KR20080097634A - Film speaker - Google Patents

Film speaker Download PDF

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Publication number
KR20080097634A
KR20080097634A KR1020070042736A KR20070042736A KR20080097634A KR 20080097634 A KR20080097634 A KR 20080097634A KR 1020070042736 A KR1020070042736 A KR 1020070042736A KR 20070042736 A KR20070042736 A KR 20070042736A KR 20080097634 A KR20080097634 A KR 20080097634A
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KR
South Korea
Prior art keywords
piezoelectric film
film
sound
speaker
film speaker
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KR1020070042736A
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Korean (ko)
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이동수
임상규
박인석
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(주)필스
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Priority to KR1020070042736A priority Critical patent/KR20080097634A/en
Publication of KR20080097634A publication Critical patent/KR20080097634A/en

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R17/00—Piezoelectric transducers; Electrostrictive transducers
    • H04R17/005—Piezoelectric transducers; Electrostrictive transducers using a piezoelectric polymer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
    • B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
    • B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
    • B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
    • B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K9/00—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers
    • G10K9/12—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers electrically operated
    • G10K9/122—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers electrically operated using piezoelectric driving means
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/1051—Piezoelectric or electrostrictive devices based on piezoelectric or electrostrictive films or coatings

Abstract

A film speaker improves sound quality by including a wide sound range by resonating the sound generated in the front and rear vibration of the piezoelectric film in each partition. A piezoelectric film(10) generates a sound pressure by vibrating forward and backward by receiving the current. A resonant plate(30) is fixed in at least one side of a piezoelectric film and has a plurality of partitions(32) by a diaphragm to give the resonance action to the sound generated in the piezoelectric film. A connection terminal(20) is connected to both sides of the piezoelectric film. The partition has one shape of a rectangle or a polygon.

Description

필름 스피커{Film Speaker}Film Speaker {Film Speaker}

도 1은 본 발명에 의한 필름 스피커의 일 실시예를 보인 사시도.1 is a perspective view showing an embodiment of a film speaker according to the present invention.

도 2는 도 1에 따른 필름 스피커의 분해 사시도.2 is an exploded perspective view of the film speaker according to FIG. 1.

도 3은 도 1에 따른 "Ⅲ-Ⅲ"선을 보인 단면도.3 is a sectional view taken along the line "III-III" in FIG.

도 4는 본 발명에 의한 필름 스피커의 다른 실시예를 보인 사시도.Figure 4 is a perspective view showing another embodiment of a film speaker according to the present invention.

도 5는 본 발명에 의한 필름 스피커의 또 다른 실시예를 보인 사시도.5 is a perspective view showing another embodiment of a film speaker according to the present invention.

< 도면의 주요 부분에 대한 부호의 설명 ><Description of Symbols for Main Parts of Drawings>

1 ; 필름 스피커 10 ; 압전필름One ; Film speakers 10; Piezoelectric film

20 ; 접속단자 30 ; 공명판20; Connection terminal 30; Resonance plate

31 ; 격막 32 ; 격실31; Diaphragm 32; Compartment

본 발명은 전기적 에너지를 진동으로 변환시켜 음향을 발생시키는 필름 스피 커에 관한 것이다.The present invention relates to a film speaker that generates sound by converting electrical energy into vibrations.

종래의 음향기기용 스피커는 진동판을 구비한 콘과 공명실인 엔클로저를 구비한 콘스피커로 이루어져서 부피가 크고 무거운 단점이 있었는데, 근래에는 얇고 가벼운 필름 형태의 스피커가 개발되어 소개되고 있다.Conventional loudspeakers for sound equipment consist of a cone with a diaphragm and a cone speaker with an enclosure that is a resonance chamber, which has the disadvantage of being bulky and heavy. Recently, a thin and light film speaker has been developed and introduced.

이러한 필름 스피커는 PVDF(PolyVinylidene Fluoride)나 기타의 수지필름에 플라즈마를 인가하여 친수성을 갖도록 함으로써, 금속이나 전도성 물질이 코팅된 압전필름을 만들고, 이 압전필름에 오디오신호가 인가되면 압전필름이 진동하여 소리를 발생할 수 있도록 한 것이다.Such a film speaker has a hydrophilicity by applying plasma to PVDF (PolyVinylidene Fluoride) or other resin film, thereby making a piezoelectric film coated with a metal or conductive material, and the piezoelectric film vibrates when an audio signal is applied to the piezoelectric film. It is to make a sound.

이러한 필름 스피커에 오디오신호를 인가하기 위해서는 압전필름에 소정의 단자가 구비되며, 필요에 따라 음성신호를 증폭하는 앰프와 매칭용 트랜스포머가 자체적으로 구비될 수 있다.In order to apply an audio signal to the film speaker, a piezoelectric film is provided with a predetermined terminal, and an amplifier and a matching transformer for amplifying a voice signal may be provided by itself if necessary.

그런데, 종래의 필름 스피커는 고음에는 좋으나 아주 낮은 베이스나 강한 음을 출력하는 것에는 충분치 못한 문제가 있다.By the way, the conventional film speaker has a problem that is good for high-pitched sound, but not enough to output very low bass or strong sound.

또한, 필름 스피커가 평탄할 경우에는 음압이 낮기 때문에 사용상 어려움이 있어서 필름 스피커를 소정의 곡률로 굴곡지게 형성해야만 사용이 가능케 되는데, 이와 같이 굴곡된 상태를 유지하기 위해서는 별도의 고정체가 필요하므로 비교적 공간을 많이 차지하게 됨은 물론 원가 상승 및 조립 공정수의 증가를 야기하게 된다.In addition, when the film speaker is flat, the sound pressure is low, so it is difficult to use, and thus the film speaker must be formed to be bent at a predetermined curvature, so that it can be used. Not only does it take up a lot of space, but it also leads to a cost increase and an increase in the number of assembly processes.

본 발명은 이러한 문제점을 해결하기 위한 것으로, 폭넓은 음역을 가질 수 있도록 함으로써 고음뿐만 아니라 중저음의 재생 역시 원활하게 수행할 수 있도록 한 필름 스피커를 제공하는 데 그 목적이 있다.The present invention has been made to solve such a problem, and an object thereof is to provide a film speaker capable of smoothly performing not only high and low bass sounds, but also having a wide range.

또한, 본 발명은 평탄한 상태에서도 음향 출력이 원활하도록 한 필름 스피커를 제공하는 데 다른 목적이 있다.In addition, another object of the present invention is to provide a film speaker that allows a smooth sound output even in a flat state.

상술한 본 발명의 목적은, 전류가 인가됨에 따라 전후 진동하여 음압을 발생시키는 압전필름; 이 압전필름의 적어도 한쪽 면에 고정되며, 압전필름에서 발생된 음향에 공명작용을 부여하도록 격막에 의해 다수의 격실이 구비된 공명판; 상기 압전필름의 양측에 연결되는 접속단자를 포함하는 필름 스피커에 의해 달성된다.An object of the present invention described above, the piezoelectric film for generating a sound pressure by vibrating back and forth as a current is applied; A resonance plate fixed to at least one surface of the piezoelectric film and provided with a plurality of compartments by a diaphragm to impart a resonance action to the sound generated from the piezoelectric film; It is achieved by a film speaker including connection terminals connected to both sides of the piezoelectric film.

이하, 본 발명에 의한 필름 스피커의 실시예를 첨부 도면을 참고하여 설명하면 다음과 같다.Hereinafter, an embodiment of a film speaker according to the present invention will be described with reference to the accompanying drawings.

도 1은 본 발명에 의한 필름 스피커의 일 실시예를 보인 사시도이고, 도 2는 도 1에 따른 필름 스피커의 분해 사시도이며, 도 3은 도 1에 따른 "Ⅲ-Ⅲ"선을 보인 단면도이다.1 is a perspective view showing an embodiment of a film speaker according to the present invention, Figure 2 is an exploded perspective view of the film speaker according to Figure 1, Figure 3 is a cross-sectional view showing a "III-III" line according to FIG.

도 1 내지 도 3에 도시된 바와 같이, 본 발명의 필름 스피커(1)는 크게 압전필름(10)과 접속단자(20) 및 공명판(30)으로 구성된다.As shown in Figures 1 to 3, the film speaker 1 of the present invention is largely composed of a piezoelectric film 10, the connection terminal 20 and the resonance plate 30.

압전필름(10)은 수지필름에 플라즈마를 인가하여 친수성을 갖도록 함으로써, 금속이나 전도성 물질을 코팅하여 제조된다. 즉, 플라즈마를 이용하여 비닐의 한 종류인 PVDF의 전체 표면에 전극을 형성한 것으로서, 비닐의 표면 전체에 전극이 형성되어 있으므로 어느 곳에 전극을 연결하여도 음향을 출력할 수 있고, 유연성이 좋아서 쉽게 구부리거나 말 수도 있으며, 자유로운 형태로 재단하여 다양한 모양으로 제작할 수 있다.The piezoelectric film 10 is manufactured by coating a metal or a conductive material by applying plasma to the resin film to have hydrophilicity. That is, the electrode is formed on the entire surface of PVDF, which is a kind of vinyl, by using plasma. Since the electrode is formed on the entire surface of the vinyl, it is possible to output sound even when the electrode is connected anywhere, and it is easy to be flexible. It can be bent or rolled and can be cut into free shapes to produce various shapes.

이러한 압전필름(10)은 전압을 가할 경우 기계적 진동을 일으켜 표면의 앞면 및 뒷면으로부터 대체로 400Hz 이상의 고주파수 대역의 음향을 출력한다.The piezoelectric film 10 generates mechanical vibration when a voltage is applied, and outputs sound in a high frequency band of about 400 Hz or more from the front and rear surfaces of the surface.

접속단자(20)는 필름 스피커(1)로 출력하기 위한 음향에 대한 전기적인 음향 신호를 음향기기(도시 생략)로부터 수신하기 위한 것으로서, 필름 스피커(1)의 임의의 위치에 형성될 수 있다.The connection terminal 20 is for receiving an electric sound signal for sound for output to the film speaker 1 from an acoustic device (not shown), and may be formed at any position of the film speaker 1.

즉, 위에서 언급한 바와 같이 압전필름(10)의 전체 표면에는 전극이 형성되어 있으므로 접속단자(20)의 형성 위치는 한정될 필요는 없다. 따라서, 접속단자(20)는 압전필름(10)의 상단 또는 측면 등 어느 위치에 전극을 연결하여도 무방하다.That is, since the electrode is formed on the entire surface of the piezoelectric film 10 as mentioned above, the formation position of the connection terminal 20 need not be limited. Therefore, the connection terminal 20 may connect the electrode to any position, such as the top or side of the piezoelectric film 10.

공명판(30)은 압전필름(10)의 어느 한쪽 면에 접착제나 기타 고정부재에 의해 고정되어 압전필름(10)으로부터 발생하는 음향에 공명을 일으켜 보다 향상된 음 질을 제공하게 된다. 특히, 안정적인 공명에 의해 압전필름(10)으로부터 발생되는 저음의 음향을 출력하는 것이 가능하게 된다.The resonance plate 30 is fixed to one side of the piezoelectric film 10 by an adhesive or other fixing member to resonate the sound generated from the piezoelectric film 10 to provide a more improved sound quality. In particular, it is possible to output the sound of the low sound generated from the piezoelectric film 10 by the stable resonance.

이러한 공명판(30)은 소정 높이를 갖는 다수의 격막(31)이 직립 설치되고, 이렇게 설치된 격막(31)에 의해 각 격막(31) 사이에는 전후방이 관통된 다수의 격실(32)이 형성된다. 즉, 격실(32)에서는 압전필름(10)에서 발생되는 음향을 한번 더 공명함으로써 음향 재생을 보다 확실하게 수행할 수 있게 된다.In the resonance plate 30, a plurality of diaphragms 31 having a predetermined height are installed upright, and a plurality of compartments 32 penetrating back and forth between each of the diaphragms 31 are formed by the diaphragm 31 thus installed. That is, in the compartment 32, the sound generated from the piezoelectric film 10 is resonated once more, so that sound reproduction can be more reliably performed.

도 1 내지 도 3에서는 압전필름(10)의 어느 한쪽 면에 공명판(30)이 부착 고정된 것을 도시하였으나, 도 4와 같이 압전필름(10)의 양쪽 면에 모두 공명판(30)이 고정될 수도 있다.1 to 3 illustrate that the resonance plate 30 is fixed to one side of the piezoelectric film 10, the resonance plate 30 may be fixed to both sides of the piezoelectric film 10 as shown in FIG. 4. have.

이와 같이 구성되는 본 발명에 의한 필름 스피커의 작용을 설명하면 다음과 같다.Referring to the operation of the film speaker according to the present invention configured as described above is as follows.

예컨대, 도시하지 않은 음향기기에서 나온 음성신호가 앰프를 통해 소정 레벨로 증폭되고, 이 증폭된 음성신호가 매칭용 트랜스포머를 거치면서 전압이 증폭되며, 이렇게 증폭된 음성신호가 전도성 고분자 또는 금속이 도포된 압전필름(10)에 인가되므로 압전필름(10)이 미세하게 진동하게 된다.For example, a voice signal from an audio device (not shown) is amplified to a predetermined level through an amplifier, and the amplified voice signal is amplified by a matching transformer, and the amplified voice signal is coated with a conductive polymer or metal. Since the piezoelectric film 10 is applied, the piezoelectric film 10 vibrates finely.

이때, 압전필름(10)은 전도성 고분자 또는 금속이 고르게 분포되어 있어 전류 인가시 전도성 고분자 또는 금속이 압전필름(10)에 고르게 음성신호를 전달해 주게 되고, 압전필름(10)은 고르게 전달받은 음성신호에 의해 미세하게 진동함으로써 소리를 발생할 수 있게 되는 것이다. 즉, 압전필름(10)에 고르게 전달된 전류에 의해 압전필름(10)이 초당 수만 번 미세하게 진동함으로써 전기신호를 소리로 바꾸어 주게 된다.At this time, the piezoelectric film 10 has a conductive polymer or metal evenly distributed so that the conductive polymer or metal evenly transmits the voice signal to the piezoelectric film 10 when the current is applied, and the piezoelectric film 10 has the voice signal evenly transmitted. By vibrating finely, it is possible to generate sound. That is, the piezoelectric film 10 vibrates finely tens of thousands of times per second by the current evenly transmitted to the piezoelectric film 10, thereby converting the electrical signal into sound.

이때, 본 발명에서는 필름 스피커가 갖는 기계적인 특성상 400Hz 내지 2kHz 대역의 통상의 음향뿐만 아니라 그 이하의 주파수를 갖는 중저음 영역의 음향에 대해서도 재생 능력이 탁월해진다.At this time, in the present invention, the reproducibility is excellent not only for the normal sound in the 400 Hz to 2 kHz band but also for the sound in the bass region having a frequency lower than that due to the mechanical characteristics of the film speaker.

즉, 다수의 격막(31)에 의해 격실(32)이 형성된 공명판(30)이 압전필름(10)의 일측 또는 양측면에 부착됨으로써, 압전필름(10)의 진동에 의해 발생한 음향이 상기 각 격실(32)의 내부에서 공명 작용을 일으켜 재생 능력이 미약했던 중저음 대역의 출력을 강화할 수 있게 되는 것이다.That is, the resonance plate 30 having the compartments 32 formed by the plurality of diaphragms 31 is attached to one side or both sides of the piezoelectric film 10, so that the sound generated by the vibration of the piezoelectric film 10 is transmitted to the respective compartments ( It is possible to reinforce the output of the bass band, which has a weak reproducing ability, by causing resonance inside the 32).

한편, 도 1 및 도 2의 공명판(30)은 격막(31)이 격자 형태로 이루어져 격실(32)이 장방형으로 이루어진 것이고, 도 4의 공명판(30')은 격실(32')이 원형으로 형성된 것을 도시한 것이다.Meanwhile, the resonance plate 30 of FIGS. 1 and 2 has a diaphragm 31 formed in a lattice shape, and the compartment 32 has a rectangular shape. The resonance plate 30 'of FIG. 4 has a compartment 32' formed in a circular shape. It is shown.

이와 같이, 격막(31)의 높이, 격실(32)(32')의 크기 및 형상은 공명에 의해 강화되는 저음 영역의 주파수와의 관계를 실험적으로 측정함으로써, 출력을 강화시켜야할 저음 영역의 주파수에 따라 임의로 결정될 수 있다. 이는 음원 발생체에서 제공되는 음원 중 특히 강조하여 출력해야할 음원 또는 음향의 주파수 대역이 다양하기 때문이다.As such, the height of the diaphragm 31, the size and shape of the compartments 32 and 32 'are experimentally measured in relation to the frequency of the bass region enhanced by resonance, whereby the frequency of the bass region to which the output should be enhanced. Can be determined arbitrarily. This is because the frequency band of the sound source or sound to be emphasized and output among the sound sources provided by the sound source generator varies.

이상에서 설명한 바와 같이, 본 발명의 필름 스피커에 의하면 다음과 같은 효과가 있다.As described above, the film speaker of the present invention has the following effects.

첫째, 압전필름의 일측 또는 양측면에 다수의 격실이 구비된 공명판을 고정 결합함으로써, 압전필름의 전후 진동시 발생되는 음향을 각각의 격실에서 공명을 일으켜 폭넓은 음대역을 갖게 되므로 음질 향상에 기여할 수 있게 된다.First, by resonating the resonance plate provided with a plurality of compartments on one side or both sides of the piezoelectric film, the resonance generated in the front and rear vibration of the piezoelectric film can be resonated in each compartment to have a wide range of sound so that it can contribute to the improvement of sound quality. Will be.

둘째, 압전필름을 종래와 같이 굴곡지게 형성하지 않고 평탄한 형태로 형성하여도 음향 출력이 원활하게 되므로 별도의 고정체가 필요치 않게 되고 공간 활용도를 높일 수 있게 된다.Second, even if the piezoelectric film is formed in a flat form without being curved as in the prior art, the sound output is smooth, so that a separate fixture is not required and space utilization can be increased.

Claims (2)

전류가 인가됨에 따라 전후 진동하여 음압을 발생시키는 압전필름;Piezoelectric film for generating a sound pressure by vibrating back and forth as a current is applied; 이 압전필름의 적어도 한쪽 면에 고정되며, 압전필름에서 발생된 음향에 공명작용을 부여하도록 격막에 의해 다수의 격실이 구비된 공명판;A resonance plate fixed to at least one surface of the piezoelectric film and provided with a plurality of compartments by a diaphragm to impart a resonance action to the sound generated from the piezoelectric film; 상기 압전필름의 양측에 연결되는 접속단자를 포함하는 것을 특징으로 하는 필름 스피커.Film speaker comprising a connection terminal connected to both sides of the piezoelectric film. 청구항 1에 있어서,The method according to claim 1, 상기 격실은 원형, 장방형 또는 다각형 중 적어도 어느 하나의 형상으로 이루어진 것을 특징으로 하는 필름 스피커.The compartment is a film speaker, characterized in that formed in at least one of the shape of a circle, rectangle or polygon.
KR1020070042736A 2007-05-02 2007-05-02 Film speaker KR20080097634A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013053586A1 (en) * 2011-10-14 2013-04-18 Robert Bosch Gmbh Ultrasonic sensor array
KR20200091132A (en) 2019-01-22 2020-07-30 주식회사 피티지 Directional film and directional speaker module using the same

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013053586A1 (en) * 2011-10-14 2013-04-18 Robert Bosch Gmbh Ultrasonic sensor array
KR20200091132A (en) 2019-01-22 2020-07-30 주식회사 피티지 Directional film and directional speaker module using the same

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