close

Вход

Забыли?

вход по аккаунту

?

JPH04223697

код для вставкиСкачать
Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JPH04223697
[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an
on-vehicle speaker device.
[0002]
2. Description of the Related Art As a conventional on-vehicle speaker device, for example, one
configured as shown in FIG. 6 is known, and in the following, with reference to the drawings, 1 is
a passenger compartment and 2 is a trunk room. The trunk room 2 is provided with a large
capacity speaker cabinet 5 which accommodates a bass speaker 3 having a large-area diaphragm
and is provided with a bass reflex port 4 for deep bass reproduction. Further, in the dashboard 6,
a speaker 7 for middle and high sound is installed.
[0003]
Generally, for deep bass reproduction, a large volume is required for the speaker device.
However, the space which can secure a large volume in the vehicle compartment is limited to the
trunk room, the door bag of the door, and the like. In the conventional configuration shown in
FIG. 6, since the speaker cabinet 5 is installed in the trunk room 2, the storage space for luggage
and the like in the trunk room 2 is reduced accordingly. In addition, even when the speaker
device is installed in the door pocket of the door, the amenity of the vehicle interior must be
03-05-2019
1
sacrificed.
[0004]
Further, when the low-pitched sound is reproduced in the vehicle compartment, the speaker
apparatus attached to the trunk room, the door pocket of the door, etc. is insufficient in strength.
Therefore, the energy loss due to the unnecessary vibration of the mounting portion is also large,
causing the generation of chattering noise and booming noise.
[0005]
Further, the sound field in the vehicle compartment created by the conventional configuration
shown in FIG. 6 is such that the bass range is for bass even if the mid-high range such as vocals
is localized to the front of the listener by the mid-high range speaker 7 Since the speaker 3 is
installed in the trunk room 2, the speaker 3 is localized behind the listener and lacks a sense of
unity of the sound field between the low range and the middle and high range.
[0006]
Further, the acoustic power radiated from the speaker device to the sound field space is
determined by the radiation impedance on the drive surface of the sound field space.
However, in the speaker device in the conventional example shown in FIG. 6, since the matching
of the acoustic impedance between the speaker device and the interior space of the vehicle is not
considered at all, the radiation efficiency and frequency characteristics of the acoustic power in
the interior space are optimized. I can not do it.
[0007]
SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems,
and a speaker apparatus is installed without using a space in a vehicle compartment or a trunk
room for the speaker apparatus, and a low frequency band integrated with middle and high
frequency bands is provided. The object is to realize a sound field in a vehicle compartment and
to improve matching of acoustic impedance between a speaker device and a vehicle interior
space so that highly efficient and flat frequency characteristics can be obtained over a wide
frequency band. It is.
03-05-2019
2
[0008]
SUMMARY OF THE INVENTION In order to solve the problem, the present invention is an onvehicle speaker device provided with an acoustic tube and a driver, and a car viewed from the
sound emission surface of the speaker device. If the lowest frequency among the frequencies at
which the imaginary part of the acoustic impedance to the indoor space is zero is FS, and if the
low frequency reproduction limit frequency in the free space of the speaker device is FO, then FO
and FS are The shape of the acoustic tube and the constant of the driver are set to be
substantially equal, and the opening of the acoustic tube is provided at a position where the
matching of the acoustic impedance between the acoustic tube of the speaker device and the
space inside the vehicle is the highest. It is.
[0009]
According to the present invention, according to the above-described configuration, the speaker
apparatus is installed without using the space in the vehicle compartment or the trunk room for
the speaker apparatus, and the sound field of the low frequency band integrated with the middle
and high frequency band is obtained. It can be realized in the passenger compartment.
Further, since the matching of the acoustic impedance between the speaker device and the
vehicle interior space is improved, highly efficient and flat frequency characteristics can be
obtained over a wide frequency band.
[0010]
DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will
be described below with reference to FIGS.
Generally, the value of FS (the lowest frequency among frequencies at which the imaginary part
of the acoustic impedance to the vehicle interior space viewed from the acoustic emission surface
of the speaker device becomes zero) is the volume, shape, etc. of the vehicle interior space, or It
is determined by the size of the acoustic radiation surface and the like. However, since the value
of FS in the actual vehicle interior space is about 10 Hz to 40 Hz, the reproduction of the
frequency band below that is with the FO of the speaker device (low frequency reproduction limit
03-05-2019
3
frequency in free space of the speaker device alone) Although the flat frequency characteristics
can be obtained by equalizing FS, the design of the reproduction sound field of the frequency
band beyond that needs to be controlled by another method.
[0011]
The acoustic power radiated from the acoustic tube of the speaker device to the acoustic field
space is determined by the radiation impedance at the opening of the acoustic tube, which is a
connection point between the acoustic tube and the acoustic field space. Therefore, the opening
of the acoustic tube is provided at a position where the acoustic impedance of the opening of the
acoustic tube and the acoustic impedance of the vehicle interior space are most matched. That is,
the opening portion of the acoustic pipe is provided in a place having a horn shape such that the
space shape maintains a certain degree of continuity with the shape of the acoustic pipe in the
vehicle interior space.
[0012]
FIGS. 3 and 4 show the relationship between two different types of spaces having different
volumes corresponding to the interior space of the vehicle and the speaker device, in which 11 is
a driver for the bass which is a driver, 12 is an acoustic tube, A space 13 in the vicinity of the
opening 14 of the sound tube 12 has a horn shape so as to maintain continuity with the shape of
the sound tube 12 to some extent, and a space 15 is a mere cubic space. FIG. 5 shows the results
of calculation of the frequency characteristics of the reproduced sound field in these two types of
spaces 13 and 15 using the finite element method.
[0013]
In the reproduction sound field in the space 13, the matching of the acoustic impedance at the
opening 14 of the sound 12 which is a connection point between the sound tube 12 and the
sound field space is better than that in the space 15, as shown in FIG. The radiation efficiency of
the acoustic power from the acoustic tube 12 to the reproduction space is also high. In addition,
since the energy reflected to the sound tube 12 at the opening 14 of the sound tube 12 is small,
intense resonance in the sound tube that greatly impairs the flatness of the frequency
characteristic in the reproduction sound field is suppressed, and in the reproduction sound field
High efficiency and flat frequency characteristics can be realized.
03-05-2019
4
[0014]
FIGS. 1 and 2 show an in-vehicle speaker apparatus according to an embodiment of the present
invention, wherein 21 is a car compartment, 22 is a trunk room, and a bottom part of a vehicle
body is below a rear seat of the car compartment 21. Since it has a concave shape, a low sound
speaker 23 which is a driver is provided here. Reference numeral 24 denotes an acoustic pipe
provided with partitions 26 at two places in the front and back in the internal cavity of a
columnar body frame 25 at the bottom of the vehicle body, and formed between the front and
rear partitions 26. A throat portion 27 connected to the bass speaker 23 is provided at one end
of the acoustic pipe 24 so as to guide the acoustic output of the bass speaker 23 to the acoustic
pipe 24. An opening 28 is provided at the other end of the acoustic tube 24 so as to open below
the dashboard 29. The reference numeral 30 denotes a speaker for middle to high-pitched sound
provided in the dashboard 29.
[0015]
As described above, if the opening 28 of the acoustic tube 24 is provided in the space below the
dashboard 29, this space is acoustically viewed, the upper and lower sides being the dashboard
and the floor, and the left and right sides being the side walls. Since the space is in the shape of
an enclosed horn, the acoustic impedance can be matched with the space in the compartment 21
at the opening 28 of the acoustic pipe 24. Therefore, the space in the compartment 21 can be
efficiently and flatly with frequency characteristics. It can emit acoustic power.
[0016]
Furthermore, in the loudspeaker system, it is necessary to set the shape of the acoustic tube 24
and the constant of the driver so that the low-frequency reproduction limit frequencies FO and FS
in the free space of the loudspeaker system are substantially equal.
For that purpose, the position of the partition 26 inside the body frame 25 may be adjusted. For
example, in the present embodiment, if the value of Fs determined by the volume, shape, etc. of
the space in the casing 21 is 38 Hz, the total length of the acoustic tube 24 at the one end 28 to
the other end 28 is FS The position of the partition 26 may be adjusted so as to be 2.26 m
corresponding to 1⁄4 wavelength of.
03-05-2019
5
[0017]
Further, by providing the bass speaker 23 outside the compartment 21, a large volume for bass
reproduction can be secured without using the space in the compartment 21 and the trunk room
22. Furthermore, in order to incorporate the speaker device into the vehicle body, there is no
unnecessary vibration of the attachment portion, and it is possible to reproduce low-pitched
sound with a sound quality.
[0018]
Also, since the opening 28 of the sound tube 24 is in front of the listener, it is integrated with the
middle to high range such as vocals localized forward by the middle to high tone speaker 30
installed inside the dashboard 29. A sound field in the low range can be realized.
[0019]
In this embodiment, as shown in FIG. 2, the same speaker apparatus for stereo reproduction is
configured by a total of two for L channel and one for R channel.
[0020]
Further, as a modification of the present embodiment, the position where the opening 28 of the
acoustic tube 24 is to be provided is a space enclosed above the dashboard 29 and under the
windshield in the passenger compartment 21, or above the rear parcel. Even as the tip of the
space enclosed under the rear window, it is a space having a horn shape respectively, so that the
matching of the acoustic impedance between the acoustic tube 24 and the space inside the
vehicle compartment 21 is good, and the same effect as the above embodiment Is obtained.
[0021]
As described above, according to the present invention, a low frequency band in which the
speaker device is installed without using the space in the vehicle compartment or the trunk room
for the speaker device, and which is integrated with the middle and high range Can be realized in
the passenger compartment.
Further, since the matching of the acoustic impedance between the speaker device and the
03-05-2019
6
vehicle interior space is improved, highly efficient and flat frequency characteristics can be
obtained over a wide frequency band.
[0022]
Brief description of the drawings
[0023]
1 is a side sectional view of an on-vehicle speaker device according to an embodiment of the
present invention.
[0024]
2 is a bottom view of the in-vehicle speaker device according to an embodiment of the present
invention.
[0025]
3 is a schematic side view showing a state in which the speaker device according to an
embodiment of the present invention is connected to a horn-shaped space.
[0026]
4 is a schematic side view showing a state in which the speaker device according to an
embodiment of the present invention is connected to a cubic space.
[0027]
FIG. 5 is a graph showing calculation results of frequency characteristics of sound pressure in
two types of reproduction spaces shown in FIG. 3 and FIG. 4.
[0028]
6 is a side sectional view of the in-vehicle speaker device in the conventional example.
[0029]
Explanation of sign
03-05-2019
7
[0030]
DESCRIPTION OF SYMBOLS 11 Loudspeaker 12 Acoustic tube 13 Space 14 Opening 15 Space
21 Cabin 22 Trunk room 23 Loudspeaker 24 Acoustic tube 25 Body frame 26 Partition 27
Throat 28 Opening 29 Dashboard
03-05-2019
8
Документ
Категория
Без категории
Просмотров
0
Размер файла
16 Кб
Теги
jph04223697
1/--страниц
Пожаловаться на содержимое документа