RESPIRATOR PRESSURE-DEMAND EXHALATION VALVE

摘要

RESPIRATOR PRESSURE-DEMAND EXHALATION VALVE A chamber in a valve case has an inlet port for 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 sealing member, the opposite side of which is engaged by a rigid disc secured to a valve stem that extends through the port and into guiding means for the stem. The diameter of the disc is nearly as great as the diameter of the chamber. A spring in the case is compressed between the disc and the other end wall of the valve chamber for pressing the sealing member against the seat. The disc is spaced from the ported wall of the chamber far enough for the marginal portion of the disc that extends laterally out beyond the sealing member to be inclined toward the ported wall but spaced from it. The side wall of the chamber is provided with exhaust slots extending around the disc and having inner walls adjacent the ported wall lying in a plane substantially coinciding with the plane in which lies the edge of the disc, and the space between the valve seat and the side wall of the case is always open to the slots.