JP2001333492A - Ribbon speaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ribbon speaker that can accurately restrict the moving range of a ribbon diaphragm with a simple configuration so as to reduce the manufacture cost. SOLUTION: The ribbon speaker is provided with a support plate 11 made of an aluminum flat plate having a square hole 10 in the middle, the ribbon diaphragm 13 that is placed with an interval from long-side circumferential edge parts 10a of the square hole 10 and has lead wires 12 for supplying a drive current are soldered to both ends, and a damping member 14 that is made of an nonwoven fabric on both sides of the support plate 11 to cover the ribbon diaphragm 13. The moving range of the ribbon diaphragm 13 is accurately restricted by the damping member 14 and wool of the nonwoven fabric is in contact with a vibration section 13d to prevent parasitic vibration of the ribbon diaphragm 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ribbon loudspeaker, and more particularly to a structure of a ribbon loudspeaker having an ultra-high frequency characteristic corresponding to a required frequency characteristic in DVD audio.

[0002]

2. Description of the Related Art DVD audio has been put to practical use as a new music optical disk that can replace the existing CD (Compact Disc). Generally, audio data recorded on a CD has a maximum sampling frequency of 44.1 kHz and a maximum sampling frequency of 164.1 kHz.
This is audio data quantized at a bit resolution. CDs have the advantage that they are easier to handle and store than previous analog records, but they are said to be inferior to analog records in terms of sound quality. The sound range that can be actually heard by humans may be 20 kHz or more, and the dynamic range needs to be 120 dB or more. DVD audio, on the other hand, has a linear PCM
The coding method is adopted, but the maximum sampling frequency is 19
By increasing the resolution to 24 bits and increasing the resolution to 24 bits, 120 dB can be achieved within the response frequency band up to 96 kHz.
Dynamic range can be maintained.

[0003] A reproducing apparatus for reproducing DVD audio includes:
In addition to expanding the frequency characteristics of the amplifier, which is a circuit system, to the ultra-high frequency range to take advantage of DVD audio,
A speaker corresponding to the acoustic system is also required to have a corresponding characteristic. As is well known, there are two types of speakers: a woofer that plays the low and middle frequency ranges, and a tweeter that plays the high frequency range.
In order to bring out the advantages of DVD audio, it is particularly important to improve the characteristics of the tweeter, that is, to increase the tweeter's ultra-high frequency range.

In general, an electro-dynamic cone loudspeaker has a disk-shaped bottom yoke formed of a magnetic metal member having a cylindrical pole portion in the center, and an annular magnet is mounted on the bottom yoke to form a magnetic circuit. In this configuration, a coil bobbin around which a voice coil fixed to the center of a diaphragm suspended by an edge and a damper on a frame is inserted into a pole portion forming a magnetic circuit. When a driving current is supplied to the voice coil, the diaphragm vibrates in the front-back direction of the speaker, and is converted from an electric signal into air vibration (acoustic signal). The response characteristics of the speaker are greatly affected by the size and material of the diaphragm and the damper material used for fixing the diaphragm to the frame. Especially for high frequency speakers,
A structure in which the diaphragm is held by the damper cannot be used.

In order to vibrate the diaphragm at a high frequency, it is necessary to reduce the weight of the diaphragm itself. However, dampers, voice coils, coil bobbins, and the like are components that hinder the reduction in the weight of the diaphragm. There is a ribbon speaker as a high-range speaker that solves these problems.

[0006] As shown in FIG.
A ribbon 3 made of metal foil is placed in a magnetic field generated by the north and south poles of the two magnetic poles 1 and 2, and a current is directly supplied to the ribbon 3 to generate a force on the ribbon 3 according to Fleming's left-hand rule. This is a speaker that vibrates the ribbon 3 according to the drive current. That is, since the ribbon speaker itself has the functions of the diaphragm and the voice coil, the coil bobbin is not required, and the diaphragm can be reduced in size and weight, and is suitable for a high-range speaker.

In the ribbon speaker, since the ribbon 3 is disposed adjacent to the two magnetic poles 1 and 2, the ribbon speaker is conventionally provided with a gap between both side surfaces of the ribbon 3 and the adjacent magnetic poles 1 and 2 as shown in FIG. The support and movement range of the ribbon 3 are regulated by injecting and bonding the gel-like silicon 4 and using the cured silicon 4 as a damper material. However, since the characteristics of the ribbon speaker having such a structure are different depending on the amount of silicon 4 and the position where the ribbon 4 is fixed, high precision work is required in the sealing process of silicon 4, reliability and yield are poor, and manufacturing cost is high. Had become a factor.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object the purpose of being able to accurately regulate the moving range of a ribbon diaphragm with a simple configuration, and to reduce manufacturing costs. It is to provide a ribbon speaker that can be suppressed.

[0009]

According to a first aspect of the present invention, there is provided a ribbon speaker, wherein both ends of a ribbon diaphragm are fixed to a support plate, and both sides of the support plate have air permeability. And a pair of braking members.

A ribbon speaker according to a second aspect of the present invention is the ribbon speaker according to the first aspect, wherein the damping material is made of a nonwoven fabric.

According to a third aspect of the present invention, there is provided a ribbon speaker according to the first or second aspect, wherein the damping member is arranged to be in contact with the ribbon diaphragm.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the main structure of a ribbon speaker according to an embodiment of the present invention will be described below with reference to FIG. FIGS. 1 and 2 are views showing a support mechanism of the ribbon diaphragm. FIG. 1 is a plan view of the ribbon diaphragm support mechanism with a part of a braking member 14 to be described later removed. 2 shows a side view of the ribbon diaphragm support mechanism.

A ribbon vibration plate support mechanism 20 according to an embodiment of the present invention includes a support plate 11 formed of an aluminum flat plate having a square hole 10 in the center and a long side inner peripheral portion 1 of the rectangular hole 10.
And a ribbon vibration plate 13 to which lead wires 12 for supplying a drive current are soldered to both ends, and a cloth is provided on both sides of the support plate 11 so as to cover the ribbon vibration plate 13 without weaving fibers. The braking member 14 formed of a non-woven fabric with good air permeability generated in a shape is arranged. The nonwoven fabric in this embodiment is made of nylon, has a thickness of 0.16 mm, and has a basis weight of 20 gm 2.

Next, the support plate 11 and the ribbon diaphragm 1
3 will be described in detail with reference to FIGS. still,
3 and 4 are structural views of the support plate 11, wherein FIG. 3 is a plan view of the support plate 11, and FIG. 4 is a partially enlarged view of the support plate 11. 5 and 6 are structural diagrams of the ribbon diaphragm 13. FIG. 5 is a plan view of the ribbon diaphragm 13 and FIG. 6 is a side view of the ribbon diaphragm 13.

Support plate 11 for supporting ribbon diaphragm 13
As shown in FIGS. 3 and 4, is a rectangular aluminum flat plate having a thickness of about 0.3 mm provided with an insulating film by anodizing, and a short side 10b for accommodating the ribbon diaphragm 13 in the center.
Is formed with a square hole 10 of about 4.8 mm, an adhesive 11a is applied to one surface, and a separator 11b protects the adhesive 11a.

The ribbon diaphragm 13 has a width of about 4.2 m.
m and a band-shaped aluminum foil having a thickness of about 9 μm. At the time of assembling the ribbon speaker 20 to be described later, a portion located in the square hole 10 of the support plate 11 by using a rolling jig (not shown) is shown in FIG. As shown in FIG. 6, a mountain-shaped uneven portion 13 b is formed at the center, and square holes 1 are formed on both sides of the ribbon diaphragm 13.
A U-shaped bent portion 13c is formed at a portion located inside the short side 10b of the zero. Uneven portion 13b of ribbon diaphragm 13
Is formed to be thinner than the thickness of the support plate 11 to form a vibrating portion 13d which prevents undulation of the ribbon vibrating plate 13 in the rectangular hole 10 and has increased strength.
Has an edge function and facilitates the vibration of the ribbon diaphragm 13 in the square hole 10.

Next, a method of assembling the ribbon diaphragm supporting mechanism 20 according to the present embodiment will be described with reference to FIGS. FIG. 7 is a perspective view in which a part of the ribbon diaphragm supporting mechanism 20 is enlarged, and the positional relationship between the support plate 11, the ribbon diaphragm 13 and the braking member 14 is shown in an easy-to-understand manner.

First, the separator 11b of the support plate 11 is peeled off, and the belt-shaped ribbon vibration plate 13 is placed on the support plate 11 coated with the adhesive material 11a. Paste on top. At this time, the ribbon vibration plate 13 is placed so as to be positioned at the center of the short side 10b of the square hole 10 of the support plate 11, so that a gap is provided with the inner peripheral edge portion 10a of the long side of the square hole 10. . The support plate 2
Fixed portion 13 of ribbon diaphragm 13 protruding outside of
a cuts.

Next, both fixing portions 13a of the ribbon diaphragm 13
Preliminary soldering with aluminum solder is performed at a predetermined position in order to solder the lead wire 12. Then, the lead wire 12 is placed on the pre-soldered ribbon diaphragm 13 and the adhesive 1
After being fixed at 1a, it is soldered to the ribbon diaphragm 13. Since the insulating film is formed on the surface of the support plate 11 by the alumite treatment as described above, the drive current is supplied only to the ribbon vibration plate 13 via the lead wire 12.

Next, the support plate 11 and the ribbon vibrating plate 13 fixed to the support plate 11 are mounted on a rolling jig. As shown in FIG. 3, the rolling jig rolls the vibrating portion 13d and the bending portion 13b of the portion of the ribbon vibration plate 13 arranged in the square hole 10 of the support plate 11 as shown in FIG. Thus, the vibrating portion 13d of the ribbon diaphragm 13 is
Is supported in a state where it is housed in the square hole 10. Thereafter, a damping material 14 formed of a nonwoven fabric having air permeability is attached to the adhesive material 11a of the support plate 11. Finally, the braking member 14 is fixed to the other surface of the support plate 11 using, for example, a double-sided tape or the like, and the assembly operation of the ribbon diaphragm support mechanism 20 is completed.

As described above, the ribbon vibrating plate supporting mechanism 20 of the present embodiment is configured such that after the band-shaped ribbon vibrating plate 13 is fixed to the square hole 10 of the supporting plate 11, the vibrating portion 13d and the bending portion 13 Since the 13b is formed, high-precision work becomes possible, and stable characteristics are achieved by making the shape of the vibrating portion 13d and the bending portion 13b uniform and making the gap between the vibrating portion 13d and the long side inner peripheral edge portion 10a uniform. Is obtained, reliability and yield are improved, and manufacturing costs can be kept low. Further, since the structure can be made uniform, it is possible to obtain a ribbon speaker which is lighter in weight by using a thinner aluminum foil and has excellent super high frequency characteristics.

Further, according to the present embodiment, since the damping material 14 is provided on the support plate 11 so as to sandwich the ribbon vibration plate 13, the movement range of the vibration portion 13d can be regulated accurately. Also, by using a non-woven fabric for the braking material 14,
Since the fibers of the non-woven fabric can be configured to slightly contact the surface of the vibrating portion 13d, it is possible to suppress the occurrence of parasitic vibration generated within a predetermined frequency band due to the size and shape of the vibrating portion 13d. Next, a structure and an assembling method of the tweeter 50 using the ribbon diaphragm support mechanism 20 of the present embodiment will be described with reference to FIGS. FIG. 8 is a perspective view of the tweeter 50, and FIG. 9 is a cross-sectional view of the tweeter 50.

The tweeter 50 has a rectangular magnet 22 disposed in the center of the bottom case 21 and L-shaped magnets disposed on the left and right side surfaces of the magnet 22 to form a predetermined magnetic gap G on the top surface side of the magnet 22. And a magnetic gap G of the inner yoke 23
And a pair of L-shaped outer yokes 24 arranged in contact with the inner yoke 23 to form a magnetic gap G in the same manner as the inner yoke 23. And a front case 26 having a rectangular opening 25 formed in the center.

In assembling the tweeter 50, the magnet 22 is fixed to the center of the inside of the bottom case 21 with an adhesive or the like, and then a pair of internal yokes 23 are arranged on both sides of the magnet 22. Next, the ribbon speaker 20 is placed on the magnetic gap G formed by the pair of internal yokes 23. Then, a pair of outer yokes 24 are inserted into the gap between the bottom case 21 and the inner yoke 23, and the ribbon diaphragm supporting mechanism 20 is inserted.
Is sandwiched between the magnetic gaps G of the inner yoke 23 and the outer yoke 24, and the lead wire 12 is pulled out to cover the front case 26 from above and fixed to the bottom case 21 with screws (not shown) to complete the assembly. .

Next, the operation of the tweeter 50 will be described with reference to FIG. FIG. 10 is a partially enlarged view of the cross-sectional view of the tweeter 50 shown in FIG.

As shown in FIG. 10, the ribbon diaphragm supporting mechanism 20 is fixed between the inner yoke 23 and the outer yoke 24, and the ribbon diaphragm 13 is substantially at the center of the magnetic gap G between the inner yoke 23 and the outer yoke 24. Placed in

Now, the inner yoke 23 and the outer yoke 24
It is assumed that the magnetic poles N and S are arranged as shown in the drawing, and a magnetic flux is formed in the direction indicated by the dotted arrow in the drawing. Then, if a drive current is supplied from the lead wire 12 and a drive current flows from the near side to the far side of the drawing on the ribbon diaphragm 13, the vibrating portion 13 d of the ribbon diaphragm 13
It is driven in the direction indicated by arrow F in the figure. Assuming that a driving current flows from the back of the paper toward the front of the paper, the vibrating portion 13d of the ribbon vibration plate 13 is driven in the direction opposite to the arrow F in the drawing. That is, the ribbon diaphragm 13 is driven in accordance with the drive current supplied to the lead wire 12, converted from an electric signal to an acoustic signal, and sound is output from the opening 25 of the front case 26.

As described above, the ribbon loudspeaker according to the embodiment of the present invention is used so as to be sandwiched between the inner yoke 23 and the outer yoke 24 when forming the tweeter 50. However, the present invention is not limited to this. For example, the same effect can be obtained by using only the internal yoke 23.
In addition, although a nonwoven fabric is used as the damping material, the fiber is not limited to the nonwoven fabric as long as it has excellent air permeability.

[0029]

According to the present invention, it is possible to accurately regulate the moving range of the ribbon with a simple structure, and it is possible to provide a ribbon speaker excellent in manufacturing cost.

[Brief description of the drawings]

FIG. 1 is a plan view of a ribbon diaphragm support mechanism according to an embodiment of the present invention.

FIG. 2 is a side view of the ribbon diaphragm supporting mechanism according to the embodiment of the present invention.

FIG. 3 is a plan view of a support plate constituting the ribbon speaker of the embodiment.

FIG. 4 is a side view of a support plate constituting the ribbon speaker of the embodiment.

FIG. 5 is a plan view of a ribbon diaphragm constituting the ribbon speaker of the embodiment.

FIG. 6 is a side view of the ribbon diaphragm constituting the ribbon speaker of the embodiment.

FIG. 7 is an enlarged perspective view of a part of the ribbon diaphragm supporting mechanism of the embodiment.

FIG. 8 is a perspective view of a ribbon tweeter configured using the ribbon diaphragm support mechanism of the embodiment.

FIG. 9 is a cross-sectional view of a ribbon tweeter configured using the ribbon diaphragm support mechanism of the embodiment.

FIG. 10 is an operation explanatory diagram of a ribbon tweeter using the ribbon speaker of the embodiment.

FIG. 11 is an operation principle diagram of a ribbon speaker.

FIG. 12 is a configuration diagram of a ribbon speaker in a conventional example.

[Explanation of symbols]

 10. Square hole 11. Support plate 12. Lead wire 13. Ribbon diaphragm 14. Braking material 20. Ribbon diaphragm support mechanism

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shoichiro Terauchi 4-2610 Hanazono, Tokorozawa-shi, Saitama F-term in the Tokorozawa Plant of Pioneer Corporation (reference) 5D012 AA01 BA03 BA08 BC02 CA07 CA10 EA02 FA03 FA10 5D016 AA04 AA17 EC23 HA07

Claims (3)

[Claims] 1. A ribbon speaker, wherein both ends of a ribbon diaphragm are fixed to a support plate, and a pair of breathable dampers are arranged on both surfaces of the support plate. 2. The ribbon speaker according to claim 1, wherein the damping material is made of a non-woven fabric. 3. The ribbon speaker according to claim 1, wherein the damping member is arranged so as to contact the ribbon diaphragm.