JP4126809B2 - Speaker - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a loudspeaker used mainly in audiovisual equipment such as a television receiver.
[0002]
[Prior art]
In television receivers, rectangular and elliptical elongated speakers have been used to arrange the speakers on both sides. However, as the cathode ray tube becomes longer, it is required to reduce the width of the speaker. There is also a demand for higher sound quality corresponding to higher image quality on the screen.
[0003]
Here, a conventional elongated speaker will be described with reference to FIGS.
[0004]
3 is a side cross-sectional view of the speaker, FIGS. 4A and 4B are a perspective view and a cross-sectional view of the diaphragm which is the main part, FIG. 5 is a sound pressure frequency characteristic diagram of the speaker using the diaphragm, 6A and 6B are a perspective view and a cross-sectional view of a diaphragm which is a main part of another conventional speaker, and FIG. 7 is a sound pressure frequency characteristic diagram of the speaker using the diaphragm. FIGS. 4 and 6 show a cross-sectional view of the main part with the perspective view of the diaphragm for the purpose of explanation.
[0005]
First, the configuration of the speaker will be described with reference to FIG.
[0006]
According to the figure, the loudspeaker has a ring-shaped magnet 2 and a top plate 3 arranged on a bottom plate 1 having a cylindrical center pole 1a at the center, and an inner periphery of the top plate 3 and a center pole 1a of the bottom plate 1. Then, the magnetic gap 4 is formed, the frame 5 is joined on the top plate 3, the outer periphery is coupled to the frame 5 so that the winding portion of the voice coil 6 is positioned at the center of the magnetic gap 4, The voice coil 6 is supported by a damper 7 whose periphery is coupled to the voice coil 6, the cylindrical bobbin of the voice coil 6 and the central through hole 8 a of the diaphragm 8 are bonded, and the outer periphery of the edge portion 9 of the diaphragm 8 is bonded. A flat portion is provided and bonded and fixed to the frame 5, and a gasket 10 is further bonded and fixed on the flat portion. Reference numeral 11 denotes a dust cap.
[0007]
The operation of the speaker configured as described above will be described below. When an electric input is applied to the voice coil 6 in a parallel magnetic field located at the center of the magnetic gap 4, a force is generated in the vertical direction according to Fleming's left-hand rule. The force is transmitted from the voice coil 6 to the diaphragm 8 through the cylindrical bobbin. The diaphragm 8 generates sound by vibrating the air on the front surface.
[0008]
Next, the diaphragm 8 which is a main part will be described in detail with reference to FIGS. 4A and 4B. The diaphragm 8 is generally composed of four plane portions 8b, 8c, 8d, and 8e, The ridge line 8f is formed by a curved surface R which is a connecting surface at the boundary. FIG. 5 shows the frequency characteristics of a speaker using such a diaphragm.
[0009]
FIG. 6 shows a diaphragm according to another prior art, in which the entire diaphragm is curved in both the major axis and minor axis directions. As is clear from a partial sectional drawing, It was an accumulation of curves from the same direction.
[0010]
5 and 7 show the results of measuring the speaker frequency characteristics by fabricating the diaphragm 8 as a diaphragm having an elliptical shape with a speaker diameter of 20 cm × width 4 cm, and assembling the speaker. .
[0011]
[Problems to be solved by the invention]
However, since the above-mentioned speaker is point-driven at the center of the elongated diaphragm 8 as apparent from FIGS. 5 and 7, the resonance in the major axis direction is likely to occur, and the reproduced sound pressure is low in the middle and high range. A peak dip occurs in the frequency characteristics, resulting in deterioration of sound quality. This has the problem that the diaphragm 8 is weak against surface strength, surface rigidity, torsion, etc., and deteriorates frequency characteristics and sound quality.
[0012]
SUMMARY OF THE INVENTION An object of the present invention is to provide a loudspeaker having excellent sound quality in which a split resonance hardly occurs and a flat frequency characteristic can be obtained while having an elongated structure.
[0013]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, a speaker according to the present invention includes a substantially triangular plane portion having apexes on both short diameter side outer peripheral portions of a central through hole, and an outer edge in a substantially major axis direction from the central through hole excluding the flat portion. The line is a straight line with a curved cross section, and a diaphragm in which the flat part and the curved part are continuous with a curved surface to form a speaker. The combination of the curved surface and the flat surface increases the three-dimensional strength. Thus, a diaphragm that is strong against surface strength, surface rigidity, torsion, and the like can be obtained, and a speaker with an excellent frequency characteristic close to a flat shape can be obtained, in which resonance in an elongated shape hardly occurs.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
According to a first aspect of the speaker of the present invention, there is provided a substantially triangular plane portion having apexes on both short diameter side outer peripheral portions of the central through hole, and a substantially major axis direction from the central through hole excluding the flat portion. The outer edge line is a straight line with a curved cross section, and the plane part and the curved part are continuous with a curved surface to improve the three-dimensional strength by combining the curved surface and the flat surface. constitutes a speaker using a strongly vibration plate, hardly occurs resonance in the elongated and shaped, in which a speaker of excellent frequency characteristic nearly flat can be obtained.
[0015]
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
[0016]
FIGS. 1A and 1B are a perspective view and a cross-sectional view of a diaphragm which is a main part of the speaker of the present invention, and FIG. FIG. 1 shows a perspective view of the diaphragm and a cross-sectional view of the main part for explanation.
[0017]
The diaphragm which is the difference from the prior art will be described with reference to FIG.
[0018]
According to the figure, 18 is a diaphragm, 18a is a central through hole that is coupled to the voice coil 6, and 18b is provided in a substantially triangular shape with the outer peripheral portions of both short diameter sides of the central through hole 18a as vertices. 18c is a curved portion having a straight line extending from the central through hole 18a except for the flat portion 18b to an outer edge line 18d in a substantially longer diameter direction, and a curved section. The flat portion 18b and the curved portion 18c has a continuous shape with a curved surface.
[0019]
In the experiment, the base of the triangular flat portion 18b of the diaphragm 18 was formed to be twice (2a) the width a on the short diameter side, a speaker similar to the prior art was produced, and the sound pressure frequency characteristics were measured. . The measurement results are shown in FIG.
[0020]
According to the figure, it was confirmed that resonance was less likely to occur compared to the conventional ones of FIGS. 5 and 7, and a cappica having a frequency characteristic close to flat was obtained. This is because the three-dimensional strength of the combination of the curved surface and the flat surface is increased by making the substantially triangular flat surface portion 18b on the short axis side of the central portion, and vibration strong against surface strength, surface rigidity, torsion, etc. This is probably because the board was obtained.
[0021]
【The invention's effect】
As described above, the speaker of the present invention can provide a speaker having excellent sound quality because it has an elongated structure but hardly causes split resonance and has a flat frequency characteristic.
[Brief description of the drawings]
1A is a perspective view of a diaphragm which is a main part of a speaker according to an embodiment of the present invention; FIG. 1B is a cross-sectional view of the main part; FIG. Side view of speaker [FIG. 4] (a) Perspective view of diaphragm as main part (b) Cross section of main part [FIG. 5] FIG. 6 (Sound pressure frequency characteristic diagram) [FIG. FIG. 7 is a perspective view of a diaphragm which is a main part of a conventional speaker. FIG. 7 is a sectional view of the main part. FIG.
18 Diaphragm 18a Center through hole 18b Plane portion 18c Curved portion 18d Outer edge line

Claims (1)

A substantially triangular plane portion having apexes at the outer peripheral portions on both short diameter sides of the central through hole, and a curved portion having a straight line from the central through hole excluding the flat surface portion to a substantially major axis direction and a curved section. A speaker having an elongated structure using a diaphragm in which the planar portion and the curved portion are continuously curved to improve the three-dimensional strength and are strong against surface strength, surface rigidity, and torsion .

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