JP3066314B2 - Omnidirectional speaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an omnidirectional speaker, and more particularly to an omnidirectional speaker having excellent omnidirectional characteristics and sound radiation characteristics.

[0002]

2. Description of the Related Art An omnidirectional speaker is used in a wide space such as a sound source for background music, and can be heard as the same sound at any position at the same distance from the speaker.

As a conventional omnidirectional speaker, a large number of acoustic transducers are arranged on the entire surface of a cylinder, and a reproduced audio signal is simultaneously sent to these many acoustic transducers, so that the same reproduced audio is provided at a concentric position. There is a cylindrical speaker that gives you.

However, in the omnidirectional speaker having such a configuration, a large number of speakers must be provided on the surface of the cylinder, which not only complicates the configuration but also complicates the manufacturing process and increases the cost. There is. Also,
Since the same sound is output from each of a large number of acoustic transducers, due to the different arrangement positions of each sound transducer,
There is a possibility that interference of sound waves may occur. Furthermore, in addition to cylindrical speakers, ordinary speakers are equipped with an acoustic transducer on the outer surface of the speaker box and utilize the reverberation inside the speaker box. A standing wave of a sound wave was generated, which also contributed to deterioration of the reproduced sound.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an omnidirectional speaker having a simple structure and excellent omnidirectional characteristics and sound radiation characteristics.

[0006]

In order to solve the above-mentioned problems, an omnidirectional speaker according to the present invention has a spherical inner wall surface, an opening at a lower portion, and an acoustic wave emitting surface at the opening. The speaker is attached so that it is exposed
A speaker box having at least a lower outer surface having a curved surface, and a curved outer shape having a surface facing the center of the sound wave emitting surface as a substantially central portion, wherein the speaker box is separated by at least one support column. A fixed reflecting portion, wherein the reflecting portion is provided with a knob for adjusting the radiation acoustic characteristic and the reflecting portion located above the knob has a cover member having a curved outer shape. It is configured to have.

Here, the curved surface shape is a part of a spherical surface, and the support column is provided upright in a circumferential direction outward from the sound wave radiation surface. The speaker box has a spherical shape except for a portion where the sound wave radiating portion is attached.

[0008]

FIG. 1 is a partially sectional front view of an omnidirectional speaker according to an embodiment of the present invention. In the omnidirectional speaker according to the present embodiment, a plurality of (three in this example) spherical speaker boxes 1 are provided on the support base 2.
And are fixedly held apart by the supporting columns 3A to 3C. As shown in the figure, the speaker box 1 has a flat portion at a lower portion 11 and an opening 12 formed in the flat portion. The speaker 4 is attached to the periphery of the opening 12, and the sound wave emission surface of the speaker 4 is exposed from the opening 12. The support base 2 includes a reflective portion 21 having a curved surface (spherical curved surface) and a base 22 having a flat bottom surface. Here, if the bottom surface of the reflecting section 21 is flat, the base section 22 may be omitted. Support stand 2
Is placed on a flat part such as a floor or a desk.

At any position except the sound wave emitting surface 41 of the speaker 4 between the speaker box 1 and the reflection portion 21, the space is equally spaced in the circumferential direction (equal angle, for example, 120).
(At intervals of three degrees), the three support columns 3A to 3C are fixed, and the mutual positions between the speaker box 1 and the support base 2 are fixed. A knob for adjusting the characteristics of the reproduced radiated sound (volume, sound image localization at the center of the center, three-dimensional effect) and the like are provided on the front portion of the support base 2. In this example, a volume adjustment knob 24 and a sound image localization knob 25 at the center of the center are provided.
And 3D ON / OFF and 3D effect setting knob 26
Is installed. These knobs 24 to 26 are installed at the front part of the reflection part 21, and a cover part 23 having a spherical outer surface is formed on the upper part thereof. The cover 23 has an irregular area where no spherical part is formed because the knobs 24 to 26 of different shapes are provided on the front surface of the reflection part 21, so that the influence of this area is reduced as much as possible. This is for improving the reflection characteristics.

In the above embodiment, the speaker box 1 does not need to have a spherical shape except for the lower part 11, and only the surface part facing the reflecting part 21 which performs sound wave reflection and radiation functions, for example, only the lower half. May have a spherical shape, and the upper portion may have an arbitrary shape.

In the omnidirectional loudspeaker configured as shown in FIG. 1, sound waves radiated from the sound wave radiating surface 41 of the speaker 4 are reflected on the surface of the reflecting portion 21 of the support base 2 and are omnidirectional in the lateral direction. It is radiated toward. At this time,
The reflected and radiated sound waves are omnidirectional as good sound waves without sound wave disturbance because the outer surface of the speaker box 1 is spherical and the outer surface of the reflecting portion 21 of the support base 2 is similarly spherical. Will be radiated. The portion A in FIG. 1 also functions as a part of the horn in terms of acoustic characteristics.

Further, the inside (inner wall) of the speaker box 1 is also spherical, and there is no surface facing the inside unlike a conventional columnar speaker box, so that a sound wave radiated from the speaker as an acoustic transducer to the inner surface. Can prevent the generation of a standing wave that is generated by repeating reflection from the facing surface. That is, since the inner wall surface of the speaker box 1 is spherical, sound waves radiated from the back surface of the speaker 4 inside the speaker box 1 are attenuated by a large number of reflections of the spherical inner surface as shown in FIG. The sound waves emitted from the speaker box 1 to the space without being directly emitted are only the sound waves generated from the speaker 4. As a result, it is possible to prevent or reduce the occurrence of a peak or a dip in the reproduced frequency due to the effect of the standing wave on the radiated sound, and to make the frequency characteristic of the sound radiated from the speaker box 1 nearly flat over the entire band.

Further, in the present embodiment, the surfaces of the spherical speaker box 1 and the reflecting portion 21 of the support base 2 are spherical curved surfaces, respectively, so that sound waves radiated to the outside in all directions of 360 degrees can be prevented. Since the radiating portion structure has a horn structure, the sound reproduced and radiated through the horn structure portion is loaded, the low frequency characteristics of the speaker characteristics can be corrected, and the characteristics can be further improved.

The speaker shown in FIG. 1 can be used alone, but the sound effect can be improved by adding one or more speakers for stereo reproduction. In this case, the cover part 23 and the knobs 24 to 26 may be provided in the other speakers as in FIG. 1, or they may be omitted.

FIG. 2 is a circuit block diagram for obtaining a good reproduced sound according to the present invention. In FIG. 2, a sound source 10
1 is subjected to three-dimensional sound reproduction processing by the three-dimensional sound IC 102, and then amplified by the power amplifier 103. The left audio signal and the right audio signal are sent to the left speaker 1L and the right speaker 1R, respectively. Get stereo playback sound. According to such a configuration, in addition to the features of the speaker of FIG. 1 described above, a three-dimensional sound reproducing IC is set in front of the power amplifier so that a sound full of a sense of reality can be reproduced by the three-dimensional sound effect and the omnidirectionality. become.

[0016]

As described above, according to the omnidirectional speaker of the present invention, the omnidirectional characteristics and the reproduction radiation characteristics can be improved with a very simple structure. In particular, in the present invention, since the inside (inner wall surface) of the speaker box is spherical, it is necessary to prevent the generation of a standing wave that is generated by the sound wave radiated from the speaker to the inner surface being repeatedly reflected from the facing surface. It is possible to prevent and reduce the occurrence of peaks and dips in the reproduced frequency due to the effect of standing waves on the radiated sound, and to make the frequency characteristics of the sound radiated from the speaker box nearly flat over the entire band. Effects can be obtained. Furthermore, since the outer surface is formed with a spherical cover on the upper part of the knob installed on the front of the support base, the acoustic influence of irregular areas where there is no spherical part is reduced as much as possible. The reflection characteristics can also be improved.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional front view of an omnidirectional speaker according to an embodiment of the present invention.

FIG. 2 is a circuit block diagram for obtaining a good reproduced sound in the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Speaker box 1L, 1R Speaker 2 Support base 3A-3C Support pillar 4 Speaker 11 Lower part 12 Opening 21 Reflecting part 23 Cover part 24, 25, 26 Knob 41 Sound emitting surface 101 Sound source 102 Three-dimensional acoustic IC 103 Power amplifier

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04R 1/34 310 H04R 1/02 101

Claims (4)

(57) [Claims] (1)The inner wall is spherical,Has an opening at the bottom
So that the sound emission surface is acoustically exposed to this opening.
The speaker is mounted and at least the lower outer surface is curved
A speaker box having a planar shape,
Has a curved outer shape with the surface facing the center as the approximate center
And the speaker box has at least one support
And a reflector fixedly separated by a column., Knobs for adjusting the radiation acoustic wave characteristics are installed on the reflection section.
That is located at the top of the knob
The projection portion has a cover member having an outer curved surface shape Features
And omnidirectional speaker. 2. The omnidirectional speaker according to claim 1, wherein the curved surface shape is a part of a spherical surface. 3. The omnidirectional speaker according to claim 1, wherein the support column is provided to stand in a circumferential direction outside the sound wave emitting surface. 4. The omnidirectional speaker according to claim 1, wherein the speaker box has a spherical shape except for a portion where the sound wave radiating portion is attached.