[A rotative control plate for separation of inspired and expired gases (author's transl)]

Some drawbacks of the valve chamber are well known: high flow gas resistance, sensitivity to position and to condensation of water vapour, vibrations of the valve especially at high flow rate. To avoid these defects a rotative control valve separating inhaled and exhaled gases is described. A rotative plate shuts off one of two large ports and separates expired and inspired gases. The rotation of the plate is controlled by a sensor signal, which may be delivered by a pneumotachograph and switches on and off the electrical supply of the motor. The major characteristics of this valve are: its small dead space (11 cm3), a negligible error in the volumes which are to be displaced through either of the two ports, a total insensitivity to water condensation, a very low flow resistance and an insensitivity to position and displacement. This device may be adapted to infants and neonates.