JP2000350286A - Speaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the adverse effect of natural vibration of a diaphragm by providing a characteristics changing means that partially and locally change the characteristics of an elastic component so as to change the amplitude and compliance of some parts of the elastic component. SOLUTION: A fixing member 8 is placed in a notch 5a of a gasket 5 in a direction so that its semicircular end directs in an inner circumferential direction of an edge 2 and a curved face part 8b strikes on the edge 2. Then a fixing screw 9 is inserted to a long hole 8c of the fixing member 8 and screwed to a tapped hole 6c of a frame 6 and fixed. The fixing member 8 is guided by the long hole 8c and the notch 5a of the gasket 5 and the fixed position of the edge 2 in the inner circumferential direction is adjusted by fixing the fixed screw 9 to an optional position of the long hole 8c. Excessive vibration at the resonance of a diaphragm 3 is suppressed to control the motion of the vibration system by adjusting the fixed position of the fixing member 8 so as to locally reduce the stroke of the edge 2 at the position.

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 loudspeaker having diaphragms having different aspect ratios, and particularly to a structure near a spring component such as an edge or a damper for supporting a vibration system including the diaphragm. It relates to a speaker that has been used.

[0002]

2. Description of the Related Art Recently, a thin television (hereinafter, referred to as a thin TV) using a plasma display panel (hereinafter, referred to as a PDP) has been put to practical use. This thin T
As a matter of course, the speaker used for the V is required to have a thin shape. In addition, the screen of the thin TV has been widened, and furthermore, there has been a demand for compactness. Therefore, the installation space of the speakers arranged on both sides of the thin TV is minimized, and the speaker shape viewed from the front is
A vertically elongated shape is required as much as possible.

In order to cope with such a vertically elongated speaker shape, the applicant has previously proposed a speaker suitable for an extremely elongated shape by using a multi-point drive type speaker using a repulsive magnetic circuit. are doing. Specifically, for example, three voice coils are arranged on the center line in the longitudinal direction of a substantially flat and elongated diaphragm, and the speaker is driven by three repulsive magnetic circuits. The structure has already been proposed (JP-A-10-327486, JP-A-10-327486).
-327488, JP-A-10-327497, JP-A-10-327490 and JP-A-10-32749
No. 1).

In a general loudspeaker, a voice coil for driving a vibration system is circular. When a vibration system having a special shape other than a circular shape is driven by a circular voice coil, various distortions occur naturally. However, it is currently difficult to manufacture a voice coil that matches the shape of the special vibration system, and even if it could be manufactured, unless the magnetic circuit parts, such as magnets, were made in a special shape as well, It goes without saying that the efficiency becomes worse. Therefore, in order to realize such a specially-shaped speaker structure, much labor and advanced technology are required.

Therefore, the applicant has already proposed, as a plasma display speaker, a track-type thin speaker as shown in FIG. 7 which is mainly adapted to a thin and thin shape. In this speaker, two magnets of the same polarity, for example, N poles are arranged so as to face each other and repel each other, and a plate made of a soft magnetic material such as iron is sandwiched on the same pole (N pole) surface. Three magnetic circuits 7 that induce repulsive magnetism into the plate and emit the same toward the outer periphery of the plate to generate a constant magnetic flux on the outside of the plate (hereinafter, referred to as a repulsive magnetic circuit)
Is attached to the guide pole portion 6a of the frame 6.

[0006] A voice coil 4 is arranged on the outer periphery of the plate of each repulsion magnetic circuit 7 with a certain clearance. On the outer peripheral portion of the three voice coils 4, one diaphragm 3 having a track shape generated by an outer peripheral line when two circles having the same diameter are connected by a common tangent is mounted. The edge 2 connected to the vibration plate 3 has a pasting portion 2a on the outer periphery thereof which has a track-shaped mounting portion 6b of the frame 6.
It is fixed on the top by fixing means such as an adhesive. Therefore, this speaker has a multi-point drive structure in which one diaphragm 3 is driven by a plurality (three in this example) of repulsive magnetic circuits 7 and voice coils 4.

This thin track-type speaker can prevent divided vibration, ie, swelling and kinking, by multi-point driving in a high frequency band, and has a damperless structure.
The design is such that the lowest resonance frequency fo can be lowered to reproduce a wide frequency band up to a low frequency band.

[0008]

However, in a low frequency band of about 60 Hz, the diaphragm 3 resonates and causes natural vibration, and the central portion of the diaphragm 3 and the portions near both ends in the longitudinal direction are in opposite directions. An oscillating movement occurs. This makes it impossible to reproduce a desired low frequency band. Further, in this state, the vibration system including the diaphragm 3 and the repulsion magnetic circuit 7 are not driven in the vertical direction while maintaining a certain clearance, and in the worst case, the voice coil 4 may hit the repulsion magnetic circuit 7. Such a phenomenon may occur that the sound is fluttered or a fluttering sound is generated from the edge 2 connected to the diaphragm 3.

In order to improve the motion due to the natural vibration while keeping the repulsive magnetic circuit 7 and the voice coil 4 in a circular shape, the applicant has proposed that the center point in the longitudinal direction of the diaphragm 3 be the antinode of resonance. Because it has a large amplitude,
I thought whether it would be possible to cope by suppressing the amplitude of this part. Then, in the vicinity of the center driving portion of the speaker, from the location about 50% of the edge width toward the inside from the outer peripheral side of the edge 2 to the vicinity of the sticking portion 6a, the finger presses down from above to control the amplitude. It was found that the above-mentioned amplitude could be suppressed. That is, it has been found that the movement of the diaphragm 3 due to natural vibration can be suppressed by adjusting the compliance of the spring components such as the edge 2 (or damper) supporting the vibration system including the diaphragm 3.

At present, as a method corresponding to this, the amount of impregnation of the spring component with phenol resin is partially increased,
Several methods have been proposed, such as partially stretching two base fabrics constituting a spring component, and changing the shape of a spring component, that is, an edge or a damper, depending on a location.

However, in the method of partially increasing the impregnation amount of the phenol resin into the spring components, it is difficult to precisely obtain the dimensional accuracy of the increased portion, and it is difficult to control the impregnation amount of the phenol resin. This is a well-known fact. In particular, when the spring component is a damper, increasing the amount of impregnation of the phenolic resin causes clogging of the fiber, which reduces air leakage from the damper in the space separated by the damper, the frame, and the top plate. Hinders

Also, the method of partially stretching two base cloths increases the cost as a matter of course and increases the mass of the whole vibration system, which causes a decrease in the efficiency of the speaker. . Also, in the case of a damper, as in the case of impregnation with a phenol resin, the result is that air escape becomes worse,
It is not always the best approach.

Further, it is an effective method to change the shape of the damper and the edge depending on the location. However, it is necessary to newly form a mold, and this mold is more difficult to manufacture in shape than a normal mold. However, there is a high possibility that time will be required and the cost will increase.

As described above, although various ideas have been proposed, it is difficult to suppress the natural vibration of the diaphragm in accordance with various shapes of the diaphragm of the speaker.

An object of the present invention is to provide a speaker having elongated diaphragms having different aspect ratios by improving the configuration in the vicinity of a spring component such as an edge or a damper for supporting a vibration system including the diaphragm. An object of the present invention is to provide a speaker that reduces adverse effects due to natural vibration of a plate.

[0016]

SUMMARY OF THE INVENTION In view of the above-mentioned object, a loudspeaker according to the present invention comprises a vibration system including elongated diaphragms having different aspect ratios, a part of the vibration system, and the vibration system. And a characteristic changing means for partially changing the characteristic of the spring component locally. This can change the amplitude and compliance of partial locations of the spring components to reduce the adverse effects of natural vibration of the diaphragm.

According to another aspect of the present invention, in the loudspeaker according to the above-mentioned aspect, the characteristic changing means is a fixing member fixed to the spring component so as to partially deform the spring component. Thus, the adverse effect of the natural vibration of the diaphragm can be reduced by adding only a few components to the conventional speaker structure.

According to another aspect of the present invention, in the speaker according to the above aspect, the diaphragm and the spring component are integrally formed, an outer peripheral portion of the spring component is fixed to the frame, and a gasket is fixed on the outer peripheral portion of the frame. The gasket has a projection as a fixing member which acts as a characteristic changing means for hitting and partially deforming a spring component. Thus, the adverse effect of the natural vibration of the diaphragm can be reduced by only partially deforming the existing parts of the conventional speaker.

According to another aspect of the present invention, in the speaker according to the above aspect, the spring component is a conductive damper formed by weaving a conductive part for supplying a current to the voice coil to a stretchable part having a wavy cross section. And the characteristic changing means is:
It is fixed to a terminal ring attached to the outer periphery of the conductive damper, and serves as a fixing member that strikes a spring component and deforms a part thereof. Thereby, in the speaker having the conductive damper as a spring component supporting the diaphragm,
The adverse effect of the natural vibration of the diaphragm can be reduced by adding only a few components.

In another aspect of the present invention, in the speaker according to the invention described above, the spring component is a conductive damper formed by weaving a conductive portion for supplying a current to the voice coil to a stretchable portion having a wavy cross section. And the characteristic changing means is:
It is formed integrally with a terminal ring attached to the outer periphery of the conductive damper, and serves as a protrusion as a fixing member that strikes a spring component and partially deforms it. The adverse effect of the natural vibration of the diaphragm can be reduced only by partially deforming the existing parts of the speaker with the conventional conductive damper.

According to another aspect of the present invention, in the loudspeaker according to each of the above aspects, the fixing member is disposed on a center line in the transverse direction crossing the center of the longitudinal center line of the diaphragm at right angles to the transverse direction. . Thus, the fluttering phenomenon due to the natural vibration of the diaphragm can be effectively suppressed.

According to another aspect of the present invention, in the speaker according to each of the above aspects, the fixing member is configured such that the fixing position thereof is movable. Thereby, even if the frequency and the position where the fluttering phenomenon occurs in the diaphragm are different for each product, the adjustment can be made so as to reduce the adverse effect of the natural vibration in the product. In addition, the tone frequency can be changed by controlling the resonance frequency of the diaphragm.

According to another aspect of the present invention, in the loudspeaker according to each of the above aspects, the diaphragm has a track shape generated by an outer peripheral line when two equal-diameter circles are connected by a common tangent line. As a result, a thin and elongated speaker can be realized.

According to another aspect of the invention, in the loudspeaker according to each of the above aspects, the diaphragm is driven by a number of magnetic circuits and a number of voice coils. Thereby, a multipoint drive type speaker can be realized.

According to another aspect of the invention, in the loudspeaker according to each of the above aspects, the spring component is an edge formed integrally with the diaphragm. Thereby, the adverse effect of the natural vibration of the diaphragm can be reduced at the edge portion which is a spring component supporting the diaphragm.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a speaker according to the present invention will be described below with reference to FIGS. 1 to 3, the same components as those of the conventional example shown in FIG. 7 are denoted by the same reference numerals.

Here, as an embodiment of the speaker according to the present invention, a track type multi-point drive thin speaker for a plasma display (hereinafter, simply referred to as a multi-point drive type speaker) will be described as an example.

This multi-point drive type speaker 1 has a track-shaped diaphragm 3 connected to an edge 2 as a spring component.
, Three voice coils 4, a gasket 5 for pressing one end of the vibration system, a frame 6 holding the vibration system in cooperation with the gasket 5, and three repulsive magnetic circuits 7
, A fixing member 8 and a fixing screw 9.

The frame 6 has a guide pole portion 6a for mounting the repulsion magnetic circuit 7 and the track-shaped diaphragm 3
And a track-like mounting portion 6b for supporting the vibration system including the diaphragm 3 and fixing the margin 2a of the edge 2 as a spring component constituting a part thereof.

As shown in FIG. 2, for example, the fixing member 8 has a shape obtained by extending a semi-track shape to an arbitrary thickness when viewed from a plane, and a lower corner portion of the semicircular end 8a has a front corner. It has a curved surface portion 8b formed in a curved shape when viewed from above.
Further, the fixing member 8 has, at the center thereof, a predetermined length in the direction of the semicircular end portion 8a and a width in which the fixing screw 9 can be inserted, and a long hole 8c penetrating from the top surface to the bottom surface. Are formed. The material of the fixing member 8 is made of, for example, an ABS resin molded product, and is provided with a curved surface portion 8b so that burrs do not cause abnormal noise or damage the edge 2. Bevel the part that comes into contact.

As shown in FIG. 3, the center of the longitudinal center line of the frame 6 is short on the upper surface of the track-shaped mounting portion 6b corresponding to the margin 2a of the edge 2 connected to the diaphragm 3. A fixing member 8 is provided at two places where the center line in the short direction that crosses at right angles to the hand direction intersects the pasting portion 2a of the edge 2.
Is provided with a tapped hole 6c for fixing the hole with a fixing screw 9.

The gasket 5 is formed in a track shape having substantially the same dimensions as the track-shaped mounting portion 6b of the frame 6 to protect the edge 2, and the fixing members 8 are provided at two places corresponding to the tapped holes 6c. A notch 5a having a size that can be accommodated is formed.

First, the diaphragm 3, the three voice coils 4, the gasket 5, the frame 6, and the three repulsive magnetic circuits 7 are assembled by a conventional method. Next, the fixing member 8 is placed in the notch 5 a of the gasket 5 so that the semicircular end 8 a faces the inner circumferential direction of the edge 2 and the curved surface 8 b contacts the edge 2. Next, the fixing screw 9 is screwed into the tapped hole 6c of the frame 6 through the elongated hole 8c of the fixing member 8, and fixed.

The fixing member 8 is guided by the elongated hole 8c and the cutout 5a of the gasket 5, and as shown in the enlarged view of FIG. 1, a fixing screw 9 is fixed to an arbitrary position of the elongated hole 8c. Thereby, the fixed position of the edge 2 in the inner circumferential direction can be adjusted. As described above, by adjusting the fixing position of the fixing member 8 and locally reducing the stroke of the edge 2 at that position, the excessive amplitude at the time of resonance of the diaphragm 3 is suppressed, and the vibration including the diaphragm 3 is suppressed. Control the movement of the system. In addition, as shown in the local enlarged view of FIG. 1B, by setting the height d1 of the fixing member 8 higher than the height d2 of the edge 2, the characteristics of the edge 2 can be changed smoothly. . The height d3 of the gasket 5 is desirably higher than the head of the fixing screw 9, as shown in the figure.

As described above, the fixing member 8 supports the vibration system including the vibration plate 3 and also has the characteristic of partially changing the amplitude and the compliance of the edge 2 constituting a part of the vibration type. Acting as a change means, the problem of the fluttering sound of the edge 2 caused by the natural vibration of the diaphragm 3 and the like is eliminated, and linear driving can be performed. Also, the fixing member 8
By moving and adjusting the fixed position, the resonance frequency of the vibration system including the diaphragm 3 can be controlled to change the timbre.

Although the embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications and applications are possible. For example, in the above-described embodiment, the case where the present invention is applied to the structure of a track type multi-point drive thin speaker for a plasma display has been described. However, the present invention is applicable to general speakers having other forms. Of course there is.

The characteristic changing means, that is, the fixing member 8
Is fixed to 1/2 of the length in the longitudinal direction, which is likely to be an antinode of resonance of the diaphragm 3, as described in the above embodiment.
When the center line is located on the center line, the effect of suppressing fluttering is great, but it can be set at another fixed position. Further, the fixing position may be other than two, that is, one, or three or more.

Further, although the ABS resin is used as the material of the fixing member 8, another resin or another material having the same hardness or different hardness can be used.

Although the fixing member 8 is provided with the long hole 8c so that the fixing position can be adjusted, a round hole may be formed in the fixing member 8 instead of the long hole 8c. In this case, the tapped holes 6c of the frame 6 are formed at arbitrary positions where the amplitude and compliance of the vibration system including the diaphragm 3 can be appropriately changed. The fixing member 8 is inserted into the tapped hole 6c of the frame 6 through the round hole without adjusting the position.
And screw it in.

The fixing member 8 may be provided with another fixing method such as an adhesive without providing the fixing screw 9 insertion hole such as the long hole 8c or the round hole. That is, it may be fixed with an adhesive or the like at an arbitrary position of the track-shaped mounting portion 6b of the frame 6 where the amplitude and the compliance of the edge 2 can be appropriately changed.

The fixing member 8 presses the front side of the edge 2 in the above-described embodiment.
Another fixing member having a structure suitable for holding the back side of the edge 2 may be prepared, and the back surface of the edge 2 may be pressed. further,
Using both this another fixing member and the above-mentioned fixing member 8,
The front and back surfaces of the edge 2 may be pressed. Obviously, in this case, the effect of changing the amplitude and the compliance of the edge 2 increases.

The elongated holes 8 of the fixing member 8 are formed at various positions other than the center thereof, or are formed so as to be in a direction parallel to the longitudinal direction of the edge 2 at the time of use as shown in FIG. You may. Thus, the frequency at which the natural vibration is to be suppressed changes depending on the frequency band to be used, and the frequency of the diaphragm 3 or the edge
Even if the location is different, by moving the fixing position of the fixing member 8 in a direction parallel to the edge 2, it is possible to cope with further various situations. Further, the moving direction of the fixing member 8 may be a direction perpendicular to the longitudinal direction of the edge 2 as shown in FIG. 2 or a direction parallel to the edge 2 as shown in FIG. The angle may be another direction such as an oblique direction such as 315 degrees.

In the above embodiment, the fixing member 8
Are independent members, but the shape of the gasket 5 is partially changed, for example, as shown in FIG.
May be formed in the same shape as the semicircular end portion 8a and the curved surface portion 8b, and the protrusion 5b may be applied to the edge 2 to be deformed.

Further, according to the present invention, in the above-described embodiment,
Although the present invention is applied to a speaker without a damper, a similar effect can be obtained by attaching a fixing member to a damper in a speaker with a damper.

Although the present invention uses a multi-point drive type speaker in the above embodiment, it is needless to say that the present invention can be applied to a one-point drive type speaker.

For example, according to the present invention, as shown in FIG.
A terminal ring 1 previously proposed by the applicant (see JP-A-10-327496) for insulation and for simplifying assembly.
The present invention can also be applied to a single-point drive type speaker using 0 and a conductive damper 11 in which a flat braided tinsel wire 12 serving as a conductive portion is woven into a stretchable portion (damper portion) having a wavy cross section.
In this case, a vibration system including a vibration plate (not shown) is supported, a conductive damper 11 as a spring component constituting a part of the vibration system is fixed, and the flat knitting wire 12 and the terminal 13 are electrically connected. The terminal ring 10 to be connected is formed with a protruding portion 10a protruding inward in the same shape as the semicircular end portion 8a and the curved surface portion 8b of the fixing member 8 described above. Then, the projecting portion 10a can be deformed by contacting the rear surface (or the front surface) of the conductive damper 11.

As described above, the protrusion 10 of the terminal ring 10
“a” acts as a characteristic changing unit that partially changes the characteristics of the vibration system including the diaphragm, that is, the amplitude and the compliance, partially, and can suppress the fluttering of the conductive damper 11 due to the natural vibration of the diaphragm. .

When the present invention is applied to the one-point drive type speaker shown in FIG. 6, as another method of not forming the protruding portion 10a on the terminal ring 10, the terminal ring 10 should be located at a position where fluttering of the conductive damper 11 can be reduced. A fixing hole may be formed, and the fixing member 8 may be attached to the fixing hole as in the above-described embodiment.

The characteristic changing means may have a form capable of suppressing the fluttering by amplifying the amplitude instead of the function of suppressing the amplitude of the spring component. For example, the detachable fixing member may be removed, or a recess may be provided instead of the protrusion.

[0050]

According to the loudspeaker of the present invention, the characteristic of the spring component such as an edge or a damper for supporting the vibration system including the diaphragm, that is, the amplitude and the compliance are partially and partially changed by the characteristic changing means. By doing
It solves problems such as fluttering due to the natural vibration of the diaphragm and enables linear driving.

Further, the characteristic changing means is constituted by a fixing member,
By making the fixing position of the fixing member movable, the resonance frequency of the vibration system can be controlled and the tone can be changed.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a speaker according to the present invention,
(A) is a front view and a local enlarged view, and (B) is a sectional view taken along line AA and a local enlarged view in the front view.

FIG. 2 shows a fixing member in the speaker of FIG. 1,
(A) is a perspective view, (B) is a front view.

FIG. 3 is a perspective view of a frame in the speaker of FIG. 1;

FIG. 4 is a perspective view illustrating another configuration example of the fixing member in the speaker of FIG.

FIG. 5 is a perspective view of a gasket used in another embodiment of the speaker according to the present invention.

FIGS. 6A and 6B are diagrams illustrating still another embodiment of the speaker according to the present invention, wherein FIG. 6A is a front view, and FIG. 6B is a cross-sectional view taken along line BB in the front view and a partially enlarged view.

7A and 7B show a multi-point drive type speaker proposed by the applicant earlier, wherein FIG. 7A is a front view, and FIG. 7B is a cross-sectional view taken along line CC in the front view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Multi-point drive type speaker 2 Edge (spring component) 2a Sticking part 3 Diaphragm 4 Voice coil 5 Gasket 5a Notch 5b Projection (characteristic changing means) 6 Frame 6a Guide pole 6b Track attachment 6c Tap Hole with hole 7 Repulsive magnetic circuit 8 Fixing member (characteristic changing means) 9 Fixing screw 10 Terminal ring 10a Projection (characteristic changing means) 11 Conductive damper (spring component)

Claims (10)

[Claims] 1. A loudspeaker having a vibration system including elongated vibration plates having different aspect ratios and a spring component forming a part of the vibration system and supporting the vibration system,
A loudspeaker comprising characteristic changing means for partially changing the characteristic of the spring component. 2. The loudspeaker according to claim 1, wherein the characteristic changing means is a fixing member fixed to the spring component so as to partially deform the spring component. 3. The diaphragm and the spring component are integrally formed, an outer peripheral portion of the spring component is fixed to a frame, and a gasket is fixed on an outer peripheral portion of the frame.
2. The loudspeaker according to claim 1, wherein the gasket has a protrusion as a fixing member that acts as the characteristic changing unit that strikes the spring component and partially deforms the spring component. 4. The conductive component according to claim 1, wherein the spring component is a conductive damper formed by braiding a conductive portion for supplying a current to a voice coil in a stretchable portion having a wavy cross section. 2. A fixing member fixed to a terminal ring attached to an outer periphery of the damper, the fixing member being configured to strike the spring component and partially deform the spring component.
The described speaker. 5. The conductive component according to claim 1, wherein the spring component is a conductive damper formed by weaving a conductive portion for supplying a current to the voice coil in a stretchable portion having a wavy cross section. The speaker according to claim 1, wherein the speaker is a protrusion that is formed integrally with a terminal ring attached to an outer periphery of the damper and serves as a fixing member that collides with the spring component and partially deforms the spring component. 6. The diaphragm according to claim 2, wherein the fixing member is arranged on a center line in a transverse direction crossing a center of the longitudinal center line of the diaphragm at a right angle in a transverse direction.
The speaker according to 3, 4, or 5. 7. The fixing member according to claim 2, wherein a fixing position thereof is configured to be movable.
The speaker according to 4 or 5. 8. The vibration plate according to claim 1, wherein the diaphragm has a track shape generated by an outer peripheral line when two circles having the same diameter are connected by a common tangent line. Speaker. 9. The speaker according to claim 1, wherein the diaphragm is driven by a number of magnetic circuits and a number of voice coils. 10. The speaker according to claim 1, wherein the spring component is an edge integrally formed with the diaphragm.