Speaker device

Abstract

To provide a speaker device structured by a piezo speaker in a high-pitched sound region and a dynamic speaker in a bass range, in which an interference between an output of the piezo speaker and an output of the dynamic speaker is suppressed, and the size of speaker device is reduced.SOLUTION: An oscillation film of a piezo speaker 1, provided to a front surface of a housing 7 is oscillated by a dynamic speaker 2 provided so that all of them are existed in an inner part of the housing via a resonance space 3 provided to a back part of the piezo speaker 1.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to improving the performance of a speaker device that uses a speaker that utilizes a piezoelectric element. [Background technology]

[0002] Audio speaker systems generally use dynamic speakers that utilize electromagnetic force. One method for improving the performance of audio speaker systems is the use of piezo speakers, which generate sound using piezoelectric elements and offer excellent response. However, one drawback of piezo speakers is their poor output characteristics in the low-frequency range. A configuration that uses conventional speakers to compensate for the low-frequency range is known (Patent Document 1). As shown in FIG. 4, a piezo speaker 10 for high frequencies and multiple speakers 11 for low frequencies are arranged vertically. Figure 5 shows an example of output characteristics in this patent document. Output characteristic 12 is the output characteristic of the piezo speaker 10 for high frequencies, and output characteristic 13 is the output characteristic of the multiple speakers for low frequencies. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] French Patent Application Publication No. 2393501 Summary of the Invention [Problem to be solved by the invention]

[0004] With the above speaker system, the woofer can compensate for the lack of low-frequency output from the piezo speaker. However, because the speakers are arranged vertically, if the output of the piezo speaker and the woofer interfere with each other, it is necessary to suppress the interference with a separate measure such as an equalizer. Also, because the speakers are arranged vertically, the speaker system becomes large, which makes it unsuitable for small speaker systems such as those used in personal computers.

[0005] To provide a compact speaker device in which a dynamic speaker compensates for the lack of bass output of a piezo speaker, and which suppresses interference between the outputs of the piezo speaker and the dynamic speaker without the need for a separate equalizer or the like. [Means for solving the problem]

[0006] A piezo speaker, which has wider output characteristics in the high frequency range than a dynamic speaker, and a dynamic speaker, which has wider output characteristics in the low frequency range than a piezo speaker, are arranged from the front to the rear of the housing in the following order: piezo speaker, resonance space, dynamic speaker, resonance space, and a sound passage is provided that opens from the resonance space behind the piezo speaker to the front of the housing, and a sound passage is provided that opens from the resonance space behind the dynamic speaker to the front of the housing.Here, the sound passage that opens from the resonance space behind the piezo speaker to the front of the housing surrounds the dynamic speaker, the resonance space behind it, and the sound passage that opens from this resonance space to the front of the housing. [Effects of the Invention]

[0007] By configuring the vibration membrane of the piezoelectric speaker, which is mounted on the front of the housing, to be vibrated by a dynamic speaker, which is mounted so that the entire piezoelectric speaker is inside the housing, via a resonance space provided on the back of the piezoelectric speaker, the high-frequency range of the output of the dynamic speaker is attenuated in the resonance space on the back of the piezoelectric speaker, and good output characteristics can be obtained by eliminating interference between the outputs of the piezoelectric speaker and the dynamic speaker without the need for a separate equalizer or other measure. In addition, by arranging the speakers in the front-to-back direction, the speaker system can be made compact. . [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a front view of an embodiment of the device of the present invention. [Figure 2] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Figure 3] 4 shows output characteristics of an embodiment of the device of the present invention. [Figure 4] FIG. 1 is a cross-sectional view of an embodiment of a prior art document. [Figure 5] 1 shows output characteristics of an example of a prior art document. DETAILED DESCRIPTION OF THE INVENTION ) [Example]

[0009] Fig. 1 is a front view of an embodiment of the device of the present invention, and Fig. 2 is a cross-sectional view of the embodiment of the device of the present invention, in which 1 is a piezo speaker (piezoelectric ceramics bonded to a metal plate), 7 is a housing, and 2 is a dynamic speaker (moving coil type). Piezo speaker 1 has a resonance space 3 and a sound path 5. Dynamic speaker 2 has a resonance space 4 and a sound path 6. The dynamic speaker 2 is placed across the resonant space 3 from the piezo speaker 1. In this configuration, a characteristic of the resonant space 3 is that the higher the frequency, the greater the attenuation of sound. Therefore, of the sounds output from the dynamic speaker 2, sounds in the high frequency range are attenuated as they travel through the resonant space 3, suppressing interference with the output of the piezo speaker 1. The low frequency range sounds, which are less attenuated, excite the diaphragm of the piezo speaker 1, making it possible to compensate for the lack of output in the low frequency range of the piezo speaker 1. Figure 3 shows the output characteristics (schematic diagram) of the device of the present invention. Output characteristic 8 is due to the piezo speaker 1, and output characteristic 9 is due to the diaphragm of the piezo speaker 1 excited by the dynamic speaker 2. The output characteristic of the dynamic speaker 2 is attenuated as the frequency increases. By combining these two characteristics, good characteristics can be obtained from the low to high frequency ranges. .

[0010] Like common audio equipment, the piezo speaker 1 has a resonance space 3 and a sound passage 5, and the dynamic speaker 2 has a resonance space 4 and a sound passage 6, and they have good output characteristics due to the so-called Helmholtz resonance. To adjust the sound quality, it is also possible to add a phase adjustment function for the drive signals of the piezo speaker 1 and the dynamic speaker 2, an equalizer function, or to provide sound-absorbing materials and reflectors inside the housing.

[0011] By arranging the dynamic speaker 2 on the rear side of the piezo speaker 1, a resonance space 3 and sound passage 5 for the piezo speaker 1 and a resonance space 4 and sound passage 6 for the dynamic speaker 2 can be formed between the two side plates of the housing 7, making it possible to make the speaker device compact in size. [Explanation of symbols]

[0012] 1 piezo speaker 2 dynamic speakers 3 Resonance space of piezo speakers 4. Dynamic speaker resonance space 5 Piezo speaker sound path 6 Dynamic speaker sound path 7. Housing 8. Output characteristics of piezo speakers 9. Output characteristics of the diaphragm of a piezoelectric speaker excited by a dynamic speaker 10 Piezo Speaker 11 Low-frequency speaker 12 Piezo speaker output characteristics 13 Output characteristics of low-frequency speakers

Claims

[Claim 1] A speaker device in which a piezo speaker, which has a wider output characteristic in the high frequency range than a dynamic speaker, and a dynamic speaker, which has a wider output characteristic in the low frequency range than a piezo speaker, are arranged from the front to the rear of the housing in the following order: piezo speaker, resonance space, dynamic speaker, resonance space; a sound passage is provided that opens from the resonance space behind the piezo speaker to the front of the housing, and this sound passage is arranged to surround the dynamic speaker, the resonance space behind it, and the sound passage that opens from the resonance space to the front of the housing.

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