Excess pressure respirator with pressurized breathing gas shutoff

US4364384A · kind A · utility

Assignee

• DRAGERWERK AKTIEGESELLSCHAFT · DE

Inventors

• Ernst Warncke
• Adalbert Pasternack · Bad Schwartau, DE

Key dates

• Filing date: Mar 30, 1981
• Grant date: Dec 21, 1982
• Expiry date: Mar 30, 2001

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A62B7/08
• WIPO field: Other consumer goods
• WIPO sector: Other fields

Abstract

An excess pressure respirator with automatic or manual shutoff valve is disclosed. A breathing bag having at least one movable plate member is utilized to receive and supply breathing air from a user. The plate member is biased to reduce the volume of the bag and apply pressure to the contents of the bag. A pressurized gas source is connected through a connecting line to the bag. A dosing valve is positioned in the connecting line to be opened when the volume of the bag is reduced during an inhalation cycle and then closed so that a dosed quantity of oxygen is supplied to the bag. A shutoff valve is also provided in the connection for shutting flow of breathing gas from the source entirely when the bag falls below a minimum volume which is indicative of a large leak or the removal of a gas mask from the user's face. A manual shutoff may also be provided in the form of a movable block which stops the movement of the biased plate member before it engages the dosing valve to open it.