Riken Keiki Co., Ltd.

Riken Keiko Co., Ltd.

Seiichi Otani

Shoei Yasuda

Mamoru Furusato

Yukio Nakamura

Yoshikazu Shibasaki

A contact combustion-type gas sensor that can maintain its initial sensitivity over a long period of time in the presence of silicon vapor, wherein an induction portionof a gas detecting elementcontains not less than 30 percent by weight of an oxidation catalyst, and is aged in advance in an environment that contains silicon vapor serving as a poisoning substance.

Contact combustion gas sensor

A hydrogen sensorhas a fitting base platein which a gas-sensing chamberis formed, a specimen gas intakeformed on said fitting base plateopening toward an exit passageand introducing hydrogen gas into the gas-sensing chambera gas-sensing elementheld in the gas-sensing chamberand adapted to sense hydrogen gas, and a water-repelling filtercovering the specimen gas intake

Gas sensor

A gas detector-alarm comprises a hot-wire gas sensor having an actuating power control that supplies pulsed actuating power with a cycle T when the concentration of gas detected by the hot-wire gas sensor is lower than a first reference level, with a cycle T that is shorter than said cycle T at least once when the concentration of gas exceeds a second reference level, and with a cycle T again after an alarm has been triggered.

Growing community of inventors

Tokyo, Japan

Seiichi Otani