JPH0775187A - Horn-shaped speaker - Google Patents

Abstract

PURPOSE:To improve tweeter reproduction quality by forming a wall surface so that the cross-sectional area of a throat part formed by a horn inner wall surface and an equalizer wall surface near a diaphragm can be changed toward a horn opening part direction in the manner of an exponent function. CONSTITUTION:An inner wall surface 4a and a wall surface 3a are formed so that the cross-sectional area of a throat part 8 formed by a horn inner wall surface 4a near a diaphragm 2 and the wall surface 3a of an equalizer 3 can be changed toward the direction of an opening part 9 of a horn 4 in the manner of the exponential function. Further, the equalizer 3 is formed so that the cross- sectional shape can be ovaloidal or elliptical. Therefore, a radius R1 of the equalizer 3 and a distance R2 from the outer periphery of the diaphragm 2 to the inner wall surface 4a are not fixed, the crosssectional shape of the horn part near the diaphragm 2 is made discontinuous, and the reduction of acoustic wave outputs caused by phase interference is not concentrated at any specified frequency. On the other hand, since a directional characteristic is longitudinally or laterally set corresponding to the elliptical shape ratio of the horn opening part, directivity control is enabled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a horn type speaker in which an equalizer is arranged, and more particularly to a horn type speaker in which the shapes of the horn and the equalizer are improved so as to be suitable for high frequency range reproduction.

[0002]

2. Description of the Related Art In a conventional horn type speaker, as shown in FIG. 4, a horn sound path is formed by a circular inner wall surface of a horn 14, and a conical equalizer 13 is arranged inside. In FIG. 4, (A) is a plan view and (B) is a cross-sectional view taken along the line ab. The sound wave generated by the vibration of the diaphragm 12 is radiated through the horn sound path, but when the frequency becomes high, the phase of the sound wave emitted from the central part of the diaphragm and the sound wave emitted from the peripheral part is at the neck part of the horn sound path. Because of the deviation, the sound wave output decreases at a frequency equal to or higher than the half-wavelength of the diaphragm radius, and the upper limit of the reproduction frequency is limited. For this reason, the throat unit 18 is set by the equalizer 13 which is a phase equalizer.
Is formed, and the reproduction band in the high frequency range is extended. In the figure, 11 is a voice coil, 15 is a top plate, 16 is a magnet, and 17 is a yoke.

[0003]

However, in the conventional horn type speaker, since the horn inner wall surface and the equalizer are generally circular in cross section, the equalizer 1
The radius R1 of 3 and the distance R2 from the outer circumference of the diaphragm to the inner wall surface of the horn are constant, and therefore the frequency is also constant, so that a phase shift similar to the above-mentioned phase shift occurs, and as shown in FIG. However, there is a drawback in that the output of the sound wave suddenly decreases at a certain frequency or higher.

An object of the present invention is to solve the above-mentioned drawbacks of the conventional horn type speaker and to provide a horn type speaker having improved frequency characteristics in a high frequency range.

[0005]

To achieve the above object, in the horn type speaker of the present invention, the throat portion formed by the inner wall surface of the horn and the equalizer wall surface in the vicinity of the diaphragm has a cross-sectional area in the opening direction of the horn. The inner wall surface of the horn and the wall surface of the equalizer are formed so as to change exponentially toward, and either the inner wall surface of the horn or the equalizer, or both of them have an oval or elliptical cross section. To form.

[0006]

[Function] Since the radius of the equalizer and the distance from the outer periphery of the diaphragm to the inner wall surface of the horn are indefinite, and the cross-sectional shape of the horn portion near the diaphragm becomes discontinuous, the decrease in sound wave output due to phase interference is concentrated at a specific frequency. There is no such thing.

[0007]

1 is a plan view of a horn type loudspeaker according to a first embodiment of the present invention, and FIG. 1 (B) is a sectional view taken along line ab of FIG. 1 (A). In the figure, 1 is a voice coil, 2 is a vibrating plate, 5 is a top plate, 6 is a magnet, and 7 is a yoke, and these configurations are the same as those of the conventional one shown in FIG. In this embodiment, the cross-sectional area of the throat portion 8 formed by the inner wall surface 4a of the horn near the diaphragm 2 and the wall surface 3a of the equalizer 3 changes exponentially in the direction of the opening 9 of the horn 4. Inner wall surface 4a of the horn 4
Also, the wall surface 3a of the equalizer 3 is formed, and further, the equalizer 3 is formed so that its cross-sectional shape is an elliptical shape or an elliptical shape. Therefore, the radius R1 of the equalizer 3
The distance R2 from the outer periphery of the diaphragm to the inner wall surface 4a of the horn becomes indefinite, and the cross-sectional shape of the horn portion near the diaphragm becomes discontinuous, so that the decrease in sound wave output due to phase interference does not concentrate at a specific frequency.

The diaphragm 2 has a dome shape made of titanium and has a diameter of 25 mm, a spherical radius of 19 mm and a thickness of 2.
The one having a thickness of 0 μm is used. The exponential horn is generally formed by the following equation. S = So (Cosh mx + T Sinh mx) 2 where S: horn cross-sectional area So: throat area m: flare coefficient = 4πfc / C fc: cutoff frequency C: sound velocity x: distance from throat T: parameter and T = 1 Those with exponential horns are those with T <1, and those with hyperbolic horns are those with T <1. In the embodiment, the flare coefficient m = 0.7 and the cutoff frequency fc =
It is an exponential horn with T = 1 at 2000 Hz. Further, the shape of the equalizer 3 is set to a ratio of 1 so that the sound wave output reduction due to phase interference is not concentrated at a specific frequency.
It is an ellipse of /1.6 and has a shape in which the peripheral wall portion continuously changes.

FIG. 2 shows a horn type loudspeaker according to the second embodiment. (A) is a plan view and (B) is an ab of FIG.
It is a line sectional view. In this embodiment, the horn 4 has an elliptical shape with a ratio of 1 / 1.6 as in the equalizer 3 of the first embodiment, and the peripheral wall surface of the throat portion 8 is continuously changed so that the equalizer 3 and the horn are changed. Both 4 have an elliptical shape. In the first and second embodiments, the equalizer 3 and the horn 4 have an elliptical shape, but the present invention is not limited to this, and the same effect can be obtained even if the equalizer 3 and the horn 4 have an oval shape that is a deformation of a circle.

FIG. 3 is a frequency characteristic diagram of the horn type speaker according to the first embodiment, and FIG.
As shown in (4), the phase interference occurs at a specific frequency and the sound wave output is reduced. However, it is found that the high frequency characteristics are flattened and significantly improved in the present invention.

[0011]

According to the horn type speaker of the present invention, it is possible to prevent the sound wave output from being lowered due to the phase interference at a specific frequency, and to improve the reproduction in the high frequency range. Further, the directivity can be controlled so that the directional characteristic is set in either the vertical or horizontal direction by the elliptical shape ratio of the horn opening.

[Brief description of drawings]

FIG. 1 shows a horn-type speaker according to a first embodiment of the present invention, (A) is a plan view, and (B) is a sectional view taken along the line ab of (A).

2A and 2B show a horn type speaker according to a second embodiment of the present invention, FIG. 2A is a plan view, and FIG. 2B is a sectional view taken along line ab of FIG.

FIG. 3 is a frequency characteristic diagram of the horn type speaker according to the first embodiment.

FIG. 4 shows a conventional horn-type speaker, (A) is a plan view, and (B) is a sectional view taken along the line ab of (A).

FIG. 5 is a frequency characteristic diagram of a conventional horn type speaker.

[Explanation of symbols]

 1 voice coil 2 diaphragm 3 equalizer 3a equalizer wall 4 horn 4a horn inner wall 5 top plate 6 magnet 7 yoke 8 throat 9 horn opening

Claims (3)

[Claims] 1. In the horns-type speaker, the cross-sectional area of the throat portion 8 formed by the inner wall surface (4a) of the horn and the equalizer wall surface (3a) in the vicinity of the diaphragm (2) has a cross-sectional area in the direction of the opening (9) of the horn 4. The inner wall surface (4a) of the horn (4) and the wall surface (3a) of the equalizer 3 are formed so as to change exponentially toward the
A horn-type speaker characterized in that either a) or the equalizer (3) has an oval or elliptical cross section. 2. The horn-type speaker according to claim 1, wherein the horn inner wall surface (4a) has a circular cross-sectional shape, and the equalizer (3) has an oval shape or an elliptical shape. 3. In the horns-type speaker, the cross-sectional area of the throat part (8) formed by the inner wall surface (4a) of the horn and the equalizer wall surface (3a) near the diaphragm (2) has an opening of the horn (4). The inner wall surface (4a) of the horn (4) and the wall surface (3a) of the equalizer (3) are formed so as to change exponentially in the (9) direction, and the inner wall surface (4a) and the equalizer (3) of the horn are formed. ) A horn-type speaker characterized in that the cross sectional shape thereof is formed into an elliptical shape or an elliptical shape.