close

Вход

Забыли?

вход по аккаунту

?

JPH118898

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 JPH118898
[0001]
TECHNICAL FIELD The present invention relates to a speaker device.
[0002]
2. Description of the Related Art Conventionally, as a speaker apparatus, one configured as
shown in FIG. 5 is used. The speaker device 51 shown in FIG. 5 includes a vibration system 70
that generates sound, a magnetic circuit unit 60 that drives the vibration system 70, and a frame
52 that supports the vibration system 70.
[0003]
The magnetic circuit unit 60 has a yoke 61 made of a magnetic material. The yoke 61 has a
cylindrical center pole 63 protruding from a central portion of a flat plate portion 62 formed in a
disk shape, and is disposed on the back side of the speaker device 51.
[0004]
A magnet 64 for applying a magnetic flux to the yoke 61 is disposed on the yoke 61. The magnet
01-05-2019
1
64 is formed in an annular shape having a central hole 64a, and the center pole 63 is inserted
into the central hole 64a. In the magnetic circuit unit 60, a space area is formed between the
center hole 64 a of the magnet 64 and the outer peripheral surface of the center pole 63.
[0005]
A top plate 66 made of a magnetic material is disposed on the magnet 64. The top plate 66 is
formed in an annular shape having a center hole 66a, and the center pole 63 is inserted through
the center hole 66a. A magnetic gap G is formed between the peripheral wall of the center hole
66 a of the top plate 66 and the outer peripheral surface of the center pole 63.
[0006]
A frame 52 supporting the vibration system 70 is mounted on the top plate 66. The frame 52 is
formed of a metal material in a substantially cylindrical shape whose diameter increases from the
rear end side toward the front end side.
[0007]
The vibration system 70 supported by the frame 52 has a diaphragm 71. The diaphragm 71 is
formed in a substantially conical shape, and a mounting hole 71a is formed in the central
portion. An edge 72 is attached to the outer peripheral portion of the diaphragm 71, and the
edge 72 is fixed to a holding portion 54 formed on the front end side of the frame 52 through an
annular gasket 53. Also, a dome-shaped cap 73 is attached to the diaphragm 71 so as to close
the attachment hole 71a.
[0008]
A voice coil bobbin 74 is attached to the attachment hole 71 a of the diaphragm 71. The voice
coil bobbin 74 is formed in a cylindrical shape, and a voice coil 75 is wound on the proximal end
side. Both ends of the voice coil 75 are electrically connected to connection portions 56 provided
on the outer peripheral portion of the frame 52 through the tinsel wires 55. The voice coil
bobbin 74 is connected to the mounting hole 71 a of the diaphragm 71 in the state where the
01-05-2019
2
voice coil 75 is inserted into the magnetic gap of the magnetic circuit unit 60.
[0009]
Between the voice coil bobbin 74 and the frame 52, a damper 76 is disposed which supports the
voice coil bobbin 74 so as to be linearly movable from the front side to the back side of the
speaker device 51. The damper 76 has a central hole, and a large number of annular uneven
portions are concentrically formed from the central hole to the outer peripheral portion. The
damper 76 is displaceable by the uneven portion, and the voice coil bobbin 74 is supported in a
linearly movable manner by inserting the voice coil bobbin 74 into the central hole.
[0010]
In the speaker device 51 configured as described above, when a current is supplied to the voice
coil 74 inserted into the magnetic gap G, an electromagnetic force acts on the voice coil 76, and
the voice coil bobbin 75 is in the magnetic gap G. Move up and down. Then, with the movement
of the voice coil bobbin 75, the diaphragm 71 vibrates.
[0011]
By the way, in the speaker device 51 of this type, it is desirable to have a small size and good low
frequency characteristics. However, when the speaker device 51 is miniaturized, the magnetic
circuit unit 60 is also miniaturized so that it is difficult to generate a large driving force, and the
resonance sharpness Q0 at the lowest resonance frequency f0 becomes large and the frequency
characteristic of the low frequency region Getting worse. Therefore, in order to improve the
frequency characteristic of the low band, the speaker device 51 needs to limit the high sensitivity
vibration of the vibration system 70 to lower the resonance sharpness Q0 at the lowest
resonance frequency f0.
[0012]
In order to limit the sensitive vibration of the vibration system 70, it is conceivable to increase
the mass of the diaphragm 71 and the voice coil bobbin 74. However, when the actual mass of
01-05-2019
3
the diaphragm 71 and the voice coil bobbin 74 is increased, it is necessary to reduce the
compliance of the damper 76 and the edge 72 in order to support these correctly, and the
resonance sharpness Q0 is increased.
[0013]
Therefore, according to the present invention, the sensitivity of the vibration system is limited
without increasing the mass of the diaphragm or voice coil bobbin, and the resonance sharpness
Q0 at the lowest resonance frequency f0 is lowered to obtain good low frequency characteristics.
It is an object of the present invention to provide a speaker device that is designed to
[0014]
SUMMARY OF THE INVENTION In order to achieve the above object, the loudspeaker device
according to the present invention forms an airtight space by at least a damper and a magnetic
circuit portion, and the magnetic circuit portion communicates the inside and the outside of the
airtight space. Provide a means for
[0015]
In the speaker device, the flow of air into and out of the airtight space is performed by the
communication means provided in the magnetic circuit unit, so the flow rate of air to the airtight
space is limited.
Therefore, when the vibration system vibrates, the speaker device generates a load due to the
internal pressure fluctuation in the airtight space, and the load limits the sensitive vibration of
the vibration system.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be
described below with reference to the drawings.
[0017]
As shown in FIG. 1, the speaker device 1 includes a vibration system 20, a magnetic circuit unit
10 for driving the vibration system 20, and a frame 2 for supporting the vibration system 20.
01-05-2019
4
[0018]
The magnetic circuit unit 10 is disposed on the back side of the speaker device 1 and includes a
yoke 11 formed of a magnetic material.
The yoke 11 has a cylindrical center pole 13 protruding from a central portion of a flat plate
portion 12 formed in a disk shape.
[0019]
A magnet 14 is disposed on the yoke 11.
The magnet 14 is formed in an annular shape having a central hole 14a.
The diameter of the center hole 14 a of the magnet 14 is larger than the diameter of the center
pole 13, and the center pole 13 of the yoke 11 is inserted into the center hole 14 a of the magnet
14. A stepped portion 12a is formed annularly at the central portion of the flat plate portion 12
of the yoke 11 so as to surround the outer periphery on the base end side of the center pole 13.
Is fitted to position the magnet 14. A space area is formed between the peripheral wall of the
center hole 14 a of the magnet 14 and the outer periphery of the center pole 13 of the yoke 11.
[0020]
A top plate 15 which constitutes a magnetic gap G between the magnet 14 and the center pole
13 of the yoke 11 is disposed on the magnet 14. The top plate 15 is formed of a magnetic
material in an annular shape having a central hole 15a. The diameter of the center hole 15a of
the top plate 15 is slightly larger than the diameter of the center pole 13, and the center pole 13
of the yoke 11 is inserted into the center hole 15a of the top plate 15. A magnetic gap G is
formed between the peripheral wall of the center hole 15 a of the top plate 15 and the outer
peripheral surface of the center pole 13.
01-05-2019
5
[0021]
A frame 2 supporting the vibration system 20 is attached on the top plate 15 by screwing or the
like. The frame 2 is formed of a metal material in a substantially cylindrical shape whose
diameter is increased from the base end side toward the front end side.
[0022]
The vibration system 20 supported by the frame 2 is provided with a substantially conical
diaphragm 21. The diaphragm 21 is disposed on the front side of the speaker device 1, and a
mounting hole 21a is formed in the center. The front side opening of the mounting hole 21a is
closed by a dome-shaped cap 22 so that dust and the like from the front side of the diaphragm
21 are prevented from entering. Further, the diaphragm 21 is configured such that deformation
in the radial direction is prevented by closing the mounting hole 21 a by the cap 22.
[0023]
A flexible toroidal edge 28 is attached to the front side outer periphery of the diaphragm 21, and
its outer peripheral end is formed on the front side outer periphery of the frame 2 through the
annular gasket 5 It is fixed to the holding portion 6. The edge 28 connects the diaphragm 21 to
the frame 2 and supports the diaphragm 21 to vibrate linearly from the front side to the rear side
of the speaker device.
[0024]
A voice coil bobbin 24 on which a voice coil 23 is wound around an outer peripheral surface is
attached to the back side of the diaphragm 21. The voice coil bobbin 24 is formed in a cylindrical
shape whose inner diameter is slightly larger than the outer diameter of the center pole 13 of the
yoke 11, and the base end portion projects from the diaphragm 21 toward the back side of the
speaker device 1. Thus, the tip end side is connected to the mounting hole 21 a of the diaphragm
21. The voice coil 23 is wound around the outer peripheral surface of the voice coil bobbin 24 on
the base end side. Both ends of the voice coil 23 are electrically connected via soldered wires 3 to
connection portions 4 provided on the outer peripheral portion of the frame 2 and to which
external signals are input.
01-05-2019
6
[0025]
Further, the voice coil bobbin 24 is disposed on the outer peripheral side of the center pole 13 of
the yoke 11 so that the voice coil 23 is positioned in the magnetic gap G.
[0026]
The voice coil bobbin 24 is movably supported from the front side to the back side of the speaker
device 1 by a damper 26 disposed between the voice coil bobbin 24 and the frame 2.
[0027]
The damper 26 has a sealed structure by coating a base formed of a cloth or the like with a
foamed resin such as acryl or rubber, or impregnating a base such as a cloth with a phenolic
resin or the like, thereby blocking air flow. It is done like that.
Further, the damper 26 may be formed of a polyester film or the like which does not allow air to
pass therethrough, and the air flow may be shut off.
Then, the voice coil bobbin 24 is inserted into the center hole of the damper 26 and the outer
peripheral end is attached to the frame 2 to support the voice coil bobbin 24 and to provide a
space region between the above-described magnetic circuit unit 10 and Form. This space area
communicates with the space area in the magnetic circuit unit 10 described above, and is
configured as an airtight space 27 that applies a load to the movement of the vibration system
20.
[0028]
The damper 26 is a so-called corrugation damper, and a large number of annular irregularities
are formed concentrically from the central hole to the outer peripheral portion. The damper 26
movably supports the voice coil bobbin 24 by inserting the voice coil bobbin 24 into the center
hole. The damper 26 allows a large displacement easily by forming an annular uneven portion
concentrically, and when the voice coil bobbin 24 is driven, the voice coil bobbin 24 is viewed
from the front side of the speaker device 1 from the back side. It supports linearly movable to the
01-05-2019
7
side.
[0029]
By the way, in the magnetic circuit unit 10 described above, a flow passage 17 is formed which
communicates the inside and the outside of the airtight space 27 formed from the damper 26 to
the magnetic circuit unit 10. Then, air flows into and out of the airtight space 27 through the
flow path 17.
[0030]
For example, as shown in FIG. 2, the flow path 17 is configured as a narrow slit formed from the
center hole 15 a of the top plate 15 to the outer peripheral portion.
[0031]
As described above, the speaker device 1 restricts the flow rate of air to the airtight space 27 by
forming the flow path 17 with a narrow slit.
Therefore, when the vibration system 20 vibrates, the speaker device generates a load due to the
internal pressure fluctuation of the hermetic space 27. This load limits the sensitive vibration of
the vibration system 20.
[0032]
That is, when a drive current is supplied to the voice coil 23 and the voice coil bobbin 24 moves
to the back side of the speaker device 1, the damper 26 is displaced, and the airtight space 27 is
compressed. At this time, the air in the airtight space 27 flows out through the flow path 17 as
shown by the arrow A in FIG. 1, but the flow path 17 is constituted by a narrow slit, Since the
flow rate is limited, the internal pressure of the airtight space 27 temporarily rises. Due to the
increase in internal pressure of the airtight space 27, a load is applied to the movement of the
voice coil bobbin 24 to the back side.
01-05-2019
8
[0033]
On the other hand, when the voice coil bobbin 24 moves to the front side of the speaker device 1,
the damper 26 is displaced accordingly, and the airtight space 27 is expanded. At this time, the
external air flows into the airtight space 27 through the flow path 17 as shown by the arrow B in
FIG. 1, but the flow path 17 is configured by a narrow slit, Since the flow rate is limited, the
internal pressure of the airtight space 27 temporarily decreases. Due to the decrease in internal
pressure of the airtight space 27, a load is applied to the movement of the voice coil bobbin 24 to
the front side.
[0034]
As described above, when the voice coil bobbin 24 moves, the speaker device 1 is subjected to a
load due to the internal pressure fluctuation of the airtight space 27, thereby limiting the
sensitive vibration of the vibration system 20, and the low frequency characteristic is good.
Become.
[0035]
Although the example in which the flow path 17 is configured by the narrow slit formed in the
top plate has been described above, the flow path 17 is not limited to the magnetic circuit unit
10 so as to limit the flow rate of air to the airtight space 27. For example, as shown in FIG. 3, the
through hole 18 may be provided in the flat plate portion 12 of the yoke 11 as the flow passage
17 as shown in FIG.
[0036]
In this case, a resonance member 28 may be attached to the bottom of the yoke 11 to resonate
with the air flowing out of the air-tight space 27 through the through hole 18.
Thus, the speaker device 1 attaches the resonance member 28 to the bottom surface side of the
yoke 11, and resonates the air flowing out from the airtight space 27 with the resonance member
28, thereby adding an acoustic additional mass in the low region. The low frequency
characteristics can be further improved.
[0037]
01-05-2019
9
Further, in the speaker device 1, in order to adjust the flow rate of air into and out of the airtight
space 27, as shown in FIG. 1, the damper 26 is provided with a through hole 26 a communicating
the inside and outside of the airtight space 27. It is also good.
By providing the through holes 26 a in the damper 26, the air can enter and leave the airtight
space 27 not only from the flow path 17 but also from the through holes 26 a of the damper 26.
[0038]
The speaker device 1 may deteriorate the acoustic characteristics if the load is too large when
the air enters and leaves the airtight space 27 only by the flow path 17. However, the damper 26
is provided with the through holes 26a. By performing the air flow into and out of the airtight
space 27 also from the through holes 26a, the flow rate of the air into and out of the airtight
space 27 can be adjusted, and the excessive load can be alleviated.
[0039]
Further, in the speaker device 1, in order to adjust the flow rate of air into and out of the airtight
space 27, as shown in FIG. 1, the cap 22 is provided with the through holes 22 a communicating
the inside and outside of the airtight space 27. Good.
By providing the through hole 22 a in the cap 22, the air can enter and leave the airtight space
27 not only from the flow path 17 but also from the through hole 22 a of the cap 22.
[0040]
The speaker device 1 adjusts the flow rate of the air into and out of the airtight space 27 by
carrying out the air in and out of the airtight space 27 from the cap 22 as in the case where the
through hole 26 a is provided in the damper 26. , Can relieve excess load.
[0041]
In the speaker device 1 configured as described above, when the drive current according to the
acoustic signal is supplied to the voice coil 23, the diaphragm 21 is vibrated by the action of the
drive current and the magnetic field of the magnetic circuit unit 10. , Sound reproduction is
01-05-2019
10
performed.
[0042]
Then, in the speaker device 1, an airtight space 27 is formed in a region surrounded by the
damper 26 and the magnetic circuit unit 10, and the air is made to flow into and out of the
airtight space 27 from a flow passage 17 such as a narrow slit. Thus, when the diaphragm 21
vibrates, the load due to the internal pressure fluctuation of the airtight space 27 is applied, the
sensitive vibration of the vibration system 20 is limited, and the frequency characteristic of the
low region becomes good.
[0043]
Further, in the speaker device according to the present invention, as shown in FIG. 4, the
auxiliary magnet 32 is provided on the back side of the yoke 11, and the shield cover 33 is
provided to cover the magnetic circuit unit 10, so that the magnetic flux of the magnet 14
becomes magnetic. The structure may be configured to prevent leakage to the outside of the
circuit unit 10.
[0044]
The speaker device 31 has the same configuration as the above-described speaker device 1
except that the auxiliary magnet 32 and the shield cover 33 are provided. Therefore, the same
components as the speaker device 1 are denoted by the same reference numerals. Detailed
explanation is omitted.
[0045]
Similar to the magnet 14, the auxiliary magnet 32 is formed in an annular shape having a central
hole 32 a and has substantially the same size as the magnet 14.
The auxiliary magnet 32 is disposed on the back side of the yoke 11 so as to face the magnet 14
with the yoke 11 interposed therebetween in a state in which the magnetic pole direction is
opposite to the magnetic pole direction of the magnet 14. There is.
[0046]
01-05-2019
11
The shield cover 33 is formed by raising a peripheral wall 33b from the outer peripheral portion
of the bottom plate 33a.
A bottom plate 33a of the shield cover 33 is attached to the back side of the auxiliary magnet 32,
and a peripheral wall 33b is disposed on the outer peripheral side of the magnetic circuit portion
10 so as to cover the magnetic circuit portion 10.
At a central portion of the bottom plate 33b of the shield cover 33, a projecting portion 34
having substantially the same diameter as the central hole 32a of the auxiliary magnet 32 is
formed.
Then, the projection 34 is engaged with the center hole 32 a of the auxiliary magnet 32 from the
rear side, whereby the shield cover 33 is attached to the rear side of the auxiliary magnet 32.
[0047]
In the speaker device 31, the magnetic flux leaking to the outside is canceled by the magnetic
flux of the auxiliary magnet 32, so the leakage of the magnetic flux to the outside is prevented,
and the magnetic flux density passing through the magnetic gap G is improved.
Further, in the speaker device 31, since the magnetic circuit unit 10 is covered by the shield
cover 33, leakage of the magnetic flux to the outside is further prevented.
[0048]
Further, the above-described embodiment is an example in which the present invention is applied
to the speaker device 1 or 31 provided with the so-called external magnetic type magnetic circuit
unit 10 in which the annular magnet 14 is disposed on the outer peripheral side of the center
pole 13 of the yoke 11. However, the present invention is not limited to this example, and as
shown in FIG. 5, a so-called internal magnet in which a cylindrical magnet 44 is disposed in a
bottomed cylindrical cage yoke 43 is provided. The present invention can also be applied to a
speaker device 41 provided with a magnetic circuit unit 42 of a type.
01-05-2019
12
[0049]
The speaker device 41 has the same configuration as the above-described speaker device 1
except that the magnetic circuit unit 42 is an internal magnet type, and thus the above-described
speaker device 1 has the same configuration as the speaker device 1. The detailed description is
omitted using the same reference numerals as in FIG.
[0050]
The magnetic circuit unit 42 of the speaker device 41 includes a yoke 43 formed in a bottomed
cylindrical shape of a magnetic material.
A magnet 44 formed in a cylindrical shape is disposed on the bottom plate 43 a of the yoke 43
so that the peripheral wall 43 b protrudes from the central portion of the bottom plate 43 a of
the yoke 43 in the rising direction.
The upper surface of the magnet 44 has substantially the same height as the upper end of the
peripheral wall 43 b of the yoke 43.
[0051]
On the magnet 44, a pole piece 45 formed in a flat plate shape of a magnetic material is
provided. The pole piece 45 has a disk shape having substantially the same diameter as the
magnet 44.
[0052]
Further, a plate 46 which forms a magnetic gap G with the pole piece 45 is provided at the upper
end portion of the peripheral wall 43 b of the yoke 43. The plate 46 is formed of a magnetic
material in an annular shape having a central hole 46a. The plate 46 has a thickness
substantially the same as the thickness of the pole piece 45, and the diameter of the central hole
46a is slightly larger than the diameter of the pole piece 45. The plate 46 is provided on the
upper end portion of the peripheral wall 43 b of the yoke 43 so that the pole piece 45 provided
on the magnet 44 is inserted into the central hole 46 a, so that the plate 46 is magnetically
01-05-2019
13
coupled to the pole piece 45. The gap G is configured.
[0053]
The frame 2 is attached on the plate 46 by screwing or the like, and the vibration system 20 is
supported by the frame 2.
[0054]
Like the vibration system 20 of the speaker device 1 described above, the vibration system 20 of
the speaker device 41 also includes the damper 26 whose air flow from the surface is blocked.
In the speaker device 41, the air flow from the surface of the damper 26 is shut off to form an
airtight space 27 which applies a load to the movement of the vibration system 20 in a region
surrounded by the damper 26 and the magnetic circuit unit 42. .
[0055]
Further, in the magnetic circuit unit 42 described above, a flow path 17 communicating the
inside and the outside of the airtight space 27 formed in the area surrounded by the damper 26
and the magnetic circuit unit 42 is formed. The flow path 17 is constituted of, for example, a
small diameter ventilation pipe 47 provided from the plate 46 to the bottom plate 43 a of the
yoke 43.
[0056]
One end of the ventilation tube 47 is embedded in the plate 46 and the end of the frame 2
mounted on the plate 46 and opened at the damper 26 side, and the other end is embedded in
the bottom plate 46 a of the yoke 46 to form a magnetic circuit It is disposed in the area
surrounded by the peripheral wall 43 b of the yoke 43 in a state of being opened on the back
side of the reference numeral 42. Then, the air flows into and out of the airtight space 27
through the vent pipe 47.
01-05-2019
14
[0057]
In the speaker device 41, the flow of air into and out of the hermetic space 27 is restricted by the
fact that the air flows into and out of the hermetic space 27 through the small-diameter vent pipe
47. Therefore, in the speaker device 41, when the vibration system 20 vibrates, a load is
generated due to the internal pressure fluctuation of the airtight space 27, and the sensitive
vibration of the vibration system 20 is limited by the load.
[0058]
In the speaker device 41 configured as described above, when the drive current according to the
acoustic signal is supplied to the voice coil 23, the diaphragm 21 is vibrated by the action of the
drive current and the magnetic field of the magnetic circuit unit 42. , Sound reproduction is
performed.
[0059]
Then, in the speaker device 41, an airtight space 27 is formed in a region surrounded by the
damper 26 and the magnetic circuit portion 42, and the air flows into and out of the airtight
space 27 from the flow passage 17 such as the small diameter ventilation tube 47. Since this is
performed, when the diaphragm 21 vibrates, a load due to the internal pressure fluctuation of
the airtight space 27 is applied, the sensitive vibration of the vibration system 20 is limited, and
the frequency characteristic of the low region becomes good.
[0060]
As described above, in the speaker device according to the present invention, the airtight space is
formed in the region surrounded by the damper and the magnetic circuit portion, and the means
for connecting the inside and the outside of the airtight space is the magnetic circuit. Because the
vibration system vibrates, the load is applied to the vibration system due to the internal pressure
fluctuation of the airtight space, so that the sensitive vibration of the vibration system is limited,
and good frequency characteristics in the low frequency range are obtained. Can.
[0061]
Brief description of the drawings
[0062]
1 is a longitudinal sectional view showing a speaker device according to the present invention.
01-05-2019
15
[0063]
2 is a perspective view of the top plate.
[0064]
3 is a longitudinal sectional view showing another speaker device according to the present
invention.
[0065]
4 is a longitudinal sectional view showing another speaker device according to the present
invention.
[0066]
5 is a longitudinal sectional view showing still another speaker device according to the present
invention.
[0067]
6 is a longitudinal sectional view showing a conventional speaker device.
[0068]
Explanation of sign
[0069]
1, 31, 41 speaker device, 2 frame, 10, 42 magnetic circuit unit, 11, 43 yoke, 14, 44 magnet, 17
flow path, 18 through hole, 21 diaphragm, 23 voice coil, 24 voice coil bobbin, 26 damper , 27
airtight space, 47 vent pipe
01-05-2019
16
Документ
Категория
Без категории
Просмотров
0
Размер файла
26 Кб
Теги
jph118898
1/--страниц
Пожаловаться на содержимое документа