| 摘要 |
A vehicle presence notification apparatus uses several ultrasonic transducer devices to generate a notice sound by emitting an ultrasonic wave in mid air based on an ultrasonic signal modulated according to an audible sound. At least one of the speaker-use ultrasonic transducer devices is a two-way transducer device that is enabled to perform not only transmission but also reception of an ultrasonic wave. When a vehicle velocity is equal to or greater than a predetermined value, the two-way transducer device is caused to function as an ultrasonic sensor. Thus, even when the generation of any notice sound is unnecessary due to the vehicle velocity being fast, the vehicle presence notification apparatus can be used as an ultrasonic sensor to measure a distance with an obstacle outside of the vehicle.
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