JPH06315194A - Speaker - Google Patents

Abstract

PURPOSE:To reduce distortion radiated from the edge of a speaker having an elliptic or rectangular diaphragm, and to flatten a sound pressure frequency characteristic. CONSTITUTION:An edge 11 is divided into two by providing with connecting parts 14 and 15 at almost the centers of the opposed long side edges of an elliptic diaphragm 7. Rolls 12 and 13 divided by the connecting parts 14 and 15 are symmetrically constituted in shape. Those symmetrically constituted projecting roll 12 and recessed roll 13 are connected by the connecting parts 14 and 15 whose cross-section shapes are successively and gradually changed. The synthetic amounts of air displaced by the projecting roll 12 and the recessed roll 13 can be made constant for the up and down amplitude of the edge 11, and the asymmetry of the air displacement amounts can be eliminated. Also, the rigidity of the long side direction of the elliptic or rectangular diaphragm can be suppressed by a reinforcing effect obtained by the connecting parts of the edge.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker, and more particularly to an edge portion thereof.

[0002]

2. Description of the Related Art In recent years, television sets have been made compact, and speakers having an elliptical or rectangular shape with a good space factor, which can be attached to both sides of a cathode ray tube on the front of the television set, have been used.

Below, the conventional elliptical spin as described above is used.
Mosquitoes will be described with reference to the drawings.

FIG. 5 (a) is a top view of a conventional elliptical speaker, and FIG. 5 (b) is a structural sectional view taken along line YY '.
In FIG. 5, 1 is a plate, 2 is a yoke formed integrally with the plate 1, 3 is a magnet fixed to the plate 1, 4 is a center pole fixed to the upper surface of the magnet 3, and 5 is the outer circumference of the center pole 4 and the yoke. Voice coil held in a magnetic gap composed of two inner peripheral surfaces,
6 is a bobbin of the voice coil 5. Reference numeral 7 is an elliptical diaphragm fixed to the tip of the voice coil bobbin 6, 8 is a damper fixed to the outer peripheral portion of the voice coil bobbin 6, 9 is an edge provided on the outer peripheral portion of the elliptical diaphragm 7, and 10 is an outer periphery of the damper 8 and the edge 9. Is a frame for holding a magnetic circuit constituted by the plate 1, the yoke 2, the magnet 3 and the center pole 4 fixedly attached.

In the above structure, when an electric signal is applied to the voice coil 5, a driving force is generated in the voice coil 5 due to the influence of the magnetic field generated between the center pole 4 and the yoke 2, and this driving force is applied to the voice coil bobbin. 6, which causes the elliptical diaphragm 7 fixed to the tip thereof to vibrate.

[0006]

In such a conventional speaker, the elliptical diaphragm 7 is supported by the damper 8 and the edge 9 fixed to the outer peripheral portion of the voice coil bobbin 6,
The linearity of the supporting force of these supports becomes a problem especially during reproduction in the low frequency range where the amplitude becomes large, and is a factor causing harmonic distortion. In order to improve the linearity of such a support, various shapes of the damper 8 and the edge 9 have been devised. As a result, what is most commonly used as the edge 9 at present is a roll shape as shown in FIG. 5, and the linearity of the supporting force of the support is considerably increased by the combination with the corrugated damper 8. It has been improved.

However, the roll-shaped edge includes a distortion component in the sound emitted from the edge. This situation will be described below.

First, the vibration mode of the roll-shaped edge 9 is as shown in FIG. In the figure, A is a neutral state before an electric signal is applied to the voice coil 5, and B is a neutral state.
Indicates a state in which vibration oscillates forward from the neutral point, and C indicates a state in which vibration oscillates rearward from the neutral point. In each vibration state,
Amplitude value ξ where the elliptical diaphragm 7 moves back and forth with respect to the neutral point
Are the same. That is, the edge 9 is not non-linear in its operation as a support for the elliptical diaphragm.

However, the amount of air removed by the edge 9 that oscillates together with the elliptical diaphragm 7 is as shown in FIG.
The amount of air when moving from the position A to the state B is U
Assuming that the amount of air when moving from the position A of 1 to the state of C is U2, the roll shape of the edge is deformed to have different values. That is, the sound pressure characteristic as a speaker is proportional to the sum of the elliptical moving plate 7 and the amount of air removed by the edge 9, but the sound pressure radiated from the edge 9 has the amount of air removed as described above. However, the sound pressure characteristics of the speaker always included a distortion component. Further, in the elliptical speaker, since the rigidity of the diaphragm in the long side direction is weaker than that in the short side direction, it is desirable that the edge has a shape in consideration of the rigidity of the diaphragm to suppress the split resonance in the long side direction as much as possible.

The present invention solves the above-mentioned problems, and significantly reduces the distortion component due to the edge shape without deteriorating the linearity of the supporting force of the edge which is the support of the diaphragm. The purpose is to realize a speaker with less deterioration of sound pressure characteristics due to the edge shape.

[0011]

In order to achieve the above object, a speaker of the present invention comprises a diaphragm having an oval or rectangular outer shape and an edge for supporting the outer periphery of the diaphragm. The edge is configured to have a connecting portion substantially at the center of each side of at least one set of two sets of long sides or short sides facing each other, and the edges divided by the connecting section are adjacent to each other. The feature is that the sides are vertically symmetrical to each other.

[0012]

According to the present invention, the amount of air removed from one side of the edge divided by the connecting portion and the amount of air removed from one side adjacent to the edge are electrically dependent on the amplitude of the diaphragm. It becomes symmetrical with respect to the neutral point where no signal is added, and the combined excluded air amount becomes equal to the vertical amplitude. Further, if the connecting portion is provided at the center of the opposite long sides, the rigidity of the connecting portion can be increased and the split resonance in the long side direction of the rectangular or elliptical diaphragm can be suppressed.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of a loudspeaker according to a first embodiment of the present invention. The sectional structure taken along line XX 'is the same as that of the conventional loudspeaker shown in FIG. 5B. Will be omitted. In the figure, the same components as those of the conventional example shown in FIG.

The structure of the edge 11 is largely different from the conventional example. 12 is a convex roll, 13 is a concave roll,
Reference numerals 14 and 15 are the connecting portions. FIG. 2A shows the connecting portion 1.
4 is a plan view of the vicinity of FIG. 4, and FIG. 4B shows a cross section at each part shown in FIG. As shown in FIG. 2 (b),
The connecting portion 14 approaches the convex divided side roll 12
The diameter of the convex roll is large and the diameter of the concave roll is small, and the diameter of the concave roll is zero in the portion reaching the dividing side 12, and the shape is the same as that of the dividing side 12. On the contrary, the diameter of the concave roll of the connecting portion 14 becomes large and the diameter of the convex roll becomes small as it approaches the divided side roll 13 of the concave roll shape, and the diameter of the convex roll becomes zero in the portion reaching the divided side 13, It has the same shape as the dividing side 13. Since the structure in the vicinity of the connecting portion 15 is exactly the same as the above structure, the description thereof will be omitted.

The operation of the above structure will be described below.
When an electric input is applied to the voice coil 5, the connecting portion 14,
The convex roll 12 and the concave roll 13 connected by 15 operate as a support for the elliptical diaphragm 7 without disturbing the vertical amplitude movement of the elliptical diaphragm 7.

First, when the elliptical diaphragm 7 oscillates upward, the convex roll 12 is in the B state in the vibration state of the roll-shaped edge shown in FIG. 6, that is, the air elimination amount is U1.
On the other hand, the concave roll 13 is obtained by vertically reversing the state of C in the vibration state in the same figure, and the air removal amount is U2.

Next, when the elliptical vibration plate 7 oscillates downward, the convex roll 12 is in the C state in the vibration state of the roll-shaped edge shown in FIG. 6, that is, the air removal amount is U2, and the concave roll is formed. Reference numeral 13 represents the state of B in the vibration state shown in the figure, which is reversed in the vertical direction, and the air removal amount becomes U1.

That is, the combined amount of air removed by the convex roll and the concave roll with respect to the vertical amplitude is constant at U1 + U2 in both cases. Therefore, the second harmonic distortion of the sound pressure due to the asymmetry of the air removal amount at the edge is significantly reduced. Further, the elliptical diaphragm has weaker rigidity in the long side direction than in the short side direction, but
Has a shape in which the diameter of the roll changes in the long side direction, and the rigidity is strong against bending in the long side direction, and has an effect of suppressing split resonance of the elliptical diaphragm 7.

Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 3 shows a plan view of the speaker in the second embodiment of the present invention. In the figure, 20
Is a rectangular diaphragm, 21 is a frame, 16 is a convex roll,
Reference numeral 17 is a concave roll, and 18 and 19 are connecting portions. The difference between this embodiment and the first embodiment is the shape of the diaphragm 20. The edge 22 has the same effect as that of the first embodiment, but if the outer dimensions of the speaker and the frame using the elliptical diaphragm are the same as those of the first embodiment. Since there is a large diaphragm area on the short side, there is an advantage that the reproduced sound pressure level can be improved.

Next, a third embodiment of the present invention will be described with reference to the drawings. FIG. 4 shows a plan view of a speaker according to a third embodiment of the present invention, and the same components as those in the third embodiment are designated by the same reference numerals. In FIG. 4, 24 and 27 are convex rolls, 25 and 26 are concave rolls, and 28, 29, 30, and 31 are connecting portions. As shown in FIG. 2, these connecting portions have a structure in which the shape gradually changes from the adjacent convex roll to the concave roll.
This embodiment differs from the previous embodiments in that the connecting portion is also provided on the short side of the rectangular diaphragm. Along with the vertical amplitude movement of the rectangular diaphragm 20, the amount of air removed by the edge 23 is a combined amount of the convex rolls 24, 27 and the concave rolls 25, 26, and the asymmetric air removal amount is the second. It is improved similarly to the embodiment. When the diaphragm has a high rigidity, such a configuration has an advantage that the distance between the convex roll and the concave roll is reduced, and thus the air removal amount is more uniformly combined.

[0022]

As described above, according to the present invention, the edge shape for supporting the outer periphery of the diaphragm of the elliptical or rectangular diaphragm is defined by at least one edge of two pairs of opposing long sides or short sides. A connecting portion is provided in the center, the edge is divided into a plurality of sides, and adjacent sides have a vertically symmetrical structure. Air that is excluded from one side of the edge with respect to the vertical amplitude of the diaphragm and the adjacent side. By equalizing the combined amount of air removed from one side, the second-order harmonic distortion of the sound pressure characteristic caused by the asymmetry of the air excluded amount that has occurred in the conventional roll-shaped edge is significantly reduced. It is a thing. Further, by providing the connecting portion in the long side direction of the edge, the bending strength in the longitudinal direction of the elliptical or rectangular diaphragm having low rigidity is increased, and the division resonance of the diaphragm is suppressed, so that the sound pressure characteristic is flat. A speaker with low distortion can be provided.

[Brief description of drawings]

FIG. 1 is a plan view of a speaker according to a first embodiment of the present invention.

FIG. 2 is a detailed view of an edge portion of the speaker according to the first embodiment of the present invention.

FIG. 3 is a plan view of a speaker according to a second embodiment of the present invention.

FIG. 4 is a plan view of a speaker according to a third embodiment of the present invention.

FIG. 5 is a structural diagram of a conventional speaker.

FIG. 6 is a diagram showing a vibration state of an edge portion of a conventional speaker.

[Explanation of Codes] 5 Voice coil 7 Elliptical diaphragm 9 Edge 12 Convex roll 13 Concave roll 14, 15 Connecting portion 20 Rectangular diaphragm

Claims (3)

[Claims] 1. A vibrating plate having an outer shape of an ellipse or a rectangle, and an edge for supporting the outer periphery of the vibrating plate, wherein the edge has two long sides or two short sides facing each other.
At least one of the pairs is configured to have a connecting portion substantially in the center of each side, and adjacent edges of the edges divided by the connecting portion are vertically symmetrical to each other. A speaking speaker. 2. The connecting portion has a structure in which two adjacent sides having divided edges are gradually and continuously changed in cross-sectional shape from a convex shape to a concave shape. Speaker. 3. The speaker according to claim 1, wherein the connecting portions are provided on opposite long sides.