close

Вход

Забыли?

вход по аккаунту

?

JP2010016603

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 JP2010016603
An object of the present invention is to make it difficult to generate discharge and to obtain a
large sound pressure. A conductive thin film layer 12 is not formed with a constant width from
an edge of a film 11 in a portion of a vibrating body 10 between a cushioning material 40U and a
cushioning material 40L. Since the edge portion of the conductive thin film layer 12 is not sharp
unless the conductive thin film layer 12 is formed on the edge portion of the film 11, a strong
electric field is not generated at the edge portion of the conductive thin film layer 12 and
discharge is less likely to occur. . Further, since discharge is difficult to occur, a high voltage is
applied to the electrodes 20U and 20L to increase the electrostatic force acting on the vibrator,
thereby increasing the displacement of the vibrator and obtaining a large sound pressure. be able
to. [Selected figure] Figure 3
Electrostatic speaker
[0001]
The present invention relates to an electrostatic speaker.
[0002]
The electrostatic speaker is composed of two parallel flat electrodes facing each other at intervals
and a sheet-like vibrating body having conductivity inserted between the two electrodes, and the
predetermined type of the vibrating body is When the bias voltage is applied and the voltage
applied to the electrodes is changed, the electrostatic force acting on the vibrating body is
changed, whereby the vibrating body is displaced.
04-05-2019
1
If this applied voltage is changed according to the acoustic signal to be input, the vibrator repeats
displacement (i.e. vibrates) accordingly, and an acoustic wave corresponding to the acoustic
signal is generated from the vibrator. Then, the generated acoustic wave is radiated to the
outside through the hole formed in the flat electrode.
[0003]
Then, as disclosed in Non-Patent Document 1, in the electrostatic speaker, ester wool is disposed
between the vibrator and the electrode, tension is not applied to the vibrator, and the edge
portion of the vibrator is not restrained. An electrostatic speaker of a structure has also been
devised. According to this configuration, the mode generated in the vibrator is improved as
compared with the case where the vibrator is under tension, and since the vibrator is not under
tension, the vibrator is vibrated largely. It is also possible to obtain a great sound pressure.
[0004]
M. Okazaki, 4 others, "Condenser speaker with diaphragm that vibrates in all bands and its
application", Proceedings of the 2004 Acoustical Society of Japan Annual Conference on
Acoustics, The Japan Acoustics Society, September 2004, p. 563-564
[0005]
By the way, the vibrating body of the electrostatic speaker has a thickness of several μm to
several tens μm and is very thin, and a conductive metal thin film layer is formed on both sides,
and the edge thereof The part is sharp and similar to the needle electrode.
If such a vibrator is placed between two electrodes without constraining the edge as described in
Non-Patent Document 1, a strong electric field is generated at the sharp edge, and the faces of
the electrodes Discharge is more likely to occur compared to the facing portion. In the
electrostatic speaker, it is necessary to apply a high voltage to the electrode in order to vibrate
the vibrating body, but if discharge is likely to occur, it becomes difficult to apply the high
voltage to the electrode. Then, if a high voltage is not applied to the electrodes, the electrostatic
force acting on the vibrator becomes weak, so the amount of displacement of the vibrator
becomes small, and a large sound pressure can not be obtained.
04-05-2019
2
[0006]
The present invention has been made under the above-described background, and it is an object
of the present invention to provide a technique capable of obtaining a large sound pressure with
less occurrence of discharge.
[0007]
In order to solve the problems described above, the present invention provides a first electrode
having conductivity, a second electrode having conductivity and spaced apart from the first
electrode, and an insulating base layer. And a conductive layer having conductivity provided on
the base material layer, and are disposed apart from the first electrode and the second electrode
between the first electrode and the second electrode. A first elastic member located between the
vibrating body and the first electrode and having insulating properties, elasticity and acoustic
transparency, and located between the vibrating body and the second electrode And a second
elastic member having an insulating property, elasticity, and acoustic transparency, in a portion
of the vibrator which can be displaced between the first electrode and the second electrode, the
base layer An electrostatic loudspeaker characterized in that the conductive layer is not provided
at least at a constant width from an edge To provide.
[0008]
In the present invention, the conductive layer may have a circular or elliptical shape.
Furthermore, in the present invention, the vibrator may not be tensioned.
[0009]
According to the present invention, a large sound pressure can be obtained because discharge is
unlikely to occur.
[0010]
Embodiment FIG. 1 is a view schematically showing the appearance of an electrostatic speaker 1
according to an embodiment of the present invention, and FIG. 2 is a schematic view showing a
04-05-2019
3
cross section and an electrical configuration of the electrostatic speaker 1. FIG. 3 is an exploded
perspective view of the electrostatic speaker 1.
As shown in the figure, this electrostatic speaker 1 has a vibrator 10, electrodes 20U and 20L,
spacers 30U and 30L, and cushion members 40U and 40L.
In the present embodiment, the configurations of the electrodes 20U and 20L are the same, and
the configurations of the spacers 30U and 30L are the same. Therefore, when there is no
particular need to distinguish between the respective members, "L" and "U The description of "is
omitted. Moreover, since the structures of both are the same also about cushion material 40U,
40L, when it is not necessary to distinguish both, description of "L" and "U" is abbreviate |
omitted. Also, the dimensions of each component in the figure are different from the actual
dimensions so that the shape of the component can be easily understood. Further, in the
drawings, those in which “•” is described in “o” means an arrow directed from the back to
the front of the drawing.
[0011]
(Configuration of Each Part of Electrostatic Speaker 1) First, each part of the electrostatic speaker
1 will be described. The vibrating body 10 is, for example, a conductive thin film layer 12 formed
by vapor deposition of a conductive metal or coating of a conductive paint on both sides of a
rectangular PET (polyethylene terephthalate) film 11. The thickness is about several micrometers
to several tens of micrometers. In the present embodiment, the conductive thin film layer 12 is
formed up to the edge portion on both sides of one of the four sides of the vibrating body 10, but
the conductive thin film layer has a constant width from the edge on both sides for the remaining
three sides. 12, the area of the conductive thin film layer 12 is smaller than the area of the film
11. In the vibrating body 10, the material of the film 11 is not limited to PET, and may be
synthetic resin other than PET, such as PP (polypropylene, polypropylene). Further, the width of
the region where the conductive thin film layer 12 is not provided in the vibrator 10 is not
limited to the width shown in FIG. 3 and can be set arbitrarily. Further, in the present
embodiment, the conductive thin film layer 12 is formed on both sides of the film 11, but the
conductive thin film layer 12 may be formed only on one side.
[0012]
04-05-2019
4
The spacer 30 is formed of an insulator, and its shape is a square frame as shown in FIG. The
cushioning material 40 is formed by applying heat and compression to cotton so that air can
pass therethrough, and its shape is rectangular. The cushioning material 40 has elasticity, and is
deformed when an external force is applied, and returns to its original shape when an externally
applied force is removed. The electrode 20 is formed of a conductive metal in a rectangular plate
shape. In the electrode 20, a plurality of through holes 21 penetrating from the front surface to
the back surface of the electrode 20 are provided at predetermined intervals in order to ensure
sound transmission.
[0013]
In the present embodiment, the lengths in the X direction and the Y direction of the spacer 30
and the lengths in the X direction and the Y direction of the electrode 20 are the same. Further,
the heights of the spacers 30U and the spacers 30L in the Z direction are the same. The length in
the X direction of the electrode 20 is longer than the length in the X direction of the vibrating
body 10, and the length in the Y direction of the vibrating body 10 is shorter than the distance in
the Y direction of the inner space of the spacer 30 There is.
[0014]
(Structure of Electrostatic Speaker 1) Next, the structure of the electrostatic speaker 1 will be
described. In the electrostatic loudspeaker 1, the electrode 20L is fixed to the lower surface of
the spacer 30L, and the electrode 20U is fixed to the upper surface of the spacer 30U. Further, in
the electrostatic speaker 1, the spacer 30U and the spacer 30L are fixed to each other between
the lower surface of the spacer 30U and the upper surface of the spacer 30L with one side of the
vibrating body 10 interposed therebetween. Here, what is sandwiched between the spacer 30U
and the spacer 30L in the vibrator 10 is a portion of the side where the conductive thin film layer
12 is formed up to the edge portion. And in the electrostatic type speaker 1, the cushioning
material 40L is arrange | positioned inside the frame-shaped spacer 30L, and the cushioning
material 40L is in contact with the vibrating body 10 and the electrode 20L. Further, a
cushioning material 40U is disposed inside the frame-shaped spacer 30U, and the cushioning
material 40U is in contact with the vibrating body 10 and the electrode 20U.
[0015]
In this embodiment, only one side of the vibrator 10 is sandwiched between the spacer 30U and
the spacer 30L, and the remaining three sides are not sandwiched between the spacer 30U and
04-05-2019
5
the spacer 30L, that is, tension is applied. In the state where the vibration member 10 is
positioned between the electrode 20U and the electrode 20L, but the cushioning material 40U
and the cushioning material 40L sandwich and support the vibrating body 10, the vibrating body
10 is not driven. Is located at an intermediate position between the electrode 20U and the
electrode 20L.
[0016]
(Electrical Configuration of Electrostatic Speaker 1) Next, the electrical configuration of the
electrostatic speaker 1 will be described.
As shown in FIG. 2, the electrostatic speaker 1 is a push-pull type including a transformer 50, an
input unit 60 to which an acoustic signal is input from the outside, and a bias power supply 70
for applying a DC bias to the vibrating body 10. It is an electrostatic speaker. The bias power
supply 70 is connected to the conductive thin film layer 12 formed on both sides of the film 11
and the middle point on the output side of the transformer 50, and the electrode 20U is
connected to one end on the output side of the transformer 50 An electrode 20L is connected to
the other end of the 50 output side. The input side of the transformer 50 is connected to the
input unit 60. In this configuration, when an acoustic signal is input to the input unit 60, a
voltage corresponding to the input acoustic signal is applied to the electrode 20.
[0017]
(Operation of Electrostatic Speaker 1) Next, the operation of the electrostatic speaker 1 will be
described. When an acoustic signal is input to the input unit 60, a voltage corresponding to the
input acoustic signal is applied to the electrode 20. Then, when a potential difference is
generated between the electrode 20U and the electrode 20L by the applied voltage, the vibrator
10 between the electrode 20U and the electrode 20L is drawn to either side of the electrode 20U
or the electrode 20L. Such electrostatic force works.
[0018]
For example, when an acoustic signal is input to the input unit 60, this acoustic signal is supplied
to the transformer 50, a positive voltage is applied to the electrode 20U, and a negative voltage is
applied to the electrode 20L. Since a positive voltage is applied to the thin film layer 12 by the
bias power supply 70, the vibrating body 10 repels the electrode 20U to which the positive
04-05-2019
6
voltage is applied, while the electrode 20L to which the negative voltage is applied. It is attracted
| sucked and displaced to the electrode 20L side (direction opposite to Z direction).
[0019]
In addition, when an acoustic signal is input to the input unit 60 and this acoustic signal is
supplied to the transformer 50 and a negative voltage is applied to the electrode 20U and a
positive voltage is applied to the electrode 20L, the vibrating body 10 is positive. While being
repelled from the electrode 20L to which a voltage of 0 V is applied, it is attracted to the
electrode 20U to which a negative voltage is applied, and displaced toward the electrode 20U
side (Z direction).
[0020]
As described above, the vibrating body 10 is displaced in the opposite direction of the Z direction
and the Z direction (deflection) according to the acoustic signal, and the displacement direction is
sequentially changed to become vibration, and the vibration state (frequency, amplitude, A sound
corresponding to the phase) is generated from the vibrator 10.
The generated sound passes through at least one of the electrode 20U or the electrode 20L and
is emitted to the outside of the electrostatic speaker 1.
[0021]
In the present embodiment, the conductive thin film layer 12 is not formed with a constant width
from the edge of the film 11 in the portion of the vibrating body 10 between the cushioning
material 40U and the cushioning material 40L.
As described above, since the edge portion of the conductive thin film layer 12 is not sharp
unless the conductive thin film layer 12 is formed on the edge portion of the film 11, a vibrator
in which the conductive thin film layer 12 is formed to the edge portion of the film 11 is used In
this embodiment, no strong electric field is generated at the edge portion of the conductive thin
film layer 12 in this embodiment, and discharge is less likely to occur. Further, in the present
embodiment, a high voltage is applied to the electrodes 20U and 20L to increase the electrostatic
force acting on the vibrating body 10, and the displacement amount of the vibrating body 10 is
04-05-2019
7
also large because the discharge is difficult to occur. You can get a great sound pressure.
[0022]
[Modifications] Although the embodiment of the present invention has been described above, the
present invention is not limited to the above-described embodiment, and can be practiced in
various other forms. For example, the above-described embodiment may be modified as follows
to implement the present invention.
[0023]
In the embodiment described above, the shape of the conductive thin film layer 12 is rectangular
as shown in FIG. 3, but the corner portions of the conductive thin film layer 12 are not made
perpendicular but as shown in FIG. It may be rounded.
[0024]
In the electrostatic loudspeaker according to the present invention, the cushioning material 40 is
not limited to cotton.
It deforms when a force is applied, it returns to its original shape when the applied force is
removed, and it may be another member (such as ester wool) as long as it has insulation and
sound transmission. Good. Further, in the present invention, the shapes of the electrode 20, the
spacer 30, the cushioning material 40, and the vibrating body 10 are not limited to rectangular
shapes, and may be other shapes such as polygons, circles, and ovals. . In the embodiment
described above, only the vibrator 10 is circular or elliptical, and a part of the circumference of
the vibrator 10 is sandwiched between the spacer 30U and the spacer 30L and sandwiched
between the spacer 30U and the spacer 30L. The portions other than the portion may be
sandwiched and supported by the cushioning material 40U and the cushioning material 40L.
Further, in the present invention, in order to prevent an electric shock or a short circuit, the
whole of the electrostatic speaker 1 may be covered with a non-conductive cloth having acoustic
transparency.
[0025]
04-05-2019
8
Moreover, in the embodiment described above, the electrode 20 is formed of a metal having
conductivity in a plate shape, but instead of the electrode 20, a conductive cloth having
conductivity may be used as the electrode. In the configuration using a conductive cloth as an
electrode, as shown in the exploded perspective view of FIG. 5, the conductive thin film layer 12
is not formed with a constant width from the edge portion of the four sides on both sides of the
film 11. Is smaller than the area of the film 11. Further, in the configuration using the conductive
cloth, as shown in FIG. 5, while making the sizes of the conductive cloths 25U, 25L and the
vibrating body 10 the same, the area of the cushioning material 40 is larger than the vibrating
body 10 and the conductive cloths 25U, 25L Make it wider. Then, when assembling the
electrostatic speaker 1, the respective members are stacked in the order of the conductive cloth
25L, the cushioning material 40L, the vibrating body 10, the cushioning material 40U, and the
conductive cloth 25U, and each stacked member is shown in FIG. Stitch together with nonconductive thread 45 in the same manner. In the electrical configuration of the embodiment
using conductive cloths 25U and 25L shown in FIGS. 5 and 6, conductive cloth 25U is connected
to one end of the output side of transformer 50 as shown in FIG. Is connected to the other end of
the output side of the transformer 50. Further, the bias power supply 70 is connected to the
conductive thin film layer 12 of the vibrator 10. Even in such a configuration, since the edge
portion of the conductive thin film layer 12 formed on the film 11 is not sharpened, compared to
the case of using a vibrator in which the conductive thin film layer 12 is formed up to the edge
portion of the film 11 A strong electric field is not generated at the edge portion of the
conductive thin film layer 12 and the discharge is less likely to occur. Even in the configuration
in which the conductive cloths 25U and 25L are used and the spacer 30 is not used, the shape of
the conductive thin film layer 12 may be elliptical or circular as shown in FIG. In the
configuration shown in FIG. 8 as well, power feeding to conductive cloths 25U and 25L is
performed by transformer 50 and wiring (not shown), and power feeding to conductive thin film
layer 12 is also performed by bias power supply 70 and wiring (not shown). It will be.
[0026]
The discharge threshold voltage between the flat plate and the needle electrode is lower
compared to the discharge threshold voltage between the flat plate and the flat plate, and the
discharge threshold voltage between the electrodes is lower when the gap is narrow. Therefore,
in order to make the electrostatic speaker 1 thin, the distance between the vibrator 10 and the
electrodes 20U and 20L is shortened, and the conductive thin film layer 12 is formed up to the
edge of the film 11, and the edges are parallel If it is between the electrode 20U and the
electrode 20L, a discharge is likely to occur between the sharpened portion of the edge of the
conductive thin film layer 12 and the electrode 20 even in the configuration in which the
vibrating body 10 is tensioned. Therefore, in the configuration shown in FIGS. 1 to 3, while both
04-05-2019
9
ends of the X direction of the vibrating body 10 are held between the spacer 30U and the spacer
30L while applying tension to the vibrating body 10, the vibrating body 10 is arranged with the
spacer 30U and the spacer 30L. In the case where the conductive thin film layer 12 is fixed, the
conductive thin film layer 12 may not be formed with a constant width from both ends of the
film 11 in the Y direction. Here, the conductive thin film layer 12 is not formed up to the edge
portion of the film 11 at both ends of the vibrating body 10 in the Y direction, and the edge
portions of both ends in the Y direction of the conductive thin film layer 12 do not become
needle electrodes. Even if the distance from the electrode 20 to the vibrating body 10 is
shortened to make the electrostatic speaker thinner, discharge is less likely to occur at the edge
portions at both ends in the Y direction.
[0027]
FIG. 1 is an external view of an electrostatic speaker 1 according to an embodiment of the
present invention. FIG. 2 is a view schematically showing a cross section and an electrical
configuration of the electrostatic speaker 1. FIG. 2 is an exploded perspective view of the
electrostatic speaker 1; It is a disassembled perspective view of the electrostatic-type speaker
which concerns on the modification of this invention. It is a disassembled perspective view of the
electrostatic-type speaker which concerns on the modification of this invention. It is an external
view of the electrostatic-type speaker which concerns on the modification of this invention. It is
the figure which showed typically the cross section and the electrical constitution of the
electrostatic-type speaker which concerns on the modification of this invention. It is a
disassembled perspective view of the electrostatic-type speaker which concerns on the
modification of this invention.
Explanation of sign
[0028]
DESCRIPTION OF SYMBOLS 1 ... Electrostatic type speaker, 10 ... Vibrator, 11 ... Film, 12 ...
Conducting thin film layer, 20U, 20L ... Electrode, 25U, 25L ... Conductive cloth, 30U, 30L ...
Spacer, 40 U, 40 L ... Cushion material, 45 ... Thread, 50 ... Transformer, 60 ... Input part, 70 ...
Bias power supply
04-05-2019
10
Документ
Категория
Без категории
Просмотров
0
Размер файла
20 Кб
Теги
jp2010016603
1/--страниц
Пожаловаться на содержимое документа