JP2000197185A - Speaker for visor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use the oscillation of the minimum resonance frequencies decided by the quality of a magnetic circuit and the rigidity of a suspension, and to satisfactorily reproduce even a low sound band by supporting the magnetic circuit by the suspension. SOLUTION: A cylindrical supporting member 109 is formed at almost the central part of a diaphragm 107, and the outer peripheral part of a circular suspension 111 is mounted on the supporting member 109. A cylindrical first yoke 121 positioned in a recessed part 101 of a frame 103 whose one face is opened is mounted on the inner peripheral part of the suspension 111. A permanent magnet 123 whose outer diameter is set so as to be smaller than the diameter of the inner face of a first yoke 121 and a second yoke 125 are arranged so as to be laminated on the inner bottom face of the first yoke 121. Therefore, a magnetic circuit 127 is constituted of the first yoke 121, permanent magnet 123, and second yoke 125. Thus, the magnetic circuit 127 can be supported by the suspension 111 whose outer peripheral part is mounted on the diaphragm 107.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a buzzer speaker suitable for being incorporated in a visor of an automobile.

[0002]

2. Description of the Related Art In recent years, audio devices such as car stereos are attached to most cars, and music is enjoyed at home even when driving.

[0003] However, speakers of this type of audio equipment are mounted behind a rear seat or in a lower part of a door panel from the viewpoint of easily securing a mounting space.

[0004] Therefore, since sound is heard from behind and below the occupant, there is a problem that the sound is uncomfortable and hard to hear. Therefore, it has been proposed to incorporate a thin speaker in the visor.

As a speaker incorporated in a visor of an automobile (hereinafter, referred to as a visor speaker in the present specification), a full-drive speaker S described in Japanese Utility Model Laid-Open No. 58-19812 as shown in FIG. Proposed.

In the figure, a speaker S has a predetermined yoke plate 3 made of a magnetic material such as iron. A plurality of bar-shaped permanent magnets 4 magnetized are provided, and an air hole 6 is provided between the permanent magnets 4 to release back pressure generated when the diaphragm 5 is driven. .

The air holes 6 also function as sound holes. A support frame 7 for fixing the vibration plate 5 is provided around the yoke plate 3. The vibration plate 5 made of a flexible insulating material such as polyester or polyimide is disposed above the permanent magnet 4 from the magnetic pole surface. It is appropriately fixed to the support frame 7 by a clamp or the like so as to be located slightly apart.

A voice coil 8 is formed on the upper surface of the diaphragm 5 by an electric wire, etching or the like.
Are arranged in a zigzag pattern by sewing between the permanent magnets 4 so that the magnetic flux generated between the magnetic pole surfaces of the voice coil 8 crosses at a right angle. Propulsion is generated, whereby the diaphragm 5 vibrates, and sound is radiated to the outside via the saran net 9.

[0009]

However, in the full-drive speaker having the above-mentioned structure, there is a problem that reproduction of a low-frequency range is not sufficient because the stroke of the diaphragm 5 is short.

[0010] The present invention has been made in view of the above problems, and an object of the present invention is to provide a visor speaker capable of reproducing a bass sound.

[0011]

According to a first aspect of the present invention, there is provided a speaker for a visor comprising a diaphragm and a magnetic circuit supported by a suspension and driving the diaphragm. It is.

Since the magnetic circuit is supported by the suspension, the vibration of the lowest resonance frequency determined by the mass of the magnetic circuit and the rigidity of the suspension can be used, so that the sound can be reproduced well down to the low frequency range.

In the first aspect of the invention, the magnetic circuit may be attached to the diaphragm via a suspension as in the second aspect of the invention, or the magnetic circuit may be mounted on the diaphragm as in the third aspect of the invention. It may be attached to the frame via a cable.

When the magnetic circuit is mounted on the diaphragm via a suspension, the diaphragm preferably has a honeycomb structure from the viewpoint of increasing the strength of the diaphragm.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings. (1) First Embodiment A description will be given with reference to FIGS. FIG. 1 is a sectional view of a visor speaker according to a first embodiment, FIG. 2 is a top view of FIG. 1, and FIG. 3 is an enlarged view of a magnetic circuit portion of FIG.

As shown in FIG. 1, a substantially rectangular diaphragm 1 is provided on a peripheral portion of a frame 103 having a concave portion 101 formed on a bottom surface having one open side via a diaphragm supporting frame 105.
07 is provided. Diaphragm 107 of the present embodiment
Is made of paper and uses a lightweight, highly rigid diaphragm with a honeycomb structure.

At a substantially central portion of the diaphragm 107, a cylindrical support member 109 is provided, and an outer peripheral portion of an annular suspension 111 is attached to the support member 109. The frame 10 is provided on the inner periphery of the suspension 111.
3, a cylindrical first yoke 121 with one surface open is mounted.

On the inner bottom surface of the first yoke 121, a permanent magnet 123 having an outer diameter smaller than the diameter of the inner surface of the first yoke 121 and a second yoke 125 are laminated.

Accordingly, the first yoke 121, the permanent magnet 123, and the second yoke 125 constitute a magnetic circuit 127. Further, as shown in FIG.
Is located in a gap (magnetic gap) between the inner peripheral surface of the first yoke 121 of the magnetic circuit 127 and the peripheral surfaces of the permanent magnet 123 and the second yoke 125, and the coil 131 is disposed on the outer peripheral surface.
Is wound around the bobbin 133.

As shown in FIG. 2, a cover 141 is provided so as to close the frame 103. The cover 141 has a plurality of sound holes 143 formed at predetermined intervals. The operation of the above configuration will be described.

When an electric current is applied to the coil 131, a propulsive force is generated in the coil 131 due to Fleming's left-hand rule, whereby the diaphragm 107 vibrates and sounds to the outside through the sound hole 143 of the lid 141. Is emitted.

According to the above configuration, the magnetic circuit 127 is mounted on the suspension 11 whose outer peripheral portion is attached to the diaphragm 107.
With the support at 1, the vibration of the lowest resonance frequency determined by the mass of the magnetic circuit 127 and the stiffness of the suspension 111 can be used, so that it is possible to satisfactorily reproduce the sound even in the low frequency range.

Further, since the diaphragm 107 has a lightweight and rigid honeycomb structure, a heavy magnetic circuit 127 is provided.
Can be supported. (2) Second Embodiment An example will be described with reference to FIG. In this embodiment, since only the suspension portion of the first embodiment is changed, the same portions as those in FIGS. 1 to 3 showing the first embodiment are denoted by the same reference numerals. , And their description is omitted.

The outer periphery of the magnetic circuit 127 is
3 is attached to the inner peripheral portion of the suspension 201 attached to the suspension 3. Even in such a configuration, the magnetic circuit 12
Since the outer peripheral portion is supported by the suspension 111 attached to the frame 103, the vibration of the lowest resonance frequency determined by the mass of the magnetic circuit 127 and the rigidity of the suspension 201 can be used, so that reproduction can be favorably performed even in a low frequency range.

[0025]

As described above, according to the speaker for a visor of the present invention, since the magnetic circuit is supported by the suspension, the vibration of the lowest resonance frequency determined by the mass of the magnetic circuit and the rigidity of the suspension can be used. Good reproduction up to the bass range is possible.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a visor speaker according to a first embodiment.

FIG. 2 is a top view of FIG.

FIG. 3 is an enlarged view of a magnetic circuit part of FIG. 1;

FIG. 4 is a cross-sectional view of a visor speaker according to a second embodiment.

FIG. 5 is a diagram showing an example of a conventional buzzer speaker.

[Explanation of symbols]

 107 diaphragm 111 suspension 127 magnetic circuit

Claims (4)

[Claims] 1. A loudspeaker for a visor, comprising: a diaphragm; and a magnetic circuit supported by a suspension and driving the diaphragm. 2. The loudspeaker for a visor according to claim 1, wherein said magnetic circuit is attached to a diaphragm via a suspension. 3. The magnetic circuit according to claim 1, wherein the magnetic circuit is mounted on a frame via a suspension.
The visor speaker according to the above. 4. The visor speaker according to claim 1, wherein the diaphragm has a honeycomb structure.