close

Вход

Забыли?

вход по аккаунту

JPH01135296

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 JPH01135296
[0001]
TECHNICAL FIELD The present invention relates to a speaker diaphragm used as an acoustic
output device. 2. Related Art In recent years, in the audio characteristics of cassette tape
recorders, microcassette tape recorders, and hi-fi stereo industry, the sound characteristics of
speakers as sound output devices are further output sound pressure and distortion factor more
than before. A speaker with excellent flatness is desired, and a speaker diaphragm that influences
the acoustic characteristics is considered more and more important. The operation of the
conventional loudspeakers 21 and 7 will be described below. Speakers are vibration systems
such as diaphragms and voice coils, magnets and poles. It consists of a magnetic circuit system
consisting of a plate and a yoke. When a voice current flows in a voice coil in a magnetic field
like that, a vertical driving force is generated in the voice coil, and it vibrates according to the
current. This vibration is correctly transmitted to the vibration of the diaphragm and emitted as a
sound wave (for example, Hisao Hayasaka: Introduction to Acoustic Engineering 2 Nikkan Kogyo
Shinbunsha). Problems to be solved by the invention However, the diaphragm of the speaker is
ideally designed to move in a piston over the frequency band to be used, but if the diaphragm is
deformed or split vibration occurs during vibration, the sound pressure-frequency characteristics,
distortion Rate 1 phase characteristics etc. deteriorate and it becomes an obstacle to high fidelity
reproduction. In addition, conventional paper cone diaphragms and plastic diaphragms have low
E / ρ (E: elastic modulus, ;; density) of the moving plate material, low high-resonance frequency,
and can not reproduce the high-frequency speaker There was a drawback of that. SUMMARY OF
THE INVENTION In view of the above problems, the present invention provides a speaker
diaphragm having a high number of high-frequency reproduction limit frequencies 3A-7 with no
deformation of the diaphragm and no divided vibration during vibration. Means for Solving the
Problem To achieve this object, the speaker diaphragm of the present invention is a molded mica
sheet, which is made by forming scaly mica and is impregnated with lacquer, which is a natural
11-05-2019
1
polymer, and heated and pressed. It consists of things. In the present invention, after the mica
having a very high elastic modulus is formed into a sheet by the above-described configuration,
lacquer, which is a natural polymer having a very large internal loss compared to a general
synthetic resin, is impregnated and heated and pressed. Therefore, as a physical property of the
structure, it is possible to realize a diaphragm having an ideal physical property that the elastic
modulus is very high and the internal loss is large due to the effect of sliding between mica layers
or lacquer. EXAMPLE Hereinafter, a speaker diaphragm according to an example of the present
invention will be described. In the speaker according to the embodiment of the present invention,
a laminated mica sheet obtained by forming scaly mica is impregnated with lacquer, and then
heat and pressure is formed to form a diaphragm.
In this diaphragm, a voice coil provided at the tip of a voice coil bobbin is inserted in the
magnetic gap of the magnetic circuit. The operation of the loudspeaker configured as described
above will be described below. The speaker consists of a vibration system such as a diaphragm
and a voice coil, and a magnetic circuit system such as a magnet, a pole, a plate and a yoke.
When a voice current flows in a voice coil in a magnetic field like this, a vertical driving force is
generated in the voice coil to vibrate. This vibration is correctly transmitted to the diaphragm
and emitted as a sound wave. Next, a method of manufacturing the diaphragm will be described.
A scaly mica having a size of 8 to 400 mesh is formed into a laminated mica sheet (thickness 60
μm), and the raw solution (lacquer diluted with toluene) is impregnated with about 20 wt% of
the laminated mica sheet, The diaphragm was molded using a diaphragm molding die at 170 'C
for 30 minutes under rs 1 g 7 cm (7) molding conditions. As described above, according to the
present embodiment, the scaly mica having a very high elastic modulus is laminated in layers,
and the bonding between the layers is made into a composite material using lacquer having a
very large internal loss, thereby forming a diaphragm. As a result, the elastic modulus is high and
the internal loss is also large, and good acoustic characteristics can be obtained. The diaphragm
may have a dome-like shape, a cone-like shape, or a sand-inch flat plate, and good characteristics
can be obtained. Furthermore, although the content rate of lacquer is 20 wt% in this
embodiment, it can be freely changed according to the required physical properties of the
diaphragm, and for example, the internal loss can be increased by increasing the content rate of
lacquer. It is a thing. As described above, according to the present invention, a laminated mica
sheet formed by forming scaly mica is impregnated with lacquer, which is a natural polymer, and
a heat-pressed molded article is used as a diaphragm, and it has an elastic modulus By combining
a large mica and a large lacquer with a high internal loss, it is possible to realize a high elastic
modulus and a high internal loss with little distortion and an excellent high-frequency 6A-7
resonance frequency with excellent acoustic characteristics. A speaker can be provided.
11-05-2019
2
1/--страниц
Пожаловаться на содержимое документа