초록 ▼

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 expirato

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.

대표청구항 ▼

A closed cycle breathing apparatus, comprising: a pressurized air source; a bellows-type breathing bag; an inspiration line connected to said breathing bag; an expiration line connected to said breathing bag; prestress means for applying a force to said breathing bag for contracting said breathing b

A closed cycle breathing apparatus, comprising: a pressurized air source; a bellows-type breathing bag; an inspiration line connected to said breathing bag; an expiration line connected to said breathing bag; prestress means for applying a force to said breathing bag for contracting said breathing bag to urge air out of said breathing bag; control means for counter-acting said prestress means allowing expansion of said breathing bag during expiration including a pneumatic control valve means connected to said exhalation line and connected to said breathing bag for responding to a difference between gas pressure in said exhalation line and gas pressure in said breathing bag for switching between an inspiration phase and an expiration phase based on said difference and for connecting said pressurized breathing source with said air bag during the inspiration phase and interrupting the connection between said pressurized air source and the breathing bag during the expiration phase and for actuating a pneumatic adjustment element during the expiration phase for offsetting the force applied by said prestress means.