Miniature horn with radiation ring magnetic circuit

Abstract

The application discloses a micro loudspeaker with a radiation ring magnetic circuit, which comprises an outer shell, a magnetic circuit, a voice coil, and a diaphragm. The diaphragm comprises a spherical top, a connecting part, a folded ring, and an outer ring part which are sequentially connected from inside to outside. The outer shell is provided with a positioning column, the positioning column has a hollow channel, the bottom of the outer shell is provided with a hollow sound hole corresponding to the hollow channel, and a plurality of circumferential sound holes are arranged on the bottom of the outer shell along the outer periphery of the hollow sound hole. The circumferential sound holes are communicated with the annular gap and form a sound adjusting channel opposite to the annular gap. The voice coil is arranged in the annular gap and comprises a hollow tube and a coil width outside the hollow tube. The coil width is arranged in the annular gap, the height of the coil width is less than or equal to the thickness of the middle magnet of the inner ring magnetic circuit and the outer ring magnetic circuit. The hollow channel is opposite to the diaphragm and forms another sound adjusting channel together with the diaphragm and the hollow channel. The design of the hollow sound hole can effectively increase the size of the magnetic circuit and the voice coil, improve the BL value of the loudspeaker, improve the frequency response characteristics, and thus improve the sensitivity of the loudspeaker.

Description

Technical Field

[0001] This invention relates to the field of loudspeaker technology, and in particular to a miniature loudspeaker with a radiating magnetic circuit. Background Technology

[0002] As we all know, a loudspeaker is a sound-producing device that converts electrical signals into audio signals. As electronic devices become thinner and smaller, the loudspeakers used in electronic devices naturally require miniaturization.

[0003] like Figure 7 As shown, this illustrates the conventional magnetic circuit speaker structure in traditional technology. This common miniature speaker typically includes a metal shell 50 and a magnet 60, a washer 70, a voice coil 30, and a diaphragm 80 housed within the shell 50. The washer 70 is mounted above the magnet 60. The upper end of the voice coil 30 is connected to the diaphragm 80, and a portion of the lower part of the voice coil 30 extends into the space between the washer 70 and the metal shell 50. A tuning hole 51 is located at the bottom of the metal shell 50, between the magnet 60 and the magnetic guide frame. Magnetic field lines generated by the magnet 60 pass through the washer 70 into the aforementioned space, then re-enter the magnetic guide frame and return to the magnet 60 to form a magnetic circuit. This magnetic circuit structure is relatively simple and prone to eddy current distortion. Furthermore, the location of the tuning hole affects the overall internal structure, limiting the size of the magnet 60 and voice coil 30, thus hindering the improvement of speaker sensitivity. Additionally, the circuit board of this miniature speaker is glued to the metal shell, which is time-consuming, labor-intensive, and prone to detachment, clearly failing to meet market demands.

[0004] Therefore, a new technical solution needs to be researched to address the above problems. Summary of the Invention

[0005] In view of this, the present invention addresses the deficiencies of the existing technology, and its main objective is to provide a miniature speaker with a radiating ring magnetic circuit, which can effectively increase the size of the magnetic circuit and voice coil, improve the speaker's BL value, improve frequency response characteristics, thereby enhancing the speaker's sensitivity and producing a good sound effect.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A miniature loudspeaker with a radiating magnetic circuit includes a housing, a magnetic circuit, a voice coil, and a diaphragm. The housing includes a bottom and an outer ring wall, which together form a cavity. The diaphragm, voice coil, and magnetic circuit are installed in the cavity of the housing. The diaphragm includes a dome, a connecting portion, a folded ring, and an outer ring portion connected sequentially from the inside to the outside. The voice coil is connected to the connecting portion, and the diaphragm is fixed to the housing through the outer ring portion. The ratio of the inner diameter of the dome to the inner diameter of the diaphragm is between 50% and 60%, and the height of the folded ring is between 0.4 mm and 0.5 mm.

[0008] The bottom of the outer shell is provided with a positioning column in the accommodating cavity, the positioning column has a hollow passage through the bottom of the outer shell, the bottom of the outer shell is provided with a hollow sound hole corresponding to the hollow passage, the hollow sound hole is communicated with the hollow passage, and a plurality of circumferential sound holes are arranged through the bottom of the outer shell along the outer periphery of the hollow sound hole.

[0009] The magnetic circuit comprises an inner ring magnetic circuit and an outer ring magnetic circuit, the inner ring magnetic circuit has an inner ring hole, and the outer ring magnetic circuit has an outer ring hole; the inner ring magnetic circuit is sleeved on the positioning column through the inner ring hole, the outer ring magnetic circuit is sleeved outside the inner ring magnetic circuit through the outer ring hole, and the outer wall of the inner ring magnetic circuit and the inner wall of the outer ring magnetic circuit form an annular gap; the inner ring magnetic circuit is composed of an upper inner magnetic ring, a middle inner magnetic ring and a lower inner magnetic ring in sequence, the outer ring magnetic circuit is composed of an upper outer magnetic ring, a middle outer magnetic ring and a lower outer magnetic ring in sequence, the upper inner magnetic ring, the lower inner magnetic ring, the upper outer magnetic ring and the lower outer magnetic ring are axial magnetic rings, the middle inner magnetic ring and the middle outer magnetic ring are radial magnetic rings, the magnetic lines of the upper outer magnetic ring, the upper inner magnetic ring, the middle inner magnetic ring and the middle outer magnetic ring form a closed magnetic loop, and the magnetic lines of the lower outer magnetic ring, the lower inner magnetic ring, the middle inner magnetic ring and the middle outer magnetic ring form a closed magnetic loop; the circumferential sound hole is communicated with the annular gap and faces the annular gap to form a sound adjusting passage.

[0010] The voice coil is arranged in the annular gap, the voice coil comprises a hollow tube and a coil located outside the hollow tube, the coil is located in the annular gap, the diaphragm is arranged above the voice coil and is combined with the top of the hollow tube, and the hollow passage faces the diaphragm and forms another sound adjusting passage together with the diaphragm.

[0011] As a preferred solution, the coil is located in the annular gap between the middle inner magnetic ring and the middle outer magnetic ring, and the height of the coil is less than or equal to the thickness of the middle inner magnetic ring and the middle outer magnetic ring.

[0012] As a preferred solution, the upper outer magnetic ring and the lower outer magnetic ring have the same magnetic pole at one end close to the middle outer magnetic ring, the upper inner magnetic ring and the lower inner magnetic ring have the same magnetic pole at one end close to the middle inner magnetic ring, the upper outer magnetic ring and the upper inner magnetic ring have opposite magnetic poles at one end close to the diaphragm, the middle outer magnetic ring and the middle inner magnetic ring have opposite magnetic poles at one end close to the voice coil, and the upper outer magnetic ring has opposite magnetic pole at one end close to the diaphragm to the magnetic pole at one end of the middle outer magnetic ring close to the voice coil.

[0013] As a preferred solution, the upper inner magnetic ring, the middle inner magnetic ring, the lower inner magnetic ring, the upper outer magnetic ring, the middle outer magnetic ring and the lower outer magnetic ring all have an integrated closed annular structure.

[0014] As a preferred solution, the residual magnetism of the upper inner magnetic ring, the residual magnetism of the lower inner magnetic ring are respectively less than the residual magnetism of the middle inner magnetic ring, and the residual magnetism of the upper inner magnetic ring and the lower inner magnetic ring superimposed is greater than the residual magnetism of the middle inner magnetic ring; the residual magnetism of the upper outer magnetic ring, the residual magnetism of the lower outer magnetic ring are respectively less than the residual magnetism of the middle outer magnetic ring, and the residual magnetism of the upper outer magnetic ring and the lower outer magnetic ring superimposed is greater than the residual magnetism of the middle outer magnetic ring.

[0015] As a preferred solution, the shell body has a solder pad which is integrally injection molded with the shell body.

[0016] As a preferred solution, the annular gap is 0.4mm-1.0mm.

[0017] As a preferred solution, the inner diameter size of the inner magnetic circuit is 2.5mm-3.5mm.

[0018] As a preferred solution, the shell body is respectively provided with a first tuning net and a second tuning net at positions corresponding to the hollow tuning hole and the circumferential tuning hole.

[0019] As a preferred solution, the wall thickness ratio of the inner magnetic circuit and the outer magnetic circuit is between 2 / 3 and 1.

[0020] The present application has obvious advantages and beneficial effects compared with the prior art. Specifically, as known from the above technical solution, the inner magnetic circuit and the outer magnetic circuit are constructed into a radiation ring magnetic circuit, the coil lap of the voice coil extends into the annular gap of the inner magnetic circuit and the outer magnetic circuit, the circumferential tuning hole is communicated with the annular gap and directly opposite to the annular gap to form a tuning channel, the hollow channel is directly opposite to the diaphragm and forms another tuning channel together with the diaphragm, the tuning channels are respectively designed in the positioning column sleeved by the inner hole of the inner magnetic circuit and at the position corresponding to the annular gap between the inner magnetic circuit and the outer magnetic circuit, thus, in the loudspeaker with the same outer diameter size, the magnetic circuit and the voice coil size can be effectively increased, the BL value of the loudspeaker is improved, the frequency response characteristic is improved, the sensitivity of the loudspeaker is improved, and good sound effect is produced.

[0021] Moreover, the diaphragm is fixed to the shell body through the outer ring part, the ratio of the inner diameter of the ball top to the inner diameter of the diaphragm is between 50% and 60%, and the height of the folded ring is between 0.4mm and 0.5mm, thus, the loudspeaker resonance frequency reaches 180-250Hz, the high frequency reaches 30KHz, the high frequency and the low frequency are considered at the same time, and good sound effect is produced at 20Hz-20KHz.

[0022] To make the structure characteristics and effects of the present application clearer, the present application will be described in detail below with reference to the drawings and specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a perspective view of an embodiment of the present application;

[0024] Figure 2 is a first cross-sectional view of an embodiment of the present application;

[0025] Figure 3 is an exploded view of an embodiment of the present application;

[0026] Figure 4 is a second cross-sectional view (axial magnetic lines) of an embodiment of the present application;

[0027] Figure 5 is a BL simulation curve comparison diagram of a micro loudspeaker with a radiation ring magnetic circuit and a conventional magnetic circuit loudspeaker of the present application;

[0028] Figure 6 is a frequency response curve comparison diagram of a micro loudspeaker with a radiation ring magnetic circuit and a conventional magnetic circuit loudspeaker of the present application;

[0029] Figure 7 is a cross-sectional view of a conventional magnetic circuit loudspeaker structure in the prior art;

[0030] Figure 8 is a structure diagram of a diaphragm of an embodiment of the present application.

[0031] Explanation of the attached drawings:

[0032] 10, outer shell; 11, bottom;

[0033] 12, outer ring wall; 13, accommodating cavity;

[0034] 14, positioning column; 15, hollow sound adjustment hole;

[0035] 16, circumferential sound adjustment hole; 17, solder pad;

[0036] 18, first sound adjustment net; 19, second sound adjustment net;

[0037] 20, magnetic circuit;

[0038] 21, inner ring magnetic circuit; 22, outer ring magnetic circuit;

[0039] 211, inner ring hole; 212, upper layer inner magnetic ring;

[0040] 213, middle inner magnetic ring; 214, lower layer inner magnetic ring;

[0041] 221, outer ring hole; 222, upper layer outer magnetic ring;

[0042] 223, middle outer magnetic ring; 224, lower layer outer magnetic ring;

[0043] 23, annular gap; 30, voice coil;

[0044] 31. Hollow tube; 32. Roll web;

[0045] 40. Diaphragm; 50. Iron shell;

[0046] 41. Dome; 42. Connecting part;

[0047] 43. Folded ring; 44. Outer ring;

[0048] 60. Magnet; 70. Washer;

[0049] 80. Diaphragm; 51. Tuning hole;

[0050] L1, inner diameter of the inner ring magnetic circuit; d2, wall thickness of the inner ring magnetic circuit;

[0051] d1, outer ring magnetic circuit wall thickness; L4, fold ring height;

[0052] L5, height of the dome; L6, inner diameter of the dome;

[0053] L7, inner diameter of the diaphragm; d4, outer diameter of the inner ring magnetic circuit;

[0054] d5, outer diameter of the outer ring magnetic circuit. Detailed Implementation

[0055] Please refer to Figures 1 to 8 As shown, it illustrates the specific structure of an embodiment of the present invention.

[0056] In the description of this invention, it should be noted that directional terms such as "up," "down," "front," "back," "left," and "right" indicate the orientation and positional relationship based on the accompanying drawings or the orientation or positional relationship shown during normal wear and use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this invention.

[0057] A miniature loudspeaker with a radiating magnetic circuit includes a housing 10, a magnetic circuit 20, a voice coil 30, and a diaphragm 40, wherein:

[0058] The outer shell 10 comprises a bottom 11 and an outer ring wall 12, the bottom 11 and the outer ring wall 12 constitute a containing cavity 13, the diaphragm 40, the voice coil 30 and the magnetic circuit 20 are installed in the containing cavity 13 of the outer shell 10, the bottom 11 of the outer shell 10 is provided with a positioning column 14 in the containing cavity 13, the positioning column 14 has a hollow passage penetrating through the bottom of the outer shell 10, the hollow sound hole 15 is arranged at the position corresponding to the hollow passage of the bottom of the outer shell, the hollow sound hole 15 is communicated with the hollow passage, and a plurality of circumferential sound holes 16 are arranged along the outer periphery of the hollow sound hole 15 and penetrating through the bottom 11 of the outer shell 10. The circumferential sound hole 16 is communicated with and opposite to the annular gap 23 to form a sound adjusting passage; the hollow sound hole 15 is opposite to the diaphragm 40 to form another sound adjusting passage. In this way, in the loudspeaker with the same outer diameter size, the sound adjusting passage is designed at the position of the inner magnetic ring center and the annular gap, which can effectively increase the size of the magnetic circuit and the voice coil, improve the BL value of the loudspeaker, improve the frequency response characteristics, thereby improving the sensitivity of the loudspeaker and producing good sound effect.

[0059] Preferably, the outer shell 10 has a solder pad 17 which is integrally injection molded with the outer shell 10. The problem of abnormality of the conventional loudspeaker shell pasting PCB is solved, and the process of bonding PCB is saved, thereby saving the production labor cost. Preferably, the bottom 11 of the outer shell 10 is provided with a first sound adjusting net 18 and a second sound adjusting net 19 at positions corresponding to the hollow sound hole 15 and the circumferential sound hole 16, respectively.

[0060] The outer ring wall 12 of the outer shell 10 is further recessed with an annular positioning groove, and the micro loudspeaker with the radiation ring magnetic circuit further comprises a copper ring, and the outer ring part is fixed in the annular positioning groove through the copper ring.

[0061] The magnetic circuit 20 comprises an inner ring magnetic circuit 21 and an outer ring magnetic circuit 22, and preferably, the inner diameter L1 of the inner ring magnetic circuit is 2.5mm-3.5mm. Preferably, the ratio of the wall thickness d2 of the inner ring magnetic circuit and the wall thickness d1 of the outer ring magnetic circuit is between 2 / 3 and 1, so that the magnetic leakage is not easy. The inner ring magnetic circuit 21 has an inner ring hole 211, and the outer ring magnetic circuit 22 has an outer ring hole 221, the inner ring magnetic circuit 21 is sleeved on the positioning column 14 through the inner ring hole 211, the outer ring magnetic circuit 22 is sleeved outside the inner ring magnetic circuit 21 through the outer ring hole 221, and the outer wall of the inner ring magnetic circuit 21 and the inner wall of the outer ring magnetic circuit 22 form an annular gap 23.

[0062] The hollow channel is opposite to the diaphragm 40 and forms another sound tuning channel together with the diaphragm 40 and the hollow channel. The annular gap 23 is 0.4mm-1.0mm, when the material grade of the inner ring magnetic circuit 21 and the outer ring magnetic circuit 22 is N52, the annular gap 23 between the inner ring magnetic circuit 21 and the outer ring magnetic circuit 22 is 0.4mm, and the BL value thereof is 1.4006; when the material grade of the inner ring magnetic circuit 21 and the outer ring magnetic circuit 22 is N52, the annular gap 23 between the inner ring magnetic circuit 21 and the outer ring magnetic circuit 22 is 0.7mm, and the BL value thereof is 1.0792; when the material grade of the inner ring magnetic circuit 21 and the outer ring magnetic circuit 22 is N52, the annular gap 23 between the inner ring magnetic circuit 21 and the outer ring magnetic circuit 22 is 1.0mm, and the BL value thereof is 0.82816; in the embodiment, the BL values generated by different annular gaps between the inner ring magnetic circuit 21 and the outer ring magnetic circuit 22 are obtained by Comsol software simulation, which is well known to those skilled in the art, and will not be described here.

[0063] Preferably, the inner ring magnetic circuit 21 is composed of the upper inner magnetic ring 212, the middle inner magnetic ring 213 and the lower inner magnetic ring 214 in sequence, and the outer ring magnetic circuit 22 is composed of the upper outer magnetic ring 222, the middle outer magnetic ring 223 and the lower outer magnetic ring 224 in sequence. Moreover, the magnetic lines of the upper outer magnetic ring 222, the upper inner magnetic ring 212, the middle inner magnetic ring 213 and the middle outer magnetic ring 223 form a closed magnetic loop, and the magnetic lines of the lower outer magnetic ring 224, the lower inner magnetic ring 214, the middle inner magnetic ring 213 and the middle outer magnetic ring 223 form a closed magnetic loop.

[0064] The end magnetic pole of the upper outer magnetic ring 222 adjacent to the middle outer magnetic ring 223 is the same as that of the lower outer magnetic ring 224, the end magnetic pole of the upper inner magnetic ring 212 adjacent to the middle inner magnetic ring 213 is the same as that of the lower inner magnetic ring 214, and the end magnetic pole of the upper outer magnetic ring 222 close to the diaphragm 40 is opposite to that of the upper inner magnetic ring 212 close to the diaphragm 40.

[0065] The end magnetic pole of the middle outer magnetic ring 223 close to the voice coil 30 is opposite to that of the middle inner magnetic ring 213 close to the voice coil 30, and the end magnetic pole of the upper outer magnetic ring 222 close to the diaphragm 40 is opposite to that of the middle outer magnetic ring 223 close to the voice coil 30.

[0066] Wherein, as Figure 4As shown, one end of the upper outer magnetic ring 222 and the lower outer magnetic ring 224 adjacent to the intermediate outer magnetic ring 223 is a S-pole, one end of the upper inner magnetic ring 212 and the lower inner magnetic ring 214 adjacent to the intermediate inner magnetic ring 213 is a N-pole, one end of the upper outer magnetic ring 222 adjacent to the diaphragm 40 is a N-pole, one end of the upper inner magnetic ring 212 adjacent to the diaphragm 40 is a S-pole, one end of the intermediate outer magnetic ring 223 adjacent to the voice coil 30 is a S-pole, and one end of the intermediate inner magnetic ring 213 adjacent to the voice coil 30 is a N-pole. Preferably, the upper inner magnetic ring 212, the intermediate inner magnetic ring 213, the lower inner magnetic ring 214, the upper outer magnetic ring 222, the intermediate outer magnetic ring 223, and the lower outer magnetic ring 224 are all annular structures closed as a whole. By adopting the structure that the upper layer, the intermediate layer, and the lower layer are all magnets in the inner magnetic circuit 21 and the outer magnetic circuit 22, compared with the traditional magnetic circuit, the magnetic field strength provided by the magnetic circuit 20 of the present application is greater according to actual measurement.

[0067] In addition, in the magnetic circuit 20, the inner magnetic circuit 21 adopts the design that the upper inner magnetic ring 212 and the lower inner magnetic ring 214 sandwich the intermediate inner magnetic ring 213, and the outer magnetic circuit 22 adopts the design that the upper outer magnetic ring 222 and the lower outer magnetic ring 224 sandwich the intermediate outer magnetic ring 223, wherein the upper inner magnetic ring 212, the lower inner magnetic ring 214, the upper outer magnetic ring 222, and the lower outer magnetic ring 224 are axial magnetic rings, and the intermediate inner magnetic ring 213 and the intermediate outer magnetic ring 223 are radial magnetic rings, which can further increase the strength of the magnetic field, not only can avoid the fracture of the axial magnet during the magnetization process, but also the upper inner magnetic ring 212 and the lower inner magnetic ring 214 are designed as a one-to-one corresponding magnetic ring structure with the intermediate inner magnetic ring 213, which is more conducive to the assembly of the entire magnetic circuit system, and the adjacent intermediate inner magnetic ring 213 and the intermediate outer magnetic ring 223 are radial magnetic rings, which has small magnetic leakage compared with the magnetic tile structure, does not need to splice the magnetic tile, and also solves the problem of unevenness between the magnetic tiles during assembly, thereby reducing the operation difficulty during the production of the loudspeaker.

[0068] Preferably, the upper inner magnetic ring 212, the intermediate inner magnetic ring 213, and the lower inner magnetic ring 214, the upper outer magnetic ring 222, the intermediate outer magnetic ring 223, and the lower outer magnetic ring 224 are all neodymium-iron-boron magnets. They have high magnetic properties and are the best magnetic properties in the creation of strong magnetic fields as practical magnets. The material grade of the neodymium-iron-boron magnet is N35-N52.

[0069] Preferably, the residual magnetism of the upper inner magnetic ring 212, the residual magnetism of the lower inner magnetic ring 214 are respectively less than the residual magnetism of the middle inner magnetic ring 213, and the residual magnetism of the upper inner magnetic ring 212 and the lower inner magnetic ring 214 superimposed is greater than the residual magnetism of the middle inner magnetic ring 213; the residual magnetism of the upper outer magnetic ring 222, the residual magnetism of the lower outer magnetic ring 224 are respectively less than the residual magnetism of the middle outer magnetic ring 223, and the residual magnetism of the upper outer magnetic ring 222 and the lower outer magnetic ring 224 superimposed is greater than the residual magnetism of the middle outer magnetic ring 223, which makes full use of the characteristics of the middle magnet magnetic conduction, so that the magnetic field strength is larger, and the size of the magnet and the horn is not increased.

[0070] The voice coil 30 is installed in the annular gap 23, the voice coil 30 includes a hollow tube 31 and a coil 32 located outside the hollow tube 31, and the coil 32 is located in the annular gap 23, wherein through the design of the hollow tube and the coil, the large amplitude space requirement of the horn is ensured, and the height of the coil 32 is not too high and the mass of the voice coil 30 is reduced, so that the horn has higher sensitivity.

[0071] The micro-horn magnetic circuit of the application adopts a non-iron design, uses the middle inner magnetic ring 213 and the middle outer magnetic ring 223 to replace the T iron and the air gap of the conventional magnet, and the middle inner magnetic ring 213 and the middle outer magnetic ring 223 with the magnetic field direction can better guide the magnetic field of the upper outer magnetic ring 222 and the lower outer magnetic ring 224, the upper inner magnetic ring 212 and the lower inner magnetic ring 214 together, so that the magnetic force lines of the magnetic field are more concentrated in the annular gap 23, and the non-iron design can reduce the eddy current generated by the magnetic circuit, thereby increasing the BL of the horn and the sensitivity.

[0072] The diaphragm 40 is installed above the voice coil 30 and combined with the top of the hollow tube 31, preferably, the coil 32 is located in the annular gap 23 between the middle inner magnetic ring 213 and the middle outer magnetic ring 223, and the height of the coil 32 is less than or equal to the thickness of the middle inner magnetic ring 213 and the middle outer magnetic ring 223, so that the radial magnetic circuit can effectively pass through the coil 32, thereby improving the BL value of the horn and enhancing the sensitivity.

[0073] As Figure 8As shown, the diaphragm 40 includes a spherical top 41, a connecting portion 42, a folded ring 43, and an outer ring portion 44 connected in sequence from inside to outside, the voice coil 30 is connected to the connecting portion 42, the diaphragm 40 is fixed to the outer shell 10 through the outer ring portion 44, the ratio of the spherical top inner diameter L6 to the diaphragm inner diameter L7 is between 50%-60%, and the folded ring height L4 is between 0.4mm-0.5mm. Preferably, the spherical top height L5 is between 0.3-0.45mm, and is not higher than the height of the folded ring. The spherical top 41 is made of light and high-hardness materials such as diamond-like carbon film, LCP liquid crystal polymer, graphene, and fiber paper, so that the high-frequency extension of the loudspeaker of the application is good, the sensitivity is high, the high sound performance is better, and the sound pressure is about 40% higher than that of ordinary loudspeakers. Therefore, the loudspeaker resonance frequency reaches 180-250Hz, the high frequency reaches 30KHz, and both high and low frequencies are considered, 20Hz-20KHz have good sound effect, and the folded ring 43 in this height range can reduce distortion, and the loudspeaker has a lower resonance frequency. If the folded ring height L4 is less than 0.4mm, the distortion is too much, and if the folded ring height is higher than 0.5mm, the resonance frequency is high and the low frequency difference is large.

[0074] As Figure 5 shown, it is a micro loudspeaker with a radiation ring magnetic circuit of the application and Figure 7 a conventional magnetic circuit loudspeaker, wherein the curve on the upper side is the BL test value curve of the micro loudspeaker with a radiation ring magnetic circuit of the application, and the other curve is the BL test value curve of the conventional magnetic circuit loudspeaker, as Figure 5 shown, the BL test value of the micro loudspeaker with a radiation ring magnetic circuit of the application is higher than Figure 7 the BL test value of the conventional magnetic circuit loudspeaker by more than 40%.

[0075] As Figure 6 shown, it is a micro loudspeaker with a radiation ring magnetic circuit of the application and Figure 7 a conventional magnetic circuit loudspeaker, wherein the curve on the upper side is the BL test value curve of the micro loudspeaker with a radiation ring magnetic circuit of the application, and the other curve is the BL test value curve of the conventional magnetic circuit loudspeaker, as Figure 6 shown, the BL test value of the micro loudspeaker with a radiation ring magnetic circuit of the application is higher than Figure 7 the BL test value of the conventional magnetic circuit loudspeaker by more than 40%.

[0076] The loudspeaker is applied with 1mW power, and the IEC711 artificial ear is used to test with the same test fixture matching the IEC711 artificial ear, the outer diameter size of the loudspeaker is 13.6mm, the magnet brand is N52, the outer ring magnetic circuit outer diameter d5=10.15mm, the inner ring magnetic circuit outer diameter d4=5.95mm, the annular gap 23=0.675mm, the outer ring magnetic circuit wall thickness d1=1.425mm, and the inner ring magnetic circuit wall thickness d2=1.425mm; wherein, the curve located at the upper side is the frequency response curve of the micro loudspeaker with the radiation ring magnetic circuit, and the other curve is the frequency response curve of the conventional magnetic circuit loudspeaker, so that the Y-axis value of the micro loudspeaker with the radiation ring magnetic circuit is higher than that of the conventional magnetic circuit loudspeaker in the loudspeaker with the same outer diameter size, and the sensitivity of the micro loudspeaker with the radiation ring magnetic circuit is higher than that of the conventional magnetic circuit loudspeaker, so as to produce a good sound effect.

[0077] The design of the present application focuses on that the inner ring magnetic circuit and the outer ring magnetic circuit are constructed into a radiation ring magnetic circuit, the coil width of the voice coil extends into the annular gap of the inner ring magnetic circuit and the outer ring magnetic circuit, the circumferential tuning hole is communicated with the annular gap and faces the annular gap to form a tuning channel, the hollow channel faces the diaphragm and forms another tuning channel together with the diaphragm, the tuning channels are respectively designed in the positioning column of the inner ring hole of the inner ring magnetic circuit and the position corresponding to the annular gap between the inner ring magnetic circuit and the outer ring magnetic circuit, so that the magnetic circuit and the coil size can be effectively increased in the loudspeaker with the same outer diameter size, the BL value of the loudspeaker is improved, the frequency response characteristic is improved, the sensitivity of the loudspeaker is improved, and a good sound effect is produced.

[0078] In addition, the voice coil is connected to the connecting portion, the diaphragm is fixed to the outer shell through the outer ring portion, the ratio of the ball top inner diameter to the diaphragm inner diameter is between 50%-60%, and the folding ring height is between 0.4mm-0.5mm, so that the loudspeaker resonance frequency reaches 180-250Hz, the high frequency reaches 30KHz, the high frequency and the low frequency are considered at the same time, and the sound effect is good at 20Hz-20KHz.

[0079] The above is only a preferred embodiment of the present application, and does not limit the technical scope of the present application, so any slight modification, equivalent change and modification made according to the technical essence of the present application to the above embodiment still belongs to the scope of the technical solution of the present application.

Claims

1. A miniature loudspeaker with a radiating magnetic circuit, comprising a housing, a magnetic circuit, a voice coil, and a diaphragm, wherein the housing includes a bottom and an outer ring wall, the bottom and the outer ring wall forming a receiving cavity, and the diaphragm, voice coil, and magnetic circuit are installed in the receiving cavity of the housing, characterized in that: The diaphragm comprises a spherical top, a connecting part, a folded ring and an outer ring part connected in sequence from inside to outside, the voice coil is connected to the connecting part, the diaphragm is fixed to the outer shell through the outer ring part, the ratio of the inner diameter of the spherical top to the inner diameter of the diaphragm is between 50% and 60%, and the height of the folded ring is between 0.4 mm and 0.5 mm; The bottom of the outer shell is provided with a positioning column in the accommodating cavity, the positioning column has a hollow passage penetrating through the bottom of the outer shell, the bottom of the outer shell is provided with a hollow sound hole corresponding to the hollow passage, the hollow sound hole is communicated with the hollow passage, and a plurality of circumferential sound holes are arranged along the outer periphery of the hollow sound hole and penetrating through the bottom of the outer shell; The magnetic circuit comprises an inner ring magnetic circuit and an outer ring magnetic circuit, the inner ring magnetic circuit has an inner ring hole, the outer ring magnetic circuit has an outer ring hole, the inner ring magnetic circuit is sleeved on the positioning column through the inner ring hole, the outer ring magnetic circuit is sleeved outside the inner ring magnetic circuit through the outer ring hole, and the outer wall of the inner ring magnetic circuit and the inner wall of the outer ring magnetic circuit form an annular gap, wherein the inner ring magnetic circuit is composed of an upper inner magnetic ring, a middle inner magnetic ring and a lower inner magnetic ring in sequence, the outer ring magnetic circuit is composed of an upper outer magnetic ring, a middle outer magnetic ring and a lower outer magnetic ring in sequence, the upper inner magnetic ring, the lower inner magnetic ring, the upper outer magnetic ring and the lower outer magnetic ring are axial magnetic rings, the middle inner magnetic ring and the middle outer magnetic ring are radial magnetic rings, the magnetic lines of the upper outer magnetic ring, the upper inner magnetic ring, the middle inner magnetic ring and the middle outer magnetic ring form a closed magnetic loop, the magnetic lines of the lower outer magnetic ring, the lower inner magnetic ring, the middle inner magnetic ring and the middle outer magnetic ring form a closed magnetic loop, the circumferential sound hole is communicated with the annular gap and opposite to the annular gap to form a sound adjusting channel; The magnetic poles of the upper outer magnetic ring and the lower outer magnetic ring near one end of the middle outer magnetic ring are the same, the magnetic poles of the upper inner magnetic ring and the lower inner magnetic ring near one end of the middle inner magnetic ring are the same, the magnetic poles of the upper outer magnetic ring and the upper inner magnetic ring near one end of the diaphragm are opposite, the magnetic poles of the middle outer magnetic ring and the middle inner magnetic ring near one end of the voice coil are opposite, and the magnetic poles of the upper outer magnetic ring near one end of the diaphragm and the middle outer magnetic ring near one end of the voice coil are opposite; The residual magnetism of the upper inner magnetic ring and the residual magnetism of the lower inner magnetic ring are respectively smaller than the residual magnetism of the middle inner magnetic ring, and the residual magnetism of the upper inner magnetic ring and the lower inner magnetic ring is greater than the residual magnetism of the middle inner magnetic ring, and the residual magnetism of the upper outer magnetic ring and the residual magnetism of the lower outer magnetic ring are respectively smaller than the residual magnetism of the middle outer magnetic ring, and the residual magnetism of the upper outer magnetic ring and the lower outer magnetic ring is greater than the residual magnetism of the middle outer magnetic ring; The voice coil is installed in the annular gap, the voice coil comprises a hollow tube and a coil located outside the hollow tube, the coil is located in the annular gap, the coil is located between the middle inner magnetic ring and the middle outer magnetic ring in the annular gap, and the height of the coil is less than or equal to the thickness of the middle inner magnetic ring and the middle outer magnetic ring, the diaphragm is installed above the voice coil and combined with the top of the hollow tube, the hollow passage is opposite to the diaphragm and forms another sound adjusting channel together with the diaphragm.

2. The micro-horn with the radiating loop magnetic circuit according to claim 1, characterized in that: The upper inner magnetic ring, the middle inner magnetic ring, the lower inner magnetic ring, the upper outer magnetic ring, the middle outer magnetic ring and the lower outer magnetic ring are all integrated annular structures.

3. The micro-horn with the radiating loop magnetic circuit according to claim 1, characterized in that: The outer shell has a pad which is integrally injection molded with the outer shell.

4. The micro-horn with the radiating loop magnetic circuit according to claim 1, characterized in that: The annular gap is 0.4mm-1.0mm.

5. The micro-horn with the radiating loop magnetic circuit according to claim 1, characterized in that: The inner diameter of the inner ring magnetic circuit is 2.5mm-3.5mm.

6. The micro-horn with the radiating loop magnetic circuit according to claim 1, characterized in that: The outer shell bottom is respectively provided with a first tuning net and a second tuning net at positions corresponding to the hollow tuning hole and the circumferential tuning hole.

7. The micro-horn with the radiating loop magnetic circuit according to claim 1, characterized in that: The wall thickness ratio of the inner ring magnetic circuit and the outer ring magnetic circuit is between 2 / 3 and 1.

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