A directional microphone

Abstract

The utility model provides a directivity microphone belongs to acoustics field, including circuit board, be equipped with MEMS sensor, ASIC chip, connecting gold wire and casing on the circuit board, the circuit board with first cavity is formed to casing, be equipped with first sound hole below MEMS sensor on the circuit board, be equipped with second sound hole on the circuit board or on the casing, still include second cavity, second cavity with second sound hole corresponds, second cavity is equipped with third sound hole, second cavity third sound hole with second sound hole forms first sound channel, first sound channel is labyrinth shape, the utility model discloses special cavity design, and the difference of sound path is increased to multi -damping to realize pressure difference structure, form directivity, the utility model MEMS monomer realizes the characteristic of directivity, is easier to save the whole machine space, the utility model design is simple, and the process is easy to realize.

Description

Technical Field

[0001] This utility model relates to a directional microphone. Background Technology

[0002] Directional microphones (MICs) are widely used in various consumer electronics products as directional sound pickup and noise cancellation solutions. Most of these directional microphones achieve this through pressure difference; typically, two holes are made on the microphone, and sound enters through two separate holes. The final directional characteristic is achieved through the difference in sound path and damping. Currently, traditional ECM products are more mature, while MEMS directional microphones are less commonly used.

[0003] Traditional ECM directional products have poor consistency, while MEMS products have better consistency. However, due to size and performance limitations, there are relatively few MEMS directional products in the industry, and most are implemented through modules, as shown in the attached figure. Figure 1 As shown, the circuit board has two sound holes, each corresponding to one of the two cavities. On the other side of the circuit board, the MEMS sensor, ASIC chip, connecting gold wires, and housing (corresponding to a standard MEMS microphone) are placed. Capacitors and resistors can also be placed on the circuit board for filtering. When sound travels from the 0° direction, it enters through the two sound holes and ultimately acts on the upper and lower surfaces of the MEMS diaphragm through internal paths. Through the path difference and damping, it exhibits directional characteristics. This design achieves directional sound, but its large size makes it difficult to use in space-constrained environments. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of the above-mentioned traditional technologies and provide a directional microphone.

[0005] The purpose of this utility model is achieved through the following technical measures: a directional microphone, including a circuit board, on which a MEMS sensor, an ASIC chip, connecting gold wires and a housing are provided, the circuit board and the housing form a first cavity, a first sound hole is provided on the circuit board below the MEMS sensor, and a second sound hole is provided on the circuit board or the housing, characterized in that: it further includes a second cavity, the second cavity corresponds to the second sound hole, the second cavity is provided with a third sound hole, the second cavity, the third sound hole and the second sound hole form a first sound channel, the first sound channel is maze-shaped.

[0006] As an improvement, a third cavity is also included, which corresponds to the first sound hole. The third cavity is provided with a fourth sound hole. The third cavity, the fourth sound hole, and the first sound hole form a second sound channel. The sound path length of the first sound channel is L1, and the sound path length of the second sound channel is L2, where L1>L2 or L1<L2.

[0007] As a further improvement, the second channel is maze-shaped.

[0008] As a further improvement, the second cavity is a labyrinthine cavity, located inside the first cavity, outside the first cavity, or in the body of the circuit board, and at least one first baffle is provided inside the second cavity and between the second sound hole and the third sound hole.

[0009] As a further improvement, it includes a plurality of first baffles, wherein the first baffles form a first channel with the inner wall of the second cavity or between two opposing first baffles, and adjacent first channels are staggered.

[0010] As a further improvement, it includes a plurality of first baffles, each of which is provided with a second channel, and the second channels between adjacent first baffles are staggered.

[0011] As a further improvement, it includes a plurality of first baffles, the first baffles being in a labyrinthine shape, with the third channel formed between two opposing first baffles, the third channels being interconnected with each other, one end of the third channel being connected to the second sound hole and the other end being connected to the third sound hole.

[0012] As a further improvement, the third cavity is a labyrinthine cavity, which is located inside the first cavity, outside the first cavity, or in the body of the circuit board; at least one second baffle is provided in the third cavity and between the first sound hole and the fourth sound hole.

[0013] As a further improvement, it includes a plurality of second baffles, wherein the second baffles form a fourth channel with the inner wall of the third cavity or between two opposing second baffles, and adjacent fourth channels are staggered.

[0014] As a further improvement, it includes a plurality of second baffles, each of which is provided with a fifth channel, and the fifth channels between adjacent second baffles are staggered.

[0015] As a further improvement, it includes a plurality of second baffles, the second baffles being in a labyrinthine shape, with the sixth channel formed between two opposing second baffles, the sixth channel being interconnected with each other, one end of the sixth channel being connected to the first sound hole and the other end being connected to the fourth sound hole.

[0016] Due to the adoption of the above technical solution, the advantages of this utility model compared with the prior art are: First: This new type of instrument uses a special cavity design and multiple damping to increase the sound path difference, realize a pressure difference structure, and form directivity; Second: The directivity of this new type is customizable and the adjustment is more flexible. In addition to the second sound hole, the third sound hole and the damping mesh on the circuit board, the cavity corresponding to the first opening and the damping mesh can also be adjusted, which is more conducive to the adjustment of directivity and performance, with better performance and stronger adaptability. Third: This new type of MEMS single unit achieves directional characteristics, making it easier to save space in the whole device; Fourth: This new design is simple and the process is easy to implement.

[0017] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0018] Appendix Figure 1 This is a structural diagram of the background technology; Appendix Figure 2 This is a structural schematic diagram of Embodiment 1 of the present invention; Appendix Figure 3 This is another structural schematic diagram of Embodiment 1 of this utility model; Appendix Figure 4 This is another structural schematic diagram of Embodiment 1 of this utility model; Appendix Figure 5 This is a schematic diagram of the structure of Embodiment 2 of this utility model; Appendix Figure 6 This is another structural schematic diagram of Embodiment 2 of this utility model; Appendix Figure 7 This is another structural schematic diagram of Embodiment 2 of this utility model; Appendix Figure 8 This is a structural schematic diagram of Embodiment 3 of this utility model; Appendix Figure 9 This is another structural schematic diagram of Embodiment 3 of this utility model; Appendix Figure 10 This is another structural schematic diagram of Embodiment 3 of this utility model; Appendix Figure 11 This is another structural schematic diagram of Embodiment 3 of this utility model; Appendix Figure 12 This is another structural schematic diagram of the cavity described in this utility model; Appendix Figure 13 This is another structural schematic diagram of the cavity described in this utility model. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] In the description of this utility model, 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., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0021] In this utility model, unless otherwise explicitly specified and limited, the terms "installation", "setting", "connection", "fixing", "screw connection", etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0023] Example 1: As shown in the attached document Figure 2 - Appendix Figure 4As shown: A directional microphone includes a circuit board 1, on which a MEMS sensor 2, an ASIC chip 3, connecting gold wires 4, and a housing 5 are disposed. The connecting gold wires 4 electrically connect the MEMS sensor 2 and the circuit board 1. The circuit board 1 and the housing 5 form a first cavity 6. A first sound hole 7 is provided on the circuit board 1 below the MEMS sensor 2. A second sound hole 8 is provided on the circuit board 1 or on the housing 5. The second sound hole 8 may be located on the side wall of the housing 5 (as shown in the attached diagram). Figure 2 and attached Figure 3 ), or it can be located on the circuit board 1 (as shown in the attached) Figure 4 Of course, the second sound hole 8 can also be located on other walls of the housing 5; this embodiment also includes a second cavity 9, which corresponds to the second sound hole 8. The second cavity 9 is provided with a third sound hole 91. The second cavity 9, the third sound hole 91 and the second sound hole 8 form a first sound channel 92, which is maze-shaped.

[0024] The second cavity 9 is located inside the first cavity 6 (as shown in the attached diagram). Figure 3 (as shown), or located outside the first cavity 6 (as shown in the attached diagram). Figure 2 (as shown), or located in the body of the circuit board 1 (as shown in the attached diagram). Figure 4 As shown), at least one first baffle 93 is provided inside the second cavity 9 and between the second sound hole 8 and the third sound hole 91.

[0025] As attached Figure 2 and attached Figure 4 As shown, there are three or four first baffles 93. Of course, the number of first baffles 93 can be set according to actual requirements. The first baffles 93 and the inner wall of the second cavity 9 or two opposing first baffles 93 form a first channel 94. Adjacent first channels 94 are staggered. The first baffles 93 divide the second cavity 9 into small spaces and connect the divided small spaces through the first channels 94. They also form a first channel 92 with the third sound hole 91 and the second sound hole 8, thus forming a maze-shaped first channel 92. The other first baffles 93 below have the same function, so they will not be described again.

[0026] The first baffle 93 can also be as attached Figure 3 As shown, it includes two first baffles 93, each of which is provided with a second channel 95, and the second channels 95 between adjacent first baffles 93 are staggered.

[0027] Of course, the first baffle 93 can also be attached as shown. Figure 12 and attached Figure 13The device includes two first baffles 93, which are maze-shaped. A third channel 96 is formed between the two opposing first baffles 93. The third channels 96 are interconnected, with one end of the third channel 96 connected to the second sound hole 8 and the other end connected to the third sound hole 91, directly forming a maze-shaped first channel 92. Of course, the first baffles 93 can be spiral-shaped or other similar shapes to increase the sound path, which is more conducive to achieving an integrated design.

[0028] The aforementioned first baffle 93 is designed in a roundabout way to increase the sound path.

[0029] The first sound hole 7, the second sound hole 8, the third sound hole 91, and the first opening 95 can be a large sound hole or multiple small holes.

[0030] The first sound hole 7 and the second sound hole 8 serve as two sound holes for a directional microphone. The size and position of the sound holes are adjustable. A damping mesh can be provided on the outer side of the first sound hole 7 and the second sound hole 8 as needed. A damping mesh can also be provided on the outer side of the third sound hole 91 as needed. The third sound hole 91 leads to the first cavity 6 and acts above the MEMS sensor 2. The damping mesh is used to adjust the acoustic damping.

[0031] The first baffle 93 is a metal first baffle, an FR4 first baffle, an organic glass first baffle, a plastic first baffle, or an LCP first baffle.

[0032] The first baffle 93 can be integrally formed with the housing 5 or set independently and bonded together with glue or solder paste. The second cavity 9, the first baffle 93, and the circuit board 1 can be bonded together with glue or solder paste, and the inner wall of the second cavity 9 is bonded to the circuit board 1.

[0033] Example 2: As attached Figure 5 - Appendix Figure 6 As shown: The structure is the same as that in Embodiment 1, except that: in this embodiment, there is no second cavity 9, but a third cavity 10 is provided. The third cavity 10 corresponds to the first sound hole 7, and a fourth sound hole 101 is provided on the third cavity 10. The third cavity 10, the fourth sound hole 101, and the first sound hole 7 form a second sound channel 102, which is labyrinthine. The path length of the first sound channel 92 is L1, and the path length of the second sound channel 102 is L2, where L1>L2; or L1<L2.

[0034] The third cavity 10 is a labyrinthine cavity, located inside the first cavity 6 (as shown in the attached diagram). Figure 5); or located outside the first cavity 6 (as shown in the attached image). Figure 6 ); or located in the body of the circuit board 1 (as shown in the attached document). Figure 7 (There is no need to separately set the second baffle 103; the third cavity 10 can be directly set as a labyrinth-type cavity. Of course, it can be like the attached...) Figure 4 The second baffle is set up as described above.

[0035] At least one second baffle 103 is provided inside the third cavity 10 and between the first sound hole 7 and the fourth sound hole 101.

[0036] As attached Figure 5 As shown, it includes two second baffles 103. The number of second baffles 103 can be set according to actual requirements. A fourth channel 104 is formed between the second baffle 103 and the inner wall of the third cavity 10, or between two opposing second baffles 103. Adjacent fourth channels 104 are staggered. The second baffles 103 divide the third cavity 10 into small spaces, and connect these small spaces through the fourth channels 104. They also form a second channel 102 with the third sound hole 91 and the second sound hole 8, thus creating a maze-like second channel 102. The other second baffles 103 below have the same function and will not be described again.

[0037] The second baffle 103 can also be as attached. Figure 6 As shown, it includes two second baffles 103, each of which is provided with a fifth channel 105, and the fifth channels 105 between adjacent second baffles 103 are staggered.

[0038] Of course, the second baffle 103 can also be attached as shown. Figure 12 and attached Figure 13 The device includes two second baffles 103, which are maze-shaped. A sixth channel 106 is formed between the two opposing second baffles 103. The sixth channel 106 is interconnected with each other. One end of the sixth channel 106 is connected to the first sound hole 7 and the other end is connected to the fourth sound hole 101, directly forming a maze-shaped second sound channel 102. Of course, the second baffles 103 can be spiral-shaped or other similar shapes to increase the sound path, which is more conducive to realizing an integrated design.

[0039] Example 3: As shown in the attached document Figure 8 - Appendix Figure 11As shown: The structure is the same as that in Embodiment 1, except that: it includes a second cavity 9 and a third cavity 10. The second cavity 9 corresponds to the second sound hole 8, and the third cavity 10 corresponds to the first sound hole 7. At least one of the second cavity 9 and the third cavity 10 is a labyrinth-type cavity.

[0040] The second cavity 9 is located inside the first cavity 6, or outside the first cavity 6, or in the body of the circuit board 1.

[0041] The third cavity 10 is located inside the first cavity 6, or outside the first cavity 6, or in the body of the circuit board 1.

[0042] For example, see attached. Figure 8 As shown, the second cavity 9 is located inside the first cavity 6, and the third cavity 10 is located outside the first cavity 6. Both the second cavity 9 and the third cavity 10 are provided with corresponding first baffles 93 and second baffles 103; as shown in the attached diagram. Figure 9 As shown, the second cavity 9 does not contain the first baffle 93; as shown in the attached diagram. Figure 10 As shown, the third cavity 10 does not contain the second baffle 103, as indicated in the attached diagram. Figure 11 As shown, the second cavity 9 and the third cavity 10 are both labyrinth-type cavities.

[0043] Any combination of the shapes (maze-like cavities or empty cavities) and positions (inside the first cavity 6, outside the first cavity 6, or within the body of the circuit board 1) of the second cavity 9 and the third cavity 10 described above is within the scope of this embodiment and will not be described in detail here. Figure 8 - Appendix Figure 11 This is only a partial structural diagram.

[0044] In summary, through the different designs of the second cavity 9, the third cavity 10, the first baffle 93, and the second baffle 103, this new invention increases the sound path difference, realizes a pressure difference structure, and forms directivity.

[0045] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A directional microphone, comprising a circuit board, wherein a MEMS sensor, an ASIC chip, connecting gold wires, and a housing are disposed on the circuit board, the circuit board and the housing forming a first cavity, a first sound hole is disposed on the circuit board below the MEMS sensor, and a second sound hole is disposed on the circuit board or on the housing, characterized in that: It also includes a second cavity, which corresponds to the second sound hole. The second cavity is provided with a third sound hole. The second cavity, the third sound hole and the second sound hole form a first sound channel, which is maze-shaped.

2. A directional microphone according to claim 1, characterized in that: It also includes a third cavity, which corresponds to the first sound hole. The third cavity is provided with a fourth sound hole. The third cavity, the fourth sound hole and the first sound hole form a second sound channel. The sound path length of the first sound channel is L1 and the sound path length of the second sound channel is L2, where L1>L2 or L1<L2.

3. A directional microphone according to claim 2, characterized in that: The second channel is maze-shaped.

4. A directional microphone according to claim 1, characterized in that: The second cavity is a labyrinthine cavity. The second cavity is located inside the first cavity, or outside the first cavity, or in the body of the circuit board. At least one first baffle is provided inside the second cavity and between the second sound hole and the third sound hole.

5. A directional microphone according to claim 4, characterized in that: It includes a plurality of first baffles, and a first channel is formed between the first baffle and the inner wall of the second cavity or between two opposing first baffles, with adjacent first channels being staggered.

6. A directional microphone according to claim 4, characterized in that: It includes a plurality of first baffles, each of which is provided with a second channel, and the second channels between adjacent first baffles are staggered.

7. A directional microphone according to claim 4, characterized in that: It includes several first baffles, each baffle being in a labyrinthine shape. A third channel is formed between two opposing first baffles, and the third channels are interconnected. One end of each third channel is connected to the second sound hole, and the other end is connected to the third sound hole.

8. A directional microphone according to claim 3, characterized in that: The third cavity is a labyrinthine cavity, located inside the first cavity, outside the first cavity, or in the body of the circuit board; at least one second baffle is provided inside the third cavity and between the first sound hole and the fourth sound hole.

9. A directional microphone according to claim 8, characterized in that: It includes several second baffles, and a fourth channel is formed between the second baffles and the inner wall of the third cavity or between two opposing second baffles, with adjacent fourth channels being staggered.

10. A directional microphone according to claim 8, characterized in that: It includes a plurality of second baffles, each of which is provided with a fifth channel, and the fifth channels between adjacent second baffles are staggered.

11. A directional microphone according to claim 8, characterized in that: It includes several second baffles, the second baffles are in a maze shape, and a sixth channel is formed between two opposing second baffles. The sixth channel is interconnected with each other, one end of the sixth channel is connected to the first sound hole and the other end is connected to the fourth sound hole.

Images