JP2000308196A - Loudspeaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a loudspeaker capable of recognizing the information on sound waves while protecting a sounding body. SOLUTION: A loudspeaker 10 is provided with a sounding body 11. The sounding body 11 is composed of hemispherical shell ceramics. The sounding body 11 is arranged on the upper surface of a cabinet 12 and on the upper surface side of the cabinet 12, a lid body 14 covering the sounding body 11 is arranged. Inside the cabinet 12, an LED 15 is arranged and a concave mirror 16 is arranged on the inner surface of the lid body 14. Light from the LED 15 is emitted from an emitting port 17 formed on the cabinet 12 toward the inner surface of the lid body 14, and the concave mirror 16 on the inner surface of the lid body 14 is irradiated and illuminated in the color of light of the LED 15. At such a time, the concave mirror 16 is irradiated with light corresponding to the frequency or level of sonic waves radiated by the sounding body 11 from the LED 15 and the frequency or level of sounds are visually reported.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a speaker,
In particular, the present invention relates to a speaker including a hemispherical shell-shaped piezoelectric ceramic as a sounding body.

[0002]

2. Description of the Related Art As a conventional speaker, the present applicant has
There is an invention that has already been applied for a patent as Japanese Patent Application No. 7-347888 (Japanese Patent Application Laid-Open No. 9-168194). This will be described with reference to the drawings. Speaker 10 shown in FIGS. 2 and 3
0 includes the vibrator 102 serving as a sounding body. Vibrator 102
Is a hemispherical vibrating body 104 made of piezoelectric ceramics.
And an outer electrode 106a and an inner electrode 106b as driving means for vibrating the vibrating body 104 are formed on the outer surface and the inner surface, respectively. The vibrator 102 is fixed to a horn 110 via a spacer 108. The horn 110 is supported by the support pillar 112, and the speaker 100 is configured.

In a speaker 100, when a driving signal is applied between an external electrode 106a and an internal electrode 106b of a vibrator 102, a vibrating body 104 vibrates,
A sound wave is radiated from the outer surface of the vibrator 102 through the horn 110 while a sound wave is radiated from the outer surface of the vibrator 102.

[0004]

However, in the conventional speaker described above, even when the speaker is not used as a speaker, since the sounding body made of a hemispherical shell-shaped piezoelectric ceramic is exposed, impurities adhere to the surface of the piezoelectric ceramic. When the piezoelectric ceramic chipped due to shock or impact, it was a factor that adversely affected characteristics such as a change in sound quality.

In addition, sound waves radiated from the loudspeaker are actually radiated not only in the human audible frequency range but also in a frequency band exceeding the audible frequency range (generally in the range of 15 Hz to 20 kHz). In particular, sound waves radiated from a speaker having a sounding body made of a hemispherical shell-shaped piezoelectric ceramic include sound waves having a frequency of 20 kHz or higher, which is a frequency higher than the audible frequency band, and have a radiation (reproduction) capability in a non-audible frequency band. Has attracted attention as a high speaker.

However, sound waves of 20 kHz or more are
Since the sound wave is inaudible to humans, it is actually 20 kHz
There was no means for determining whether or not a sound wave of z or more was emitted.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems, and provides a speaker that protects a sounding body and that can recognize the frequency and level of a sound wave radiated from the sounding body. Is to do.

[0008]

In order to achieve the above object, a speaker according to the present invention comprises a spherical or hemispherical shell-shaped piezoelectric ceramic and a cabinet in which the sounding body is arranged. A speaker provided on a cabinet so as to cover the sounding body, wherein the lid is opened when sound waves are emitted from the sounding body.

The inner surface of the lid is constituted by a concave mirror, and the cabinet is provided with a light source. The light is emitted from the light source in accordance with the frequency and level (= magnitude of the sound signal) of the sound wave emitted from the sounding body. By changing the color and brightness of the light, the light emitted from the light source is irradiated on the concave mirror, the inner surface of the lid is illuminated with the color of the light, and the frequency and level of the sound wave can be visually recognized. I have.

Further, the light emitted from the light source is 20 k
It is characterized in that sound waves of Hz or higher are emitted in response to emission from the sounding body.

Thus, the speaker does not emit sound waves from the sounding body. That is, when the speaker is not used as a speaker, the speaker is arranged so as to cover the sounding body made of piezoelectric ceramics. Then, when sound is emitted from the sounding body, that is, when used as a speaker, the lid is opened and the inner surface of the lid functions as a sound wave reflector, and the sound wave radiated directly from the sounding body and the lid are used. Are transmitted to the listener.

Further, since the sounding body is made of a spherical or hemispherical piezoelectric ceramic, it has a high ability to reproduce sound waves of 20 kHz or more, which is a non-audible frequency range, and determines whether these sound waves are radiated. The difference in the color of the emitted light according to the frequency and level of the radiated sound wave,
By checking with a concave mirror arranged on the inner surface of the lid,
It becomes possible to recognize visually.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1A and 1B show a speaker 10 according to a first embodiment of the present invention. The speaker 10 includes a sounding body 11. The sounding body 11
It comprises a hemispherical shell-shaped piezoelectric ceramic polarized in the thickness direction, and external and internal electrodes formed on the outer and inner surfaces thereof. The sounding body 11 is arranged so as to be placed on the upper surface of a cylindrical cabinet 12. The cabinet 12 is not particularly limited as long as it is made of a material that functions as a cabinet, such as wood, synthetic resin, and metal. An inverted conical support leg 13 is formed on the lower surface of the cabinet 12. A ball-shaped lid 14 is arranged on the upper surface side of the cabinet 12 so as to cover the sounding body 11.
Is configured.

In the speaker 10, a light source, for example, an LED 15 is provided inside the cabinet 12, and a concave mirror 16 is provided on the inner surface of the lid 14. Then, the light from the LED 15 is emitted from the emission port 17 formed in the cabinet 12 toward the inner surface of the lid 14 and is irradiated on the concave mirror 16 on the inner surface of the lid 14, so that the inner surface of the lid 14 is , LED15.

In the speaker 10 configured as described above,
When no sound is emitted from the sounding body 11, that is, when the speaker 10 is not used, the lid 14 is closed so as to cover the sounding body 11 made of piezoelectric ceramics as shown in FIG. 11 is prevented from adhering to the surface of the sound generator 11, external shock is not directly applied to the sound generator 11, the sound generator 11 is prevented from being cracked or chipped, and sound waves radiated from the sound generator 11 are prevented. The deterioration of the sound quality characteristic is prevented.

When sound is emitted from the sounding body 11, that is, when the speaker 10 is used, the cover 14
1A, the sound wave radiated from the sounding body 11 is directly transmitted to the listener, and the reflected wave having the inner surface of the lid 14 as a reflector is reflected by the listener as shown in FIG. Is propagated to

In this speaker 10, the sounding body 1
The use of a material composed of a hemispherical shell-shaped piezoelectric ceramic as 1 makes it possible to excel in radiation (reproduction) capability in a non-audible frequency band of 20 kHz or more, which exceeds a human audible frequency range of 15 Hz to 20 kHz. There is.

Naturally, sound waves in the non-audible frequency band of 20 kHz or more cannot be detected by humans. However, the sound containing many sound waves of 20 kHz or more is
When a human listens, the outline of the sound is noticeable, and a clear sound is transmitted to the listener.

By visually recognizing that such a sound wave of 20 kHz or more is included in the sound reproduced from the speaker 10, even a listener who is not sensitive to the sound can recognize the sound wave. It is possible to perceive the edge and clarity of the sound in the atmosphere.

Therefore, in the present invention, the LED 15 irradiates the concave mirror 16 on the inner surface of the lid 14 with light having a color and brightness corresponding to the frequency and level of the sound wave radiated by the sounding body 11 and reproduced. It visually informs the frequency and level of the sound being present (the magnitude of the sound wave signal).

Therefore, in FIG. 1A, LE
There is only one D15, one for 100 Hz or less, one for 100-1 kHz,.
You may make it prepare the LED according to each frequency band, such as one for kHz or more.

In the speaker 10 according to the first embodiment described above, the sounding body 11 has a hemispherical shell-like structure, but may be a sounding body made of a spherical shell-like piezoelectric ceramic. . Further, the shape of the cabinet 12 is not limited to a cylindrical shape, but may be a rectangular tube shape, and the upper surface of the cabinet does not need to be parallel to the installation surface, and may be non-parallel to the installation surface. The shape of the lid 14 is not limited to the ball shape, but can be appropriately selected according to the use of the speaker 10 such as a cylindrical shape or a rectangular tube shape.

[0023]

As described above, in the loudspeaker according to the present invention, no sound wave is emitted from the sounding body made of piezoelectric ceramics. That is, when the sounding body is not used as a speaker, the lid is arranged so as to cover the sounding body, and the sounding body is sounded. If sound is emitted from the body, that is, if it is used as a speaker,
When the speaker is not used, the sounding body may be cracked or chipped due to external shocks or environmental changes, and the external electrodes may be damaged when the speaker is not used. Deterioration is prevented, and the sound quality of the speaker is kept good. In particular, a speaker using a sounding body made of piezoelectric ceramics, which is prone to cracking and chipping,
The present invention is effective.

Further, since the sounding body is made of a spherical or hemispherical shell-shaped piezoelectric ceramic, it has a high ability to reproduce sound waves in the non-audible frequency range of 20 kHz or more, and determines whether these sound waves are radiated. Can be visually recognized by checking the difference in color of light emitted according to the frequency of the emitted sound wave with a concave mirror arranged on the inner surface of the lid.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a structure of a speaker according to a first embodiment of the present invention, (a) showing a state when a speaker is used, and (b) a perspective view showing a state when a speaker is not used. is there.

FIG. 2 is a perspective view showing a structure of a conventional speaker.

FIG. 3 is a cross-sectional view illustrating a structure of a conventional speaker.

[Explanation of symbols]

 Reference Signs List 10 speaker 11 sounding body 12 cabinet 14 lid 15 LED 16 concave mirror

Claims (3)

[Claims] 1. A sounding body made of a piezoelectric ceramic having a spherical or hemispherical shell shape, a cabinet in which the sounding body is arranged, and a lid provided in the cabinet so as to cover the sounding body. And a speaker comprising:
The speaker is characterized in that the lid is opened when sound waves are emitted from the sounding body. 2. An inner surface of the lid is formed by a concave mirror,
The cabinet is provided with a light source, the color and brightness of light emitted from the light source are changed according to the frequency and level of sound waves emitted from the sounding body, and the light emitted from the light source is transmitted to the concave mirror. The loudspeaker according to claim 1, wherein the illumination illuminates the inner surface of the lid with the color of the light, so that the frequency and level of the sound wave can be visually confirmed. 3. The light emitted from the light source is 20 kHz.
The loudspeaker according to claim 2, wherein a sound wave of z or more is emitted in response to emission from the sounding body.