JP2011035553

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 JP2011035553
An object of the present invention is to provide a vehicle presence notification device 1 capable
of notifying of the presence of a vehicle by a notification sound without using a large capacity
speaker. According to a vehicle presence notification device, speakers 2 to 4 constituting a
speaker array 5 emit notification sound to the air as ultrasonic waves, and a microcomputer 6 is
a speaker 3 at specific time intervals. The relay box 7 outputs a command to switch between the
positive electrode terminal and the negative electrode terminal. As a result, the vibration of the
vibrator of the speaker 3 repeats a state in which the phases of the vibration of the respective
vibrators of the speakers 2 and 4 coincide with each other and a state delayed by 180 °. For this
reason, without using a large capacity speaker, it is possible to emit a notification sound with
strong directivity in a plurality of directions to notify the presence of a vehicle. [Selected figure]
Figure 2
Vehicle presence notification device
[0001]
The present invention relates to a vehicle presence notification device for reporting the presence
of a vehicle.
[0002]
In recent years, vehicles driven by motors, such as electric vehicles and hybrid cars, are
increasing.
04-05-2019
1
And since driving travel by a motor is quiet compared with driving travel by an engine, there is a
possibility that a pedestrian etc. do not feel the existence of vehicles. Therefore, there is known a
vehicle presence notification device which attaches an audio speaker to a vehicle and generates
notification sound such as a pseudo engine sound to notify a pedestrian or the like in front of the
vehicle of the presence of the vehicle (for example, Patent Document 1) , 2).
[0003]
However, if it is intended to simply radiate the notification sound, the notification sound diffuses
to the surroundings and is attenuated, and since it is used outdoors, a large-capacity, waterproof
audio speaker is required, and It becomes difficult to mount and expensive. Further, when the
notification sound is emitted by the audio speaker, the notification sound may be heard even by a
passenger in the vehicle room or the like who does not need to feel the presence of the vehicle,
and these persons may feel uncomfortable.
[0004]
Patent Document 3 discloses a vehicle presence notification device that transmits a notification
radio wave together with a notification sound and receives the radio wave so that the presence of
the vehicle can be detected tactilely or visually. ing. However, in order to grasp the presence of a
vehicle by this vehicle presence notification device, it is necessary to equip the vehicle with a
transmitter of radio waves, and for pedestrians etc., it operates according to the reception of
radio waves and reception of radio waves. Since it is necessary to possess a perception device etc.
and there is a risk of forgetting possession of the device, it can not be said that it is a good
method.
[0005]
JP-A-10-201001 JP-A-2006-199110 JP-A-2007-182195
[0006]
The present invention has been made to solve the above-mentioned problems, and its object is to
provide a compact, waterproof structure without using a large-capacity speaker, and the
presence of a vehicle such as a passenger in a vehicle compartment. The present invention
provides a vehicle presence notification device capable of notifying the presence of a vehicle by a
04-05-2019
2
notification sound having directivity so that the notification sound can be heard even by those
who do not need to feel the danger of such people being uncomfortable. It is in.
[0007]
[Means for claim 1] The vehicle presence informing device according to claim 1 is for notifying of
the presence of a vehicle by a notification sound vibrating at a frequency of an audible area.
In addition, the vehicle presence notification device arranges at least two speakers that emit
notification sound on the carrier wave vibrating at the frequency of the ultrasonic wave region
and radiate them into the air such that the vibration directions of the respective transducers
become the same. The speaker array and phase control means for advancing or delaying the
phase of the sound wave emitted from the other speaker with respect to the phase of the sound
wave emitted from one of the two speakers.
[0008]
Thus, each speaker functions as a so-called "parametric speaker" in which the emitted sound
wave is self-demodulated at a position corresponding to the frequency of the carrier wave and
audible as a notification sound.
For this reason, it is possible to obtain an extremely directional notification sound and to provide
a small-sized waterproof structure, so that the presence of a vehicle can be notified by the
notification sound without using a large-capacity speaker.
[0009]
In addition, the phase control means makes it possible that the peaks of the sound waves emitted
from the two speakers coincide with each other in the direction in which the notification sound is
to be directed, and that the respective valleys coincide with each other. Can be controlled. As a
result, the notification sound can be emitted in various directions to notify the presence of the
vehicle.
04-05-2019
3
[0010]
[Means of claim 2] According to the vehicle presence informing device according to claim 2, the
vibrator of each of the two speakers vibrates in response to the application of the voltage or the
energization of the current to carry the notification sound as a carrier wave. Put on and radiate
into the air. Then, the phase control means switches the positive electrode terminal and the
negative electrode terminal of any one of the two speakers so that the sound wave radiated from
the other speaker with respect to the phase of the sound wave radiated from one speaker
Advance or retard the phase of
[0011]
Thereby, by switching between the positive electrode terminal and the negative electrode
terminal, the phases of the sound waves radiated from the two speakers become opposite to each
other. Therefore, by switching between the positive electrode terminal and the negative electrode
terminal, the notification sound can be directed in a predetermined direction determined by the
distance between the two speakers and the wavelength of the sound wave. Therefore, the
pointing direction can be switched easily.
[0012]
[Means of claim 3] According to the vehicle presence informing device of claim 3, the phase
control means switches the positive electrode terminal and the negative electrode terminal by the
relay or the switch. This means shows a specific mode in which the pointing direction of the
notification sound can be easily switched.
[0013]
(A) is a waveform diagram showing a notification sound, (b) is a waveform diagram showing a
carrier wave, (c) is a waveform diagram showing an ultrasonic wave obtained by modulating the
carrier wave based on the notification sound, d) is a waveform diagram showing an ultrasonic
wave in distortion, and (e) is a waveform diagram showing a notification sound after self
demodulation. (A) is a block diagram of the vehicle presence alerting apparatus before switching
04-05-2019
4
by a relay box, (b) is a block diagram of the vehicle presence alerting apparatus after switching
by a relay box. (A) is explanatory drawing which shows the amplification state of the sound wave
before switching by a relay box, (b) is explanatory drawing which shows the amplification state
of the sound wave after switching by a relay box. (A) is explanatory drawing which shows the
directivity direction of the alarm ¦ sound before switching by a relay box, (b) is explanatory
drawing which shows the directivity direction of the alarm ¦ sound after switching by a relay box.
[0014]
The vehicle presence notification device according to the embodiment notifies the presence of a
vehicle by a notification sound that vibrates at the frequency of the audible area. In addition, the
vehicle presence notification device arranges at least two speakers that emit notification sound
on the carrier wave vibrating at the frequency of the ultrasonic wave region and radiate them
into the air such that the vibration directions of the respective transducers become the same. The
speaker array and phase control means for advancing or delaying the phase of the sound wave
emitted from the other speaker with respect to the phase of the sound wave emitted from one of
the two speakers.
[0015]
In addition, the vibrators of the two speakers vibrate in response to the application of a voltage
or the energization of a current, so that a notification sound is carried on a carrier wave and
radiated into the air. Then, the phase control means switches the positive electrode terminal and
the negative electrode terminal of any one of the two speakers so that the sound wave radiated
from the other speaker with respect to the phase of the sound wave radiated from one speaker
Advance or retard the phase of Further, the phase control means switches the positive electrode
terminal and the negative electrode terminal by a relay or a switch.
[0016]
A STRUCTURE OF EXAMPLE The structure of the vehicle presence alerting ¦ reporting apparatus
1 of an Example is demonstrated based on drawing. The vehicle presence notification device 1 is
mounted on a vehicle such as an electric car or a hybrid car that may not sense the presence of a
pedestrian or the like due to the motor drive, for example, a pedestrian or the like around the
04-05-2019
5
vehicle To inform the presence of the vehicle.
[0017]
In addition, the vehicle presence notification device 1 places a notification sound (see FIG. 1 (a))
vibrating at a frequency in the audible area on a carrier wave (see FIG. 1 (b)) vibrating at a
frequency in the ultrasonic wave, as ultrasonic waves. It radiates into the air and uses the
principle of the so-called "parametric speaker". That is, the sound wave radiated from the vehicle
presence informing device 1 is an ultrasonic wave, and the ultrasonic wave is one obtained by
modulating the carrier wave based on the notification sound (see FIG. 1 (c)). By using the
ultrasonic waves, it is possible to exhibit great directivity in the direction of emitting the
notification sound.
[0018]
And while the ultrasonic wave emitted from the vehicle presence informing device 1 propagates
in the air, the nonlinear characteristic of air ( When air is restored from compression takes
longer time than when it is compressed (See FIG. 1 (d)), and self-demodulates at a position
corresponding to the frequency of the carrier wave to become a notification sound (see FIG. 1
(e)).
[0019]
For example, as shown in FIG. 2, the vehicle presence notification device 1 supplies power to a
speaker array 5 including three speakers 2 to 4 and respective transducers (not shown) of the
speakers 2 to 4, A microcomputer 6 for controlling the operation of each vibrator and a relay box
7 for switching between the positive terminal and the negative terminal of the speaker 3 are
provided.
[0020]
The speakers 2 to 4 constituting the speaker array 5 convert an electrical signal such as a
voltage input to each of the transducers into mechanical vibration, and vibrate at a frequency in
the ultrasonic region by the mechanical vibration. It generates sound waves.
The vibrator that generates such a sound wave is, for example, two electrodes arranged at
04-05-2019
6
predetermined spaces, a piezoelectric element having one end as a free end, and the other end as
a fixed end.
[0021]
When the vibrator is composed of two electrodes, the Coulomb force is generated or eliminated
between the two electrodes by repeating the voltage application and the voltage application
cancellation between the two electrodes. By the generation and disappearance of the one
electrode, it is possible to vibrate the one electrode to generate a sound wave.
In addition, when the vibrator is a piezoelectric element, by repeating voltage application to and
release from the piezoelectric element, an expansion force is generated or disappears in the
piezoelectric element itself. The free end of the piezoelectric element can be vibrated to generate
an acoustic wave.
[0022]
In the speakers 2 to 4, for example, the vibration directions of the respective vibrators are
arranged to be the same, and the respective vibrators are arranged on the same straight line
perpendicular to the vibration direction. Furthermore, the speakers 2 to 4 are arranged such that
the distance between the respective transducers of the speakers 2 and 3 is equal to the distance
between the respective transducers of the speakers 3 and 4.
[0023]
The microcomputer 6 has a known structure including a CPU having a control function and an
arithmetic function, various storage devices such as a ROM and a RAM, an input device, an
output device and the like. Further, the microcomputer 6 is outputted from an oscillator 10
generating an electric signal oscillating at a frequency in the ultrasonic region, a modulator 11
modulating the electric signal generated by the oscillator 10 based on the waveform of the
notification sound, and the modulator 11 Are provided so as to have the function of an amplifier
12 which amplifies the electrical signal to the extent that the speakers 2 to 4 can be driven.
04-05-2019
7
[0024]
Further, as described later, the microcomputer 6 has a function of phase control means 14 for
advancing or delaying the phase of the sound wave emitted from the speaker 3 with respect to
the phase of the sound wave emitted from the speaker 2, for example. The relay box 7 described
later also has the function of the phase control means 14. The relay box 7 switches between a
positive electrode terminal and a negative electrode terminal for supplying electric power to the
vibrator of the speaker 3, operates according to a command from the microcomputer 6, and
operates the positive electrode terminal and the negative electrode terminal of the speaker 3.
Switch.
[0025]
Then, the phase control means 14 changes the directivity of the notification sound by making the
phases of the emitted sound waves different between the speakers 2 and 3 and also different
between the speakers 3 and 4. For example, before the positive electrode terminal and the
negative electrode terminal are switched in the speaker 3 (see FIG. 2A), the phases of the sound
waves radiated are the same between the speakers 2 and 3 and are the same between the
speakers 3 and 4 I assume.
[0026]
In this case, as shown in FIG. 3A, the sound waves radiated from each of the speakers 2 to 4 in
the direction in which the respective transducers of the speakers 2 to 4 vibrate, that is, in the
direction toward the front of the speaker array 5 Peaks coincide, and valleys of sound waves
emitted from each coincide. As a result, the sound wave is amplified in the direction toward the
front of the speaker array 5, and the notification sound that has been self-demodulated is heard
loud, so the notification sound is directed in the direction toward the front of the speaker array 5.
[0027]
Then, after the positive electrode terminal and the negative electrode terminal are switched in
the speaker 3 (see FIG. 2B), the vibration of the vibrator of the speaker 3 has a phase 180
relative to the vibration of the respective vibrators of the speakers 2 and 4 Since it is delayed by
°, the phases of the emitted sound waves differ by 180 ° between the speakers 2 and 3 and
04-05-2019
8
also by 180 ° between the speakers 3 and 4.
[0028]
For this reason, as shown in FIG. 3B, in the direction toward the front of the speaker array 5, the
peak of the sound wave emitted from the speaker 2 matches the valley of the sound wave
emitted from the speaker 3 The valleys of the emitted sound waves coincide with the peaks of
the sound waves emitted from the speaker 4.
As a result, in the direction toward the front of the speaker array 5, the sound waves cancel each
other without being amplified.
[0029]
On the other hand, for example, the peaks of the sound waves emitted from the speakers 2 to 4
coincide with each other in the direction inclined by θ from the direction toward the front of the
speaker array 5, and the valleys of the sound waves emitted from each Match Here, if θ
represents the distance between the respective transducers of the speakers 2 and 3 (the distance
between the respective transducers of the speakers 3 and 4) as d and the wavelength of the
sound wave is λ, the relationship of Equation 1 below Meet. [Expression 1] d · sin θ = λ / 2
[0030]
As a result, in the direction inclined by θ from the direction toward the front of the speaker
array 5, the self-demodulated notification sound can be heard loudly, and the notification sound
is directed in the direction inclined by θ from the direction toward the front of the speaker array
5 . Therefore, for example, when the numerical value obtained by multiplying d by the square
root of 2 coincides with λ, the positive terminal and the negative terminal of the speaker 3 are
switched and then inclined 45 ° from the direction toward the front of the speaker array 5 In
the direction, the self-demodulated notification sound is heard loudly, and the notification sound
is directed in a direction inclined 45 ° from the direction toward the front of the speaker array
5.
04-05-2019
9
[0031]
Then, the microcomputer 6 outputs a command for switching between the positive electrode
terminal and the negative electrode terminal in the speaker 3 to the relay box 7 at specific time
intervals to switch the directivity direction of the notification sound. The direction inclined by θ
from the direction toward the front of the speaker array 5 is, as shown in FIG. 4, a direction
inclined by θ from the symmetry axis with the direction toward the front of the speaker array 5
as the symmetry axis. There are two directions, that is, a direction inclined by θ in the
counterclockwise direction.
[0032]
Therefore, the directional direction of the notification sound is one direction (see FIG. 4A) only in
the direction toward the front of the speaker array 5 and a direction inclined by θ from the
direction toward the front of the speaker array 5 clockwise, And, it switches between two
directions (refer to FIG. 4B) in a direction inclined by θ in the counterclockwise direction.
[0033]
[Effects of the Embodiment] According to the vehicle existence notification device 1 of the
embodiment, the speakers 2 to 4 constituting the speaker array 5 respectively put the
notification sound on the carrier wave vibrating at the frequency of the ultrasonic region and use
it as an ultrasonic wave The microcomputer 6 emits to the air, and outputs a command for
switching between the positive electrode terminal and the negative electrode terminal in the
speaker 3 to the relay box 7 at specific time intervals.
[0034]
As a result, the vibration of the vibrator of the speaker 3 repeats a state in which the phases of
the vibration of the respective vibrators of the speakers 2 and 4 coincide with each other and a
state delayed by 180 °.
Therefore, the directional direction of the notification sound is between one direction toward the
front of the speaker array 5 and two directions inclined by θ from the direction toward the front
of the speaker array 5 (θ satisfies the relationship of Equation 1). It can be switched.
04-05-2019
10
[0035]
According to the above, it is possible to notify the presence of a vehicle by a highly directional
notification sound without using a large-capacity speaker, and to notify the presence of a vehicle
by emitting a notification sound in at least three directions.
In addition, the directivity of the notification sound can be changed with a simple configuration,
such as switching between the positive electrode terminal and the negative electrode terminal by
the relay box 7.
[0036]
[Modification] According to the vehicle existence notifying apparatus 1 of the embodiment, the
positive electrode terminal and the negative electrode terminal are switched by the relay box 7.
However, the positive electrode terminal and the negative electrode terminal may be switched by
a switch. Further, instead of switching the positive electrode terminal and the negative electrode
terminal by relays or switches, the microcomputer 6 alone constitutes the phase control means
14 and controls the phase of the electric signal supplied to the vibrators of the speakers 2 to 4
The directivity of the notification sound may be changed.
[0037]
Further, the configuration of the speaker array 5 is not limited to the aspect of the embodiment.
For example, the speaker array 5 may be configured by only two speakers 2 and 3, and four or
more speakers are linearly arranged to be a speaker The array 5 may be configured, or a
plurality of speakers may be two-dimensionally arranged to configure the speaker array 5.
[0038]
1 Vehicle Presence Informing Device 2 Speaker 3 Speaker 4 Speaker 5 Speaker Array 7 Relay
Box 14 Phase Control Means
04-05-2019
11