JP2672282B2 - Speaker structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a speaker, and more particularly to a baffle or a frame for supporting and fixing a speaker unit, or an enclosure type unit support for blocking noises from the surface to the air due to resonance and for producing original sound. The present invention relates to the structure of a speaker for faithful reproduction.

[0002]

2. Description of the Related Art In the structure of a speaker, regardless of its shape or model, it is required to faithfully reproduce the original sound while suppressing the resonance of a frame or a baffle for fixing the speaker unit or an enclosure type unit support as much as possible. It In order to meet such demands, the present inventor has published the European Patent No. 531998 and Japanese Utility Model Publication No. 5-7.
The invention disclosed in Japanese Patent No. 4092 is proposed. The surface of the high-rigidity material part such as the baffle is covered with a sound absorbing material to remove the resonance sound of the high-rigidity material part such as the baffle and improve the sound quality of the reproduced sound. There is disclosed a speaker structure in which a sound insulation wall formed of a soundproof sheet having a high internal loss is hermetically sealed.

[0003]

With such a structure, noise due to the resonance of the diaphragm support or the enclosure is not mixed with the original sound. However, since the air itself vibrating due to the vibration of the diaphragm is originally intended for the speaker system, this air vibration secondarily causes the vibration of the object near the diaphragm including the baffle surface. At the very least, it was not possible to prevent the resonance mediated by the air from being mixed into the sound wave due to the pure vibration of the diaphragm only in the above-mentioned prior art. In other words, the flat and heavy soundproof sheet covering the surface of the enclosure or the baffle plate is effective for insulating the resonance sound of the opposite phase from the vibration by the diaphragm support inside, but is Once the sheet starts to resonate due to the force of
The rise and fall are poor, and the original sound is significantly impaired by the inclusion of such resonance. Furthermore, due to the vibration of the soundproof sheet, a part of the original sound is changed into frictional heat before reaching the ear, and there is a possibility that accurate transmission to the ear cannot be ensured. The resonance of such a speaker surface structure is unavoidable, and unlike the resonance of the opposite phase around the diaphragm, it cannot be isolated.

In view of such problems, the present invention not only eliminates the resonance noise of the opposite phase due to the high rigidity material portion such as the baffle, but also adversely affects the resonance of the speaker surface component due to the sound wave generated by the diaphragm. It is intended to provide a structure of a speaker that is minimized.

[0005]

The structure of a speaker according to the present invention comprises a speaker unit and a unit support for supporting and fixing the speaker unit, and at least the entire outer surface of the unit support is made a sound absorbing material. In a speaker having a sound insulation wall formed by sealing the entire surface of the sound insulation sheet with a soundproof sheet having a high internal loss acoustically, a radiation plate made of a hard thin plate is closely attached to the surface side of the soundproof wall. Composed.

Since the radiation plate is directly exposed to the radiation of sound waves, it is desirable to use a material such as fine ceramics, which has a high propagation speed and an excellent attenuation characteristic, but there is a risk that the thin plate is very easily damaged. Considering the above, it is required to have appropriate elasticity. As a material satisfying such requirements, it is preferable to use CFRP baked on the back surface of fine ceramics, a carbon fiber cloth and an epoxy resin coated on a melamine resin plate, or a polycarbonate.

According to such a radiation plate, when a sound wave generated in the air by the diaphragm reaches the speaker surface, the sound wave only vibrates the radiation plate, and the soundproof sheet inside thereof is hardly affected. Absent. Since this radiation plate is light and hard, it quickly rises and falls when resonance occurs, that is, it quickly reflects sound waves from the diaphragm and stops squeaking quickly. Incidentally, such a radiation plate may be appropriately provided with a plywood or other reinforcing material on the inside, and in short, it is sufficient that only the radiation plate resonates while blocking or preventing resonance of the soundproof sheet.

[0008] It is also preferable that a felt be interposed between the radiation plate and the soundproof sheet to ensure that the radiation plate is isolated from the vibration of the soundproof sheet. The felt is provided to block vibration from the soft soundproof sheet to the hard radiation plate. Instead of providing such a felt, the inner surface side of the hard plate or the surface side of the soundproof sheet may be subjected to surface treatment to form innumerable small protrusions.

Further, glass wool, rock wool, etc. are mainly used as the sound absorbing material. By compressing the sound absorbing material from both outsides of the radiation plate with fastening tools such as bolts and nuts to increase the density, low sound is produced. It can be immobile even when pressed against a hard thin plate.

The speaker unit support can have not only a frame or baffle structure but also an enclosure structure, and a high rigidity material such as fine ceramics is desirable as a material constituting the speaker unit, but a sound absorbing material and a soundproof sheet. It is sealed in a sound insulation wall made of, and its resonance sound is shielded by the sound insulation wall. Therefore, a material having a slightly low propagation speed may be used. Therefore, for example, laminated plywood or particle board can be used.

As the soundproof sheet material for further covering the coated surface of the sound absorbing material, one having a high acoustic internal loss is used, and for example, a vibration damping material such as a rubber sheet containing lead powder is preferable.

According to such a speaker structure, since the entire unit support is housed in the sound insulation wall, the resonance sound wave generated by the unit support is not only confined in the sound insulation wall and does not leak to the outside, but also the speaker outer wall is closed. Since it is composed of a hard thin radiating plate, the propagation speed is slow due to the soft soundproof sheet as in the past, resonance noise that is bad in rising and falling is mixed, and part of the reproduced sound is converted into friction heat. It does not get damaged and has extremely excellent transient characteristics.

[0013]

The present invention will now be described in more detail by way of examples with reference to the accompanying drawings. It should be noted that the corresponding components having the same names in the respective embodiments will be described with the same reference numerals.

FIG. 1 shows an embodiment of the present invention.
FIG. 3 is a vertical cross-sectional view showing a structure of a rear open speaker, in which a unit support is a flat baffle having an inverted T shape in a side view,
In the figure, reference numeral 1 is a dynamic speaker unit, 2 is a flat baffle that is a speaker unit support, 3 is a sound insulation wall that houses the flat baffle 2 hermetically, and 4 is a radiation plate.

The plane baffle 2 is made of fine ceramics and has a side surface of an inverted T shape from the vertical plate portion 21 and the horizontal plate portion 22.
The dynamic speaker unit 1 is attached through a unit frame 5 and a machine screw 6 to an opening 23 that is formed in a letter shape and is formed in the upper part of the center of the vertical plate portion.
The material forming the plane baffle 2 is not limited to fine ceramics, but is not limited to glass, ceramics and other high-rigidity materials such as ceramics, hard plastic, and laminated plywood, particle board, and other materials with a slower propagation speed. It can be replaced appropriately.

The speaker unit 1 has a permanent magnet 1 at the center.
2 and a yoke 13 having a U-shaped cross section that accommodates a permanent magnet, and a radial cone 11 that is a vibrating plate is attached to the tip of the yoke. A cone housing 14 is attached to the outside of the cone 11 while being fixed to the outer periphery of the yoke 13.
The tip of the cone housing is fixed to the ring plate-shaped unit frame 5. The unit frame 5 is screwed to the edge portion of the opening 23 of the vertical plate portion 21 with the machine screw 6 as described above.

The flat baffle 2, the high-rigidity material portion of the dynamic speaker unit 1, that is, the cone housing 14 and the yoke 13 are hermetically housed in the sound insulation wall 3. That is, when viewed from the front side, all other parts except the cone 11 of the dynamic speaker unit 1 are housed in the sound insulation wall 3, and the rear surface is entirely covered by the sound insulation wall. The sound insulation wall 3 includes a unit frame 5, a flat baffle 2 and a cone housing 1 of the speaker unit 1.
4, a sound absorbing material 3a of relatively dense glass wool covering the entire surface of No. 4 and the entire exposed surface of the back side of the yoke 13.
A soundproof sheet 3b made of a rubber sheet containing lead powder and further covering the entire covering surface of the sound absorbing material 3a.

A radiation plate 4 is provided on the outer surface of the sound insulation wall 3 via a felt (not shown). The radiation plates 4 on both the front and rear sides are pulled inward by bolts 8 and nuts 8a to be brought into close contact with the soundproof sheet, and by this fastening, the sound absorbing material 3a is also fastened and compressed from both sides to increase the density. That is, the tip side screw portion which is exposed through the through hole passing through the radiation plate 4, the sound insulation wall 3 and the plane baffle 2 through the bolt 8 and faces the opposite side is tightened with the nut 8a. Here, only the plane baffle 2 is formed as a hole 21a that is sufficiently larger than the diameter of the bolt 8 so as not to directly contact the bolt 8 to prevent the vibration of the plane baffle from being transmitted to the bolt.

The radiation plate 4 is made of a polycarbonate having a high propagation speed and a high hardness, and a moderate elasticity with a low risk of breakage. However, other materials that meet such requirements include, for example, melamine resin and CFR.
You may use P or an epoxy resin. When there is a problem in strength such as melamine resin, a thin plywood or the like is appropriately stretched inside for reinforcement as necessary.

The cone housing 14 of the speaker unit 1 may be formed in a cross shape, and in such a case, as shown in FIG. 2, the cone housing 14 covers the cone housing at four intervals, respectively. A through hole H communicating with the back surface may be formed, and the radiation plate 4 may be provided on the front surface. In this case, the string 9 is used instead of the bolt, and the radiation plate 4 is
By squeezing from the outside, the radiation plate at that location is brought into close contact with the sound insulation wall 3.

In such a rear open speaker structure, the operation of the dynamic speaker unit 1 causes the unit support 2 and the yoke 13 of the speaker unit 1.
Further, a resonance sound in a high frequency band is generated in the high rigidity material portion such as the cone housing 14, and the resonance sound is absorbed by the sound absorbing layer 3a covering the surface of the high rigidity material portion, and further the outer side thereof is covered and sealed. The sound is reliably insulated by the extremely flat soundproof wall 3b having the resonance sharpness Q.

Further, even when a part of the reproduced sound due to the vibration of the cone 11 is transmitted to the surface of the speaker body, it reaches the soft soundproof sheet 3b and a resonance sound having a slow propagation speed and a bad rise and fall is generated. It does not convert to frictional heat, and radiates without damaging the original sound with a quick rise.

FIG. 3 shows a speaker structure according to an embodiment of a so-called enclosure type speaker. In the figure, reference numeral 1 is a dynamic speaker unit, 20 is an enclosure type unit support, and 3 is this unit support 2. The sound insulation wall 4a is a radiation plate for hermetically housing.

The unit support 20 is made of particle board in the shape of a box, and has an opening 2 at the center of the front side.
3a is formed, the unit frame 5a and the machine screw 6
The dynamic speaker unit 1 is attached via a.

The unit support 20 is hermetically housed in the sound insulation wall 3. This sound insulation wall 3 contains the sound absorbing material 3a of relatively dense glass wool which covers the entire inner and outer surfaces of the unit support 20 and the lead powder which further covers the entire covering surface of the sound absorbing material 3a, as in the above embodiment. It is composed of a soundproof sheet 3b made of a rubber sheet.

Radiating plates 4a are provided on both the inner and outer sides of the unit support 20 on the outer surface of the sound insulation wall 3 with a felt (not shown). The radiation plate 4 provided on the outer 6 surfaces
The a and the radiation plate 4a provided on the inner six surfaces are pulled inward by bolts 8 and nuts 8a and brought into close contact with the soundproof sheet 3b, and by this fastening, the sound absorbing material 3a is compressed from both sides to increase the density. That is, the tip side threaded portion which faces the opposite side through the bolt 8 through the through hole penetrating the inner and outer radiation plates 4a, the sound insulation wall 3 and the unit support 20 is attached to the nut 8.
It is tightened at a. Here, the unit support 20 has a hole 21 that is sufficiently larger than the diameter of the bolt 8.
As a, it is prevented from directly contacting the bolt 8 to prevent the vibration of the support body from being transmitted to the bolt. Further, although the radiation plate 4a is also provided on the peripheral surface of the sound insulation wall 3 that covers the yoke portion 13 of the speaker unit 1, here, the string 9 is used instead of the bolt to tighten the radiation plate 4a from the outside. The radiation plate is closely attached to the sound insulation wall 3.

Although CFRP is used for the radiation plate 4a in consideration of the speed of propagation, high hardness, and appropriate elasticity, a material satisfying equivalent conditions such as melamine resin, epoxy resin, or polycarbonate may be used. .

Also in such an enclosure type speaker, as in the above-described embodiment, when a part of the reproduced sound due to the vibration of the cone 11 is transmitted to the surface of the speaker body, it reaches the soft soundproof sheet 3b, and the propagation speed is slow and the sound rises. It does not generate a resonance sound that is bad in falling and is not converted into frictional heat, and radiates without damaging the original sound with a quick rising.

[0029]

According to the structure of the speaker of the present invention,
The sound-insulating wall generates a resonance sound that is a source of noise, or absorbs a part of the reproduced sound by attaching a hard thin plate to the surface of the sound-insulating wall that seals the resonator that is the source of noise. As a result, it is possible to provide a speaker structure that reproduces a clear and clear sound without damaging the original sound.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view showing a rear surface open type speaker structure according to the present invention.

FIG. 2 is a sectional view showing a manner of covering a yoke and a cone housing of the speaker unit shown in FIG. 1, as viewed from the back side.

FIG. 3 is a vertical sectional view showing a speaker structure of an embodiment applied to an enclosure type speaker.

[Explanation of symbols]

 1 Dynamic Speaker Unit 11 Cone 12 Permanent Magnet 13 Yoke 14 Cone Housing 2, 20 Unit Support 20a, 21a Through Hole 3 Sound Insulation Wall 3a Sound Absorbing Material 3b Soundproof Sheet 4, 4a Radiator 8 Bolt 8a Nut 9 String

Claims (4)

(57) [Claims] 1. A speaker unit and a speaker unit support for supporting and fixing the speaker unit, wherein at least the entire outer surface of the unit support is covered with a sound absorbing material, and the entire covering surface is further acoustically treated. A speaker structure in which a sound-insulating wall formed by sealing with a sound-proof sheet having high internal loss is formed, and a radiation plate made of a hard thin plate is closely attached to the front surface side of the sound-proof sheet. 2. The structure of the speaker according to claim 1, wherein the radiation plate is made of melamine resin, polycarbonate, CFRP, or epoxy resin material. 3. The structure of the speaker according to claim 1, wherein a felt is interposed between the radiation plate and the soundproof sheet. 4. The structure of the speaker according to claim 1, wherein the sound absorbing material is densified by compressing it from both outer sides of the radiation plate with fasteners.