KR200359823Y1 - Amplifying device for driving polyvinylidene fluoride film speaker - Google Patents

Abstract

The present invention relates to an amplifier for driving a polyvinylidene fluoride film speaker, and more particularly, to a drive amplifier device capable of driving a high-impedance PVDF film speaker with a small battery for a small electronic component such as a portable acoustic device. .

The first embodiment of the present invention makes it possible to drive a PVDF film speaker by high voltage amplifying a voice voltage with a BTL type amplifier and a booster using a high magnetic flux density firm alloy or mumetal iron core. In addition, the second embodiment of the present invention converts the DC voltage power supply into an AC voltage power source of several hundred KHz, and boosts it with a booster using ferrite core, thereby making it possible to drive the PVDF film speaker with a small amplification device.

Description

Polyvinylidene fluoride film speaker drive amplification device {AMPLIFYING DEVICE FOR DRIVING POLYVINYLIDENE FLUORIDE FILM SPEAKER}

The present invention relates to an amplifier for driving a polyvinylidene fluoride (hereinafter referred to as "PVDF") film speaker, and has a high impedance with a small battery, especially for small electronic products such as portable acoustic equipment. The present invention relates to a drive amplifier device capable of driving a PVDF film speaker.

As a speaker for converting an electrical signal into sound waves, a magnetic driving method mainly composed of a magnetic diaphragm and a coil has been used. However, as the market for small portable devices increases, there is an increasing demand for lightweight and compact speakers.

However, in the case of the conventional voice coil diaphragm speaker, when the thickness of the magnet is reduced in order to reduce the weight, the size of the magnetic field is also scaled together, thereby limiting the reduction.

Recently, a lot of non-magnetic piezoelectric speakers have been researched and developed. In particular, polyvinylidene fluoride (PVDF) resin has excellent piezoelectricity, is flexible and strong, and is used as a thin film speaker by coating conductors on both sides of PVDF film. .

However, resins such as PVDF and derivatives thereof, or VDF / TrFE (Vinylidene Fluoride / Tri fluoroethylene) not only have a negative impedance of about 2.7 million kg / m 2 .sec, but also produce a thin film speaker using the same. Since it has the characteristics of a condenser, it is necessary to amplify so that the voice voltage delivered to the speaker is about 100V in order to enable the voice impedance to change greatly as the frequency changes and to act as a speaker.

1 is a view showing the configuration of an apparatus for amplifying a voice voltage of a speaker of high impedance, such as a PVDF film speaker according to the prior art. Referring to FIG. 1, when a sound source signal 10 is input, it is configured as a booster 40 that amplifies and boosts it through the amplifier 30. In order to output the voltage to the PVDF film speaker 50, the voltage is increased by using a transformer having a high turns ratio.

However, in order for the PVDF film speaker to be used as a built-in computer built-in device or a portable sound device, an amplifier device including an amplifier 30 and a booster 40 must also be miniaturized, and for a long enough time even with a battery voltage of about 3 to 6V. The speaker must be able to drive.

Theoretically, if the voltage of the power supply 20 is sufficiently raised to about 100V, which is a negative voltage, the amplification device may be very small. However, in this case, it is not practical to obtain a 100V DC voltage power supply using a battery of about 3 to 6V. Therefore, although the input power of the amplifier can be used as 12V to solve the above problems, there is a problem that the size of the booster is still large, and moreover, since a large amount of batteries must be used to operate the battery, portable sound The device is virtually impossible to use, and when a small battery with high voltage is used, the amperage is very low, causing the battery to run out in just a few hours.

Accordingly, an object of the present invention is to provide an amplifier that can drive a PVDF film speaker using a low voltage battery, such as a portable audio device as a power source.

1 is a view showing the configuration of a device for amplifying a voice voltage of a speaker of high impedance, such as a PVDF film speaker according to the prior art.

Figure 2 is a view showing a first embodiment of a drive amplifier for high impedance speaker according to the present invention.

Figure 3 is a view showing a second embodiment of a drive amplifier for high impedance speaker according to the present invention.

4A to 4C are diagrams each showing an embodiment of an amplifying device composed of a DC / AC converter, a booster, and an amplifier according to the present invention.

<Explanation of symbols for the main parts of the drawings>

10: sound source

20: power

30, 130: Amplifier

40, 140: Booster

50: speaker

150: DC / AC converter

In order to achieve the above object, the present invention is a sound source amplification device for driving a PVDF or derivative film speaker thereof, the BTL type amplifier used to primarily increase the voice voltage and the audio voltage output from the BTL type amplifier Provided is a film speaker amplifying apparatus including a booster having a pump alloy or mumetal as an iron core material for boosting to a high voltage of about 100 V.

In still another aspect of the present invention, there is provided a device for amplifying a supply power to a high voltage, the DC / AC converter for converting a DC voltage supplied by a battery power into an AC voltage of several hundred KHz, High voltage amplifier driving a film speaker by amplifying a sound source with a booster having a ferrite as an iron core material for boosting an alternating voltage of several hundred KHz / AC converter converted to a high voltage of about 100 V, and a high voltage power supply of the booster. It also provides a film speaker amplification apparatus comprising a.

Hereinafter, with reference to the accompanying drawings Figures 2 to 4 will be described in detail a preferred embodiment of the PVDF film speaker drive amplifier according to the present invention in detail.

2 is a diagram of a device for raising a voice voltage in a direct audible range to a high voltage as a first embodiment of the voice voltage amplifying apparatus for a high impedance speaker according to the present invention. 2, the amplifier 300 according to the present invention is composed of a BTL type amplifier 330 and a booster 340, and boosts the power source 20 of the voice voltage to the BTL type amplifier 330. It is characterized in that to minimize the size of the booster.

As a preferred embodiment of the present invention, it is preferable to use a material having a high magnetic flux density as the iron core of the booster, and it is preferable to use a pump alloy or mumetal having a high relative permeability, as shown in the table below.

In addition, the lower the power source used, the higher the boost ratio of the booster. For example, when a battery of 3V is used as a power source, the booster must have a boost ratio of 30 times or more, thereby increasing the booster. In order to solve this problem, the present invention uses a single or multiple bit-type amplifiers to raise the voice voltage first.

3 is a view showing a second embodiment of the high-impedance speaker voice voltage amplifier according to the present invention, a form for boosting the power supplied at a low voltage to a high voltage. Referring to FIG. 3, the amplification apparatus 200 according to the present invention is composed of a DC / AC converter 150, a booster 140, and an amplifier 130, and measures the voltage of the power supply 20 supplying a DC voltage. By minimizing the size of the booster by converting it into an AC voltage waveform having a frequency of several hundred KHz, the connected amplifier is characterized by using the high voltage amplifier 130.

4A to 4C are diagrams illustrating an embodiment of an amplifying device including a DC / AC converter, a booster, and an amplifier according to the present invention. 4a to 4c, the supplied low voltage DC power is converted from a DC / AC converter to a high frequency oscillator to hundreds of KHz of alternating current to minimize the size of the booster, and the high voltage output from the booster is used as a power source for the amplifier. Voice voltage is output to the speaker.

The number of turns of the coil wound on the booster decreases as the frequency increases. Therefore, the iron core of the booster used in the present invention can be sufficiently miniaturized even when using a ferrite core, it is preferable to use a ferrite core.

The foregoing has outlined rather broadly the features and technical advantages of the subject innovation in order to better understand the utility model registration claims of the subject matter described below. Additional features and advantages of the utility model registration claims of the present invention will be described below. It should be appreciated by those skilled in the art that the conception and specific embodiment of the present invention can be immediately used as a basis for designing or modifying other structures for carrying out similar purposes to the present invention.

In addition, the inventive concept and embodiments disclosed in the present invention may be used by those skilled in the art as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. In addition, such modifications or altered equivalent structures by those skilled in the art can be variously changed, substituted and changed without departing from the spirit or scope of the invention described in the utility model registration claims.

As described above, the present invention is a method of boosting the voice voltage directly to a high voltage using a VT-type amplifier and an iron core booster made of pump alloy or mumetal, or converting a DC voltage power source into an AC voltage source of several hundred KHz. By converting, boosting with a booster and high voltage amplification, the PVDF film speaker can be driven by a compact and lightweight amplification device.

Claims (3)

In the amplifying device for driving a polyvinylidene fluoride (PVDF) or derivative film speaker thereof, A BTL type amplifier for first boosting a voice voltage supplied from an acoustic device; Booster having a pump alloy or mumetal as an iron core material for boosting the voice voltage output from the BTL type amplifier to a high voltage Film speaker amplification apparatus comprising a. In the amplifying device for driving a polyvinylidene fluoride (PVDF) or derivative film speaker thereof, A DC / AC converter for converting the DC voltage supplied by the battery power source into an AC voltage of several hundred KHz; A booster having a ferrite core as an iron core material for boosting an alternating voltage of several hundred KHz converted by the DC / AC converter to a high voltage of about 100V; And A high voltage amplifier driving the film speaker by amplifying a sound source with the high voltage power supply of the booster. Film speaker amplification device comprising a. The film speaker amplifier of claim 1 or 2, wherein the DC voltage power source comprises a low voltage DC power source of 3 to 6V.