JP3240455B2 - Sound reproduction device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound reproducing apparatus, and more particularly to a sound reproducing apparatus for reproducing low sound in a vehicle cabin.

[0002]

2. Description of the Related Art In recent years, in the field of car audio, there has been a remarkable trend toward higher sound quality and higher power, and powerful reproduction has been made using a speaker having a large diameter even in a low sound range. In the case of car audio, the installation place of the speaker is limited, and a speaker with a large diameter requires a certain volume. Therefore, a speaker unit is installed on the rear panel in the trunk room and the rear panel is used as a baffle plate. The speaker cabinet is omitted, or a large-sized cabinet provided with a speaker unit is installed in a trunk room.

[0003]

However, as the diameter of the speaker unit becomes larger, the frame becomes larger and the weight becomes very heavy, and there is a certain limit to suspending the speaker unit from the rear panel. In addition, the speaker unit itself requires a certain amount of installation space, and the inside of the trunk room becomes very narrow, so that the loadable amount of luggage decreases. With a speaker cabinet, the inside of the trunk room becomes even smaller. The present invention has been made in view of the above-described problems of the related art, and has as its object to provide a sound reproducing device that is light in weight and can reproduce low-pitched sound in a vehicle cabin with a small installation space.

[0004]

According to the sound reproducing apparatus of the present invention, a vibrator driven by a sound signal is installed on a ceiling or a floor of a vehicle, and the vibrator includes two magnets magnetized in an axial direction. A repulsive magnetic circuit in which the same poles face each other, a voice coil which is disposed so as to interlink with a magnetic flux diverging to an external space from between two magnets of the repulsive magnetic circuit, and to which an acoustic signal is applied; It has a heavy magnetic body fixed integrally to the coil, two magnets are fixed in the case of the vibrator, and the voice coil with the heavy body is supported by the suspension so that it can vibrate freely. I have.

[0005]

Further, the vibrator has a repulsive magnetic circuit in which two magnets magnetized in the axial direction are arranged so that the same poles face each other, and a magnetic flux diverging to the external space from between the two magnets of the repulsive magnetic circuit. And a voice coil to which an acoustic signal is applied. The voice coil is fixed in a case of the vibrator, and the two magnets are supported by a suspension so as to be freely vibrated. I have.

[0007] Further, the present invention is characterized in that a magnetic material is integrally fixed to the voice coil, or a weight body integrally fixed to the voice coil is a magnetic material.

[0008]

[0009]

[0010]

According to the sound reproducing apparatus of the present invention, the vibrator is installed on the ceiling or floor of the vehicle, and the vibrator is driven based on the acoustic signal. Since the ceiling or floor of the vehicle has a resonance frequency inherent in the low range of about 50 Hz due to its structure, a large low-frequency sound can be generated only by exciting the ceiling or floor with a small shaker. In order to obtain the same volume, the vibrator is lighter than the bass speaker, the load on the vehicle is small, and the size is small, so there is no need for a large installation space. The space will not be forcibly reduced. In addition, the vibrator uses a repulsive magnetic circuit in which two magnets magnetized in the axial direction are arranged so that the same poles face each other, and emits a high-density magnetic flux from the two magnets to the external space. A large framing force is generated between the magnet and the voice coil by applying an acoustic signal to the voice coil arranged to link the magnetic flux. The weight body is fixed integrally to the voice coil of the shaker,
In the case of the vibrator, the two magnets of the repulsion magnetic circuit are fixed, and the voice coil with the heavy body is made to vibrate freely by the suspension. When the voice coil is driven, the voice coil vibrates relative to the case. Due to the recoil, the case of the vibrator applies vibration based on the acoustic signal to the ceiling or floor of the vehicle. The use of a repulsion magnetic circuit eliminates the need for a magnetic path member such as a yoke, so that the vibrator can be made thinner and lighter than using a general magnetic circuit to obtain the same volume, saving installation space and reducing running load. Can be smaller. In addition, it is not necessary to secure a large space for the two magnets to vibrate in the case of the vibrator, and the vibrator can be made much thinner than the type in which the two magnets vibrate. When the shaker is thinned, it can be installed under a seat such as a front seat when installed on the floor, and there is less protrusion when installed on the ceiling,
Does not disturb the crew. In addition, the mountability in the case where the vibrator is installed on the ceiling is improved by making the vibrator thinner and lighter.

[0011]

Further, the voice coil of the vibrator is fixed in the case of the vibrator, and the two magnets are freely vibrated by the suspension. Therefore, when the voice coil is driven, the two magnets vibrate relative to the case. Then, due to the reaction, the case of the vibrator applies vibration based on acoustic vibration to the ceiling or floor of the vehicle. Thus, since the voice coil is fixed to the case, wiring to the voice coil can be easily performed.

Further, the magnetic material is fixed to the voice coil, or the magnetic flux is concentrated on the voice coil by using a weight body integrally fixed to the voice coil as a magnetic material. This makes it possible to efficiently vibrate the ceiling or floor with the vibrator.

[0014]

[0015]

[0016]

FIG. 1 is a block diagram of a sound reproducing apparatus according to one embodiment of the present invention. Reference numeral 1 denotes a vibrator, which is fixed to a rib-like portion 3 of a floor 2 of a vehicle. In the vibrator 1, 4 is a box-shaped case, and 5 and 6 are axial directions (vertical direction in FIG. 1).
, And are arranged in the center of the case 4 so that the same poles (N poles in FIG. 1) face each other with the center plate 7 having a predetermined thickness interposed therebetween. The center plate 7 is made of a magnetic material, and forms a repulsion magnetic circuit 8 together with the magnets 5 and 6.
Holes 11 and 12 are formed in the center of the upper plate 9 and the bottom plate 10 of the case 4 so that the holes 11 and 12 of the upper plate 9, the center hole 13 of the repulsive magnetic circuit 8 and the hole 12 of the bottom plate 10 pass through. The case 4 is driven by tapping screws 14 driven from the outer surface of the case 4.
It is fixed to. The tip of the tapping screw 14 is screwed to the rib-shaped portion 3, whereby the vibrator 1 is fixed to the floor 2.

Outside the center plate 7 of the repulsion magnetic circuit 8, a cylindrical voice coil 15 is provided. The voice coil 15 is driven by an externally input acoustic signal. The repulsion magnetic circuit 8 diverges a high-density magnetic flux from between the two magnets 5 and 6 from the side surface of the center plate 7 to the horizontal external space in FIG. Accordingly, the magnetic flux can be concentrated at the position of the voice coil 15 without providing a magnetic path member such as a yoke, and the magnetic circuit can be made thinner and lighter.

A ring-shaped magnetic body 16 also serving as a heavy body is integrally mounted on the voice coil 15 so that the magnetic flux radiated from the repulsion magnetic circuit 8 is surely concentrated on the voice coil 15. . The voice coil 15 and the magnetic body 16 constitute a voice coil unit 17. The voice coil unit 17 is provided in the case 4 by two suspensions 18 and 19 provided between the upper end of the magnetic body 16 on the outer peripheral side and the case 4 and between the lower end of the outer peripheral side and the case 4. It is supported so that it can vibrate in the direction. To allow the case 4 to vibrate the rim-like portion 3 of the floor 2 by reaction when the voice coil portion 17 vibrates,
Is considerably heavy, but is firmly supported by the two suspensions 18 and 19 to prevent rolling.

The voice coil unit 17 can adjust the resonance frequency of the vibration by adjusting the weight of the magnetic body 16. In this embodiment, the floor 2 is vibrated by the vibrator 1. In order to generate a sound in a frequency range including a low frequency of about 50 Hz and a frequency higher than the low frequency, the weight of the magnetic body 16 is such that the resonance frequency of the vibration of the voice coil unit 17 is about 50 Hz with respect to the floor 2. It is adjusted so that a predetermined wide frequency range including a higher frequency range can be efficiently excited. In the present embodiment, as an example, the resonance frequency of the vibration of the voice coil unit 17 is set to about 20 Hz.

Next, the operation of the above embodiment will be described. Here, it is assumed that the vibrator 1 is fixed to the rib-like portion 3 of the floor 2 of the vehicle by the tapping screw 14 so as not to hinder the vibration of the vibrator 1. Repulsive magnetic circuit 8 of vibrator 1
As a result, a high-density magnetic flux diverging in the horizontal direction from the outer peripheral end face of the center plate 7 to the external space is generated. Since the magnetic flux is concentrated on the voice coil 15 by the magnetic material 16 of the voice coil unit 17, the magnetic flux linked to the voice coil 15 is very large. Here, when an acoustic signal containing a low frequency band of about 50 Hz and a frequency component higher than that is applied to the voice coil 15, the two magnets 5, 6
Then, a very large framing force is generated between the voice coils 15. The two magnets 5 and 6 are fixed in the case 4 of the vibrator 1, and the voice coil unit 1 with a magnetic material is provided.
Numeral 7 is vertically vibrated by two suspensions 18 and 19. By adjusting the weight of the magnetic body 16, the resonance frequency of the vibration of the voice coil unit 17 becomes
Since it is designed to efficiently excite a predetermined wide frequency range including a low range around 50 Hz and a higher range,
When the voice coil 15 is driven, the voice coil portion 17 vibrates very efficiently with respect to the case 4, and the reaction causes the case 4 to move the rib-like portion 3 of the floor 2 in a low frequency range based on an acoustic signal and a low frequency range. Vibrations in a predetermined wide frequency range including a higher frequency range are efficiently applied.

The floor 2 has a resonance frequency of about 50 Hz due to the structure of the vehicle body. Near the resonance frequency, a large sound is generated even if the vibration applied from the outside is small. For this reason, a sufficiently large bass sound can be reproduced even with a small vibrator 1. In particular, the rib-like portion 3 has higher strength than other flat portions, and the vibration of the vibrator 1 is transmitted to the rib-like portion 3 without being attenuated, so that the efficiency is good. Rib-shaped part 3 only by applying vibration of small amplitude
, A low-frequency, large-amplitude vibration can be generated in a flat portion that leads to. In addition, the rib-like portion 3 having strong strength is capable of not only vibration in a low frequency range but also in a higher frequency range. The flat portion connected to the rib portion 3 can reproduce sound in a wide frequency range from a low frequency to a high frequency.

According to this embodiment, the floor 2 is vibrated by using the vibrator 1 driven by an acoustic signal to reproduce sound.
As long as the resonance frequency of the floor 2 is near, a sufficiently large sound can be generated by the small vibrator 1. Therefore, compared to reproducing bass sound using a bass speaker,
It is possible to reduce the weight and size of the device, and when installing the device on the floor, the cabin space is not forcibly reduced and the load on traveling does not increase. Further, in the vibrator 1, since a high-density magnetic flux is generated by the repulsion magnetic circuit 8, a magnetic path member such as a yoke can be omitted as compared with using a normal magnetic circuit. The exciter 1 can be made thinner and lighter than using the magnetic circuit of (1). Therefore,
The installation space can be further saved and the running load can be further reduced. In addition, there is no need to secure a large space for the two magnets 5 and 6 to vibrate inside the case 4 of the vibrator 1, and the vibration is much greater than the type in which the two magnets 5 and 6 vibrate. The vessel 1 can be made thin. When the vibrator 1 is thinned, it can be installed under a seat such as a front seat when installed on the floor 2,
It does not get in the way of the crew. In addition, since the rib-like portion 3 of the floor 2 to be vibrated by the vibrator 1 is stronger than other flat portions, the vibration of the vibrator 1 is transmitted to the rib-like portion 3 without being attenuated. Vibration efficiency is good, and only a small amplitude vibration is applied to the rib-shaped portion 3 so that a flat portion connected to the rib-shaped portion 3 can generate low-frequency, very large-amplitude vibration. In addition, a rib-like portion 3 having strong strength
Can not only vibrate in the low frequency range but also in the higher frequency range. By applying not only the low frequency range but also the vibration in the higher frequency range, it is possible to reproduce sound in a wide frequency range. Further, since the vibration of the floor 2 excited by the exciter 1 is transmitted to the occupant's body via the seat, the bass sensation is hardly impaired even during traveling due to the body sonic effect, and the occupant can be relaxed.

In the above-described embodiment, the magnet is fixed in the case of the vibrator so that the voice coil portion can freely vibrate. On the contrary, as shown in FIG. 2, the voice coil portion is fixed and the magnet is fixed. May be freely oscillated. In FIG.
A through-hole 40 penetrating vertically through the centers of the magnets 5A and 6A of the repulsion magnetic circuit 8A and the center plate 7A is formed, and in the through-hole 40, the vibrator 1A is fitted with the rib-like portion 3 of the floor 2. A tapping screw 14 is loosely inserted to fix the screw. The repulsion magnetic circuit 8A includes two suspensions 4 provided between the outer peripheral upper end of the magnet 5A and the case 4 and between the outer peripheral lower end of the magnet 6A and the case 4.
The case 1 supports the case 4 so that it can vibrate up and down in FIG. On the other hand, the tubular voice coil 15
The voice coil unit 17A in which the ring-shaped magnetic body 16A is integrated with the voice coil unit 17A is directly fixed to the case 4. Since the repulsion magnetic circuit 8A has a considerable weight, the repulsion magnetic circuit 8A depends on the compliance of the suspensions 41 and 42.
The resonance frequency of the vibration is adjusted to a value that can efficiently excite a predetermined wide frequency range including a low range around 50 Hz and a high range above the floor 2 with respect to the floor 2. The other components are configured exactly the same as in FIG.

In the sound reproducing apparatus configured as shown in FIG. 2, when a sound signal including a low frequency band of about 50 Hz and a frequency component higher than that is applied to the voice coil 15, repulsive magnetism composed of the magnets 5A, 6A and the center plate 7A is obtained. An extremely large framing force is generated between the circuit 8A and the voice coil 15. The voice coil 15 is fixed in the case 4 of the vibrator 1A, and the repulsion magnetic circuit 8A is
Since the two suspensions 41 and 42 can freely vibrate in the vertical direction, when the voice coil 15 is driven, the repulsion magnetic circuit 8A vibrates very efficiently with respect to the case 4, and the reaction causes the case 4 to form a rib on the floor 2. For part 3,
Vibrations in a predetermined wide frequency range including a low frequency range and a higher frequency range based on the acoustic signal can be efficiently applied.

In the example of FIG. 1, the connection of the lead wire (not shown) to the voice coil 15 is troublesome because the voice coil portion 17 is made to freely vibrate in the case 4, but according to the example of FIG. Since the voice coil section 17A is fixed in the case 4, connection of the lead wires is simplified.

Further, in the above-described embodiments and modified examples, the vibrator is fixed to the rib-like portion of the floor, but may be fixed to the flat portion of the floor. Although a repulsion magnetic circuit is used for the vibrator, a normal magnetic circuit may be used, and a magnetic body integrally mounted on the voice coil may be omitted. Further, the case of the vibrator may be either a magnetic material or a non-magnetic material.

Since the ceiling of the vehicle, like the floor, has a resonance frequency of about 50 Hz due to the vehicle body structure, the vibrator is fixed to a rib-like or flat portion of the ceiling, and the ceiling is vibrated. By doing so, a low-frequency sound of about 50 Hz or a sound in a frequency range including a low-frequency sound of about 50 Hz and higher frequencies may be reproduced in the vehicle cabin. In particular, with a light and thin shaker using a repulsive magnetic circuit, there is little protrusion even when installed on the ceiling, it does not disturb the occupants,
The mountability when installing on a ceiling is improved by making the vibrator thinner and lighter. Further, the vibrator may be installed on only one of the floor and the ceiling, or may be installed on both the floor and the ceiling.

On the other hand, when the vibrator is installed on the floor, FIG.
In addition to fixing the vibrator directly to the floor with the tapping screw shown in FIG. 2 or the like, the vibrator may be simply fixed to a carpet laid on the floor so that the vibrator does not jump due to vibration.
For example, the exciter may be adhered to the carpet, or a hook may be hooked on the carpet, and the exciter may be fixed to the hook with rubber, a string, or the like. When the shaker is installed on the ceiling, the shaker may be fixed directly to the ceiling with a tapping screw or the like, or may be fixed to a ceiling sheet so that the shaker does not jump due to vibration. For example, the exciter may be bonded to the ceiling sheet, a hook may be hooked on the ceiling sheet, and the exciter may be fixed to the hook with rubber, a string, or the like.

Further, by incorporating a power amplifier for amplifying an acoustic signal in the vibrator, the power amplifier for the vibrator may be easily attached as a subwoofer without separately preparing a power amplifier.

[0030]

According to the sound reproducing apparatus of the present invention, the vibrator is installed on the ceiling or floor of the vehicle, and the vibrator is driven based on the acoustic signal. At this time, the ceiling and floor of the vehicle are structurally
Since it has a unique resonance frequency in a low frequency band of about 50 Hz, a large low frequency sound can be generated only by vibrating the ceiling or the floor with a small vibrator. In order to obtain the same volume, the vibrator is lighter than the bass speaker, the load on the vehicle is small, and the size is small, so there is no need for a large installation space. The space will not be forcibly reduced. In addition, the vibrator uses a repulsive magnetic circuit in which two magnets magnetized in the axial direction are arranged so that the same poles face each other, and emits a high-density magnetic flux from the two magnets to the external space. A large framing force is generated between the magnet and the voice coil by applying an acoustic signal to the voice coil arranged to link the magnetic flux. The weight body is fixed integrally to the voice coil of the shaker, and the repulsion magnetic circuit 2 in the shaker case.
The two magnets are fixed, and the voice coil with the heavy body is made to vibrate freely by the suspension, so when the voice coil is driven, the voice coil vibrates with respect to the case,
Due to the reaction, the case of the shaker applies vibration based on the acoustic signal to the ceiling or floor of the vehicle. The use of a repulsion magnetic circuit eliminates the need for a magnetic path member such as a yoke, so that the vibrator can be made thinner and lighter than using a general magnetic circuit to obtain the same volume, saving installation space and reducing running load. Can be smaller. In addition, it is not necessary to secure a large space for the two magnets to vibrate in the case of the vibrator, and the vibrator can be made much thinner than the type in which the two magnets vibrate. By making the vibrator thinner, it can be installed under a seat such as a front seat when it is installed on the floor, and when it is installed on the ceiling, there is less protrusion and it does not hinder the occupants. In addition, the mountability in the case where the vibrator is installed on the ceiling is improved by making the vibrator thinner and lighter.

[0031]

Also, the voice coil of the vibrator is fixed in the case of the vibrator, and the two magnets are freely vibrated by the suspension. Therefore, when the voice coil is driven, the two magnets vibrate relative to the case. Then, due to the reaction, the case of the vibrator applies vibration based on acoustic vibration to the ceiling or floor of the vehicle. Thus, since the voice coil is fixed to the case, wiring to the voice coil can be easily performed.

The magnetic material is fixed to the voice coil, or the magnetic flux is concentrated on the voice coil by using a weight body integrally fixed to the voice coil as a magnetic material. This makes it possible to efficiently vibrate the ceiling or floor with the vibrator.

[0034]

[0035]

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an audio reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a sound reproduction device according to a modification of the present invention.

[Explanation of symbols]

1, 1A Exciter 2 Floor 3 Rib-shaped part 4 Case 5, 6, 5A, 6A Magnet 8, 8A Repulsion magnetic circuit 14 Tapping screw 15 Voice coil 16, 16A Magnetic body 17, 17A Voice coil section 18, 19, 41 , 42 suspension

Claims (5)

(57) [Claims] 1. A sound reproducing apparatus in which a vibrator driven by a sound signal is installed on a ceiling or a floor of a vehicle, wherein the vibrator has two magnets magnetized in an axial direction arranged so that the same poles face each other. A repulsive magnetic circuit, a voice coil to which an acoustic signal is applied and linked to a magnetic flux diverging to the external space from between two magnets of the repulsive magnetic circuit, and a weight integrally fixed to the voice coil And a body, wherein two magnets are fixed in a case of the shaker, and a voice coil with a heavy body is supported by a suspension so as to be able to vibrate freely. 2. A sound reproducing apparatus in which a vibrator driven by a sound signal is installed on a ceiling or a floor of a vehicle, wherein the vibrator has two magnets magnetized in the axial direction arranged so that the same poles face each other. A repulsive magnetic circuit, and a voice coil to which an acoustic signal is applied so as to interlink with a magnetic flux diverging to an external space from between two magnets of the repulsive magnetic circuit, Wherein the voice coil is fixed and the two magnets are supported by a suspension so as to be able to vibrate freely. 3. The sound reproducing apparatus according to claim 1, wherein a magnetic body is integrally fixed to the voice coil. 4. The sound reproducing device according to claim 2, wherein a magnetic material is integrally fixed to the voice coil. 5. The sound reproducing apparatus according to claim 1, wherein the weight body is a magnetic body.