Hitachi, Ltd.

Katsuo Ohki

Akira Shimizu

Yasuo Otsuka

Kazutaka Sato

Taisaku Seino

Michihiro Watanabe

Hideyuki Kawase

Kazutoshi Konno

Hiromitsu Fukuda

Youichi Narui

Masahisa Aoyagi

Tsuguo Suzuki

Kimio Oga

Takahiro Daikoku

Masanori Watanabe

Yukiji Iwase

Osamu Sekiguchi

Tamotsu Tsukaguchi

Shinichi Shimode

Shigeru Koizumi

In an active noise-reduction controlling apparatus, there are provided a reference sensor for outputting a reference signal corresponding to information about a noise source, a noise-reduction error sensor for detecting a noise-reduction condition, an adding acoustic wave source controlled to produce an acoustic wave having the same amplitude as that of an acoustic wave received at the noise-reduction error sensor and having a phase opposite to that of the acoustic wave received as the noise-reduction error sensor; a first adaptive digital filter for processing the reference signal to output a control signal of the adding acoustic wave source, a second adaptive digital filter for setting a predicted value of a transfer function between an input signal of the adding acoustic wave source and an output signal of said noise-reduction error sensor, a filter coefficient controlling unit for optimizing a coefficient of the first adaptive digital filter with employment of the predicted value of the transfer function and the output of the noise-reduction error sensor, and a control unit for correcting the predicted value of the transfer function in accordance with an environmental change.

Method of actively controlling noise, and apparatus thereof

A facsimile apparatus has a lower structure and an upper structure which is swingable between a raised open position an a lowered close position about a pivot located at a lower part of the rear end portion of the apparatus. A thermal print head is fixed to the front end portion of the upper structure. A recording medium conveyor roller is fixed to the front end portion of the lower structure. A linear image sensor and an original sheet conveyor roller are fixed to a central portion of the lower structure. The recording medium is placed on the lower structure at a position between the thermal print head and the linear image sensor.

Facsimile apparatus

A facsimile apparatus has a lower structure and an upper structure which is swingable between a raised open position an a lowered closed position about a pivot located at a lower part of the rear end portion of the apparatus. A thermal print head is fixed to the front end portion of the upper structure. A recording medium conveyor roller is fixed to the front end portion of the lower structure. A linear image sensor and an original sheet conveyor roller are fixed to a central portion of the lower structure. The recording medium is placed on the lower structure at a position between the thermal print head and the linear image sensor.

Growing community of inventors

Ibaraki-ken, Japan

Katsuo Ohki