Sound absorbing structure and sound absorbing device
By setting through holes, electromagnetic structures of conductive bodies and magnetic parts on the insulating substrate, the problem of narrow frequency bands of traditional thin film resonant sound absorption structures is solved, and a wider sound absorption effect is achieved, significantly improving the sound absorption ability.
Patent Information
- Application Number
- CN202111575471.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-12-21
- Publication Date
- 2024-12-24
- Estimated Expiration
- 2041-12-21
AI Technical Summary
The sound absorption frequency band of the traditional thin film resonant sound absorption structure is narrow and has good sound absorption performance only near the resonant frequency. The resonant frequency is determined by the film density, tension and the depth of the closed cavity, making it difficult to adjust, which limits its practical application.
A sound absorbing structure is designed, including an insulating substrate, a first insulating film body, a first magnetic member and a conductor. By providing a through hole on the insulating substrate, the electromagnetic action of the conductor and the magnetic member is used to generate an annular induced current and The magnetic field and damping effect consume the sound wave energy and broaden the sound absorption frequency band.
By introducing electromagnetic effects, the sound absorption capacity is significantly improved, the resonance frequency limitation is freed, and a wider sound absorption effect is achieved.
Smart Images
Figure CN114170993B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of mufflers, and in particular relates to a sound absorbing structure and a sound absorbing device. Background Art
[0002] Thin film resonance sound absorption structure is widely used in noise reduction devices. Traditional thin film resonance sound absorption structure usually attaches the film to the opening of the closed cavity, so that the film and the air in the closed cavity form a resonance system. When the frequency of the incident sound wave is equal to the resonance frequency of the system, resonance occurs. At this time, the incident sound wave excites the film to vibrate, and the vibration will cause the loss of sound wave energy, thereby achieving the purpose of sound absorption.
[0003] However, the sound absorption band of this structure is narrow, and it has good sound absorption performance only near the resonance frequency. The resonance frequency of this structure is determined by the density and tension of the film and the depth of the closed cavity. If you want to adjust its sound absorption band, you need to replace the film or change the depth of the closed cavity. This is very inconvenient, and in practical applications, it is usually limited by the space in the equipment and cannot be adjusted, which limits the practical application of this sound absorption structure. Summary of the invention
[0004] In order to overcome the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a sound absorbing structure, aiming to solve the technical problems that the existing thin film resonance sound absorbing structure has large application limitations and poor sound absorption effect.
[0005] In order to achieve the purpose, the technical solution adopted by the present invention is as follows:
[0006] A sound absorbing structure, comprising an insulating substrate, a first insulating film, a first magnetic member and a conductor; wherein:
[0007] A through hole is provided on the insulating substrate, the first insulating film body is attached to one side surface of the insulating substrate, the first insulating film body is partially suspended in the through hole, the first magnetic member is fixed on the first insulating film body and is located in the through hole, the conductor is fixed on one side surface of the insulating substrate facing away from the first insulating film body, and the conductor is in a closed ring shape and surrounds the through hole.
[0008] Furthermore, the sound absorbing structure further includes a second insulating film and a second magnetic member; wherein:
[0009] The second insulating film body is spaced apart from the conductor, and one side surface of the second insulating film body is opposite to a side of the conductor facing away from the insulating substrate, and the second magnetic member is fixed on a side surface of the second insulating film body facing away from the conductor.
[0010] Furthermore, the sound absorbing structure further comprises a fixing frame, and an edge of the second insulating film body is connected to an inner side wall of the fixing frame.
[0011] Furthermore, the edge of the insulating substrate is connected to the inner wall of the fixing frame.
[0012] Furthermore, a magnetization direction of the first magnetic member is parallel to an axial direction of the conductor.
[0013] Furthermore, a magnetization direction of the second magnetic member is parallel to an axial direction of the conductor.
[0014] Furthermore, the second magnetic member is in sheet shape and covers the inner ring of the conductor.
[0015] Furthermore, the thickness of the second insulating film body is greater than the thickness of the first insulating film body.
[0016] Furthermore, the material of the first magnetic component is any one of neodymium iron boron, samarium cobalt, and aluminum nickel cobalt.
[0017] Furthermore, the material of the second magnetic component is any one of neodymium iron boron, samarium cobalt, and aluminum nickel cobalt.
[0018] Furthermore, the insulating substrate is made of any one of polyimide, polyetheretherketone, polyetherimide, and polyethylene naphthalate.
[0019] Furthermore, the conductor is made of any one of copper and soft iron.
[0020] Furthermore, there are a plurality of through holes, and there are a plurality of the first magnetic member and the conductor, which correspond to the through holes one by one.
[0021] Correspondingly, the present invention also provides a sound absorbing device, which includes the sound absorbing structure as described above.
[0022] Compared with the prior art, the present invention has the following beneficial effects:
[0023] The sound absorption structure proposed in the present invention is that a conductor and a first magnetic member that vibrates with the first insulating film are respectively arranged on both sides of an insulating substrate with a through hole. When the sound wave energy of external noise causes the suspended part of the first insulating film in the through hole to vibrate, the first magnetic member will be driven to move back and forth in the through hole relative to the conductor to cut the magnetic flux lines, thereby generating a circular induced current on the conductor, which will generate a new magnetic field. According to Lenz's law, the new magnetic field always opposes the movement of the first magnetic member. The damping effect formed by this opposition will consume the sound wave energy of the external noise and achieve a sound absorption effect. This sound absorption method introduces the effect of electromagnetics. Compared with the traditional structure that only relies on film resonance to consume sound energy, it is no longer limited by the resonance frequency, and the sound absorption capacity is significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.
[0025] Figure 1 It is a schematic cross-sectional structure diagram of an embodiment of a sound absorbing structure of the present invention;
[0026] Figure 2 It is a schematic cross-sectional structure diagram of another embodiment of the sound absorbing structure of the present invention;
[0027] Figure 3 It is a schematic diagram of the exploded structure of another embodiment of the sound absorbing structure of the present invention.
[0028] Description of reference numerals:
[0029] Label name Label name 1 Insulation substrate 5 Second insulating film 2 First insulating film 6 The second magnetic member 3 The first magnetic element 7 Fixed frame 4 Conductor 11 Through Hole
[0030] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION
[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0032] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.
[0033] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.
[0034] Reference Figure 1 An embodiment of the present invention provides a sound absorbing structure, which includes an insulating substrate 1, a first insulating film 2, a first magnetic member 3 and a conductor 4; wherein:
[0035] A through hole 11 is provided on the insulating substrate 1, the first insulating film body 2 is attached to one side surface of the insulating substrate 1, the part of the first insulating film body 2 in the through hole 11 is suspended, the first magnetic member 3 is fixed on the first insulating film body 2 and is located in the through hole 11, and the conductor 4 is fixed on the side surface of the insulating substrate 1 which is away from the first insulating film body 2, and the conductor 4 is in a closed ring shape and surrounds the through hole 11.
[0036] In this embodiment, the first insulating film 2 is a film with a preset tension. Specifically, the first insulating film 2 can be stretched by a film stretching tool and then attached to the insulating substrate 1, and the specific tension can be adjusted by measuring the relationship between the resonance frequency and tension of the first insulating film 2. Illustrated, the through hole 11 can be a circular hole, the first magnetic member 3 can be cylindrical and arranged at the center of the circular hole, and the conductor 4 can be annular; preferably, the inner diameter of the conductor 4 is equal to the aperture of the through hole 11, and the conductor 4 and the through hole 11 are coaxially matched.
[0037] When there is noise in the outside world, the sound wave energy of the noise will cause the suspended part of the first insulating film body 2 located in the through hole 11 to vibrate, thereby driving the first magnetic part 3 to reciprocate relative to the conductor 4 in the through hole 11. The reciprocating movement is equivalent to the conductor 4 cutting the magnetic flux lines. As a result, an induced current will be generated on the conductor 4 due to electromagnetic induction. The direction of the induced current is clockwise or counterclockwise around the conductor 4; and the circular induced current will generate a new magnetic field (the new magnetic field mentioned in the following description refers to this magnetic field). According to Lenz's law, the magnetic field of the induced current will always hinder the change of the magnetic flux causing the induced current. Therefore, the new magnetic field will always oppose the movement of the first magnetic part 3. The damping effect formed by this confrontation will consume the sound wave energy and achieve the effect of sound absorption.
[0038] It can be seen that the sound absorption structure provided in this embodiment is provided with a conductor 4 and a first magnetic member 3 that vibrates with the first insulating film body 2 on both sides of the insulating substrate 1 with a through hole 11. When the sound wave energy of the external noise causes the suspended part of the first insulating film body 2 located in the through hole 11 to vibrate, it will drive the first magnetic member 3 to move back and forth in the through hole 11 relative to the conductor 4 to cut the magnetic flux line, thereby generating a circular induced current on the conductor 4, and the circular induced current will generate a new magnetic field. According to Lenz's law, the new magnetic field always opposes the movement of the first magnetic member 3. The damping effect formed by this opposition will consume the sound wave energy of the external noise and achieve the sound absorption effect. This sound absorption method introduces the effect of electromagnetics. Compared with the traditional structure that only relies on film resonance to consume sound energy, it is no longer limited by the resonance frequency, and the sound absorption capacity is significantly improved.
[0039] Further, refer to Figure 1 In an exemplary embodiment, the sound absorbing structure further includes a second insulating film 5 and a second magnetic member 6; wherein:
[0040] The second insulating film 5 is spaced apart from the conductor 4 , and one side of the second insulating film 5 is opposite to the side of the conductor 4 facing away from the insulating substrate 1 . The second magnetic member 6 is fixed on the side of the second insulating film 5 facing away from the conductor 4 .
[0041] In this embodiment, the second insulating film body 5 can be tensioned in the same manner as the first insulating film body 2 and its edge can be fixed on the support seat. Illustrated, the second insulating film body 5 can be located below the insulating substrate 1 and opposite to the conductor 4, and the second magnetic member 6 can be located directly below the conductor 4. When the circular induced current on the conductor 4 generates a new magnetic field, the new magnetic field will interact with the second magnetic member 6 below, so that the second magnetic member 6 drives the second insulating film body 5 to reciprocate (or vibrate), thereby further consuming the sound wave energy of the external noise and enhancing the sound absorption effect.
[0042] Further, refer to Figure 2 In an exemplary embodiment, the sound absorbing structure further includes a fixing frame 7 , and an edge of the second insulating film body 5 is connected to an inner side wall of the fixing frame 7 .
[0043] Specifically, refer to Figure 2 The edge of the insulating substrate 1 is connected to the inner wall of the fixing frame 7 .
[0044] Illustratively, through the connection of the fixing frame 7 , the insulating substrate 1 , the first insulating film 2 , the first magnetic member 3 , the conductor 4 , the second insulating film 5 and the second magnetic member 6 form a complete sound absorbing unit.
[0045] Specifically, the magnetization direction of the first magnetic member 3 and the axial direction of the conductor 4 are parallel to each other.
[0046] Specifically, the magnetization direction of the second magnetic member 6 is parallel to the axial direction of the conductor 4 .
[0047] When the magnetization directions of the first magnetic component 3 and the second magnetic component 6 are parallel to the axial direction of the conductor 4, if the first magnetic component 3 moves back and forth along the axial direction of the conductor 4 under the vibration of the first insulating film 2, the damping effect generated between the new magnetic field and the first magnetic component 3 and the second magnetic component 6 will be maximized, and the sound wave energy of the external noise can be consumed to the greatest extent at this time.
[0048] Specifically, refer to Figure 1 and Figure 2 The second magnetic member 6 is in sheet shape and covers the inner ring of the conductor 4 .
[0049] When the second magnetic member 6 is in the form of a thin sheet and covers the inner ring of the conductor 4 (covering here means that the inner ring of the conductor 4 is completely within the range covered by the second magnetic member 6 when viewed from the vertical direction of the diagram), the force generated by the new magnetic field will cause the second magnetic member 6 itself to deform to a certain extent, and this deformation can further consume the sound wave energy of the external noise. Preferably, the second magnetic member 6 is circular and its center is located on the central axis of the conductor 4, so that the force-bearing area of the second magnetic member 6 (i.e., the force generated by the new magnetic field) can be maximized.
[0050] Specifically, the thickness of the second insulating film body 5 is greater than the thickness of the first insulating film body 2 .
[0051] The greater the thickness of the film, the better the performance of absorbing low-frequency sound waves. Through the cooperation between the first insulating film 2 and the second insulating film 5, the sound absorption frequency band of the sound absorption structure can be broadened.
[0052] Specifically, the material of the first magnetic component 3 is any one of neodymium iron boron, samarium cobalt, and aluminum nickel cobalt.
[0053] Specifically, the material of the second magnetic component 6 is any one of neodymium iron boron, samarium cobalt, and aluminum nickel cobalt.
[0054] Specifically, the conductor 4 is made of copper or soft iron.
[0055] Specifically, the material of the insulating substrate 1 is any one of polyimide, polyetheretherketone, polyetherimide, and polyethylene naphthalate.
[0056] Polyimide, polyetheretherketone (PEEK), polyetherimide, and polyethylene naphthalate (PEN) are all polymer materials, and all have the characteristics of high temperature resistance and good acoustic performance. They can be selected according to needs in practical applications. Specifically, they can be made into films first, and then the multi-layer films can be bonded into a composite film by gluing, and finally made into an insulating substrate 1, which can improve the acoustic performance.
[0057] Further, refer to Figure 2 and Figure 3 In an exemplary embodiment, there are multiple through holes 11 , and there are multiple first magnetic members 3 and multiple conductors 4 , which correspond to the through holes 11 one by one.
[0058] like Figure 3 As shown, a plurality of first magnetic members 3 and conductors 4 form an array of a plurality of muffler units on the insulating substrate 1, which can greatly improve the muffler effect. Preferably, the second magnetic members 6 can also be arranged in a corresponding plurality as shown in the figure.
[0059] Correspondingly, an embodiment of the present invention further provides a sound absorbing device, which includes the sound absorbing structure in any of the above embodiments.
[0060] In this embodiment, the sound absorbing device can be a muffler applied to a soundproof wall, an audio device, or a machine that generates a large amount of noise during operation. Since the sound absorbing device adopts all the technical solutions of all the embodiments of the above-mentioned sound absorbing structure, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.
[0061] It should be noted that other contents of the sound absorbing structure and the sound absorbing device disclosed in the present invention can be found in the prior art and will not be described in detail here.
[0062] The above are only optional embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.
Claims
1. A sound absorbing structure, characterized in that: The sound absorbing structure comprises an insulating substrate, a first insulating film, a first magnetic member, a conductor, a second insulating film and a second magnetic member; wherein: The insulating substrate is provided with a through hole, the first insulating film body is attached to one side of the insulating substrate, the first insulating film body is partially suspended in the through hole, the first magnetic member is fixed on the first insulating film body and is located in the through hole, the conductor is fixed on one side of the insulating substrate facing away from the first insulating film body, the conductor is in a closed ring shape and surrounds the through hole; The second insulating film body is spaced apart from the conductor, and one side surface of the second insulating film body is opposite to a side of the conductor facing away from the insulating substrate, and the second magnetic member is fixed on a side surface of the second insulating film body facing away from the conductor.
2. The sound absorbing structure according to claim 1, characterized in that: The sound absorbing structure further comprises a fixing frame, and the edge of the second insulating film body is connected to the inner side wall of the fixing frame; And / or, the edge of the insulating substrate is connected to the inner wall of the fixing frame.
3. The sound absorbing structure according to claim 1, characterized in that: The magnetization direction of the first magnetic member is parallel to the axial direction of the conductor; And / or, the magnetization direction of the second magnetic member is parallel to the axial direction of the conductor.
4. The sound absorbing structure according to claim 1, characterized in that: The second magnetic member is in sheet shape and covers the inner ring of the conductor.
5. The sound absorbing structure according to claim 1, characterized in that: The thickness of the second insulating film body is greater than the thickness of the first insulating film body.
6. The sound absorbing structure according to claim 1, characterized in that: The material of the second magnetic component is any one of neodymium iron boron, samarium cobalt, and aluminum nickel cobalt.
7. The sound absorbing structure according to any one of claims 1 to 6, characterized in that: There are a plurality of through holes, and there are a plurality of the first magnetic member and the conductor, which correspond to the through holes one by one.
8. The sound absorbing structure according to any one of claims 1 to 6, characterized in that: The insulating substrate is made of any one of polyimide, polyetheretherketone, polyetherimide and polyethylene naphthalate; The material of the first magnetic component is any one of neodymium iron boron, samarium cobalt, and aluminum nickel cobalt; The material of the conductor is any one of copper and soft iron.
9. A sound absorbing device, characterized in that: The sound absorbing device comprises the sound absorbing structure according to any one of claims 1 to 8.