JPH077789A - Cone type speaker - Google Patents

Abstract

PURPOSE:To provide a cone type speaker of easily listenable sound quality by reducing the optical peak of sound pressure frequency characteristics and generating a dip in optional frequency. CONSTITUTION:A mechanical resonator 2 mounted near the joining part of a cone type diaphragm 1 with a voice coil bobbin 4 is provided with and the intrinsic resonance frequency of the mechanical resonator 2 is set near the optional peak frequency of the cone type diaphragm 1. By this constitution, the mechanical resonator 2 generates resonance near the peak frequency, the driving energy of a voice coil 3 is absorbed by the mechanical resonator 2, the amplitude of the cone type diaphragm 1 is decreased near the peak frequency and the peak is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cone type speaker that reproduces a sound quality that is easy to hear by reducing the peak of a cone type diaphragm or making a dip suitable for sound pressure frequency characteristics. .

[0002]

2. Description of the Related Art In recent years, in order to comfortably reproduce a high-quality digital music source, it has been desired to reduce the peak of the sound pressure frequency characteristics of a cone type speaker to eliminate annoying sound as much as possible. . It is also desired to control the sound pressure frequency characteristics of the cone type speaker so that the sound quality can be easily heard in addition to reducing the peak.

By the way, the sound pressure frequency characteristic peak of the cone type speaker is often generated by the high frequency resonance of the cone type diaphragm.

Therefore, the high frequency resonance will be described first. FIG. 10 shows a computer simulation model diagram of a conventional cone type speaker, which is in a non-deformed state in which no signal is input. FIG. 11 shows a computer simulation vibration mode when a signal of the first high-frequency resonance frequency is input, and it can be seen that the outermost circumference of the cone-type diaphragm is most resonated and deformed. That is, the antinode of resonance is the outermost periphery of the cone-type diaphragm.

FIG. 12 shows a computer simulation vibration mode when a signal of the second high-frequency resonance frequency is inputted. The antinode of resonance deformation increases to two, and the part of large resonance deformation is larger than the outermost circumference. It moves inward and is slightly closer to the outer circumference of the cone type diaphragm. Similarly, FIG. 13 shows a computer simulation vibration mode in the case of the third high-frequency resonance, but the number of antinodes of resonance deformation is three, and the large deformation portion is farther to the inner circumference side of the cone-type diaphragm. You can see that they are moving.

As described above, the high frequency resonance is resonance in which a standing wave is placed on the cone type diaphragm, and a peak appears in the sound pressure frequency characteristic. Further, the higher the high-frequency resonance is, the more the number of antinodes of the resonance deformation increases, and the portion having the large resonance deformation moves to the inner peripheral side of the cone-type diaphragm.

A conventional cone type speaker designed to reduce the high frequency resonance peak will be described below with reference to the drawings. Fig. 14 shows a caliber 18c designed to reduce the high-frequency resonance peak.
It is a sketch of the conventional cone type speaker of m.

The cone type diaphragm 51 is attached to a voice coil bobbin 54, and the outer periphery thereof is supported by an edge 56 attached to a frame 58. Further, a dust cap 55 is attached to the inner peripheral part thereof. The voice coil 53 is a damper 5 attached to the frame 58.
It is held in the magnetic gap of the field portion 59 by 7. For the edge 56, a material such as expanded butyl rubber or elastomer having a large internal loss, that is, a large viscosity is used in order to reduce the high-frequency resonance peak.

With this configuration, the outermost periphery of the cone-type diaphragm 51 moves most in the first high-frequency resonance as described above, so that a large internal loss of the edge 56, that is, a viscous force is received. That is, the first high-frequency resonance mode is damped, and the first high-frequency resonance peak is reduced.

[0010]

However, in the above-mentioned conventional configuration, it is difficult to dampen the modes higher than the secondary high-frequency resonance because there is no portion of large resonance deformation at the outermost periphery of the cone type diaphragm. Therefore, there is a problem that the high-frequency resonance peaks of the second order and above cannot be reduced.

It is known that sound quality can be easily heard by making an appropriate dip in the mid-high range of the sound pressure frequency characteristic to lower the level of the mid-high range to some extent. It was very difficult to control the frequency characteristics in that way, and an equalizer circuit using a coil and a capacitor had to be added.

FIG. 9 shows a computer simulation sound pressure frequency characteristic diagram (solid line) of a conventional cone type speaker. Although the peak of the first high frequency resonance is low near 1.6 kHz, it is the second peak near 3.2 kHz. It can be seen that the peak of the next high frequency resonance remains high.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a cone type speaker capable of reducing peaks and freely creating dips at arbitrary frequencies.

[0014]

In order to achieve this object, the cone type speaker of the present invention has a mechanical resonator attached near the joint between the cone type diaphragm and the voice coil bobbin.

[0015]

With this configuration, the mechanical resonator resonates in the vicinity of the natural resonance frequency of the mechanical resonator, and the drive energy of the voice coil is absorbed by the mechanical resonator. Therefore, the amplitude of the cone type diaphragm decreases near that frequency, and a dip can be made in the sound pressure frequency characteristic. The peak can be reduced by setting the natural resonance frequency of the mechanical resonator near the peak frequency.

[0016]

EXAMPLES Examples of the present invention will be described below. First, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sketch of one embodiment of the cone type speaker of the first invention of the present invention.

The cone type speaker has a diameter of 18 cm. 1 is a cone type diaphragm, the material is 0.4mm thick
Is a polypropylene sheet. Reference numeral 2 is a mechanical resonator, 3 is a voice coil and has a diameter of 32 mm, 4 is a voice coil bobbin, a material is a polyamide resin having a thickness of 0.075 mm, 5 is a dust cap, a diameter is 57 mm, and a material is a cloth having a thickness of 0.4 mm. 6 is an edge, the material is an elastomer resin having a thickness of 0.2 mm, 7 is a damper, 8 is a frame, 9 is a field part, and all except the mechanical resonator 2 are shown in FIG. It is the same as the conventional one shown.

The mechanical resonator 2 is composed of a mass (mass) portion 2a and a suspension portion 2b, and is attached to the top of the voice coil bobbin 4. The material of the mechanical resonator 2 is polypropylene resin for injection.

The mass portion 2a has a conical shape and has a hole having a diameter of 10 mm for air circulation in the center thereof and a thickness of 1.5 mm. The mass portion 2a has a conical shape so that the mass portion 2a can move integrally without being deformed at a high frequency.
The suspension part 2b has a radius of curvature of 2.8 mm and a width of 4 m.
The m-shaped roll has a thickness of 0.27 mm. In this way, the natural resonance frequency of the mechanical resonator 2 is set to be in the vicinity of 3.2 kHz which is the second-order high frequency resonance frequency.

A dust cap 5 is attached to the inner peripheral portion of the cone type diaphragm 1 so as to cover the mechanical resonator 2.

The operation of the cone type loudspeaker of this embodiment constructed as described above will be described below.

When a signal in the vicinity of 3.2 kHz of the second high frequency resonance frequency is applied, the mechanical resonator 2 has its natural resonance frequency set in the vicinity of 3.2 kHz, so that the mass portion 2a vibrates violently and resonates. Cause Then, since the driving energy transmitted from the voice coil bobbin 4 is absorbed by the mechanical resonator 2, the amplitude of the cone-type diaphragm 1 decreases near 3.2 kHz which is the second high frequency resonance frequency, and 3.2 kHz. Near peaks are reduced.

Since the mechanical resonator 2 is covered with the dust cap 5, its natural resonance sound is not emitted and a very high quality reproduced sound can be obtained.

Now, the operation of the cone type speaker of the present embodiment constructed as above, which is verified by computer simulation, will be described below.

FIG. 7 is a computer simulation model diagram of the cone type speaker of this embodiment. FIG. 8 is a computer simulation vibration mode diagram in the case where a signal of 3.2 kHz which is the second-order high-range resonance frequency is added to this simulation model as in the case of the conventional FIG. From this, it is obvious that the mechanical resonator vibrates violently, and the amplitude of the cone-type diaphragm is so small that the resonance mode shown in FIG. 12 is almost invisible.

FIG. 6 is a computer simulation sound pressure frequency characteristic diagram of the cone type loudspeaker of the above embodiment (solid line).
Indicates. It can be seen that the secondary high-range resonance peak near 3.2 kHz, which has the highest level in FIG. 9, is collapsed and greatly reduced in FIG.

As described above, according to this embodiment, the mechanical resonator 2 is provided at the top of the voice coil bobbin 4 (that is, near the joint between the cone type diaphragm 1 and the voice coil bobbin 4).
Is attached to the mechanical resonator 2 and the natural resonance frequency of the mechanical resonator 2 is set near an arbitrary high resonance frequency of the cone type diaphragm 1, so that the mechanical resonator 2 resonates near the high resonance frequency. The drive energy of the coil 3 is absorbed there, and the amplitude of the cone type diaphragm 1 is reduced, so that the peak of the high frequency resonance frequency can be reduced.

Although the mechanical resonator 2 is made of polypropylene in this embodiment, it goes without saying that it may be made of paper, metal or other material. Further, although the mechanical resonator 2 is composed of the mass portion 2a and the suspension portion 2b, it does not have to be divided into the two portions as described above, but may be, for example, an integral flat plate-like one or another shape. .

Further, in the present embodiment, the natural resonance frequency of the mechanical resonator 2 is set near the second high frequency resonance frequency, but if another peak is desired to be reduced, it may be set near the peak frequency. . Further, in order to obtain a sound quality that is easy to listen to, it is possible to set a natural resonance frequency aiming at a frequency band that is offensive to the ears and make a dip in the sound pressure frequency characteristic.

Further, in this embodiment, the mechanical resonator 2 is attached to the top of the voice coil bobbin 4, but this is provided near the base of the cone type diaphragm 1 and the voice coil bobbin 4.
It may be attached to the lower side of the joint portion of the cone type diaphragm 1 (upper side of the damper 7) or the like. Further, in the present embodiment, the hole is provided in the central portion of the mechanical resonator 2, but it does not matter if the hole is not provided.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 2 is an enlarged schematic view of the central portion of the cone type speaker of the second embodiment of the present invention. The diameter of the speaker is also 18 cm. The difference from the first embodiment is only the mechanical resonator portion, and the other configurations are exactly the same, so description thereof will be omitted.

The first mechanical resonator 12 is composed of a mass portion 12a and a suspension portion 12b, and is provided on the inner peripheral side of the mounting position. The second mechanical resonator 20 is composed of a mass portion 20a and a suspension portion 20b, and is provided on the outer peripheral side of the mounting position. These materials are polypropylene resins for injection.

The first mechanical resonator has the same shape and size as those of the first embodiment. The second mass portion 20a has a cone shape with a diameter of 50 mm and a thickness of 0.9 mm, and the second suspension portion 20b has a roll shape with a radius of curvature of 1.7 mm and a width of 3 mm and a thickness of 0.4 mm.

In this way, the natural resonance frequency of the first mechanical resonator 12 is in the vicinity of 3.2 kHz which is the second high frequency resonance frequency, and the second mechanical resonator 2
3. The natural resonance frequency of 0 is the third high frequency resonance frequency.
It is set to be around 4 kHz.

A dust cap 15 is attached to the inner peripheral portion of the cone type diaphragm 11 so as to cover the first mechanical resonator 12 and the second mechanical resonator 20.

The operation of the cone type loudspeaker of the present embodiment having the above-mentioned structure will be described below.

3.2 kHz which is the second high frequency resonance frequency
The operation when a nearby signal is applied is as already described in the first embodiment. Similarly, the operation of the second mechanical resonator 20 when a signal near the third high-frequency resonance frequency of 4.4 kHz is applied, the natural resonance frequency of the second mechanical resonator 20 is set to around 4.4 kHz. The second mass portion 20a vibrates violently and causes resonance. Then, the driving energy of the voice coil 13 is absorbed by the second mechanical resonator 20, so that the amplitude of the cone type diaphragm 11 decreases near 4.4 kHz, which is the third high-frequency resonance frequency, and 4.4 kHz. Near peaks are reduced. That is, the peaks of both the second and third high frequency resonances are reduced.

As described above, according to the present embodiment, the first mechanical resonator 1 in which the respective natural resonance frequencies are set near the arbitrary two peak frequencies of the cone type diaphragm 11 is obtained.
By disposing the second mechanical resonator 20 and the second mechanical resonator 20 on the inner peripheral side and the outer peripheral side of the mounting position, respectively, the first mechanical resonator 12 and the second mechanical resonator 20 resonate near each peak frequency. Since it occurs, the driving energy of the voice coil 13 is absorbed there, and the amplitude of the cone type diaphragm 11 is reduced, and two arbitrary peaks can be reduced.

In this embodiment, the natural resonance frequencies of the first and second mechanical resonators 12 and 20 are near the secondary and tertiary high frequency resonance frequencies, but near the arbitrary frequencies according to the purpose. Needless to say, it may be set to.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 3 is an enlarged schematic view of a central portion of a cone type loudspeaker according to a third embodiment of the present invention.
The loudspeaker of this embodiment also has a diameter of 18 cm, and the mechanical resonator 22 is made of the same material and has the same dimensions as those of the first embodiment. The natural resonance frequency is also set near 3.2 kHz.

The difference is that the cone type diaphragm 21 and the mechanical resonator 22 are integrally formed,
The other structure is exactly the same as that of the first embodiment. The cone type diaphragm 21 is made of polypropylene for injection and has a thickness of 0.4 mm, and has a second shape near 3.2 kHz.
There is a peak of the next high frequency resonance.

The operation and effect of the cone type loudspeaker of this embodiment constructed as described above are exactly the same as those of the first embodiment. However, in this embodiment, the cone type diaphragm 21 and the mechanical resonator 22 are Since it is integrally molded, it also has an effect that the cone type speaker can be easily manufactured.

Next, a fourth embodiment of the present invention will be described with reference to FIG.
Will be described with reference to. FIG. 4 is an enlarged schematic view of a central portion of a cone type loudspeaker according to a fourth embodiment of the present invention, except that a viscoelastic material 40 is newly attached to the mechanical resonator 32. The configuration is the same as that in the first embodiment.

The viscoelastic material 40 is butyl rubber having a thickness of 1 mm and is divided and attached to the suspension portion 32b.

The operation and effect of the cone type loudspeaker of this embodiment constructed as described above are basically the same as those of the first embodiment, but in this embodiment the viscoelastic material 40 is the mechanical resonator 32. Attached to the mechanical resonator 3
The Q of the natural resonance of 2 decreases, and the width of the frequency for absorbing the driving energy of the voice coil 33 becomes wider.

That is, even if the natural resonance frequency of the mechanical resonator 32 deviates from the peak frequency of the cone type diaphragm 31 to some extent, the peak can be reduced, so that the mass-production variation of the characteristics of the cone type speaker can be reduced. Also has.

Further, since a broad dip can be formed on the sound pressure frequency characteristic over a wide band, control of sound quality becomes easier.

Finally, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 5 is a schematic view of a cone type loudspeaker according to a fifth embodiment of the present invention. It has no dust cap, the mechanical resonator 42 and the mechanical resonator 42 are at the base of the cone type diaphragm 41. It has the same configuration as in the first embodiment except that it is attached.

In this embodiment, the mass portion 42a of the mechanical resonator 42 has a dome shape and has no hole at the center. The mechanical resonator 42 also serves as a dust cap. The material is inexpensive styrene resin.

The operation and effect of the cone type speaker of the present embodiment configured as described above are the same as those of the first embodiment, but since a dust cap is not required separately in this embodiment, the cone type speaker It also has the effect of facilitating manufacturing.

In this embodiment, the mechanical resonator 42
Is attached to the base of the cone type diaphragm 41, but may be attached to the top of the voice coil bobbin 44 or the like.

[0052]

As described above, in the cone type speaker of the present invention, by mounting the mechanical resonator in the vicinity of the joint between the cone type diaphragm and the voice coil bobbin, in the vicinity of the natural resonance frequency of the mechanical resonator, The mechanical resonator resonates. Therefore, the driving energy of the voice coil is absorbed there and the amplitude of the cone type diaphragm is reduced, so that the peak can be reduced and the sound pressure frequency characteristic can be freely made a dip.

Further, by providing two mechanical resonators having different natural resonance frequencies on the inner peripheral side and the outer peripheral side of the mounting position respectively, the peaks of any two frequencies of the cone type diaphragm are reduced. You can

Further, by integrally molding the cone type diaphragm and the mechanical resonator, the cone type speaker can be easily manufactured.

Further, by attaching a viscoelastic material to the mechanical resonator, the Q of the natural resonance of the mechanical resonator can be obtained.
Therefore, even if the natural resonance frequency of the mechanical resonator deviates from the peak frequency of the cone-type diaphragm to some extent, the peak can be reduced, and variations in the characteristics of the cone-type speaker in mass production can be reduced. Furthermore, it becomes easy to control the sound pressure frequency characteristics.

Further, since the mechanical resonator also serves as the dust cap, the cone type speaker can be easily manufactured.

As described above, the present invention can provide a cone type speaker having a sound quality that is easy to hear, and has great practical value.

[Brief description of drawings]

FIG. 1 is a schematic view of a cone type speaker according to a first embodiment of the present invention.

FIG. 2 is an enlarged schematic view of a central portion of a cone type speaker according to a second embodiment of the present invention.

FIG. 3 is an enlarged schematic view of a central portion of a cone type speaker according to a third embodiment of the present invention.

FIG. 4 is an enlarged schematic view of a central portion of a cone type speaker according to a fourth embodiment of the present invention.

FIG. 5 is a cone type spin according to a fifth embodiment of the present invention.
Mosquito sketch

FIG. 6 is a cone type spin according to the first embodiment of the present invention.
Computer simulation of sound pressure frequency characteristics

FIG. 7 is a computer simulation model diagram of the cone type speaker according to the first embodiment of the present invention.

FIG. 8 is a computer simulation 3.2 kHz vibration mode diagram showing the operation of the present invention.

FIG. 9 is a computer simulation sound pressure frequency characteristic diagram of a conventional cone type speaker.

FIG. 10 is a computer simulation model diagram of a conventional cone type speaker.

FIG. 11 is a computer simulation of a conventional cone-type speaker. First-order high-frequency resonance vibration mode diagram.

FIG. 12: Computer simulation of a conventional cone-type speaker Second-order high-frequency resonance vibration mode diagram

FIG. 13: Computer simulation of a conventional cone-type speaker Third-order high-frequency resonance vibration mode diagram

FIG. 14 is a sketch of a conventional cone-type speaker designed to reduce the high-frequency resonance peak.

[Explanation of symbols]

 1 cone type diaphragm 2 mechanical resonator 2a mass part 2b suspension part 3 voice coil 4 voice coil bobbin 5 dust cap 6 edge 7 damper 8 frame 9 field part

Claims (6)

[Claims] 1. A cone-type speaker comprising a mechanical resonator attached near a joint between a cone-type diaphragm and a voice coil bobbin. 2. The natural resonance frequency of the mechanical resonator is
2. The cone type speaker according to claim 1, wherein the cone type diaphragm is set near an arbitrary peak frequency. 3. The cone type speaker according to claim 1, wherein two mechanical resonators having different natural resonance frequencies are provided on the inner peripheral side and the outer peripheral side of the mounting position, respectively. 4. The cone type speaker according to claim 1, wherein the mechanical resonator and the cone type diaphragm are integrally molded. 5. The cone type speaker according to claim 1, wherein a viscoelastic material is attached to the mechanical resonator. 6. The cone type speaker according to claim 1, wherein the mechanical resonator also serves as a dust cap.