close

Вход

Забыли?

вход по аккаунту

?

DESCRIPTION JP2000197188

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 JP2000197188
[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a
small-sized speaker, and more particularly to a small-sized speaker in which the sound radiation
force is added according to the direction of movement of a diaphragm to make bass sound
stronger.
[0002]
2. Description of the Related Art Conventionally, various structures have been proposed as smallsized speakers, but FIG. 7 shows a side cross-sectional view of the most common small-sized
speaker. The speaker 20 shown in FIG. 7 is formed of a disk-shaped plate material, and integrally
integrates a columnar center pole 4a embedded in the center and a magnet guide portion 4b
concentrically formed with a stepped portion so as to surround the center pole 4a. A yoke 4
having an inverted T-shaped cross section, a ring-shaped magnet 3 which is fitted in an inner
diameter to the magnet guide portion 4b of the yoke 4 and which is magnetized in the thickness
direction, and A magnetic circuit of a metal part is constituted by a ring-shaped plate 1 joined to
the upper surface with an adhesive or the like and a funnel-shaped frame 7 made of steel or the
like fixed on the plate 1.
[0003]
A state in which a spacer such as kraft paper is wound around the inner periphery of the voice
coil bobbin 8 in order to insert the voice coil 8a wound around the voice coil bobbin 8 in the
12-04-2019
1
concentric magnetic gap 17 between the center pole 4a and the plate 1 Then, the voice coil
bobbin 8 is inserted into the center pole 4 a from the upper side, and the position of the voice
coil 8 a is set so as to be disposed in the magnetic gap 17.
[0004]
A wave-shaped concentric damper 9 is bonded between the outer diameter of the upper end of
voice coil bobbin 8 and the outer periphery of the bottom of frame 7 with an adhesive or the like,
and a cone-shaped diaphragm with funnel-shaped fixed edge 13 The inner diameter portion 10 is
fitted and joined to the outer diameter of the upper end portion of the voice coil bobbin 8, and
the largest diameter portion of the diaphragm 10 is joined to the largest diameter opening
portion of the frame 7 via a gasket 12.
[0005]
Further, after drying the adhesive, remove the spacer inserted into the inner diameter of the
voice coil bobbin 8 so that the dust preventing cap 14 covers the inner surface of the diaphragm
10 on the upper surface of the voice coil bobbin 8 or the inclined portion of the diaphragm 10
Join.
[0006]
The lead wire from the voice coil 8a is connected to the input terminal 15 via the tinsel wire 16,
and an acoustic signal is supplied to the voice coil 8a via the input terminal 15.
Although the case where the magnet 3 magnetized in advance is assembled has been described
above, the magnet 3 which is not magnetized may be magnetized in the final assembly stage.
[0007]
SUMMARY OF THE INVENTION In the above-described small-sized speaker described as the
conventional configuration, the speaker box is also small and light, and when the diaphragm 10
of the small-sized speaker 20 is driven in FIG. When the radiation force F acts forward (upward
in FIG. 7), the reaction force -F acts rearward (downward in FIG. 7) and the lightweight speaker
box swings backward.
12-04-2019
2
Since the speaker box moves backward in this manner, the sound radiation force from the
diaphragm 10 is reduced, and the driving force corresponding to the driving power supplied to
the voice coil 8a becomes smaller and the problem that the bass can not radiate strongly arises. .
[0008]
As described above, in order to support the sound radiation force F of the speaker 20 built in the
small and light speaker box so that the speaker box does not swing, it is necessary to set the
following condition (1).
F = (F + m) R (1) where m is the weight including the speaker and the speaker box, R is the
frictional resistance between the speaker box and the mounting surface.
[0009]
Assuming that the sound radiation force F of the speaker 20 is not supported by the speaker box,
the loss of the sound radiation force of the diaphragm 10 is Floss, and the actual sound radiation
force of the diaphragm 10 is Fc, Floss = F− (F + m) R .. (2). Therefore, if Fc = F-Floss, then Fc = FF- (F + m) RFc = (F + m) R .. (3). Therefore, the actual sound radiation force Fc of the diaphragm
10 of the speaker 20 will be the supporting force of the speaker box. Supporting such a reaction
force is extremely difficult in a small and light speaker box, and the sound radiation power in the
low frequency range is disadvantageously reduced.
[0010]
The present invention is intended to obtain a speaker that solves the problems of overhead, and
the problem to be solved by the present invention is that even a small speaker is strong by
providing a second diaphragm that works in the same direction as the diaphragm. It is an object
of the present invention to provide a speaker capable of sound emission and capable of
reproducing bass well.
[0011]
A speaker 20 according to the present invention comprises a cap 14 for covering an inner
diameter portion of a first diaphragm 10 to maintain airtightness of a space portion behind the
12-04-2019
3
inner diameter portion, and a center pole constituting a magnetic circuit. A first diaphragm 4 is
provided with a through hole 4c bored in 4a and a second diaphragm 2 movably pivoted to the
rear of the magnetic circuit while maintaining airtightness. The air pressure in the space
including the through hole 4c on the rear side of the cap 14 of the diaphragm 10 is changed so
that the driving direction of the second diaphragm 2 is added to the driving direction of the first
diaphragm 10 It is.
[0012]
According to the speaker 20 of the present invention, the second diaphragm 2 is also moved in
the same direction in response to the movement of the first diaphragm 10, so that the first
driving force is greater than the electric driving force supplied to the voice coil. The diaphragm
can be driven, and even with a small speaker, a speaker capable of strong bass emission can be
obtained.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION A loudspeaker and a loudspeaker apparatus
according to the present invention will be described below with reference to FIGS.
FIG. 1 is a side sectional view showing an embodiment of the speaker according to the present
invention. In FIGS. 1 to 6, the parts corresponding to those of FIG.
[0014]
In FIG. 1, since the configurations of the vibration system and the magnetic circuit are
substantially the same as those of FIG. 7, only different configurations in the magnetic circuit will
be described below.
[0015]
In this embodiment, a through hole 4c penetrating from the top to the bottom is formed at the
center of a center pole 4a erected substantially at the center of the yoke 4.
Furthermore, a cylindrical synthetic resin casing 5 with a bottom is fixed so as to surround the
12-04-2019
4
yoke 4, the magnet 3 and the outer periphery of the plate 1 constituting the magnetic circuit, and
is opposed to the through hole 4c drilled at the center of the center pole 4a. The through hole 5a
is formed in the bottom of the casing 5 at the position shown in FIG.
[0016]
Further, the second diaphragm 2 having a predetermined compliance and mass is pivotally
pivotally attached to the bottom of the casing 5 so as to face the through hole 5a.
The shape of the second diaphragm 2 can be selected as appropriate, but in the present example,
a cap in which the second diaphragm 2 formed of an edge having a substantially W-shaped cross
section and the diaphragm is joined onto the voice coil bobbin 8 Together with 14, it is
constructed to keep airtightness and is pivotally attached.
Further, the dampers 9 and the like do not need to be particularly airtight, and may be waveshaped dampers made of breathable ordinary paper or the like.
[0017]
In the speaker 20 having the above configuration, a through hole is formed in the inside
diameter of the voice coil bobbin 8 covered by the outer periphery of the center pole 4a and the
second space 17b surrounded by the inside diameter of the magnet 3 and the cap 14 and in the
center pole 4a. The pressure difference between the first space 17a in the second diaphragm 2
communicated through 4c is substantially isolated by the extremely small magnetic gap 17
between the inner diameter of the voice coil bobbin 8 and the outer diameter of the center pole
4a. Driving the first diaphragm 10 by moving the second diaphragm 2 in the same direction so as
to move in the same direction as the first diaphragm 10. It is intended to make the amount of
movement of
[0018]
The operation of this speaker is the same as that of the speaker 20 of the other embodiment
shown in FIGS. 2 to 4 and therefore will be described later. The difference in configuration
between the speaker 20 of FIGS. 2 to 4 and that of FIG.
[0019]
12-04-2019
5
The difference from FIG. 1 of FIG. 2 is that the concentric cancellation magnet 6 is bonded to the
bottom surface of the yoke 4 via an adhesive or the like in order to make the speaker 20 of the
magnetic shielding type.
The polarity in the thickness direction of the cancel magnet 6 is reverse to that of the magnet 3.
Furthermore, the bottomed cylindrical casing 5 surrounding the magnetic circuit including the
cancel magnet 6 and the magnet 3 and the like of the magnetic circuit similar to FIG. 1 is made
metallic and the N pole of the bottom of the cancel magnet 6 and the plate 1 The configuration is
the same as that of FIG. 1 except that a magnetic flux passing between the N poles of the
magnetic flux path is formed so as not to generate a leakage magnetic flux.
[0020]
Accordingly, in the speaker 20 of the configuration of FIG. 2, the air volume of the first space
portion 17a is increased as compared to the speaker 20 of the configuration of FIG. 1 only in the
space portion surrounded by the bottom surface of the yoke 4 and the inner diameter of the
cancel magnet 6. .
[0021]
The embodiment shown in FIG. 3 has the same configuration as that of FIG. 2 except that the
same configuration as that of FIG.
[0022]
The second diaphragm 2 of the speaker 20 shown in FIG. 3 is opposed to the through hole 5a
formed at the center of the bottom of the casing 5, and the second diaphragm 2 is formed of the
damper 2a and the flat diaphragm 2b. They are pivotally mounted on a cylindrical holder 11
joined to the bottom of the housing 5. These configurations, including the holder 11 and the
second diaphragm 2, are also maintained so as to maintain airtightness. There is.
[0023]
In the embodiment shown in FIG. 4, the speaker 20 is a magnetically shielded speaker as in FIG.
3, and the disk is flat against the open end of the cylindrical holder 11 having substantially the
same diameter as the casing 5 in order to enlarge the second diaphragm 2. The second
12-04-2019
6
diaphragm 2 in which the dome-shaped concentric circular edge 2a is joined to the outer
periphery of the second diaphragm 2b is movably pivoted up and down. A cylindrical airtight
braking damper 19 is interposed below the through hole 5a while the hole 11a is bored and the
through hole 5a is enclosed, and the upper and lower sides of the airtight control damper 19 are
the bottom of the casing 5 and the diaphragm It is bonded to the upper surface of 2b, and as the
airtight control damper 19, a crystalline foamed synthetic resin or the like may be used.
[0024]
The operation of the speaker 20 having the configuration described in detail in FIGS. 1 to 4 will
be described simultaneously with reference to FIGS. 1 to 4.
[0025]
Now, in the speaker 20 of FIG. 1 to FIG. 4, it is assumed that the voice coil 8a is supplied with a
predetermined power to drive the first diaphragm 10 and move forward by the sound radiation
force indicated by F. The volume in the space of the first space 17a in the coil bobbin 8 is
increased.
[0026]
Therefore, the pressure of the air in the first space 17a decreases, and the pressure in the first
space 17a becomes the second space 17b as shown by the flow of air shown by the arrow A in
FIGS. 1 to 4. The air flows into the first space 17a through the magnetic gap 17 between the
outer periphery of the center pole 4a and the voice coil bobbin 8 and is in a steady air pressure
(1 atm) state.
Accordingly, the volume in the through hole 4c communicating with the first space portion 17a
and the second diaphragm 2 is increased, and the pressure is reduced to draw the second
diaphragm 2 in the forward direction indicated by the arrow F1. For this purpose, the second
sound radiation force F1 is added to the first sound radiation force F, and the sound radiation
force in the particularly low range of the first diaphragm 10 supplies normal electrical energy to
the voice coil 8a. Compared to the case of
[0027]
12-04-2019
7
Similarly, when the first diaphragm 10 is driven rearward, the volume of air in the first space 17a
decreases, so the pressure in the first space 17a increases.
That is, the air in the first space portion 1a is a magnetic flow between the first space portion
17a → the outer periphery of the center pole 4a and the voice coil bobbin 8 as shown by the
flow of air shown by arrow B in FIGS. It flows into the second space 17b through the air gap 17
and is compressed by the steady air pressure.
Accordingly, the volumes of the through hole 4c and the second diaphragm 2 communicating
with the first space 17a decrease, and the pressure is increased, so that the second diaphragm 2
is in the direction opposite to the direction indicated by the arrow F1. The sound radiation force F1 in the opposite direction of the second sound radiation force F1 is added to the sound
radiation force -F in the opposite direction of the first sound radiation force F in order to be
pushed backward.
[0028]
Now, let the sound radiation force of the first diaphragm 10 be F, the mass of the first diaphragm
10 and the additional mass of air be M, and the acceleration of the first diaphragm 10 be α.
Assuming that the sound radiation force is F1, the mass of the second diaphragm 2 and the
additional mass of air are M1, and the acceleration of the second diaphragm 2 is α1, F = M · α ...
(4) F1 = M1 · α1. According to the loudspeaker of this example, the overall sound radiation force
F0 of the first diaphragm 10 is F0 = F + F1 = M · α + M1 · α1 where M = M1 and F0 = ( Thus, it
becomes possible to provide a speaker capable of increasing the sound radiation power of the
bass more than that of the normal energy application.
[0029]
5 and 6 show the case where the speaker 20 of the present invention is disposed in the phase
inversion type speaker box 21. In FIG. 5, a speaker sound emission hole in which the speaker 20
described in detail in FIG. The front surface of the first diaphragm 10 is fixed to be opposed to
the surface 23 in FIG.
[0030]
The speaker box 21 has a double structure of phase-reversal type ducts, and a small diameter
cylindrical first duct 24 extended into the speaker box 21 from a duct opening 24a drilled at the
lower end of the baffle board 22; A large-diameter cylindrical second duct 25 is extended from
the rear face plate 21B of the box 21 so that the second duct openings 25a overlap each other to
12-04-2019
8
the front side of the baffle board 22 and the direction orthogonal to the longitudinal direction By
making the cut surfaces concentric with each other, the sound radiation force FD from the duct
24 at the first duct opening 24a and the reaction force thereof-FD are the sound radiation force
FD1 from the second duct opening 25a. And, since the reaction force works to be mutually offset
by the FD 1, in the speaker device 27 of the present invention, in order to prevent the small and
lightweight speaker box 21 from swinging, the speaker device 27 That the sound radiation force
F0 = F + F1 it is sufficient to select the weight m and the frictional resistance R of the speaker
apparatus 27 described above so as to offset the reaction force -FD against.
[0031]
In FIG. 6, a third duct 26 is disposed opposite to the second diaphragm 2 so as to face the
through hole 5a formed in the bottom of the magnetic shield type speaker casing 5.
[0032]
In this case, assuming that the acceleration of air passing through the third duct 26 is αD and
the equivalent mass of the third duct 26 is MD, the radiation force FD2 of the third duct is FD2 =
MD · αD (7) The radiation force FD2 of this duct is also added corresponding to the driving
direction of the first diaphragm 10, and the moving amount of the diaphragm at the time of
driving the first diaphragm 10 can be increased.
[0033]
Further, as shown by the broken line in FIG. 6, the tip of the third duct 26 is extended to the
inner wall portion of the back surface plate 21B of the speaker box 21, and the through hole 28
is formed in the back surface plate 21B of the extended portion. The second diaphragm 2 may be
pivotably mounted so as to cover 28.
[0034]
According to the above configuration, the sound radiation force F1 generated by the second
diaphragm 2 and the duct sound radiation force FD2 in the third duct 26 are added to the sound
radiation force F of the first diaphragm to form F1 + FD2 + F1. Thus, the driving force is further
increased.
[0035]
According to the speaker and the speaker device of the present invention, the sound is
transmitted through the second diaphragm and the first space in the same direction as the
direction of the sound radiation force added to the sound radiation force of the first diaphragm.
12-04-2019
9
Since a force that increases the radiation force can be automatically generated by the speaker
itself, even a small speaker and a lightweight speaker device can emit bass strongly, and a large
driving power can be obtained compared to the driving energy. Have.
12-04-2019
10
Документ
Категория
Без категории
Просмотров
0
Размер файла
20 Кб
Теги
jp2000197188, description
1/--страниц
Пожаловаться на содержимое документа