CN117061929A

CN117061929A - Acoustic output device

Info

Publication number: CN117061929A
Application number: CN202311155913.6A
Authority: CN
Inventors: 王传波
Original assignee: Shenzhen Dancing Future Technology Ltd
Current assignee: Shenzhen Dancing Future Technology Ltd
Priority date: 2023-09-07
Filing date: 2023-09-07
Publication date: 2023-11-14

Abstract

The invention discloses an acoustic output device, which comprises an acoustic output device and a shell, wherein the acoustic output device comprises a vibrating diaphragm and a magnetic circuit structure, one side of the vibrating diaphragm, which is far away from the magnetic circuit structure, is the front surface of the acoustic output device, and the opposite side is the back surface of the acoustic output device. The shell is used for placing the sound emitting device, and is connected with the sound emitting device to form a cavity, the space connected with the front surface is a front cavity, and the space connected with the back surface is a back cavity; the cavity is provided with a sound outlet component for transmitting sound generated by vibration of the vibrating diaphragm through the sound outlet component, and the rear cavity is an irregularly-shaped cavity. Reflection of the acoustically driven sound by the rear cavity causes resonance of the sound and standing waves, and the frequency of the standing waves formed in the rear cavity generates a larger sound intensity, which corresponds to the principle of resonance peaks on the frequency response curve of the rear cavity. The device is arranged into an irregular cavity, so that the standing wave frequency is increased, and the standing wave peak value moves backwards along a frequency response curve, so that a better silencing effect with the front cavity is achieved.

Description

Acoustic output device

Technical Field

The invention relates to the field of acoustics, in particular to an acoustic output device.

Background

Compared with the traditional in-ear or semi-in-ear earphone, the open acoustic output device has the characteristics of being far away from the auditory canal and not blocking the earmuffs, so that a user can obtain good music listening on one hand and obtain sound information of the external environment on the other hand, and the user can obtain good experience. Because the open acoustic output device has bigger leakage sound than the traditional earphone, privacy is easy to leak, the prior art mostly adopts the open hole on the acoustic cavity to form the acoustic dipole, thereby reducing the leakage sound of the far-field. As known from the acoustic dipole principle, in order to reduce the leakage of the far-field acoustic dipole, it is necessary to well control the amplitude and phase of the acoustic dipole in the far-field acoustic dipole, and thus very strict control is required to control parameters such as acoustic impedance of the acoustic cavity, the acoustic outlet and the acoustic outlet, but due to the size limitation of such acoustic output device, great difficulty is brought to controlling the parameters, so that the leakage of the far-field acoustic dipole is difficult to control.

The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Disclosure of Invention

In order to meet the above requirements, the present invention aims to provide an acoustic output device for optimizing far-field sound leakage and improving earphone tone quality.

In order to achieve the above purpose, the present invention adopts the following technical scheme:

an acoustic output device comprises an acoustic output device and a shell, wherein the acoustic output device comprises a vibrating diaphragm and a magnetic circuit structure, one side of the vibrating diaphragm, which is far away from the magnetic circuit structure, is the front surface of the acoustic output device, and the opposite side is the back surface of the acoustic output device; the shell is used for placing the sound emitting device, the shell and the sound emitting device are connected to form a cavity, the space where the shell is connected with the front surface of the sound emitting device is a front cavity, and the space where the shell is connected with the back surface of the sound emitting device is a back cavity; the cavity is provided with a sound outlet component for transmitting sound generated by vibration of the vibrating diaphragm through the sound outlet component; the rear cavity comprises a rear cavity front surface opposite to the plane where the vibrating diaphragm is located, and a first side surface, a second side surface, a third side surface and a fourth side surface which are connected around the rear cavity front surface, wherein the first side surface is opposite to the third side surface, and the second side surface is opposite to the fourth side surface; the rear cavity is an irregularly-shaped cavity, and at least one sound outlet hole is formed in at least one of the front surface, the first side surface, the second side surface, the third side surface and the fourth side surface of the rear cavity; and the included angle between at least one surface of the first side surface, the second side surface, the third side surface and the fourth side surface and the dihedral angle formed by the front surface of the rear cavity is larger than 90 degrees.

In an embodiment, at least one of the front face, the first side, the second side, the third side, and the fourth side of the rear cavity is non-planar.

In an embodiment, at least one of the front surface, the first side surface, the second side surface, the third side surface and the fourth side surface of the rear cavity comprises two non-parallel planes, and the two non-parallel planes and the adjacent planes form an inclined plane.

In an embodiment, at least one of the first side, the second side, the third side and the fourth side forms an inclined plane with the front surface of the rear cavity, and each inclined plane forms the same or different dihedral angle with the front surface of the rear cavity.

In an embodiment, the first side, the second side, the third side and the fourth side all form inclined planes with the front surface of the rear cavity, all the inclined planes are the same as the dihedral angles of the front surface of the rear cavity, the rear cavity forms a trapezoid-like table, and the ratio of the front surface of the rear cavity to the surface of the diaphragm in the rear cavity is between 0.4 and 0.9.

In an embodiment, an inner surface of at least one of the rear cavity front surface, the first side surface, the second side surface, the third side surface and the fourth side surface is a curved surface.

In an embodiment, the inner surface of at least one of the front face, the first side face, the second side face, the third side face and the fourth side face of the rear cavity is water-wave-shaped or mountain-like protrusions.

In one embodiment, the sound outlet component is provided with a sound guide tube.

In one embodiment, the sound guide tube faces the interior of the rear cavity.

In an embodiment, the second side surface and the fourth side surface are respectively provided with a sound outlet, the second side surface is provided with a main sound outlet, the fourth side surface is provided with an auxiliary sound outlet, and the auxiliary sound outlet is connected with a sound guide tube.

In an embodiment, the cross-sectional area of the sound guide tube gradually decreases from the sound outlet hole inwards along the rear cavity.

In an embodiment, the sound guide tube has a curved structure, one end of the sound guide tube is connected to the sound outlet, and the other end of the sound guide tube is curved towards the direction of the diaphragm.

In an embodiment, the curved portion of the sound guide tube faces the opening of the magnetic circuit structure.

In an embodiment, the sound emitting component is two sound emitting holes arranged in the rear cavity.

In an embodiment, the sound guide tube is disposed in a sound outlet hole with a small relative size of the two sound outlet holes.

In an embodiment, two sound outlet holes are respectively provided with a sound guide tube, and at least a part of the sound guide tubes extend out of the shell.

In an embodiment, at least one wave-blocking structure is disposed on the inner surface of at least one of the front face, the first side face, the second side face, the third side face and the fourth side face of the rear cavity, and the wave-blocking structure is a baffle or a protrusion.

In an embodiment, the plurality of wave-blocking structures are distributed at equal intervals, and gaps are formed among the wave-blocking structures.

In an embodiment, the housing surrounds the acoustic drive, and the gap between the rear cavity and the acoustic drive is less than 1mm.

In an embodiment, a filler is provided in the housing in the gap between the rear cavity and the acoustic drive.

Compared with the prior art, the invention has the beneficial effects that: the rear cavity is arranged in an irregular shape, is generally in a cube structure and consists of a surface where the vibrating diaphragm is located and five surfaces opposite to or adjacent to the surface where the vibrating diaphragm is located, wherein the five surfaces are all in a plane state and form a cavity together with the surface where the vibrating diaphragm is located. The sound generated by the diaphragm will generate reflection of sound on all five surfaces, and standing waves and resonance will be formed in the process. The back cavity is shaped into an irregular surface so as to change the reflection of sound between the original five surfaces on the cavity, thereby influencing standing waves and resonance in the cavity. In the scheme, in the process that the sound driven by the acoustics passes through the rear cavity and propagates outwards through the sound outlet component of the rear cavity, the reflection of the sound driven by the acoustics by the rear cavity can cause resonance and standing waves of the sound, and the frequency of the standing waves formed in the rear cavity can generate larger soundThe sound intensity corresponds to the resonance peak on the frequency response curve of the rear cavity. Combining a standing wave formula:c ₀ is the sound velocity in the air, f ₁ The standing wave frequency is n, which is an integer; the rear cavity is provided with at least one sound outlet hole on at least one of the five surfaces, sound generated by the vibrating diaphragm is transmitted out from the sound outlet hole through the rear cavity, in the process, the sound is reflected by the five surfaces of the rear cavity, and then is emitted Kong Chuanchu, and resonance and standing waves of the sound are caused in the process. The maximum distance among the distances from the center of the sound outlet to the five surfaces is L; based on the method, the shape of the cavity of the rear cavity is changed to be an irregular cavity, so that the purpose of reducing L is achieved, the standing wave frequency f is increased, the standing wave peak value moves backwards along a frequency response curve, and the better silencing effect with the front cavity is achieved.

The invention is further described below with reference to the drawings and specific embodiments.

Drawings

FIG. 1 is a schematic diagram of an acoustic output device according to the present invention;

FIG. 2 is a cross-sectional view of the structure of FIG. 1;

FIG. 3 is a rear cavity schematic view of the structure of FIG. 1;

FIG. 4 is a schematic diagram of another embodiment of an acoustic output device of the present invention;

FIG. 5 is a cross-sectional view of the structure of FIG. 4;

FIG. 6 is a schematic diagram of another embodiment of an acoustic output device of the present invention;

FIG. 7 is a schematic view of another angular cross-sectional configuration of the structure of FIG. 1;

FIG. 8 is a schematic view of the schematic view of FIG. 1 including a first beveled condition;

FIG. 9 is a schematic view of the schematic view of FIG. 1 including two inclined surfaces;

FIG. 10 is a schematic view of the schematic view of FIG. 1 including four inclined surfaces;

FIG. 11 is a schematic view of the structure of FIG. 1 including a state in which the inner surface of the rear cavity is non-curved;

FIG. 12 is a schematic view of the schematic view of FIG. 1 including a state in which the inner surface of the rear chamber is water-corrugated;

FIG. 13 is a schematic view of the structure of FIG. 1 including a state in which the inner surface of the rear cavity is mountain-shaped;

fig. 14 is a schematic view showing a state in which the schematic view of fig. 1 includes a sound guide tube;

fig. 15 is a schematic view of the construction diagram of fig. 1 in another state including a sound guide tube;

fig. 16 is a schematic view of the structure of fig. 1 illustrating another state including a sound guide tube;

FIG. 17 is a schematic view of the structure of FIG. 1 illustrating another state including a sound guide tube;

fig. 18 is a schematic view showing a state in which the schematic view of fig. 1 includes a guide Guan She placed on a first slope;

fig. 19 is a schematic view of the structure of fig. 1 including a state in which the sound guide tube arrangement extends to the outside of the housing;

FIG. 20 is a schematic view of the schematic view of FIG. 1 including a baffle;

FIG. 21 is a schematic view of the schematic view of FIG. 1 including a stud;

FIG. 22 is a schematic view of the schematic view of FIG. 1 including a second rear chamber;

fig. 23 is a schematic view of the schematic view of fig. 1 without the rear chamber.

Reference numerals

101. Vibrating diaphragm 102 magnetic circuit structure

103. Acoustic drive 104 housing

105. Anterior cavity 106 posterior cavity

107. First side wall 108 end wall

109. Second side wall of first sound outlet 110

111. First inclined plane 112 second inclined plane

113. Fourth inclined plane of second sound outlet 114

115. Baffle plate of sound guide tube 116

117. The boss 118 second rear cavity

119. Fourth end wall of third side wall 120

1011 folded ring 1031 voice coil

1032 speaker 1033 speaker support

1034. Magnetic conduction plate 1035 magnet

1036. Washer 1037 sound outputting position

1041. First side of sound outlet 1071

1081. Rear cavity front 1101 second side

1191. Third side 1201 fourth side

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to fall within the scope of the invention.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be attached, detached, or integrated, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present invention, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms should not be understood as necessarily being directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Further, one skilled in the art can engage and combine the different embodiments or examples described in this specification.

As shown in fig. 1-23, the present invention proposes an acoustic output device, which includes an acoustic output device, where the acoustic output device includes a diaphragm 101, a magnetic circuit structure 102, and an acoustic driver 103, and the acoustic driver 103 includes a voice coil 1031, a speaker 1032, a speaker bracket 1033, a magnetic plate 1034, a magnet 1035, and a washer 1036, where the acoustic driver 103 is provided with two upper and lower acoustic output positions 1037 to enable sound to reach a rear cavity 106. The diaphragm 101 includes a bellows 1011. The side of the diaphragm 101 away from the magnetic circuit structure 102 is the front surface of the sound emitting device, and the opposite side is the back surface of the sound emitting device. The shell 104 is used for placing the sound emitting device, and is connected with the sound emitting device to form a cavity, the space connected with the front surface is a front cavity 105, and the space connected with the back surface is a back cavity 106. The cavity is provided with a sound outlet component 1041, at least one of the front cavity 105 and the rear cavity 106 is provided with the sound outlet component 1041, the number of the sound outlet components 1041 is one or more, the sound outlet component 1041 is a sound outlet hole and/or a sound guide tube, and the sound outlet component 1041 is used for transmitting sound generated by vibration of the vibrating diaphragm 101. Wherein the rear cavity 106 is an irregularly shaped cavity.

Preferably, at least one sound outputting position 1037 is disposed on the magnetic circuit structure 102, and sound generated by the diaphragm 101 is firstly transmitted through the sound outputting position 1037 and then transmitted through the sound outputting component 1041 on the cavity of the rear cavity 106.

The rear cavity 106 is a space cube, and the plane where the diaphragm 101 is located and the remaining five planes form the rear cavity together. In this solution, the plane of the diaphragm 101 is similar to the prior art, and the shape of the rear cavity is changed by changing the remaining five surfaces of the rear cavity 106, so that the rear cavity is called as an irregularly-shaped cavity. The main design point of the scheme is to change the shape of the cavity to achieve the purpose of changing the sound effect, and the position expression of each surface in the cavity is used for facilitating explanation of the technical scheme and is not limiting on the position and the name of each surface. Referring to fig. 2 and 3, for convenience of description, five surfaces are defined, in the rear cavity 106, a surface opposite to a plane in which the diaphragm 101 is located is referred to as a rear cavity front surface 1081, a side housing in which the rear cavity front surface 1081 is located is an end wall 108, an upward-facing surface (or a surface defined as a surface near a top of a user's head in the earphone sound generating part) of the remaining four surfaces is a first side surface 1071, and based on the first side surface 1071, a second side surface 1101 (the second side surface 1101 is located at an inner surface of the second side wall 110) and a third side surface 1191 (the third side surface 1191 is located at an inner surface of the third side wall 119) and a fourth side surface 1201 (the fourth side surface is located at an inner surface of the fourth end wall 120) are respectively in a counterclockwise direction with reference to the surface of the diaphragm 101 to the rear cavity front surface 1081. Wherein the first side 1071 is opposite the third side 1191 and the second side 1101 is opposite the fourth side 1201.

As shown in fig. 1, 2 and 3, the rear cavity 106 is elliptical in cross-section.

As shown in fig. 4 and 5, in the present embodiment, the rear chamber 106 has a rectangular parallelepiped shape with a chamfer.

As shown in fig. 6, in the present embodiment, the rear chamber 106 is rectangular parallelepiped in shape.

The shape of one or more of the five surfaces is changed, so that the shape of the whole cavity is changed. In the process that the sound of the sound emitting device passes through the rear cavity 106 and propagates outwards through the sound emitting component of the rear cavity 106, the reflection of the sound of the acoustic driving 103 by the rear cavity 106 can cause resonance and standing waves of the sound, and the frequency of the standing waves formed in the rear cavity can generate larger sound intensity and corresponds to resonance peaks on the frequency response curve of the rear cavity. According to the standing wave formula:wherein L is the length of the long side of the rear cavity, c ₀ Is the sound velocity in the air, f ₁ And n is an integer for standing wave frequency.

Wherein, L is more specifically explained as that the rear cavity 106 is provided with at least one sound outlet hole on at least one of the five surfaces, the sound generated by the diaphragm 101 is transmitted from the sound outlet member 1041 through the cavity of the rear cavity 106, in the process, the sound is reflected by the five surfaces of the cavity of the rear cavity 106 and then transmitted from the sound outlet member 1041, and the process causes resonance and resonance of the soundStanding waves. The maximum distance among the distances from the center position of the sound emitting member 1041 to the five surfaces is L. Based on the above, the purpose of reducing L is achieved by changing the shape of the sound outlet and the cavity, thereby leading the standing wave frequency f ₁ The standing wave peak is shifted backward along the frequency response curve.

As shown in fig. 8, in this embodiment, a first sound outlet 109 is formed at a connection position between a first side wall 107 where the first side 1071 is located and an end wall 108 where the rear cavity front 1081 is located, and a first inclined surface 111 is formed on a portion of the first side wall 107 or the end wall 108, so that a dihedral angle formed between the first side 1071 and the rear cavity front 1081 is greater than 90 °. Through this setting, first side 1071 contains two planes that are certain angle, and wherein the contained angle of the plane that links to each other with back chamber front 1081 and the dihedral angle of back chamber front 1081 is greater than 90 degrees, forms the inclined plane promptly between first side 1071 and back chamber front 1081, constitutes polygonal structure. When the rear cavity 106 is vertical between the faces, the rear cavity 106 is rectangular or square. And the first sound outlet 109 is formed on the first inclined surface 111. At this time, the surface farthest from the center of the first sound outlet 109 is the third side 1191, i.e., the bottom surface, but since the inclined surface is provided and the first sound outlet 109 is provided on the inclined surface, it is clear from the figure that the distance from the center point of the first sound outlet 109 to the third bottom surface, i.e., L in the formula, becomes smaller. The design can shorten the length of the long side on one hand, and the reference standing wave formula can increase f by shortening the length of the long side ₁ Standing wave frequency reaches the purpose that promotes tone quality, promotes tone quality. Meanwhile, the design reduces the area of the cavity, the smaller the volume of the rear cavity is, the more the resonance peak of the frequency response curve corresponding to the rear cavity is, and the better the silencing effect is.

As shown in fig. 8 and 9, in the present embodiment, the end wall 108 includes two mutually non-parallel planes, and the two mutually non-parallel planes and the adjacent planes form an inclined plane. Specifically, the second inclined surface 112 is formed on the third side wall 110 where the third side surface 1191 is located, and the second sound outlet hole 113 is provided on the second inclined surface 112, and at this time, at least two dihedral angles (angles are both greater than 90 °) formed with the front surface of the rear cavity 106 are included in this example. First sound outlet 1The size of 09 is greater than the size of second sound outlet 113, and first sound outlet 109 and second sound outlet 113 both play the effect of play sound, and second sound outlet 113 still plays pressure release and tuning's effect simultaneously. The positions of the first and second sound outlet holes 109 and 113 may be provided on the side wall or the inclined surface. The cross-sectional area of the second sound outlet 113 is not larger than that of the first sound outlet 109, the ratio of the cross-sectional area of the second sound outlet 113 to that of the first sound outlet 109 is 0.2-1, and the cross-sectional area of at least one sound outlet is not smaller than 0.25mm ² 。

In other embodiments, in order to further shorten the length of the long side and reduce the volume of the rear cavity 106, an inclined plane, i.e. the third inclined plane 113, is added to the plane of the first side 1071 and the diaphragm 101 based on the above scheme. In this way, the number of bevels is related to the number of faces constituting the rear cavity 106.

As shown in fig. 10, in the present embodiment, on the basis of fig. 9, the housing includes four inclined planes, which are respectively a first inclined plane 111, a second inclined plane 112, a third inclined plane 113, and a fourth inclined plane 114, to form four dihedral angles with the front face 1081 of the rear cavity, where the dihedral angles formed by the first inclined plane 111, the second inclined plane 112, the third inclined plane 113, and the fourth inclined plane 114 and the front face of the rear cavity are set identically or differently. In this embodiment, the inclination angle of the inclined plane and the ratio of the width of the projection of the inclined plane on the first side 1071 to the width of the first side 1071 have an influence on the overall design. The dihedral angle of the bevel with the rear cavity front face 1081 is between 90 degrees and 170 degrees, when the dihedral angle is 90 degrees, i.e., the first side 1071 is perpendicular to the rear cavity front face 1081. The ratio of the width of the projection of the inclined surface on the first side 1071 to the width of the first side 1071 is between 0.1 and 1, when the ratio is 1, i.e. the whole first side 1071 forms a certain inclination angle with the rear cavity front 1081, the first side 1071 is no longer composed of two sides. The sound emitting component 1041 may be disposed on a sidewall or an inclined plane of the rear cavity 106, where the sound emitting component 1041 is configured as a sound emitting hole.

In order to increase the sound range difference, in this embodiment, the sound outlet is provided on the inclined plane, and the sound generated by the vibration of the diaphragm 101 propagates to the outside through the sound outlet on the inclined plane after passing through the rear cavity 106. By adjusting the inclination angle of the inclined plane, the ratio of the projection width of the inclined plane and the first side 1071, the position of the sound outlet hole on the inclined plane and the size of the sound outlet hole, the value of L in the formula is reduced, the volume of the cavity of the rear cavity is reduced, and a better frequency response curve of sound transmitted to the outside by the rear cavity is obtained. In this scheme the inclined plane is not limited to smooth inclined plane, and the inclined plane inwards protrudes or outwards is sunken, and protruding or sunken of certain radian in back chamber direction all belongs to the protection scope of this scheme promptly.

In some embodiments, the chamfer may be curved inwardly or outwardly at an angle, or in an inwardly convex or outwardly concave configuration.

Based on fig. 4, 5 and 10, in this embodiment, all the inclined planes are the same as the dihedral angles of the front surface of the rear cavity, the rear cavity forms a trapezoid-like table, and the proportion of the front surface 1081 of the rear cavity to the surface of the diaphragm 101 in the cavity of the rear cavity 106 is between 0.4 and 0.9. To further shorten the length of the long side and reduce the volume of the rear cavity, a plurality of inclined planes are added, the rear cavity 106 is arranged as a polygon, the lengths and the inclined angles of the plurality of inclined planes can be the same or different, and the cavity can be arranged as a regular polygon or an irregular polygon. Still further, at least three of the first side 1071, the second side 1101, the third side 1191, and the fourth side 1201 form slopes with the rear cavity front 1081 that are the same or different dihedral angles with the rear cavity front 1081. One implementation is that the first side 1071, the second side 1101, the third side 1191, and the fourth side 1201 form inclined planes with the rear cavity front 1081 that are at the same dihedral angle as the rear cavity front 1081, i.e., the entire rear cavity 106 cavity is shaped like a trapezoid table.

As shown in fig. 11, in this embodiment, the inner surface of the end wall 108 where the rear cavity front face 1081 is located is provided as a non-planar surface, such as a curved surface, in such a way as to change the reflection of sound waves inside the rear cavity 106. The cavity is generally in a cube structure, and is formed by a surface of the diaphragm 101 and five surfaces opposite to or adjacent to the surface of the diaphragm 101, wherein the five surfaces are all in a plane state, and form the cavity together with the surface of the diaphragm 101. The sound generated by the diaphragm 101 will be reflected by all five surfaces, and standing waves and resonances will be formed in the process. By arranging the convex columns, the baffle plates or other structures on the inner surface of at least one of the five surfaces connected with the cavity, the reflection of sound on the original five surfaces of the cavity is changed, and the standing wave and resonance in the cavity are changed.

As shown in fig. 12 and 13, in the present embodiment, the inner surface of the end wall 108 is water-wave-like or mountain-like convex.

In other embodiments, based on fig. 12, 13, the inner surface of any one or more of the rear cavity front face 1081, the first side 1071, the second side 1101, the third side 1191, and the fourth side 1201 is water-wave-like or mountain-like convex. By arranging the five faces into an irregular shape from a plane, the shape of the entire rear cavity is changed.

In other embodiments, the five outer surfaces of the rear cavity 106 are planar, and at least one of the inner surfaces is provided with water-wave-like or mountain-like protrusions, compressing the volume of the cavity and changing the length of the long side. Changing the length of the long side in the rear cavity 106 can change the standing wave frequency according to the standing wave formula. The shape of the long side is changed, so that resonance and standing waves of the rear cavity 106 are changed, and meanwhile, the space of the rear cavity 106 can be reduced according to the changed shape of the long side, so that a better frequency response curve is obtained.

As shown in fig. 14, in the present embodiment, the sound outlet is provided with a sound guide tube 115, and the sound guide tube 115 faces the rear cavity.

As shown in fig. 15, in the present embodiment, the first side surface and the third side surface are respectively provided with a first sound outlet 109 and a second sound outlet 113, the first sound outlet 109 is a main sound outlet, the second sound outlet 113 is a sub sound outlet, and the sub sound outlet is connected to a sound guide tube 115.

Based on the state shown in fig. 15, in order to obtain a better sound effect, a multi-sound outlet design is adopted. Preferably, a design with double sound outlet holes is adopted, one sound outlet hole is a main sound outlet hole, one sound outlet hole is an auxiliary sound outlet hole, the auxiliary sound outlet hole is also called a pressure release hole or a tuning hole, and the two sound outlet holes together play the purpose of adjusting the frequency response curve of the sound outlet of the rear cavity. The size of the main sound outlet hole is larger than that of the auxiliary sound outlet hole, so that a further tuning effect is achieved.

In this embodiment, in order to form an acoustic dipole with the sound outlet of the front cavity 105, the rear cavity 106 is provided with at least one sound outlet to cancel far-field leakage. The sound outlet hole may be formed on any one of the five surfaces of the rear cavity surface, so as to meet the actual production requirement and better sound outlet effect, the sound outlet Kong Kaishe is generally formed on the second side 1101 and/or the fourth side 1201, and the L is reduced to achieve the better sound outlet effect. A sound guide pipe is arranged at the fourth side 1201 of the sound outlet hole of the rear cavity 106, and is connected with the sound outlet hole, and the sound guide pipe faces the inside of the rear cavity 106 and is used for transmitting the sound generated by the diaphragm 101 in the rear cavity 106 to the outside through the sound guide pipe 115. On the one hand, the space structure of the rear cavity 106 can be changed, and the resonance and standing wave of the rear cavity 106 can be changed by arranging the sound guide tube 115 at the sound outlet of the rear cavity 106. On the other hand, the frequency response of the sound at the sound outlet can be changed, and when the sound speed is high, the sound can generate frequency response noise, and the sound guide tube 115 is arranged at the sound outlet, so that the frequency response can be improved.

As shown in fig. 15, in the present embodiment, the cross-sectional area of the sound guide tube 115 gradually decreases from the second sound outlet hole 113 inward along the rear cavity.

As shown in fig. 16, in the present embodiment, the sound guide tube 115 has a curved structure, and one end of the sound guide tube 115 is connected to the sound outlet hole, and the other end is curved toward the diaphragm 101. The bent portion of the sound guide tube 115 faces the opening of the magnetic circuit structure. The propagation of sound in the rear cavity is further changed, and better frequency response curves can be obtained by sound transmitted through the rear cavity.

As shown in fig. 17, in the present embodiment, two sound outlets formed in the first side 1071 and the third side 1191 are both provided with sound guide tubes 115.

As shown in fig. 18, in the present embodiment, when the first side 1071 is provided with an inclined surface, the sound outlet hole is provided with a sound guide tube 115.

As shown in fig. 19, in this embodiment, at least a part of the sound guide 115 protrudes out of the case 104, and the portion protruding out of the fourth side 1201 corresponds to a baffle between the front sound source and the back sound source of the diaphragm 101, which increases the sound difference between the two sounds without much influence on far-field sound, and the cancellation effect of the in-ear sound is reduced due to the increased sound path difference for the in-ear speaker, thereby enhancing the in-ear sound intensity.

As shown in fig. 20 and 21, in the present embodiment, at least one wave-blocking structure is disposed on the front surface 1081 of the rear cavity, wherein at least one wave-blocking structure is disposed on the inner surface of at least one of the front surface 1081 of the rear cavity, the first side 1071, the second side 1101, the third side 1191, and the fourth side 1201, and the wave-blocking structure is the baffle 116 or the protrusion 117.

As shown in fig. 21, in this embodiment, a plurality of the studs 117 are distributed at equal intervals, and gaps are provided between the studs 117. The preferred studs 117 are equally spaced. The gaps between the posts 117 change the overall structure of the rear cavity and reduce the effects of standing waves and resonances in the rear cavity on the sound effects of the rear cavity. The stud may be hollow or solid in construction. The plurality of studs may be provided on a single face, for example on the inner surface of the second side only.

Preferably, the protrusion, for example, the position of the sound outlet hole may be set according to a specific situation, and when the sound outlet hole is disposed on the fourth side, the sound outlet hole is farthest from the second side according to the structure of the rear cavity, that is, L in the above standing wave formula, that is, the second side has the greatest influence on the standing wave and resonance of the sound generated by the diaphragm, so that at least one protrusion is disposed on the inner surface of the second side to change the standing wave and resonance of the cavity. When the rear cavity is provided with a plurality of sound outlet holes, the reflection of sound can be changed by arranging the convex columns according to the judgment of which surface is the most influenced surface of standing waves and resonance of sound generated by the vibrating diaphragm. To change the standing wave and resonance of the cavity.

When a plurality of projections are provided on the inner surfaces of the five faces, the projections may be arranged at equal intervals or may be arranged at random, and preferably the projections are arranged at equal intervals. Because of the gap between the convex column structure and the convex column, the integral structure of the cavity is changed, and the influence of standing waves and resonance in the cavity on the sound effect of the rear cavity can be reduced.

As shown in fig. 20, in the present embodiment, when a plurality of baffles 116 are provided, the plurality of baffles 116 may be equally spaced or randomly distributed.

Based on fig. 20, in the present embodiment, the plurality of baffles 116 are perpendicular to the side wall, the lengths of the plurality of baffles are the same, the baffles are distributed at equal intervals, that is, small cavities are formed between the baffles at equal intervals, and resonance and standing waves of sound in the rear cavity are changed by using the baffles and the small cavities.

In another embodiment, based on fig. 20, the length of the baffles 116 and the spacing between the baffles are set to be different, and by changing the length of the different baffles and the spacing between the baffles, different combinations of baffles and small cavities are combined, improving the resonance and standing wave of sound in the rear cavity.

In another embodiment, based on fig. 20, the baffle 116 is disposed at a certain inclination angle to the inner surface of the rear cavity, and a horn or inverted horn shape is formed between adjacent baffles.

In another embodiment, based on fig. 20, the bottom surfaces of different baffles 116 are connected to the side walls of the rear cavity, and the side surfaces of adjacent baffles are connected at an angle to form a honeycomb-like design, forming one or more small cavities, changing the original spatial structure of the rear cavity, and thus changing the original sound characteristics.

In another embodiment, based on FIG. 20, the baffles 116 are spaced apart to form a semi-enclosed honeycomb-like coal design. In this embodiment, the baffles are equally spaced or randomly distributed.

In one embodiment, as shown in fig. 22, a second rear cavity 118 is configured within the housing 104 to improve the resonance and standing wave of sound in the rear cavity by altering the original spatial configuration of the rear cavity 106.

In one embodiment, as shown in fig. 23, the casing 104 surrounds the acoustic driver 103 and the magnetic circuit structure 102, the width of the casing 104 is larger than the acoustic driver 103, the casing 104 is close to the acoustic driver, and the gap between the rear cavity 106 and the acoustic driver 103 is smaller than 1mm.

In some embodiments, the spacing between the rear cavity 106 and the acoustic driver 103 is 0, i.e., the housing 104 is in direct contact with the acoustic driver 103.

Preferably, a filler, such as a sponge or the like, may also be prevented as a buffer between the rear cavity 106 in the housing 104 and the spacing of the acoustic driver 103. Since the space between the housing 104 and the acoustic driver 103 is small, the space corresponding to the rear cavity 106 is small, and the rear cavity 106 is nearly vanished. The presence of the cavity in the rear cavity 106 affects the frequency response curve of the sound outlet of the rear cavity 106, and generally, the larger the volume of the rear cavity 106 is, the more forward the resonance peak of the frequency response curve of the sound of the rear cavity 106 is. According to the acoustic dipole principle adopted by remote silencing, the acoustic dipole is unfavorable for counteracting the front cavity 105 or the sound on the front surface, so that silencing is realized. Therefore, the scheme is as small as possible, is favorable for pushing the resonance peak backwards in the frequency response curve, and achieves better far-field silencing effect. Preferably, in this solution, the magnetic circuit structure 102 is not provided with a sound outlet, the sound outlet is provided on the sound outlet driving device 103, the casing 104 surrounding the sound outlet driving device 103 is provided with a sound outlet corresponding to the sound outlet provided on the sound outlet driving device 103, i.e. the side of the casing 104 is provided with a sound outlet visually, thus greatly reducing the volume of the cavity, and simultaneously, the space for opening holes is more, which is beneficial to obtaining better frequency response curve.

In summary, the rear cavity is configured in an irregular shape, and is generally in a cube structure, and is composed of a surface on which the diaphragm is located and five surfaces opposite to or adjacent to the surface on which the diaphragm is located, where the five surfaces are all in a planar state, and the five surfaces and the surface on which the diaphragm is located form the cavity together. The sound generated by the diaphragm will generate reflection of sound on all five surfaces, and standing waves and resonance will be formed in the process. The back cavity is shaped into an irregular surface so as to change the reflection of sound between the original five surfaces on the cavity, thereby influencing standing waves and resonance in the cavity. In the scheme, in the process that sound driven by the acoustics passes through the rear cavity and propagates outwards through the sound outlet component of the rear cavity, the resonance and standing wave of the sound can be caused by the reflection of the sound driven by the rear cavity, the frequency of the standing wave formed in the rear cavity can generate larger sound intensity, and the principle corresponds to the resonance peak on the frequency response curve of the rear cavity. Combining a standing wave formula:c ₀ is the sound velocity in the air, f ₁ The standing wave frequency is n, which is an integer; the rear cavity is provided with at least one sound outlet hole on at least one of the five surfaces, sound generated by the vibrating diaphragm is transmitted out from the sound outlet hole through the rear cavity, in the process, the sound is reflected by the five surfaces of the rear cavity, and then is emitted Kong Chuanchu, and resonance and standing waves of the sound are caused in the process. The maximum distance among the distances from the center of the sound outlet to the five surfaces is L; based on the method, the shape of the cavity of the rear cavity is changed to be an irregular cavity, so that the purpose of reducing L is achieved, the standing wave frequency f is increased, the standing wave peak value moves backwards along a frequency response curve, and the better silencing effect with the front cavity is achieved.

It will be apparent to those skilled in the art from this disclosure that various other changes and modifications can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. An acoustic output device comprises an acoustic output device and a shell, wherein the acoustic output device comprises a vibrating diaphragm and a magnetic circuit structure, one side of the vibrating diaphragm, which is far away from the magnetic circuit structure, is the front surface of the acoustic output device, and the opposite side is the back surface of the acoustic output device; the shell is used for placing the sound emitting device, the shell and the sound emitting device are connected to form a cavity, the space where the shell is connected with the front surface of the sound emitting device is a front cavity, and the space where the shell is connected with the back surface of the sound emitting device is a back cavity; the cavity is provided with a sound outlet component for transmitting sound generated by vibration of the vibrating diaphragm through the sound outlet component; the rear cavity comprises a rear cavity front surface opposite to the plane where the vibrating diaphragm is located, and a first side surface, a second side surface, a third side surface and a fourth side surface which are connected around the rear cavity front surface, wherein the first side surface is opposite to the third side surface, and the second side surface is opposite to the fourth side surface;

the method is characterized in that: the rear cavity is an irregularly-shaped cavity, and at least one sound outlet hole is formed in at least one of the front surface, the first side surface, the second side surface, the third side surface and the fourth side surface of the rear cavity; and the included angle between at least one surface of the first side surface, the second side surface, the third side surface and the fourth side surface and the dihedral angle formed by the front surface of the rear cavity is larger than 90 degrees.

2. The acoustic output device of claim 1, wherein at least one of the back cavity front, the first side, the second side, the third side, and the fourth side is non-planar.

3. The acoustic output device of claim 1, wherein at least one of the rear cavity front face, the first side face, the second side face, the third side face, and the fourth side face comprises two mutually non-parallel planes that form an inclined plane with an adjacent plane.

4. The acoustic output device of claim 1, wherein at least one of the first side, the second side, the third side, and the fourth side forms a bevel with the front face of the rear cavity, each of the bevels forming a dihedral angle with the front face of the rear cavity that is the same or different, respectively.

5. The acoustic output device of claim 1, wherein the first side, the second side, the third side, and the fourth side all form inclined planes with a front face of the rear cavity, all the inclined planes are identical to a dihedral angle of the front face of the rear cavity, the rear cavity forms a trapezoid-like mesa shape, and a ratio of the front face of the rear cavity to a face of the rear cavity where the diaphragm is located is between 0.4 and 0.9.

6. The acoustic output device of claim 2, wherein an inner surface of at least one of the back cavity front, the first side, the second side, the third side, and the fourth side is curved.

7. The acoustic output device of claim 2, wherein an inner surface of at least one of the rear cavity front face, the first side face, the second side face, the third side face, and the fourth side face is water-wave-like or mountain-like protrusions.

8. The acoustic output device of claim 1, wherein the sound outlet member is provided with a sound guide tube.

9. The acoustic output device of claim 8, wherein the sound guide tube faces the interior of the rear cavity.

10. The acoustic output device according to claim 8, wherein the second side surface and the fourth side surface are respectively provided with a sound outlet, the second side surface is provided with a main sound outlet, the fourth side surface is provided with a secondary sound outlet, and the secondary sound outlet is connected with a sound guide tube.

11. The acoustic output device of claim 10, wherein the cross-sectional area of the sound guide tube tapers inwardly from the sound outlet along the rear cavity.

12. The acoustic output device according to claim 10, wherein the sound guide tube has a curved structure, one end of the sound guide tube is connected to the sound outlet hole, and the other end of the sound guide tube is curved and faces the direction of the diaphragm.

13. The acoustic output device of claim 12, wherein the curved portion of the sound guide tube faces the opening of the magnetic circuit structure.

14. The acoustic output device of claim 8, wherein the sound outlet member is two sound outlet holes provided in the rear cavity.

15. The acoustic output device of claim 14, wherein the sound guide tube is disposed in a relatively small sized sound outlet of the two sound outlets.

16. An acoustic output device as claimed in claim 8 or 15, wherein sound ducts are provided at both of the sound outlet holes, at least a portion of the sound ducts extending outside the housing.

17. The acoustic output device of claim 1, wherein an inner surface of at least one of the rear cavity front face, the first side face, the second side face, the third side face, and the fourth side face is provided with at least one wave blocking structure, and the wave blocking structure is a baffle or a bump.

18. The acoustic output device of claim 17, wherein a plurality of the wave-blocking structures are equally spaced with gaps therebetween.

19. The acoustic output device of claim 1, wherein the housing surrounds the acoustic drive, and the gap between the rear cavity and the acoustic drive is less than 1mm.

20. The acoustic output device of claim 19, wherein a filler is disposed in the housing in a gap between the rear cavity and the acoustic driver.