JPH11168795A - Electroacoustic transducer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electroacoustic transducer, capable of obtaining a flat sound pressure over an entire frequency band by having a planar diaphragm vibrate integrally without divided vibration. SOLUTION: Peak parts 70a1-70a7 arranged in parallel on a diaphragm 70 are constituted of division parts T1-T5, U1-U5, V1-V5, W1-W5, X1-X5, Y1-Y5 and Z1-Z5 in a direction perpendicular to the longitudinal direction. Since driving force of the diaphragm is uniform over an entire surface, generation of undesirable vibrations such as divided vibration or the like are prevented and a flat sound pressure is obtained over the entire frequency band.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electroacoustic transducer which is a flat speaker.

[0002]

2. Description of the Related Art FIG. 3 is a view for explaining a conventional electroacoustic transducer. FIG. 3A is a front view of the electroacoustic transducer, and FIG. Sectional view, FIG.
FIGS. 3A and 3B are diagrams for explaining a diaphragm constituting the electroacoustic transducer, wherein FIG. 3A is a front view of the diaphragm, and FIG. 3B is a vertical cross-sectional view of the diaphragm taken along line AA ′. FIG. 5 is a diagram comparing the sound pressure frequency characteristics of the electroacoustic transducer of the present invention with the sound pressure frequency characteristics of a conventional electroacoustic transducer.

As shown in FIGS. 3 (A) and 3 (B), an overall-drive thin speaker unit A, which is an electroacoustic transducer, includes a frame 1, a rear plate 2, a magnet 3, a pole piece 4, a guide pin 5, a boiler. A coil 6, a diaphragm (diaphragm) 7, a damper 8, and an edge 9 are roughly constituted. The area of the diaphragm can be increased by increasing the number of combinations (segments) of the magnet 3, the boil coil 6, and the diaphragm (diaphragm) 7. The dimensions of the speaker unit A are, for example, a thickness of 25 mm,
The width is 115 mm, the height is 136 mm, the maximum amplitude is 10 mmp-p (at 600 gf), and the withstand power is 60 W. In addition, the boil coil 6 is for convenience of illustration,
Although only a part thereof is shown in FIG. 3B, as will be described later, each of the tops 7 a 1 to 7 a 7
Are tightly wound around the bottom of each.

The frame 1 is a frame formed of a heat-resistant resin such as a super heat-resistant ABS resin. The frame 1 is screwed and fixed to a speaker cabinet (not shown) via screw holes 1A to 1D provided at four corners thereof (the dimensions of the speaker cabinet are, for example, a thickness of 60 mm and a width of 1 mm).
20 mm, height 500 mm). A rear plate 2 is firmly screwed and fixed to the entire rear side of the frame 1, while four dampers 8 are adhesively fixed to four corners on the front side (diaphragm 7 side). The diaphragm 7 is formed by these four dampers 8.
The four corners are supported so as to freely vibrate.

The rear plate 2 is formed of a metal plate such as iron, and is a base plate for fixing the longitudinal magnets 3 having the longitudinal pole pieces 4 adhered to the upper surface thereof. A large number of air vent slits / holes are provided on the entire rear side of the rear plate 2 and a pair of speaker terminals connected to the start and end of the boil coil 6 are provided (neither is shown). On the other hand, both ends of the long pole piece 4 to which the long magnet 3 is adhered are screwed and fixed with the guide pins 5 on the front side (the diaphragm 7 side) of the rear plate 2 as described above. In the illustrated example, seven longitudinal magnets 3 are provided in parallel with each other.

The magnet 3 is a magnet obtained by sintering ferrite such as strontium ferrite. As described above, when this magnet 3 is fixed to the front side (diaphragm 7 side) of the rear plate 2, one surface of the magnet 3 in contact with the rear plate 2 becomes the N pole, while the magnet 3 in contact with the pole piece 4. The magnet 3 is magnetized so that the other surface (the diaphragm 7 side) of the magnet 3 becomes an S pole. The dimensions of the magnet 3 are, for example, 80 mm in length, 5 mm in width, and 8 mm in thickness.

The pole piece 4 is made of a metal plate such as iron, and has a pair of screw holes at both ends for fixing the magnet 3 to the rear plate 2. The boil coil 6 is provided with top portions 7a1 to 7a7 constituting the diaphragm 7.
Is a coated copper wire sequentially wound around each. As described above, the start and end (not shown) of the boil coil 6 are connected to a pair of speaker terminals provided on the rear plate 2 respectively. The details of winding the boil coil 6 around the tops 7a1 to 7a7 constituting the diaphragm 7 will be described later.

The diaphragm (diaphragm) 7 is made of a polyimide (PI) film that withstands heat generated by the boiler coil 6 and has excellent mechanical properties as a diaphragm, and is integrally molded. Also, in order to reduce the weight of the diaphragm 7,
Although it is necessary to make the diaphragm itself as thin as possible, the thickness of the diaphragm 7 used here was 75 μm. As described above, the diaphragm 7 is mounted on the magnet 3 and the pole piece 4 fixed on the rear plate 2, and the periphery thereof is positioned and fixed to the frame 1 by an edge 9 made of urethane or the like.

The damper 8 supports the vibration plate 7 so as to be able to vibrate freely, and is made of a thermoplastic resin such as polycarbonate, which is a material having high spring properties, impact resistance and heat resistance. In order to obtain a maximum amplitude of 10 mmpp in a limited space, a multi-stage leaf spring structure is used. Since the dampers 8 are fixed to the four corners of the frame 1, the displacement of each damper 8 is 150 gf and the displacement is 10 mm pp. This load is supported by a four-end support beam structure. Further, the structure is such that the tensile load in the plane direction of the diaphragm 7 is received by the connecting portion at the center of the damper 8. The beam structure is arranged in a fan shape to save space.

The above-mentioned diaphragm 7 is shown in FIG.
(B) As shown in FIG.
a7, a flat portion 7b, and an outer peripheral portion 7c. These top portions 7a1 to 7a7, the flat portion 7b, and the outer peripheral portion 7c are integrally formed. The top portions 7a1 to 7a7 are formed in a curved convex shape (bulge) from the back side (the rear plate 2 side) of the vibrating plate 7 toward the front side. Here, the front side of the vibrating plate 7 is the front side of the thin speaker unit A driven entirely. The tops 7a1 to 7a7 are in the longitudinal direction of the diaphragm 7 (FIG. 3A,
In FIG. 4 (A), seven are arranged in parallel in the vertical direction.
The cross-sectional shape of each of the tops 7a1 to 7a7 is shown in FIG.
It has a convex shape (kamaboko shape, semi-cylindrical shape) cut along the line AA '. An outer peripheral portion 7c is formed around the main vibrating portion 7A.

By supplying an audio signal (driving current) between the pair of speaker terminals of the thin speaker unit A having the above-described configuration, the tops 7a1 to 7a7 of the diaphragm 7 move relative to the paper surface. The whole surface vibrates uniformly before and after.

[0012]

As described above, each of the top portions 7a1 to 7a7 arranged in parallel on the diaphragm 7 as described above.
When a driving current is supplied to the voice coil 6 wound around the head portions 7a1 to 7a7, there is a difference in the driving force between the vicinity of both ends 7aa and 7ab and the vicinity of the center 7ac. As a result, the top portion 7a1 is used as the main vibrating portion 7A.
7a7 do not vibrate integrally. That is, the tops 7a1-7
In a7, split vibration (split resonance) occurs independently.

As a result, as shown in FIG. 5, the characteristic A of the conventional full-drive thin speaker unit A has a dip of 40 dB at the maximum in the middle band (about 800 Hz to about 4 kHz). And the level fluctuation is much larger than other ranges. For this,
Flat sound pressure frequency characteristics could not be obtained in the mid range.

In order to solve the problem that a flat sound pressure cannot be obtained in the entire frequency band, the present invention particularly comprises a plurality of divided portions in the direction orthogonal to the longitudinal direction of each crest. Accordingly, it is an object to provide an electroacoustic transducer capable of obtaining a flat sound pressure in all frequency bands by integrally vibrating a top portion as a main vibrating portion.

[0015]

In order to solve the above-mentioned problems, the present invention provides an electro-acoustic transducer having the following constitutions (1) to (4).

(1) As shown in FIGS. 1, 2 and 6,
Electroacoustic transducers (entirely driven thin loudspeaker units) AA and BB that drive the flat diaphragms 70 and 700 over the entire surface, and include a plurality of elongated protrusions (tops) 70a1 to 70a
a7, 700a1 to 700a5 are arranged in parallel, and the protrusions (tops) 70a1 to 70a7, 700a
1 to 700a5 are divided parts T1 to T5, U1 to U5, V1 to V divided into a plurality in a direction orthogonal to the longitudinal direction.
5, W1-W5, X1-X5, Y1-Y5, Z1-Z
5, T10 to T90, U10 to U90, V10 to V9
An electroacoustic transducer comprising: 0, W10 to W90, and X10 to X90.

(2) The electroacoustic transducer according to (1), wherein the adjacent divided portions T1 to T5, U1 to U
5, V1 to V5, W1 to W5, X1 to X5, Y1 to Y
5, Z1 to Z5, T10 to T90, U10 to U90, V
An electroacoustic transducer, wherein the shapes of 10 to V90, W10 to W90, and X10 to X90 are shapes complementary to each other (concave and convex shapes).

(3) The electroacoustic transducer according to the above (1) or (2), wherein the projections (tops) 70a1 to 70a1
70a7, the number of 700a1 to 700a5, and the divided portions T1 to T5, U1 to U5, V1 to V5, W1 to W5,
X1 to X5, Y1 to Y5, Z1 to Z5, T10 to T9
0, U10 to U90, V10 to V90, W10 to W9
An electroacoustic transducer, wherein the numbers 0, X10 to X90 are all odd numbers.

(4) As shown in FIG. 6, the electro-acoustic transducer described in (3) above (a thin speaker unit driven entirely).
BB, the protrusions (tops) 700a1 to 700a
The number of 0a5 is 5, the divided portions T10 to T90, U10
~ U90, V10-V90, W10-W90, X10
An electroacoustic transducer, wherein the number of X90 is nine.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an electroacoustic transducer according to the present invention will be described in order of first and second embodiments with reference to the drawings. FIGS. 1 and 6 are diagrams for explaining first and second embodiments of the electro-acoustic transducer of the present invention, respectively.
FIG. 1 is a front view of the electroacoustic transducer, FIG. 2B is a right side sectional view of the electroacoustic transducer, and FIG. FIG.
FIG. 2A is a front view of the diaphragm, and FIG.
A longitudinal section taken along the line -A ', FIG.
It is a longitudinal section taken along line -B '. FIG. 7 is a diagram for explaining a damper constituting the electro-acoustic transducer of the present invention. The same components as those described above are denoted by the same reference numerals, and description thereof will be omitted.

(1) First Embodiment of the Present Invention (Fully Driven Thin Speaker Unit AA) The first embodiment of the electroacoustic transducer of the present invention is a fully driven thin speaker unit AA shown in FIGS. The configuration of the speaker unit A is almost the same as that of the speaker unit A shown in FIG. 4, particularly, the configuration of the diaphragm is merely changed, and the other configuration is the same as that of the conventional one. In the following description, only this diaphragm will be described. Specifically, the diaphragm 70 is formed by dividing the tops 7a1 to 7a7 of the diaphragm 7 shown in FIGS. 3 and 4 into the dividing lines a1 to a7, b serving as nodes in a direction orthogonal to the longitudinal direction.
These are almost the same as those divided into a plurality of parts 1 to b7, c1 to c7, and d1 to d7.

[0022] Fully driven thin speaker unit A of the present invention
As shown in FIG. 1, A includes a frame 1, a rear plate 2, a magnet 3, a pole piece 4, a guide pin 5, a boil coil 6, a diaphragm (diaphragm) 70, a damper 8, and an edge 9.

In FIG. 2, the diaphragm 70 has a plurality of longitudinal top portions 70a1 to 70a formed in the longitudinal direction in the vertical direction.
7, a flat portion 70b, and an outer peripheral portion 70c.
c is integrally molded. In the figure, the tops 70a1 to 70a
Although a7 is integrally formed on the diaphragm 70, it is needless to say that the number of the tops can be appropriately changed as needed to obtain desired characteristics. For example, the number at the top may be an odd number (5, 7, 9, 11).

The top portions 70a1 to 70a7 are divided in the direction (horizontal direction in FIG. 2) perpendicular to the longitudinal direction thereof into dividing lines a1 to a7, b1 to b7, c1 to c7, d1 to d7.
Is divided into five. These division lines a1 to a7, b1 to b
7, c1 to c7 and d1 to d7 are not simple linear shapes, but are line recesses (or rib-like lines) formed by pressing and molding the tops 70a1 to 70a7. These are ribs, which increase the rigidity. Although the number of the dividing lines is four in the lateral direction of the tops 70a1 to 70a7, it is needless to say that the dividing lines can be appropriately changed as needed in order to obtain desired characteristics. For example, the number of dividing lines may be an even number (2, 4, 6, 8, 10, 12).

Specifically, the top 70a1 is divided by a dividing line a
1, 1, b 1, c 1 and d 1 are divided into divided portions T 1 to T 5. Similarly, the top 70a2 is divided by dividing lines a2, b2, c
2, d2, is divided into divided parts U1 to U5,
a3 is a dividing line a3, b3, c3, d3 and a divided portion V1.
V5, and the top 70a4 is divided into dividing lines a4, b4,
Divided into divided portions W1 to W5 at c4 and d4,
0a5 is a division line X5 with division lines a5, b5, c5, and d5.
To X5, and the top 70a6 is divided into dividing lines a6, b
6, c6, and d6, and the top 70a7 is divided into divisions Z1 to Z5 by division lines a7, b7, c7, and d7. When these divided portions are attached to the damper 8, the top portions 70a1 to 70a7
T1, U at both ends 70aa, 70ab
1, V1, W1, X1, Y1, Z1, T5, U5, V
5, W5, X5, Y5 and Z5 are preferably convex. Also,
The divided portions T3, U3, V3, W3, X3, Y3, and Z3 in the central portion 70ac of the top portions 70a1 to 70a7 are also preferably convex. The reason is that the tops 70a1 to 70a7
Is to be divided into odd numbers.

The above dividing lines a1 to a7, b1 to b7,
The intervals of c1 to c7 and d1 to d7 are equal as shown in FIGS. 1 and 2, but it is a matter of course that the intervals can be appropriately set as needed in order to obtain desired characteristics.
The dividing lines a1 to a7, b1 to b7, c1 to c7, d
Equalizing the distances 1 to d7 is also advantageous in manufacturing a mold for the diaphragm 70, but it is only necessary to ensure rigidity without making the distances equal.

Of the divided parts T1 to Z5 constituting the above-mentioned tops 70a1 to 70a7, divided parts T1, T3,
T5, U1, U3, U5, V1, V3, V5, W1, W
3, W5, X1, X3, X5, Y1, Y3, Y5, Z
1, Z3, Z5 are formed in a semi-cylindrical shape (semi-cylindrical shape, convex shape) on the plane portion 70b, and the cross-sectional shape thereof is taken along the line AA ′ shown in FIG. 2 (B). It is a cross-sectional shape.

On the other hand, of the divided portions T1 to Z5 forming the top portions 70a1 to 70a7, the divided portions T2, T4, U
2, U4, V2, V4, W2, W4, X2, X4, Y
2, Y4, Z2, and Z4 are formed on the plane portion 70b in a curved shape (a shape opposite to the top of the kamaboko shape, a concave shape) that is a shape complementary to the kamaboko shape described above,
The cross-sectional shape is a cross-sectional shape taken along the line BB 'shown in FIG. As described above, since the adjacent divided portions are shaped into shapes complementary to each other (for example, between the divided portions T1 and T2, T5), the top portions 70a1 to 70a1 are formed.
Since the mechanical strength (rigidity) is increased with respect to the force applied perpendicularly to the longitudinal direction of 70a7 (or the force perpendicular to the longitudinal direction), the adjacent divided portions do not vibrate together, and one of them does not vibrate. When a larger or smaller vibration is to be started, the generation of the vibration component can be prevented beforehand.

As a result, in the divided portions T1 to Z5 forming the tops 70a1 to 70a7, the divided portions in the shape of a semicircle and the curved portions are alternately arranged adjacent to each other in the longitudinal direction. The top portions 70a1 to 70a7 form a main vibrating portion 70A. Four peripheral portions 70c are formed on the four circumferences of the main vibrating portion 70A. The diaphragm 70 having such a configuration is a film having a thickness of about 10 μm to 100 μm of a synthetic resin whose hardness is not relatively affected by temperature such as polyether, polyethylene, and polypropylene, or a composite film in which a plurality of such films are stacked. May be formed.

As a result, as shown in FIG. 5, the fully driven thin speaker unit AA of the present invention has a characteristic B in which the sound pressure is suppressed to a maximum of 20 dB in the middle band (about 800 Hz to about 4 kHz). Can be. As a result, the dip could be improved by about half compared with the characteristic A of the conventional speaker unit A described above. As a result, a flatter sound pressure frequency characteristic can be obtained in the middle band, and a flat sound pressure can be obtained in the entire frequency band.

(2) Second Embodiment of the Present Invention (Fully-Driven Thin Speaker Unit BB) A full-drive thin speaker unit BB as a second embodiment of the electroacoustic transducer of the present invention is shown in FIG. Fully driven thin speaker unit A according to the first embodiment of the present invention
A has substantially the same configuration as that of A. In particular, the only configuration is that the shapes of the diaphragm and the damper are changed, and other configurations have the same configuration as that of the overall-drive thin speaker unit AA. In the following description, the diaphragm 700 and the damper 80 will be mainly described.

The thin speaker unit B according to the present invention which is driven entirely.
6B, as shown in FIG. 6, a frame 10 having the same configuration as the frame 1 and having screw holes 10A to 10D, a rear plate 20 having the same configuration as the rear plate 2, a magnet 3, and a pole piece 4. , Guide pin 5, boil coil 6, diaphragm (diaphragm) 700, damper 8
0, edge 9 (for convenience of illustration, magnet 3, pole piece 4, and guide pin 5 are not shown). The same components as those described above are denoted by the same reference numerals, and description thereof will be omitted.

The vibrating plate 700 has seven top portions 70a1 to 70a of the vibrating plate 70 shown in FIGS.
7, five top portions 700a1 to 70a
0a5 is divided into eight dividing lines a10 to a50, b10 serving as nodes in a direction orthogonal to the longitudinal direction (vertical direction in FIG. 6).
~ B50, c10 ~ c50, d10 ~ d50, e10 ~
e50, f10 to f50, g10 to g50, h10 to h
50 is a plurality of divisions (9 divisions).

The vibration plate 700 has the same configuration as the vibration plates 7 and 70 described above. That is, a polyimide (PI) film that withstands the heat generated by the boil coil 6 and has excellent mechanical properties as a diaphragm is used and integrally formed. Further, in order to reduce the weight of the diaphragm 700, it is necessary to make the diaphragm itself as thin as possible. However, the thickness of the diaphragm 700 used here is set to 75 μm.
The vibration plate 700 is mounted on the magnet 3 and the pole piece 4 fixed on the rear plate 20, and the periphery thereof is positioned and fixed on the frame 10 by the edge 9 made of urethane or the like.

The diaphragm 700 has a plurality of longitudinal top portions 700a1 to 700a7 which are formed in the longitudinal direction in the vertical direction in FIG.
00a5, a flat portion 700b, and an outer peripheral portion 700c.
0b and the outer peripheral portion 700c are integrally molded. In the figure, the tops 700a1 to 700a5 are integrally formed on the diaphragm 700, and the number is five.

The tops 700a1 to 700a5 are formed by dividing lines a10 to a50, b10 to b50, c10 to c which are nodes in a direction (horizontal direction in FIG. 6) orthogonal to the longitudinal direction.
50, d10 to d50, e10 to e50, f10 to f5
0, g10 to g50, and h10 to h50 are respectively divided into nine. The dividing lines a10 to a50, b10 to b5
0, c10 to c50, d10 to d50, e10 to e5
0, f10 to f50, g10 to g50, h10 to h50
Is not just a straight line,
a5 is a line concave portion (or a rib-like line) formed by pressing and forming a concave or convex rib with a narrow width, thereby increasing rigidity. The number of these dividing lines is the summit 700a1 to 700a5
Are provided in the horizontal direction.

More specifically, the top 700a1 has eight dividing lines a10, b10, c10, d10, e10, f1.
At 0, g10, and h10, the image is divided into nine parts T10 to T90. Similarly, the top 700a2 has eight dividing lines a2.
0, b20, c20, d20, e20, f20, g2
At 0 and h20, the part is divided into nine parts U10 to U90, and the top 700a3 has eight dividing lines a30, b30, and c3.
0, d30, e30, f30, g30, h30 are divided into nine parts V10 to V90, and the top 700a4 is divided into eight parts.
Book dividing lines a40, b40, c40, d40, e40,
At f40, g40 and h40, the divided parts W10 to W90 are set to 9
Is divided, and the top 700a5 has eight dividing lines a
50, b50, c50, d50, e50, f50, g5
At 0 and h50, the image is divided into nine parts X10 to X90.
When these divided portions are attached to the damper 80, the divided portions T10, T10, at both ends of the tops 700a1 to 700a5.
U10, V10, W10, X10, T90, U90, V
90, W90 and X90 are preferably convex. Also, a divided portion T5 at the center of the tops 700a1 to 700a5
0, U50, V50, W50 and X50 are also preferably convex. The reason for this is that the tops 700a1 to 700a5 are each divided into odd numbers.

The above dividing line a10-b10-c10-
Each interval of d10-e10-f10-g10-h10, dividing line a20-b20-c20-d20-e20-f20
-G20-h20 intervals, dividing lines a30-b30-c
Each interval of 30-d30-e30-f30-g30-h30, dividing line a40-b40-c40-d40-e40-
Each interval of f40-g40-h40, dividing line a50-b5
0-c50-d50-e50-f50-g50-h50
The intervals are equal as shown in FIG. 6, but it is a matter of course that the intervals can be appropriately set as needed in order to obtain desired characteristics. As described above, equalizing the interval between adjacent dividing lines is advantageous in manufacturing a mold for the diaphragm 700. However, even if the interval is not equal, rigidity may be ensured. .

Of the divided parts T10 to X90 constituting the above-mentioned tops 700a1 to 700a5, the divided part T1
0, T30, T50, T70, T90, U10, U3
0, U50, U70, U90, V10, V30, V5
0, V70, V90, W10, W30, W50, W7
0, W90, X10, X30, X50, X70, X90
Is semi-cylindrical (semi-cylindrical, convex) on the flat part 700b
And the cross-sectional shape thereof is the same as that of the above-described divided portions T1, T3, T5, U1, U3, U5, V1, V
3, V5, W1, W3, W5, X1, X3, X5, Y
1, Y3, Y5, Z1, Z3, and Z5 have the same cross-sectional shape as the AA 'line shown in FIG. 2B.

On the other hand, the above-mentioned tops 700a1 to 700a
Among the divided parts T10 to X90 constituting the a5, the divided parts T20, T40, T60, T80, U20, U40,
U60, U80, V20, V40, V60, V80, W
20, W40, W60, W80, X20, X40, X6
0, X80 are formed on the flat portion 700b in a curved shape (a shape opposite to the top of the Kamaboko shape, concave shape) that is complementary to the above Kamaboko shape, and have a cross-section thereof. The shape is the above-mentioned divided part T2, T4, U2, U
4, V2, V4, W2, W4, X2, X4, Y2, Y
4, Z2, and Z4 have the same shape as the cross-sectional shape taken along the line BB 'shown in FIG. As described above, since the adjacent divided portions are shaped into complementary shapes to each other, the mechanical force is not applied to the force applied perpendicularly to the longitudinal direction of the tops 700a1 to 700a5 (or the force perpendicular to the longitudinal direction). Since the target strength (rigidity) increases, when one of the divided portions starts to vibrate larger or smaller than the other without the adjacent divided portions vibrating together, the generation of the vibration component is complementarily performed. It can be prevented beforehand.

As a result, the tops 700a1 to 700a5
In the divided portions T10 to X90, the divided portions in the shape of a kamaboko and the divided portions in a curved shape are alternately arranged adjacent to each other in the longitudinal direction. These tops 700a1
700a5 forms the main vibration part 700A. Four peripheral portions 700c are formed on four sides of the main vibrating portion 700A. In the diaphragm 700 having such a configuration, the thickness of a synthetic resin whose hardness is not relatively affected by the temperature of polyether, polyethylene, polypropylene or the like is 10 μm to 100 μm.
It may be formed from a member such as a composite film in which about m films or a plurality of such films are overlapped.

By the way, the above-described damper 80 uses the edge 9 to make the frame 1 similar to the above-described damper 8.
Vibrating plate 7 whose entire periphery is firmly adhered and fixed within 0
00 is supported (locked) in the frame 10 so as to be able to vibrate freely, and is made of a thermoplastic resin such as polycarbonate which is a material having high spring properties, impact resistance and heat resistance. Maximum amplitude 10mmpp in limited space
In order to obtain the above structure, a leaf spring structure and a support beam structure at both ends are provided, and one pair (two) of the dampers 80 (using the dampers 80A and 80B) are used to form upper and lower sides of the frame 10 and both ends thereof. The upper and lower sides of the diaphragm 700 and both ends thereof (in FIG. 6, the upper and lower sides of the diaphragm 700 and the left and right sides thereof) (Both ends) can be reliably locked and supported together. For each damper 80 (dampers 80A, 80B), a displacement of 10 mmp-p is obtained at 150 gf. Furthermore, the tensile load in the plane direction of the diaphragm 700 is
0 (damper 80A, 80B) is a structure to be covered by a connecting portion at the center. In addition to the above, the damper 80 can be formed of a soft member such as foamed plastic, cloth sealed with plastic, or a metal member.

The above-described damper 80 (80A, 80B)
As shown in FIG. 7, the structure of the frame mounting portion 80a,
Four spring portions 80b1, 80b2, 80c1, 80c
2. It is composed of a diaphragm locking part 80d and a connecting part 80e. The frame attachment portion 80a is a U-shaped frame that is locked to the upper side and the lower side of the frame 10, respectively. The frame mounting portion 80a connects and locks one end of each of the two spring portions 80b1 and one end of each of the two spring portions 80b2. The diaphragm locking portion 80d is locked to the upper side and the lower side of the diaphragm 700, respectively. The diaphragm locking portion 80d is composed of two spring portions 8
0c1 and one end of the two spring portions 80c2 are connected and locked. The connecting portion 80e is connected to the other ends of the two spring portions 80b1 and the other ends of the two spring portions 80b2, and the other ends of the two spring portions 80c1 and the two spring portions 8c.
0c2 is connected to each other end. In addition, the above-described spring portion 80
b1, 80b2, 80c1, and 80c2 are thinner than the thicknesses of the frame mounting portion 80a, the diaphragm locking portion 80d, and the connecting portion 80e. As a result, the frame mounting portions 80a,
Since a two-stage leaf spring structure is generated between the diaphragm locking portion 80d and the connecting portion 80e, the diaphragm locking portion 80d can be freely displaced in the vibration direction of the diaphragm 700 by using the connecting portion 80e as a beam. This can be locked as possible.
As described above, the frame mounting portion 80a and the spring 8
0b1, 80b2, and the connecting portion 80e are connected to the damper 80 (8
0A, 80B). On the other hand, the above-mentioned spring portions 80c1, 80c2,
The diaphragm locking portion 80d is provided with a damper 80 (80A, 80A).
B) constitutes the first locking portion 80aa.

The above-mentioned diaphragm locking portion 80d is
There are provided reverse arcuate locking portions 80d1 to 80d5 for locking the lower edges of the top portions 700a1 to 700a5 of the 00 arc shape. The inverted arc-shaped locking portions 80d1 to 80d5 are integrally supported by the support portion 80d6. As described above, the damper 80 having such a configuration is provided with the frame mounting portion 8.
0a, the diaphragm locking portion 80d, and the connecting portion 80e, a two-stage leaf spring structure is generated.
Can be used as a beam so that the diaphragm locking portion 80d can be freely displaced in the vibration direction of the diaphragm 700.

As described above, the upper and lower sides of the frame 10 and both ends thereof (the frame 10 in FIG. 6) are different from the conventional damper 80 using four dampers 8 as described above. The diaphragm 700 can be securely locked and supported on both the upper and lower sides and the left and right ends thereof.

As a result, the rigidity of the diaphragm 700 in the width direction (vertical direction in FIG. 6) is further increased, and the diaphragm in the width direction (horizontal direction in FIG. 6) is improved. Since the divided vibration of 700 is further reduced, the top portions 700a1 arranged in parallel on the diaphragm 700 are compared with the thin speaker units A and AA which are driven on the whole surface.
When a driving current is supplied to the voice coil 6 wound around the tops 700a5 to 700a5, the difference in driving force between the vicinity of both ends of the tops 700a1 to 700a5 and the vicinity of the center thereof is almost eliminated. It will vibrate together. That is, the tops 700a1 to 70a
0a5 does not cause any split vibration (split resonance) at any place on the diaphragm 700,
A sound with the same phase can be output in a planar manner. Accordingly, the full-drive thin speaker unit BB can reproduce the high-frequency component in the sound pressure frequency characteristics of the above-described full-drive thin speaker unit AA with good S / N.

[0047]

According to the electro-acoustic transducer of the present invention having the above-described structure, since the driving force of the diaphragm becomes uniform over the entire surface, undesired vibrations such as split vibrations can be prevented. Flat sound pressure can be obtained in the frequency band. In addition, since the rigidity of the diaphragm in the width direction is further increased and the divided vibration in the width direction is further reduced, the driving force at the center and both ends of the diaphragm can be substantially uniform. The whole plate is vibrated integrally. As a result, a sound having the same phase can be output in a planar manner in any part of the diaphragm, whereby the high frequency component in the sound pressure frequency characteristic can be further reduced by S.
/ N can be reproduced well.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a first embodiment of an electroacoustic transducer of the present invention.

FIG. 2 is a diagram for explaining a diaphragm constituting a first embodiment of the electroacoustic transducer of the present invention.

FIG. 3 is a diagram for explaining a conventional electroacoustic transducer.

FIG. 4 is a diagram for explaining a diaphragm constituting the electroacoustic transducer.

FIG. 5 is a diagram comparing sound pressure frequency characteristics of an electroacoustic transducer of the present invention with sound pressure frequency characteristics of a conventional electroacoustic transducer.

FIG. 6 is a diagram for explaining a second embodiment of the electro-acoustic transducer of the present invention.

FIG. 7 is a diagram for explaining a damper constituting the electro-acoustic transducer of the present invention.

[Explanation of symbols]

1,10 frame (frame body) 7,700 diaphragm 7a1-7a7, 70a1-70a7, 700a1-7
00a5 Top (projection) 8, 80, 80A, 80B Damper 80aa, 80ab First and second locking portions 80d Diaphragm locking portions 80d1 to 80d5 Reverse arc-shaped locking portions A, AA, BB Speaker unit (electroacoustic transducer) a1 to a7, b1 to b7, c1 to c7, d1 to d7, a
10 to a50, b10 to b50, c10 to c50, d1
0 to d50, e10 to e50, f10 to f50, g10
To g50, h10 to h50 Parting lines U1 to U5, V1 to V5, W1 to W5, X1 to X5, Y
1 to Y5, Z1 to Z5, T10 to T90, U10 to U9
0, V10 to V90, W10 to W90, X10 to X90
Split part

Claims (4)

[Claims] 1. An electro-acoustic transducer for driving a flat plate-like diaphragm entirely, wherein a plurality of elongated protrusions are arranged in parallel, and the plurality of protrusions are arranged in a direction orthogonal to the longitudinal direction. An electro-acoustic transducer comprising a divided part divided into a plurality of parts. 2. The electro-acoustic transducer according to claim 1, wherein the adjacent divided portions have shapes complementary to each other. 3. The electroacoustic transducer according to claim 1, wherein the number of the projections and the number of the divided portions are both odd numbers. 4. The electroacoustic transducer according to claim 3, wherein the number of the protrusions is five and the number of the divided parts is nine.