Noise reduction mechanism and sound box

Abstract

The embodiment of the application provides a kind of noise reduction mechanism and sound box, it is related to acoustic equipment technical field.The noise reduction mechanism includes: inverting phase pipe, inverting phase pipe is used to be arranged in the box body of sound box, one end of inverting phase pipe is used to be connected with the inner wall of box body, and the other end of inverting phase pipe is used to extend to the inside of box body;Internal shaft, internal shaft is arranged in the inside of inverting phase pipe, and the outer peripheral wall of internal shaft and the inner peripheral wall of inverting phase pipe form airflow spacing between them.The noise reduction mechanism and sound box can reduce the maximum flow rate and average flow rate of the airflow in the inverting phase pipe, weaken the disturbance generated by airflow and pipe wall, airflow mutual friction, and then reduce the airflow noise generated by airflow disturbance, improve the overall playback sound quality of sound box.

Description

Technical Field

[0001] This application relates to the field of acoustic equipment technology, and in particular to a noise reduction mechanism and a speaker. Background Technology

[0002] A speaker is a device that converts electrical signals into sound. It is widely used in home entertainment, professional audio-visual systems, public address systems, and performance systems. The function of a speaker is to provide high-quality sound playback for various application scenarios.

[0003] In related technologies, a speaker enclosure includes a cabinet, a loudspeaker, and a bass reflex port. The loudspeaker is connected to the cabinet, one end of the bass reflex port passes through the cabinet and communicates with the outside of the cabinet, and the other end of the bass reflex port extends into the inside of the cabinet. By rationally designing the dimensions of the cabinet and the bass reflex port, the sound waves radiated from the bass reflex port and the sound waves radiated from the front of the loudspeaker diaphragm are superimposed in phase at low frequencies, thereby enhancing the bass output.

[0004] However, when the speaker is working, the vibration of the speaker pushes or draws the air inside the cabinet, which in turn causes high-speed airflow inside the bass reflex port. The airflow noise generated by the high-speed airflow seriously affects the sound quality of the speaker. Summary of the Invention

[0005] This application provides a noise reduction mechanism and a speaker to reduce the maximum and average flow velocity of the airflow inside the bass reflex tube, weaken the disturbance caused by the friction between the airflow and the tube wall, thereby reducing the airflow noise generated by the airflow disturbance and improving the overall sound quality of the speaker.

[0006] In a first aspect, embodiments of this application provide a noise reduction mechanism, including:

[0007] A bass reflex tube is used to be installed inside the speaker cabinet. One end of the bass reflex tube is used to connect to the inner wall of the cabinet, and the other end of the bass reflex tube is used to extend into the interior of the cabinet.

[0008] An internal shaft is disposed inside the phase inverter tube, and an airflow gap is formed between the outer peripheral wall of the internal shaft and the inner peripheral wall of the phase inverter tube.

[0009] In some embodiments, one end of the internal shaft is used to connect to the inner wall of the enclosure or the speaker of the speaker enclosure, and the other end of the internal shaft extends toward the interior of the bass reflex tube.

[0010] In some embodiments, the system further includes a support for connecting to the outer wall of the housing, one end of the internal shaft for connecting to the inner wall of the housing, and the other end of the internal shaft for connecting to the support.

[0011] In some embodiments, at least one support rod is further included, one end of which is connected to the outer wall of the inner shaft, and the other end of which is connected to the inner wall of the phase inverter tube.

[0012] In some embodiments, the system further includes an outer support and an inner support. The outer support is used to connect to the outer wall of the housing, and the inner support is used to connect to the outer wall of the phase inverter tube. One end of the inner shaft is connected to the outer support, and the other end of the inner shaft is connected to the inner support.

[0013] In some embodiments, the two ends of the phase inverter are configured as flared openings, the internal shaft includes a connecting portion and a variable diameter portion, both ends of the connecting portion are provided with the variable diameter portion, and the cross-sectional area of ​​the variable diameter portion gradually decreases along the direction away from the connecting portion.

[0014] In some embodiments, a plurality of protrusions are provided on the outer wall of the inner shaft;

[0015] Alternatively, multiple grooves may be provided on the outer wall of the inner shaft;

[0016] Alternatively, a spiral groove may be provided on the outer wall of the inner shaft;

[0017] Alternatively, the outer wall of the inner shaft has at least one first groove, which is arranged along the axial direction of the inner shaft;

[0018] Alternatively, a plurality of second grooves are provided on the outer wall of the inner shaft, each of the second grooves being arranged circumferentially along the outer wall of the inner shaft.

[0019] In some embodiments, the device further includes a sound-absorbing element, wherein the interior of the inner shaft is provided with a cavity, and the inner shaft is provided with a plurality of through holes, the through holes connecting the cavity and the airflow gap, and the sound-absorbing element fills the interior of the cavity.

[0020] In some embodiments, a closure is further included, which is disposed along the axial direction of the inner shaft, with at least one end of the cavity extending through the inner shaft. The closure is used to engage or disengage with an end of the cavity to close or open the cavity.

[0021] In some embodiments, at least a portion of the internal shaft is configured as a foam metal shaft.

[0022] Secondly, this application provides a speaker, including a cabinet and the aforementioned noise reduction mechanism. The bass reflex tube of the noise reduction mechanism is disposed inside the cabinet, one end of the bass reflex tube is connected to the inner wall of the cabinet, and the other end of the bass reflex tube extends into the interior of the cabinet.

[0023] This application provides a noise reduction mechanism and a speaker enclosure. In the noise reduction mechanism provided, the speaker diaphragm reciprocates during operation, pushing and drawing air from inside the enclosure. This causes periodic changes in the internal air pressure, creating a pressure difference with the outside of the enclosure. Air travels back and forth through the bass reflex tube due to this pressure difference. After entering the bass reflex tube, the airflow is split into an annular airflow gap formed by the inner circumferential wall of the bass reflex tube and the outer circumferential wall of the internal shaft. The airflow flows in layers along the inner and outer walls of the airflow gap. The high-speed airflow originally concentrated in the center of the bass reflex tube is dispersed and split by the internal shaft, resulting in a more uniform airflow path. The internal shaft located inside the bass reflex tube, combined with the annular airflow gap, can effectively disperse the original high-speed airflow. By concentrating the airflow stream and altering the single flow channel structure, the maximum and average airflow velocities inside the bass reflex tube are reduced. This decrease in airflow velocity reduces turbulence intensity during airflow, weakens disturbances caused by friction between the airflow and the tube wall, and further reduces airflow noise. This optimizes the airflow state inside the bass reflex tube, reduces the probability of eddies caused by sudden airflow changes, and decreases the proportion of unwanted noise in the low-frequency range of the speaker. The purity of low-frequency sound waves is improved, and the superposition effect of low-frequency sound waves radiated from the front of the speaker diaphragm and low-frequency sound waves output from the bass reflex tube is more stable, resulting in a certain degree of improvement in the overall sound quality of the speaker. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0025] Figure 1 A structural schematic diagram of the noise reduction mechanism in its assembled state provided in this application;

[0026] Figure 2 A cross-sectional structural diagram of the noise reduction mechanism in its assembled state provided in this application;

[0027] Figure 3 Schematic diagram of the support structure for the noise reduction mechanism provided in this application Figure 1 ;

[0028] Figure 4 Schematic diagram of the support structure for the noise reduction mechanism provided in this application Figure 2 ;

[0029] Figure 5 A cross-sectional structural diagram showing the connection between the internal shaft of the noise reduction mechanism provided in this application and the speaker;

[0030] Figure 6 A schematic diagram of the support rod of the noise reduction mechanism provided in this application;

[0031] Figure 7 A schematic diagram of the outer and inner supports of the noise reduction mechanism provided in this application;

[0032] Figure 8 A schematic diagram of the connecting part and the variable diameter part of the noise reduction mechanism provided in this application;

[0033] Figure 9 A schematic diagram of the internal shaft and protrusions of the noise reduction mechanism provided in this application;

[0034] Figure 10 A schematic diagram of the internal shaft and groove of the noise reduction mechanism provided in this application;

[0035] Figure 11 A schematic diagram of the internal shaft and spiral groove of the noise reduction mechanism provided in this application;

[0036] Figure 12 A schematic diagram of the internal shaft and the first groove of the noise reduction mechanism provided in this application;

[0037] Figure 13 Schematic diagram of the internal shaft and second groove of the noise reduction mechanism provided in this application Figure 1 ;

[0038] Figure 14 Schematic diagram of the internal shaft and second groove of the noise reduction mechanism provided in this application Figure 2 ;

[0039] Figure 15 A schematic diagram of the internal shaft and cavity of the noise reduction mechanism provided in this application;

[0040] Figure 16 A schematic diagram of the internal shaft and through-hole of the noise reduction mechanism provided in this application;

[0041] Figure 17 A schematic diagram of the internal shaft and sound-absorbing components of the noise reduction mechanism provided in this application;

[0042] Figure 18 A schematic diagram of the structure of the foam metal shaft of the noise reduction mechanism provided in this application.

[0043] Explanation of reference numerals in the attached figures:

[0044] 100. Phase inverter;

[0045] 200. Internal shaft; 210. Airflow gap; 220. Connecting part; 230. Variable diameter part;

[0046] 240. Protrusion; 250. Groove; 260. Spiral groove; 270. First groove; 280. Second groove;

[0047] 290. Cavity; 291. Through hole;

[0048] 300. Support;

[0049] 400. Support rod;

[0050] 500, External support; 510, Internal support; 520, Curved rod;

[0051] 600. Sound-absorbing components;

[0052] 700. Enclosure;

[0053] 800, cabinet; 810, speaker.

[0054] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0055] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application.

[0056] In related technologies, a speaker enclosure includes a cabinet, a loudspeaker, and a bass reflex port. The loudspeaker is connected to the cabinet, one end of the bass reflex port passes through the cabinet and communicates with the outside of the cabinet, and the other end of the bass reflex port extends into the inside of the cabinet. By rationally designing the dimensions of the cabinet and the bass reflex port, the sound waves radiated from the bass reflex port and the sound waves radiated from the front of the loudspeaker diaphragm are superimposed in phase at low frequencies, thereby enhancing the bass output.

[0057] The use of a bass reflex port makes it impossible to systematically optimize and adjust the airflow distribution and velocity within the entire section of the port. After entering the port, the airflow will re-converge and concentrate in the central area of ​​the port, forming a high-speed airflow jet. This high-speed airflow continuously rubs against the inner wall of the port, creating a large amount of irregular turbulence and eddies within the jet, which continuously generates significant airflow noise. This noise is superimposed on the low-frequency sound waves output by the port, interfering with the purity of the low-frequency sound waves and weakening the speaker's low-frequency performance, thus reducing the overall sound quality of the speaker to some extent.

[0058] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0059] Combination Figure 1 and Figure 2 This application provides a noise reduction mechanism, including a bass reflex tube 100 and an internal shaft 200. The bass reflex tube 100 is disposed inside the cabinet 800 of a speaker. One end of the bass reflex tube 100 is connected to the inner wall of the cabinet 800, and the other end of the bass reflex tube 100 is extended into the interior of the cabinet 800. The internal shaft 200 is disposed inside the bass reflex tube 100, and an airflow gap 210 is formed between the outer peripheral wall of the internal shaft 200 and the inner peripheral wall of the bass reflex tube 100.

[0060] In this embodiment, the phase inverter 100 has a circular cross-section, and both ends of the phase inverter 100 are flared. The cross-sectional area of ​​the flared opening gradually increases in the direction away from the center of the phase inverter 100. The cross-section of the inner shaft 200 is circular. In some embodiments, the cross-sectional shapes of the phase inverter 100 and the inner shaft 200 can be adaptively adjusted as needed, such as square, elliptical, racetrack-shaped, or other closed cross-sectional structures.

[0061] In this embodiment, the internal shaft 200 and the phase inverter tube 100 are coaxially arranged. In some embodiments, the internal shaft 200 and the phase inverter tube 100 may be eccentrically arranged.

[0062] By adopting the above technical solution, during speaker operation, the diaphragm of the speaker 810 repeatedly pushes and draws in the air inside the cabinet 800. The air pressure inside the cabinet 800 changes periodically, creating a pressure difference with the outside of the cabinet 800. The air relies on this pressure difference to travel back and forth through the bass reflex tube 100. After entering the bass reflex tube 100, the airflow is split into the annular airflow gap 210 formed by the inner peripheral wall of the bass reflex tube 100 and the outer peripheral wall of the internal shaft 200. The airflow flows in layers around the inner and outer walls of the airflow gap 210. The high-speed airflow originally concentrated in the center of the bass reflex tube 100 is split and dispersed by the internal shaft 200, resulting in a more uniform airflow path distribution. The internal shaft 200, coaxially located inside the bass reflex tube 100, works in conjunction with the annular airflow gap. The distance 210 can split the original concentrated airflow bundle and change the single flow channel structure, reducing the maximum and average flow velocity of the airflow inside the bass reflex tube 100. The reduced airflow velocity can reduce the intensity of turbulence during the airflow process, weaken the disturbance caused by the friction between the airflow and the tube wall, and thus reduce the airflow noise generated by the airflow disturbance. This optimizes the airflow state inside the bass reflex tube 100, weakens the probability of eddies caused by sudden airflow changes, and reduces the proportion of extra noise in the low-frequency band of the speaker after reducing airflow noise. The purity of low-frequency sound waves is improved, and the superposition effect of the low-frequency sound waves radiated from the front of the speaker 810 diaphragm and the low-frequency sound waves output by the bass reflex tube 100 is more stable, resulting in a certain degree of improvement in the overall sound quality of the speaker.

[0063] Combination Figure 3 and Figure 4In this embodiment, the phase inverter tube 100 is a straight tube and the internal shaft 200 is a straight shaft. In some embodiments, when the overall shape of the phase inverter tube 100 changes, the shape of the internal shaft 200 can be adaptively adjusted. For example, when the phase inverter tube 100 is set as an L-shaped tube, the internal shaft 200 is set as an L-shaped shaft accordingly. When the phase inverter tube 100 is set as an arc-shaped tube, the internal shaft 200 is set as an arc-shaped shaft accordingly.

[0064] Combination Figure 2 and Figure 5 One end of the internal shaft 200 is used to connect to the inner wall of the enclosure 800 or the speaker 810 of the speaker enclosure, and the other end of the internal shaft 200 extends toward the interior of the bass reflex tube 100.

[0065] In some embodiments, one end of the internal shaft 200 is used to connect to the inner wall of the housing 800, and the other end of the internal shaft 200 extends toward the interior of the phase inverter tube 100.

[0066] In this embodiment, the end of the internal shaft 200 located inside the phase inverter tube 100 is configured in a hemispherical shape.

[0067] By adopting the above technical solution, the arrangement of fixing one end of the internal shaft 200 to the inner wall of the cabinet 800 and extending the other end into the interior of the bass reflex tube 100 results in a simple overall assembly structure. The coaxial positioning of the internal shaft 200 can be completed without the need for additional brackets, clips, or other auxiliary fixing parts, simplifying the overall assembly process of the noise reduction mechanism. At the same time, the suspended internal shaft 200 can completely occupy the central area of ​​the bass reflex tube 100, stably separating the surrounding uniform airflow spacing 210. It will not disrupt the stratified flow state of the airflow inside the bass reflex tube 100 due to additional support components occupying the airflow space. It can continuously reduce the maximum and average flow velocity of the airflow inside the bass reflex tube 100, weaken the generation of turbulence and eddies inside the bass reflex tube 100, and play an auxiliary role in reducing airflow noise. It can also reduce the problems of airflow obstruction and local airflow abrupt changes caused by additional support structures, better maintain the smooth flow of airflow inside the bass reflex tube 100, and help improve the purity of the low-frequency sound of the speaker.

[0068] In some embodiments, one end of the inner shaft 200 is used to connect to the speaker 810 of the speaker enclosure, and the other end of the inner shaft 200 extends toward the interior of the bass reflex tube 100.

[0069] By adopting the above technical solution, the arrangement of fixing one end of the internal shaft 200 to the speaker 810 and extending the other end into the bass reflex tube 100 eliminates the need for additional fixing points in the enclosure 800. The assembly structure is simple, and the coaxial positioning of the internal shaft 200 can be achieved solely through the structure of the speaker 810 itself, reducing the need for additional fixing components. During the operation of the speaker 810, the diaphragm continuously vibrates, causing the air inside the enclosure 800 to form a reciprocating airflow. This airflow passes through the bass reflex tube 100, where the internal shaft 200 and the bass reflex tube 100 are connected. When the annular airflow spacing 210 formed by the wall is continuous, it will flow through the back area of ​​the speaker 810. The flowing airflow can carry away some of the heat generated by the back of the speaker 810 during operation, which helps to reduce the operating temperature rise of the speaker 810. At the same time, the suspended internal shaft 200 can divide the concentrated airflow bundle inside the bass reflex tube 100, reduce the maximum and average airflow velocity inside the bass reflex tube 100, weaken the generation of turbulence and eddies inside the bass reflex tube 100, reduce airflow noise, and avoid unnecessary noise interference with low frequency output, thereby improving the purity of the low frequency sound of the speaker.

[0070] In some embodiments, one end of the internal shaft 200 can be connected to the inner wall of the enclosure 800 or the speaker 810 by means of adhesive bonding, bolting, injection molding, snap-fit, or magnetic attachment. Adhesive bonding eliminates the need for assembly holes, simplifying assembly and preserving the original structural integrity of the enclosure 800 and speaker 810. After bonding, there are no exposed protrusions 240, reducing local airflow disturbance. Bolted connections offer convenient assembly and disassembly, providing a secure and stable connection. They also facilitate the individual removal and replacement of internal shaft 200 components, preventing loosening or shifting after long-term use and maintaining stable coaxiality of the internal shaft 200. Injection molding allows the internal shaft 200 to be integrated with the enclosure 800. 00. The speaker 810 base forms an integral structure with high connection strength and no connection gaps, which can reduce the additional airflow noise generated at the gaps; the snap-fit ​​limit does not require adhesives and fasteners, and the structure itself can achieve quick disassembly and assembly, which is more efficient and suitable for mass production; the magnetic bonding is flexible in disassembly and assembly, and will not cause damage such as drilling or glue residue to the surface of the cabinet 800 and speaker 810. The magnetic positioning can ensure the stable installation position of the internal shaft 200. Various connection methods can reliably fix the internal shaft 200 and keep it coaxial in the bass reflex tube 100, stably separating the airflow spacing 210 to reduce the airflow velocity in the bass reflex tube 100 and weaken the airflow noise.

[0071] Combination Figure 3 and Figure 4 In some embodiments, a support 300 is also included, which is used to connect with the outer wall of the housing 800. One end of the internal shaft 200 is used to connect with the inner wall of the housing 800, and the other end of the internal shaft 200 is connected with the support 300.

[0072] By adopting the above technical solution, a support 300 is installed on the outer wall of the enclosure 800, and one end of the internal shaft 200 is connected to the inner wall of the enclosure 800, while the other end is connected to the support 300 to achieve two-end fixation. This eliminates the single-end suspension installation method, significantly improving the overall structural rigidity of the internal shaft 200. It suppresses the shaking and displacement of the internal shaft 200 caused by airflow impact and vibration during speaker operation, continuously and stably maintaining the coaxial positional relationship between the internal shaft 200 and the bass reflex tube 100. This ensures a uniform and continuous annular airflow gap 210 between the inner wall of the bass reflex tube 100 and the outer wall of the internal shaft 200, preventing... The tilt of the internal shaft 200 causes the local airflow spacing 210 to vary in width, resulting in additional turbulent noise. The fixed structure constrained at both ends does not need to rely on a single-end support to bear the entire airflow impact force, thus improving structural durability. It is less likely to deform during long-term use, and the effects of airflow diversion, speed reduction, and noise reduction can be maintained stably. At the same time, the support 300 is arranged outside the enclosure 800 and does not occupy the internal acoustic space of the enclosure 800, nor does it obstruct the airflow inside the enclosure. It can continuously weaken the vortex formed by the high-speed airflow inside the bass reflex tube 100, slightly reduce airflow noise, and improve the purity of low-frequency sound.

[0073] In this embodiment, the support 300 is an L-shaped plate. One side of the L-shaped plate is connected to the outer wall of the housing 800, and the other side extends to the end of the inner shaft 200 away from the inner wall of the housing 800 and is disposed opposite to the end of the inner shaft 200. In some embodiments, the shape of the support 300 can be adapted as needed. For example, the support 300 can be set as a U-shaped plate with the notch of the U-shaped plate facing the end of the inner shaft 200, or the support 300 can be set as an arc-shaped plate with the notch of the arc-shaped plate facing the end of the inner shaft 200.

[0074] like Figure 6 As shown, in some embodiments, the noise reduction mechanism further includes at least one support rod 400, one end of which is connected to the outer wall of the inner shaft 200, and the other end of which is connected to the inner wall of the phase inverter tube 100.

[0075] By adopting the above technical solution, at least one support rod 400 is added between the outer wall of the inner shaft 200 and the inner wall of the bass reflex tube 100 to connect the inner shaft 200 and the bass reflex tube 100. This provides multi-directional support and constraint for the inner shaft 200, effectively reducing the vibration and displacement of the inner shaft 200 caused by the reciprocating airflow impact within the bass reflex tube 100 during speaker operation. It also stably maintains the coaxial arrangement of the inner shaft 200 and the bass reflex tube 100, ensuring that the annular airflow gap 210 between the inner shaft 200 and the bass reflex tube 100 is uniform in width at all points, and reducing the risk of misalignment of the inner shaft 200. The high-speed turbulence caused by the narrowing of the local channel is dispersed and absorbed by the support rod 400, which improves the overall structural stability and service life of the internal shaft 200. Even under long-term vibration conditions, it is not easy to shift its position. It can continuously and stably split the concentrated airflow bundle inside the bass reflex tube 100 and reduce the overall airflow velocity to weaken eddies and airflow noise. The small number of support rods 400 occupy a limited airflow space and will only slightly change the local airflow direction. The negative impact on the overall airflow smoothness is small, which can continuously ensure the noise reduction effect and improve the purity of the low-frequency output sound of the speaker.

[0076] In some embodiments, the shape and number of support rods 400 can be adaptively adjusted as needed. For example, the support rods 400 can be cylindrical rods, flat ribs, arc-shaped guide ribs, etc., and the number can be set to two, three or four and evenly distributed along the circumference of the inner axis 200. The evenly distributed support rods 400 can evenly support the inner axis 200 and reduce the situation of unilateral force tilting. Flat and arc-shaped support rods 400 can also play a small guiding role for the passing airflow and moderately weaken the local vortex generated at the position of the support rods 400.

[0077] Combination Figure 7 and Figure 8 In some embodiments, the noise reduction mechanism further includes an outer bracket 500 and an inner bracket 510. The outer bracket 500 is used to connect to the outer wall of the housing 800, and the inner bracket 510 is used to connect to the outer wall of the phase inverter tube 100. One end of the inner shaft 200 is connected to the outer bracket 500, and the other end of the inner shaft 200 is connected to the inner bracket 510.

[0078] By adopting the above technical solution, and by separately setting an outer support 500 connecting to the outer wall of the housing 800 and an inner support 510 connecting to the outer wall of the phase inverter tube 100, and by correspondingly assembling both ends of the internal shaft 200 onto the outer support 500 and the inner support 510 to achieve double-end positioning and fixation, it is possible to avoid the outer support 500 and the inner support 510 being inside the phase inverter tube 100, thus preventing damage to the original airflow space within the phase inverter tube 100 and the generation of additional airflow noise. The inner support 510 and the outer support 500 are located within the phase inverter tube 100. The external constraint on the internal shaft 200 significantly improves the overall structural rigidity of the internal shaft 200, reduces the shaking and displacement of the internal shaft 200 caused by the impact of reciprocating airflow in the bass reflex tube 100 and the vibration of the whole machine during speaker operation, and stably maintains the coaxial relationship between the internal shaft 200 and the bass reflex tube 100. This ensures that the width of the annular airflow distance 210 between the internal shaft 200 and the bass reflex tube 100 is uniform at all points, and reduces turbulent noise caused by the narrowing of local channels due to the tilt of the internal shaft 200.

[0079] In this embodiment, both the outer support 500 and the inner support 510 include a plurality of arc-shaped rods 520. The plurality of arc-shaped rods 520 of the outer support 500 are evenly distributed along the circumference of the inner shaft 200. One end of the plurality of arc-shaped rods 520 of the outer support 500 is connected to the outer wall of the housing 800, and the other end of the plurality of arc-shaped rods 520 of the outer support 500 is connected to the outer wall of the inner shaft 200. The notches of the plurality of arc-shaped rods 520 of the outer support 500 are set towards the inner shaft 200. The plurality of arc-shaped rods 520 of the inner support 510 are evenly distributed along the circumference of the inner shaft 200. One end of the plurality of arc-shaped rods 520 of the inner support 510 is connected to the outer wall of the phase inverter tube 100, and the other end of the plurality of arc-shaped rods 520 of the inner support 510 is connected to the outer wall of the inner shaft 200.

[0080] By adopting the above technical solution, both the outer support 500 and the inner support 510 use arc-shaped rods 520 evenly arranged circumferentially along the inner shaft 200. The concave openings of the arc-shaped rods 520 face the inner shaft 200, forming a ring-shaped support structure. This distributes the airflow impact and overall vibration load on the inner shaft 200 evenly at multiple points, thus distributing the force evenly and reducing the load on a single arc-shaped rod 520. This also reduces the possibility of deformation and loosening of the arc-shaped rods 520. Compared to straight rods, the smooth curved surface of the arc-shaped rods 520 can weaken the airflow interruption phenomenon when the airflow passes through the inner support 510 and the outer support 500. The design significantly reduces turbulent noise generated outside the inner support 510 and outer support 500. At the same time, the encircling layout of the arc-shaped rod 520 can stably lock the coaxial position of the inner shaft 200, preventing radial displacement of the inner shaft 200. It continuously maintains a uniform annular airflow spacing 210 between the inner wall of the phase inverter tube 100 and the outer wall of the inner shaft 200, ensuring the stable performance of the airflow diversion and deceleration effect inside the phase inverter tube 100. The arc-shaped rod 520 occupies less assembly space and will not excessively encroach on the arrangement space outside the housing 800 and the phase inverter tube 100. The overall structure is compact and the assembly force balance is improved.

[0081] like Figure 8 As shown, in some embodiments, the two ends of the phase inverter 100 are set as flared mouths, and the internal shaft 200 includes a connecting part 220 and a variable diameter part 230. Both ends of the connecting part 220 are provided with variable diameter parts 230, and the cross-sectional area of ​​the variable diameter part 230 gradually decreases along the direction away from the connecting part 220.

[0082] In this embodiment, the variable diameter portions 230 at both ends of the connecting portion 220 are respectively provided with corresponding flared openings at both ends of the phase inverter tube 100.

[0083] By adopting the above technical solution, using a connecting part 220 and variable diameter parts 230 located at both ends of the connecting part 220 with a cross-sectional area gradually decreasing away from the connecting part 220, and with the variable diameter parts 230 at both ends corresponding to the flared openings at both ends of the phase inverter tube 100, the outer contour of the variable diameter part 230 can form a matching gradually expanding annular airflow spacing 210 with the gradually expanding inner wall of the flared opening. When the airflow enters and exits the port of the phase inverter tube 100, there will be no sudden change in the channel cross-section, which can smoothly guide the airflow to complete the splitting and merging, reducing the output pressure of the phase inverter tube 100. The airflow impact intensity at the inlet position weakens the generation of vortices at the port. At the same time, the gradual transition from coarse to fine structure of the variable diameter section 230 allows the width of the annular airflow spacing 210 to smoothly transition synchronously with the horn mouth, maintaining a state of uniform airflow stratification throughout the process. This further reduces the maximum and average airflow velocity within the bass reflex tube 100, helps reduce noise caused by airflow friction, and can also work with the horn mouth to form a complete and continuous guide profile, improving airflow smoothness, reducing noise superimposed on low-frequency sound waves, and slightly improving the purity of the speaker's low-frequency output.

[0084] Combination Figures 9 to 14 Multiple protrusions 240 are provided on the outer wall of the inner shaft 200;

[0085] Alternatively, multiple grooves 250 may be provided on the outer wall of the inner shaft 200;

[0086] Alternatively, a spiral groove 260 may be provided on the outer wall of the inner shaft 200;

[0087] Alternatively, there is at least one first groove 270 on the outer wall of the inner shaft 200, and the first groove 270 is arranged along the axial direction of the inner shaft 200;

[0088] Alternatively, a plurality of second grooves 280 are provided on the outer wall of the inner shaft 200, and each second groove 280 is arranged circumferentially along the outer wall of the inner shaft 200.

[0089] In some embodiments, a plurality of protrusions 240 are provided on the outer wall of the inner shaft 200.

[0090] In this embodiment, multiple protrusions 240 are evenly distributed on the outer wall of the inner shaft 200, and each protrusion 240 is hemispherical.

[0091] By adopting the above technical solution, multiple protrusions 240 are set on the outer wall of the inner shaft 200. When the airflow passes through the annular airflow spacing 210 inside the bass reflex tube 100, it will generate a small disturbance with the surface of the protrusions 240. This can break up a large area of ​​continuous high-speed airflow layer, decompose a single concentrated airflow into multiple fine airflows, moderately weaken the relative velocity difference between airflow layers, and reduce the turbulence intensity generated by large-area friction of airflow. At the same time, the protrusions 240 can slightly extend the contact path between the airflow and the outer wall of the inner shaft 200, gently reduce the overall airflow velocity, and weaken the probability of generating large-scale vortices inside the bass reflex tube 100. This reduces the airflow noise caused by airflow disturbance. Moreover, the size of the protrusions 240 is controllable and will not significantly compress the annular airflow spacing 210 to cause a surge in local velocity. It can work in conjunction with the diversion effect of the inner shaft 200 to further optimize the airflow state inside the bass reflex tube 100, reduce the interference of excess noise on low-frequency sound, and improve the purity of the low-frequency sound of the speaker to a certain extent.

[0092] In some embodiments, a plurality of grooves 250 are provided on the outer wall of the inner shaft 200.

[0093] In this embodiment, multiple grooves 250 are evenly distributed on the outer wall of the inner shaft 200, and each groove 250 is hemispherical.

[0094] By adopting the above technical solution, multiple grooves 250 are opened on the outer wall of the inner shaft 200. When the airflow flows through the annular airflow gap 210 between the bass reflex tube 100 and the inner shaft 200, some airflow will flow into the groove 250 to form a low-speed buffer air layer. The buffer air layer can block the high-speed airflow from directly rubbing against the outer wall of the inner shaft 200 over a large area, reducing the airflow noise generated by the friction between the airflow and the wall of the inner shaft 200. At the same time, the groove 250 can divide the continuous and complete airflow layer, disperse the large-scale high-speed airflow that is easy to form large-scale vortices, reduce the formation range and intensity of vortices in the bass reflex tube 100, smooth the amplitude of sudden changes in airflow velocity, and help reduce the airflow noise generated by airflow disturbance. The groove 250 will not excessively compress the airflow cross section and cause a sudden increase in local flow velocity. It can work with the internal shaft 200 splitting structure to continuously optimize the airflow state in the bass reflex tube 100, reduce noise mixing into low-frequency sound waves, and slightly improve the purity of the speaker's low-frequency sound.

[0095] In some embodiments, a spiral groove 260 is provided on the outer wall of the inner shaft 200.

[0096] In this embodiment, the cross-section of the spiral groove 260 can be set as U-shaped, V-shaped or arc-shaped.

[0097] By adopting the above technical solution, a spiral groove 260 is opened on the outer wall of the inner shaft 200. When the airflow flows back and forth within the annular airflow gap 210 between the bass reflex tube 100 and the inner shaft 200, the spiral groove 260 can guide the airflow to travel in an orderly manner along the spiral trajectory, disperse the originally parallel and concentrated high-speed airflow, reduce the velocity difference between airflow layers, and weaken the turbulence generated by friction of large-area parallel airflow. The interior of the spiral groove 260 can form a low-speed buffer airflow area, which can alleviate the vibration disturbance caused by the airflow directly impacting the outer wall of the inner shaft 200. At the same time, the spiral groove 260 extends the airflow path, gradually reduces the overall airflow velocity, and reduces the probability of generating large-scale vortices in the bass reflex tube 100, thereby reducing the airflow noise generated by airflow disturbance. The spiral groove 260 will not significantly encroach on the airflow gap 210 to cause a sudden increase in local velocity, optimize the airflow state in the bass reflex tube 100, reduce the superposition of extra noise in low-frequency sound waves, and improve the purity of the low-frequency output sound of the speaker to a certain extent.

[0098] In some embodiments, the outer wall of the inner shaft 200 has at least one first groove 270, which is arranged along the axial direction of the inner shaft 200.

[0099] In this embodiment, the cross-section of the first groove 270 can be set as U-shaped, V-shaped or arc-shaped.

[0100] By adopting the above technical solution, at least one first groove 270 is arranged along the inner shaft 200. When the airflow flows within the annular airflow gap 210 formed between the inner wall of the bass reflex tube 100 and the outer wall of the inner shaft 200, part of the airflow can flow into the axially extended first groove 270 to form a low-speed buffer airflow zone. This weakens the frictional disturbance caused by the high-speed airflow directly contacting the outer wall of the inner shaft 200. The axial first groove 270 can longitudinally divide the continuous airflow, disperse the concentrated airflow bundle that is easy to gather and form strong turbulence, reduce the coverage and disturbance intensity of the airflow turbulence, smooth the sudden change in airflow velocity, reduce the probability of vortex generation in the bass reflex tube 100, and thus reduce the airflow noise caused by airflow disturbance. The first groove 270 will not significantly reduce the overall airflow cross-sectional area and cause a sharp increase in local flow velocity. It can improve the uniformity of airflow in the bass reflex tube 100, reduce the mixing of noise into low-frequency sound waves, and slightly improve the purity of the speaker's low-frequency sound.

[0101] In some embodiments, a plurality of second grooves 280 are provided on the outer wall of the inner shaft 200, and each second groove 280 is arranged circumferentially along the outer wall of the inner shaft 200.

[0102] In this embodiment, the cross-section of the second groove 280 can be set as U-shaped, V-shaped or arc-shaped.

[0103] By adopting the above technical solution, multiple circumferentially extending second grooves 280 are arranged on the outer wall of the inner shaft 200. When the airflow passes through the annular airflow gap 210 between the phase inverter 100 and the inner shaft 200, the circumferential second grooves 280 can intercept part of the airflow in segments along the circumference and form a low-speed buffer air layer within the second grooves 280, weakening the frictional vibration caused by the continuous adhesion of high-speed airflow to the outer wall of the inner shaft 200. At the same time, the multiple circumferential second grooves 280 can break up continuous long strips of airflow along the axial direction, breaking up the easily continuous... The developed elongated turbulent structure weakens the shear disturbance between airflow layers with different flow velocities, reduces the scale of vortex formation within the bass reflex tube 100, and smooths out sudden changes in local airflow velocity. This reduces airflow noise caused by airflow friction and turbulence. The second channel 280 only slightly alters the local flow cross-section and will not cause a surge in flow velocity due to narrowing of the overall channel. It can work with the flow diversion effect of the internal shaft 200 to optimize the airflow state within the bass reflex tube 100, reduce noise interference to low-frequency output, and improve the purity of the speaker's low-frequency sound to a certain extent.

[0104] Combination Figures 15 to 17 In some embodiments, a sound-absorbing element 600 is also included. The inner shaft 200 has a cavity 290 inside and a plurality of through holes 291 on the inner shaft 200. The through holes 291 connect the cavity 290 and the airflow gap 210. The sound-absorbing element 600 fills the inside of the cavity 290.

[0105] By adopting the above technical solution, a cavity 290 is opened inside the inner shaft 200 and filled with a sound-absorbing component 600. Simultaneously, multiple through holes 291 are provided on the wall of the inner shaft 200, connecting the cavity 290 to the outer annular airflow gap 210. Airflow noise generated by the airflow within the phase inverter 100 can be transmitted into the cavity 290 through the through holes 291. The sound-absorbing component 600 filling the cavity 290 can absorb and dissipate the transmitted noise waves, weakening the intensity of the noise waves reflected back to the airflow gap 210. At the same time, the through holes 291 can absorb and dissipate the noise waves. The passing airflow forms a small throttling buffer effect, smoothing local airflow velocity fluctuations and reducing secondary noise generated by airflow shearing. The cavity 290 does not occupy the airflow passage on the outside of the internal shaft 200, and will not cause the annular airflow distance 210 to narrow and cause a sudden increase in flow velocity. It can work together with the internal shaft 200 flow diversion and speed reduction structure to simultaneously suppress airflow noise in the bass reflex tube 100 from two dimensions: sound source absorption and smooth airflow guidance. This reduces the superposition of excess noise into the low-frequency output sound wave and further improves the purity of the speaker's low-frequency sound.

[0106] In this embodiment, the sound-absorbing component 600 can be foam sound-absorbing material, fibrous sound-absorbing material, granular sound-absorbing material, or metal sound-absorbing material. When foam sound-absorbing material is selected to fill the cavity 290, the material is densely covered with tiny interconnected pores 291, which is convenient to process and mold, and can efficiently absorb mid-to-high frequency airflow noise, making it suitable for mass production. Fiber sound-absorbing material has a multi-layered interwoven fiber structure, a wider sound absorption frequency range, and good dissipation capability for airflow disturbance noise in different frequency bands, thus improving the buffering effect of airflow vibration. Granular sound-absorbing material consumes sound wave energy by relying on the irregular gaps between particles, has stronger structural stability, and is not prone to deformation and collapse under long-term airflow vibration, thus maintaining a stable sound absorption effect. Metal sound-absorbing material has excellent high temperature resistance and vibration resistance, is not easily affected by moisture and deterioration, and is suitable for high-power speaker long-term high-load working scenarios. All four types of sound-absorbing components 600 can receive airflow noise inside the bass reflex tube 100 and dissipate sound wave energy through the through holes 291, and work together with the internal shaft 200 structure to reduce airflow noise and improve the purity of the speaker's low-frequency output.

[0107] In some embodiments, the noise reduction mechanism further includes a closure 700, which extends through the inner shaft 200 at least one end of the cavity 290 along the axial direction of the inner shaft 200. The closure 700 is used to insert into or disengage from the end of the cavity 290 to close or open the cavity 290.

[0108] In this embodiment, one end of the cavity 290 is disposed through the inner shaft 200 along the axial direction of the inner shaft 200, and the sealing member 700 includes a plug for inserting into or disengaging from the end of the cavity 290 to close or open the cavity 290.

[0109] By adopting the above technical solution, the cavity 290 of the internal shaft 200 is open at least one end along the axial direction of the internal shaft 200. With the sealing component 700, the end of the cavity 290 can be closed and opened. During routine maintenance, only the sealing component 700 needs to be removed to directly take out the sound-absorbing component 600 inside the cavity 290 for replacement, cleaning, or replacement with a sound-absorbing component 600 with different sound absorption performance. There is no need to completely disassemble the internal shaft 200, the bass reflex tube 100, or even the speaker cabinet 800. This greatly simplifies the disassembly and assembly of the sound-absorbing component 600 and reduces the difficulty of maintenance. The plug-in assembly of the sealing component 700 has good sealing performance. After assembly, it can prevent airflow from overflowing from the end of the cavity 290, preventing additional airflow turbulence and noise generation. After replacing the sound-absorbing component 600 with one suitable for the working conditions, the cavity 290 can continuously maintain its ability to absorb and dissipate airflow noise, stabilize and weaken the airflow noise inside the bass reflex tube 100, and ensure the purity of the low-frequency sound of the speaker.

[0110] like Figure 18 As shown, at least part of the internal shaft 200 is set as a foam metal shaft.

[0111] In this embodiment, the entire internal shaft 200 is a foam metal shaft.

[0112] By adopting the above technical solution, the interior of the foam metal shaft is filled with interconnected micropores. When the airflow flows through the annular airflow gap 210 between the phase reversing tube 100 and the foam metal shaft, the noise waves generated by airflow friction and turbulence can directly penetrate into the internal pores of the foam metal shaft and be dissipated and absorbed. There is no need to open additional cavities 290, through holes 291, or fill with independent sound-absorbing components 600, which simplifies the overall structure and assembly process of the noise reduction mechanism. The foam metal shaft has the structural strength of a metal matrix, which can stably maintain the coaxial shape of the internal shaft 200 and resist the impact of reciprocating airflow without deformation or displacement. At the same time, the foam metal shaft has excellent air permeability and buffering characteristics, which can smooth the sudden change in local airflow velocity and weaken the degree of eddy generation. It has the dual functions of diversion and guidance and sound absorption and noise reduction. The foam metal shaft is resistant to high temperature, vibration, and moisture and aging, and is suitable for long-term high-power sound output conditions of the speaker. It continuously reduces the airflow noise in the phase reversing tube 100 and improves the purity of low-frequency output sound.

[0113] This application embodiment also provides a speaker, including a cabinet 800 and a noise reduction mechanism of any of the above embodiments. The bass reflex tube 100 of the noise reduction mechanism is disposed inside the cabinet 800. One end of the bass reflex tube 100 is connected to the inner wall of the cabinet 800, and the other end of the bass reflex tube 100 extends into the interior of the cabinet 800.

[0114] The specific structure of the noise reduction mechanism has been described in detail in the above embodiments, and will not be repeated here.

[0115] The speaker provided in this application, by setting a noise reduction mechanism, allows airflow within the enclosure 800 to continuously enter and exit the bass reflex tube 100 during operation, following the reciprocating motion of the speaker 810 diaphragm. Traditional bass reflex tubes 100 with only horn openings at both ends can only provide simple airflow guidance, easily forming concentrated high-speed airflow jets and generating turbulent eddies, resulting in airflow noise polluting low-frequency sound quality. This application provides an internal shaft 200 within the bass reflex tube 100. The internal shaft 200 is stably maintained coaxially with the bass reflex tube 100 through various methods, including single-end connection to the inner wall of the enclosure 800 or the speaker 810, two-end cooperation with the inner support 510 and outer support 500, and the addition of a support rod 400 within the bass reflex tube 100. This is achieved through the internal shaft 200 body and the variable diameter section 2. The 30 and the horn of the bass reflex tube 100 are matched to form an annular airflow spacing 210, which disperses the concentrated airflow bundle and smooths the sudden change in airflow velocity to weaken eddies. Protrusions 240, first grooves 270, second grooves 280 or spiral grooves 260 can be added to the outer wall of the inner shaft 200 to further divide the airflow and form a buffer air layer to reduce friction noise. A cavity 290 can be opened inside the inner shaft 200 to match, and the cavity 290 is filled with sound-absorbing components 600 to absorb dissipated airflow noise. The inner shaft 200 optimizes the airflow state inside the bass reflex tube 100 from multiple levels of flow diversion, airflow buffering and noise absorption, which greatly reduces the airflow noise caused by turbulence and friction inside the bass reflex tube 100, prevents noise from superimposing on low-frequency sound waves, and effectively improves the purity of the speaker's low-frequency output.

[0116] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope.

Claims

1. A noise reduction mechanism, characterized in that, include: A bass reflex tube (100) is used to be installed inside the cabinet (800) of the speaker. One end of the bass reflex tube (100) is used to connect to the inner wall of the cabinet (800), and the other end of the bass reflex tube (100) is used to extend into the interior of the cabinet (800). An internal shaft (200) is disposed inside the phase inverter tube (100), and an airflow gap (210) is formed between the outer peripheral wall of the internal shaft (200) and the inner peripheral wall of the phase inverter tube (100).

2. The noise reduction mechanism according to claim 1, characterized in that, One end of the internal shaft (200) is used to connect to the inner wall of the enclosure (800) or the speaker (810) of the speaker enclosure, and the other end of the internal shaft (200) extends toward the interior of the bass reflex tube (100).

3. The noise reduction mechanism according to claim 1, characterized in that, It also includes a support (300) for connecting to the outer wall of the housing (800), one end of the internal shaft (200) for connecting to the inner wall of the housing (800), and the other end of the internal shaft (200) for connecting to the support (300).

4. The noise reduction mechanism according to claim 1, characterized in that, It also includes at least one support rod (400), one end of which is connected to the outer wall of the inner shaft (200), and the other end of which is connected to the inner wall of the phase inverter (100).

5. The noise reduction mechanism according to claim 1, characterized in that, It also includes an outer bracket (500) and an inner bracket (510), the outer bracket (500) being used to connect to the outer wall of the housing (800), the inner bracket (510) being used to connect to the outer wall of the phase inverter (100), one end of the inner shaft (200) being connected to the outer bracket (500), and the other end of the inner shaft (200) being connected to the inner bracket (510).

6. The noise reduction mechanism according to any one of claims 1-5, characterized in that, The two ends of the phase inverter tube (100) are set as flared mouths. The internal shaft (200) includes a connecting part (220) and a variable diameter part (230). The variable diameter part (230) is provided at both ends of the connecting part (220). The cross-sectional area of ​​the variable diameter part (230) gradually decreases along the direction away from the connecting part (220).

7. The noise reduction mechanism according to any one of claims 1-5, characterized in that, The outer wall of the inner shaft (200) is provided with a plurality of protrusions (240); Alternatively, the outer wall of the inner shaft (200) may be provided with a plurality of grooves (250); Alternatively, a spiral groove (260) may be provided on the outer wall of the inner shaft (200); Alternatively, the outer wall of the inner shaft (200) has at least one first groove (270), the first groove (270) being arranged along the axial direction of the inner shaft (200); Alternatively, a plurality of second grooves (280) are provided on the outer wall of the inner shaft (200), and each second groove (280) is arranged circumferentially along the outer wall of the inner shaft (200).

8. The noise reduction mechanism according to any one of claims 1-5, characterized in that, It also includes a sound-absorbing component (600), the inner shaft (200) has a cavity (290) inside, the inner shaft (200) has a plurality of through holes (291) on it, the through holes (291) connect the cavity (290) and the airflow gap (210), and the sound-absorbing component (600) fills the interior of the cavity (290).

9. The noise reduction mechanism according to claim 8, characterized in that, It also includes a closure (700) along the axial direction of the inner shaft (200), at least one end of the cavity (290) is disposed through the inner shaft (200), the closure (700) is used to insert into or disengage from the end of the cavity (290) to close or open the cavity (290).

10. The noise reduction mechanism according to any one of claims 1-5, characterized in that, At least part of the internal shaft (200) is configured as a foam metal shaft.

11. A speaker, characterized in that, The device includes a housing (800) and a noise reduction mechanism as described in any one of claims 1-10. The phase inversion tube (100) of the noise reduction mechanism is disposed inside the housing (800). One end of the phase inversion tube (100) is connected to the inner wall of the housing (800), and the other end of the phase inversion tube (100) extends into the housing (800).

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