Anden Co., Ltd.

Toyota Jidosha Kabushiki Kaisha

Denso Electronics Corporation

Chikara Yamamoto

Haruyuki Tsuzuki

Tomonori Suzuki

Hironari Tajimi

Yukiko Matsubara

Hitoshi Sakamoto

Hiroshi Sakakibara

Yoshimitsu Ukai

Kazushi Yokota

Osamu Tateyama

Tadashi Matsui

A sound output device includes a waveform output unit and a sounding body. The waveform output unit is configured to output a sound waveform that includes a second waveform generated by a frequency modulation to a first waveform having a desired center frequency. The sounding body is configured to generate a sound corresponding to the sound waveform output from the waveform output unit.

Sound output device

An audio output device includes PWM output devices, a weighting unit, a mixer, and an amplifier. The PWM output devices divide audio data into multiple parts including an upper bit part to a lower bit part, and output the multiple parts of the audio data as PWM outputs. The weighting unit weights the PWM outputs from the PWM output devices. The mixer synthesizes the PWM outputs after being weighted. The amplifier supplies an electric current to a sounding body in accordance with a synthesis result by the mixer to cause the sounding body to emit a sound.

Audio output device

A vehicle approach notification device includes a speaker disposed between push-pull circuits. The push-pull circuits amplify power of a notification sound signal by their push-pull outputs, and output the amplified notification sound signal to the speaker so that the speaker emits a notification sound for notification of an approach of a vehicle. When the push-pull outputs of the push-pull circuits are stopped, and the microcomputer outputs a high-level signal between a common connection terminal and ground, the microcomputer determines that there is a wire-discontinuity failure in the speaker when a voltage between common connection terminals is equal to or higher than a predetermined value.

Vehicle approach notification device

A vehicle approach alert device includes: a memory memorizing a warning sound source data for emitting a warning sound from an external sound emitting unit and a canceling sound source data for emitting a canceling sound from an internal sound emitting unit. The canceling sound cancels the warning sound transmitted from the external sound emitting unit to inside of the vehicle. The vehicle approach alert device further includes: a control part configured to read the warning sound source data from the memory to cause the external sound emitting unit to emit the warning sound based on the warning sound source data, and to read the canceling sound source data from the memory to cause the internal sound emitting unit to emit the canceling sound based on the canceling sound source data to be synchronized with the warning sound.

Vehicle approach alert device

A vehicle approach alert device that outputs an approach report sound from a sounding body includes: a memory part in which data of the approach report sound is memorized; a signal generator that generates a voltage waveform signal of the approach report sound based on the data of the approach report sound; a calculator that calculates a temperature of the sounding body; and a correct part that corrects the approach report sound based on the temperature of the sounding body. The calculator acquires information about a temperature detected by a temperature sensor located at a position different from the sounding body in the vehicle, and estimates the temperature of the sounding body based on the temperature detected by the temperature sensor.

A vehicle approach alert device includes: a first output sound voltage waveform signal generator having a first output sound generator that generates a first signal corresponding to output sound data read out from a memory device, and a first sound volume variable device that controls a voltage level of the first signal; a second output sound voltage waveform signal generator having a second output sound generator that generates a second signal corresponding to the output sound data read out from the memory device, and a second sound volume variable device that controls a voltage level of the second signal; a mixer circuit that mixes the first signal and the second signal; and an amplifier that outputs a vehicle approach alert sound with flowing current, which corresponds to a voltage of a mixed signal, through a sound output body.

A vehicle approach warning apparatus for abnormality detection in various abnormal modes is provided. In the vehicle approach warning apparatus, a sound generator output from the microcomputer passes an AMP and HPF, and an output voltage corresponding to the sound generator output is applied to a speaker to emit vehicle approach sound. The vehicle approach warning apparatus includes a voltage sensor circuit and outputs a check usage output as the sound generator output at the abnormality detection. A single frequency output that is within a resonance frequency band of the speaker and that can be poorly reproduced by the speaker is used as the check usage output. The abnormality detection is performed based on whether an integration circuit voltage outputted from the voltage sensor circuit is within a voltage range being an abnormality determination threshold.

Vehicle approach warning apparatus

A vehicle proximity annunciator device reduces an occurrence of a pop noise without an additional circuit changing an output of a power amplifier. A capacitor is located between a connection point connecting multiple resistances generating a reference voltage and a ground terminal. The capacitor causes a rise-up time of the reference voltage to delay at a start of power supply to a power source terminal. A sound emission signal is increased at substantially a same level of the reference voltage so that a variation of a differential voltage between the reference voltage and the sound emission signal falls in a pre-determined range.

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Anjo, Japan

Chikara Yamamoto