Ambient air breathing device

摘要

An automatically closing ambient air device is disclosed having a generally conical passageway, containing an inlet for the flow of fluid from the ambient environment into the passageway and an outlet for the flow of such fluid from the passageway, and having valve means arranged to close fluid flow through the outlet from the passageway which is actuated by buoyant force and/or gravitational force and/or a combination thereof imposed by a weighted element in response to the spacial orientation of the conical wall of the passageway to level.