Outdoor-vehicle sound reproduction apparatus and vehicle apparatus

Abstract

Provided is an exterior sound reproduction device that reproduces exterior sound having a further added value while satisfying the requirements specified by the protocol of AVAS. The outside-vehicle sound reproduction apparatus includes a sound reproduction portion that is disposed inside a main body member of a vehicle and emits sound to the outside of the vehicle. The sound reproduction portion includes an exciter, and the exciter is mounted on an inner wall of a main body member of the vehicle. The exciter is mounted at a portion inside a main body member of a vehicle, which is capable of outputting an exterior sound at a sound pressure level satisfying a predetermined requirement at a position having a predetermined distance and a predetermined height from a traveling center line of the vehicle.

Description

Technical Field

[0001] The technology disclosed in this specification (hereinafter referred to as “the present disclosure”) relates to an exterior sound reproducing device and a vehicle device that reproduce exterior sound reaching the periphery of the vehicle in the interior of the vehicle. Background Art

[0002] Since the running sound of electric vehicles is quieter than that of conventional vehicles, as a countermeasure to the problem that pedestrians have difficulty noticing the approach of vehicles, vehicle approach notification devices (Acoustic Vehicle Warning System (AVAS)) have been designed to warn pedestrians, etc. of the approach of vehicles. The United Nations established protocol regulations for AVAS in 2016, and in Japan, it is mandatory to equip applicable vehicles released after March 2018 with AVAS. Protocol regulations R138 on AVAS specify the vehicle speed subject to these regulations, the required sound pressure level, the change in the frequency characteristics of the sound corresponding to the vehicle speed, etc.

[0003] For example, a vehicle approach notification sound control device is proposed, which includes a detection device and a control device for detecting a target object around the vehicle. When the above-mentioned target object has been detected, the control device continuously changes the frequency of the notification sound used to notify vehicles around the vehicle of the approach of the vehicle within a predetermined frequency range, and warns pedestrians, etc. (see PTL 1).

[0004] For example, when an external sound generating device composed of a speaker or the like is installed inside a hood or a bumper, it is difficult to emit the sound outside the vehicle without deteriorating the sound quality. In addition, since the speaker installed outside the vehicle requires a waterproof function, the reproduction frequency band is not very wide, and the sound quality is not satisfactory for audio listening.

[0005] [Citation List]

[0006] [Patent Document]

[0007] [PTL 1]

[0008] JP 2022-11195A

[0009] [PTL 2]

[0010] WO 2021 / 049165

[0011] [PTL 3]

[0012] JP 2005-33593A Summary of the invention

[0013] [Technical issues]

[0014] An object of the present disclosure is to provide an exterior sound reproducing apparatus and a vehicle apparatus which reproduce exterior sound having added value while satisfying the requirements stipulated by the protocol of AVAS.

[0015] [Solution to the problem]

[0016] The present disclosure is proposed in view of the above problems, and a first aspect thereof is an exterior sound reproduction device including a sound reproduction portion, which is disposed inside a body component of a vehicle and radiates sound to the exterior of the vehicle.

[0017] The sound reproducing portion includes an exciter, and the exciter is mounted on the inner wall of the main body of the vehicle. The exciter is mounted on a portion of the inner side of the main body of the vehicle that can output the sound outside the vehicle that meets the predetermined required sound pressure level at a position with a predetermined distance and a predetermined height relative to the driving center line of the vehicle. More specifically, the exciter is mounted on at least one of the inner wall of the front bumper, the air intake duct, and the undercover.

[0018] Alternatively, the sound reproduction portion includes a speaker and a reflection plate installed in front of the speaker and reflecting the radiated sound of the speaker. The sound reproduction portion is arranged in a dead zone in front of the radiator inside the front bumper. The reflection plate reflects the radiated sound of the speaker so as to be concentrated into a narrow passage that can pass through a body part installed in the vehicle, and diffuses after being discharged to the outside of the vehicle through the narrow passage.

[0019] In addition, a second aspect of the present disclosure is a vehicle apparatus including: a main body member; and a sound reproducing portion that is disposed inside the main body member and radiates sound to the outside of a vehicle.

[0020] [Beneficial Effects of the Invention]

[0021] According to the present disclosure, it is possible to provide an exterior sound reproducing apparatus and a vehicle apparatus that reproduce exterior sound having added value while satisfying the requirements stipulated by the protocol of AVAS.

[0022] The effects described in this specification are merely examples, and the effects provided by the present disclosure are not limited thereto. In addition, the present disclosure may have additional effects in addition to the above-described effects.

[0023] Other objects, features, and advantages of the present disclosure will become apparent from the detailed description and accompanying drawings based on the embodiments described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a diagram showing candidate mounting locations of the exciter on the inner wall of the front bumper.

[0025] Figure 21 is a diagram showing corresponding portions of candidate mounting positions on the outer wall of the front bumper.

[0026] Figure 3 : is a graph showing the comparison result of the frequency characteristics when the exciter is installed at each candidate installation position.

[0027] Figure 4 is a graph showing comparison results of sound pressure levels in the case where the exciter is installed at each candidate installation position.

[0028] Figure 5 : is a graph showing the measurement results (100-300 Hz) of the acoustic intensity in the case where the exciter is installed at the first candidate installation position.

[0029] Figure 6 : is a graph showing the measurement results (300-500 Hz) of the acoustic intensity in the case where the exciter is installed at the first candidate installation position.

[0030] Figure 7 : is a graph showing the measurement results (500-700 Hz) of the acoustic intensity in the case where the exciter is installed at the first candidate installation position.

[0031] Figure 8 : is a graph showing the measurement results (700-1000 Hz) of the acoustic intensity in the case where the exciter is installed at the first candidate installation position.

[0032] Fig. 9 : is a graph showing the measurement results (1000 Hz to 3000 Hz) of the acoustic intensity when the exciter is installed at the first candidate installation position.

[0033] Fig.10 It is a diagram showing the measurement results (3000 to 5000 Hz) of the acoustic intensity when the exciter is installed at the first candidate installation position.

[0034] Fig.11 : is a graph showing the measurement results (5000 to 10,000 Hz) of the acoustic intensity in the case where the exciter is installed at the first candidate installation position.

[0035] Fig.12 It is a diagram showing candidate installation positions of the exciter other than the front bumper.

[0036] Fig.13 The figure shows a cross section of a front bumper on which a plurality of exciters are mounted so as to be aligned in the horizontal direction.

[0037] Fig.14 14 is a diagram showing a functional configuration of an exterior-vehicle sound reproducing apparatus 1400 (first embodiment) combined with an in-vehicle sensor.

[0038] Fig.15 : is a diagram showing a view (a view viewed from the front side of the vehicle) in which the exterior sound reproducing apparatus (second embodiment) is arranged in the front bumper.

[0039] Fig.16 : is a diagram showing a view in which the exterior sound reproducing apparatus (second embodiment) is arranged in the front bumper.

[0040] Fig.17 It is an enlarged view of the exterior sound reproducing device (second embodiment) in the front bumper.

[0041] Fig.18 It is a diagram showing the front configuration of the speaker 1701.

[0042] Fig.19 1702 is a diagram showing the shape of the reflecting surface of the reflecting plate 1702.

[0043] Fig. 20 1802 is a diagram showing simulation results based on sound ray analysis of sound rays emitted from tweeter 1802 .

[0044] Fig.21 1802 is a diagram showing simulation results based on sound ray analysis of sound rays emitted from tweeter 1802 .

[0045] Fig. 22 This is a diagram showing the simulation results of the sound ray analysis of the sound rays emitted from the tweeter 1802 from the top surface.

[0046] Fig.23 This is a diagram showing the simulation result based on the sound ray analysis of the sound rays emitted from the tweeter 1802 from the side.

[0047] Fig.24 18 is a diagram showing simulation results based on sound ray analysis of sound rays emitted from the low frequency speaker 1801 .

[0048] Fig.25 18 is a diagram showing simulation results based on sound ray analysis of sound rays emitted from the low frequency speaker 1801 .

[0049] Fig.26 This is a diagram showing the simulation results of the sound ray analysis of the sound rays emitted from the low frequency speaker 1801 from the top surface.

[0050] Fig. 27 18 is a diagram showing a simulation result based on a sound ray analysis of sound rays emitted from the low frequency speaker 1801 from a side view.

[0051] Fig.28 It is a diagram showing the simulation result (first resonance mode) of the vibration of the reflection plate.

[0052] Fig.29 It is a diagram showing the simulation result (second resonance mode) of the vibration of the reflection plate.

[0053] Fig.30 is a diagram showing the measurement results of the sound pressure level of the sound output from the exterior sound reproducing apparatus (second embodiment).

[0054] Fig.31 is a diagram showing the measurement results of the intensity of the radiated sound radiated from the exterior sound reproducing apparatus (second embodiment) of the vehicle.

[0055] Fig.32 is a diagram showing the measurement results of the intensity of the radiated sound radiated from the exterior sound reproducing apparatus (second embodiment) of the vehicle.

[0056] Fig.33 : is a diagram showing the measurement results (vehicle left front side) of the sound pressure level of the radiated sound radiated from the exterior sound reproducing apparatus (second embodiment).

[0057] Fig.34 : is a diagram showing the measurement results (vehicle right front side) of the sound pressure level of the radiated sound radiated from the vehicle exterior sound reproducing apparatus (second embodiment).

[0058] Fig.35 : is a diagram showing the measurement results (rear left side of the vehicle) of the sound pressure level of the radiated sound radiated from the exterior sound reproducing apparatus (second embodiment).

[0059] Fig.36 : is a diagram showing the measurement results (right rear side of the vehicle) of the sound pressure level of the radiated sound radiated from the exterior sound reproducing device (second embodiment).

[0060] Fig.37 37 is a diagram showing a functional configuration of an exterior-vehicle sound reproducing apparatus 3700 (second embodiment).

[0061] Fig.38 38 is a diagram showing a functional configuration of an exterior-vehicle sound reproducing apparatus 3800 (second embodiment).

[0062] Fig.39 It is a diagram (perspective view) showing the external configuration of the actuator.

[0063] Fig.40 are diagrams (top view and side view) of the external configuration of the actuator.

[0064] Fig.41 : is a diagram showing a method of installing the exciter in the front bumper (a view in which a pedestal is fixed to the inner wall of the front bumper).

[0065] Fig.42is a diagram showing a method of installing the exciter in the front bumper (a view in which the exciter is fixed to the inner wall of the front bumper via a mount). DETAILED DESCRIPTION

[0066] Hereinafter, the present disclosure will be described in the following order with reference to the drawings.

[0067] A. Overview

[0068] B. First Embodiment

[0069] B-1. Arrangement of exciters in the front bumper

[0070] B-2. Comparison of frequency characteristics at various candidate installation positions

[0071] B-3. ​​Other candidate installation locations

[0072] B-4. Application to other purposes

[0073] B-5. How to install the actuator

[0074] C. Second Embodiment

[0075] C-1. Configuration Example

[0076] C-2. Simulation results

[0077] C-2-1. Simulation results of acoustic rays

[0078] C-2-2. Simulation results of reflector

[0079] C-3. Measurement results

[0080] C-4. Functional Configuration

[0081] C-4-1. First configuration example

[0082] C-4-2. Second configuration example

[0083] A. Overview

[0084] AVAS is a vehicle approach notification device used to notify pedestrians, etc. of the approach of a vehicle in consideration of the quietness of the running sound of an electric vehicle. In R138 "Agreement Provisions on Quiet Vehicles", for example, the following requirements for AVAS are stipulated.

[0085] (1) Vehicle speed limit

[0086] Forward driving and reverse driving at 10km / h and 20km / h are restricted. However, there is no obligation to make a sound when stopped (0km / hr), and there is no obligation to make a sound at a vehicle speed exceeding 20km / h.

[0087] (2) Sound pressure

[0088] When traveling at the above-mentioned restricted target speed, the A-weighted sound pressure level is measured using a microphone installed 2.0m laterally on the center line of the vehicle and 1.2m above the ground, and frequency analysis is performed, requiring the measured sound pressure level to exceed the total level and the level set for each 1 / 3 octave band. For the 1 / 3 octave band, the measured pressure level is required to exceed the level set in at least two bands, and at least one of the bands is required to be a band with a center frequency of 1.6kHz or less. A-weighting is a frequency weighting characteristic that takes into account the sensitivity of human hearing, which is used for measurement using a noise meter and is specified in JIS C 1502-1990.

[0089] It is specified in the "General Sound Level Meter".

[0090] (3) Acceleration and deceleration

[0091] The sound from the AVAS needs to change its frequency characteristics according to the speed. More specifically, it is required that at least one component sound in the generated sound shifts by 0.8% per 1 km / h on average within the speed range of 5 to 20 km / h.

[0092] (4) Others

[0093] The temporary stop function of the AVAS sound is prohibited. For example, even if the driver determines that the sound is not necessary in a residential area late at night, on a crowded highway, etc., the sound emission cannot be temporarily stopped. On the other hand, as long as the above requirements are met, the function of selecting the tone and sound pressure is allowed.

[0094] The present disclosure proposes an exterior sound reproduction device that meets the above requirements and can reproduce high value-added exterior sound with high sound quality sufficient for audio listening. In addition, the exterior sound reproduction device according to the present disclosure can be applied not only to the reproduction of vehicle approach notification sound, but also to the output of various exterior sounds such as answering sound, etc.

[0095] B. First Embodiment

[0096] In this section B, as a first embodiment of the present disclosure, an exterior sound reproducing apparatus constituted by an exciter mounted inside a body member of a vehicle and using a portion near the mounting position of the body member as a vibration plate will be described.

[0097] The exciter is a vibration plate driving unit that drives a vibration plate and converts the electrical signal into sound by driving the vibration plate with an input electrical signal. A general conduction-type exciter includes: a voice coil to which an electrical signal is input; and a magnetic circuit formed by a permanent magnet and a yoke that generates a magnetic field around the voice coil. Typically, the exciter is installed in a speaker box for outdoor or home music listening, or is installed in the cabin of a vehicle and is used for the audio reproduction of music or voice output from a radio or car stereo. For example, a car speaker system using an exciter has been proposed (see PTL 2). In the present embodiment, the exciter is applied not to the audio reproduction in the cabin but to the reproduction of external sounds such as warning sounds of AVAS.

[0098] B-1. Arrangement of exciters in the front bumper

[0099] Considering that the A-weighted sound pressure level measured by a microphone installed at 2.0 m lateral to the vehicle's driving centerline and at a height of 1.2 m above the ground meets the requirements specified in the R138 protocol (as described above), the exterior sound reproduction device according to this embodiment is configured to reproduce exterior sound by installing an exciter on the inner wall of the front bumper and using the portion where the front bumper is installed as a vibration plate.

[0100] exist Figure 1 , three positions 101 to 103 are shown as candidate installation positions of the exciter on the inner wall of the front bumper. Figure 2 , portions corresponding to candidate installation positions 101 to 103 are shown on the outer wall of the front bumper. Since the A-weighted sound pressure level measured by a microphone installed at 2.0 m on the lateral side of the vehicle's driving centerline and at a height of 1.2 m above the ground meets the requirement, all candidate installation positions 101 to 103 are arranged near the left and right ends of the front bumper. More specifically, the first candidate installation position 101 is arranged at a portion close to the left and right sides, which are located slightly outside the curved portion of the front bumper. In addition, the second candidate installation position 102 is arranged at a portion close to the left and right curved portions on the front face of the front bumper, and the third candidate installation position 103 is arranged at a portion close to the slightly center side on the front face of the front bumper.

[0101] exist Figure 1 , a view showing an arrangement of an exciter at a portion of each candidate mounting position 101 to 103 on the inner wall of the front bumper is shown. The exciter has a cylindrical outer shape, has an acoustic output unit configured using a coil, a yoke, a magnet, etc. arranged inside, and reproduces exterior sound diffused toward the outside of the vehicle by vibrating a portion near the mounting position of the front bumper by vibrating in the axial direction.

[0102] B-2. Comparison of frequency characteristics at various candidate installation positions

[0103] exist Figure 3 In the figure, it is shown that Figure 1 and Figure 2 Frequency characteristics measured when the exciter is installed at each of the candidate installation positions 101 to 103 are shown. Here, the horizontal axis represents the frequency axis (Hz) and the vertical axis represents the sound pressure level (dB). The measurement result of the case where the exciter is installed at the first candidate installation position 101 is represented by a black solid line, the measurement result of the case where the exciter is installed at the second candidate installation position 102 is represented by a black thin dotted line, and the measurement result of the case where the exciter is installed at the third candidate installation position 103 is represented by a gray solid line.

[0104] There is no large difference in frequency characteristics between the candidate installation position 101 and the candidate installation position 103. Since the first candidate installation position 101 is arranged at portions close to the left and right sides of the outer side of the curved portion of the front bumper, sound is easily propagated to the side. On the other hand, since the third candidate installation position 103 is arranged at a portion close to the slightly central side of the front surface of the front bumper, sound is easily output to the front side.

[0105] exist Figure 4 , there are shown comparison results of sound pressure levels in the case where the exciter is installed at each of the candidate installation positions 101 to 103. At the first candidate installation position 101 and the third candidate installation position 103, which are relatively flat portions of the front bumper, a high sound pressure level can be obtained. In contrast, at the second candidate installation position 102, which is close to the curved portion of the front bumper, the sound pressure level becomes low.

[0106] When reviewing Figure 3 and 4 When comparing the frequency characteristics and the sound pressure levels shown, it is concluded that the first candidate installation position 101 is more suitable as the installation position of the exciter. In the case where the exciter is installed at the first candidate installation position 101 of the front bumper, by using this position of the front bumper as a vibration plate, it is possible to widely transmit sound with a higher sound pressure level to the side of the vehicle. Hereinafter, the installation of the exciter at the first candidate installation position 101 having horizontal symmetry on the inner wall of the front bumper will be described.

[0107] Figures 5 to 11 The measurement results of the sound intensity of each frequency band obtained in the case where the exciter is installed at the first candidate installation position 101 are shown. Figure 5 , 6 , 7, 8, 9, 10, 11 are 100-300Hz, 300-500Hz, 500-700Hz, 700-1000Hz,

[0108] The sound intensity measurement results in each frequency band of 1000-3000Hz, 3000-5000Hz, and 5000-10000Hz. Figures 5 to 11 It can be understood that when the exciter installed at the first candidate installation position 101 vibrates these positions of the front bumper, in the measurement specified by the R138 protocol in each frequency band, sound with a sound pressure level that meets the requirements specified in the protocol of AVAS is radiated near the microphone position (2.0m to the lateral side from the vehicle's driving centerline and at a height of 1.2m above the ground).

[0109] The vehicle exterior sound reproducing device configured by mounting the exciter at the first candidate mounting position 101 of the front bumper has sufficient acoustic strength in each frequency band, and therefore it is considered that various sounds can be reproduced.

[0110] B-3. ​​Other candidate installation locations

[0111] In the above-mentioned sections B-1 and B-2, an off-vehicle sound reproducing apparatus having a configuration in which an exciter is installed in the front bumper is described. In addition, although the exciter is directly installed in a body member of the vehicle other than the front bumper, similarly, a sound having high sound quality that satisfies the requirements of high sound pressure level and frequency characteristics can be reproduced at a position specified in the R138 protocol provisions (2.0 m to the lateral side from the vehicle running center line and 1.2 m above the ground).

[0112] Fig.12 The figure shows candidate installation positions of the exciter on the front side of the vehicle other than the front bumper. In the figure, reference numeral 1201 indicates a candidate installation position set in the intake duct, and reference numerals 1202 and 1203 indicate candidate installation positions set in the undercover. Obviously, even if the exciter is installed in a position other than the front bumper and Fig.12 The exterior sound reproducing device according to this embodiment can also be arranged in the main body member of each part that can function as a vibration plate on the front side, side side, rear side, ceiling and bottom surface of the vehicle other than the positions shown.

[0113] B-4. Application to other purposes

[0114] By directly installing the exciter in the main body part of the vehicle (such as the front bumper, etc.) and using the main body part as a vibration plate, the vehicle exterior sound reproduction device according to the present embodiment fully satisfies the sound pressure and characteristics at the position specified in the R138 protocol provisions, as described in the above-mentioned section B-2. According to the configuration in which the exciter is directly installed and the main body part is used as a vibration plate, a sound with high sound quality can be generated, and thus the sound quality of the notification sound of the AVAS can be improved, and in addition, an icon sound (which is distinctive and allows easy understanding of the content to be delivered) can be reproduced.

[0115] The use of the vehicle exterior sound reproduction device according to the present embodiment is not limited to the output of the notification sound of the AVAS. The vehicle exterior sound reproduction device according to the present embodiment is not limited to the target vehicle speed, and in particular, is not limited to the target vehicle speed specified by the R138 protocol. For example, when driving at a low speed or a high speed that is not a specified target, it can also be used to reproduce the vehicle exterior sound for a new warning to the surrounding pedestrians. In addition, the vehicle exterior sound reproduction device according to the present embodiment can also be used for the response sound.

[0116] By installing two or more exciters in the main body part of the vehicle to achieve stereo sound, they can be used for the reproduction of the notification sound of AVAS and other sound reproduction. In parts B-1 and B-2, the vicinity of the side surface located slightly outside the curved part of the front bumper is described as the optimal exciter installation position. In addition, by installing the exciter at two or more places including these installation positions of the front bumper (or the main body part of the vehicle other than the front bumper) to achieve stereo sound, the notification sound and the answering sound of AVAS can be reproduced with a wide range of sound effects.

[0117] Fig.13 1 is a diagram showing an example of a cross-sectional view of a front bumper 1300 on which a plurality of exciters 1301, 1302, ... are mounted in a horizontal direction. Since the mounting portion of the exciters 1301, 1302, ... operates as a vibration plate, the front bumper 1300 functions as a line array speaker in which a plurality of speaker units are arranged in a horizontal direction. Therefore, the vehicle exterior sound reproduction device formed by the front bumper 1300 on which the plurality of exciters 1301, 1302, ... are mounted improves the sound pressure level of the reproduced sound and is capable of transmitting a clear and uniform sound source in a desired direction through beam steering.

[0118] As described in the above-mentioned section B-2, the vehicle exterior sound reproduction device according to the present embodiment has sufficient acoustic intensity in each frequency band, and thus can reproduce high-quality sounds in various ranges. Therefore, in addition to the output of the notification sound of the AVAS, the vehicle exterior sound reproduction device according to the present embodiment can also reproduce sounds with different tones and different melodies according to various purposes such as answering, etc. For example, the tone or melody of the vehicle approach notification sound can be switched between the case where the vehicle is moving forward and the case where the vehicle is moving backward. In addition, for the application of the answering function, for example, when the door is locked and when the door is unlocked, the tone or melody of the reproduced sound can be finely switched. In this case, the listener can recognize whether the vehicle exterior sound that is now being emitted indicates one of the notification and answer (door locked or unlocked) of the vehicle approaching.

[0119] For example, in combination with an in-vehicle sensor installed in a vehicle, the exterior sound reproducing apparatus according to the present embodiment can be used for a plurality of purposes at the same time. Fig.14 The functional configuration of the exterior-vehicle sound reproducing apparatus 1400 combined with the vehicle-mounted sensor is schematically shown.

[0120] The illustrated exterior-vehicle sound reproducing device 1400 includes an exciter 1402 , a detection section 1403 , an identification section 1404 , and a drive control section 1405 .

[0121] The exciter 1402 is directly mounted in the body part 1401 of the vehicle. Although the body part 1401 of the vehicle is representatively a front bumper, it may be any other body part of the vehicle, such as an air intake duct, an undercover, a rear bumper, etc. In addition, at least one exciter 1402 is mounted in the body part 1401, and as described above, it is more preferably in the form of a stereo speaker, a line speaker array, etc., in which two or more exciters are mounted in the body part 1401.

[0122] The detection section 1403 is formed of vehicle-mounted sensors, etc. The vehicle-mounted sensors include an external recognition sensor, a vehicle interior sensor, and a vehicle sensor. The detection section 1403 may use some vehicle-mounted sensors equipped in a vehicle control system.

[0123] The external recognition sensor is formed of one or more sensors for recognizing the external situation of the vehicle (nearby pedestrians, front vehicles, rear vehicles, etc.), and includes cameras, radars, light detection and ranging (laser imaging detection and ranging (LiDAR)), ultrasonic sensors, etc. In addition, the external recognition sensor may also include an environmental sensor (rain sensor, fog sensor, sunlight sensor, snow sensor, illumination sensor, etc.) for detecting the surrounding environment of the vehicle and a microphone for receiving the surrounding sound of the vehicle.

[0124] The vehicle interior sensor is a camera, radar, seat occupancy sensor, steering wheel sensor, microphone, biometric sensor, etc. installed to detect the interior of the vehicle as a detection range. The vehicle sensor is formed of one or more sensors that detect the state of the vehicle. In the case where it is not necessary to sense the interior condition of the vehicle for the control of the reproduction of the sound outside the vehicle, the vehicle interior sensor is unnecessary.

[0125] Vehicle sensors may include speed sensors, acceleration sensors, angular velocity sensors (gyro sensors) or inertial measurement units (IMUs) that integrate these sensors, steering angle sensors that detect the steering angle of the steering wheel, yaw rate sensors, accelerator sensors that detect the operation amount of the accelerator pedal, brake sensors that detect the operation amount of the brake pedal, rotation sensors that detect the speed of the engine or motor, tire pressure sensors that detect the air pressure of the tires, slip sensors that detect the slip rate of the tires, wheel speed sensors that detect the speed of the wheels, battery sensors that detect the remaining battery capacity and temperature, impact sensors that detect impacts from the outside, and the like.

[0126] The recognition section 1404 recognizes an event occurring in the vehicle based on the detection signal acquired by the detection section 1403. The recognition section 1404 may perform recognition processing using, for example, a machine learning model learned to estimate an event on the vehicle based on the detection signal by deep learning.

[0127] The events occurring in the vehicle are various. However, in the present embodiment, it is assumed that the recognition section 1404 recognizes at least an event for which an external sound needs to be output. More specifically, the events for which an external sound needs to be output include the occurrence of an event for which an AVAS notification sound needs to be generated, such as the occurrence of an event for which an AVAS notification sound needs to be generated, such as the occurrence of an event in which the vehicle reaches a prescribed object speed specified by the R138 protocol, the occurrence of an event in which a warning sound other than AVAS needs to be generated regardless of the vehicle speed according to the approach of a pedestrian, the occurrence of an event such as locking or opening a door for which a notification response is required, and the like.

[0128] The drive control section 1405 controls the drive of the actuator 1402 to generate an external vehicle sound formed of a volume, a pitch, a melody, a heading direction, etc. suitable for the event recognized by the recognition section 1404.

[0129] As described above, the sound source of the exterior sound reproduction device 1400 is the exciter 1402 directly installed in the main body part 1401 of the vehicle, but it is capable of reproducing a wide variety of high-quality sounds. Therefore, in addition to outputting the notification sound of the AVAS, the exterior sound reproduction device 1400 can also reproduce sounds with different tones and melodies according to various uses such as answering, etc. For example, the tone or melody of the vehicle approach notification sound can be switched between the case where the vehicle is moving forward and the case where the vehicle is moving backward. In addition, in the application of the answering function, for example, the tone or melody of the reproduced sound can be finely switched between when locking the door and when unlocking the door.

[0130] B-5. How to install the actuator

[0131] The vehicle exterior sound reproduction device according to the present embodiment is configured to install an exciter on the inner side of a vehicle main body component such as the inner wall of a front bumper, and use a portion of the main body component near the installation position as a vibration plate. In order to efficiently transmit the vibrations of the exciter without any loss, they need to be installed in the main body component. Generally, the inner wall of the front bumper is formed as a curved surface. Therefore, in the present embodiment, a mounting method is used, in which, after a flat structure is formed on the inner wall of the front bumper near the installation position of the exciter, the exciter is fixed to the flat surface. Obviously, any other mounting method can be used as long as the exciter can be installed so that the vibrations of the exciter can be efficiently transmitted without any loss.

[0132] Fig.39 and 40 The external configuration of the actuator is shown. Fig.39 is a perspective view of the actuator 3900 viewed from above, Fig.40 There are shown a top view and a side view of the exciter 3900. The illustrated exciter 3900 includes a main body portion 3901 that generates vibrations that form the basis for reproducing sound, and a frame portion 3902 that protrudes outward from the bottom of the main body portion 3901.

[0133] The main body 3901 is formed in a cylindrical shape. Inside the main body 3901, a voice coil into which an electrical signal is input and a magnetic circuit formed by a permanent magnet and a yoke are installed, which generates a magnetic field around the voice coil and generates vibration in the axial direction of the cylinder according to the input electrical signal.

[0134] The frame portion 3902 is a flange-shaped protrusion protruding from the vicinity of the bottom surface of the main body portion 3901, and is formed in a rectangular flat plate shape. A wire 3903 for inputting an electrical signal is connected to one side of the flange portion 3902. At the four corners of the frame portion 3902, screw holes for inserting and passing fixing screws (m4 screws) are formed.

[0135] The vibration generated by the main body portion 3901 is output to the outside through the frame portion 3902. For this purpose, the flat frame portion 3902 must be installed in close contact with the main body member serving as a vibration plate. Fig.41 and Fig.42 A method of mounting the actuator 3900 on the inner wall of the front bumper is described.

[0136] The inner wall of the front bumper is formed as a curved surface. Therefore, a flat structure serving as a mounting surface of the exciter 3900 is formed on the inner wall of the front bumper near the mounting position of the exciter. More specifically, Fig.41 As shown, a pedestal 4100 whose top surface is a plane shape corresponding to the mounting surface of the exciter 3900 and whose bottom surface is a shape that matches the inner wall of the front bumper is fixed on the inner wall of the front bumper. The pedestal 4100 can be manufactured using a 3D printer based on the 3D shape data of the inner wall of the front bumper. Obviously, the pedestal can be manufactured using a processing method other than the method using a 3D printer. Then, the manufactured pedestal 4100 is bonded to an appropriate position on the inner wall of the front bumper using panel bonding or the like.

[0137] In addition, if Fig.42 As shown, the exciter 3900 is mounted on the flat mounting surface of the pedestal 4100 on the inner wall of the front bumper. The exciter 3900 can be fixed to the inner wall of the front bumper by fastening the four corners of the frame portion 3902 to the mounting surface with screws. Thereafter, the exciter 3900 can reproduce the vehicle exterior sound radiated to the outside of the vehicle by vibrating the front bumper as a vibration plate. However, in the case where the flat surface corresponding to the mounting surface of the exciter 3900 is formed in a shape integral with the inner wall of the front bumper, the pedestal 4100 becomes unnecessary.

[0138] C. Second Embodiment

[0139] In this section C, as a second embodiment of the present disclosure, an exterior sound reproduction device will be described, which includes a speaker for reproducing exterior sound, the speaker being placed in the front bumper of the vehicle, and a path changing unit that changes the path so that the sound from the speaker is released to the outside of the vehicle. More specifically, the path changing unit is formed by a reflection plate that reflects sound. The reflection plate has an appropriate shape for reflecting the sound from the speaker so that the sound converges to pass through a narrow passage such as an air intake, and then diffuses after being released to the outside of the vehicle through the narrow passage.

[0140] The speaker for reproducing the notification sound of AVAS is installed outside the vehicle cabin, so a waterproof function is required. Conventional speakers for reproducing notification sounds are configured only for warning purposes, so the reproduction range is 100 to 5000 Hz, which is not so wide, and the sound quality is not so good. In contrast, the off-vehicle sound reproduction device according to the present embodiment is configured so that a waterproof speaker unit is placed using the dead space in front of the radiator of the vehicle, and a reflective plate of an appropriate shape is used to emit high-quality sound suitable for audio listening in a wide range of 50 to 20000 Hz to the outside of the vehicle via a narrow channel.

[0141] C-1. Configuration Example

[0142] Fig.15 and 16 A view showing that the exterior sound reproducing device according to the embodiment is disposed in a dead space in front of a radiator in a front bumper. Fig.15 A diagram showing the exterior sound reproducing device 1500 viewed from the front of the vehicle (outside the vehicle) is shown. Actually, since the exterior sound reproducing device 1500 is disposed on the rear side near the license plate, it is difficult to view it from the front side of the vehicle. Fig.16 16 shows a view of the exterior sound reproducing apparatus 1600 viewed from the inside of the front bumper. Fig.17 An exterior sound reproducing device disposed near the rear side of the license plate inside the front bumper is shown on an enlarged scale.

[0143] Radar equipment, etc. (not shown) is placed in front of the vehicle, and when the speaker is installed to face forward, the sound from the speaker is trapped in the front bumper, so it becomes difficult to meet the requirements of the sound pressure level at the position specified in the R138 agreement regulations (2.0m to the lateral side from the vehicle's running center line and 1.2m above the ground). Fig.16 and 17 As shown, the vehicle exterior sound reproducing device 1700 (or 1600) has a configuration in which the directivity of the sound can be controlled by placing a speaker 1701 facing the rear side (i.e., directing the radiation direction of the sound to the rear side) and placing the front side (radiation direction of the sound) of the speaker 1701 on a reflection plate 1702. The reflection plate 1702 has an appropriate shape for reflecting the sound from the speaker so that the sound is converged to be able to pass through a narrow passage such as an air intake and then diffused after being discharged to the outside of the vehicle through the narrow passage.

[0144] Fig.18The front configuration of the speaker 1701 is shown. The speaker 1701 is an axial (coaxial) speaker device, in which a plurality of speakers covering mutually different sound frequency ranges are coaxially arranged, and a high-frequency speaker (tweeter) 1802 is installed on the front side of the center pole of the low-frequency speaker (woofer) 1801. This speaker device can perform high-quality reproduction in a wide frequency range from a low-frequency band to a high-frequency band, and can radiate the sound covering each frequency band emitted from the speaker from the approximate center of the low-frequency speaker. This coaxial speaker device can be configured to be compact as a whole, and is therefore widely used as a vehicle-mounted speaker device (for example, see PTL 3). In addition, considering that the speaker 1701 is installed outside the vehicle, it is preferred that the speaker is a waterproof speaker unit with a waterproof function.

[0145] Fig.19 The external appearance of a reflection plate 1702 disposed in front of a speaker 1701 is shown. Fig.19 The surface shape of the reflection plate 1702 is shown, that is, from the speaker 1701 side (that is, with Fig.16 and Fig.17 The reflective plate 1702 is a reflective surface that reflects the sound radiated from the speaker 1701 when viewed from the opposite side of the example shown. The reflective plate 1702 controls the directivity by reflecting the radiated sound from the speaker 1701 so that it is temporarily concentrated to be able to pass through a narrow passage such as an air intake, etc., and diffused after being discharged to the outside of the vehicle through the narrow passage.

[0146] Corresponding to the speaker 1701 configured by the woofer 1801 and the tweeter 1802 in a coaxial form, the reflection plate 1702 includes a reflection surface that reflects the radiated sound from the woofer 1801 and a reflection surface that reflects the radiated sound from the tweeter 1802 .

[0147] The reflecting plate 1702 has a first reflecting portion 1901 , a second reflecting portion 1902 , a third reflecting portion 1903 , a fourth reflecting portion 1904 , a fifth reflecting portion 1905 , and a sixth reflecting portion 1906 which are reflecting surfaces for the tweeter 1802 .

[0148] The first reflecting portion 1901 and the second reflecting portion 1902 have a horizontally symmetrical concave reflecting surface. The first reflecting portion 1901 and the second reflecting portion 1902 reflect the high-frequency sound waves received directly from the tweeter 1802, and generate parallel waves directed to the fifth reflecting portion 1905 and the sixth reflecting portion 1906, respectively. The concave surface described here is realized by an appropriate parabolic surface, so that the sound lines diverging from the center of the sound source of the tweeter 1802 converge into parallel waves by reflection. The fifth reflecting portion 1905 and the sixth reflecting portion 1906 have a horizontally symmetrical convex reflecting surface, and further reflect the parallel waves received from the first reflecting portion 1901 and the second reflecting portion 1902 to the narrow channel side (the air intake on the left and right sides) connected to the outside of the vehicle, and generate a diffuse wave that spreads after being discharged to the outside of the vehicle through the narrow channel in two stages. By reflecting the sound lines in two stages in this way, the reflecting surface can be configured to be smaller.

[0149] The third reflecting portion 1903 and the fourth reflecting portion 1904 have a horizontally symmetrical concave reflecting surface. The concave surface described here is realized by an appropriate parabolic surface to which an appropriate opening ratio is applied so that the sound rays diverging from the center of the sound source of the high-frequency speaker 1802 are directly reflected to the narrow channel side (the air intakes on the left and right sides), and can diffuse to the outside of the vehicle after passing through the narrow channel. The third reflecting portion 1903 and the fourth reflecting portion 1904 reflect the high-frequency sound waves directly received from the high-frequency speaker 1802 to the narrow channel side (the air intakes on the left and right sides) connected to the outside of the vehicle, and generate diffuse waves in one stage that diffuse after being discharged to the outside of the vehicle through the narrow channel.

[0150] In addition, the reflecting plate 1702 has a seventh reflecting portion 1907, an eighth reflecting portion 1908, a ninth reflecting portion 1909, and a tenth reflecting portion 1910 as reflecting surfaces for the low frequency speaker 1801. The seventh reflecting portion 1907, the eighth reflecting portion 1908, the ninth reflecting portion 1909, and the tenth reflecting portion 1910 all have reflecting surfaces in a concave shape, and are respectively arranged outside the first reflecting portion 1901, the third reflecting portion 1903, the second reflecting portion 1902, and the fourth reflecting portion 1904. The concave surface described here is realized by an appropriate parabolic surface to which an appropriate opening ratio is applied, so that the sound rays diverging from the sound source center of the low frequency speaker 1801 are reflected to the narrow channel side (the air intakes on the left and right sides), and can be diffused to the outside of the vehicle after passing through the narrow channel. Therefore, the seventh reflecting portion 1907, the eighth reflecting portion 1908, the ninth reflecting portion 1909, and the tenth reflecting portion 1910 reflect the low-frequency sound waves directly received from the low-frequency speaker 1801 to the narrow passage side (the air intakes on the left and right sides) connected to the outside of the vehicle, and generate a diffuse wave that diffuses after being discharged to the outside of the vehicle through the narrow passage in one stage. The fifth reflecting portion 1905 and the sixth reflecting portion 1906 used in the second-stage reflection of the sound waves of the high-frequency sound waves are respectively arranged on the outer sides of the eighth reflecting portion 1908 and the tenth reflecting portion 1910.

[0151] The purpose of the reflective plate 1702 is to control directivity so that the sound waves from the low-frequency speaker 1801 and the high-frequency speaker 1802 pass through a narrow passage (the air intake ports on the left and right sides) and are converted into diffuse waves that are discharged toward the front side of the vehicle. By introducing a structure that reflects sound waves in two stages, etc., the reflection surface is set smaller and the reflective plate 1702 can be formed compact. Therefore, air can be efficiently sent to the radiator (not shown) on the rear side without the reflective plate 1702 interfering with the air flowing from the air intake ports into the interior of the vehicle. Fig.19 The shape of the reflection plate 1702 shown is an example, and other shapes are possible as long as the directivity control of the radiated sound from the speaker 1701 can be similarly achieved.

[0152] There is a risk that stones on the road surface and the like enter the inside of the front bumper. In addition, the vehicle exterior sound reproduction device according to the present embodiment has a structure in which the sound from the speaker 1701 is reflected by the reflector 1702 and radiated to the outside of the vehicle. When the reflector 1702 is deformed due to acoustic resonance, the reflection direction deviates from the narrow passage (air inlet), and the reflected sound cannot be radiated to the outside of the vehicle, thereby deteriorating the sound pressure and sound quality. Therefore, the vehicle exterior sound reproduction device according to the present embodiment needs to have sufficiently high mechanical strength, and needs to suppress acoustic resonance. The details of this point will be described below (C-2-2 section shown below). In addition, by using reflected sound, a configuration in which the speaker 1701 is arranged to face the rear side is adopted, and therefore the risk of the speaker 1701 being damaged due to direct impact by stones and the like entering the inside of the front bumper can be significantly reduced.

[0153] C-2. Simulation results

[0154] In this Section C-2, the performance of the exterior sound reproducing apparatus according to the embodiment described in the above Section C-1 will be examined based on simulation.

[0155] C-2-1. Acoustic simulation results

[0156] First, in Section C-2-1, a simulation result of a sound ray emitted from each of the tweeter 1802 and the woofer 1801 in the vehicle exterior sound reproducing device in which the speaker 1701 and the reflecting plate 1702 have Fig.18 and 19 Configuration shown.

[0157] Figures 20 to 23 The simulation result of the sound ray analysis based on the sound ray emitted from the tweeter 1802 is shown. In the figure, a plurality of sound rays emitted from the tweeter 1802 obtained by the sound ray simulation and the traveling direction of the sound ray after being reflected by the reflection plate 1702 are depicted. Here, Fig. 20 A view showing, on an enlarged scale, that sound rays emitted from the tweeter 1802 are reflected by the reflection portions 1901 to 1906 of the reflection plate 1702 . Figures 21 to 23 The behavior of the sound rays emitted from the tweeter 1802 on the inner side of the front bumper is shown. Fig.21 17 shows a perspective view of the reflective plate 1702 viewed from the front side, Fig. 22 17 shows a view of the reflective plate 1702 viewed from the upper side, Fig.23 A view of the reflective plate 1702 from a lateral side is shown.

[0158] from Figures 20 to 23It can be understood that the first reflection portion 1901 and the second reflection portion 1902 reflect the high-frequency sound waves directly received from the tweeter 1802, and generate parallel waves directed to the fifth reflection portion 1905 and the sixth reflection portion 1906. The fifth reflection portion 1905 and the sixth reflection portion 1906 have horizontally symmetrical convex reflection surfaces, further reflecting the parallel waves arriving from the first reflection portion 1901 and the second reflection portion 1902 to the narrow channel side connected to the outside of the vehicle (the air intakes on the left and right sides), and generating diffuse waves that diffuse after being discharged to the outside of the vehicle through the narrow channel in two stages. In addition, the third reflection portion 1903 and the fourth reflection portion 1904 reflect the high-frequency sound waves directly received from the tweeter 1802 to the narrow channel side connected to the outside of the vehicle (the air intakes on the left and right sides), and generate diffuse waves that diffuse after being discharged to the outside of the vehicle through the narrow channel in one stage.

[0159] Figures 24 to 27 The simulation result of the sound ray analysis based on the sound ray emitted from the low frequency speaker 1801 is shown. In the figure, a plurality of sound rays emitted from the low frequency speaker 1801 obtained by the sound ray simulation and the traveling direction of the sound rays after being reflected by the reflection plate 1702 are plotted. Here, Fig.24 A view showing, on an enlarged scale, that sound rays emitted from the tweeter 1802 are reflected by the reflection portions 1901 to 1906 of the reflection plate 1702 . Figures 25 to 27 The behavior of the sound rays emitted from the tweeter 1802 on the inner side of the front bumper is shown. Fig.25 17 shows a perspective view of the reflective plate 1702 viewed from the front side, Fig.26 17 shows a view of the reflective plate 1702 viewed from the upper side, Fig. 27 A view of the reflective plate 1702 from a lateral side is shown.

[0160] from Figures 24 to 27 It can be understood that the seventh reflection portion 1907, the eighth reflection portion 1908, the ninth reflection portion 1909 and the tenth reflection portion 1910 reflect the low-frequency sound waves directly received from the low-frequency speaker 1801 to the narrow channel side connected to the outside of the vehicle (the air intakes on the left and right sides), and generate a diffusion wave in one stage that diffuses after being discharged to the outside of the vehicle through the narrow channel.

[0161] C-2-2. Simulation results of reflector

[0162] There is a risk that stones on the road surface etc. enter the inside of the front bumper. In addition, the vehicle exterior sound reproduction device according to the present embodiment has a structure that reflects the sound from the speaker 1701 through the reflection plate 1702 and radiates it to the outside of the vehicle. When the reflection plate 1702 is deformed due to the acoustic resonance, the reflection direction deviates from the narrow passage (air intake), and the reflected sound cannot be radiated to the outside of the vehicle, thereby deteriorating the sound pressure and sound quality. Therefore, the vehicle exterior sound reproduction device according to the present embodiment needs to have sufficiently high mechanical strength, and needs to suppress the acoustic resonance.

[0163] Therefore, in the present embodiment, the material and shape of the housing (at least the grille portion of the front side (or the sound outlet)) of the speaker 1701 and the reflector 1702, which are the main components, are optimized so that the impact of stones or the like entering the inside of the front bumper is borne and the acoustic resonance can be reduced. Regarding the material, the housing (at least the grille portion of the front side (or the sound outlet)) of the speaker 1701 and the reflector 1702 are made of, for example, high-strength engineering plastics such as glass-filled polycarbonate (PC). Engineering plastics have high internal losses and also help to reduce acoustic resonance. In addition, regarding the reduction of acoustic resonance, the shape of the reflector 1702 is optimized so that all frequency modes reach 200 Hz or higher, and the amplitude becomes sufficiently small for this frequency mode. In addition, a structure in which the grille portion of the speaker 1701 and the reflector 1702 are connected at three places is adopted. Obviously, a structure in which the grille portion of the speaker 1701 and the reflector 1702 are connected at four or more places can be adopted. In addition, a configuration is adopted in which the speaker 1701 is arranged to be directed to the rear side by using reflected sound, so the risk of damage to the speaker 1701 due to a direct impact from a stone or the like entering the inside of the front bumper can be significantly reduced.

[0164] Table 1 below shows the resonant frequency in each frequency mode of the reflection plate 1702 whose material and shape are optimized.

[0165] [Table 1]

[0166]

[0167]

[0168] As shown in Table 1, it can be understood that the material and shape are optimized so that all frequency modes reach 200 Hz or more, for which the amplitude becomes sufficiently small. In the first frequency mode, the resonant frequency is about 205 Hz, and in the second frequency mode, the resonant frequency is about 219 Hz. Fig.28 and 29The vibration simulation results of the reflector 1702 and the speaker 1701 (only the grille portion) in the first frequency mode and the second frequency mode are shown. Although the fifth reflection portion 1905 and the sixth reflection portion 1906 for the second stage reflection of high frequency sound waves are reflected by the eighth reflection portion 1908 and the tenth reflection portion 1910 (see, for example, Fig.19 ) are formed by tongues protruding from the outside, but they are cantilevered and have a larger amplitude than other parts.

[0169] C-3. Measurement results

[0170] In Section C-3, the performance of the exterior-vehicle sound reproducing apparatus according to the present embodiment described in Section C-1 above will be examined based on actual measurement results.

[0171] Fig.30 The result of measuring the sound pressure level of the sound (reflected sound) output from the vehicle exterior sound reproduction device according to the present embodiment by installing a microphone at a position specified in the R138 protocol regulations (2.0 m to the side from the vehicle's driving center line and at a height of 1.2 m above the ground) indicated by a black solid line in the figure is shown. For comparison, the sound pressure level in the case where the reflection plate 1702 is excluded is indicated by a gray solid line in the figure, and the sound pressure level of the sound (direct sound) output toward the front of the speaker 1701 (without the reflection plate 1702) is indicated by a black thin line in the figure. In the figure, the horizontal axis represents the frequency axis (Hz) and the vertical axis represents the sound pressure level (dB).

[0172] It can be understood that the sound pressure level of the reflected sound of the vehicle exterior sound reproduction device according to this embodiment (black solid line) is approximately equal to the sound pressure level of the direct sound when the speaker 1701 is directed to the front (without a reflector) (black thin dashed line). In other words, even when the sound is reflected by the reflector, the level that satisfies the sound pressure requirement of the vehicle exterior sound can be maintained.

[0173] In addition, when the sound pressure level (black solid line) of the vehicle exterior sound reproduction device according to the present embodiment is compared with the sound pressure level (gray solid line) in the case where there is no reflective plate, it can be confirmed that the improvement effect of 15 to 20 dB by utilizing the directivity control according to the reflection of the reflective plate is particularly in the high frequency range of 1 kHz or higher. In other words, in the case where the reflective plate 1702 is not provided, the sound pressure level cannot be maintained in the high frequency range.

[0174] Fig.31 and 32 The measurement results of the intensity of the sound (reflected sound) output from the exterior sound reproducing apparatus according to the present embodiment are shown. Fig.31 17 shows a view of the reflector plate 1702 viewed from the side, Fig.32A view of the reflection plate 1702 viewed from the upper side is shown. Here, the frequency of the output sound from the speaker 1701 is within the range of 1 kHz to 15 kHz.

[0175] exist Fig.31 and 32 In , arrows are used to represent vectors that indicate the direction of sound measured in terms of intensity. Here, shading is used to represent the sound pressure level, with darker arrows being used to draw the vectors where there is higher sound pressure, and lighter arrows being used where there is lower sound pressure.

[0176] Fig. 22 and 23 The results of the acoustic ray simulation based on the acoustic ray analysis are shown in Figure 2 (see Section C-2-1 above). Fig.31 and 32 and Fig. 22 and 23 When compared, it can be confirmed that, as a result of actual measurement of the intensity of the reproduced sound from the vehicle exterior sound reproducing apparatus according to the present embodiment, the sound is radiated in substantially the same direction as that of the simulation result.

[0177] Figures 33 to 36 The results of measuring the sound pressure level of the radiated sound from the vehicle exterior sound reproduction device according to the present embodiment by installing microphones at the positions specified in the R138 protocol regulations on the vehicle left front side (FL), the vehicle right front side (FR), the vehicle left rear side (RL), and the vehicle left and right sides (RR) (2.0 m laterally from the vehicle driving center line and 1.2 m above the ground). In each figure, the horizontal axis represents the frequency axis and the vertical axis represents the sound pressure level. The sound pressure level measured for each frequency band is represented by a black solid line, and as a comparison object, the background noise (dark noise) for each frequency band is represented by a gray solid line. According to the measurement results, it can be confirmed that the radiated sound of the vehicle exterior sound reproduction device according to the present embodiment shows a sufficient sound pressure level relative to the background noise on any of the vehicle left front side (FL), the vehicle right front side (FR), the vehicle left rear side (RL), and the vehicle left and right sides (RR).

[0178] C-4. Functional Configuration

[0179] C-4-1. First configuration example

[0180] Fig.37 The functional configuration of the vehicle exterior sound reproduction device according to the present embodiment is schematically shown. The illustrated vehicle exterior sound reproduction device 3700 includes a sound source section 3701, an equalizer (EQ) 3702, an amplification section 3703, a speaker section 3704, a reflection section 3705, a detection section 3706, an identification section 3707, and a control section 3708.

[0181] The sound source portion 3701 provides an audio signal. For example, although the audio signal is a notification sound of the AVAS, it may be, for example, audio for a person existing on the side of the vehicle, etc. The sound source portion 3701 may reproduce the audio signal from a recording medium such as a memory, etc., or may acquire the audio signal from the outside through radio communication, etc.

[0182] The equalizer 3702 performs equalization processing on the sound signal supplied from the sound source section 3701, and the amplification section 3703 performs amplification processing on the equalized sound signal.

[0183] like Fig.18 As shown, the speaker section 3704 is formed of a coaxial type speaker device in which a high-frequency speaker (tweeter) is installed on the front side of the center pole of a low-frequency speaker (woofer), and the speaker section 3704 can perform high-quality sound reproduction in a wide frequency range, and can radiate the sound output from the speaker covering each frequency band from the approximate center of the low-frequency speaker. Since the speaker section 3704 is installed on the outside of the vehicle, it has a waterproof function.

[0184] like Fig.19 As shown, the reflecting portion 3705 is arranged in front of the speaker 3704 (the radiation direction of the sound), and is formed by a reflecting plate having a plurality of reflecting surfaces that reflects the sound radiated from each of the woofer and tweeter in a coaxial form, and the reflecting portion 3705 radiates the sound to the outside of the vehicle, and passes through a narrow passage (air intake, etc.) and diffuses. Fig.37 In order to simplify the drawing, the detailed shape of the reflection plate is omitted. The reflection portion 3705 converges the sound rays output from the speaker 3704 to pass through a narrow passage (air intake, etc.), and reflects the sound rays to diffuse through the passage to the outside of the vehicle after being radiated.

[0185] The detection section 3706 is formed of vehicle-mounted sensors and the like. The vehicle-mounted sensors include an external recognition sensor, a vehicle interior sensor, and a vehicle sensor. The detection section 3706 may use some vehicle-mounted sensors provided in the vehicle control system (described above).

[0186] The recognition part 3707 recognizes events occurring in the vehicle based on the detection signal of the detection part 3706. The events occurring in the vehicle are various. Here, in the present embodiment, it is assumed that the recognition part 3707 recognizes at least events that require output of sounds outside the vehicle. Events that require output of sounds outside the vehicle include: the occurrence of events that require the generation of notification sounds of AVAS, such as the speed becoming the specified object vehicle speed specified in the R138 protocol; the occurrence of events that require the generation of warning sounds other than AVAS based on pedestrians approaching the vehicle and are unrelated to the vehicle speed; the occurrence of events that require notification responses, such as locking or opening doors, etc. The recognition part 3707 can perform recognition processing, for example, using a machine learning model that is learned through deep learning to estimate events on the vehicle based on detection signals.

[0187] The control section 3708 controls the driving of each of the sound source section 3701 , the equalizer 3702 , the amplification section 3703 , and the speaker section 3704 so as to generate an external vehicle sound having a volume, a pitch, a melody, etc. suitable for the event recognized by the recognition section 3707 .

[0188] The control section 3708 can control the driving of each section so that sounds with different tones and different melodies are reproduced according to the purpose such as the output of the notification sound of the AVAS, the response, etc. For example, the tone or melody of the vehicle approach notification sound can be switched between the case where the vehicle moves forward and the case where the vehicle moves backward. In addition, in the application of the response function, for example, the tone or melody of the reproduced sound can be finely switched between when locking the door and when unlocking the door.

[0189] C-4-2. Second configuration example

[0190] So far, the case where the reflection plate 1702 is fixed on the front surface of the speaker 1702 and the plurality of reflection surfaces included in the reflection plate 1702 have a fixed structure that does not change the posture has been described. From the viewpoint of radiation of the notification sound that satisfies the requirements specified in the R138 protocol provisions, the reflection plate 1702 having a fixed structure may be used. As a modification, by configuring the reflection plate 1702 as a type that is movable relative to the speaker 1701, and by configuring at least some of the plurality of reflection surfaces included in the reflection plate 1702 as a movable type, radiation direction control of the sound output from the speaker 1701 may be performed.

[0191] In the case where the off-vehicle sound reproduction device according to this embodiment has a direction control function for radiating sound, for example, such an application can be realized, that is, when there is a barbecue next to the vehicle, audio is transmitted in the direction where people are located, or notification sounds are transmitted to pedestrians in the direction of travel of the vehicle by changing the radiation direction of the sound according to the steering angle of the steering wheel.

[0192] Fig.38 The functional configuration of the vehicle exterior sound reproduction device according to the present embodiment is schematically shown in the case of performing directional control of radiated sound. The illustrated vehicle exterior sound reproduction device 3800 includes a sound source section 3801, an equalizer 3802, an amplification section 3803, a speaker section 3804, a reflection section 3805, a detection section 3806, an identification section 3807, and a control section 3808.

[0193] The sound source part 3801, the equalizer 3802, the amplification part 3803, the speaker part 3804, the detection part 3806 and the recognition part 3807 are Fig.37 The constituent elements with the same names shown in FIG. 1 are similar, so their description will be omitted here.

[0194] The reflecting portion 3805 converges the sound rays output from the speaker 3804 to pass through a narrow passage (air intake, etc.), and reflects the sound rays to diffuse after being radiated to the outside of the vehicle through the passage. Although the reflecting portion 3805 is arranged in front of the speaker 3804 (radiation direction of the sound), and is formed by a reflecting plate having a plurality of reflecting surfaces that reflect the sound radiated from each of the woofer and the tweeter in a coaxial form, the reflecting plate is configured to be movable, or at least some of the plurality of reflecting surfaces are configured to be movable.

[0195] The control part 3808 controls the drive of each of the sound source part 3801, the equalizer 3802, the amplification part 3803 and the speaker part 3804 and the drive of each part of the reflection part 3805 so as to generate an outside vehicle sound with a volume, tone, melody, etc. suitable for the event identified by the identification part 3807.

[0196] The control section 3808 can control the driving of each section so that sounds with different tones and different melodies are reproduced according to the purpose such as the output of the notification sound of the AVAS, the response, etc. For example, the tone or melody of the vehicle approach notification sound can be switched between the case where the vehicle moves forward and the case where the vehicle moves backward. In addition, in the application of the response function, for example, the tone or melody of the reproduced sound can be finely switched between when locking the door and when unlocking the door.

[0197] In addition, by using radiation direction control based on the drive of the reflection part 3805, the control part 3808 realizes such an application, that is, transmitting audio in the direction where people are when there is a barbecue next to the vehicle, or transmitting notification sound to pedestrians in the driving direction of the vehicle by changing the radiation direction of the sound according to the steering angle of the steering wheel.

[0198] [Industrial Applicability]

[0199] The present disclosure has been described in detail with reference to specific embodiments. However, it is obvious to those skilled in the art that modifications, substitutions, etc. may be made to the embodiments without departing from the essential spirit of the present disclosure.

[0200] In this specification, although the embodiment in which the vehicle exterior sound reproducing device according to the present disclosure is placed in the space inside the front bumper has been mainly described, the subject matter of the present disclosure is not limited thereto. For example, also in the case where the vehicle exterior sound generating device is configured by installing an exciter in a portion of the vehicle body other than the front cover (e.g., an intake duct, an undercover, etc.), similarly, a notification sound of an AVAS that meets the requirements specified in the R138 protocol regulations can be generated.

[0201] In addition, since the vehicle exterior sound reproducing device according to the present disclosure can reproduce high-quality sounds in a variety of ranges, sounds with different tones and different melodies can be reproduced according to the purpose such as output of notification sounds of AVAS, response, etc. In addition, the vehicle exterior sound reproducing device according to the present disclosure can transmit audio in the direction of people around the vehicle.

[0202] In summary, the present disclosure has been described in the form of examples, and the contents of this specification are not intended to be interpreted as limiting. The essential spirit of the present disclosure should be determined in consideration of the claims.

[0203] The present disclosure can also adopt the configurations described below.

[0204] (1) An exterior sound reproducing device includes a sound reproducing portion which is disposed inside a body member of a vehicle and emits sound to the exterior of the vehicle.

[0205] (2) The exterior sound reproducing device according to (1) above, wherein the sound reproducing portion includes an exciter, and the exciter is mounted on an inner wall of a body member of the vehicle.

[0206] (3) An exterior sound reproduction device according to (2) above, wherein the exciter is installed at a portion inside a main body part of the vehicle capable of outputting exterior sound that meets a predetermined required sound pressure level at a position having a predetermined distance and a predetermined height relative to a driving center line of the vehicle.

[0207] (4) The exterior sound reproduction device according to any one of (2) or (3) above, wherein the exciter is mounted at least one of an inner wall of a front bumper, an intake duct, and an undercover.

[0208] (5) The exterior sound reproducing apparatus according to any one of (2) to (4) above, wherein the exciter is mounted near a mounting position on an inner wall of a body member of the vehicle via a pedestal formed into a flat structure.

[0209] (6) The exterior sound reproducing device according to (1) above, wherein the sound reproducing portion includes a speaker and a reflection plate which is installed in front of the speaker and reflects radiated sound of the speaker.

[0210] (7) The exterior sound reproducing device according to (6) above, wherein the sound reproducing portion is disposed in a dead space in front of a radiator inside a front bumper.

[0211] (8) An exterior sound reproduction device according to any one of (6) or (7) above, wherein the reflection plate reflects the sound emitted by the speaker so that the sound is converged to be able to pass through a narrow passage provided in a main body part of the vehicle, and diffuses after passing through the narrow passage and being discharged to the outside of the vehicle.

[0212] (9) The exterior-vehicle sound reproducing device according to any one of (6) to (8) above, wherein the speaker includes a tweeter and a woofer coaxially arranged.

[0213] (10) The exterior sound reproducing device according to (9) above, wherein the reflection plate includes a high-frequency sound reflection surface that reflects the radiated sound from the tweeter and a low-frequency sound reflection surface that reflects the radiated sound from the woofer.

[0214] (11) An off-vehicle sound reproduction device according to (10) above, wherein the high-frequency sound reflecting surface has a concave-shaped reflecting portion and a convex-shaped reflecting portion, wherein the concave-shaped reflecting portion reflects the sound waves arriving from the high-frequency speaker to generate parallel waves, and the convex-shaped reflecting portion reflects the parallel waves to the side of a narrow channel connected to the outside of the vehicle and generates diffuse waves that diffuse after being discharged to the outside of the vehicle through the narrow channel.

[0215] (12) An outdoor sound reproduction device according to (11) above, wherein the high-frequency sound reflecting surface further has a concave-shaped reflecting portion, which reflects the sound waves transmitted from the high-frequency speaker directly to the narrow channel side and generates diffuse waves that diffuse after being discharged to the outside of the vehicle through the narrow channel.

[0216] (13) An exterior sound reproduction device according to any one of (10) to (12) above, wherein the low-frequency sound reflecting surface has a reflecting portion in a concave shape, and the reflecting portion in the concave shape reflects the sound waves transmitted from the low-frequency speaker directly to the narrow channel side, and generates a diffuse wave that diffuses after being discharged to the outside of the vehicle through the narrow channel.

[0217] (14) The exterior sound reproducing apparatus according to any one of (11) to (13) above, wherein the concave shape is formed by a parabolic curved surface having an appropriate opening ratio.

[0218] (15) The exterior sound reproducing apparatus according to any one of (10) to (14) above, wherein the low-frequency sound reflecting surface is disposed outside the high-frequency sound reflecting surface.

[0219] (16) The exterior sound reproducing device according to any one of (6) to (15) above, wherein at least one of the housing of the speaker and the reflection plate is made of glass-filled polycarbonate or another engineering plastic.

[0220] (17) The exterior sound reproduction device according to any one of (6) to (16) above, wherein the reflection plate is configured so that the resonance frequency is 200 Hz or higher in all frequency modes.

[0221] (18) The outside-vehicle sound reproducing apparatus according to any one of (1) to (17) above, further includes a control section that controls a sound reproducing operation performed using the sound reproducing section.

[0222] (19) The outside-vehicle sound reproducing device according to (18) above, wherein the control portion controls a sound reproducing operation performed using the sound reproducing portion according to an event occurring in the vehicle.

[0223] (19-1) An off-vehicle sound reproduction device according to (19) above, wherein the control portion controls a sound reproduction operation including at least one of a tone, a melody, and a radiation direction performed using the sound reproduction portion according to an event occurring in the vehicle.

[0224] (20) A vehicle device includes: a main body member; and a sound reproducing portion, the sound reproducing portion being disposed inside the main body member and radiating sound to the outside of the vehicle.

[0225] [Reference Symbol List]

[0226] 1201 intake pipe

[0227] 1202,1203 bottom cover

[0228] 1300 front bumper

[0229] 1301,1302 Exciter

[0230] 1400 Exterior sound reproduction equipment

[0231] 1401 Vehicle body parts

[0232] 1402 Exciter

[0233] 1403 Detection part

[0234] 1404 Identification section

[0235] 1405 drive control part

[0236] 1500, 1600, 1700 Exterior Sound Reproduction Equipment

[0237] 1701 Speaker

[0238] 1702 reflector

[0239] 1801 speaker (low frequency sound side)

[0240] 1802 speaker (high frequency sound side)

[0241] 3700 Exterior Sound Reproduction Equipment

[0242] 3701 Sound source part

[0243] 3702 Equalizer

[0244] 3703 Enlarged section

[0245] 3704 Speaker Part

[0246] 3705 reflection part

[0247] 3706 Detection Section

[0248] 3707 Identification Part

[0249] 3708 control part

[0250] 3800 Exterior Sound Reproduction Equipment

[0251] 3801 Sound source part

[0252] 3802 Equalizer

[0253] 3803 Enlarged section

[0254] 3804 speaker part

[0255] 3805 reflection part

[0256] 3806 detection part

[0257] 3807 Identification Part

[0258] 3808 control part

[0259] 3900 Exciter

[0260] 3901 Main part

[0261] 3902 frame part

[0262] 3903 wire

[0263] 4100 pedestal

Claims

1. An off-vehicle sound reproducing device, comprising a sound reproducing portion, the sound reproducing portion being arranged inside a body part of a vehicle and emitting sound to the outside of the vehicle. 2 . The exterior sound reproducing apparatus according to claim 1 , wherein the sound reproducing portion includes an exciter, and the exciter is mounted on an inner wall of a body member of the vehicle.

3. The exterior sound reproduction device according to claim 2, wherein the exciter is installed at a portion inside a main body part of the vehicle capable of outputting exterior sound that meets a predetermined required sound pressure level at a position having a predetermined distance and a predetermined height relative to a driving center line of the vehicle.

4. The exterior sound reproducing apparatus according to claim 2, wherein the exciter is installed at at least one portion of an inner wall of a front bumper, an intake duct, and an undercover. 5 . The exterior sound reproducing apparatus according to claim 2 , wherein the exciter is mounted in the vicinity of a mounting position of an inner wall of a body member of the vehicle via a pedestal formed into a flat structure. 6 . The exterior sound reproducing device according to claim 1 , wherein the sound reproducing portion includes a speaker and a reflection plate which is installed in front of the speaker and reflects radiated sound of the speaker.

7. The exterior sound reproducing apparatus according to claim 6, wherein the sound reproducing portion is disposed in a dead space in front of a radiator inside a front bumper.

8. The exterior sound reproducing device according to claim 6, wherein the reflection plate reflects the emitted sound of the speaker so that the sound is concentrated to be able to pass through a narrow passage provided in a body part of the vehicle, and diffuses after passing through the narrow passage and being discharged to the outside of the vehicle. 9 . The off-vehicle sound reproducing apparatus according to claim 6 , wherein the speaker comprises a tweeter and a woofer coaxially disposed. 10 . The exterior sound reproducing apparatus according to claim 9 , wherein the reflection plate includes a high-frequency sound reflection surface that reflects the radiated sound from the tweeter and a low-frequency sound reflection surface that reflects the radiated sound from the woofer.

11. The vehicle exterior sound reproduction device according to claim 10, wherein the high-frequency sound reflecting surface has a concave-shaped reflecting portion and a convex-shaped reflecting portion, wherein the concave-shaped reflecting portion reflects the sound waves arriving from the high-frequency speaker to generate parallel waves, and the convex-shaped reflecting portion reflects the parallel waves to the side of a narrow passage connected to the outside of the vehicle and generates diffuse waves that diffuse after being discharged to the outside of the vehicle through the narrow passage.

12. The vehicle exterior sound reproduction device according to claim 11, wherein the high-frequency sound reflecting surface further has a reflecting portion in a concave shape, which reflects the sound waves transmitted from the high-frequency speaker directly to the narrow passage side and generates a diffuse wave that diffuses after being discharged to the outside of the vehicle through the narrow passage.

13. The vehicle exterior sound reproducing device according to claim 10, wherein the low-frequency sound reflecting surface has a reflecting portion in a concave shape, which reflects the sound waves transmitted from the low-frequency speaker directly to the narrow passage side and generates a diffuse wave that diffuses after being discharged to the outside of the vehicle through the narrow passage.

14. The exterior sound reproducing apparatus according to claim 11, wherein the concave shape is formed by a parabolic curved surface having an appropriate opening ratio. 15 . The exterior sound reproducing apparatus according to claim 10 , wherein the low-frequency sound reflecting surface is disposed outside the high-frequency sound reflecting surface.

16. The exterior sound reproduction apparatus of claim 6, wherein at least one of the housing of the speaker and the reflector is composed of glass-filled polycarbonate or another engineering plastic. 17 . The exterior sound reproducing device according to claim 6 , wherein the reflection plate is configured so that the resonance frequency is 200 Hz or higher in all frequency modes.

18. The out-of-vehicle sound reproducing apparatus according to claim 1, further comprising a control section that controls a sound reproducing operation performed using the sound reproducing section.

19. The off-vehicle sound reproducing apparatus according to claim 18, wherein the control portion controls the sound reproducing operation performed using the sound reproducing portion according to an event occurring in the vehicle.

20. A vehicle device comprising: Main body parts; as well as The sound reproducing portion is disposed inside the main body member and radiates sound toward the outside of the vehicle.

Images