RECIRCULATION TYPE RESPIRATION PROTECTIVE APPARATUS OPERATED UNDER POSITIVE PRESSURE EQUIPPED WITH INHALATION AND EXHALATION DUCTS

摘要

PURPOSE: To secure the capacity of a respiration protecting device during operation preparation by bouncing back a plate due to the elastic intrinsic restoring force to a valve seat by a fork-shaped touching piece attached on a mask connecting part when a mask is removed. CONSTITUTION: A web 10 fixed in a mask connecting part 9 supports a fork- shaped wire bent member 11 and both legs 12 of the wire bent member push a plate 7 in the direction leaving a valve seat 8 into an inner room of a device connecting part 1. When the mask connecting part 9 is removed from the device connecting part 1, fastening of the wire bent member 11 by the fork-shaped leg part is released and, as a result, the plate 7 abuts on the valve seat 8 by the intrinsic elasticity of itself. Thereby the device connecting part 1 is sealed against the atmospheric air and gas in the respiration circuit cannot escapee out despite its positive pressure.