WO2023203654A1

WO2023203654A1 - Microphone

Info

Publication number: WO2023203654A1
Application number: PCT/JP2022/018228
Authority: WO
Inventors: 成高鈴木; 和洋小川
Original assignee: 国立大学法人東北大学
Priority date: 2022-04-19
Filing date: 2022-04-19
Publication date: 2023-10-26
Also published as: WO2023203996A1

Abstract

A microphone 100 comprises: an oscillator 10; a magnet 20 that directly or indirectly contacts the oscillator and that can oscillate by sound waves; and a magnetic sensor 30 that is provided at a position spaced apart from the outside of the microphone 100, that detects magnetic-force fluctuations due to the oscillation of the magnet, and that outputs such magnetic-force fluctuations as electrical signals.

Description

microphone

The present invention relates to a microphone.

Conventionally, acoustic components such as speakers and microphones have been known to have a waterproof and pressure-resistant structure. For example, by making the space inside the casing airtight using a flexible sheet to make it waterproof, and by equalizing the pressure applied to the front and back sides of the diaphragm, there is no possibility that the diaphragm will be deformed or damaged. A technique for suppressing this is known (Patent Document 1).

Furthermore, in acoustic devices, it is known that the gas in the internal space expands and contracts under the influence of changes in the external environment, which affects the vibration characteristics. To prevent this, for example, by using the internal air of the device as a damper, the outflow of air is restricted, and by providing ventilation holes on the side of the housing, when the diaphragm vibrates, the air in the internal space is removed through the ventilation holes. A technique is known in which the liquid is discharged from the device to the outside of the device (Patent Document 2).

Japanese Patent Application Publication No. 2003-18685 International Publication No. 2004/023843

However, it is difficult to achieve both waterproof and pressure-resistant performance and suppression of gas expansion in the internal space with a single microphone. The present invention was devised in view of the above-mentioned problems, and an object of the present invention is to provide a compact microphone structure that has waterproof and pressure-resistant performance without impairing its acoustic performance even when the surrounding environment changes.

The present invention has been made to solve at least part of the above problems, and can be realized in the following aspects or application examples.
(1) The microphone according to this application example includes a vibrating body, a magnet that is in direct or indirect contact with the vibrating body and can be vibrated by sound waves, and a magnet that is provided at a position separated from the outside of the microphone. and a magnetic sensor that detects magnetic force fluctuations due to vibrations and outputs the magnetic force fluctuations as an electrical signal.

(2) The vibrating body is made of a soft material, the magnet is laminated on the upper surface, and the magnetic sensor is separated from the outside of the microphone by laminating the soft material on the magnetic sensor. It is preferable.

(3) Preferably, the microphone according to this application example further includes a diaphragm laminated on the magnet.

(4) The soft material preferably encapsulates a liquid.

(5) The microphone according to this application example preferably further includes a case that has a height greater than the height of the soft material in the loading direction of the soft material and the magnet, and that encloses the soft material.

(6) The vibrating body is made of a soft material, and the microphone further includes a case in which the soft material is laminated on an upper surface and the magnetic sensor is enclosed therein to separate the microphone from the outside, and the magnetic sensor includes: The case may include an NVC diamond sensor, a green LED light emitting unit that inputs light to the NVC diamond sensor, and a light receiving unit that is connected to a side facing the upper surface of the case and can detect light emission from the NVC diamond sensor. preferable.

(7) The vibrating body is made of a soft material, and the microphone further includes a case in which the soft material is laminated on a side surface and the magnetic sensor is enclosed in the case to separate the microphone from the outside, and the magnetic sensor includes: The case may include an NVC diamond sensor, a green LED light emitting section connected to a side perpendicular to the side surface of the case, and a green LED light emitting section inputting light to the NVC diamond sensor, and a light receiving section capable of detecting light emission from the NVC diamond sensor. preferable.

(8) The microphone according to this application example further includes a first case and a second case, and the vibrating body is arranged inside the first case and the second case. The magnetic sensor is a diaphragm sandwiched between the first case and the second case, and the magnetic sensor is attached to either the first case or the second case, and is subjected to waterproof and pressure-resistant treatment. Therefore, it is preferable that the microphone be separated from the outside of the microphone.

(9) The side of the diaphragm that faces the first case communicates with the outside of the first case via a hole provided in the first case, and the side of the diaphragm that faces the second case communicates with the outside of the first case through a hole provided in the first case. Preferably, the side facing the case communicates with the outside of the second case via a hole provided in the second case.

(10) The microphone according to this application example preferably includes a base plate and a microphone unit disposed on the base plate, and the microphone unit preferably has the configuration described in (1).

According to the present invention, it is possible to provide a compact microphone structure that has waterproof and pressure-resistant performance without deteriorating its acoustic performance even when the surrounding environment changes.

FIG. 1 is a vertical cross-sectional perspective view showing the configuration of a microphone according to a first embodiment. FIG. 7 is a vertical cross-sectional perspective view showing the configuration of a microphone according to a first modification of the first embodiment. FIG. 7 is a vertical cross-sectional perspective view showing the configuration of a second modified example microphone of the first embodiment. FIG. 7 is a vertical cross-sectional perspective view showing the configuration of a microphone according to a second embodiment. FIG. 7 is a vertical cross-sectional perspective view showing the configuration of a microphone according to a modification of the second embodiment. FIG. 7 is a vertical cross-sectional perspective view showing the configuration of a microphone according to a third embodiment. FIG. 7 is a vertical cross-sectional perspective view showing the configuration of a microphone according to a modified example of the third embodiment. FIG. 7 is a left perspective view showing the configuration of a microphone according to a fourth embodiment. It is a right perspective view which shows the structure of the microphone of 4th Embodiment. FIG. 9 is a sectional view taken along the line AA in FIG. 9 and a partially enlarged view thereof. FIG. 9 is a sectional view taken along the line BB in FIG. 9; FIG. 7 is a right perspective view of a modification of the fourth embodiment. 13 is a sectional view taken along the line CC in FIG. 12. FIG.

A microphone as an embodiment will be described with reference to the drawings. The embodiments shown below are merely illustrative, and there is no intention to exclude the application of various modifications and techniques not specified in the embodiments below. The configuration of this embodiment can be modified and implemented in various ways without departing from the spirit thereof. Further, they can be selected or combined as necessary.

The microphone according to this embodiment is an electronic device that converts audio (sound waves) into electrical signals. The microphone according to the present embodiment can be used in various devices having a voice recognition function, such as small wireless terminals such as smartphones, information processing devices (computers), various objects equipped with computers, such as electronic devices, machines such as vehicles, etc. , applicable to devices including guns, etc.

[A. composition]

[1. First embodiment]
A first embodiment will be described with reference to FIG. FIG. 1 is a vertical cross-sectional perspective view showing the configuration of a microphone 100 according to the first embodiment. Microphone 100 includes a vibrating body 10, a magnet 20, and a magnetic sensor 30.

The vibrating body 10 holds the magnet 20 so that it can vibrate. An example of the vibrating body 10 is a soft material 11, such as gel or rubber. Moreover, the vibrating body 10 of this embodiment has the magnet 20 laminated on the top surface. The vibrating body 10 vibrates in the same direction as the vibration direction of the magnet 20 in conjunction with the vibration of the magnet 20. In this embodiment, the shape of the vibrating body 10 is a cylinder.

The magnet 20 is in direct or indirect contact with the vibrating body 10 and can be vibrated by sound waves. A portion of the magnet 20 may be in contact with the external space (outside air) so as to be able to receive sound waves, and the other portion may be in contact with the vibrating body 10. The magnet 20 receives sound waves at the portion that contacts the external space, and vibrates in a direction substantially perpendicular to the direction in which the portion that contacts the external space extends. The magnet 20 of this embodiment has a disk shape, and its lower surface is in direct or indirect contact with the vibrating body 10, and its upper surface is in contact with the external space, so it vibrates up and down depending on the size of the sound wave. . The magnet is, for example, a neodymium magnet.

If the magnet 20 and the vibrating body 10 are, for example, insert molded, they come into direct contact. Alternatively, by coating (fixing) the powdered magnet 20 on a part or the entire surface of the vibrating body 10 that contacts the external space using an adhesive or the like, the magnets 20 come into indirect contact with each other. In this embodiment, the powdered magnet 20 may be fixed to the vibrating body 10 in a disk shape. By using the powdered magnet 20, the inertial force of the magnet 20 can be reduced.

The magnetic sensor 30 is provided at a location away from the outside of the microphone 100, detects magnetic force fluctuations due to vibrations of the magnet 20, and outputs the magnetic force fluctuations as an electrical signal. The magnetic sensor 30 is, for example, a Hall IC or an NVC diamond sensor. The magnetic sensor 30 is separated from the outside of the microphone 100 by laminating the soft material 11 on the magnetic sensor 30 . In this embodiment, the magnetic sensor 30 is included in the lower part of the soft material 11. As a result, the magnetic sensor 30 has waterproof and pressure-resistant performance, and even if the microphone 100 is submerged in water, the intrusion of liquid and the input of pressure into the microphone are blocked, and the performance of the magnetic sensor 30, that is, the fluctuation of magnetic force due to sound waves, is prevented. The performance of receiving and outputting electrical signals is not degraded. In this embodiment, the pressure resistance is assumed to be about 10 atm, but the present invention can be implemented at a pressure resistance depending on the application of the device in which the microphone 100 is installed.

The magnet 20 faces the magnetic sensor 30 with the vibrating body 10 in between. The magnet 20 is arranged in a direction in which the magnetic sensor 30 can detect variations in magnetic force. In other words, the magnetic sensor 30 is preferably arranged in the direction in which the magnet 20 vibrates (the direction of magnetic flux). In this embodiment, since the magnet 20 vibrates up and down, the magnetic sensor 30 is arranged on the opposite side of the surface where the magnet 20 contacts the external space, and detects the vibration of the magnet 20 directly or through the vibration of the vibrating body 10. Receive.

Only the soft material 11 exists between the magnet 20 and the magnetic sensor 30, that is, there is no gas layer between the magnet 20 and the magnetic sensor 30. Therefore, the magnet 20 is not affected by vibration characteristics caused by expansion and contraction of the gas in the internal space of the microphone 100 due to changes in the environment in the external space. As a result, no pressure is applied to the vibration direction of the magnet 20 and the vibrating body 10, so that the displacement of the magnet 20 due to internal pressure can be prevented, and the vibration of the magnet 20 and the vibrating body 10 is not restricted. Interference with the detection of magnetic force fluctuations by the sensor 30 can be suppressed. Therefore, high quality acoustic performance can be obtained.

The basic structure consisting of the vibrating body 10, magnet 20, and magnetic sensor 30 that constitutes the microphone 100 may be referred to as a microphone unit. The microphone unit is arranged on the upper surface of the base plate 50. The base plate 50 is a rigid member for supporting the microphone unit.

The magnetic sensor 30 is electrically connected to an electronic device board (not shown) at the bottom of the base plate 50 by soldering or the like (electrical connection 40). Electrical connections 40 are contained within base plate 50 . As a result, the electrical connection 40 is separated from the outside of the microphone 100, so that it has waterproof and pressure-resistant performance.

[1-1. First modification of the first embodiment]
Next, a first modification of the first embodiment will be described. FIG. 2 is a vertical cross-sectional perspective view showing the configuration of a microphone 100 according to a first modification of the first embodiment. The first modification differs from the microphone 100 of the first embodiment in that it includes a diaphragm 12. The differences will be mainly explained below. In addition, in the description of the first modification, the same reference numerals as those used in the first embodiment are the same or substantially similar.

In the microphone 100 of the first modification of the first embodiment, a diaphragm 12 is further laminated on the magnet 20. In the example shown in FIG. 2, the diaphragm 12 is arranged so as to be in contact with the upper side of the magnet 20, that is, the part of the magnet 20 that contacts the external space, and receives sound waves. Alternatively, the diaphragm 12 may be placed below the magnet 20, that is, between the magnet 20 and the vibrating body 10. The diaphragm 12 is preferably a flat plate that is larger than the magnet 20 in order to easily receive the sound waves. Thereby, sound waves can be collected with higher sensitivity than the magnet 20 alone. Furthermore, since the diaphragm 12 comes into contact with the external space, it is preferably made of a material that is not only rigid enough to receive sound waves with good sensitivity, but also able to withstand pressure from the outside. The diaphragm 12 is made of lightweight metal such as aluminum or magnesium, or resin.

[1-2. Second modification of the first embodiment]
Next, a second modification of the first embodiment will be described. FIG. 3 is a vertical cross-sectional perspective view showing the configuration of a microphone 100 according to a second modification of the first embodiment. The second modification differs from the microphone 100 of the first embodiment in that the soft material 11 encloses a liquid. The differences will be mainly explained below. In addition, in the description of the second modification, the same reference numerals as those used in the first embodiment are the same or substantially similar.

As shown in FIG. 3, in the microphone 100 of the second modification of the first embodiment, the soft material 11 further encloses the liquid 13. The soft material 11 has a space of an appropriate shape and size therein, and a liquid 13 is sealed therein. The liquid 13 is used to adjust the vibration sensitivity of the soft material 11. The liquid 13 is sealed with a soft material 11 so as not to come into contact with the magnetic sensor 30. The liquid 13 is, for example, water/alcohol, and preferably has a viscosity of 0.5 to 50 mPa·s. The liquid 13 is appropriately selected depending on the type of the soft material 11 with which it comes into contact. The amount of liquid 13 is determined as appropriate depending on the vibration sensitivity. Note that the magnet 20 shown in FIG. 3 may further include a diaphragm 12.

[2. Second embodiment]
A second embodiment will be described with reference to FIG. 4. FIG. 4 is a vertical cross-sectional perspective view showing the configuration of the microphone 100 according to the second embodiment. The second embodiment is different from the microphone 100 of the first embodiment (including modified examples) in that it includes a case 60 that encloses a soft material 11. The differences will be mainly explained below. In the description of the second embodiment, the same reference numerals as those used in the first embodiment (including modified examples) are the same or substantially similar.

As shown in FIG. 4, the microphone 100 of the second embodiment further includes a case 60 that encloses the soft material 11. The case 60 protects the entire microphone unit, guides the vibration of the magnet 20 in a specific direction, and stabilizes the vibration direction. The case 60 is a rigid body, such as plastic or metal. In this embodiment, the case 60 has a cylindrical shape, encloses the soft material 11, and the side surface of the soft material 11 is in contact with the inner surface of the case 60. Case 60 has a height greater than or equal to the height of soft material 11 in the loading direction of soft material 11 and magnet 20 . In this embodiment, the soft material 11 and the case 60 are at the same height. Although FIG. 4 shows an example including the diaphragm 12 and the liquid 13, the diaphragm 12 and the liquid 13 may not be provided.

[2-1. Modification of second embodiment]
FIG. 5 is a vertical cross-sectional perspective view showing the configuration of a microphone 100 according to a modification of the second embodiment. This modification differs from the microphone 100 of the second embodiment in the height of the case.

As shown in FIG. 5, the case 60r of the modified microphone 100 has a height greater than the height of the soft material 11 in the loading direction of the soft material 11 and the magnet 20. The case 60r encloses the vibrating body 10 and increases the amplitude of the sound wave inside a portion extending above the magnet 20. Therefore, the case 60r of this modification may be referred to as a case 60r with a resonance tube. The shape of the resonance tube-equipped case 60r of this modification is a cylindrical shape in which the side surface containing the soft material 11 extends upward.

[3. Third embodiment]
A third embodiment will be described with reference to FIG. FIG. 6 is a vertical cross-sectional perspective view showing the configuration of the microphone 100 according to the third embodiment. The third embodiment is characterized in that, in contrast to the microphone 100 of the first embodiment (including modified examples), an NVC diamond sensor is particularly used as the magnetic sensor. Below, the description will focus on the feature points. In the description of the third embodiment, the same reference numerals as those used in the first embodiment (including modified examples) are the same or substantially similar.

As shown in FIG. 6, the microphone 100 of the third embodiment includes a case 60 in addition to a soft material 11 and a magnet 20 that is in contact with the soft material 11 and can vibrate by sound waves. The magnetic sensor 30 of this embodiment includes an NVC diamond sensor 31, a green LED light emitting section 32, and a light receiving section 33. The basic structure consisting of these three

parts

31, 32, 33 may be called an NVC diamond sensor unit.

The case 60 has the soft material 11 laminated on its upper surface and encloses the magnetic sensor 30, thereby separating it from the outside of the microphone 100. This allows the magnetic sensor 30 to maintain waterproof and pressure-resistant performance. Case 60 is a rigid body. A magnet 20 is laminated on the upper surface of the soft material 11. Magnet 20 faces NVC diamond sensor 31 with soft material 11 in between. The NVC diamond sensor 31 of this embodiment is installed upright in the same direction as the direction in which the magnet 20 vibrates. In this embodiment, the proportion of the soft material 11 in the entire microphone 100 is small. The size of the soft material 11 is selected depending on the required sensitivity of the NVC diamond sensor 31.

The NVC diamond sensor unit, which is the magnetic sensor 30, is connected to the side of the case 60 that faces the upper surface on which the soft material 11 is laminated. The NVC diamond unit also includes an NVC diamond sensor 31 , a green LED light emitting section 32 that inputs light to the NVC diamond sensor 31 , and a light receiving section 33 that can detect light emission from the NVC diamond sensor 31 . The NVC diamond sensor 31 is arranged between the green LED light emitting section 32 and the light receiving section 33.

Here, the NVC diamond sensor 31 will be explained. NVC of the NVC diamond sensor 31 is an abbreviation for Nitrogen Vacancy Center. NVC is a defect in which carbon (C) adjacent to the structure in the diamond crystal lattice is replaced with nitrogen (N) and vacancy (V), respectively. NVC exhibits a magnetic property called spin when it captures electrons and becomes negatively charged. Diamond has a wide band gap due to its strong bonds, and has the property of not releasing captured electrons even when high energy of several hundred degrees Celsius or more is applied to it. This helps stabilize the spin, and normally cooling is required to maintain the quantum state, but NVC can maintain the quantum state even at room temperature.

In NVC, captured electrons easily react to slight variations in the electrical, magnetic, and optical properties of their surroundings. In addition to its atomic-like functionality, NVC has photoluminescent properties that absorb and emit colored photons. Irradiation with light or microwaves changes the state of the center, and the spin of the electrons changes accordingly. NVC emits different amounts of red light depending on the state of its electrons. Such light contains quantum information about magnetic and electric fields, and can be used in a variety of sensing applications that handle minute information, such as biosensing, neural imaging, object detection, and position sensing (GPS).

The operation of the NVC diamond sensor unit will be explained. The NVC diamond sensor 31 of this embodiment has an I-shape, diamond particles are arranged in recesses on both sides, and magnetism is detected in the entire recess. The number of diamond particles is adjusted depending on the required sensitivity. The green LED light emitting part 32 and the light receiving part 33 each have a convex part formed on the side surface facing the NVC diamond sensor 31, which can fit into a concave part of the NVC diamond sensor 31. By forming the three

parts

31, 32, and 33 into such a shape, it is possible to achieve good detection and to realize a compact microphone 100. When the green light emitted from the green LED light emitting unit 32 passes through the NVC diamond sensor, it changes to red due to the change in the magnetic strength of the magnet 20 detected by the recessed part of the NVC diamond sensor 31. The brightness of the red light changes according to changes in the magnetic strength of the magnet 20. The intensity of the light output from the NVC diamond sensor 31 is detected by a light receiving section (photodiode) 33.

The NVC diamond sensor 31, the green LED light emitting section 32, and the light receiving section 33 are each electrically connected to an electronic device board (not shown) at the bottom of the base plate 50 (electrical connection 40).

The space in which the magnet 20 and the NVC diamond sensor 31 are arranged is separated by the case 60, that is, there is no gas layer between the magnet 20 and the case 60. Therefore, the magnet 20 is not affected by vibration characteristics caused by expansion and contraction of the gas in the internal space of the microphone 100 due to changes in the environment in the external space. As a result, no pressure is applied to the vibration direction of the magnet 20 and the vibrating body 10, so that displacement of the magnet 20 due to internal pressure can be prevented, and the vibration of the magnet 20 and the soft material 11 is not restricted. Interference with the detection of magnetic force fluctuations by the sensor 31 can be suppressed. Therefore, high quality acoustic performance can be obtained.

[3-1. Modification of third embodiment]
FIG. 7 is a vertical cross-sectional perspective view showing the configuration of a microphone 100 according to a modification of the third embodiment. In FIG. 7, this modification differs from the microphone 100 of the third embodiment in the position of the soft material 11 laminated on the case 60.

As shown in FIG. 7, in the modified microphone 100, the case 60 has the soft material 11 laminated on the side surface and contains the magnetic sensor 30, thereby separating it from the outside of the microphone 100. This allows the magnetic sensor 30 to maintain waterproof and pressure-resistant performance. Case 60 is a rigid body. A magnet 20 is laminated on the upper surface of the soft material 11. The magnet 20 faces the side surface of the NVC diamond sensor 31 with the soft material 11 in between. The NVC diamond sensor 31 of this embodiment is installed vertically to the direction in which the magnet 20 vibrates.

The NVC diamond sensor unit, which is the magnetic sensor 30, is connected to the side of the case 60 that is perpendicular to the side surface on which the soft material 11 is laminated. As mentioned above, the NVC diamond sensor 31 can detect slight fluctuations in the surrounding electrical, magnetic, and optical characteristics, so it can detect vibrations of the magnet 20 even if it is in a position perpendicular to the magnet 20. can be detected.

[4. Fourth embodiment]
The fourth embodiment will be described with reference to FIGS. 8 to 11. The fourth embodiment is different from the microphones of the first to third embodiments (including modified examples) in that the structure of the case and the positions of the magnet and the magnetic sensor are different. Below, the description will focus on the feature points. In the description of the fourth embodiment, the same reference numerals as those used in the first to third embodiments (including modifications) are the same or substantially similar.

FIG. 8 is a left perspective view showing the configuration of the microphone 100 of the fourth embodiment. Further, FIG. 9 is a right perspective view showing the configuration of the microphone 100 of the fourth embodiment. As shown in FIGS. 8 and 9, the microphone 100 further includes a first case 61 and a second case 62. The first case 61 and the second case 62 are provided with holes that communicate with the external space. In this embodiment, the first case 61 and the second case 62 have the same shape, and the first case 61 is provided with three small circular holes, and the second case 62 is provided with three small circular holes. And one circular hole larger than the small circles is provided in the middle of these small circles. The positions of the small circular holes in the

cases

61 and 62 coincide with each other.

The first case 61 and the second case 62 each have a recess of the same size formed on one side, and the positions of the recesses match (see FIG. 10). The case of the microphone 100 is formed by making the concave portions face each other and tightly fitting the outer circumferences of the surfaces of the first case 61 and the second case 62 on which the concave portions are provided over the entire circumference. The microphone unit is arranged on the upper surface of the base plate 50. The lower portions of the first case 61 and the second case 62 are surrounded by a waterproof seal member 63. The seal member 63 will be described later.

The magnetic sensor 30 is attached to either the first case 61 or the second case 62, and is separated from the outside of the microphone 100 by being subjected to waterproof and pressure-resistant treatment 64. The magnetic sensor 30 may be placed in the direction in which the magnet 20 vibrates (the magnetic flux direction), and the position where the magnetic sensor 30 is attached may be outside or inside the

cases

61 and 62. In this embodiment, the magnetic sensor 30 is attached to the outside of the first case 61. When the magnetic sensor 30 is installed inside the

cases

61 and 62, it may be installed on the side with the vibrating membrane 14 in between, where there is a part that receives the sound waves of the magnet 20, or it can be installed on the side where the part does not exist. (See FIG. 10).

Furthermore, in this embodiment, an example is shown in which the sensor part and the amplifier part of the magnetic sensor 30 are molded with resin and have a waterproof structure, and the waterproof pressure-resistant treatment 64 is applied to the electrical connection 40 and the electrical connection of the magnetic sensor 30. It is applied to the parts related to the connection 40. If the sensor section and the amplifier section of the magnetic sensor 30 do not have a waterproof structure, the entire magnetic sensor 30 may be provided with this. For the waterproof and pressure-resistant treatment 64, there is a method of sealing and waterproofing, for example, by insert molding an elastic material such as resin, rubber, or elastomer. In particular, it is preferable that the waterproof and pressure-resistant treatment 64 be performed to the extent that the same level of strength as the

cases

61 and 62 can be obtained. Instead of the waterproof and pressure-resistant treatment 64, the magnetic sensor 30 may be covered with a rigid body.

FIG. 10 is a sectional view taken along the line AA in FIG. 9 and a partially enlarged view thereof. As shown in FIG. 10, a vibrating body 10 that directly or indirectly contacts a magnet 20 that receives sound waves taken in through the holes is arranged in the internal spaces of the

cases

61 and 62. An example of the vibrating body 10 is a vibrating plate 12, which is laminated under the magnet 20 in the example of FIG. The diaphragm 12 is connected to

cases

61 and 62 via a diaphragm 14. In other words, the vibrating body 10 of this embodiment is the diaphragm 12 sandwiched between the first case 61 and the second case 62, inside the first case 61 and the second case 62. Further, the side of the diaphragm 12 facing the first case 61 communicates with the outside of the first case through a hole provided in the first case 61, and the side facing the second case 62 of the diaphragm 12 communicates with the outside of the first case through a hole provided in the first case 61. The opposing side communicates with the outside of the second case 62 via a hole provided in the second case.

The vibrating membrane 14 freely deforms and receives sound waves. Since the ends of the vibrating membrane 14 are held between the

cases

61 and 62, the internal spaces of the

cases

61 and 62 are divided into two spaces by the vibrating membrane 14. Since the vibrating membrane 14 is connected to the external space through the hole, it is preferably made of a material that can withstand external pressure, such as PVC film. Since the vibrating membrane 14 is arranged parallel to the

cases

61 and 62, the magnet 20 receives the sound waves input through the holes and vibrates in a direction substantially perpendicular to the direction in which the

cases

61 and 62 are installed.

As shown in the enlarged view of FIG. 10, the boundary surface of the internal space formed by the first case 61 and the second case 62 is a smooth curved surface. In this embodiment, the internal space has a disk shape, and its cross section and longitudinal section are elliptical. When large pressure is applied from the external space, the entire vibrating membrane 14 moves in the direction of the pressure and in the opposite direction due to reaction, and the vibrating membrane 14 may come into contact with the inner wall, but if the inner wall has a curved surface. By providing this, local damage to the vibrating membrane 14 can be prevented. This damage prevention structure may be referred to as a backup structure 65.

In this embodiment, the magnet 20 and the magnetic sensor 30 are separated by the case 61, and since the case 61 is provided with a hole, a gas layer exists. However, even if the gas in the internal space of the

cases

61, 62 is affected by a change in the environment of the external space, the holes provided in the

cases

61, 62 cause the internal space of the

cases

61, 62 to be reduced to the external space. The expanded gas in the inner space flows out to the outer space through the hole. Furthermore, even if pressure is applied to the vibration direction of the magnet 20 and the vibrating body 10, the backup structure 65 supports the entire vibrating membrane 14, so that the vibrating membrane 14 will not be damaged. The influence on the connected diaphragm 12 and magnet 20 can be reduced. Thereby, damage to the diaphragm 14 and the diaphragm 12 can be prevented, and even if high external pressure is temporarily applied to one side, the diaphragm 14 and the diaphragm 12 can be restored without damage, and high-quality acoustic performance can be obtained.

FIG. 11 is a sectional view taken along the line BB in FIG. 9. As shown in FIG. 11, the magnetic sensor 30 placed outside the first case 61 detects magnetic force fluctuations of the magnet 20 in the internal space. The electrical connection 40 of the magnetic sensor 30 extends from inside the main body of the magnetic sensor 30 to the bottom of the first case 61 and is connected to an electronics board (not shown) at the bottom of the base plate 50.

The magnet 20, the diaphragm 12, and the diaphragm 14 can receive sound waves even when water flows in through the holes and comes into contact with water, and the performance after water removal does not deteriorate.

[4-1. Modification of fourth embodiment]
A modification of the fourth embodiment will be described with reference to FIGS. 12 and 13. This modification is different from the microphone of the fourth embodiment in that the microphone is shown together with a housing in which the microphone is incorporated. The differences will be mainly explained below. In addition, in this modification, the same reference numerals as those used in the description of the first to fourth embodiments (including the modification) are the same or substantially similar.

FIG. 12 is a right perspective view of a modification of the fourth embodiment. As shown in FIG. 12, the microphone 100 is connected to a casing (attachment destination casing) 70 to be incorporated. Although the object into which the microphone 100 is installed is not limited to a specific device, this embodiment will be described using an electronic device as an example.

FIG. 13 is a sectional view taken along the line CC in FIG. 12. The sealing member 63 of the microphone 100 is in contact with the casing 70 to which it is attached. That is, the microphone 100 is fitted into the attachment destination housing 70 at the seal member 63. As a result, even if the portion above the seal member 63 of the microphone 100 comes into contact with water, the seal member 63 prevents water from entering the space where the electrical connection 40 of the magnetic sensor 30 is arranged. Damage to the connection 40 can be prevented. Although the electrical connection 40 of this embodiment is not subjected to waterproof and pressure-resistant treatment 64, it may be subjected to waterproof and pressure-resistant treatment 64 in order to further improve safety.

[B. effect]
(1) The microphone 100 includes a vibrating body 10, a magnet 20 that is in direct or indirect contact with the vibrating body and is capable of vibrating by sound waves, and is provided at a position separated from the outside of the microphone 100, and is provided with a magnet 20 that is in direct or indirect contact with the vibrating body and can vibrate by sound waves. It includes a magnetic sensor 30 that detects magnetic force fluctuations and outputs the magnetic force fluctuations as electrical signals. The structure in which the magnet 20 vibrates with sound waves and the magnetic sensor 30 detects magnetic force fluctuations due to the vibration of the magnet 20 is new. Moreover, since the magnetic sensor 30 has waterproof and pressure-resistant performance, even if the microphone 100 is submerged in water, the time required for recovery can be shortened.

(2) The vibrating body 10 is made of a soft material 11, and the magnet 20 is laminated on the upper surface, and the magnetic sensor 30 is separated from the outside of the microphone 100 by laminating the soft material 11 on the magnetic sensor 30. Ru. The soft material 11 allows magnetic force fluctuations caused by the vibrations of the magnet 20 to be reliably transmitted to the magnetic sensor 30, and the soft material 11 makes the magnetic sensor 30 waterproof and pressure resistant, allowing the microphone to be used safely even in environments with water. be able to. Further, since the microphone 100 has a small number of parts, it can be configured compactly. Since there is no gas layer between the magnet 20 and the magnetic sensor 30, the magnet 20, the vibrating body 10, and the magnetic sensor 30 are not adversely affected by the expansion and contraction of the gas in the internal space.

(3) The microphone 100 further includes a diaphragm 12 laminated on the magnet 20. Thereby, sound waves can be detected with higher sensitivity.

(4) The soft material 11 encloses the liquid 13. Thereby, the sensitivity of the vibrating body 10 can be adjusted.

(5) The microphone 100 further includes a case 60r that has a height larger than the height of the soft material 11 in the loading direction of the soft material 11 and the magnet 20, and encloses the soft material 11. As a result, the amplitude of the sound waves can be increased inside the portion extending above the magnet 20, so that weakly vibrating sound waves can be reliably detected.

(6) The vibrating body 10 is a soft material 11, and the microphone 100 further includes a case 60 in which the soft material 11 is laminated on the upper surface, and a case 60 is separated from the outside of the microphone 100 by enclosing a magnetic sensor 30. 30 is connected to the side facing the upper surface of the case 60, and includes an NVC diamond sensor 31, a green LED light emitting section 32 that inputs light to the NVC diamond sensor 31, and a light receiving section 33 that can detect light emission from the NVC diamond sensor 31. including. By using the NVC diamond sensor 31, it is possible to reliably detect weak magnetic force fluctuations of the magnet 20.

(7) The vibrating body 10 is a soft material 11, and the microphone 100 further includes a case in which the soft material is laminated on the side surface and the magnetic sensor is enclosed in the case to separate the microphone 100 from the outside, is connected to a side perpendicular to the side surface of the case, and includes an NVC diamond sensor, a green LED light emitting section that inputs light to the NVC diamond sensor, and a light receiving section capable of detecting light emission from the NVC diamond sensor. . As a result, by using the NVC diamond sensor 31, even when the NVC diamond sensor 31 is arranged in a direction perpendicular to the vibration direction of the magnet 20, it is possible to reliably detect weak magnetic force fluctuations of the magnet 20. I can do it.

(8) The microphone 100 further includes a first case 61 and a second case 62, and the vibrating body 10 is arranged inside the first case 61 and the second case 62. The diaphragm 12 is sandwiched between a diaphragm 61 and a second case 62, and the magnetic sensor 30 is attached to either the first case 61 or the second case and is subjected to waterproof and pressure-resistant treatment 64. The microphone 100 is separated from the outside. The diaphragm 12 is protected by the

cases

61 and 62 to prevent damage, and the magnetic sensor 30 is subjected to waterproof and pressure-resistant treatment 64, so the microphone can be used safely even in environments with water.

(9) The side of the diaphragm 12 facing the first case 61 communicates with the outside of the first case 61 through the hole provided in the first case 61, and The side facing 62 communicates with the outside of second case 62 through a hole provided in second case 62 . Thereby, even if the gas inside the

cases

61 and 62 expands and contracts due to changes in the environment of the external space, the influence of the internal pressure on the diaphragm 12 can be reduced.

(10) The microphone includes a base plate 1 and a microphone unit disposed on the base plate, and the microphone unit has the configuration described in (1) above. This allows the microphone unit to be stably installed in any location.

[C. others]
The configuration of the microphone 100 described above is an example, and is not limited to the configuration described above. For example, the following modifications and changes can be made.

The components of the microphone 100 can take various shapes. In the figure, the shape of the magnet 20 is shown as a disk, and in the figure, the vibrating body 10 is shown as a cylinder or a prism, but the shape is not limited to these shapes. Similarly, the case 60 has various shapes such as a cylinder, a square, and an ellipse, but is not limited to these shapes. Further, although an example has been shown in which the vibrating body 10 and the magnet 20 have the same shape, they may have different shapes. The shape of the resonance tube-equipped case 60r may be a shape that widens upward or a shape that narrows toward the top. The shapes of the

parts

31, 32, and 33 of the NVC diamond sensor unit are also not limited to the above. The shapes of the first case 61 and the second case 62 and the size and number of holes provided therein can be arbitrarily selected.

The magnetic sensor 30 is not limited to Hall IC and NVC diamond sensors, and other sensors capable of detecting changes in magnetic force may be used.

The mounting position of the magnetic sensor 30 is not limited to the above example as long as the magnetic force fluctuation of the magnet 20 can be received. For example, in the first and second embodiments, any position inside the vibrating body 10, in the third embodiment, any position inside the case 60, and in the fourth embodiment, at any position inside the first case 61 or the second case 62. May be attached.

100 Microphone 10 Vibrating body 11 Soft material 12 Diaphragm 13 Liquid 14 Vibrating membrane 20 Magnet 30 Magnetic sensor 31 NVC diamond sensor 32 Green LED light emitting section 33 Light receiving section 40 Electrical connection 50 Base plate 60 Case 60r Case with resonance tube (case)
61 First case 62 Second case 63 Seal member 64 Waterproof and pressure resistant treatment 65 Backup structure 70 Mounting casing

Claims

a vibrating body;
a magnet that is in direct or indirect contact with the vibrating body and is capable of vibrating by sound waves;
a magnetic sensor that is provided at a location away from the outside of the microphone, detects magnetic force fluctuations due to vibrations of the magnet, and outputs the magnetic force fluctuations as an electrical signal;
equipped with a microphone.
The vibrating body is made of a soft material, and the magnet is laminated on the upper surface,
The magnetic sensor is separated from the outside of the microphone by laminating the soft material on the magnetic sensor.
The microphone according to claim 1.
further comprising a diaphragm laminated on the magnet;
The microphone according to claim 1 or 2.
the soft material encloses a liquid;
The microphone according to claim 2.
further comprising a case that has a height greater than the height of the soft material in the loading direction of the soft material and the magnet, and that encloses the soft material;
The microphone according to claim 2 or 4.
The vibrating body is made of a soft material,
further comprising a case in which the soft material is laminated on an upper surface and the magnetic sensor is enclosed therein to separate the microphone from the outside;
The magnetic sensor is connected to a side of the case facing the upper surface, and includes an NVC diamond sensor, a green LED light emitting section that inputs light to the NVC diamond sensor, and a light receiving section that can detect light emission from the NVC diamond sensor. including
The microphone according to claim 1.
The vibrating body is made of a soft material,
further comprising a case in which the soft material is laminated on a side surface and the magnetic sensor is enclosed in the case to separate the microphone from the outside;
The magnetic sensor is connected to a side of the case perpendicular to the side surface, and includes an NVC diamond sensor, a green LED light emitting section that inputs light to the NVC diamond sensor, and a light receiving section that can detect light emission from the NVC diamond sensor. including
The microphone according to claim 1.
further comprising a first case and a second case,
The vibrating body is a diaphragm sandwiched between the first case and the second case inside the first case and the second case,
The magnetic sensor is attached to either the first case or the second case, and is isolated from the outside of the microphone by being subjected to waterproof and pressure-resistant treatment.
The microphone according to claim 1.
A side of the diaphragm facing the first case communicates with the outside of the first case via a hole provided in the first case,
A side of the diaphragm facing the second case communicates with the outside of the second case through a hole provided in the second case.
The microphone according to claim 8.
comprising a base plate and a microphone unit disposed on the base plate,
The microphone unit has the configuration according to claim 1.
microphone.