Respirator pressure demand exhalation valve - has seal spring biased against valve stem disc and side exhaust slots

摘要

The chamber in the valve case has an inlet port of exhaled air in one of its end walls. Spaced inwardly from the side wall of the chamber is a valve seat surrounding the inlet port and engaged by one side of a seal. The opposite side of the seal is engaged by a rigid disc secured to a valve stem that extends through the port and into a guide for the stem. A spring in the case is compressed between the disc and the other end wall of the valve chamber for pressing the seal against the seat. The disc is spaced from the ported wall of the chamber. The side wall of the chamber is provided with exhaust slots extending around the disc with inner walls adjacent the ported wall. The space between the valve seat and the side wall of the case is always open to the slots.