close

Вход

Забыли?

вход по аккаунту

?

JP2008103982

код для вставкиСкачать
Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JP2008103982
An object of the present invention is to make it possible to easily attach an acoustic resistance
material when using a microphone case itself as an acoustic tube in order to use a microphone
unit with a larger diameter. In a narrow directional microphone provided with a cylindrical
acoustic tube having a sound wave introduction port covered with an acoustic resistance material
on a tube wall, the cylindrical microphone in which a unidirectional microphone unit 30 is
accommodated The case itself is directed forward of the front acoustic terminal of the unit and
extended by a length corresponding to the desired acoustic tube to form an acoustic tube portion
10C, and the acoustic wave inlet 110 is pierced at a predetermined portion of the tube wall of the
acoustic tube portion 10C. The groove 120 is formed on the outer wall side of the acoustic pipe
portion 10C so that the step 120a is formed around the sound wave introduction port 110, and
the acoustic resistance material 130 covering the sound wave introduction port 110 is disposed
on the step 120a. A protective net 140 that is preferably water repellent treated to cover the
acoustic resistance material 130 is disposed in the recessed groove 120. [Selected figure] Figure
2
Narrow directional microphone
[0001]
The present invention relates to a narrow directional microphone having an acoustic tube and
also called a gun microphone, and more particularly to a narrow directional microphone using
the cylindrical microphone case itself of the microphone unit as an acoustic tube.
[0002]
03-05-2019
1
In a narrow directional microphone using an acoustic tube, a long acoustic tube is provided on
the front acoustic terminal side of the unidirectional microphone unit.
The acoustic tube has an acoustic wave inlet port covered with an acoustic resistance material on
the tube wall, and narrows the directivity of the unidirectional microphone unit by taking in the
acoustic wave from the acoustic wave inlet port (for example, , Patent Document 1).
[0003]
An example thereof will be described with reference to FIGS. 4 and 5. FIG. 4 is a simplified
sectional view showing an internal structure showing a conventional narrow directional
microphone, and FIG. 5 is an enlarged sectional view taken along the line B--B of FIG.
[0004]
As shown in FIG. 4, in the conventional narrow directional microphone 1B, a cylindrical
microphone case 10 made of a metal material which is longer than a normal microphone is used.
The tip 10f on the left end side of the microphone case 10 in FIG. 4 is open, and in this example,
the opening 11 is covered with a cap 11 having an acoustic resistance material 11a such as a
sponge material.
[0005]
An output connector 50 is integrally attached to the rear end 10r on the right end side of the
microphone case 10 in FIG. Usually, as the output connector 50, a 3-pin type output connector
50 defined in EIAJ RC-5236 "Latch lock type round connector for audio equipment" is used.
[0006]
As the microphone unit, an electrostatic type unidirectional microphone unit 30 having a front
acoustic terminal 31 and a rear acoustic terminal 32 is used. The unidirectional microphone unit
03-05-2019
2
30 is fixed to a predetermined portion in the microphone case 10 via a support member 41 made
of synthetic resin.
[0007]
In the microphone case 10, the unidirectional tube unit 30 includes an acoustic tube housing
portion 10A on the tip 10f side where the acoustic tube 20 is housed and a power module
portion 10B on the rear end 10r side where the circuit board 42 is housed. It is divided.
[0008]
The acoustic tube 20 is inserted from the tip end 10f side of the microphone case 10 until the
tube end at the rear end is fitted around the front acoustic terminal 31 of the unidirectional
microphone unit 30, and then screwed.
[0009]
Although not shown, an audio output circuit including an FET (field effect transistor) as an
impedance converter, a power supply circuit, etc. is mounted on the circuit board 42, and a
unidirectional directivity microphone unit 30 is mounted on the gate of the FET. Is connected via
a leaf spring contact 43.
Further, the audio output circuit of the circuit board 42 is connected to the output connector 50.
[0010]
Referring to the cross-sectional view of FIG. 5, a circular or elongated sound wave inlet 21 is
drilled at two locations facing, for example, 180 ° in the tube wall of the acoustic tube 20. An
acoustic resistance material 22 is attached to cover the inlet 21.
[0011]
Although not shown, in general, the plurality of sound wave inlets 21 are arranged in a line along
the axial direction of the acoustic tube 20.
03-05-2019
3
Moreover, a felt material, a non-woven fabric, or the like is used as the acoustic resistance
material 22.
In the outermost periphery of the acoustic tube 20, a protection net 22 formed of a wire mesh or
the like for protecting the acoustic resistance material 22 is provided over the entire
circumference in this example.
[0012]
In this state, the acoustic tube 20 is inserted into the acoustic tube storage portion 10A of the
microphone case 10. However, in the tube wall of the acoustic tube storage portion 10A, the
opening 12 larger than the sound inlet 21 is a circle as a slit hole. It is formed along the
circumferential direction. Although not shown, a sound wave introduction port for the rear
acoustic terminal 32 is formed on the rear end side of the acoustic tube housing 10A.
[0013]
Japanese Patent Application Laid-Open No. 62-118698
[0014]
According to the above conventional example, since the acoustic tube 20 is finally inserted into
the acoustic tube storage portion 10A of the microphone case 10, the acoustic resistance
material 22 covering the acoustic wave inlet 21 is formed on the outer wall of the acoustic tube
20. The attachment work can be easily performed, but there are the following problems to be
solved.
[0015]
That is, since the front acoustic terminal 31 of the unidirectional microphone unit 30 is located
in the rear end portion of the acoustic tube 20, it is necessary to use a unit having a diameter
smaller than the inner diameter of the acoustic tube 20. However, doing so reduces the effective
vibration area of the unit, and the sensitivity decreases accordingly.
[0016]
As an example, when the outer diameter of the microphone case 10 is 21 mm, the inner diameter
is 19 mm, the outer diameter of the acoustic tube 20 is 18 mm, and the inner diameter is 16 mm,
03-05-2019
4
the outer diameter of the usable unit is about 14 mm.
[0017]
In the above example, when the acoustic tube housing portion 10A of the microphone case 10 is
an acoustic tube, a unit with an outer diameter of 18 mm can be used at the maximum in the
above example, and the effective vibration area is about It can be increased by 60%, and the
sensitivity and the S / N ratio can be improved accordingly.
[0018]
However, in this case, when the acoustic resistance material is attached to the outer wall surface
side of the acoustic tube housing 10A, not only the appearance is not good, but damage to the
acoustic resistance material due to mischief (for example, sticking with a pen tip), acoustic
resistance material Problems such as performance deterioration occur due to the infiltration of
droplets such as rainwater into the housing.
[0019]
In order to solve this point, the acoustic resistance material may be attached to the inner wall
surface side of the acoustic tube storage portion 10A, but as a practical matter, the acoustic
resistance material is attached to the inner wall surface side of the acoustic tube storage portion
10A. It is not easy to do, and in particular it is extremely difficult to make longer and more
directional sharp sound tubes.
[0020]
Therefore, the object of the present invention is to make it possible to use a microphone unit
with a larger diameter, so that when using the microphone case itself as an acoustic tube, the
attachment work of the acoustic resistance material can be easily performed, and the design
looks good In addition, it is desirable to be able to protect the acoustic resistance material from
droplets and the like.
[0021]
In order to solve the above problems, the invention according to claim 1 is a cylindrical acoustic
pipe having a sound wave inlet port covered with an acoustic resistance material on the pipe wall
on the front acoustic terminal side of the unidirectional microphone unit. In the narrow
directional microphone provided with the above, the cylindrical microphone case itself in which
the unidirectional microphone unit is accommodated is extended forward by the length
corresponding to the acoustic tube toward the front of the front acoustic terminal. An acoustic
03-05-2019
5
pipe portion is formed, the sound wave introduction port is bored in a predetermined portion of
the pipe wall of the acoustic pipe portion, and a recessed groove is formed so that a step is
formed around the sound wave introduction port on the outer wall side of the acoustic pipe
portion. The acoustic resistance material covering the sound wave introduction port is disposed
in the step portion, and a protective net covering the acoustic resistance material is disposed in
the recessed groove.
[0022]
The invention according to claim 2 is characterized in that in the narrow directional microphone
of the above-mentioned claim 1, the protective net is subjected to a water repellent treatment.
[0023]
According to the invention as set forth in claim 1, the cylindrical microphone case itself in which
the unidirectional microphone unit is housed is equivalent to an acoustic tube with the front
acoustic terminal of the unidirectional microphone unit facing forward. The sound pipe is
extended by a length to form an acoustic pipe part, and a sound wave introduction port is bored
in a predetermined part of the pipe wall of the acoustic pipe part, and a recess is formed so that a
step part is produced around the sound wave introduction port on the outer wall side of the
acoustic pipe part. A groove is formed, an acoustic resistance material covering the sound wave
introduction port is disposed in the step portion, and a protective net covering the acoustic
resistance material is disposed in the recessed groove, so that the microphone case itself is used
as an acoustic tube The attachment work of the acoustic resistance material can be easily
performed, and the appearance is good also in design, and furthermore, the acoustic resistance
material can be protected from droplets and the like.
[0024]
Further, according to the second aspect of the present invention, since the protective net is
subjected to the water repellent treatment, the droplets such as rainwater hardly enter into the
ditch, so the acoustic resistance material is a liquid such as rainwater. It can protect more reliably
from drops and maintain the initial performance as a narrow directional microphone over a long
period of time.
[0025]
Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 3,
but the present invention is not limited to this.
03-05-2019
6
1 is a simplified sectional view showing a narrow directional microphone according to an
embodiment of the present invention, FIG. 2 is an enlarged sectional view taken along the line AA of FIG. 1, FIG. 3 is a sonic wave inlet of FIG. It is a side view showing a portion of.
The same reference numerals as in the prior art described with reference to FIGS. 4 and 5 denote
the same components as those in the prior art described above.
[0026]
As shown in FIG. 1, also in the narrow directional microphone 1A according to the present
invention, a cylindrical microphone case 10 made of a metal material such as a brass alloy which
is longer than a normal microphone is used.
The front end 10f on the left end side of the microphone case 10 in FIG. 1 is open, and in this
example, the opening 11 is covered with a cap 11 having an acoustic resistance material 11a
such as a sponge material.
[0027]
An output connector 50 is integrally attached to the rear end 10r on the right end side of the
microphone case 10 in FIG.
The output connector 50 may be an output connector defined in EIAJ RC-5236 "Latch Lock
Round Connector for Audio Equipment".
The output connector 50 is connected to a phantom power supply (not shown).
[0028]
03-05-2019
7
Also in the present invention, an electrostatic type unidirectional microphone unit 30 having a
front acoustic terminal 31 and a rear acoustic terminal 32 is used as the microphone unit.
The unidirectional microphone unit 30 is fixed to a predetermined portion in the microphone
case 10 via a support member 41 made of synthetic resin.
[0029]
The inside of the microphone case 10 is divided by the unidirectional microphone unit 30 into an
acoustic pipe portion 10C on the tip 10f side and a power module portion 10B on the rear end
10r side where the circuit board 42 is accommodated.
[0030]
That is, the acoustic tube portion 10C is a portion extended toward the front of the front acoustic
terminal 31 of the unidirectional microphone unit 30 by a length corresponding to the desired
acoustic tube, and the conventional example described above Corresponds to the acoustic tube
storage 10A in FIG.
[0031]
Although not shown, an audio output circuit including an FET (field effect transistor) as an
impedance converter, a power supply circuit, etc. is mounted on the circuit board 42, and a
unidirectional directivity microphone unit 30 is mounted on the gate of the FET. Is connected via
a leaf spring contact 43.
Further, the audio output circuit of the circuit board 42 is connected to the output connector 50.
[0032]
With reference to the cross-sectional view of FIG. 2 and the side view of FIG. 3, in this example, a
long hole-like sound inlet 110 is drilled at two locations facing 180 ° in the tube wall of the
acoustic tube portion 10C. .
03-05-2019
8
The sound wave introduction port 110 may be a round hole, but in any case, it is preferable that
a plurality of the sound wave introduction ports 110 be arranged in a line along the axial
direction of the acoustic pipe portion 10C.
[0033]
In some cases, the sound wave introduction port 110 may be a series of slit holes extending
substantially the entire length of the acoustic pipe portion 10C.
As another example, the sound wave introduction port 110 may be a long hole (slit hole) along
the circumferential direction of the acoustic pipe portion 10C.
[0034]
According to the present invention, the concave groove 120 is formed on the outer wall side of
the acoustic pipe portion 10C so that the step portion 120a is generated around the sound wave
introduction port 110.
The stepped portion 120 a is also the bottom of the recessed groove 120, and the acoustic
resistance material 130 covering the sound wave introduction port 110 is disposed on the
stepped portion 120 a.
As the acoustic resistance material 130, a felt material, a non-woven fabric, or the like may be
used as in the prior art.
[0035]
After the step portion 120 a of the acoustic resistance material 130 is disposed, a protective net
140 for protecting the acoustic resistance material 130 is disposed in the recessed groove 120.
A wire mesh is preferably used for the protective mesh 140, but a punching plate made of a
03-05-2019
9
metal plate or a synthetic resin plate may be used.
In any case, in order to prevent droplets such as rain water from entering the concave groove
120, it is preferable that a water repellent treatment be performed.
[0036]
According to the present invention, since a part of the microphone case 10 is the acoustic tube
portion 10C, and the unidirectional microphone unit 30 is accommodated in the acoustic tube
portion 10C, the acoustic tube 20 in the above-described conventional example is unnecessary.
For the unidirectional microphone unit 30, a unit having a large aperture, ie, a large effective
vibration area can be used.
[0037]
In addition, since the acoustic resistance material 130 can be attached to the sound wave
introduction port 110 from the outer surface side of the acoustic pipe portion 10C, the work can
be easily performed.
In addition, since the acoustic resistance material 130 is blinded by the protective net 140, it has
a good design appearance.
Furthermore, since the liquid such as rainwater does not penetrate into the acoustic resistance
material 130, performance deterioration can also be prevented.
[0038]
FIG. 2 is a simplified cross-sectional view showing a narrow directional microphone according to
an embodiment of the present invention. The AA expanded sectional view of FIG. The side view
which shows the part of the sound wave introduction port of FIG. Sectional drawing which
simplified the internal structure which shows the conventional narrow directivity microphone.
FIG. 5 is an enlarged cross-sectional view taken along line B-B of FIG. 4.
03-05-2019
10
Explanation of sign
[0039]
1A narrow directivity microphone 10 microphone case 10B power module portion 10C acoustic
pipe portion 110 sound wave introduction port 120 recessed groove 120a stepped portion 130
acoustic resistance material 140 protective network 30 unidirectional microphone unit 31 front
acoustic terminal 32 rear acoustic terminal 42 Circuit board 50 output connector
03-05-2019
11
Документ
Категория
Без категории
Просмотров
0
Размер файла
20 Кб
Теги
jp2008103982
1/--страниц
Пожаловаться на содержимое документа