Loudspeaker system
By designing a speaker system that can switch the speaker array area in the vehicle notification device, the problem that the prior art cannot switch the audio output range is solved, and the function of automatically adjusting the audio output range according to the vehicle driving condition is realized.
Patent Information
- Application Number
- CN202411642660.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-11-24
- Filing Date
- 2024-11-18
- Publication Date
- 2025-05-27
AI Technical Summary
The existing vehicle notification device cannot switch the output range of the notification by adjusting the sound wave phase of the speaker array, and cannot switch to long-distance output or large-range output according to the driving conditions of the vehicle.
A speaker system is designed, including an output sound generation mechanism, a speaker array, a speaker switching mechanism and a switching indication mechanism. By switching the number and layout of speakers in different areas of the speaker array, the direction characteristics of the speaker array are achieved from wide to narrow, thereby switching the output range of sound.
It is realized that the output range of the speaker array is automatically switched according to the vehicle's driving speed, driving position or peripheral conditions, thereby more effectively notifying the approach of surrounding personnel and vehicles.
Smart Images
Figure CN120050578A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a speaker system composed of a plurality of speakers. Background Art
[0002] Conventionally, there is known a vehicle presence notification device that uses a speaker array composed of a plurality of ultrasonic speakers and adjusts the phase of sound waves output from each ultrasonic speaker to change the directivity of the notification sound (see, for example, Patent Document 1).
[0003] Prior art literature:
[0004] Patent Literature:
[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-31695 Summary of the invention
[0006] Problems to be solved by the invention:
[0007] In addition, the vehicle presence notification device disclosed in the above-mentioned patent document 1 can change the directivity of the entire speaker array by adjusting the phase of the sound waves output from each speaker constituting the speaker array, but cannot change the output range of the notification sound. For example, it is impossible to switch between outputting sound toward a long distance and outputting sound toward a wide range around the vehicle according to the condition of the moving vehicle.
[0008] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a speaker system capable of switching a sound output range.
[0009] Means used to solve the problem:
[0010] In order to solve the above-mentioned problems, the speaker system of the present invention comprises: an output sound generating mechanism that generates sound as an output object; a speaker array that includes a plurality of speakers that can selectively input the generated sound of the output sound generating mechanism; a speaker switching mechanism that switches one or more speakers that input the generated sound; and a switching instruction mechanism that issues a switching instruction to the speaker switching mechanism in accordance with the width of the directional characteristics of the sound output from the speaker array. Specifically, the above-mentioned speaker switching mechanism selectively switches between a first area having a large area and including a large number of speakers and a second area having a small area and including a small number of speakers.
[0011] By using speakers contained in a smaller area from among the multiple speakers constituting the speaker array, the directional characteristics of the speaker array become wider, and by using speakers contained in a larger area, the directional characteristics of the speaker array become narrower. Therefore, by switching the area where the speakers are configured, the output range of the radiated sound of the speaker array can be switched.
[0012] Preferably, the device further comprises a surrounding situation determination unit for determining the surrounding situation, and the switching instruction unit performs switching instruction based on the surrounding situation determined by the surrounding situation determination unit. Thus, the width of the directional characteristic can be automatically switched according to the surrounding situation.
[0013] In addition, preferably, the speaker system is mounted on the vehicle, and outputs a sound notifying the approach of the vehicle to people around, the surrounding condition judgment means is a speed acquisition means that acquires the running speed of the vehicle, and the switching instruction means performs a switching instruction, and the switching instruction is that when the running speed acquired by the speed acquisition means is fast, the first area is selected to narrow the directional characteristics of the sound output from the speaker array, and when the running speed acquired by the speed acquisition means is slow, the second area is selected to widen the directional characteristics of the sound output from the speaker array. Thereby, when the vehicle is running at a low speed, pedestrians and the like around the vehicle can widely hear the sound notifying the approach of the vehicle, and when the vehicle is running at a medium speed or above, pedestrians and the like in a slightly distant place can hear the sound notifying the approach of the vehicle.
[0014] In addition, preferably, the speaker system is mounted on the vehicle, and outputs a sound notifying the approach of the vehicle to people around, the surrounding condition judging means is a driving environment judging means for judging whether the driving position of the vehicle is an urban built-up area or a suburb, and the switching indication means performs a switching indication, and the switching indication is that when the driving environment judging means judges that the driving position of the vehicle is in the suburbs, the first area is selected to narrow the directional characteristics of the sound output from the speaker array, and when the driving environment judging means judges that the driving position of the vehicle is in the urban built-up area, the second area is selected to widen the directional characteristics of the sound output from the speaker array. Thus, in an urban built-up area where there is a high probability that there are many pedestrians around the vehicle, the pedestrians around the vehicle can widely hear the sound notifying the approach, and in a suburb where there are relatively few people, the pedestrians in a slightly distant place can hear the sound notifying the approach of the vehicle.
[0015] Preferably, the switching instruction means performs switching instructions to alternately select the first area and the second area. Thus, the sound emitted by the speaker array can be heard in both nearby and far spaces.
[0016] In addition, preferably, the surrounding condition judgment means has a camera means for photographing the surroundings, and an image analysis means for analyzing the surrounding conditions based on the image obtained by the camera means, and the switching instruction means performs a switching instruction for selecting one of the first area and the second area based on the surrounding conditions analyzed by the image analysis means. Thus, the width of the directional characteristics of the radiated sound of the speaker array can be switched based on the accurate understanding of the surrounding conditions.
[0017] In addition, preferably, the surrounding condition judging means is a crowding state judging means for judging the crowding state of the surrounding, and the switching instruction means performs a switching instruction for selecting one of the first area and the second area based on the crowding state of the surrounding judged by the crowding state judging means. Thus, the width of the directional characteristics of the radiated sound of the speaker array can be switched according to the crowding state of the surrounding. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 It is a diagram showing the structure of a vehicle approach notification device according to one embodiment.
[0019] Figure 2 It is a diagram showing the structure of a speaker array.
[0020] Figure 3 This is a diagram for explaining the correspondence between the width of the directivity characteristic and the speakers used.
[0021] Figure 4 It is an explanatory diagram of the sound field when the directivity characteristics are switched.
[0022] Figure 5 FIG. 1 is a diagram showing a modified example of the area N set for the speaker array.
[0023] Figure 6 It is a diagram showing another modification example of the area N set for the speaker array.
[0024] Figure 7 FIG. 1 is a diagram showing a modified example of the area W set for the speaker array.
[0025] Figure 8 It is a diagram showing another modification example of the areas N and W set for the speaker array.
[0026] Fig. 9 This is a diagram showing a specific example in which the directional characteristics of the speaker array are switched according to the traveling speed of the vehicle.
[0027] Fig.10 This is a diagram showing a specific example of switching the directional characteristics of the speaker array depending on whether the vehicle's driving position is in an urban built-up area or in the suburbs.
[0028] Fig.11 This is a diagram showing a specific example of determining the surrounding situation based on an image obtained by capturing the surrounding area.
[0029] Fig.12 It is a diagram showing a modified example in which the directional characteristics of the speaker array are made variable according to the crowded state in the room.
[0030] Description of reference numerals:
[0031] 100, 100A, 100B, 100C Vehicle approach notification device
[0032] 100D Broadcasting Device
[0033] 110 Driving sound generation unit
[0034] 110D Broadcast Sound Generation Unit
[0035] 120 speaker array
[0036] 122 speakers
[0037] 130SP (speaker) driver
[0038] 140, 140A, 140B, 140C, 140D switching control unit
[0039] 150 Surrounding Condition Judgment Department
[0040] 150A speed acquisition unit
[0041] 150B Driving environment judgment unit
[0042] 150C Image Analysis Department
[0043] 150D Congestion Status Judgment Unit
[0044] 152 Camera DETAILED DESCRIPTION
[0045] Hereinafter, a vehicle approach notification device according to an embodiment of the speaker system of the present invention will be described with reference to the drawings.
[0046] Figure 1 It is a diagram showing the structure of a vehicle approach notification device according to one embodiment. Figure 1 The vehicle approach notification device 100 shown is mounted on a vehicle with a quiet driving sound (e.g., an electric car) and is used to output a virtual driving sound to the surrounding of the vehicle to notify the surrounding pedestrians of the vehicle approaching. To this end, the vehicle approach notification device 100 includes a driving sound generating unit 110, a speaker array 120, an SP (speaker) driving unit 130, a switching control unit 140, and a surrounding condition determining unit 150.
[0047] The driving sound generating unit 110 generates a predetermined sound for notifying pedestrians around the vehicle of the approach of the vehicle. The generated sound is assumed to be a virtual driving sound of the vehicle, but its purpose is to notify the approach of the vehicle by sound, so it does not necessarily have to be similar to the driving sound, and may be other notification sounds.
[0048] The speaker array 120 includes a plurality of speakers to which the generated sound output from the running sound generating unit 110 is selectively input, and is provided at the front of the vehicle. Each speaker is, for example, an ultrasonic speaker, and emits sound in the audible range corresponding to the input generated sound.
[0049] Speaker 122( Figure 2 ) utilizes the waveform distortion generated by radiating two types of ultrasonic waves with high sound pressure to reproduce audible sound with narrow directional characteristics. If the frequency of the ultrasonic wave (carrier) of one side is set to f1, distortion components of integer multiples of 2f1, 3f1, 4f1, ... are generated. In addition, if the frequency of the ultrasonic wave (carrier) of the other side is set to f2, distortion components of integer multiples of 2f2, 3f2, 4f2, ... are generated. In the case where the frequencies f1 and f2 are both ultrasonic waves (sounds with frequencies higher than the human audible range), the frequencies of these integer multiple distortions are also higher than the audible range, so they cannot be heard by the human ear. However, in the case of radiating such two types of ultrasonic waves of carrier waves at the same time, the difference sound (frequency is f2-f1) and the harmony sound (frequency is f1+f2) components are generated. Among them, by setting the frequency (f2-f1) of the difference sound to be within the audible range, the generated sound as audible sound can be radiated from the ultrasonic speaker 122. For example, if f1 is set to 41 kHz and f2 is set to 40 kHz, a difference sound of f2 - f1 = 1 kHz can be radiated.
[0050] Figure 2 is a diagram showing the structure of the speaker array 120. Figure 2 As shown, in the speaker array 120 of the present embodiment, a total of 64 ultrasonic speakers 122 are arranged without gaps in 8 rows and 8 columns.
[0051] The SP driving unit 130 can selectively input a signal obtained by amplifying the sound generated by the driving sound generating unit 110 to one or more speakers 122 included in the speaker array 120, and by changing the selection state, the width of the area where the one or more speakers 122 emitting sound are configured is switched.
[0052] The switching control unit 140 instructs the SP driving unit 130 to switch the area (effective area) including the speakers 122 that emit sound, according to the width or narrowness of the directional characteristics of the sound output from the speaker array 120 .
[0053] The surrounding situation determination unit 150 determines the surrounding situation. Based on the surrounding situation determined by the surrounding situation determination unit 150, the switching control unit 140 issues a switching instruction.
[0054] The running sound generating unit 110 described above corresponds to the output sound generating means, the SP driving unit 130 corresponds to the speaker switching means, the switching control unit 140 corresponds to the switching instruction means, and the surrounding situation determining unit 150 corresponds to the surrounding situation determining means.
[0055] The vehicle approach notification device 100 of the present embodiment has such a configuration, and the operation of switching the width of the directional characteristic will be described below.
[0056] Figure 3 It is a diagram for explaining the correspondence between the width of the directivity characteristic and the loudspeaker 122 used. Figure 3 (A) shows an example of using the loudspeaker 122 in a case where the directional characteristics are widened. Figure 3 (B) shows an example of using the loudspeaker 122 when the directivity characteristic is narrowed.
[0057] In order to make the directivity characteristics wider, it is necessary to reduce the number of speakers 122 that emit sound and to reduce the area where these speakers 122 are arranged. Figure 3 In (A), a small number of speakers 122 (4×4=16 in the center) included in the smaller area N (the second area) are selected, and sound is radiated from these 16 speakers 122 .
[0058] On the other hand, if it is desired to narrow the directional characteristics, it is necessary to increase the number of speakers 122 that emit sound and to enlarge the area where these speakers 122 are arranged. Figure 3 In (B), a large number of speakers 122 (a total of 8×8=64) included in the larger area W (the first area) are selected, and sound is radiated from these 64 speakers 122.
[0059] Figure 4 is an illustration of the sound field when the directional characteristics are switched. Figure 4 As shown in (A), by Figure 3 The small number of speakers 122 included in (A)) can emit sound and obtain a wide directional characteristic, so the sound is radiated to a wide range from the speaker array 120 installed in the front of the vehicle. In this case, the sound is widely diffused, and the sound is easily attenuated along the radiation direction, so pedestrians and the like at a close distance can hear the sound.
[0060] On the other hand, Figure 4 As shown in (B), by Figure 3The large number of speakers 122 included in (B)) can emit sound and obtain a narrow directional characteristic, so the sound is radiated toward a small range from the speaker array 120 installed in the front of the vehicle. In this case, the sound diffusion is small, the sound is difficult to attenuate along the radiation direction, and pedestrians and the like at a long distance can hear the sound.
[0061] In this way, by using the speakers 122 included in the smaller area N from among the multiple speakers 122 constituting the speaker array 120, the directional characteristics of the speaker array 120 become wider, and by using the speakers 122 included in the larger area W, the directional characteristics of the speaker array 120 become narrower. Therefore, by switching the areas N and W where the speakers 122 are configured, the output range of the radiated sound of the speaker array 120 can be switched.
[0062] Figure 5 FIG. 1 is a diagram showing a modified example of the area N set for the speaker array 120. Figure 5 The region N with wide directional characteristics shown in (A) includes 8×4=32 loudspeakers 122. By radiating sound from these loudspeakers 122, the lateral directional characteristics can be widened and the longitudinal directional characteristics can be narrowed. Figure 5 The narrow directivity area W shown in (B) is Figure 3 The same as shown in (B).
[0063] Figure 6 FIG. 2 is a diagram showing another modification example of the area N set for the speaker array 120 . Figure 6 The area N with wide directional characteristics shown in (A) has a trapezoidal shape with a short bottom side and a long top side, and includes a total of 20 speakers 122. By radiating sound from these speakers 122, the lateral directional characteristics can be narrowed near the top side where 8 speakers 122 are arranged in the horizontal direction, and the lateral directional characteristics can be widened near the bottom side where 2 speakers 122 are arranged in the horizontal direction. In addition, Figure 6 The narrow directivity area W shown in (B) is Figure 3 The same as shown in (B).
[0064] Figure 7 FIG. 1 is a diagram showing a modified example of the area W set for the speaker array 120. Figure 7 The narrow directional characteristic area W shown in (B) includes 48 loudspeakers 122 in two rows along the periphery. By radiating sound from these loudspeakers 122, Figure 3 The same as the case shown in (B) can narrow the directivity characteristics. Figure 7 The wide directivity area N shown in (A) is Figure 3 The same as shown in (A).
[0065] Figure 8 FIG. 1 is a diagram showing another modification example of the areas N and W set for the speaker array 120. Figure 8 In the wide directional characteristics of the areas N1 and N2 shown in (A), there are 8×8=64 speakers 122 as a whole, but the output sound pressure of the 4×4=16 speakers 122 in the central area N1 becomes larger, while the output sound pressure of the 48 speakers 122 in the surrounding area N2 becomes smaller. Figure 8 In the narrow directional characteristics areas W1 and W2 shown in (B), there are 8×8=64 speakers 122 as a whole, but the output sound pressure of the 4×4=16 speakers 122 in the central area W1 becomes smaller, while the output sound pressure of the 48 speakers 122 in the peripheral area W2 becomes larger. In this way, even if the number of speakers 122 used is the same, by setting the central area N1 including the speakers 122 with high sound pressure, the directional characteristics of the speaker array 120 can be widened, and by setting the peripheral area W2 including the speakers 122 with high sound pressure, the directional characteristics of the speaker array 120 can be narrowed.
[0066] Next, a specific example of the surrounding situation determination unit 150 will be described.
[0067] Fig. 9 This is a diagram showing a specific example in which the directional characteristics of the speaker array 120 are switched according to the traveling speed of the vehicle. Fig. 9 The vehicle approach notification device 100A shown in FIG. Figure 1 The vehicle approach notification device 100 shown is different in that the surrounding situation determination unit 150 is realized by a speed acquisition unit 150A and the switching control unit 140 is replaced by a switching control unit 140A. The speed acquisition unit 150A corresponds to the speed acquisition means.
[0068] The speed acquisition unit 150A acquires the running speed of the vehicle. For example, it is possible to detect the running speed based on the vehicle speed pulse outputted at each certain running distance, or to acquire the running speed from the vehicle control unit or the like that performs display processing such as a speedometer, etc. In addition, the relative speed of pedestrians and the like around the vehicle changes in accordance with the running speed of the vehicle, so in this specification, etc., it is assumed that the running speed of the vehicle is also included in the "surrounding conditions".
[0069] The switching control unit 140A issues a switching instruction to the SP driving unit 130, and the switching instruction is to select area W to narrow the directional characteristics of the sound output from the speaker array 120 when the driving speed obtained by the speed acquisition unit 150A is fast, and to select area N to widen the directional characteristics of the sound output from the speaker array 120 when the driving speed obtained by the speed acquisition unit 150A is slow.
[0070] Thus, when the vehicle is traveling at a low speed, pedestrians and the like around the vehicle can widely hear the sound notifying the approach of the vehicle, and when the vehicle is traveling at a medium speed or higher, pedestrians and the like at a slightly distant location can hear the sound notifying the approach of the vehicle.
[0071] Fig.10 This is a diagram showing a specific example of switching the directional characteristics of the speaker array 120 depending on whether the vehicle's driving position is in an urban built-up area or in the suburbs. Fig.10 The vehicle approach notification device 100B shown is Figure 1 The vehicle approach notification device 100 shown is different in that the surrounding condition determination unit 150 is realized by a driving environment determination unit 150B and the switching control unit 140 is replaced by a switching control unit 140B. The driving environment determination unit 150B corresponds to the driving environment determination means.
[0072] The driving environment determination unit 150B determines whether the driving position of the vehicle is a built-up area or a suburb. For example, a vehicle navigation device that processes whether the vehicle position is included in a built-up area or a suburb based on map data continuously or at regular intervals can be used as the driving environment determination unit 150B, or information indicating whether the vehicle is traveling in a built-up area or a suburb is obtained from the vehicle navigation device.
[0073] The switching control unit 140B issues a switching instruction to the SP driving unit 130, and the switching instruction is that when the driving environment judgment unit 150B judges that the driving position of the vehicle is in the suburbs, the area W is selected to narrow the directional characteristics of the sound output from the speaker array 120, and when the driving environment judgment unit 150B judges that the driving position of the vehicle is in an urban built-up area, the area N is selected to widen the directional characteristics of the sound output from the speaker array 120.
[0074] As a result, in urban built-up areas where there is a high probability that there are many pedestrians around the vehicle, the pedestrians around the vehicle can widely hear the sound notifying the approach of the vehicle, while in suburban areas where there are fewer people, pedestrians in slightly more distant places can hear the sound notifying the approach of the vehicle.
[0075] Fig.11 This is a diagram showing a specific example of determining the surrounding situation based on an image obtained by capturing the surrounding area. Fig.11 The vehicle approach notification device 100C shown is Figure 1 The vehicle approach notification device 100 shown is different in that the surrounding situation determination unit 150 is realized by a camera 152 and an image analysis unit 150C, and the switching control unit 140 is replaced by a switching control unit 140C. The camera 152 corresponds to the imaging means, and the image analysis unit 150C corresponds to the image analysis mechanism.
[0076] One or more cameras 152 are installed at the front or side of the vehicle to capture images of the surrounding area including at least the front of the vehicle. The image analysis unit 150C analyzes the position and number of pedestrians and the like around the vehicle, or the width of the road and the lane, etc., of the vehicle, based on the images captured by the camera 152.
[0077] Based on the conditions around the vehicle analyzed by the image analysis unit 150C, the switching control unit 140C instructs the SP driving unit 130 to switch between the area W where the directional characteristics of the sound output from the speaker array 120 become narrower and the area N where the directional characteristics of the sound output from the speaker array 120 become wider.
[0078] For example, if the result of analyzing the image is that there are many pedestrians around the vehicle, the area N where the directional characteristics are widened is selected, and otherwise the area W where the directional characteristics are narrowed is selected. In this way, the width of the directional characteristics of the sound radiated by the speaker array 120 can be switched based on the accurate understanding of the surrounding conditions. In addition, the image captured can be analyzed and compared with the Fig. 9 The same processing as that of the speed acquisition unit 150A shown in FIG. Fig.10 The same processing is performed by the running environment determination unit 150B shown.
[0079] Fig.12 It is a diagram showing a modified example in which the directional characteristics of the speaker array 120 are made variable according to the crowded state in the room. Fig.12 The broadcasting device 100D shown is installed in a sales floor of a department store, for example, and emits a predetermined broadcast voice to a portion of customers. Figure 1 The vehicle approach notification device 100 shown in FIG. 1 is similar in structure to the vehicle approach notification device 100 shown in FIG. 1 , and is different from the vehicle approach notification device 100 in that the surrounding condition determination unit 150 is implemented by a congestion state determination unit 150D, and the running sound generation unit 110 is replaced by a broadcast sound generation unit 110D, and the switching control unit 140 is replaced by a switching control unit 140D. The broadcast sound generation unit 110D corresponds to the output sound generation unit, and the congestion state determination unit 150D corresponds to the congestion state determination unit.
[0080] The congestion state determination unit 150D determines the congestion state of customers in the surrounding area (specific area in the department store). Fig.11 The image analysis unit 150C shown in the figure similarly analyzes the captured image of the camera 152 to make the above determination, or a sensor is installed at the entrance to detect the entry and exit of customers and the above determination is made based on the detection result.
[0081] The switching control unit 140D instructs the SP driving unit 130, based on the surrounding congestion state determined by the congestion state determination unit 150D, to switch between the area W where the directional characteristics of the broadcast sound output from the speaker array 120 become narrower and the area N where the directional characteristics of the broadcast sound output from the speaker array 120 become wider.
[0082] For example, when the number of customers in a specific area is small and the crowd is relaxed, in order to attract customers, the area N is selected so that the directional characteristics of the radiated broadcast sound are widened, and when the number of customers in a specific area is large and the crowd is crowded, in order to allow only certain customers to hear the radiated broadcast sound, the area W is selected so that the directional characteristics of the radiated broadcast sound are narrowed. In this way, the width of the directional characteristics of the radiated sound of the speaker array 120 can be switched according to the surrounding crowded state.
[0083] in addition, Fig.12 The broadcasting device 100D shown can also be used in situations other than the broadcasting sound in a department store. For example, in an art museum, when there are many students in the exhibition room and it is crowded during a student study tour, the area N that makes the directional characteristics of the radiated broadcast sound wider is selected, and in other normal situations, the area W that makes the directional characteristics of the radiated broadcast sound narrower is selected.
[0084] In addition, the present invention is not limited to the above-mentioned embodiment, and various modifications can be implemented within the scope of the main purpose of the present invention. In the above-mentioned embodiment, one of the wide directivity characteristics corresponding to the area N and the narrow directivity characteristics corresponding to the area W is selected, but the area N and the area W can be alternately switched at a predetermined time to repeatedly realize the wide directivity characteristics and the narrow directivity characteristics of the radiated sound of the speaker array 120. In this way, the radiated sound of the speaker array 120 can be heard in both the near and far spaces around.
[0085] In the above-described embodiment, the speaker array 120 is configured using the ultrasonic speakers 122 . However, the speaker array 120 may be configured using speakers other than ultrasonic speakers (speakers that directly output sounds in the audible range).
[0086] Industrial Applicability:
[0087] As described above, according to the present invention, by using speakers contained in a smaller area from among a plurality of speakers constituting the speaker array, the directional characteristics of the speaker array become wider, and by using speakers contained in a larger area, the directional characteristics of the speaker array become narrower. Therefore, by switching the area in which the speakers are configured, the output range of the radiated sound of the speaker array can be switched.
Claims
1. A speaker system, characterized in that: have: An output sound generating mechanism generates a sound as an output object; a speaker array including a plurality of speakers capable of selectively inputting the generated sound of the output sound generating mechanism; A speaker switching mechanism switches one or more of the speakers that input the generated sound; as well as The switching instruction means issues a switching instruction to the speaker switching means according to the width or narrowness of the directional characteristics of the sound output from the speaker array.
2. The speaker system according to claim 1, characterized in that The speaker switching mechanism selectively switches between a first area having a large area and including a large number of the speakers and a second area having a small area and including a small number of the speakers.
3. The speaker system according to claim 2, characterized in that Also available: The surrounding situation judgment mechanism judges the surrounding situation. The switching instruction means issues a switching instruction based on the surrounding conditions determined by the surrounding condition determination means.
4. The speaker system according to claim 3, characterized in that The speaker system is mounted on a vehicle and outputs a sound to notify surrounding people of the approach of the vehicle. The surrounding condition determination means is a speed acquisition means for acquiring the running speed of the vehicle. The switching indication mechanism performs a switching indication, wherein when the traveling speed obtained by the speed obtaining mechanism is fast, the first area is selected to narrow the directional characteristics of the sound output from the speaker array, and when the traveling speed obtained by the speed obtaining mechanism is slow, the second area is selected to widen the directional characteristics of the sound output from the speaker array.
5. The speaker system according to claim 3, characterized in that The speaker system is mounted on a vehicle and outputs a sound to notify surrounding people of the approach of the vehicle. The surrounding condition judgment unit is a driving environment judgment unit for judging whether the driving position of the vehicle is a built-up area in a city or a suburb. The switching indication mechanism performs a switching indication, wherein when the driving environment judgment mechanism determines that the driving position of the vehicle is in the suburbs, the first area is selected to narrow the directional characteristics of the sound output from the speaker array, and when the driving environment judgment mechanism determines that the driving position of the vehicle is in an urban built-up area, the second area is selected to widen the directional characteristics of the sound output from the speaker array.
6. The speaker system according to claim 2, characterized in that The switching instruction means performs a switching instruction to alternately select the first area and the second area.
7. The speaker system according to claim 3, characterized in that The surrounding situation determination means includes a camera for photographing the surroundings, and an image analysis means for analyzing the surrounding situation based on the image obtained by the camera. The switching instruction means issues a switching instruction to select one of the first area and the second area based on the surrounding conditions analyzed by the image analyzing means.
8. The speaker system according to claim 3, characterized in that The surrounding condition judging means is a congestion state judging means for judging the surrounding congestion state. The switching instruction means issues a switching instruction to select one of the first area and the second area based on the surrounding congestion state determined by the congestion state determination means.
Citation Information
Patent Citations
Vehicle presence informing device
JP2011031695A