JP7290438B2 - Vehicle proximity notification device - Google Patents

Description

The present invention relates to an approaching vehicle audible system, and in particular, an approaching vehicle audible system that uses a vibration plate that uses resonance characteristics to satisfy regulations regarding the notification sound when a vehicle is approaching, and realizes miniaturization and cost reduction of the entire system. Regarding.

Conventional vehicles are mainly of the type that runs using an engine as a driving source, and pedestrians and others have been able to recognize vehicles approaching from behind or from blind spots by the engine sounds emitted by the vehicles. However, in recent years, there are vehicles that can run without using an engine, such as electric vehicles and hybrid vehicles, and these vehicles do not emit engine noise. There is a problem that makes it difficult to recognize.

Therefore, in order to solve the above problem, various countries are currently enacting regulations to address the above problem by having vehicles that can run without using an engine, such as electric and hybrid vehicles, emit a notification sound. progressing. In addition, it is required to output a notification sound including a sound pressure equal to or higher than a specified value with respect to the notification sound emitted from the vehicle that can run without using the engine.

For example, according to Japanese regulations, vehicles that can run without using the above engine must use two frequency bands out of the frequency bands obtained by dividing 160 Hz to 5 kHz into 16 divisions of 1/3 octave from start to 20 km/h. It is necessary to output sound pressure above the specified value.

A structure shown in FIG. 4 is known as a vehicle 101 equipped with a conventional vehicle approach audible device 100 . FIG. 4 is a side view illustrating a conventional approaching vehicle audible system 100. As shown in FIG.

As shown in FIG. 4, an approaching vehicle audible system 100 for a vehicle 101 mainly has an arithmetic unit 102 and a speaker 103 . In the vehicle approaching notification device 100, the arithmetic unit 102 generates a predetermined notification sound signal, and the notification sound based on this notification sound signal is emitted outside the vehicle via the speaker 103. FIG. A pedestrian or the like can recognize that the vehicle 101 is approaching by recognizing the notification sound from the vehicle 101 (see Patent Document 1, for example).

JP 2016-179802 A

As described above, the computing unit 102 of the vehicle approaching audible system 100 has a vehicle environment computing section, a sound control section, and a sound output section. The sound output unit has a function of amplifying the notification sound signal generated by the mixer, and inputs the amplified notification sound signal to the speaker 103 . The speaker 103 emits a notification sound based on the notification sound signal to the outside of the vehicle to inform pedestrians and the like of the presence of the vehicle.

However, in the vehicle approaching notification device 100, the sound output section of the arithmetic unit 102 needs to amplify the notification sound signal so that the sound pressure is equal to or higher than the specified value of the Japanese law, so the sound output section becomes large. In addition, it becomes difficult to secure a mounting place for the sound output unit, and the manufacturing cost increases.

Also, the approaching vehicle notification device 100 emits the notification sound through the speaker 103 toward the outside of the vehicle. Here, when the speaker 103 is arranged in front of the right side or in front of the left side of the vehicle 101, pedestrians on the side where the speaker 103 is arranged can easily recognize the notification sound, but pedestrians on the opposite side of the arrangement position may etc. is far from the speaker 103, and there is a problem that it is difficult to recognize the notification sound.

On the other hand, in order to solve the problem due to the location of the speaker 103, it is conceivable to increase the notification sound emitted from the speaker 103. FIG. However, with this countermeasure, as described above, it is necessary to further amplify the notification sound signal, leading to an increase in the size of the sound output unit, making it difficult to secure a mounting location for the sound output unit, and increasing the manufacturing cost. There is a problem of

In addition, in order to solve the problem due to the location of the speaker 103, it is conceivable to arrange the vehicle approach audible device 100 including the speaker 103 in front of the left and right sides of the vehicle 101. FIG. However, with this countermeasure, there are two approaching vehicle audible devices 100, which makes it difficult to secure a mounting location and increases the manufacturing cost.

The present invention has been made in view of the above circumstances, and uses a diaphragm that uses resonance characteristics to satisfy the regulations for notification sounds when a vehicle is approaching, and to reduce the size and cost of the entire device. An object of the present invention is to provide a vehicle approach notification device.

An approaching vehicle audible device according to the present invention is a vehicle approaching audible device that generates a notification sound for notifying surroundings of an approaching vehicle, is attached to the front portion of the vehicle, and resonates at a first specific frequency. and a second vibration plate, which is a front portion of the vehicle, is mounted at a distance from the first vibration plate, and resonates at a second specific frequency that is a lower frequency band than the first specific frequency. and the first diaphragm and the second diaphragm are respectively vibrated to generate a first sound from the first diaphragm and a second sound from the second diaphragm and an electric vibrating member that generates the first sound and the second sound having a predetermined sound pressure or higher as the notification sound at the same time .

Further, in the approaching vehicle audible system of the present invention, the electric vibrating member repeatedly vibrates the first diaphragm at the first specific frequency to generate the first sound having a sound pressure equal to or higher than the predetermined sound pressure. and repeatedly vibrating the second diaphragm at the second specific frequency to generate the second sound having a sound pressure equal to or higher than the predetermined sound pressure.

In the approaching vehicle audible system of the present invention, the first diaphragm and the second diaphragm are attached to the front grille of the vehicle at both ends in the longitudinal direction so as to vibrate. It is characterized by

Further, in the approaching vehicle audible system of the present invention, the first diaphragm and the second diaphragm are arranged side by side in the height direction of the vehicle, and a set of the first diaphragm and the second diaphragm is arranged. 2 are mounted symmetrically with respect to the center line of the vehicle in the vehicle width direction.

Also, in the approaching vehicle audible system of the present invention, the first diaphragm and the second diaphragm are formed of a material softer than that of the front grille.

The approaching vehicle audible device of the present invention includes a first diaphragm mounted on the front part of a vehicle and resonating at a first specific frequency, and a front part of the vehicle mounted in the vicinity of the first diaphragm. , a second diaphragm that resonates at a second specific frequency that is a lower frequency band than the first specific frequency, and vibrates the first diaphragm and the second diaphragm, respectively, and vibrates from the first diaphragm and an electric vibrating member that generates a first sound and a second sound from the second diaphragm, and the notification sound includes the first sound and the second sound having a predetermined sound pressure or more. contains. With this structure, even if the vehicle is capable of running without using an engine, it is possible to inform pedestrians around the vehicle that the vehicle is approaching by means of the notification sound. By including the second sound in the low frequency band in the notification sound, the approach of the vehicle can be notified even to elderly people who have difficulty hearing the sound in the high frequency band.

Further, in the approaching vehicle audible device of the present invention, the electric vibrating member repeatedly vibrates the first diaphragm at the first specific frequency to generate the first sound having a predetermined sound pressure or more, A second sound having a predetermined sound pressure or higher is generated by repeatedly vibrating the second diaphragm at a second specific frequency. With this structure, it is possible to reduce the size of the sound output unit, make it easier to secure a mounting place for the sound output unit, and prevent an increase in the manufacturing cost of the sound output unit.

Further, in the approaching vehicle audible system of the present invention, the first diaphragm and the second diaphragm are attached to the front grille of the vehicle at both ends in the longitudinal direction so as to vibrate. This structure makes it easy to secure a mounting location for the vehicle approach audible device.

Further, in the approaching vehicle audible device of the present invention, the first diaphragm and the second diaphragm are arranged side by side in the height direction of the vehicle, and the pair of the first diaphragm and the second diaphragm are , are mounted symmetrically with respect to the center line in the width direction of the vehicle. With this structure, the notification sound can be reliably transmitted to both the left and right sides of the vehicle, and the size of the sound output unit can be reduced.

Further, in the approaching vehicle audible system of the present invention, the first diaphragm and the second diaphragm are made of a softer material than the front grille. With this structure, the first and second diaphragms are prevented from absorbing vibrations by the front grille, and can stably resonate at the first and second specific frequencies, respectively.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a front view illustrating a vehicle equipped with an approaching vehicle audible device, and FIG. 1B is a block diagram illustrating the approaching vehicle audible device according to an embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS It is (A) front view, (B) graph explaining the vehicle approach alerting|reporting apparatus which is one Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is (A) front view, (B) top view explaining the vehicle approach audible device which is one Embodiment of this invention. It is a side view explaining the conventional vehicle approach alerting device.

A vehicle approach audible device 10 according to an embodiment of the present invention will be described in detail below with reference to the drawings. In the description of the present embodiment, in principle, the same reference numbers are used for the same members, and repeated descriptions are omitted. In the following description, the vertical direction indicates the height direction of the vehicle 11, the horizontal direction indicates the vehicle width direction when the vehicle 11 is viewed from the front, and the front-rear direction indicates the length direction of the vehicle 11.

FIG. 1A is a front view illustrating a vehicle 11 equipped with an approaching vehicle audible system 10 of this embodiment. FIG. 1B is a block diagram for explaining the vehicle approach audible system 10 of this embodiment. FIG. 2A is a front view illustrating the first and second diaphragms 16 and 17 of the vehicle approach audible system 10 of this embodiment. FIG. 2B is a graph for explaining the notification sound emitted from the approaching vehicle notification device 10 of this embodiment. FIG. 3A is a front view illustrating the first and second diaphragms 16 and 17 of the vehicle approach audible system 10 of this embodiment. FIG. 3B is a top view for explaining a sound pressure measurement test of the vehicle 11 equipped with the vehicle approach audible system 10 of this embodiment.

As shown in FIG. 1A, a vehicle 11 is a vehicle that can run without using an engine, such as an electric vehicle, a hybrid vehicle, or a fuel vehicle. For example, according to Japanese regulations, the vehicle 11 that can run without using the above-mentioned engine must have two frequency bands in the frequency band obtained by dividing 160 Hz to 5 kHz into 16 every 1/3 octave from the start to 20 km / h. It is necessary to emit sound pressure above the specified value within the frequency band. Although the details will be described later, in the vehicle approach audible device 10 (see FIG. 1B) provided in the vehicle 11, the first and second diaphragms 16 , 17 resonate at different first or second specific frequencies, respectively. By resonating, the first and second diaphragms 16 and 17 simultaneously emit a notification sound having a predetermined sound pressure or more, thereby informing pedestrians around the vehicle 11 that the vehicle 11 is approaching. can be done.

As illustrated, on the front side of the vehicle 11, a front hood 12, a front bumper 13, a front grille 14, and the like are assembled to the vehicle body. A pair of headlights 15 for illuminating the front of the vehicle 11 above the front bumper 13 is assembled to the vehicle body at both ends in the vehicle width direction of the vehicle 11 .

The first and second diaphragms 16 and 17 are attached to the front grille 14 below the emblem 18 and aligned in the height direction of the vehicle 11 . An electric vibration member 23 (see FIG. 1B) is attached to the rear side of each of the first and second diaphragms 16 and 17, and is used as a speaker for the approaching vehicle audible system 10 (see FIG. 1B). be done. The first and second diaphragms 16 and 17 are arranged at the center of the front grille 14, that is, at the center of the vehicle 11 in the vehicle width direction. The notification sound is transmitted substantially uniformly to both the left and right sides in the vehicle width direction.

As shown in FIG. 1B, the approaching vehicle audible device 10 mainly includes a sound control unit 21, a sound output unit 22, an electric vibration member 23, a first diaphragm 16, and a second diaphragm. 17 and . Then, in the approaching vehicle notification device 10, the first and second diaphragms 16 and 17 are appropriately vibrated according to the detection signal from the vehicle state detection unit 19 of the vehicle 11, and the notification sound suitable for the above regulations is generated. is emitted outside the vehicle.

The sound generation control section 21 has a microprocessor for performing various calculations, and a rewritable non-volatile memory for storing software and the like for causing the microprocessor to execute each process. The sound control unit 21 then generates a notification sound signal based on the information input from the vehicle state detection unit 19 and inputs the generated notification sound signal to the sound output unit 22 .

Here, in the nonvolatile memory, at least a first sound signal having a first specific frequency to be input to the first diaphragm 16 and a second sound signal having a second specific frequency to be input to the second diaphragm 17 are stored. are stored. Then, the sound generation control section 21 generates a notification sound signal including at least the first sound signal and the second sound signal. Incidentally, when the sound output unit 22 is separately installed with respect to the first and second diaphragms 16 and 17, the sound generation control unit 21 outputs a notification sound signal including the first sound signal, A notification sound signal including the second sound signal may be generated and input to the individual sound output unit 22 .

The sound output unit 22 is a so-called amplifier that amplifies the notification sound signal input from the sound control unit 21 . Then, the notification sound signal amplified by the sound output unit 22 is input to the electric vibration member 23, and the electric vibration member 23 vibrates the first and second diaphragms 16 and 17 to generate the notification sound. It is emitted to the outside of the vehicle 11 . The electric vibration member 23 is an electric member that vibrates the first and second diaphragms 16 and 17, and is, for example, a piezoelectric diaphragm.

The vehicle state detection unit 19 detects the running state of the vehicle 11 , for example, detects the vehicle speed of the vehicle 11 and inputs the detection signal to the sound generation control unit 21 . Specifically, the vehicle state detection unit 19 monitors the vehicle speed meter of the vehicle 11 and detects whether or not the vehicle 11 is in a state of emitting a notification sound in accordance with the above regulations. Then, the sound control unit 21 generates a notification sound signal by receiving a detection signal representing a state of emitting a notification sound from the vehicle state detection unit 19, and controls the first and second diaphragms as described above. A notification sound is emitted from 16, 17 to the outside of the vehicle.

FIG. 2A shows the front grille 14 of the vehicle 11 in an enlarged manner, and the dashed line indicates the centerline CL of the vehicle 11 in the vehicle width direction. The first and second diaphragms 16 and 17 are arranged in parallel in the height direction of the vehicle 11 so as to be symmetrical with respect to the center line CL. The first and second diaphragms 16 and 17 are made of, for example, thermoplastic resin such as polyethylene, polypropylene, etc., are easily flexed, and easily vibrate when subjected to vibration from the electric vibration member 23 . there is

As illustrated, the first and second diaphragms 16 and 17 are supported by the front grille 14 at both ends in the longitudinal direction (the width direction of the vehicle 11) so as to vibrate. . The first and second diaphragms 16 and 17 are supported by the front grille 14 at the same height. Also, the front grille 14 is made of a harder material than the first and second diaphragms 16 and 17 . With this structure, the vibrations of the first and second diaphragms 16 and 17 are prevented from being absorbed by the front grille 14, and can stably resonate at the first or second specific frequency, respectively. .

As shown in FIG. 2B, the first diaphragm 16 has a structure that resonates in a high frequency band, and its first specific frequency is, for example, 1.6 kHz. On the other hand, the second diaphragm 17 has a structure that resonates in a low frequency band, and its second specific frequency is, for example, 800 Hz.

As described above, when the vehicle 11 is running at a speed of 20 km/h or less, the approaching vehicle audible device 10 emits a notification sound. and a second sound in a low frequency band produced by the second diaphragm 17 . Elderly people tend to have difficulty hearing the first sound in the high frequency band, but can recognize the approach of the vehicle 11 by hearing the second sound in the low frequency band. On the other hand, young people can easily hear the first sound in the high frequency band and can recognize the approach of the vehicle 11 .

Here, the following formula 1 is given as a relational expression of the resonance frequency f.
[Formula 1] f=1/2π×(k/m) ^1/2
f (Hz) is the resonance frequency f of each of the first and second diaphragms 16 and 17, and k (N/m) is each spring constant of the first and second diaphragms 16 and 17 and m (kg) is the mass of each of the first and second diaphragms 16 and 17 .

In this embodiment, the first and second diaphragms 16 and 17 are molded from the same material in order to reduce the manufacturing cost of the vehicle 11 . As shown in FIG. 2A, the first and second diaphragms 16 and 17 are, for example, plate-shaped, respectively. , the thickness is the same, and the length L1 in the lateral direction (height direction of the vehicle 11) is also the same. On the other hand, the length L2 of the second diaphragm 17 in the longitudinal direction (the vehicle width direction of the vehicle 11) is approximately twice the length L3 of the first diaphragm 16 in the longitudinal direction (the vehicle width direction of the vehicle 11). It has become.

The shape of the first and second diaphragms 16 and 17 is one example. The materials used for the first and second diaphragms 16 and 17 each have their own unique natural frequencies. By adjusting the materials used, the first and second diaphragms 16 and 17 The shape of 17 can be arbitrarily changed in design.

As described above, Japanese regulations require that a notification sound including sound with a sound pressure of 45 dB or more, for example, 45 dB or more, is emitted in two frequency bands. Therefore, in this embodiment, the first diaphragm 16 is designed to resonate at 1.6 kHz, and the second diaphragm 17 is designed to resonate at 800 Hz.

Then, the electric vibrating member 23 (see FIG. 1B) is continuously input with the small notification sound signal of the first or second specific frequency, and the electric vibrating member 23 vibrates the first or second The first and second diaphragms 16 and 17 are repeatedly vibrated at a specific frequency of . Then, the first and second diaphragms 16 and 17 resonate to emit the first and second sounds having sound pressures equal to or higher than the specified value.

With this structure, the sound output unit 22 (see FIG. 1B) needs to amplify the notification sound signal including at least the first sound signal and the second sound signal to a region where the sound pressure is equal to or higher than the specified value. Therefore, the pronunciation output unit 22 can be miniaturized. As a result, it becomes easy to secure a mounting place for the sound output unit 22, and an increase in the manufacturing cost of the sound output unit 22 can be prevented. Furthermore, the first and second diaphragms 16 and 17 can also be mounted inside the front grille 14, making it easy to secure a mounting location for the approaching vehicle audible system 10. FIG.

In FIG. 3A, the front grille 14 of the vehicle 11 is shown enlarged in the same manner as in FIG. A pair of first and second diaphragms 16 and 17 arranged side by side in the height direction of the vehicle 11 are arranged in the front grille 14 symmetrically with respect to the center line CL.

As shown in FIG. 3(B), the following conditions are stipulated in the sound pressure measurement test according to the Japanese regulations. When the vehicle 11 moves forward, the microphones 31 are installed at a height of 1.2 m from the ground at points 2 m away from the center line CL in the vehicle width direction on both sides of the front end of the vehicle 11, It is measured whether or not the first and second sounds in the frequency band have a sound pressure of 45 dB or more. On the other hand, when the vehicle 11 moves backward, the microphones 31 are installed at a height of 1.2 m from the ground at both sides of the rear end of the vehicle 11 and 2 m apart from the center line CL in the width direction of the vehicle. Measure whether or not the first and second sounds in the two frequency bands have a sound pressure of 45 dB or more.

In particular, in the approaching vehicle notification device 10 (see FIG. 1B) of the present embodiment, when the vehicle 11 moves backward, the first and second diaphragms 16 and 17 attached to the tip of the vehicle 11 generate It is necessary to respond with a notification sound, and in order to satisfy the above test conditions, it is necessary to generate a notification sound with a sound pressure greater than 45 dB.

Therefore, as shown in FIG. 3A, a pair of first and second diaphragms 16 and 17 are arranged in the front grille 14 symmetrically with respect to the center line CL. Then, a notification sound can be transmitted from a pair of the first and second diaphragms 16 and 17 on the near side to the microphone 31 for measurement in the lateral direction of the vehicle 11 .

With this structure, the sound output unit 22 (see FIG. 1B) satisfies the above test conditions without significantly amplifying the notification sound signal including at least the first sound signal and the second sound signal. can. In the approaching vehicle audible system 10, one set of the first and second diaphragms 16 and 17 is added, but the sound output unit 22 does not need to be increased, and can be dealt with by adding a harness. As a result, the size of the sound output unit 22 can be reduced, making it easier to secure a mounting location for the approaching vehicle audible device 10 and preventing an increase in manufacturing costs.

In this embodiment, the case where the first and second diaphragms 16 and 17 are flat plates has been described, but the present invention is not limited to this case. For example, the first and second diaphragms 16 and 17 may be curved so that the front side of the vehicle 11 is convex. In this case, the notification sounds emitted from the first and second diaphragms 16 and 17 are easily transmitted not only to the front side of the vehicle 11 but also to the left and right sides of the vehicle 11 . As a result, the notification sound can be easily transmitted to pedestrians and the like around the vehicle 11, and the pedestrians and the like can easily recognize the approach of the vehicle 11 more reliably.

Moreover, although the case where the first and second diaphragms 16 and 17 are attached to the front grille 14 has been described, the present invention is not limited to this case. For example, the first and second diaphragms 16 and 17 may be attached to the front bumper 13 so as to vibrate. Even in this case, similar effects can be obtained by adjusting the attachment positions of the first and second diaphragms 16 and 17 and the number of sets thereof, as described above. In addition, various modifications are possible without departing from the gist of the present invention.

REFERENCE SIGNS LIST 10 vehicle approach audible device 11 vehicle 13 front bumper 14 front grille 16 first diaphragm 17 second diaphragm 18 emblem 19 vehicle state detector 21 sound control unit 22 sound output unit 23 electric vibration member 31 microphone

Claims (5)

A vehicle approaching notification device that generates a notification sound for notifying surroundings of an approaching vehicle,
a first diaphragm attached to the front part of the vehicle and resonating at a first specific frequency;
a second diaphragm, which is a front part of the vehicle, is attached to the first diaphragm at a distance , and resonates at a second specific frequency that is a lower frequency band than the first specific frequency;
Electric vibration for generating a first sound from the first diaphragm and a second sound from the second diaphragm by vibrating the first diaphragm and the second diaphragm, respectively. comprising a member and
The approaching vehicle audible system is characterized in that, as the notification sounds , the first sound having a predetermined sound pressure or more and the second sound are emitted at the same time . The electric vibrating member repeatedly vibrates the first diaphragm at the first specific frequency to generate the first sound having the predetermined sound pressure or more, and to generate the first sound at the second specific frequency. 2. The approaching vehicle audible system according to claim 1, wherein said second sound having a sound pressure equal to or greater than said predetermined sound pressure is generated by repeatedly vibrating said second diaphragm. 1 or 2, wherein the first diaphragm and the second diaphragm are attached to the front grille of the vehicle at both ends in the longitudinal direction so as to be able to vibrate. 2. The vehicle approach notification device according to 2. The first diaphragm and the second diaphragm are arranged side by side in the height direction of the vehicle,
4. The vehicle according to claim 3, wherein the pair of the first diaphragm and the second diaphragm are mounted symmetrically with respect to a center line of the vehicle in the vehicle width direction. Proximity notification device. 5. The approaching vehicle audible system according to claim 3, wherein said first diaphragm and said second diaphragm are made of a material softer than said front grille.

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