阅读说明：本技术 扬声器用振动板 (Vibrating plate for loudspeaker ) 是由 八卷绅太郎 松村隆司 掘口实 于 2019-09-12 设计创作，主要内容包括：扬声器用振动板构成为：在形成于振动板主体的外周的锥部接合有环部件,在环部件或锥部的外周部接合有边缘的内周部,不需要改变振动板主体的形状即会提高刚性,即在不导致振动板主体的重量增加的情况下使刚性提高,防止高频段的声压降低。(The speaker diaphragm is configured to: a ring member is joined to a cone formed on the outer periphery of a diaphragm body, and an inner peripheral portion of a rim is joined to the ring member or the outer peripheral portion of the cone, whereby the rigidity is improved without changing the shape of the diaphragm body, that is, the rigidity is improved without increasing the weight of the diaphragm body, and the reduction of sound pressure in a high frequency band is prevented.)

1. A diaphragm for a speaker, characterized in that: the main body member of the speaker diaphragm includes a central cover portion and a cone portion formed on an outer periphery thereof, wherein a ring member is joined to the cone portion of the main body member, and an inner peripheral portion of a rim is joined to the ring member or an outer peripheral portion of the cone portion.

2. The diaphragm for a speaker according to claim 1, wherein:

the central cover portion has a dome shape, and the ring member is joined to the front or rear surface of the tapered portion, and has the same shape as the tapered portion.

3. The diaphragm for a speaker according to claim 1, wherein:

a diaphragm fixing ring is joined to an outer peripheral portion of the edge.

4. The diaphragm for a speaker according to claim 1, wherein:

the body member and the ring member are formed by adding a bio-cellulose and a carbon fiber to a slurry.

5. The diaphragm for a speaker according to claim 1, wherein:

the tapered portion to which the ring member is joined has a shape rising toward the front.

6. The diaphragm for a speaker according to claim 1, wherein:

the vibrating plate for the loudspeaker is used for earphones.

Technical Field

The present disclosure relates to a speaker diaphragm suitable for an earphone.

Background

Since a speaker itself used for the earphone is required to be small and thin in terms of wearing feeling and design, a diaphragm used for the earphone is also required to be thin.

As a result, the rigidity is reduced due to the restriction that the total height of the dome portion of the dome-shaped vibration plate must be reduced.

As a material of the diaphragm, various materials formed of synthetic polymers such as polyolefin and polyester, new materials, and the like are available, but at present, paper materials (cellulose) excellent in performance, cost, and the like are often used.

As described above, when the speaker is thinned, the diaphragm becomes almost flat, and it is difficult to ensure the rigidity of the diaphragm mainly made of cellulose in terms of shape, and split resonance occurs in the diaphragm. As shown in fig. 6, the following problem occurs due to the influence of the split resonance: a peak or a trough (peak or trough) occurs in a high frequency band, and the sound pressure is reduced, resulting in poor frequency characteristics.

In view of such problems, various vibration plates having improved rigidity have been provided.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 4999899

Patent document 2: united states patent 9277324

Patent document 3: WO2014/045008

Patent document 4: japanese laid-open patent publication No. 50-144426

Disclosure of Invention

Technical problem to be solved by the invention

The diaphragm of patent document 1 adopts a free edge structure in which a center cover portion and a cone portion are integrally formed.

However, the diaphragm having the center cover portion and the cone portion integrated as described above has the following problems: the sound pressure in the high frequency band is attenuated due to the split resonance (japanese: split resonance), and the resonance point is low, and reproduction may be problematic in a case where the frequency band intended to be reproduced is involved.

Therefore, a method of increasing the frequency of the divided resonance point is devised.

If the thickness of the vibrating plate is increased to increase the rigidity, the single component as in patent document 1 has the following problems: the sound pressure decreases when the entire thickness becomes thick and the mass increases more than necessary.

If the total height is increased, there is the following problem: the size becomes large, which affects the wearing feeling, and a desired design cannot be realized.

Patent document 2 discloses a configuration in which a ring member, which is another member, is provided on the outer periphery of a center cover portion. That is, the outer peripheral portion of the central cover portion is joined to the inner periphery of the annular member, and the edge portion is joined to the outer peripheral portion of the annular member. The vibration plate thus constructed has the following problems: alignment of the respective members is difficult, and the manufacturing process is complicated.

Patent document 3 also adopts a configuration in which an annular member is joined to the outer periphery of the center cover portion, but in this case, in order to ensure rigidity, the annular member is also formed in a dome shape, and the thickness of the annular member is twice or more the thickness of the center cover portion.

In patent document 3, since the annular member must be formed in a dome shape, the manufacturing is complicated, and when the thickness is increased, the mass is increased, which causes a problem of a decrease in sound pressure.

Patent document 4 discloses a structure in which a reinforcing ring portion is coupled to the inside of the outer peripheral portion of a center cover portion.

The vibrating plate has the following problems: the reinforcing ring portion needs to be manufactured and joined in a manner conforming to the shape of the inner side of the curved outer peripheral portion of the dome-shaped center cover portion, leading to a problem that the shape of the center cover portion is changed and the manufacturing is cumbersome.

The present invention has been made to solve the above problems, and an object of the present invention is to: provided is a diaphragm for a speaker, which can easily improve rigidity and frequency characteristics on a high-band side without changing the shape of a main body member of the diaphragm composed of a center cover part and a cone part on the outer peripheral part thereof.

Technical scheme for solving technical problem

A speaker diaphragm according to an embodiment of the present invention according to claim 1 is characterized in that: the main body member of the speaker diaphragm includes a center cover portion and a cone portion formed on an outer periphery thereof, a ring member is joined to the cone portion of the main body member, and an inner peripheral portion of a rim is joined to the ring member or an outer peripheral portion of the cone portion.

An embodiment of the present invention according to claim 2 is the speaker diaphragm according to claim 1, wherein: the central cover portion has a dome shape, and the ring member having the same shape as the tapered portion is joined to the front surface or the rear surface of the tapered portion.

An embodiment of the present invention according to claim 3 is the speaker diaphragm according to claim 1, wherein: a diaphragm fixing ring is joined to an outer peripheral portion of the edge.

An embodiment of the present invention according to claim 4 is the speaker diaphragm according to claim 1, wherein: the body member and the ring member are formed by adding a bio-cellulose and a carbon fiber to a slurry.

An embodiment of the present invention according to claim 5 is the speaker diaphragm according to claim 1, wherein: the tapered portion to which the ring member is joined has a shape rising toward the front.

An embodiment of the present invention according to claim 6 is the speaker diaphragm according to claim 1, wherein: the vibrating plate for the loudspeaker is used for earphones.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the embodiment of the present invention, the ring member is coupled to the tapered portion to increase the rigidity of the tapered portion without changing the shape of the main body member composed of the central cover portion and the tapered portion of the outer periphery thereof. Therefore, the thickness of the tapered portion of the main body member can be controlled to be uniform in the circumferential direction, the rigidity of the main body member can be improved even if the main body member is thin and lightweight, and the increase in the overall mass can be suppressed even if the ring member is joined to the tapered portion, so that the reduction in sound pressure and the attenuation of sound pressure in a high frequency band can be suppressed.

Since the rigidity of the tapered portion, which is the outer peripheral portion of the main body member, can be increased, the split resonance point can be displaced in a high frequency band, and a decrease in sound pressure in the high frequency band can be prevented, thereby improving the frequency characteristics.

Since the tapered portion has an upright shape inclined toward the front (front of the speaker), the following advantages are obtained: easy to position in the radial direction (center alignment), easy to manufacture, and improved in rigidity when in an upright shape.

Drawings

FIG. 1 is an exploded perspective view of one embodiment of the present invention;

FIG. 2 is an assembled perspective view of the upper view;

FIG. 3 is a top view of the upper diagram;

FIG. 4 is a half sectional view of the upper drawing;

FIG. 5 is an illustration of the frequency characteristics of one embodiment of the present invention;

fig. 6 is an explanatory diagram of a frequency characteristic in the related art.

Detailed Description

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

The speaker diaphragm according to the embodiment of the present invention is configured as follows: the main application of the earphone is to the earphone, and the material of the earphone is preferably paper material and is of a free edge type.

In fig. 1, reference numeral 1 denotes a body member of a diaphragm, and the body member 1 includes a dome-shaped central cover portion 1a and a flange-shaped tapered portion 1b formed to extend radially outward from an outer peripheral edge thereof. The ring member 2 has substantially the same shape as the tapered portion 1b, and is formed integrally by overlapping the tapered portion 1b with a urethane or rubber adhesive and joining the same by hot press bonding. The ring member 2 is formed into a flat plate shape separately from the main body member 1 by paper making, and has a simple shape that is easy to manufacture. In the present invention, the rigidity of the tapered portion 1b can be improved without changing the shape of the tapered portion by making the shape of the ring member 2 substantially the same as the tapered portion 1 b. Further, by using the annular member, the annular tapered portion 1b of the main body member 1 can be accurately bonded to the annular tapered portion, and a vibration plate that is uniform in the circumferential direction can be configured. In this way, the ring member 2 is attached around the entire circumference of the tapered portion 1b of the body member 1, whereby the body member 1 as a whole can be moved in phase. In fig. 1, the ring member 2 is attached to the front surface of the tapered portion 1b, but may be attached to the front surface or the back surface of the tapered portion 1 b.

The ring member 2 and the main body member 1 including the central cover portion 1a and the tapered portion 1b are preferably formed by adding a predetermined amount of biocellulose and carbon fiber as a reinforcing material to the same raw material, for example, pulp (cellulose) such as wood pulp or non-wood pulp, to improve the rigidity of the raw material. The reinforcing material is not limited to the microfibers and carbon fibers, and other reinforcing materials may be used.

The amount of the biocellulose or the reinforcing material, i.e., the carbon fiber or the like, added to the slurry is an optimum addition ratio selected as appropriate in accordance with the use of the speaker diaphragm.

In fig. 1, 3 denotes an annular and dome-shaped edge, and 4 denotes a metal diaphragm fixing ring.

The inner peripheral portion of the rim 3 is joined to the ring member 2 or the outer peripheral portion of the cone 1b by an adhesive, and the diaphragm fixing ring 4 is joined to the outer peripheral portion of the rim 3 on the back side in the illustrated state, but may be joined to the front side in some cases.

Fig. 2 is a perspective view of an assembled state, and fig. 3 is a plan view.

Fig. 4 is a half sectional view showing a state in which the diaphragm fixing ring 4 to which the above-described speaker diaphragm 10 is joined is provided on the frame 5 of the speaker and the voice coil bobbin 6 is joined to the back surface of the boundary portion between the central cover portion 1a and the cone portion 1b of the main body member 1.

The tapered portion 1b to which the ring member 2 is joined has an upright shape inclined toward the front of the speaker. Therefore, positioning (centering) is easy and manufacturing is easy. The tapered portion 1b has an upright shape that rises from the inner peripheral side to the outer peripheral side, and the rigidity is increased by the shape when the angle of the upright shape is increased.

In the standing shape, the apex of the center cover portion 1a is higher than the outer periphery of the tapered portion 1b, but in a case where the height is not limited, the outer periphery of the tapered portion 1b may be higher than the apex of the center cover portion 1 a.

As is well known, a voice coil is wound around the outer periphery of the voice coil bobbin 6, and the voice coil is disposed in a magnetic gap of a magnetic circuit or the like (none of them are shown), thereby constituting a speaker for an earphone. When a voice signal is input to the voice coil, the speaker diaphragm 10 having the above-described structure coupled to the voice coil bobbin vibrates to generate a sound.

The earphone is a speaker of a type to be worn on the head, and is not limited to an earphone that covers the ear such as a head mount type, and includes so-called earphones such as an ear canal type, an earplug type, and an ear hook type. The voice coil may be joined to the speaker diaphragm 10 directly, not via the voice coil bobbin 6, but via the voice coil bobbin 6 instead of the speaker diaphragm 10. By directly bonding the voice coil to the speaker diaphragm 10, the weight can be reduced.

Fig. 5 shows a comparison of the frequency characteristic of the speaker diaphragm of the present invention and the frequency characteristic of a speaker diaphragm made of a single paper material member in the related art, in which a solid line a shows an example of the present invention and a broken line B shows a conventional example. Note that the frequency characteristic of fig. 5 is measured in the anechoic chamber. The present invention example a and the conventional example B are speaker diaphragms manufactured using paper materials having the same addition ratio of slurry, carbon fiber, and bio-cellulose and having different basis weights (weights).

The vibration conditions of the speaker diaphragms of invention example a and conventional example B in 10kHz and 12kHz were observed. In both the diaphragms of invention example a and conventional example B, the center cover portion 1a and the cone portion 1B vibrate in phase at 10kHz, and both a and B similarly obtain high sound pressure characteristics as shown in fig. 5. At 12kHz, the center cover portion 1a and the cone portion 1B of the diaphragm of invention example a vibrate in phase, whereas the center cover portion 1a and the cone portion 1B of the diaphragm of conventional example B vibrate in opposite phases. As described above, the speaker diaphragm according to example a of the present invention can vibrate the center cover portion 1a and the cone portion 1b in phase even at 12kHz, and can reduce split resonance. Therefore, as shown in fig. 5, the present invention example a can obtain a good sound pressure characteristic even in the high frequency band 12kHz of 10kHz or more, as compared with the conventional example B.

As a result of various experiments conducted on the paper material of conventional example B, the grammage of a speaker having a diameter of 14mm (the outer diameter of the diaphragm fixing ring) was 50g/m²And the slurry is preferably added with carbon fiber and biological cellulose. However, even in this specification, in terms of frequency characteristics, the sound pressure is reduced in the high frequency band of 10kHz or more. The same material addition ratio and gram weight as in conventional example B were set to 75g/m²The manufactured diaphragm for a speaker, which is made of a single paper material, has increased mass and reduced sound pressure over the entire frequency band, and is not shown in the drawings.

On the other hand, the grammage is 40g/m²The tapered portion 1b of the body member 1 is bonded with a weight of 40g/m²The same diameter ring member 2 of the invention example a can suppress the increase in mass, ensure sound pressure to about 20kHz, and obtain good frequency characteristics.

In the above embodiment, as described above, the frequency characteristics can be finely adjusted by changing the addition ratio of the carbon fibers and the biological cellulose to the slurry.

In the illustrated example, one ring member 2 is bonded to the tapered portion 1b, but the rigidity can also be adjusted by bonding a plurality of ring members.

The body member 1 and the ring member 2 are not limited to the combination of the same material, and may be a combination of different materials such as resin and metal.

Description of the symbols

10 diaphragm for speaker

1 main body part

1a center cover part

1b taper part

2 Ring component

3 edge of

4 vibrating plate fixing ring

5 frame

6 Voice coil bobbin (Voice coil)

Examples of the invention

B conventional example