05038772 is referenced by 86 patents and cites 8 patents.

A closed-cycle breathing equipment and gas mask for operation under pressure with a pressurized air source for respiratory air and with an air bag being under prestress during the inspiration phase includes an arrangement where the prestress is decreased by a control element recognizing the expiratory phase and so as to support respiration during the expiration phase. A pneumatic control valve is used which can switch connections between the inspiration and the expiration phase and which is directly controlled by the difference between the exhalation pressure and the pressure in the air bag. The control valve connects the pressurized air source with the air bag during the inspiration phase and during the expiration phase it interrupts the connection due to the occurring dynamic pressure of the pressurized air from the pressurized air source and thus actuates a pneumatic adjusting element so that the mechanical prestress at the air bag is reduced.

Title
Closed-cycle breathing equipment
Application Number
7/368870
Publication Number
5038772
Application Date
June 20, 1989
Publication Date
August 13, 1991
Inventor
Hans Burkhardt Fiedler
Lubeck
DE
Karsten Vogeler
Brunsbeck
DE
Wolfgang Drews
Zarpen
DE
Hasso Weinmann
Lubeck
DE
Norbert Kollenbrandt
Berkenthin
DE
Ernst Gunther Kolbe
Molln
DE
Agent
McGlew & Tuttle
Assignee
Dragerwerk Aktiengessellschaft
GB
IPC
A61M 16/00
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