close

Вход

Забыли?

вход по аккаунту

JP2018074372

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 JP2018074372
Abstract: A speaker device is capable of suppressing a drop in sound pressure level in an inclined
direction. A speaker device extends between a diaphragm that outputs a sound wave by vibration
and an outer peripheral edge of the diaphragm and a central portion. And a covering portion
covering a partial region of the surface of the diaphragm. [Selected figure] Figure 6
Speaker apparatus, phase interference suppression method and speaker system
[0001]
The present invention relates to a speaker device, a phase interference suppression method, and
a speaker system.
[0002]
BACKGROUND Conventionally, a speaker device that can be mounted on a vehicle is known.
A speaker device that can be mounted on a vehicle, for example, constitutes a part of an onvehicle audio-visual navigation integrated device (hereinafter also referred to as an AVN device).
In a vehicle equipped with a speaker device, for example, navigation provided via an AVN device,
television (TV) broadcasting, AM / FM radio broadcasting, DVD (Digital Versatile Disk), BD (Bluray (registered trademark), etc. Sound waves of various contents such as a reproduced image
reproduced on a disc are output. A speaker device that can be mounted on a vehicle tends to be
provided, for example, on an instrument panel, a front seat side door, a rear seat door, etc. on
03-05-2019
1
which a speedometer, an operation switch, and the like are arranged.
[0003]
The following patent documents exist as prior art documents in which techniques related to the
techniques described in the present specification are described.
[0004]
JP, 2009-141884, A
[0005]
By the way, when outputting a sound wave using a speaker device, a part of the sound waves
output from different parts on the diaphragm reach the listening position because the distances
from the respective output parts to the listening position are different. Phase shifts occur and
interfere with each other.
When interference occurs, cancellation may occur between sound waves of bands in which the
respective sound waves output from different parts on the diaphragm are in antiphase (shifted by
half a wavelength) at the listening position.
When the sound waves in the opposite phase bands cancel each other out, the sound pressure
level decreases at the listening position. In such a phenomenon, the sound pressure level tends to
decrease in order from the sound wave of high frequency as the listening position is inclined
from the central axis passing through the center of the speaker device.
[0006]
Generally, in a speaker device that can be mounted on a vehicle, the mounting position on the
vehicle is restricted by the vehicle structure. Therefore, there is a case where a user who listens
to and listens to the sound wave output from the speaker device (hereinafter, also referred to as a
user) listens in a direction inclined from the central axis of the speaker device. When listening in
a direction inclined from the central axis of the speaker device, there is a possibility that the
sound quality may be degraded due to the high sound pressure level lowered by the cancellation
03-05-2019
2
of the sound waves of the bands in opposite phase at the listening position. is there. An object of
the present invention is to make it possible to suppress a drop in sound pressure level in an
inclined direction.
[0007]
One aspect of the disclosed technology is exemplified by a speaker device. That is, the speaker
device is provided with a diaphragm that outputs a sound wave by vibration, and a covering
portion that extends between the outer peripheral edge and the central portion of the diaphragm
and covers a partial region of the surface of the diaphragm. It features.
[0008]
According to the speaker device, it is possible to suppress the decrease in the sound pressure
level in the inclined direction.
[0009]
It is a figure explaining the speaker system in vehicles.
It is a figure explaining the attachment state of the speaker apparatus attached to the driver's
seat side in an instrument panel. It is a figure explaining the fall of the sound pressure level by
the inclination from a central axis. It is a figure explaining the fall of the sound pressure level of
the sound wave output from a speaker apparatus. It is a figure explaining the phase interference
of the sound wave output from the diaphragm of a speaker apparatus. It is a figure which shows
an example of a structure of the speaker apparatus which concerns on this embodiment. It is a
figure explaining suppression of the sound pressure level fall in the opposite side direction which
opposes on both sides of the field in which the phase interference control board was provided,
and a central axis. It is a figure which shows an example of the variation about the shape of a
phase interference suppression board. It is a figure which shows an example of the variation
about the shape of a phase interference suppression board. It is a figure explaining the distance
difference resulting from the opening diameter of a speaker apparatus. It is a figure explaining
the sound pressure level in, when a phase difference arises. FIG. 8 is a diagram showing an
example of the configuration of a speaker device according to Embodiment 2. FIG. 13 is a view
showing an example of a variation of the phase interference suppression plate of the second
embodiment. FIG. 13 is a view showing an example of a variation of the phase interference
03-05-2019
3
suppression plate of the second embodiment. FIG. 13 is a view showing an example of a variation
of the phase interference suppression plate of the second embodiment. FIG. 13 is a view showing
an example of a variation of the phase interference suppression plate of the second embodiment.
FIG. 13 is a view showing an example of a variation of the phase interference suppression plate
of the second embodiment. FIG. 13 is a view showing an example of a variation of the phase
interference suppression plate of the second embodiment. It is a figure explaining the rotational
movement along the outer periphery direction of the phase interference suppression board of
Embodiment 3. FIG. It is a figure which shows an example of the rotation mechanism which
rotationally moves the phase interference suppression board of Embodiment 3 along outer
peripheral direction. It is a figure explaining attachment fixation to the instrument panel of the
speaker apparatus of Embodiment 3. FIG. It is a figure explaining attachment fixation to the
instrument panel of the speaker apparatus of Embodiment 3. FIG. It is a graph which shows the
measurement result of the frequency characteristic of the speaker apparatus which concerns on
this embodiment. It is a graph which shows the measurement result of the frequency
characteristic of the speaker apparatus which concerns on this embodiment. It is a graph which
shows the measurement result of the frequency characteristic of the speaker apparatus which
concerns on this embodiment. It is a graph which shows the measurement result of the frequency
characteristic of the speaker apparatus which concerns on this embodiment. It is a graph which
shows the measurement result of the frequency characteristic of the speaker apparatus which
concerns on this embodiment. It is a graph which shows the measurement result of the frequency
characteristic of the speaker apparatus which concerns on this embodiment. It is a graph which
shows the measurement result of the frequency characteristic of the speaker apparatus which
concerns on this embodiment.
[0010]
Hereinafter, a speaker device according to an embodiment will be described with reference to the
drawings. The configurations of the following embodiments are examples, and the present
speaker device is not limited to the configurations of the embodiments.
[0011]
<1. System Configuration> FIG. 1 is an explanatory view of a speaker system in a vehicle. The
speaker system 1 in FIG. 1 is an example of a form having a plurality of speaker devices 10 that
can be mounted on the vehicle 2. In FIG. 1, the speaker system 1 configures, for example, a part
of an AVN device for vehicle use. The speaker system 1 includes in the vehicle 2 sound waves of
various contents such as a navigation function provided via an AVN device, television
03-05-2019
4
broadcasting, radio broadcasting, CD (Compact Disc), reproduced images reproduced by DVD, BD,
etc. Output.
[0012]
In the speaker system 1 illustrated in FIG. 1, the speaker device 10 mountable on the vehicle 2
includes, for example, an instrument panel 2a, a driver's seat side front door 2b, a passenger seat
side front door 2c, and a driver's seat side rear door 2d, provided on the passenger side rear door
2e. For example, in the speaker system 1 illustrated in FIG. 1, the speaker device 3 a is a speaker
device disposed on the driver's side of the instrument panel 2 a. Similarly, the speaker device 3b
is a speaker device disposed on the passenger seat side of the instrument panel 2a. The speaker
devices 3a and 3b are mounted in the instrument panel 2a, for example, such that the central
axis is parallel to the vertical direction toward the inside of the vehicle 2.
[0013]
Further, in the speaker system 1 illustrated in FIG. 1, the speaker device 4a is a speaker device
provided on the driver's seat side front door 2b, and the speaker device 4b is a speaker provided
on the passenger's seat side front door 2c. It is an apparatus. The speaker device 5a is a speaker
device provided to the driver's seat side rear door 2d, and the speaker device 5b is a speaker
device provided to the front passenger seat side rear door 2e. The speaker devices 4a, 4b, 5a, 5b
are mounted, for example, in corresponding doors such that the central axis is parallel to the
horizontal direction toward the inside of the vehicle 2.
[0014]
The arrangement position of the speaker device 10 in the vehicle 2 is not limited to the
arrangement position illustrated in FIG. 1. For example, the speaker device 10 may be provided
at the center position of the instrument panel 2a, or may be provided at the rear deck behind the
rear seat. Further, the speaker device 10 may be provided on a pillar on the driver's seat side of
the vehicle 2 and a pillar on the passenger's seat side.
[0015]
03-05-2019
5
FIG. 2 is a view for explaining the mounting state of the speaker device 3a mounted on the
driver's seat side in the instrument panel 2a. The speaker device 3a is mounted in the instrument
panel 2a such that the central axis Z2 is parallel to the vertical direction. The sound wave output
from the speaker device 3a is heard by, for example, a user who is seated at the driver's seat and
steers the steering wheel 2f. The position of the ear of the user seated in the driver's seat or the
like is the listening position of the sound wave output from the speaker device 3a attached to the
driver's seat side in the instrument panel 2a.
[0016]
As shown in FIG. 2, the listening position of the sound wave output from the speaker device 3a is
in a direction inclined from the central axis Z2 of the speaker device 3a. When listening in a
direction inclined from the central axis Z2 of the speaker device 3a, the sound quality
deterioration occurs due to the high frequency sound pressure level lowered by the cancellation
of the sound waves of the bands in opposite phase at the listening position. There is a risk.
[0017]
FIG. 3 is a diagram for explaining the reduction of the sound pressure level due to the inclination
from the central axis. FIG. 3 (1) is a view for explaining the direction of inclination of the speaker
device 10 with respect to the central axis, and FIG. 3 (2) is a diagram of the sound pressure level
of the sound wave output from the speaker device 10 due to the inclination from the central axis.
It is a figure explaining a fall.
[0018]
In FIG. 3 (1), the speaker device 10 has a diaphragm 11 and a drive unit 12. The drive unit 12 is
a unit for vibrating the diaphragm 11 in accordance with the sound wave signal input to the
speaker device 10 via the AVN machine or the like. The diaphragm 11 is a device that vibrates by
the drive control of the drive unit 12 and outputs (transmits) a sound wave to the user at the
listening position via air. The diaphragm 11 and the drive unit 12 are integrally attached via a
speaker frame of the speaker device 10 (not shown).
03-05-2019
6
[0019]
As shown in FIG. 3 (1), assuming that the central axis Z2 direction of the speaker device 10 is "0
degree" and the inclination angle from the central axis Z2 is used, the inclination direction is "30
degrees" direction, "60 degrees" direction It shall be expressed as When the central axis Z2
shown in FIG. 3 (1) is parallel to the vertical direction, the inclination direction in the "90
degrees" direction is a horizontal direction orthogonal to the central axis Z2.
[0020]
FIG. 3 (2) is a diagram showing a frequency characteristic in which the sound pressure level (dB)
of the sound wave output from the speaker device 10 is taken as a vertical axis and the
frequency (Hz) of the sound wave is taken as a horizontal axis. In FIG. 3 (2), a graph g1 indicated
by a solid line represents frequency characteristics of the sound wave in the central axis Z2
direction of FIG. 3 (1). Similarly, a graph g2 indicated by a broken line represents the frequency
characteristic of the sound wave in the direction of 30 degrees shown in FIG. 3 (1). Further, a
graph g3 indicated by an alternate long and short dash line indicates the frequency characteristic
of the sound wave in the 60 degree direction shown in FIG. 3 (1). The frequency range of the
sound wave output from the speaker device 10 is, for example, an audible band of 20 Hz to 20
kHz.
[0021]
As shown in FIG. 3 (2), the sound pressure level of the sound wave output from the speaker
device 10 tends to decrease as the inclination angle from the central axis increases. In addition,
the decreasing tendency of the sound pressure level is remarkable in the high frequency region.
For example, when the frequency characteristic of the sound wave in the central axis Z2 direction
is compared based on the graph g1, the sound pressure level decreases in the order of the
frequency characteristic in the 30 degree direction (graph g2) and the frequency characteristic in
the 60 degree direction (graph g3) I know what to do. Also, it can be seen that the frequency at
which the sound pressure level decreases becomes relatively lower as the inclination angle from
the central axis increases. A frequency range of, for example, 2 kHz to 20 kHz is exemplified as a
frequency band in which the sound pressure level is reduced when the graph g1 is used as a
reference.
03-05-2019
7
[0022]
FIG. 4 is a diagram for explaining the reduction of the sound pressure level of the sound wave
output from the speaker device 10. Z3 of FIG. 4 represents the circular opening surface of the
speaker apparatus 10, and the diameter of an opening surface becomes the diameter of the
diaphragm 11 which the speaker apparatus 10 has. The parts A1, B1 and C1 respectively
represent parts (positions) where an acoustic wave is output on the aperture surface. In the
opening surface of the speaker device 10, the part A1 represents a central part, the part C1
represents an end part, and the part B1 represents an intermediate part between the part A1 and
the part C1.
[0023]
Further, in FIG. 4, the wavelength d1 represents the sound wave length of a part of the sound
wave output from the portion A1 located on the central axis Z2 of the speaker device 10 in a
predetermined inclination direction (for example, 60 degrees). Similarly, the wavelengths d2 and
d3 respectively indicate the sound wave lengths of the sound waves output from the portions B1
and C1 in the predetermined inclination direction. Moreover, d1a represents the maximum
amplitude point about the wavelength d1 output from site ¦ part A1. Similarly, d2a and d3a
represent the maximum amplitude points for the wavelength d2 output from the portion B1 and
the wavelength d3 output from the portion C1, respectively.
[0024]
As shown by d1a, d2a, d3a in FIG. 4, in the direction inclined from the central axis Z2 of the
speaker device 10, a phase shift occurs between sound waves output from different portions A1,
B1, C1 of the diaphragm 11 Do. At the listening position where the sound waves output from the
speaker device 10 are heard, the sound waves having a phase shift will interfere with each other.
In the case where interference occurs, for example, cancellation of sound waves having different
phases (shifted by half wavelength) output from different portions A1, B1, and C1 of the
diaphragm 11 may occur. Therefore, at the listening position in the direction inclined from the
central axis Z2 of the speaker device 10, the sound pressure level of the sound wave output from
the speaker device 10 is lowered. At high frequencies that make up the sound wave, the length of
the wavelength is relatively short compared to the low frequency, so the sound pressure level
drop becomes noticeable.
03-05-2019
8
[0025]
<2. Speaker Device> (First Embodiment) FIG. 5 is a view for explaining phase interference of
sound waves output from the diaphragm 11 of the speaker device 10. As illustrated in FIG. 3A,
the diaphragm 11 of the speaker device 10 has a conical shape, and the surface of the diaphragm
11 inclines from the outer peripheral edge toward the central portion. In the following
description, the shape of the diaphragm 11 of the speaker device 10 will be described as being
inclined from the outer peripheral edge toward the central portion along the inclined surface of
the conical diaphragm 11.
[0026]
The explanatory view of FIG. 5 represents a cross-sectional view of the conical diaphragm 11
which inclines from the outer peripheral edge toward the central portion, passing through the
central axis Z2. A center cap 13 is provided at the center of the speaker device 10. The center
cap 13 is provided mainly for the purpose of preventing the inflow of dust and the like to the
drive unit 12.
[0027]
In FIG. 5, solid arrows A and C indicate sound waves output in a predetermined inclination
direction from the outer peripheral edge of the conical diaphragm 11, and solid arrows B indicate
a predetermined inclination from the central portion of the diaphragm 11. Represents a sound
wave output in a direction. On the outer peripheral edge of the diaphragm 11, the output
position A2 of the sound wave represented by the solid arrow A and the output position C2 of the
sound wave represented by the solid arrow C sandwich the central axis Z2 of the speaker device
10 opposite.
[0028]
As shown in FIG. 5, in the direction inclined from the central axis, at the time when the sound
wave is output from the diaphragm 11, a difference in distance due to the opening diameter of
the speaker device 10 occurs. For example, a distance difference L occurs at A2 and C2 on the
03-05-2019
9
outer peripheral edge of the diaphragm 11 facing each other across the central axis Z2. In the
case of listening in a direction inclined from the central axis of the speaker device 10, phase
interference of sound waves occurs with the above-mentioned difference in distance, and a
decrease in sound pressure level occurs.
[0029]
An example of a structure of the speaker apparatus 10 which concerns on FIG. 6 at this
embodiment is shown. In FIG. 6, a plan view in which the opening surface of the speaker device
10 according to the present embodiment is viewed in plan from the direction of the central axis
Z2 is illustrated. Moreover, in FIG. 6, the cross-sectional view of the G-G location in the plan view
is illustrated. In addition, in GG sectional drawing, the arrows B and C of the continuous line
represent the sound wave output from the diaphragm 11 in a predetermined ¦ prescribed
inclination direction, as FIG. 5 demonstrated. The arrow direction of the solid line is the listening
direction of the sound wave output from the speaker device 10 according to the present
embodiment.
[0030]
The speaker device 10 according to the present embodiment includes phase interference
suppression means for suppressing a decrease in sound pressure level in a direction inclined
from the central axis. The phase interference suppression means is configured, for example, as a
phase interference suppression plate 14 as shown in FIG. Examples of the material forming the
phase interference suppression plate 14 include resins such as ABS (acrylonitrile (Acrylonitrile),
butadiene (Butadiene), styrene (Styrene)) and the like. By using resin as the material of the phase
interference suppression plate 14, the manufacturing cost of the speaker device 10 can be
relatively suppressed. The phase interference suppression plate 14 illustrated in the plan view of
FIG. 6 is an example of a rectangular shape.
[0031]
As shown in the plan view of FIG. 6, the phase interference suppression plate 14 extends, for
example, from the outer peripheral edge of the circular diaphragm 11 toward the central portion
where the center cap 13 is provided. It is configured to cover a partial area. Moreover, as shown
to GG sectional drawing of FIG. 6, the phase interference suppression board 14 is comprised so
03-05-2019
10
that it may incline in parallel with the diaphragm 11 of conical shape.
[0032]
In the plan view of FIG. 6, it is assumed that the phase interference suppression plate 14
disposed so as to cover the surface of the diaphragm 11 is, for example, the position A2 on the
outer peripheral edge shown in FIG. In the speaker device 10 of the present embodiment, the
sound wave output from the area on the diaphragm 11 from the position A2 shown in FIG. 5
toward the central portion is shielded by the phase interference suppression plate 14. As a result,
sound waves are output from part of the area of the diaphragm 11.
[0033]
The vibration of the sound wave output from the region on the diaphragm 11 shielded by the
phase interference suppression plate 14 is, for example, visco-elastic (shielding property) of the
material in the process of propagating the material constituting the phase interference
suppression plate 14 , It is estimated that part of the vibration is converted to heat energy. For
this reason, in the state shielded by the phase interference suppression plate 14, the sound wave
output from the region on the diaphragm 11 corresponding to the shielding position, that is, the
vibration of the sound wave causing the sound pressure level reduction is the phase interference
suppression plate It will be attenuated by the shielding property of 14.
[0034]
In the attenuated sound wave, the amplitude level is relatively small, and hence the phase
interference to the sound wave C output from the other region on the diaphragm 11 is relatively
small. For example, as shown in the GG cross-sectional view of FIG. 6, the relative amplitude
levels of the sound waves output from the region on the diaphragm 11 covered by the phase
interference suppression plate 14 face each other across the central axis Z2. It is possible to
reduce the phase interference with the sound waves (sound waves output from between B and C)
output from the region on the vibrating plate 11 so as to be negligible.
[0035]
03-05-2019
11
As a result, as shown in the GG cross-sectional view of FIG. 6, in the direction inclined from the
central axis Z2, on the diaphragm 11 opposed to the shielding region of the phase interference
suppression plate 14 with the central axis Z2 interposed therebetween. Sound waves output from
the area are mainly output. At the listening position in the direction inclined from the central axis
Z2 of the speaker device 10 according to the present embodiment, the sound wave between B
and A that interferes with the sound wave output from between B and C is in an attenuated state,
so the reverse phase is It becomes possible to suppress the cancellation of the sound waves of
the band in which In the speaker device 10 according to the present embodiment, it is possible to
suppress the decrease in sound pressure level caused by phase interference at the listening
position in the direction inclined from the central axis Z2.
[0036]
In addition, the suppression effect of the sound pressure level fall in the phase interference
suppression board 14 works effectively also in the opposing side direction which opposes on the
area ¦ region in which the phase interference suppression board 14 was provided on both sides
of central axis Z2. FIG. 7 is a diagram for explaining suppression of the sound pressure level
decrease in the opposite side direction opposite to each other across the central axis Z2 in the
region where the phase interference suppression plate 14 is provided. A plan view of the opening
surface of the speaker device 10 as viewed in plan from the direction of the central axis Z2
shown in FIG. 7 is the same as FIG. Further, solid arrows B and C shown in the F-F cross-sectional
view of FIG. 7 are the same as in FIG. 6, and the solid arrow directions are the sound wave
listening directions.
[0037]
As shown in the F-F cross-sectional view of FIG. 7, the phase interference suppression plate 14 is
provided in the listening direction on the opposite side facing the center axis Z2 with respect to
the region where the phase interference suppression plate 14 is provided. Sound waves output
from the selected area will be shielded. In the state of being shielded by the phase interference
suppression plate 14, the sound wave output from the region on the diaphragm 11
corresponding to the shielding position is attenuated by the shielding characteristic of the phase
interference suppression plate 14. Therefore, with respect to the area where the phase
interference suppression plate 14 is provided, the central axis Z2 is interposed with respect to
the shielding region of the phase interference suppression plate 14 in the listening direction on
the opposite side facing with the central axis Z2 opposite thereto. A sound wave output from a
03-05-2019
12
region (for example, between B and C) on the opposing diaphragm 11 is mainly output.
[0038]
In the listening direction on the opposite side opposite to the area where the phase interference
suppression plate 14 is provided with the central axis Z2 interposed therebetween, for example,
the sound wave interfering with the sound wave output from between B and C is attenuated It is
possible to suppress the cancellation of sound waves in bands in opposite phase. In the speaker
device 10 according to the present embodiment, the reduction in sound pressure level is
suppressed also in the listening direction on the opposite side opposite to the region where the
phase interference suppression plate 14 is provided and the central axis Z2.
[0039]
(Phase Interference Suppression Plate) The shape of the phase interference suppression plate 14
provided in the speaker device 10 according to the present embodiment, even if it is a shape
other than a rectangular shape, of the sound pressure level reduction described with reference to
FIGS. It is possible to play a suppressing effect. Variations other than the rectangular shape of the
phase interference suppression plate 14 are illustrated in FIGS.
[0040]
FIG. 8 is a view showing an example of variations of the shape of the phase interference
suppression plate 14 other than the rectangular shape. In FIG. 8 (1), the top view which planarly
viewed the opening surface of the speaker apparatus 10 provided with the phase interference
suppression board 14 from the direction of central-axis Z2 and sectional drawing in alignment
with the diameter direction of an opening surface are illustrated. In FIG. 8 (2), the perspective
view of the state which combined the member 15 for vehicle attachment with the speaker
apparatus 10 shown to FIG. 8 (1) is illustrated. The vehicle attachment member 15 is attached to
the speaker frame of the speaker device 10. The speaker device 10 provided with the phase
interference suppression plate 14 has the instrument panel 2a, the driver's seat side front door
2b, the passenger's seat side front door 2c, the driver's seat via the vehicle attachment member
15 shown in FIG. It is attached and fixed to the side rear door 2d, the passenger side rear door
2e, etc.
03-05-2019
13
[0041]
As shown in FIGS. 8A and 8B, the shape of the phase interference suppression plate 14 is a
rectangular shape extending from the outer peripheral edge of the circular diaphragm 11 toward
the central portion where the center cap 13 is provided. is there. As shown in the cross-sectional
view of FIG. 8 (1), the phase interference suppression plate 14 is configured to be inclined
parallel to the conical diaphragm 11. However, the tip end portion 14 a of the phase interference
suppression plate 14 is provided with a U-shaped notch for avoiding interference with the
structure (center cap 13) included in the speaker device 10. The phase interference suppression
plate 14 has a U-shaped notch in the tip portion 14 a extending toward the central portion to
avoid interference with the center cap 13, thereby forming one of the surfaces near the central
portion of the diaphragm 11. It is possible to include and cover part areas. In the phase
interference suppression plate 14 shown in FIGS. 8 (1) and 8 (2), suppression of the decrease in
sound pressure level with respect to the sound wave output from the central portion of the
diaphragm 11 can be expected.
[0042]
FIG. 9 is a view showing an example of a variation in which the phase interference suppression
plate 14 has a fan-like shape (trapezoidal shape). FIG. 9 illustrates a plan view of the opening
surface of the speaker device 10 including the phase interference suppression plate 14 viewed in
plan from the direction of the central axis Z2. In the phase interference suppression plate 14
shown in FIG. 9, the width dimension at the outer peripheral edge of the diaphragm 11 is "W1",
and the width dimension of the tip portion 14a extending toward the central portion is "W2"
smaller than the width dimension W1. It has a fan shape (trapezoidal shape). The width
dimension W2 of the tip portion 14a may be configured to be equal to the diameter of the center
cap 13.
[0043]
The shape of the phase interference suppression plate 14 included in the speaker device 10 is,
for example, the frequency band of the sound wave that suppresses the sound pressure level
decrease, the material of the phase interference suppression plate 14, the shape of the
diaphragm 11 of the speaker device 10, and the speaker device It can be determined
experimentally according to the parameters such as 10 reproduction frequency characteristics.
03-05-2019
14
[0044]
For example, the manufacturer of the speaker device 10 measures the frequency characteristics
of the decrease in the sound pressure level in the inclination direction at the listening position of
the sound wave output from the speaker device 10 and the in-vehicle position where the speaker
device 10 is fixed.
Then, the manufacturer of the speaker device 10 changes the shape of the phase interference
suppression plate 14 according to the above parameters to measure the frequency characteristic,
and determines the shape effective for suppressing the sound pressure level reduction from the
measurement result. Just do it.
[0045]
Similarly, the manufacturer of the speaker device 10 can experimentally determine the relative
distance between the diaphragm 11 and the phase interference suppression plate 14 inclined
parallel to the diaphragm 11. The manufacturer of the speaker device 10 changes the relative
distance according to the parameters and the shape of the phase interference suppression plate
14 to measure the frequency characteristics, and determines the relative distance effective for
suppressing the sound pressure level reduction from the measurement result. And it is sufficient.
[0046]
Second Embodiment As described with reference to FIG. 5, in the direction inclined from the
central axis of the speaker device 10, at the time when a sound wave is output from the
diaphragm 11, the distance difference caused by the aperture diameter of the speaker device 10
is It will happen. The above-mentioned difference in distance between sound waves is maximized
between positions on the outer peripheral edge in the diametrical direction including the central
axis.
[0047]
FIG. 10 is a view for explaining the difference in distance caused by the opening diameter of the
03-05-2019
15
speaker device 10. In FIG. 10 (1), the top view which planarly viewed the opening surface of the
speaker apparatus 10 provided with the phase interference suppression board 14 from centeraxis Z2 direction is illustrated. In FIG. 10 (2), a cross-sectional view of a portion E-E in the plan
view shown in FIG. 10 (1) is exemplified. In FIG. 10 (3), a cross-sectional view taken along the
line HH in the plan view shown in FIG. 10 (1) is exemplified. The solid-line arrows shown in the
EE cross-sectional view of FIG. 10 (2) represent the sound waves output from the positions C3
and A3 on the outer peripheral edge, respectively. In addition, solid arrows shown in the HH
sectional view of FIG. 10 (3) represent the sound waves output from the positions C4 and A4 on
the outer peripheral edge, respectively.
[0048]
In the EE sectional view shown in FIG. 10 (2), the distance difference generated between the
sound waves outputted from the positions C3 and A3 on the outer peripheral edge is "L1".
Further, in the H-H cross-sectional view shown in FIG. 10 (3), the distance difference generated
between the sound waves output from the positions C4 and A4 on the outer peripheral edge is
L2 .
[0049]
As shown in FIG. 10 (1), the distance between the positions C3-A3 on the outer peripheral edge
of the diaphragm 11 is the largest (opening diameter), and from the distance between the
positions C4-A4 on the outer peripheral edge of the diaphragm 11 Too big. Therefore, the
relative relationship between the distance difference L1 generated between the sound waves
output from each of the positions C3 and A3 on the outer peripheral edge and the distance
difference L2 generated between the sound waves output from each of the positions C4 and A4
on the outer peripheral peripheral is , L1> L2.
[0050]
Since the distance difference is the phase difference between the sound waves between the
sound waves output from the speaker device 10, the phase difference between the sound waves
becomes larger as the distance difference is larger. That is, it can be said that the difference
between the sound waves output from the speaker device 10 is largest between the positions on
the outer peripheral edge in the diametrical direction including the central axis (between C3 and
03-05-2019
16
A3).
[0051]
FIG. 11 exemplifies the sound pressure level when the phase difference occurs. FIG. 11 is a graph
when sine waves of the same wavelength are synthesized with different phases. In FIG. 11, the
vertical axis represents the amplitude value, and the horizontal axis represents the wavelength of
the sine wave. Further, a curve indicated by a solid line represents a sine wave of the same
wavelength, and a curve indicated by a broken line represents a composite wave of sine waves
having phase differences.
[0052]
FIG. 11 (1) is a combination example in the case where the phase difference (phase shift) is small,
and FIG. 11 (2) is a combination example in the case where the phase difference is large. As
shown in FIGS. 11 (1) and 11 (2), when the phase difference is small, the amplitude value of the
composite wave obtained by combining the sine waves of the same wavelength becomes
relatively large, and when the phase difference is large. The amplitude value of a composite wave
obtained by combining sine waves of the same wavelength tends to be relatively small.
[0053]
That is, when sound waves of the same wavelength are output from the positions C3 and A3 on
the outer peripheral edge of the diaphragm 11, the phase difference between the sound waves is
maximum, so the degree of sound pressure level reduction caused by interference is the largest.
It can be said that On the other hand, when sound waves of the same wavelength are output from
the positions C4 and A4 on the outer peripheral edge of the diaphragm 11, the phase difference
between the sound waves is relatively small. For this reason, it can be said that the degree of the
sound pressure level reduction caused by the interference between the outputted sound waves
becomes relatively small.
[0054]
03-05-2019
17
In the speaker device 10 according to the second embodiment, in order to suppress a decrease in
sound pressure level caused by a distance difference which is maximum between positions on the
outer peripheral edge in the diameter direction including the central axis, two opposing ones
sandwiching the central axis The phase interference suppression plate 14 may be provided. In
the speaker device 10 according to the second embodiment, it is possible to suppress the
decrease in sound pressure level due to the difference in distance which is maximum between the
positions on the outer peripheral edge in the diametrical direction including the central axis.
[0055]
FIG. 12 illustrates an example of the configuration of the speaker device 10 according to the
second embodiment (hereinafter, also referred to as the present embodiment). In FIG. 12, the
speaker apparatus 10 provided with two phase interference suppression board 14 -1, 14-2 which
opposes on both sides of central axis Z2 is illustrated. In FIG. 12 (1), the top view which planarly
viewed the opening surface of the speaker apparatus 10 provided with two phase interference
suppression board 14 -1, 14-2 which opposes on both sides of central axis Z2 from the central
axis Z2 direction is illustrated. Be done. In FIG. 12 (2), the cross-sectional view along the diameter
direction of the opening surface of the speaker apparatus 10 shown in FIG. 12 (1) is illustrated.
[0056]
The speaker device 10 shown in FIG. 12 is an example in which, for example, the rectangular
phase interference suppression plate 14 shown in FIG. 6 is opposed to each other with the
central axis Z2 interposed therebetween. As shown in FIG. 12 (1), each of the phase interference
suppression plates 14-1 and 14-2 extends, for example, from the outer peripheral edge of the
circular diaphragm 11 toward the central portion where the center cap 13 is provided. To cover
a partial area of the surface of the diaphragm 11. Partial regions of the surface of the diaphragm
11 covered by the phase interference suppression plates 14-1 and 14-2 oppose each other with
the central axis Z2 interposed therebetween. Further, as shown in FIG. 12 (2), each of the phase
interference suppression plates 14-1 and 14-2 is configured to be inclined parallel to the conical
diaphragm 11.
[0057]
The dimension width W3 of the phase interference suppression plate 14-1 and the dimension
03-05-2019
18
width W4 of the phase interference suppression plate 14-2 may be equal or different. As
described with reference to FIGS. 8 and 9, the dimension width of the phase interference
suppression plates 14-1 and 14-2 is, for example, the frequency band of the sound wave that
suppresses the sound pressure level decrease, the material of the phase interference suppression
plate 14, It can be determined experimentally according to the shape of the diaphragm 11 of the
speaker device 10, parameters such as the reproduction frequency characteristic of the speaker
device 10, and the like.
[0058]
For example, the manufacturer of the speaker device 10 measures the frequency characteristics
of the in-vehicle position at which the speaker device 10 is mounted and fixed and the sound
pressure level decrease in the tilt direction at the listening position of the sound wave output
from the speaker device 10. Then, the manufacturer of the speaker device 10 changes the
dimension width of the phase interference suppression plates 14-1 and 14-2 in accordance with
the above parameters to measure the frequency characteristics, and is effective in suppressing
the sound pressure level reduction from the measurement result. It is sufficient to obtain a
typical dimensional width. The relative distance between the diaphragm 11 and the phase
interference suppression plates 14-1 and 14-2 inclined parallel to the diaphragm 11 can also be
determined in the same manner.
[0059]
(Phase Interference Suppression Plate) Also in the present embodiment, the shape of the phase
interference suppression plates 14-1 and 14-2 may be a shape other than the rectangular shape.
13 to 18 illustrate variations of the phase interference suppression plates 14-1 and 14-2
configured to face each other with the central axis Z2 interposed therebetween.
[0060]
FIG. 13 shows an example in which the phase interference suppression plate 14 shown in FIG. 8
is opposed to each other with the central axis Z2 interposed therebetween. As shown in FIG. 13,
the phase interference suppression plates 14-1 and 14-2 are configured to avoid interference
with the center cap 13 at the central portion of the speaker device 10. In addition, each front-end
¦ tip part in which the U-shaped notch of phase interference suppression board 14-1, 14-2 was
03-05-2019
19
provided closely̲contact ¦ adheres in the center part of the speaker apparatus 10. FIG. Also in
the variation shown in FIG. 13, as in FIG. 12, the dimension width W5 of the phase interference
suppression plate 14-1 and the dimension width W6 of the phase interference suppression plate
14-2 may be equal or different. It may be a dimension width.
[0061]
FIG. 14 is a configuration example in the case where the phase interference suppression plates
14-1 and 14-2 in close contact with each other at the center of the speaker device 10 shown in
FIG. 13 are integrated. Further, FIG. 15 is an example in which the fan-shaped (trapezoidal shape)
phase interference suppression plate 14 shown in FIG. 9 is configured to be opposed to each
other with the central axis interposed therebetween. Also in the variations shown in FIGS. 14 and
15, the dimensional width of the phase interference suppression plate 14-1 and the dimensional
width of the phase interference suppression plate 14-2 may be equal or different. Good. Each
dimension width corresponds to, for example, parameters such as the frequency band of the
sound wave suppressing the sound pressure level decrease, the material of the phase
interference suppression plate 14, the shape of the diaphragm 11 of the speaker device 10, and
the reproduction frequency characteristic of the speaker device 10. , Can be determined
experimentally.
[0062]
In FIG. 16, the phase interference suppression plate 14 shown in FIG. 8 is used as the phase
interference suppression plate 14-1, and the opposing side facing the center axis between is a
fan-shaped (trapezoidal shape) phase interference suppression plate 14- shown in FIG. It is an
example configured as two. In FIG. 16 (1), the top view which planarly viewed the opening
surface of the speaker apparatus 10 provided with the said phase interference suppression board
14-1, 14-2 is illustrated. In FIG. 16 (2), the perspective view of the state which combined the
member 15 for vehicle attachment with respect to the speaker apparatus 10 of FIG. 16 (1) is
illustrated.
[0063]
As shown in FIG. 16 (1), each of the phase interference suppression plates 14-1 and 14-2
extends, for example, from the outer peripheral edge of the circular diaphragm 11 toward the
03-05-2019
20
central portion provided with the center cap 13 To cover a partial area of the surface of the
diaphragm 11. Partial regions of the surface of the diaphragm 11 covered by the phase
interference suppression plates 14-1 and 14-2 face each other across the central axis. Each of
the phase interference suppression plates 14-1 and 14-2 is configured to be inclined in parallel
with the conical diaphragm 11.
[0064]
As shown in FIG. 16, the phase interference suppression plates 14-1 and 14-2 facing each other
across the central axis of the speaker device 10 can be configured to have mutually different
shapes. Also in the variation shown in FIG. 16, the shapes of the phase interference suppression
plates 14-1 and 14-2 can be experimentally obtained in the same manner as the other variations
described above. The combination of shapes may be determined according to parameters such as
the frequency band of the sound wave suppressing the sound pressure level decrease, the
material of the phase interference suppression plate 14, the shape of the diaphragm 11 of the
speaker device 10, and the reproduction frequency characteristic of the speaker device 10. .
[0065]
FIG. 17 shows the configuration in the case where the tip end portion 14-1a of one of the phase
interference suppression plates 14-1 and 14-2 is extended to the opposing region opposite to
each other across the central axis. It is an example. In FIG. 17 (1), a plan view of the opening
surface of the speaker device 10 in which the tip end portion 14-1a of the phase interference
suppression plate 14-1 is extended to the opposing region opposite to sandwich the central axis
And a cross-sectional view along the diametrical direction of the opening surface is illustrated. In
FIG. 17 (2), the perspective view of the state which combined the member 15 for vehicle
attachment with respect to the speaker apparatus 10 shown to FIG. 17 (1) is illustrated.
[0066]
As shown in FIGS. 17 (1) and 17 (2), the phase interference suppression plate 14-1 extends from
the outer peripheral edge of the circular diaphragm 11 toward the central portion where the
center cap 13 is provided. Then, the tip end portion 14-1a of the phase interference suppression
plate 14-1 is configured to cover a partial region of the surface of the diaphragm 11 near the
center portion on the opposite side facing and opposite to the center axis. The tip portion 14-1a
03-05-2019
21
of the phase interference suppression plate 14-1 is formed in a semicircular shape. Further, as
shown in the cross-sectional view of FIG. 17A, the phase interference suppression plate 14-1
inclines in parallel to the conical diaphragm 11, and the tip portion 14-1a of the phase
interference suppression plate 14-1 Is configured to be inclined parallel to the opposing
diaphragm 11 near the center portion where the center cap 13 is provided.
[0067]
In the speaker device 10, the configuration of the phase interference suppression plate 14-1 is
configured as shown in FIGS. 17 (1) and 17 (2), so that the sound pressure level decrease is
suppressed and the phase interference suppression plate 14-1 is formed. It is possible to
relatively suppress the material cost involved in The shape of the tip portion 14a of the phase
interference suppression plate 14-1 shown in FIGS. 17 (1) and 17 (2) may be a shape other than
a semicircular shape.
[0068]
FIG. 18 is an example in which the shape of the tip end portion 14a of the phase interference
suppression plate 14-1 shown in FIGS. 17 (1) and 17 (2) is configured as a rectangular shape.
FIG. 18 exemplifies a plan view of the opening surface of the speaker device 10 provided with
the phase interference suppression plate 14-1 in which the shape of the tip end portion 14a is
rectangular. The tip portion 14-1a of the rectangular phase interference suppression plate 14-1
is a partial region of the surface of the diaphragm 11 near the central portion on which the
center cap 13 is provided on the opposite side facing the center axis. It is configured to cover.
[0069]
Also in the variations shown in FIGS. 17 and 18, a configuration including the shape of the tip
portion 14-1a of the phase interference suppression plate 14-1 can be experimentally obtained
in the same manner as the other variations described above. Depending on the frequency band of
the sound wave suppressing the sound pressure level reduction, the material of the phase
interference suppression plate 14, the shape of the diaphragm 11 of the speaker device 10, the
reproduction frequency characteristic of the speaker device 10, etc. The shape and the partial
region on the opposite side covered by the phase interference suppression plate 14-1 may be
determined.
03-05-2019
22
[0070]
Third Embodiment The phase interference suppression plate 14 described in the first and second
embodiments, for example, rotationally moves the opening surface of the speaker device 10
along the outer peripheral edge of the diaphragm 11 in the circular outer peripheral direction. It
is possible to have a rotating mechanism. The speaker device 10 according to the third
embodiment (hereinafter, also referred to as the present embodiment) has a rotation mechanism,
and has an outer peripheral edge of the phase interference suppression plate 14 configured to
cover a partial region of the diaphragm 11 of the speaker device 10 It can be rotationally moved
in the direction, and can be attached and fixed in any inclination direction.
[0071]
FIG. 19 is a view for explaining the rotational movement of the phase interference suppression
plate 14 provided with the rotation mechanism of the present embodiment along the circular
outer peripheral direction of the speaker device 10. The phase interference suppression plate 14
described with reference to FIG. 8 is taken as an illustrative example of the phase interference
suppression plate 14 that can be rotationally moved along the circular outer circumferential
direction of the speaker device 10.
[0072]
In FIG. 19, there is illustrated a plan view of the speaker device 10 having the phase interference
suppression plate 14 rotationally moved along the circular outer peripheral direction, in which
the opening surface is planarly viewed. In FIG. 19, the phase interference suppression plate 14
extending from the outer peripheral edge of the circular diaphragm 11 toward the central
portion provided with the center cap 13 has, for example, the circular outer peripheral edge of
the speaker device 10 by the rotation mechanism. Move to rotate counterclockwise. The
rotational movement direction of the phase interference suppression plate 14 by the rotation
mechanism may be clockwise.
[0073]
03-05-2019
23
FIG. 20 illustrates an example of a rotation mechanism that rotationally moves the phase
interference suppression plate 14 along the circular outer peripheral direction of the speaker
device 10. In FIG. 20, a cross-sectional view of a portion A-A in the plan view of FIG. 19 is
illustrated. The rotation mechanism shown in FIG. 20 supports, for example, the phase
interference suppression plate 14 and supports the support structure 14 b and the support
structure 14 b that are rotationally moved along the circular outer peripheral direction of the
speaker device 10. It comprises the support member 10b movable along the groove and the
speaker frame 10a. The support structure 14b is attached to fit in the groove structure formed in
the support member 10b and the speaker frame 10a. The support member 10 b is connected to
the phase interference suppression plate 14. The support member 10b and the speaker frame
10a may be integrally formed.
[0074]
As shown in FIG. 20, for example, an elastic member K1 is provided on the circular outer
peripheral edge of the speaker frame 10a. The elastic member K1 is, for example, a member such
as rubber, resin, or elastomer. The convex structure 14c provided on the outer peripheral edge
side of the phase interference suppression plate 14 is an elastic member in a concave space
formed between the support member 10b and the elastic member K1 provided on the outer
peripheral edge of the speaker frame 10a. It is slidably held on K1.
[0075]
For example, an operator who attempts to rotationally move the phase interference suppression
plate 14 along the outer peripheral edge of the speaker device 10 presses the phase interference
suppression plate 14 in the direction indicated by the arrow Z4 in the figure, and provides the
same on the speaker frame 10a. The elastic member K1 is compressed in the direction of the
speaker frame 10a. The operator rotates the phase interference suppression plate 14 to the
intended fixed position of the outer peripheral edge of the speaker device 10 in a state where the
elastic member K1 is compressed, and releases the pressing of the phase interference
suppression plate 14.
[0076]
03-05-2019
24
In the state where the pressure is released, the convex structure 14c provided on the outer
peripheral side of the phase interference suppression plate 14 is between the support member
10b and the elastic member K1 by the repulsive force (elastic force) of the elastic member K1. It
is clamped in the formed concave space. The rotation mechanism illustrated in FIG. 20 allows the
phase interference suppression plate 14 to rotationally move on the circular outer peripheral
edge of the speaker device 10 and to hold it at the position intended by the operator. The
position on the outer peripheral edge of the speaker device 10 in which the phase interference
suppression plate 14 is held is, for example, a tilt position corresponding to the listening
direction of the sound wave output from the speaker device 10.
[0077]
FIGS. 21 and 22 illustrate an explanatory view in the case where the speaker device 10 of the
present embodiment is attached to the instrument panel 2a. As shown in FIG. 21, the opening
surface of the speaker device 10 mounted in the instrument panel 2 a is vertically upward. For
example, it is assumed that the mounting position of the speaker device 10 corresponds to the
speaker device 3a on the driver's seat side shown in FIG. The sound wave output from the
speaker device 10 has a predetermined inclination with respect to the listening direction of the
user seated at the driver's seat.
[0078]
In the instrument panel 2a of the vehicle 2, the position at which the speaker device 10 is
mounted and fixed may be limited due to the vehicle structure. When the mounting and fixing
position of the speaker device 10 is limited, it may be difficult to turn the phase interference
suppression plate 14 for suppressing the reduction of the sound pressure level in the inclination
direction in the sound wave listening direction.
[0079]
FIGS. 22A and 22B are top views of the speaker device 10 shown in FIG. 21 from the arrow
direction (upper surface side of the central axis Z2). The speaker device 10 shown in FIGS. 22 (1)
and 22 (2) includes the phase interference suppression plate 14 that rotationally moves along
the circular outer peripheral direction of the speaker device 10 described with reference to FIGS.
The speaker device 10 is mounted, for example, in the instrument panel 2 a by a vehicle
03-05-2019
25
mounting member 15.
[0080]
As shown in FIG. 22A, it is assumed that the mounting and fixing position of the speaker device
10 in the instrument panel 2a is limited. The sound pressure level reduction suppression
direction Z5 by the phase interference suppression plate 14 is a partial region direction of the
diaphragm 11 covered by the phase interference suppression plate 14 as shown in the figure,
and the phase interference suppression It is an area direction on the opposite side opposite to
the plate 14 with the central axis interposed therebetween.
[0081]
When the mounting and fixing position of the speaker device 10 to the vehicle 2 is limited, it
may be difficult to direct the sound pressure level reduction suppressing direction Z5 by the
phase interference suppressing plate 14 in the listening direction indicated by the listening
position Z1. .
[0082]
In the speaker device 10 having the rotation mechanism of the present embodiment, as shown in
FIG. 22 (2), the phase interference suppression plate 14 is rotationally moved along the circular
outer peripheral direction after being fixed to the vehicle 2 It becomes possible.
In the speaker device 10 having the rotation mechanism, after mounting and fixing to the vehicle
2, it becomes possible to turn the suppression effect direction Z5 of the sound pressure level
reduction by the phase interference suppression plate 14 in the listening direction indicated by
the listening position Z1. Even when the mounting position of the speaker device 10 is limited
due to the vehicle structure, the phase interference suppression plate 14 can suppress the sound
pressure level reduction.
[0083]
In FIGS. 21 and 22, the speaker device 10 attached and fixed to the instrument panel 2a of the
03-05-2019
26
vehicle 2 has been described. The effect of turning the sound pressure level reduction
suppression direction Z5 of the phase interference suppression plate 14 in the listening direction
by the rotation mechanism is, for example, the driver's side front door 2b, the front passenger's
side front door 2c, and driving shown in FIG. Even in the case of being attached and fixed in the
seat-side rear door 2d and the passenger-side rear door 2e, the same effect can be obtained. After
the speaker device is attached to the above location in the vehicle 2, the phase interference
suppression plate 14 is rotationally moved along the circular outer peripheral direction, so that
the sound pressure level decreases in the listening position direction of the user seated near the
above location Suppression effect direction Z5 can be directed.
[0084]
<3. Measurement Results of Frequency Characteristics> Hereinafter, FIGS. 23 to 29 illustrate
measurement results of frequency characteristics showing a change in sound pressure level in
the inclination direction from the central axis Z2 of the speaker device 10. FIG. The frequency
measurement was performed in an anechoic chamber with an input of the speaker device 10 of 1
W, an aperture diameter of 16 cm, and a frequency sweep range of 20 to 20000 Hz. The
distance between the microphone for measuring the sound wave output and the speaker device
10 was 1 m, the central axis direction was 0 degrees, and inclinations in 30 directions and 60
degrees in three directions were performed.
[0085]
The graphs of frequency characteristics shown in FIG. 23 to FIG. 29 represent the sound
pressure level (unit: dB) on the vertical axis and the frequency (unit: Hz) on the horizontal axis. In
FIG. 23 to FIG. 29, the frequency characteristic in the 0 degree direction (central axis direction) is
indicated by a solid line, and the frequency characteristic when inclined in the 30 degree
direction is broken line, and the frequency characteristic when inclined in the 60 degree
direction is one point. Represented by a dashed line.
[0086]
FIG. 23 shows frequency characteristics of the speaker device 10 without the phase interference
suppression plate 14. It can be seen that the measured sound pressure level decreases as the
inclination angle of the speaker device 10 increases. Further, in the speaker device 10 without
03-05-2019
27
the phase interference suppression plate 14, it is understood that the relative fluctuation range
of the sound pressure level due to the inclination change from the central axis direction is large
in the frequency range of 2000H to 10000 Hz. For example, in the frequency range of 9000 Hz
to 10000 Hz, the fluctuation range of the relative sound pressure level between 0 degree and 60
degrees is coarse 15 dB.
[0087]
FIG. 24 shows frequency characteristics measured for the phase interference suppression plate
14 shown in FIG. The width dimension of the outer peripheral edge of the diaphragm 11 of the
phase interference suppression plate 14 is 50 mm. FIG. 24 (1) shows the frequency characteristic
in the inclination direction covered by the phase interference suppression plate 14, and FIG. 24
(2) shows a partial region of the diaphragm 11 covered by the phase interference suppression
plate 14. 3 shows the frequency characteristics in the case of being inclined to the opposite side
opposite to sandwiching the central axis Z2.
[0088]
As shown in FIG. 24 (1), relative to the case where the phase interference suppression plate 14 is
not provided (FIG. 23), relative to the sound pressure level due to the inclination change from the
central axis direction in the frequency range of 2000H to 10000 Hz. It can be seen that the
fluctuation range is small (narrowed). For example, in the frequency range of 9000 Hz to 10000
Hz, it can be seen that the fluctuation range of the relative sound pressure level between 0
degree and 60 degrees is roughly 10 dB. Also in FIG. 24 (2), it can be seen that the same effect as
in FIG. 24 (1) can be obtained.
[0089]
Also, comparing the sound pressure level in the 60 ° direction of FIG. 23 representing the
frequency characteristics of the speaker device 10 without the phase interference suppression
plate 14 with the sound pressure level in the 60 ° direction of FIG. Comparing the sound
pressure levels in Fig. 24 (2) with approximately 5 dB at 3 kHz, the phase interference
suppression plate is compared with a speaker device that does not have the phase interference
suppression plate 14 and so on. It can be seen that the speaker device having the effect of
increasing the sound pressure level in the inclined direction can be obtained.
03-05-2019
28
[0090]
That is, as a result of the above effect, the sound pressure in the direction in which the phase
interference suppression plate 14 is attached is greater than the sound pressure level in the
direction in which the conventional speaker is inclined when the phase interference suppression
plate 14 is not attached. You can set the level high.
[0091]
FIG. 25 shows the frequency characteristics measured for the phase interference suppression
plate 14 shown in FIG.
The width dimension at the outer peripheral edge of the diaphragm 11 of the phase interference
suppression plate 14 is 40 mm, and the dimension width of the tip portion extending toward the
central portion is 20 mm.
FIG. 25 (1) shows the frequency characteristic in the inclination direction covered by the phase
interference suppression plate 14, and FIG. 25 (2) shows a partial region of the diaphragm 11
covered by the phase interference suppression plate 14. 3 shows the frequency characteristics in
the case of being inclined to the opposite side opposite to sandwiching the central axis Z2.
[0092]
Even when the phase interference suppression plate 14 has a fan-like shape shown in FIG. 9, as
in FIG. 24, in the frequency range of 2000 H to 10000 Hz, relative fluctuation in sound pressure
level due to inclination change from the central axis direction It can be seen that the effect of
narrowing the width can be obtained. Also, comparing the sound pressure level in the 60 °
direction of FIG. 23 representing the frequency characteristics of the speaker device 10 without
the phase interference suppression plate 14 with the sound pressure level in the 60 ° direction
of FIG. Compared to the speaker device without the phase interference suppression plate 14 such
as an increase of approximately 5 dB at ˜ 6 kHz, the speaker device having the phase interference
suppression plate has the effect of increasing the sound pressure level in the inclined direction I
understand that. In addition, it can be seen that the above effect is achieved also in the case
where the partial region of the diaphragm 11 covered by the phase interference suppression
plate 14 is inclined to the opposite side across the central axis Z2 with the central axis Z2
interposed therebetween.
03-05-2019
29
[0093]
Similar effects were obtained for the variation of the phase interference suppression plate 14
described in the second embodiment. In FIG. 26, the phase interference suppression plate 14
shown in FIG. 8 is used as the phase interference suppression plate 14-1, and the opposite side
facing the center axis between them is configured as the rectangular phase interference
suppression plate 14-2 shown in FIG. Indicates the frequency characteristics of the case. FIG. 27
shows frequency characteristics when the phase interference suppression plates 14-1 and 14-2
shown in FIG. 14 are integrated. The width dimension at the outer peripheral edge of the
diaphragm 11 of the phase interference suppression plates 14-1 and 14-2 was 40 mm.
[0094]
FIG. 28 shows the frequency characteristics when the phase interference suppression plates 14-1
and 14-2 shown in FIG. 16 are provided. FIG. 29 shows frequency characteristics when the phase
interference suppression plate 14-1 shown in FIG. 17 is provided. In FIG. 28, the width dimension
at the outer peripheral edge of the rectangular phase interference suppression plate 14-1 having
a U-shaped notch structure at the tip end is 50 mm, and the fan-shaped phase interference
suppression plate 14-1 The width dimension at the outer peripheral edge of the was 40 mm, and
the dimension width of the tip extending toward the center was 20 mm. Further, the width
dimension at the outer peripheral edge of the phase interference suppression plate 14-1 in FIG.
29 is 50 mm.
[0095]
As shown in FIG. 26 to FIG. 29, relative to the case where the phase interference suppression
plate 14 is not provided (FIG. 23), relative to the sound pressure level due to inclination change
from the central axis direction in the frequency range of 2000H to 10000 Hz. It can be seen that
the effect of making the fluctuation range smaller (narrower) can be obtained. Also, the sound
pressure level in the direction in which the frequency characteristics shown in FIGS. 26-29 are
inclined is higher than the sound pressure level in the direction in which the speaker apparatus
10 without the phase interference suppression plate 14 has frequency characteristics. It can be
seen that the effect of
03-05-2019
30
[0096]
(Modification) The speaker device 10 described above has been described as being mounted and
fixed in the instrument panel 2a in the vehicle 2 and the doors 2b to 2e of the vehicle 2. The
suppression effect of the sound pressure level reduction in the direction inclined from the central
axis direction of the speaker device 10 by the phase interference suppression plate 14 is not
limited to the inside of the vehicle 2. The speaker device 10 having the phase interference
suppression plate 14 of the present embodiment may be, for example, a speaker device installed
in an audio room or the like. The sound pressure level reduction can be suppressed by orienting
the phase interference suppression plate 14 with the position of the user's ear sitting on a
listening sheet or the like for sound wave listening provided in an audio room etc. as the listening
position direction. become.
[0097]
1 speaker system 2 vehicle 2a instrument panel 2b driver's seat front door 2c passenger's seat
front door 2d driver's seat rear door 2e passenger's seat rear door 2f steering wheel 3a, 3b, 4a,
4b, 5a, 5b, 10 Speaker Device 10a Speaker frame 10b Support member 11 Diaphragm 12 Drive
part 13 Center cap 14 Phase interference suppression plate 14a Tip part 14b Support structure
14c Convex structure 15 Vehicle mounting member K1 Elastic member
03-05-2019
31
1/--страниц
Пожаловаться на содержимое документа