reduce the strength of the second output signal; when the distance between the position sensor and the vibration component is less than the set distance range, increase the strength of the second output signal.

7. A control method for a vibration speaker, the control method comprising: A vibration speaker is provided, comprising: case; a diaphragm covering the open side of the housing and having an edge fixed to the housing; a vibration member installed in the housing to vibrate in a vibration direction of the vibration film and having a magnet forming a magnetic field; a voice coil mounted on an inner surface of the diaphragm and configured to vibrate the diaphragm by interacting with a vibration member; a solenoid driver fixed in the housing and configured to form a magnetic field that controls vibration of the vibration member; an amplifier configured to apply a first output signal to the voice coil and to apply a second output signal having a phase difference with the first output signal to the solenoid driver; and a controller configured to determine whether to apply a second output signal by comparing a frequency of the first output signal with a resonant frequency; When the frequency of the first output signal is higher than the resonance frequency, the second output signal having a phase difference of 180° with respect to the first output signal is controlled to be applied.

8. The control method according to claim 7, further comprising: providing a position sensor mounted in the housing and configured to detect a position of the vibration member by distance sensing; When the distance between the position sensor and the vibration component is within a set distance range, maintaining the intensity of the second output signal; When the distance between the position sensor and the vibration component is greater than a set distance range, reducing the intensity of the second output signal; When the distance between the position sensor and the vibration component is less than a set distance range, the intensity of the second output signal is increased.

9. A control method for a vibration speaker, the control method comprising: A vibration speaker is provided, comprising: case; a diaphragm covering the open side of the housing and having an edge fixed to the housing; a vibration member installed in the housing to vibrate in a vibration direction of the vibration film and having a magnet forming a magnetic field; a voice coil mounted on an inner surface of the diaphragm and configured to vibrate the diaphragm by interacting with a vibration member; a solenoid driver fixed in the housing and configured to form a magnetic field that controls vibration of the vibration member; an amplifier configured to apply a first output signal to the voice coil and to apply a second output signal having a phase difference with the first output signal to the solenoid driver; and a controller configured to determine whether to apply a second output signal by comparing a frequency of the first output signal with a resonant frequency; When the frequency of the first output signal is equal to the resonance frequency, the second output signal having a 90° phase difference with respect to the first output signal is controlled to be applied.

10. The control method according to claim 9, further comprising: providing a position sensor mounted in the housing and configured to detect a position of the vibration member by distance sensing; When the distance between the position sensor and the vibration component is within a set distance range, maintaining the intensity of the second output signal; When the distance between the position sensor and the vibration component is greater than a set distance range, reducing the intensity of the second output signal; When the distance between the position sensor and the vibration component is less than a set distance range, the intensity of the second output signal is increased.

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