Network new media noiseless audio-visual equipment
By introducing push-pull mechanism and fence adjustment components in network new media audio-visual equipment, the problem of fixing the speaker installation angle and difficult to adjust the sound diffusion range is solved, and flexible audio regulation and noise reduction effects are achieved.
Patent Information
- Application Number
- CN202510322937.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-19
- Publication Date
- 2025-06-20
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
In existing network new media audio-visual equipment, the speaker installation angle is fixed, and the main sound orientation area cannot be flexibly changed, and the sound diffusion range cannot be adjusted, making it difficult to control the concentrated sound state.
A new network media noise-free audio-visual device is designed, using a push-pull mechanism and a fence adjustment assembly, allowing the flexibly changing the sound direction and angle of the independent sounding unit without moving the entire device, and adjusting the sound diffusion range through the fence adjustment assembly.
It realizes the flexible adjustment of the sound emission direction and diffusion range without the overall mobile device, reduces vibration noise, and does not have a significant impact on surrounding people during the volume calibration process.
Smart Images

Figure HDA0005317932320000011 
Figure HDA0005317932320000021 
Figure HDA0005317932320000031
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of speakers, and specifically to a noise-free audio-visual device for network new media. Background Art
[0002] Audio-visual devices refer to devices used for audio-visual entertainment, information display and communication, mainly including televisions, stereos, projectors, video recorders, slide projectors, large-screen projectors, etc. These devices are widely used in scenarios such as home entertainment, commercial display, public broadcasting and in-vehicle audio-visual. Speakers play a crucial role in audio-visual devices. Speakers are an essential core component in an audio system, responsible for efficiently converting electrical energy into sound energy to ensure that music and sounds can be vividly presented to the audience. The quality and characteristics of speakers have a crucial impact on the overall sound quality of the audio system.
[0003] Existing network new media audio-visual devices in the prior art are equipped with a display unit and a speaker unit. However, for large audio-visual devices, the installation angle of the speakers is fixed and it is impossible to flexibly change the main sound-emitting orientation area. Only by directly carrying the entire device and rotating it can the angle be adjusted, which is time-consuming and laborious. On the other hand, conventional audio-visual devices cannot adjust the sound amplification range and cannot directly control the concentration state of the sound. Summary of the Invention
[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a noise-free audio-visual device for network new media to solve the problems raised in the above background art. The present invention can flexibly change the sound-emitting orientation and angle of any independent sound-emitting unit without moving the entire device, and cooperate with the enclosure adjustment component to adjust the diffusion range of the sound, achieving the adjustment purposes of concentrated sound diffusion and large-range diffusion, and can detect and calibrate whether the volume of each independent sound-emitting unit is consistent, and during the calibration process, it will not have a great impact on the surrounding people due to excessive volume.
[0005] To achieve the above object, the present invention is implemented through the following technical solutions: A network new media noise-free audio-visual device, including an audio-visual device body. The audio-visual device body includes end plates, a push-pull mechanism, a baffle adjustment component, and independent sound units. Extension plates are integrally formed on both sides of the end plates. A push-pull mechanism is embedded inside the extension plates. A central column is welded inside the push-pull mechanism. A baffle adjustment component is sleeved on the side of the central column. Multiple independent sound units are also embedded on the surface of the central column. The intervals between each of the independent sound units are the same, and each independent sound unit rotates around the central column. The baffle adjustment component is used to block the sound wave diffusion range of the independent sound units. Grooves are opened inside the end plates. A rotating screen is inserted inside the grooves. Volume detection components are built at both ends of the grooves. The push-pull mechanism, the baffle adjustment component, and the independent sound units are all installed on both sides of the rotating screen in a symmetric form.
[0006] Further, the push-pull mechanism includes sliding plates and push rods. Sliding grooves are opened on the inner walls of the extension plates. Positioning grooves are opened at both ends of the sliding grooves. A connecting plate is welded to one side of each sliding plate. A push rod is welded on the surface of the connecting plate.
[0007] Further, the outer sides of the sliding plates are attached to the inner walls of the extension plates. A guiding sleeve is welded in the middle of the sliding plates. A first spring is inserted inside the guiding sleeve. A ball is welded to the top end of the first spring. The entire guiding sleeve is embedded inside the sliding grooves. The ball is used to be embedded inside the positioning grooves.
[0008] Further, the baffle adjustment component includes an inner baffle, a middle baffle, and an outer baffle. Sound insulation cotton is pasted on the inner walls of the inner baffle, the middle baffle, and the outer baffle. Through holes are opened in the middle of each sound insulation cotton and in the corresponding areas of the inner baffle, the middle baffle, and the outer baffle.
[0009] Further, a fixing plate is welded on the inner wall of the end plate. A second spring is welded on the surface of the fixing plate. The end of the second spring is connected to the surface of the outer baffle. Support plates are welded at both ends of the inner walls of the inner baffle and the middle baffle. Support collar sleeves are opened at the ends of the support plates.
[0010] Further, the support collar sleeves are used to be sleeved on the surface of the central column. After the outer surface of the inner baffle rotates, it fits against the inner wall of the middle baffle. After the outer surface of the middle baffle rotates, it fits against the inner wall of the outer baffle. Both ends of the outer baffle abut against the inside of the extension plates. Both ends of the middle baffle abut against the inside of the sliding plates.
[0011] Further, the independent sound - generating unit includes a dust - proof net at the back of the speaker. A circular hole is formed in the middle of the speaker, a dust - proof net is laid on the sound - emitting holes on the surface of the speaker, and a snap ring is integrally formed on the inner wall of the circular hole.
[0012] Further, the inner - ring part of the snap ring is embedded into the surface of the central column. Rubber rings are mounted on both the top and bottom of the snap ring, and the outer sides of the rubber rings are fitted to the inner wall of the circular hole. After the independent sound - generating unit rotates, the dust - proof net is aligned with the sound - insulating cotton on the inner - layer enclosure panel.
[0013] Further, the volume - detection component includes a motor, a lead screw, and a decibel meter. The motor is screwed on the surface of the end plate, the output end of the motor is inserted with the lead screw, and the decibel meter is sleeved on the surface of the lead screw.
[0014] Further, detection bins are welded on both sides of the rotating screen. The motor is installed at the top of the detection bin. A guide rod is inserted into the interior of the detection bin. A guide sleeve ring is welded to the rear end of the decibel meter, and the guide sleeve ring is sleeved on the surface of the guide rod. The decibel meter is driven by the motor to move up and down and is used to align with the through - holes on each inner - layer enclosure panel in sequence.
[0015] Advantages of the present invention:
[0016] 1. The network new - media noise - free audio - visual device can flexibly change the sound - emitting orientation and angle of any independent sound - generating unit without moving the whole device. Each independent sound - generating unit can directly rotate on both sides of the rotating screen. Combining with the rotation effect of the rotating screen itself, the purpose of regulating the sound - emission orientation can be achieved. At the same time, by virtue of the connection form between each independent sound - generating unit and the central column, the vibration noise generated by this rotation effect is reduced, taking into account both connection flexibility and noise - reduction effect.
[0017] 2. The network new - media noise - free audio - visual device cooperates with the enclosure - regulating component to adjust the diffusion range of sound. There are a total of three sets of enclosure panels in the enclosure - regulating component. By controlling the flexible rotation of the two inner - layer enclosure panels, a reflection area can be formed in different side directions of the independent sound - generating unit, thereby achieving the purpose of adjusting the focused diffusion and large - range diffusion of sound.
[0018] 3. The network new - media noise - free audio - visual device provides the effect of hiding and storing each independent sound - generating unit, and can detect and calibrate whether the volumes of each independent sound - generating unit are consistent in the storage state, and during the calibration process, it will not have a great impact on the surrounding people due to excessive volume. Description of the Drawings
[0019] Figure 1Schematic diagram of the external structure of a noise-free audio-visual device for network new media according to the present invention;
[0020] Figure 2 Installation structure diagram of one group of sound generating units of a noise-free audio-visual device for network new media according to the present invention;
[0021] Figure 3 Installation disassembly diagram of the sound generating unit according to the present invention;
[0022] Figure 4 Top structure diagram of the push-pull mechanism according to the present invention;
[0023] Figure 5 Structure diagram of the inner side of the extension plate according to the present invention;
[0024] Figure 6 Disassembly diagram of the volume detection component part according to the present invention;
[0025] Figure 7 Disassembly diagram of the independent sound generating unit part according to the present invention;
[0026] In the figure: 1, end plate; 2, groove; 3, rotating screen; 4, extension plate; 5, push-pull mechanism; 6, enclosure adjustment component; 7, independent sound generating unit; 8, volume detection component; 9, central column; 10, middle layer enclosure; 11, inner layer enclosure; 12, sound insulation cotton; 13, through hole; 14, support plate; 15, support collar; 16, sliding plate; 17, connecting plate; 18, push-pull rod; 19, guide sleeve; 20, first spring; 21, ball; 22, outer layer enclosure; 23, second spring; 24, chute; 25, positioning groove; 26, motor; 27, detection chamber; 28, lead screw; 29, guide rod; 30, decibel meter; 31, guide collar; 32, fixing plate; 33, speaker; 34, dust-proof net; 35, round hole; 36, rubber ring; 37, snap ring. Detailed implementation manners
[0027] In order to make the technical means, creative features, achieved purposes and effects of the present invention easy to understand, the present invention will be further described below in conjunction with specific implementation manners.
[0028] Please refer to Figures 1 to 7The present invention provides the following technical solutions: a network new media noise-free audio-visual device, comprising an audio-visual device body, the audio-visual device body comprising an end plate 1, a push-pull mechanism 5, an enclosure adjustment component 6 and an independent sound unit 7, both sides of the end plate 1 are integrally formed with an extension plate 4, the inner side of the extension plate 4 is embedded with a push-pull mechanism 5, the inner side of the push-pull mechanism 5 is welded with a center column 9, the side of the center column 9 is sleeved with an enclosure adjustment component 6, the surface of the center column 9 is also embedded with a plurality of independent sound units 7, the intervals between each of the independent sound units 7 are the same, and each independent sound unit 7 rotates around the center column 9, the enclosure adjustment component 6 is used to block the sound wave diffusion range of the independent sound unit 7, a groove 2 is opened on the inner side of the end plate 1, a rotating screen 3 is inserted in the interior of the groove 2, and volume detection components 8 are built at both ends of the groove 2, the push-pull mechanism 5, the enclosure adjustment component 6 and the independent sound unit 7 are symmetrically installed on both sides of the rotating screen 3. The audio-visual device outputs images through a rotating screen 3 and outputs audio through a plurality of independent sound-emitting units 7 at both ends.
[0029] When the present invention is in use, the top and bottom end plates 1 provide support for the inner rotating screen 3 so that the rotating screen 3 can rotate around the middle axis, and enclosure adjustment components 6, push-pull mechanisms 5 and multiple independent sound units 7 are provided on both sides of the end plate 1, and each independent sound unit 7 is installed on the central column 9, so that each independent sound unit 7 can also rotate around the central column 9, and an enclosure adjustment component 6 is provided on the outside of the independent sound unit 7. The enclosure area around the independent sound unit 7 is changed by the enclosure adjustment component 6, so as to adjust the reflection range of the sound wave, so that the sound wave generated by the independent sound unit 7 can be concentrated and propagated toward a set side, so as to achieve the purpose of controlling the sound to the diffusion range or diffusion direction, and at the same time, with the help of the volume detection components 8 provided at both ends of the end plate 1, each independent sound unit 7 is provided with a storage shield, and the purpose of volume detection and calibration can be achieved during the storage process.
[0030] In this embodiment, the push-pull mechanism 5 includes a sliding plate 16 and a push-pull rod 18. A sliding groove 24 is provided on the inner wall of the extension plate 4. Positioning grooves 25 are provided at both ends of the sliding groove 24. A connecting plate 17 is welded to one side of each sliding plate 16. A push-pull rod 18 is welded to the surface of the connecting plate 17. The outer side of the sliding plate 16 is fitted with the inner wall of the extension plate 4. A guide sleeve 19 is welded to the middle of the sliding plate 16. A first spring 20 is inserted into the guide sleeve 19. A ball 21 is welded to the top of the first spring 20. The guide sleeve 19 is integrally embedded in the sliding groove 24. The ball 21 is used to be embedded in the positioning groove 25.
[0031] Specifically, by manually controlling the push-pull rod 18 to drive the sliding plates 16 at the top and bottom to move along the inner wall of the extension plate 4, the translation movement of the entire central column 9 can be controlled. Since the independent sound units 7 and the enclosure adjustment mechanism are both installed relying on the central column 9, the positions of each independent sound unit 7 inside can be controlled through the push-pull mechanism 5. During this adjustment process, the guide sleeve 19 on the outer side of the sliding plate 16 is inserted into the inside of the chute 24, and after the ball 21 at the end of the first spring 20 is inserted into the positioning groove 25, the positioning purpose of the entire push-pull mechanism 5 and the central column 9 can be achieved. Therefore, after moving the ball 21 to the outer positioning groove 25 through the push-pull mechanism 5, each independent sound unit 7 can be pulled out for use. When moving the ball 21 into the inner positioning groove 25, each independent sound unit 7 and the enclosure adjustment component 6 can be directly abutted against the inside of the detection bin 27 for hiding treatment.
[0032] In this embodiment, the enclosure adjustment component 6 includes an inner enclosure plate 11, a middle enclosure plate 10, and an outer enclosure plate 22. Sound insulation cotton 12 is attached to the inner walls of the inner enclosure plate 11, the middle enclosure plate 10, and the outer enclosure plate 22, and through holes 13 are provided in the middle of each sound insulation cotton 12 and in the corresponding areas of the inner enclosure plate 11, the middle enclosure plate 10, and the outer enclosure plate 22. A fixing plate 32 is welded to the inner wall of the end plate 1, a second spring 23 is welded to the surface of the fixing plate 32, and the end of the second spring 23 is connected to the surface of the outer enclosure plate 22. Support plates 14 are welded to both ends of the inner walls of the inner enclosure plate 11 and the middle enclosure plate 10, and support sleeve rings 15 are provided at the ends of the support plates 14. The support sleeve rings 15 are used to sleeved on the surface of the central column 9, and after the outer surface of the inner enclosure plate 11 rotates, it fits against the inner wall of the middle enclosure plate 10. After the outer surface of the middle enclosure plate 10 rotates, it fits against the inner wall of the outer enclosure plate 22. Both ends of the outer enclosure plate 22 abut against the inside of the extension plate 4, and both ends of the middle enclosure plate 10 abut against the inside of the sliding plate 16. Cooperating with the enclosure adjustment component 6 to adjust the diffusion range of sound, the enclosure adjustment component 6 has a total of three groups of enclosure plates. By controlling the flexible rotation of the two inner enclosure plates, reflection areas can be formed in different side directions of the independent sound unit 7, thereby achieving the adjustment purpose of sound concentration diffusion and large-range diffusion.
[0033] Specifically, by manually controlling the rotation of the middle enclosure plate 10 to the outside and the rotation of the inner enclosure plate 11 to the rear, at this time, as Figure 1 and 2 shown, cooperating with the outer enclosure plate 22, it can be achieved in Figure 1In this case, arc-shaped reflectors are formed at the rear and both sides of each independent sound-emitting unit 7 to ensure that the emitted sound is mainly diffused forward. Similarly, by controlling the inner enclosure 11 to rotate forward, the sound can be mainly diffused and emitted toward the opened rear. If the middle enclosure 10 is rotated to fit with the outer enclosure 22, and the inner enclosure 11 is also rotated to fit with the inner enclosure 11, the sound emitted by the independent sound-emitting unit 7 can be directly diffused toward the front, rear, and sides, thereby achieving the purpose of regulating the diffusion angle.
[0034] In this embodiment, the independent sound-emitting unit 7 includes a rear dust-proof net 34 of the speaker 33. A round hole 35 is formed in the middle of the speaker 33. A dust-proof net 34 is laid on the sound-emitting holes on the surface of the speaker 33. A snap ring 37 is integrally formed on the inner wall of the round hole 35. The inner ring part of the snap ring 37 is embedded in the surface of the central column 9. Rubber rings 36 are attached to both the top and bottom of the snap ring 37. The outer sides of the rubber rings 36 are in contact with the inner wall of the round hole 35. After the independent sound-emitting unit 7 rotates, the dust-proof net 34 is aligned and fitted with the sound-insulating cotton 12 on the inner enclosure 11. It is possible to flexibly change the sound-emitting direction and angle of any independent sound-emitting unit 7 without moving the entire device as a whole. Each independent sound-emitting unit 7 can directly rotate on both sides of the rotating screen 3. Combining with the rotation effect of the rotating screen 3 itself, the purpose of regulating the sound-emitting direction can be achieved. At the same time, by virtue of the connection form between each independent sound-emitting unit 7 and the central column 9, the vibration noise generated by this rotation effect is reduced, taking into account both connection flexibility and noise reduction effects. Specifically, each independent sound-emitting unit 7 is movably connected to the surface of the central column 9 through the inner snap ring 37. Therefore, each independent sound-emitting unit 7 can be directly manually controlled to rotate along the central column 9 to achieve the purpose of regulating the angle of the independent sound-emitting unit 7. At the same time, the rubber rings 36 at the top and bottom can also squeeze the snap ring 37 part to avoid the problem of large vibration noise generated between the snap ring 37 as a movable part and the central column 9 during the subsequent use of the independent sound-emitting unit 7.
[0035] In this embodiment, the volume detection component 8 includes a motor 26, a lead screw 28, and a decibel meter 30. The motor 26 is screwed to the surface of the end plate 1. The output end of the motor 26 is inserted with the lead screw 28, and the decibel meter 30 is sleeved on the surface of the lead screw 28. Both sides of the rotating screen 3 are welded with detection bins 27. The motor 26 is installed at the top of the detection bin 27. A guide rod 29 is inserted into the detection bin 27. A guide collar 31 is welded to the rear end of the decibel meter 30, and the guide collar 31 is sleeved on the surface of the guide rod 29. The decibel meter 30 is driven by the motor 26 to move up and down, and is used to align with the through holes 13 on each inner layer enclosure 11 in sequence. It provides the effect of hiding and storing each independent sound generating unit 7, and can detect and calibrate whether the volumes of each independent sound generating unit 7 are consistent in the storage state, and during the calibration process, it will not have a great impact on the surrounding personnel due to excessive volume.
[0036] Specifically, through the above-mentioned regulation process of the enclosure adjustment component 6, after the inner layer enclosures 11, the middle layer enclosures 10, and the outer layer enclosures 22 are fitted in sequence, then control each independent sound generating unit 7 to rotate until the sound outlet holes inside the dust-proof net 34 are aligned with the sound insulation cotton 12, and then control the decibel meter 30 to move along the lead screw 28 through the motor 26 in sequence, and align it with the through hole 13 from the inside of the detection bin 27. Start each independent sound generating unit 7 to emit a fixed sound in sequence, and the purpose of detecting the volume of the independent sound generating unit 7 can be achieved through the decibel meter 30. And due to the use of the sound insulation cotton 12, even if the independent sound generating unit 7 is controlled to emit a large volume, the volume can still be limited only through the small through hole 13, reducing the noise pollution to the external environment during the detection process.
[0037] The above shows and describes the basic principles, main features, and advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic features of the present invention.
[0038] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A network new media noiseless audio-visual device, comprising an audio-visual device body, characterized in that: The audio-visual device body comprises an end plate (1), a push-pull mechanism (5), a fence adjustment assembly (6) and an independent sound-emitting unit (7). Extension plates (4) are integrally formed on both sides of the end plate (1). The push-pull mechanism (5) is embedded in the inner side of the extension plate (4). A central column (9) is welded on the inner side of the push-pull mechanism (5). The side of the central column (9) is sleeved with the fence adjustment assembly (6). A plurality of independent sound-emitting units (7) are also embedded on the surface of the central column (9). The spacing between each of the independent sound-emitting units (7) is 1 / 4. The spacing is the same, and each independent sound unit (7) rotates around the central column (9), the enclosure adjustment component (6) is used to block the sound wave diffusion range of the independent sound unit (7), the inner side of the end plate (1) is provided with a groove (2), the interior of the groove (2) is inserted with a rotating screen (3), and both ends of the groove (2) are built with volume detection components (8), and the push-pull mechanism (5), the enclosure adjustment component (6) and the independent sound unit (7) are symmetrically installed on both sides of the rotating screen (3).
2. A network new media noiseless audio-visual device according to claim 1, characterized in that: The push-pull mechanism (5) comprises a sliding plate (16) and a push-pull rod (18); a sliding groove (24) is provided on the inner wall of the extension plate (4); positioning grooves (25) are provided at both ends of the sliding groove (24); a connecting plate (17) is welded to one side of each sliding plate (16); and a push-pull rod (18) is welded to the surface of the connecting plate (17).
3. A network new media noiseless audio-visual device according to claim 2, characterized in that: The outer side of the sliding plate (16) is fitted with the inner wall of the extension plate (4); a guide sleeve (19) is welded in the middle of the sliding plate (16); a first spring (20) is inserted into the interior of the guide sleeve (19); a ball (21) is welded to the top of the first spring (20); the guide sleeve (19) is integrally embedded in the interior of the slide groove (24); and the ball (21) is used to be embedded in the interior of the positioning groove (25).
4. The network new media noiseless audio-visual device according to claim 2, characterized in that: The enclosure adjustment assembly (6) comprises an inner enclosure (11), a middle enclosure (10) and an outer enclosure (22), and the inner walls of the inner enclosure (11), the middle enclosure (10) and the outer enclosure (22) are all mounted with sound insulation cotton (12), and a through hole (13) is opened in the middle of each sound insulation cotton (12) and in the corresponding inner enclosure (11), middle enclosure (10) and outer enclosure (22) areas.
5. The network new media noiseless audio-visual device according to claim 4, characterized in that: A fixing plate (32) is welded on the inner wall of the end plate (1), a second spring (23) is welded on the surface of the fixing plate (32), the end of the second spring (23) is connected to the surface of the outer layer enclosure (22), and support plates (14) are welded at both ends of the inner walls of the inner layer enclosure (11) and the middle layer enclosure (10), and a support collar (15) is provided at the end of the support plate (14).
6. A network new media noiseless audio-visual device according to claim 5, characterized in that: The support collar (15) is used to be sleeved on the surface of the central column (9), and the outer surface of the inner panel (11) is rotated to fit with the inner wall of the middle panel (10), and the outer surface of the middle panel (10) is rotated to fit with the inner wall of the outer panel (22), and the two ends of the outer panel (22) are against the inner side of the extension plate (4), and the two ends of the middle panel (10) are against the inner side of the sliding plate (16).
7. The network new media noiseless audio-visual device according to claim 4, characterized in that: The independent sound-emitting unit (7) comprises a dust-proof net (34) behind the speaker (33), a circular hole (35) is provided in the middle of the speaker (33), a dust-proof net (34) is laid on the sound outlet hole on the surface of the speaker (33), and a clamping ring (37) is integrally formed on the inner wall of the circular hole (35).
8. The network new media noiseless audio-visual device according to claim 7, characterized in that: The inner ring of the snap ring (37) is embedded in the surface of the center column (9), and rubber rings (36) are attached to the top and bottom of the snap ring (37). The outer side of the rubber ring (36) fits with the inner wall of the circular hole (35). After the independent sound unit (7) is rotated, the dustproof net (34) is aligned with the sound insulation cotton (12) on the inner panel (11).
9. The network new media noiseless audio-visual device according to claim 7, characterized in that: The volume detection assembly (8) comprises a motor (26), a screw rod (28) and a decibel meter (30); the motor (26) is screwed onto the surface of the end plate (1); the output end of the motor (26) is plugged with the screw rod (28); and the decibel meter (30) is sleeved on the surface of the screw rod (28).
10. A network new media noiseless audio-visual device according to claim 9, characterized in that: Detection chambers (27) are welded on both sides of the rotating screen (3), the motor (26) is installed at the top of the detection chamber (27), a guide rod (29) is inserted inside the detection chamber (27), a guide ring (31) is welded at the rear end of the decibel meter (30), and the guide ring (31) is sleeved on the surface of the guide rod (29), the decibel meter (30) is driven by the motor (26) to move up and down, and is used to align with the through hole (13) on each inner layer enclosure (11) in turn.