Patent ID: 7578293

Claim:
A compressed air respirator apparatus, comprising: a compressed air reserve with a connected demand air supply valve; a reversible breathing gas reservoir with an adjustable volume, said demand air supply valve being connected with said reversible breathing gas reservoir to supply said reversible breathing gas reservoir with air; a rebreathing line with a user connection for the user of the apparatus, said rebreathing line having an expiration valve for expiring exhaled breathing air from said rebreathing line to the respirator environment when gas pressure in said breathing line is above a preset pressure, said rebreathing line being in bi-directional flow connection with gas in said breathing gas reservoir such that gas pressure in said reversible breathing gas reservoir is the same as said gas pressure in said breathing line; a motor operatively connected to said reversible breathing gas reservoir to change the volume thereof; a motor control wherein the volume of said breathing gas reservoir is set by means of said motor controlled by said motor control; a control unit; and a combined sensor for CO 2 concentration and breathing gas volume flow, said combined sensor being arranged in said rebreathing line, said combined sensor being connected with said control unit and said motor control such that depending on a breath-resolved O 2 volume flow determined by means of said combined sensor, the volume for rebreathing from said breathing gas reservoir is regulated by means of said motor control such that a CO 2 concentration level stored in said control unit is obtained, on average, for rebreathing.