JPH0418316Y2 - - Google Patents

Description

[Detailed description of the invention] Purpose of the invention: [Field of industrial application] This invention relates to improvement of a ring-shaped speaker.

[Prior Art] In a conventional ring-shaped speaker, as shown in FIG.
2 is attached, and its peripheral and central parts are each clamped in a circular shape, and the apex angle α between the diaphragm surfaces on the inner side 13a and the outer side 13b of the voice coil 11 mounting part is set to 180° or less. A V-shaped cross section was used. In addition, in Fig. 4, the reference numeral 11
indicates a magnetic circuit.

[Problems that the invention attempts to solve] Conventional ring-shaped speakers like this
As shown by reference numeral 15 in the figure, sharp peaks and dips occur near the treble limit frequency in the reproduced sound pressure frequency characteristics, resulting in distortion during reproduction.

This invention was made for the purpose of eliminating such drawbacks.

Structure of the invention: As shown in Figs. 1 and 2, the ring-shaped speaker of this invention has a ring-shaped voice coil 2 attached, the periphery of which is clamped in a rectangular shape, and the central part clamped in a circular shape. The configuration is characterized in that it includes an annular diaphragm 3, and in an embodiment, the annular diaphragm 3 has a short side H and a long side L around a rectangular
This includes those characterized by satisfying the condition of 0.6≦H/L≦1. In FIGS. 1 and 2, reference numeral 1 indicates a ceramic circuit, and reference numeral 4 indicates a frame fixed to the ceramic circuit 1.

With this configuration, the apex angle α between the inner 3a and outer 3b diaphragm surfaces of the voice coil 2 mounting portion of the annular diaphragm 3 is α ₀ on the inside of the X′-O cross section, α ₁ on the outside, Assuming that the inside of the B'-O cross section is α ₀ and the outside is α ₂ , there is a magnitude relationship between α ₁ and α ₂ of 0°<α ₁ ≦α ₂ <180°. The apex angle α on the Y′-O cross section is
If the inside is α ₀ and the outside is α ₃ , then α ₁ , α ₂ , α ₃
There is a magnitude relationship between them: 0°<α ₃ <α ₁ ≦α ₂ <180°. The apex angle α in the A-O cross section is α ₀ on the inside and α ₄ on the outside, so α ₄ = α ₂ , and the apex angle α in the X-O cross section is α ₀ on the inside and α 4 on the outside. ₅ , α ₅ = α ₁ , and the apex angle α on the B′-O cross section is α ₀ on the inside,
The outside is α ₆ and α ₆ = α ₂ (= α ₄ ), and the apex angle α on the Y-O cross section is α ₀ on the inside and α ₇ on the outside, so α ₇ = α ₃ . , the apex angle α in the A′-O cross section is α ₀ on the inside,
The outside is α ₈ and the relationship is α ₈ = α ₂ (= α ₆ = α ₄ ). That is, the apex angle α changes from (α ₀ +α ₃ ) to (α ₀ +α ₂ ).

When the apex angle α changes depending on the cross section in this way,
The stiffness Sh at the base of the annular diaphragm 3 where the annular voice coil 2 is attached is Sh=πEtcos ² α/2/sinα/2+K, where E: Young's modulus of the diaphragm t: Thickness of the diaphragm K: It is expressed as a function of the apex angle α as a constant depending on the shape of the diaphragm, and the treble resonance frequency Fh is Fh = 1/2π {Sh (1/Md + 1/Mv)} ^1/2 where, Md: Effective weight of the diaphragm Mv: Weight of the voice coil, so the treble resonance frequency Fh is the vertical angle (α ₀ +
3 by α ₁ ), apex angle (α ₀ + α ₂ ), and apex angle (α ₀ + α ₃ )
It will be distributed as represented by the streets. However, when H/L=1, there is one degeneracy, resulting in two treble resonance frequencies Fh. The characteristic indicated by reference numeral 5 in FIG. 3 is an example of the frequency characteristic when H/L=1.

When the short side H and long side L around the rectangular shape of the annular diaphragm are set in the range of 0.6≦H/L≦1, the average sound pressure level of the peak and dip of the high-frequency resonance characteristic due to the divided vibration of the sound pressure frequency characteristic The deviation from the surface is reduced and the surface can be flattened.

Effects of the invention: Since the apex angle α of the root portion of the voice coil 2 of the annular diaphragm 3 changes gradually in the circumferential direction, the peaks and dips of the high-frequency resonance characteristic due to the divided vibration of the sound pressure frequency characteristic are dispersed and flattened. That is, the composite speaker of this invention can flatten the sound pressure frequency characteristics from the lowest resonance frequency to the treble limit frequency determined by the smallest apex angle α.

[Brief explanation of the drawing]

FIG. 1 is a top view illustrating the composite speaker of this invention, and FIG. 2 is a sectional view of FIG. 1. FIG. 3 shows a sound pressure frequency characteristic diagram. FIG. 4 shows a sectional view illustrating a conventional example. 1, 11... respectively magnetic circuit, 2, 12...
Each voice coil, 3... annular diaphragm, 13
...Annular diaphragm, 4, 14...Frame, 5...
...Sound pressure frequency characteristics of the embodiment of this invention, 15...
Sound pressure frequency characteristics of conventional example.

Claims (1)

[Claims for Utility Model Registration] 1. A ring-shaped speaker characterized by having an annular voice coil attached thereto, an annular diaphragm whose periphery is clamped in a rectangular shape, and whose central portion is clamped in a circular shape. 2. The ring according to claim 1 of the utility model registration claim, characterized in that the annular diaphragm satisfies the condition 0.6≦H/L≦1 between the short side H and long side L of the rectangular periphery. type speaker.