JP2004032314A - Microphone array - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate the positioning of a microphone, hold the microphone in a stabilized state, and suppress the turbulence of a sound field to the minimum. <P>SOLUTION: Through-holes 8 arranged uniformly longitudinally and laterally are formed in a mount plate 4 on which a microphone 2 is mounted. Each through-hole 8 is configured into a square shape having one side substantially equal to the diameter of the microphone, to the interior of which there is stuck a rubber member for holding the microphone resiliently. The microphones of a predetermined number are inserted into the through-holes 8 positioned at sound pressure measurement points and are positioned to form a microphone array. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a microphone array, and more particularly to an improvement in a microphone array suitable for simultaneously measuring sound pressure at multiple points.
[0002]
[Prior art]
2. Description of the Related Art A microphone array technology for arranging microphones along a plane or a curved surface and simultaneously measuring sound pressure at multiple points is used in many situations. In using a microphone array, it is necessary to hold the microphone at a desired position in the sound field in a stable state, and to minimize disturbance of the sound field. Further, in consideration of convenience, it is desirable that the position of the microphone can be easily changed.
[0003]
FIG. 11 is a schematic configuration diagram of a conventional microphone array. In this conventional example, several frames 52 are provided on a stand 50, and a plurality of microphone holders 54 are attached to each frame 52 at equal intervals. With such a configuration, sound pressure can be measured at multiple points simultaneously by attaching the microphone 56 to a desired microphone holder 54. Further, if the frame 52 is movable on the stand 50 and the microphone holder 54 is movable on the frame 52, the measurement position can be changed to some extent.
[0004]
[Problems to be solved by the invention]
However, there are many special requests such as arranging microphones diagonally, arranging microphones concentrated in a certain part, or wanting to measure while changing the microphone installation position one by one. In order to change the installation of the microphone every time in response to such a request, the mounting position of the microphone holder or the frame may be changed each time, and the setting is troublesome, and it is difficult to respond more quickly.
[0005]
Generally, in order to dispose an object at a free position in a plane, it is preferable to dispose the object on a “plane” such as a plate material instead of a “line” such as the above-described frame. However, in the microphone array, since it is necessary to measure the sound pressure without disturbing the sound field, a configuration in which the microphones are simply arranged on a plate that does not allow sound to pass cannot work.
[0006]
The present invention has been made to solve the above problems, and an object of the present invention is to provide a microphone array that can easily position a microphone at a desired position and can easily change the arrangement.
[0007]
Another object of the present invention is to provide a microphone array capable of holding a microphone in a stable state.
[0008]
It is another object of the present invention to provide a microphone array capable of minimizing disturbance of a sound field.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a microphone array according to the present invention has a plurality of rod-shaped microphones and a mounting plate for the microphone having a flat surface or a curved surface. A plurality of through holes having the same diameter as the outer diameter of the microphone and arranged in the vertical and horizontal directions are formed, and the microphone is positioned by being inserted into the through hole.
[0010]
In addition, there is provided a holding mechanism for fixing the microphone inserted into the through hole to the mounting plate.
[0011]
Further, the holding mechanism is characterized in that it is formed of an elastic member that is mounted in the through hole and grips the microphone.
[0012]
Alternatively, the holding mechanism is formed by a screw hole penetrating from the outer surface of the mounting plate to the through hole, and a screw screwed into the screw hole to tighten the microphone.
[0013]
Further, a microphone array according to another invention has a plurality of rod-shaped microphones, a mounting plate of the microphone having a flat surface or a curved surface, and a cylindrical microphone holder having an inner diameter equivalent to the outer diameter of the microphone. The mounting plate has a plurality of through-holes, each having a diameter equal to the outer diameter of the microphone, and arranged in the vertical and horizontal directions, and the microphone is inserted into the through-hole together with the microphone holder. It is characterized by being held by being performed.
[0014]
The microphone holder has a first flange fixed to one end of the cylindrical shape, and a second flange detachably attached to the other end of the cylindrical shape, and is inserted into the through hole. The microphone is fixed to the mounting plate by attaching the second flange to the other end of the microphone holder in the state.
[0015]
Further, the microphone holder is formed of an elastic member.
[0016]
Further, in each of the above inventions, the microphone has a stopper for determining an insertion amount of the microphone into the through hole.
[0017]
Further, the stopper is attached to the same position in all the microphones.
[0018]
In each of the above inventions, the mounting plate has a thickness of less than 14.2 mm, and can be formed only in a circular region having a diameter of less than 14.2 mm in a portion where the surface is not penetrated. .
[0019]
Further, in each of the above inventions, the mounting plate has a thickness of less than 8.5 mm, and can be formed only in a circular region having a diameter of less than 8.5 mm in a part where the surface is not penetrated. .
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.
[0021]
Embodiment 1 FIG.
FIG. 1 is a schematic configuration diagram showing a first embodiment of a microphone array according to the present invention, and FIG. 2 is a perspective view showing a microphone in the present embodiment. FIG. 1 shows a flat mounting plate 4 to which the microphone 2 is mounted, and a pair of stands 6 that sandwich the mounting plate 4. FIG. 1 shows a stand 6 capable of holding the mounting plate 4 in a state where the mounting plate 4 can be adjusted to an angle, and the structure of the stand 6 itself is set at an installation location, a sound pressure measurement direction and an angle. It is not limited to this as long as it can be performed.
[0022]
The mounting plate 4 in the present embodiment is an aluminum flat plate having a size of 232 mm square and a thickness of 5 mm, and a plurality of through holes 8 are formed so as to be evenly arranged in the vertical and horizontal directions. The mounting position of the microphone 2 is determined by being inserted into the through hole 8, and is held. The microphone 2 in the present embodiment is formed in a round bar shape as shown in FIG. 2, and has a diameter of 1/4 inch (6.35 mm). Therefore, each through-hole 8 is formed as a square hole having one side of approximately 6.35 mm according to the diameter of the microphone 2. Since the through-hole 8 only needs to be able to insert the microphone 2, it may be circular or another shape. In consideration of the manufacturing process, cost, and convenience of the mounting plate 4, all the through-holes 8 will usually have the same shape, but they do not always need to have the same size and shape. Further, in the present embodiment, the through holes 8 are provided at intervals of 5 mm. As a result, 20 × 20 through holes 8 are formed. The dimensions such as the size of the through hole 8 and the thickness of the mounting plate 4 will be described later in detail. In the present embodiment, the mounting plate 4 has a flat plate shape, but may have a curved surface. The shape is determined by the environment in which the sound pressure is measured.
[0023]
The microphone 2 is provided with a sound collecting surface 10 on one end and a cable 12 for outputting a sound signal on the other end, and a stopper 14 is provided between them. FIG. 3 shows a state in which the microphone 2 inserted into the through hole 8 is viewed from the side of the mounting plate 4. In the present embodiment, the microphone 2 is inserted into the through hole 8 from the back of the mounting plate 4, but the stopper 14 determines the insertion amount of the microphone 2 into the through hole 8 as is apparent from FIG. Therefore, the mounting position of the stopper 14 to the microphone 2 may be determined according to the length from the sound collecting surface 10 to the stopper 14 and the thickness of the mounting plate 4. If the stoppers 14 are provided at the same position for all the microphones 2, the distance relationship between the mounting plate 4 and the sound collecting surface 10 of the microphones 2 can be set to the same state, so that the sound pressure measurement can be performed with high accuracy. it can.
[0024]
As is clear from the above description, the stopper 14 may be protruded from the cylindrical main body of the microphone 2 and the entire diameter of the microphone 2 including the stopper 14 may be larger than the diameter of the through hole 8. Therefore, in the present embodiment, the stopper 14 is a ring-shaped flange, but it may be configured such that one or more simple protrusions are provided. Further, the stopper 14 may be configured to be able to slide in the longitudinal direction with respect to the main body of the microphone 2 so that the insertion amount of the microphone 2, that is, the protrusion amount of the sound collection surface 10 from the mounting plate 4 can be adjusted.
[0025]
FIG. 4 is a view when the microphone 2 is inserted into the through hole 8 when viewed from the front of the mounting plate 4. A rubber material 16 is attached to the inner wall of the through hole 8 as an elastic member. When the cylindrical microphone 2 is inserted into the rectangular through hole 8, there is a gap around it, but in the present embodiment, the gap is filled with the rubber material 16, and the microphone 2 is resilient by its elastic force. To grip. Thereby, the microphone 2 can be reliably held in the through hole 8, and shake due to vibration or the like inside the through hole 8 can be prevented.
[0026]
In the above configuration, when measuring the sound pressure in a certain sound field, the mounting plate 4 is installed at the measurement location. Then, the microphone 2 is inserted into the through hole 8 located at the sound pressure measurement point. FIG. 5 shows an example in which the microphone 2 is attached to the through hole 8. Even when the obstacle 17 exists as in this example, the 20 microphones 2 are placed at positions avoiding the obstacle 17. The sound pressure can be measured at multiple points at the same time. Of course, it is not necessary to arrange them regularly, and the sound pressure can be measured at a desired point. In FIG. 5, the stand is omitted for convenience.
[0027]
As described above, in the present embodiment, the microphone 2 can be easily positioned in the sound field only by inserting the microphone 2 into the through hole 8 located at the measurement point on the installed mounting plate 4. The microphone 2 is held in a stable state by the rubber material 16 in the through hole 8. Further, even when it is desired to measure the sound pressure at different points on the mounting plate 4, it is only necessary to remove the microphone 2 inserted in the through hole 8 from the through hole 8 and insert the microphone 2 into the desired changed position into the through hole 8. The measurement position can be easily changed.
[0028]
Further, a large number of through-holes 8 provided in the mounting plate 2 in the present embodiment are naturally provided to function as mounting portions for the microphone 2, but not only that, but also disturbance of the sound field is minimized. The effect of suppressing can also be achieved.
[0029]
That is, as described above, the mounting plate 4 used in the present embodiment was an aluminum plate having a thickness of 5 mm, and the interval between the through holes 8 was 5 mm. Here, the thickness of the mounting plate 4 is less than 14.2 mm, and an interval where a circle having a diameter of 14.2 mm or more cannot be formed in a portion between the through holes 8, that is, a portion that is not penetrated, in other words, is not penetrated. If a through-hole 8 is provided so that the diameter of the circle is less than 14.2 mm when a circle is drawn on the portion, a wavelength range (18.3 mm, 12 KHz) that can be measured by a normal sound level meter is passed. And does not disturb the measurement result in normal acoustic measurement. Further, if the thickness of the mounting plate 4 is less than 8.5 mm and the through holes 8 are provided in portions where the surface is not penetrated so that the diameter is less than 8.5 mm, the minimum wavelength in the audible range (17 mm) , 20 KHz) and can be used for almost all acoustic measurements.
[0030]
In the above embodiment, the through holes 8 are all the same size in accordance with the diameter of the microphone 2 and are regularly provided in a lattice shape. That is, the microphones 2 are attached to all the through holes 8. Thereby, the microphones 2 can be mounted at desired positions on the mounting plate 4 such as arranging the microphones 2 in an oblique direction. However, if the mounting position of the microphone 2 is specified to some extent, the size of the through hole 8 provided at the unspecified mounting position can be freely set without depending on the diameter of the microphone 2. . Also, the arrangement of the through holes 8 does not need to be regular at regular intervals.
[0031]
Further, in the present embodiment, the rubber member 16 is used as the elastic member provided inside the through hole 8, but another member having an elastic force such as a sponge may be used. The same applies to the material of the elastic member in other embodiments described later.
[0032]
Embodiment 2 FIG.
FIG. 6 is an enlarged view of a structure for fixing the microphone inserted into the through-hole in the present embodiment when the mounting plate is cut away and viewed from the side. In the first embodiment, the rubber material is provided in the through-hole 8, and the microphone 2 is held by the elastic force. In the present embodiment, as a mechanism for holding the microphone 2, the microphone 2 is screwed into the screw hole 18 from the rear surface 4 a of the mounting plate 4 to the through hole 8 and screwed into the screw hole 18 to tighten the microphone 2. It is characterized in that a holding screw 20 is provided. Although the entrance of the screw hole 18 can be provided on the front side of the mounting plate 4, it is provided on the back surface 4a in order to suppress disturbance of the sound field. The screw hole 18 has a diameter of 1 mm, and is fixed by pressing the slope of the top end of the screw 20 against the microphone 2 as shown in FIG.
[0033]
According to the present embodiment, since the microphone 2 is fixed using the screw 20, the microphone 2 can be held more firmly, and it is not necessary to separately attach an elastic member such as a rubber material inside the through hole 8. Therefore, the opening area of the through hole 8 is not reduced. Therefore, sound can be transmitted without disturbing the sound field.
[0034]
Embodiment 3 FIG.
FIG. 7 is a diagram illustrating a microphone holder that constitutes a holding mechanism of the microphone 2 according to the present embodiment. The microphone holder 22 and the microphone 2 are illustrated. FIG. 8 is a diagram showing a method of attaching the microphone holder 22 to the attachment plate 4. In the first embodiment, a rubber material is used, and in the second embodiment, a screw is used to hold the microphone 2 inserted into the through hole 8. The present embodiment is characterized in that the microphone 2 is held by the microphone holder 22.
[0035]
The microphone holder 22 includes a holder main body 24 and a nut 26 for fixing the holder main body 24 inserted into the through hole 8 to the mounting plate 4 by screwing. The holder main body 24 has a cylindrical portion 28 into which the microphone 2 is inserted, and stoppers 30 and screw threads 32 provided at both ends of the cylindrical portion 28. Since the diameter of the microphone 2 is 6.35 mm, the inner diameter of the microphone holder 24 is set to 6.35 mm according to the diameter. The configurations of the mounting plate 4 and the through holes 8 in the present embodiment may be the same as those in the first embodiment, but the dimensions of the microphone holder 22 are different by the thickness. In the present embodiment, the through hole 8 is 8.35 mm square and the mounting plate 4 is 272 mm × 272 mm in consideration of the thickness of the microphone holder 22. Note that the thickness of the mounting plate 4 may be kept at 5 mm. In this embodiment, similarly to Embodiment 1, the thickness of the mounting plate 4 is less than 8.5 mm, and the portion of the surface not penetrated has a diameter of less than 8.5 mm. Since the hole 8 is provided, it is possible to pass the lowest audible wavelength (17 mm, 20 KHz).
[0036]
In the above configuration, when forming the microphone array, the holder main body 22 is inserted from the back side of the mounting plate 4 into the through hole 8 for mounting the microphone 2 as shown in FIG. In FIG. 8, a part of the mounting plate 4 is cut away so as to be viewed from the side direction, and the microphone holder 22 is cut away for easy understanding of the mounting structure on the mounting plate 4. Since the stopper 30 is formed in the holder main body 24, the insertion amount is fixed. When the holder main body 22 is inserted, the screw thread 32 protrudes from the surface of the mounting plate 4. In other words, the length of the cylindrical portion 28 is determined so that the screw thread 32 protrudes from the surface of the mounting plate 4. Then, the nut 26 is screwed into the holder main body 24 with the holder main body 22 inserted into the through hole 8. Thereby, the stopper 30 and the nut 26 of the microphone holder 22 act as a flange, and the microphone holder 22 can be fixed to the mounting plate 4. Then, the microphone array is formed by inserting the microphone holon 2 into the microphone holder 22.
[0037]
According to the present embodiment, the microphone holon 2 can be attached to the attachment plate 4 by inserting it into the microphone holder 22. In order to hold the microphone 2, the longer the length of the cylindrical portion 28 is, the more stable it can be held. Therefore, the cylindrical portion 28 may be configured to extend further from the stopper 30 to the rear. If the sound field is not disturbed, it can be extended to the surface side of the mounting plate 4 structurally.
[0038]
Embodiment 4 FIG.
FIG. 9 is a diagram showing a microphone holder constituting the holding mechanism of the microphone 2 in the present embodiment, and shows a state in which the microphone holder 34 is inserted into the through hole and attached to the mounting plate 4. FIG. 9 is a view of the mounting plate 4 as seen from the side direction, similarly to FIG. 8, and a part of the mounting plate 4 is cut out and the microphone holder 34 is cut and illustrated so that the mounting structure can be easily understood.
[0039]
The present embodiment is characterized in that the microphone holder 34 is formed of an elastic member such as a rubber material. The outer diameter of the portion of the microphone holder 34 inserted into the through hole is substantially the same as or slightly larger than the inner diameter of the through hole, and the microphone holder 34 is press-fitted into the through hole. In the inserted state, the microphone holder 34 is fixed to the mounting plate 4 by the elastic force of the elastic member. Therefore, in the present embodiment, since a structure for screwing is unnecessary, a portion protruding to the surface side of the mounting plate 4 is cut.
[0040]
By making the inner diameter of the microphone holder 34 substantially the same as or slightly smaller than the outer diameter of the microphone 2, the microphone 2 can be reliably held by the elastic force of the elastic member forming the microphone holder 34.
[0041]
Embodiment 5 FIG.
FIG. 10 is a diagram showing a microphone holder constituting a microphone holding mechanism according to the present embodiment. In the present embodiment, when a screw hole 36 is provided in advance around the through hole 8, the microphone holder 38 is mounted using the screw hole 36. Therefore, a projecting piece 40 is provided at a position corresponding to the screw hole 36 from the ring-shaped main body of the microphone holder 38, and a screw hole is formed in each projecting piece 40. The inner diameter of the ring forming the main body is equal to the outer diameter of the microphone 2. In this configuration, the microphone holder 38 is fixed to the mounting plate 4 with a screw (not shown), and the microphone 2 is inserted into the through hole 8 via the fixed microphone holder 38.
[0042]
Since the microphone holder 38 is provided on the surface of the mounting plate 4 where the screw holes 36 are provided, the microphone holder 38 is mounted on the front surface, the back surface, or both surfaces of the mounting plate 4. In order to exhibit the function of the microphone 2 as a holding mechanism, it is effective to have a certain thickness. Of course, when it is mounted on the front side of the mounting plate 4, it is necessary that the sound field is not disturbed.
[0043]
【The invention's effect】
According to the present invention, a mounting plate having a plurality of through holes arranged in the vertical and horizontal directions is provided, and a microphone array can be formed by inserting a microphone into a desired through hole. The microphone can be easily positioned and mounted within. Also, even when it is desired to measure the sound pressure at different points on the mounting plate, simply remove the microphone inserted in the through-hole from the through-hole and insert it into the through-hole at the desired change position to easily set the measurement position. Can be changed.
[0044]
Further, since the sound passes through the through-hole in which the microphone is not inserted, disturbance of the sound field can be suppressed to a minimum.
[0045]
Further, by providing a mechanism for holding the microphone inserted into the through hole, the microphone in the inserted state can be reliably held.
[0046]
Further, since the microphone inserted into the through hole is fixed by the screw passing through the screw hole penetrating from the outer surface of the mounting plate to the through hole, it is not necessary to provide a separate holding mechanism in the through structure. That is, the microphone can be more firmly held by the screw, and disturbance of sound passing through the through-hole to which the microphone is not attached can be suppressed as much as possible.
[0047]
Further, by providing the stopper, positioning in the near and far directions with respect to the sound source can be easily and reliably performed.
[0048]
In addition, the thickness of the mounting plate is less than 14.2 mm, and only a circular area with a diameter of less than 14.2 mm can be formed in the part where the surface is not penetrated, so that it can be measured with a normal sound level meter Wavelength range (18.3 mm, 12 KHz), and does not disturb the measurement result in normal acoustic measurement.
[0049]
Further, the thickness of the mounting plate is set to less than 8.5 mm, and only a circular region having a diameter of less than 8.5 mm can be formed in a part where the surface is not penetrated. 20 KHz) and can be used for almost all acoustic measurements.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing Embodiment 1 of a microphone array according to the present invention.
FIG. 2 is a perspective view showing a microphone according to the first embodiment.
FIG. 3 is a diagram when the microphone inserted into the through hole in the first embodiment is viewed from the side of the mounting plate.
FIG. 4 is a diagram when the microphone inserted into the through hole in the first embodiment is viewed from the front of the mounting plate.
FIG. 5 is a diagram showing an example of an arrangement of microphones when an obstacle is placed in front of a mounting plate in the first embodiment.
FIG. 6 is a diagram when a structure for fixing a microphone inserted into a through hole according to the second embodiment is viewed from the side of a mounting plate.
FIG. 7 is a diagram showing a microphone holder according to a third embodiment.
FIG. 8 is a diagram for explaining a method of attaching a microphone holder to an attachment plate in a third embodiment.
FIG. 9 is a side sectional view of a microphone holder according to a fourth embodiment.
FIG. 10 is an external view showing a microphone holder according to a fifth embodiment.
FIG. 11 is a schematic configuration diagram showing a conventional microphone array.
[Explanation of symbols]
2 microphone, 4 mounting plate, 6 stand, 8 through hole, 10 sound collecting surface, 12 cable, 14, 30 stopper, 16 rubber material, 18, 36 screw hole, 20 screw, 22, 34, 38 microphone holder, 24 holder Body, 26 nuts, 28 barrels, 32 threads, 40 projecting pieces.

Claims (11)

A plurality of rod-shaped microphones,
A mounting plate for the microphone having a flat or curved surface,
Has,
The mounting plate has a plurality of through holes, each having a diameter equal to the outer diameter of the microphone, and arranged in a vertical and horizontal direction,
The microphone array is characterized in that the microphone is positioned by being inserted into the through hole. The microphone array according to claim 1,
A microphone array having a holding mechanism for fixing the microphone inserted into the through hole to the mounting plate. The microphone array according to claim 2,
The microphone array, wherein the holding mechanism is formed of an elastic member attached to the through hole and gripping the microphone. The microphone array according to claim 2,
A microphone array, wherein the holding mechanism is formed by a screw hole penetrating from an outer surface of the mounting plate to the through hole, and a screw screwed into the screw hole to tighten the microphone. A plurality of rod-shaped microphones,
A mounting plate for the microphone having a flat or curved surface,
A cylindrical microphone holder having an inner diameter equivalent to the outer diameter of the microphone,
Has,
The mounting plate has a plurality of through holes, each having a diameter equal to the outer diameter of the microphone, and arranged in a vertical and horizontal direction,
The microphone array is characterized in that the microphone is held by being inserted into the through hole together with the microphone holder. The microphone array according to claim 5,
The microphone holder,
A first flange fixed to one end of the cylindrical shape,
A second flange detachably attached to the other end of the cylindrical shape,
Wherein the microphone is fixed to the mounting plate by attaching the second flange to the other end of the microphone holder while being inserted into the through hole. The microphone array according to claim 5,
The microphone array, wherein the microphone holder is formed of an elastic member. The microphone array according to any one of claims 1 to 7,
The microphone array according to claim 1, wherein the microphone has a stopper that determines an insertion amount of the microphone into the through hole. The microphone array according to claim 8,
The microphone array, wherein the stopper is attached to the same position in all the microphones. The microphone array according to any one of claims 1 to 9,
The microphone array, wherein the mounting plate has a thickness of less than 14.2 mm and can form only a circular area having a diameter of less than 14.2 mm in a part of the surface where the mounting plate is not penetrated. The microphone array according to any one of claims 1 to 9,
The microphone array, wherein the mounting plate has a thickness of less than 8.5 mm, and can form only a circular region having a diameter of less than 8.5 mm in a part where the surface is not penetrated.

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