Warning device to indicate the state of gases exhaustion of a gas filter retaining dangerous gases

US4873970A · kind A · utility

Assignee

• Auergesellschaft GmbH · DE

Inventors

• Michael Freidank · Berlin, DE
• Jurgen Coym · Berlin, DE
• Axel Schubert · Munich, DE

Key dates

• Filing date: Mar 10, 1989
• Grant date: Oct 17, 1989
• Expiry date: Mar 10, 2009

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A62B18/088
• WIPO field: Other consumer goods
• WIPO sector: Other fields

Abstract

A warning device comprised of an electrochemical cell which detects the concentration of toxic gas that is passing through a housing holding the cell to a face mask. The cell produces a signal corresponding to the concentration level of toxic gas present. The signal is received by a threshold switch which is set to produce a signal only when a signal from the cell equals or exceeds a predetermined level. The signal from the threshold switch activates a visual signal means and acoustical signal means to indicate that a gas filter, connected to the warning device, is exhausted.