Imasen Electric Industrial Co., Ltd.

Koichi Toyama

Toshihiko Kawamura

Yoshio Miyata

Katsunori Uchimura

Junjiro Yoshimura

Takashi Yamada

Tetsuo Momo

An electronic horn for use, e.g., in a vehicle, includes a piezoelectric element () that excites a plate-shaped oscillator (). A resonator () is provided with an opening () and covers forward of the oscillator such that a resonance space (S) is defined between the resonator and the oscillator. An inner cylinder () and an outer conical housing () are provided concentrically around the resonator. A circular cover () covers the inner cylinder () and the outer conical housing () from the front, such that a buffer chamber (BR), at least one first sound amplifying chamber (MH), and a second sound amplifying chamber (MH) are defined around an entire circumference of the opening of the resonator.

Electronic horn

An electronic horn includes a cover () on a front side of an intermediate element (). A first passage (P) within the horn is defined by a central portion () of the cover () that projects into a cylindrical interior of a cylindrical water-proofing wall (). Second passages (PPP) extend generally concentrically with respect to the first passage (P) and are respectively defined by water-proofing walls () that are formed on the cover () and project into the interior spaces of water-proofing walls (). The outermost second passage (P) opens toward the forward direction. The first and second passages (P-P) extend in a back-and-forth path that prevents any rainwater, which has entered the interior of the horn through the opening of the outermost second passage (P), from reaching a resonance space () defined between the resonator () and a sound-generating oscillator ().

An electronic vehicle horn outputs a warning sound by exciting a diaphragm using a piezoelectric device that is driven with a composite signal generated, in part, by modulating a first fundamental square wave with a first modulating square wave and setting a frequency deviation at the time of the modulation in a predetermined range, modulating a second fundamental square wave with a second modulating square wave and setting a frequency deviation at the time of the modulation in a predetermined range, and generating the composite signal by mixing the modulated first fundamental square wave and the modulated second fundamental square wave.

Growing community of inventors

Nagoya, Japan

Koichi Toyama