close

Вход

Забыли?

вход по аккаунту

?

JP2007243279

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 JP2007243279
An object of the present invention is to provide a speaker diaphragm formed by injection
molding, which can realize expansion of a high frequency reproduction region. According to the
present invention, by mixing polypropylene and a hydrocarbon-based rubber material to improve
fluidity, a speaker diaphragm having a thinnest portion of 120 μm or less can be obtained by
injection molding, and the diaphragm thereof In the speaker using the speaker, it is possible to
realize the expansion of the high-frequency reproduction area by reducing the weight of the
diaphragm. [Selected figure] Figure 1
Loudspeaker diaphragm and speaker and electronic device using the diaphragm
[0001]
The present invention relates to a speaker diaphragm used for various audio devices and video
devices, and a speaker using the same.
[0002]
In order to extend the high-frequency reproduction of the speaker, it is effective to reduce the
weight of the vibration system, and in order to reduce the weight without changing the diameter
of the diaphragm and the material among them, the thickness of the diaphragm is used. You need
to make it thinner.
[0003]
The resin diaphragm mainly composed of polypropylene has a limit of 150 to 200 μm at the
thinnest part in injection molding, and even if the injection speed is increased, it can not be
10-05-2019
1
molded thinner because of the flowability problem.
[0004]
Therefore, the diaphragm whose thinnest part is thinner than the above-mentioned thickness was
obtained by the sheet forming method in which the film is deformed while being stretched after
film forming of the resin pellet of polypropylene.
[0005]
A cross-sectional view of the diaphragm 12 obtained by the conventional sheet forming is shown
in FIG.
In sheet molding, it is possible to obtain a thin diaphragm with a thickness of 120 μm or less,
but since the material thickness of the diaphragm is constant at all locations, the voice coil joint
also becomes thin, the rigidity is low, and the driving force of the voice coil It is difficult to
propagate to high frequencies.
[0006]
As prior art document information related to the invention of this application, for example,
Patent Document 1 is known.
JP-A-58-96492
[0007]
In recent years, with the development of digitization technology, DVD mounted systems have
increased in various audio equipment and video equipment, and wide band reproduction is
required for DVD reproduction, and in particular, expansion of the high region reproduction area
is required. It has become.
[0008]
10-05-2019
2
In order to extend the high frequency reproduction area, it is necessary to reduce the weight of
the vibration system.
Conventional polypropylene resin materials are limited to the thinnest part up to 150 μm in
injection molding, and even if the injection speed is increased by trying to make it thinner, the
flowability of the polypropylene material is poor, and resin filling shortage occurs. The problem
is that a part of the diaphragm is lost.
[0009]
Moreover, in sheet forming, it had a subject in dimensional accuracy and productivity.
Furthermore, since the physical properties are different between the longitudinal direction and
the transverse direction of the film, the vibration mode is non-axial symmetric, and the voice coil
joint of the diaphragm is thin and its rigidity is low. There were issues such as the inability to
[0010]
An object of the present invention is to solve the above-mentioned problems and to provide a
speaker diaphragm formed by injection molding which can realize expansion of a high-frequency
reproduction region.
[0011]
In order to achieve the above object, according to the present invention, the main component of
polypropylene is mixed with a hydrocarbon-based rubber material to improve the fluidity as an
internal lubricant, and the thinnest part is 120 μm or less by injection molding. A speaker
diaphragm having a material thickness.
[0012]
As described above, according to the present invention, since the hydrocarbon rubber material
acts as an internal lubricant at the injection molding temperature to improve fluidity, the speaker
diaphragm having a thinnest portion of 120 μm or less is injection molded It is possible to
obtain
10-05-2019
3
[0013]
As a result, the necessary portions can be molded with an appropriate thickness, and dimensional
accuracy and productivity can also be improved.
In addition, since the difference in physical properties due to the directionality can be reduced in
injection molding, the vibration mode exhibits axial symmetry, and the drive of the voice coil
uniformly propagates, so that the acoustic characteristics are improved.
[0014]
In addition, since the bonding central portion of the diaphragm and the voice coil can be set to an
appropriate thickness, the rigidity becomes high, and the driving force of the voice coil can be
propagated even to high frequencies, and the high frequency reproduction region can be
expanded. it can.
[0015]
Hereinafter, embodiments of the present invention will be described using the drawings.
[0016]
First Embodiment A loudspeaker diaphragm according to a first embodiment of the present
invention will be described below with reference to the drawings.
[0017]
FIG. 1 is a cross-sectional view showing the configuration of the speaker diaphragm in
accordance with the first exemplary embodiment of the present invention.
[0018]
As shown in FIG. 1, the diaphragm 1 is made of polypropylene as a main component, and
injection molding of a material in which a hydrocarbon-based rubber material is mixed is
performed to form the thinnest portion at 120 μm or less.
[0019]
10-05-2019
4
With respect to the material of the diaphragm 1, the hydrocarbon-based rubber material is any of
polybutene, polybutadiene, polyisobutylene and polyisoprene, and may be composed of a mixture
thereof.
[0020]
In addition, the mixing ratio of the hydrocarbon-based rubber material to the polypropylene of
the present invention is set to 0.05 to 0.2 wt%.
[0021]
With this configuration, the mixed hydrocarbon rubber material acts as an internal lubricant
inside the mold to improve the flowability of the resin, so that the thinnest part of the diaphragm
is formed even by injection molding A diaphragm of 120 μm or less can be obtained.
[0022]
Here, if the hydrocarbon-based rubber material is 0.05 wt% or less, it can not have the flowability
necessary for thin-wall molding, and a part of the diaphragm is lost so that the thinnest portion is
120 μm or less Can not be obtained by injection molding.
[0023]
On the other hand, if the content is more than 0.2 wt%, the hydrocarbon-based rubber material
exudes to the surface of the injection-molded diaphragm, which may result in an appearance
defect.
[0024]
As described above, according to the present embodiment, thinning can be achieved, and weight
reduction of the injection-molded diaphragm can be achieved.
[0025]
Since uneven thickness can be obtained by injection molding, the rigidity of the diaphragm can
also be increased by increasing the thickness of the necessary portion.
[0026]
Second Embodiment The inventions of claims 4 to 6 of the present invention will be described
below using a second embodiment.
10-05-2019
5
[0027]
FIG. 2 is a cross-sectional view showing the configuration of the speaker according to an
embodiment of the present invention.
[0028]
The top portion 1A of the diaphragm 1 according to any one of claims 1 to 3 is positioned in
front of both the inner diameter attachment portion 1B and the outer diameter attachment
portion 1C and is bowed to form a half apex of the inner diameter. The angle θ is configured at
45 degrees or less.
[0029]
Further, the inner peripheral portion of the diaphragm 1 is fixed to the voice coil 2, and the voice
coil 2 is centrally supported by a damper 3 whose outer peripheral portion is fixed to the frame
5.
The outer peripheral portion of the diaphragm 1 is fixed to the edge 4, and the edge 4 is further
fixed to the frame 5.
[0030]
In the lower part of the frame 5, a field section 6 composed of a plate 6a, a magnet 6b and a yoke
6c is disposed.
[0031]
This speaker is a so-called mid to high frequency reproduction speaker whose reproduction
frequency band is set in the range of 500 Hz to 100 kHz.
[0032]
With the above configuration, it is possible to realize a high-performance speaker in which the
high frequency reproduction area is expanded.
10-05-2019
6
[0033]
The results will be described below with reference to measured characteristics.
FIG. 3 shows sound pressure frequency characteristics of a speaker using the speaker of the
present embodiment and a diaphragm obtained by conventional sheet molding.
In the speaker using the diaphragm obtained by the conventional sheet forming in FIG. 3, it is
understood that the sound pressure drop is large and the high frequency reproduction is difficult
when the frequency exceeds 20 kHz as shown by the characteristic B.
[0034]
On the other hand, in the loudspeaker according to the present embodiment, as indicated by the
characteristic A, the sound pressure drop is improved more than in the past even if the frequency
exceeds 20 kHz, and it can be confirmed that the high frequency reproduction region is
expanded.
[0035]
Third Embodiment The invention according to the seventh aspect of the present invention will be
described below with reference to the third embodiment.
[0036]
FIG. 4 is an external view of an audio mini-component system which is an electronic device
according to an embodiment of the present invention.
[0037]
As shown in FIG. 4, the speaker 7 of the present invention is incorporated in an enclosure 8 to
constitute a speaker system, and an amplifier 9 as amplification means for an electric signal
input to the speaker 7 and a source input to the amplifier 9 are output. And an electronic minicomponent system 11 for audio.
[0038]
With this configuration, it is possible to realize an excellent electronic device in which the high-
10-05-2019
7
frequency reproduction area, which can not be realized conventionally, is expanded.
[0039]
The speaker diaphragm and the speaker and the electronic device using the diaphragm according
to the present invention are useful for application to electronic devices such as video and audio
equipment which require extension of the high-frequency reproduction region.
[0040]
Cross-sectional view of loudspeaker diaphragm in one embodiment of the present invention
Cross-sectional view of loudspeaker in one embodiment of the present invention Figure showing
a sound pressure frequency characteristic of the loudspeaker in the present invention and the
conventional loudspeaker Fig. 5 is an external view of an electronic device in a sectional view of a
conventional diaphragm for a speaker by sheet molding
Explanation of sign
[0041]
DESCRIPTION OF SYMBOLS 1 diaphragm 1A diaphragm top 1B diaphragm inner diameter
mounting part 1C diaphragm outer diameter mounting part 2 voice coil 3 damper 4 edge 5
frame 6 field part 6a plate 6b magnet 6c yoke 7 speaker 8 enclosure 9 amplifier 10 player 11
mini component system 12 sheet forming diaphragm θ half apex angle
10-05-2019
8
Документ
Категория
Без категории
Просмотров
0
Размер файла
16 Кб
Теги
jp2007243279
1/--страниц
Пожаловаться на содержимое документа