close

Вход

Забыли?

вход по аккаунту

?

JP2006197070

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 JP2006197070
An object of the present invention is to ensure sensitivity by ensuring that the diaphragm is easy
to move when receiving a sound pressure and has a low frequency response and that the area of
the center dome can be sufficiently large even with a small aperture. Get a dynamic microphone
that can A vibration plate receives vibration and vibrates, and a conversion unit that electrically
acts on the vibration plate to convert the vibration into an electric signal. The diaphragm 6 has
an outer peripheral portion in line contact with the support, and the line contact portion is fixed
to the support by an adhesive 66. The adhesive 66 is a resilient adhesive even after curing. The
diaphragm 6 has a center dome portion 61 and a sub dome portion 62 on the outer peripheral
side thereof, and the outer peripheral edge portion of the sub dome portion 62 is fixed to the
support by adhesion. [Selected figure] Figure 1
ダイナミックマイクロホン
[0001]
The present invention relates to a dynamic microphone capable of securing frequency response
up to low frequencies and capable of enhancing sensitivity.
[0002]
The dynamic microphone has a magnetic circuit formed of a magnet, a yoke, etc., a diaphragm,
and a voice coil integrally attached to the diaphragm and disposed in a gap in the magnetic
circuit.
13-05-2019
1
When the diaphragm vibrates according to the voice reaching the microphone, the voice coil
vibrates with this and the voice coil crosses the magnetic field formed in the gap while vibrating,
thereby converting the voice from the voice coil into an electrical signal and outputting Be done.
[0003]
An example of a dynamic microphone unit of a conventional general configuration is shown in
FIG. In FIG. 2, a disk-shaped magnet (permanent magnet) 1 is fixed at the center of the inner
bottom surface of the flat circular dish-like yoke 2 by a fixing means such as adhesion. The
magnet 1 is magnetized in the thickness direction (vertical direction in FIG. 2). The thickness
(height) dimension of the magnet 1 is the same as the height of the inner peripheral surface of
the peripheral wall 21 of the yoke 2, and the upper end surface of the magnet 1 and the upper
end surface of the peripheral wall 21 of the yoke 2 are on the same plane. A ring yoke 3 is fixed
to the upper end surface of the peripheral wall 21 of the yoke 2 by a fixing means such as
adhesion. A disc-shaped pole piece 4 is fixed to the upper end surface of the magnet 1 by a fixing
means such as adhesion. The upper end surface of the pole piece 4 and the upper end surface of
the ring yoke 3 are on the same plane. Between the inner circumferential surface of the ring yoke
3 and the outer circumferential surface of the pole piece 4, a gap 5 concentric with the ring yoke
3 and the pole piece 4 is formed with a constant width. The pole piece 4, the ring yoke 3, and the
yoke 2 constitute a magnetic circuit through which the magnetic flux emitted from the magnet 1
passes. That is, the magnetic flux emitted from the magnet 1 passes through the pole piece 4,
passes through the gap 5 to reach the ring yoke 3, and further passes through the yoke 2 and
returns to the magnet 1. Therefore, a magnetic field is formed in the gap 5.
[0004]
In the gap 5, a voice coil 7 in which a thin conductive wire is wound in a cylindrical shape is
disposed across the magnetic field formed in the gap 5. The voice coil 7 is attached to a
diaphragm 6 made of a film-like material. The configuration of the diaphragm 6 and the voice
coil 7 will be described in more detail. The diaphragm 6 has a center dome portion 61 and a sub
dome portion 62 that elastically supports the center dome portion 61. The boundary between the
center dome portion 61 and the sub dome portion 62 One end of the voice coil 7 is fixed in the
vicinity by means such as adhesion. The vibrating plate 6 also has an adhesive portion 63 of a
fixed width d all around the outer periphery of the sub dome portion 62, and the adhesive
portion 63 is adhered to the adhesive surface 32 formed on the ring yoke 3. The bonding surface
32 formed on the ring yoke 3 is formed stepwise on the inner peripheral side of the peripheral
13-05-2019
2
wall 31 formed on the ring yoke 3 and at a position one step higher than the main body portion
of the ring yoke 3. Therefore, the diaphragm 6 is supported in a state in which the other portions
except the bonding surface 63 float from the ring yoke 3. Also, the voice coil 7 mechanically and
tightly coupled to the diaphragm 6 is located in the gap 5 as described above, and the poles
forming the inner peripheral surface of the ring yoke 3 and the gap 5 constituting the gap 5 It is
supported so as not to contact the outer peripheral surface of the piece 4.
[0005]
When a sound wave reaches the microphone, the diaphragm 6 vibrates according to the sound
wave, and the voice coil 7 vibrates integrally with the diaphragm 6. The voice coil 7 breaks the
magnetic flux in the gap 5 by the vibration of the voice coil 7, and an electric signal according to
the sound wave is generated in the voice coil 7. Thus, the sound wave is converted into an
electrical signal and output from the microphone.
[0006]
The reason why the diaphragm 6 has the center dome portion 61 is to vibrate the voice coil 7
together with the diaphragm 6 with a predetermined rigidity. Further, the reason why the
diaphragm 6 has the sub dome portion 62 is to elastically support the whole diaphragm 6 and to
vibrate the diaphragm 6 faithfully according to the sound wave.
[0007]
Since the center dome portion 61 of the diaphragm 6 vibrates together with the voice coil 7,
increasing the area of the center dome portion 61 can increase the sensitivity of the microphone.
Since the control system of the unidirectional dynamic microphone is mainly mass control,
lowering the low resonance frequency of the diaphragm 6 enables sound collection at a low
frequency. In order to lower the low frequency resonance frequency, (1) The voice coil 6 is made
heavier. (2) The elastic force of the sub dome portion 62 is weakened by, for example, weakening
the stiffness. There is a way. However, in the method of making the voice coil 6 heavier, vibration
noise, that is, handling noise increases when the microphone is held by hand, which is unsuitable
as a hand-held microphone. On the other hand, as a method of weakening the elastic force of the
sub dome portion 62, there is a method of reducing the thickness of this portion or increasing
the radius of curvature of this portion. In addition, since it becomes difficult to support the center
13-05-2019
3
dome portion 61 softly if the area of the sub dome portion 62 is reduced, it is also one method to
increase the area of the sub dome portion 62.
[0008]
Usually, the outer peripheral edge portion of the diaphragm 6, that is, the bonding portion 63, is
fixed by being planarly bonded and fixed to the yoke 2 or the like constituting the housing of the
microphone unit as in the example shown in FIG. , Patent Document 2). The adhesive margin of
the bonding portion 63 is the width d of the bonding portion 63 in the radial direction, which is
about 1 mm. Therefore, about 2 mm in diameter is secured. Incidentally, in the case of a
microphone unit having a diameter a of 13 mm at the center in the thickness direction of the
voice coil 7, an inner diameter b of the peripheral wall 21 of the yoke 2 of 24 mm, and a
diameter c of 27 mm including the bonded portion 63 of the voice coil 6, d is about 1 mm.
[0009]
From the above, in the case of a microphone unit having a large external shape, securing about 1
mm of the width d in the radial direction of the bonding portion 63 does not matter so much.
However, in a relatively small diameter microphone unit having an outer diameter of 20 mm or
less, by securing the width d of the bonding portion 63 in the radial direction to about 1 mm, a
diameter of 10% or more in diameter is used for bonding the outer peripheral edge portion of the
diaphragm 6 It will be used. At the same time, the area of the center dome portion 61 of the
diaphragm 6 is reduced, which causes a problem that the sensitivity of the microphone is
lowered. In addition, if the area of the sub dome portion 62 is reduced to increase the area of the
center dome portion 61 as much as possible, the elastic force of the sub dome 62 supporting the
center dome portion 61 becomes large (spring becomes hard: stiffness becomes large). It causes
a problem that collecting sound becomes difficult.
[0010]
Further, in the conventional configuration in which the outer peripheral edge portion of the
diaphragm 6 is fixed by adhesion, as shown in FIG. 2, the adhesive 65 protruding from the
adhesive surface 32 is the outer peripheral portion of the sub dome portion 62 of the diaphragm
6 and the ring yoke 3 Spreads and hardens on the inner peripheral surface following the
adhesive surface 32 of the above, and the range in which the movement of the sub dome portion
62 is permitted is restricted and it becomes difficult to move, which also causes a problem that
sound collection of the bass region becomes difficult .
13-05-2019
4
[0011]
As described above, in the small-aperture dynamic microphone unit, in order to make it possible
to collect sound in the low-frequency range, a device is sought that can ensure the effective area
of the center dome portion and sub dome portion of the diaphragm as large as possible. Be
[0012]
Patent Document 1: Japanese Patent Application Laid-Open No. 10-33,791
[0013]
The present invention has been made to solve the problems of the conventional dynamic
microphones as described above, and by devising the support structure of the diaphragm, the
diaphragm has a sound pressure even if it is a small aperture microphone. It is an object of the
present invention to provide a dynamic microphone capable of securing sensitivity by ensuring
that it is easy to move and receives frequency response up to the low frequency and sufficient
area of the center dome portion. Do.
[0014]
The present invention is a dynamic microphone having a diaphragm that receives and vibrates a
sound wave, and a conversion unit that electrically acts on the diaphragm to convert the
vibration into an electrical signal, and the diaphragm is an external The main feature is that the
peripheral portion is in line contact with the support, and the line contact is fixed to the support
by an adhesive.
The adhesive may be a resilient adhesive even after curing.
[0015]
By bringing the outer peripheral edge portion of the diaphragm into line contact with the support
and fixing the line contact portion to the support with an adhesive, the bonding area of the
diaphragm can be reduced, and the movable portion of the diaphragm is correspondingly The
area can be increased, and even in the case of a small-diameter microphone, the frequency
13-05-2019
5
response up to the low frequency can be secured.
In addition, since the bonding area of the diaphragm can be reduced, the area of the portion of
the center dome of the diaphragm can be increased, and the sensitivity of the microphone can
also be enhanced.
If an adhesive having elasticity even after curing is used as the above-mentioned adhesive, the
movement of the diaphragm is permitted to some extent even in the bonded portion, and it
becomes easy to secure the frequency response up to the low region.
[0016]
Hereinafter, an embodiment of a dynamic microphone according to the present invention will be
described with reference to FIG.
The same reference numerals as in the prior art shown in FIG. 2 denote the same parts. In FIG. 1,
a disk-shaped or low-cylindrical magnet (permanent magnet) 1 is fixed to the center of the inner
bottom surface of a flat circular dish-like yoke 2 by a fixing means such as adhesion. The magnet
1 is magnetized in the thickness direction (vertical direction in FIG. 1). The thickness (height)
dimension of the magnet 1 is the same as the height of the inner peripheral surface of the
peripheral wall 21 of the yoke 2, and the upper end surface of the magnet 1 and the upper end
surface of the peripheral wall 21 of the yoke 2 are on the same plane. A ring yoke 3 is fixed to
the upper end surface of the peripheral wall 21 of the yoke 2 by a fixing means such as adhesion.
A disc-shaped pole piece 4 is fixed to the upper end surface of the magnet 1 by a fixing means
such as adhesion. The upper end surface of the pole piece 4 and the upper end surface of the
ring yoke 3 are on the same plane. Between the inner circumferential surface of the ring yoke 3
and the outer circumferential surface of the pole piece 4, a gap 5 concentric with the ring yoke 3
and the pole piece 4 is formed with a constant width. The pole piece 4, the ring yoke 3, and the
yoke 2 constitute a magnetic circuit through which the magnetic flux emitted from the magnet 1
passes. That is, the magnetic flux emitted from the magnet 1 passes through the pole piece 4,
passes through the gap 5 to reach the ring yoke 3, and further passes through the yoke 2 and
returns to the magnet 1. Therefore, a magnetic field is formed in the gap 5.
[0017]
13-05-2019
6
In the gap 5, a voice coil 7 in which a thin conductive wire is wound in a cylindrical shape is
disposed across the magnetic field formed in the gap 5. The voice coil 7 is attached to a
diaphragm 6 made of a film-like material. The configuration of the diaphragm 6 and the voice
coil 7 will be described in more detail. The diaphragm 6 is integrally formed with the center
dome portion 61 in a ring shape along the outer periphery thereof to elastically support the
center dome portion 61 and this. And a sub dome portion 62. The sub dome portion 62 has a
dome shape in cross section. One end side of the voice coil 7 is fixed near the boundary between
the center dome portion 61 and the sub dome portion 62 by means such as adhesion.
[0018]
The ring yoke 3 also functions as a support for the voice coil 7 and is stepped on the inner
peripheral side of the peripheral wall 31 formed in the ring yoke 3 and one step higher than the
main body portion of the ring yoke 3. The outer peripheral edge portion of the voice coil 7 is
bonded to the entire bonding surface 33 formed and formed. However, unlike the conventional
example shown in FIG. 2, the adhesive portion 64 at the outer peripheral edge of the voice coil 7
has a shape in which the dome shape in the cross section of the sub dome portion 62 is
extended. Line contact 33 (in appearance of point contact in the cross section shown in FIG. 1) is
made in a circular arc shape in the circumferential direction. An adhesive 66 is applied along the
line contact portion, and the voice coil 7 is fixed to the ring yoke 3 as a support in the range of
the width f of the adhesive surface 33. The outer peripheral edge portion of the diaphragm 6 is
spaced apart from the bonding surface 33 and the inner peripheral surface of the peripheral wall
31 of the ring yoke 3 except for the portion in line contact with the bonding surface 33. The
adhesive 66 cures within the range of the width f, and the diaphragm 6 is fixed. Therefore, the
adhesive 66 covers the diaphragm 66 from the upper and lower surfaces of the outer peripheral
edge thereof and is fixed to the ring yoke 3. Thus, the diaphragm 6 is supported in a state in
which the other portions except the bonding surface 33 are floating from the ring yoke 3 and the
pole piece 4. Also, the voice coil 7 mechanically and tightly coupled to the diaphragm 6 is located
in the gap 5 as described above, and the poles forming the inner peripheral surface of the ring
yoke 3 and the gap 5 constituting the gap 5 It is supported so as not to contact the outer
peripheral surface of the piece 4.
[0019]
As the adhesive 66, an adhesive having elasticity even after curing is selected and used. As an
example of a resilient adhesive even after curing, there is a one-component RTV rubber KE347
13-05-2019
7
manufactured by Shin-Etsu Chemical Co., Ltd., which was used in the examples of the present
invention.
[0020]
When a sound wave reaches the microphone, the diaphragm 6 vibrates according to the sound
wave, and the voice coil 7 vibrates integrally with the diaphragm 6. The voice coil 7 breaks the
magnetic flux in the gap 5 by the vibration of the voice coil 7, and an electric signal according to
the sound wave is generated in the voice coil 7. Thus, the sound wave is converted into an
electrical signal and output from the microphone. The voice coil 7 and the magnetic circuit
constitute a conversion unit which electrically acts on the vibrating plate 6 which receives and
vibrates the sound wave and converts the vibration into an electric signal.
[0021]
In the embodiment shown in FIG. 1, the cover 8 functioning as an equalizer is fitted at the tip of
the peripheral wall 31 of the ring yoke 3. The cover 8 covers the diaphragm 6 and maintains a
gap with the diaphragm 6. The cover 8 is formed with an appropriate number of holes 81 for
introducing the sound wave into the diaphragm 6. The portion described above is exactly the
microphone unit, and the microphone unit is mounted on the microphone case, and the other
parts are attached to the microphone case, wiring with the connector, and the like are performed
to complete the microphone.
[0022]
According to the embodiment described above, in the diaphragm 6, the adhesive portion 64 of
the outer peripheral edge is in line contact with the adhesive surface 33 of the ring yoke 3 as a
support, and the line contact portion is Since it is fixed to the ring yoke 3, the width f of the
bonding portion 64 can be narrowed as compared with the conventional example in which the
surface is in contact with the support. Since the dimension g in the radial direction of the sub
dome portion 62 of the diaphragm 6 can be increased to widen the area, the diaphragm 6
becomes easy to move when a sound wave is received, and a dynamic microphone with a small
diameter is obtained. Even in this case, there is an advantage that the frequency response up to
the low range can be secured and the sound can be easily collected up to the low range. In
addition, since the width f of the bonding portion 64 can be narrowed, the area of the center
13-05-2019
8
dome portion 61 can be sufficiently taken, and the sensitivity can be secured even if the dynamic
microphone has a small diameter. it can.
[0023]
In addition to the above effects, the adhesive 66 separates from the bonding surface 33 and the
inner peripheral surface of the peripheral wall 31 of the ring yoke 3 except for the outer
peripheral edge of the diaphragm 6 in line contact with the bonding surface 33 Since the
adhesive 66 penetrates and hardens in the separated parts to fix the diaphragm 6, the adhesive
66 does not stick out to parts other than the bonding surface 33, and the movable plate of the
diaphragm 6 can be effectively moved by the hardening of the adhesive. It is possible to solve the
problem that parts are limited. This can increase the frequency response and sensitivity up to the
low band.
[0024]
The adhesive 66 is an elastic adhesive even after curing, so that the diaphragm 6 becomes easy
to move even after the adhesive 66 is cured, from this point as well, the frequency response to
the low region and the frequency response The sensitivity can be increased.
[0025]
It is a longitudinal cross-sectional view which shows the Example of the dynamic microphone
concerning this invention.
It is a longitudinal cross-sectional view which shows the example of the conventional dynamic
microphone.
Explanation of sign
[0026]
Reference Signs List 1 magnet 2 yoke 3 ring yoke 4 pole piece 5 gap 6 diaphragm 7 voice coil 33
adhesive surface 61 center dome portion 62 sub dome portion 64 adhesive portion 66 adhesive
13-05-2019
9
13-05-2019
10
Документ
Категория
Без категории
Просмотров
0
Размер файла
20 Кб
Теги
jp2006197070
1/--страниц
Пожаловаться на содержимое документа