Respirator having noncircular centroid-mounted exhalation valve
Assignee3M Innovative Properties Company
InventorWilliam A. Mittelstadt
Life of this patent
Estimating the term…
Abstract
A respirator 10 that has a mask body 12 and a harness 16 has an exhalation valve 23 that includes a valve seat 36 and a flexible flap 42. The valve seat 36 has an orifice 38 and has a noncircular seal surface 40 surrounding the orifice 38. The flexible flap 42 is secured to the valve seat 36 at a centroid of the orifice and has a variable stiffness structure. The variable stiffness structure allows the flap to equally deflect under a given load at different distances from the centroid at the noncircular seal surface. An exhalation valve having this construction may beneficially optimize pressure drop and overall valve performance for applications where valve space may be limited.
Claims20
An exhalation valve that comprises:
- (a) a valve seat that has an orifice and that has a noncircular seal surface surrounding the orifice;
- and
- (b) a flexible flap that is secured to the valve seat at a centroid of the orifice and that has a variable stiffness structure comprising a plurality of ribs that extend radially from the centroid of the flexible flap, wherein a first rib of the plurality of ribs comprises a stiffness that is different from a stiffness of a second rib of the plurality of ribs.
A respirator that comprises:
- (a) a harness;
- and
- (b) a mask body that comprises an exhalation valve that includes:
- (i) a valve seat that has an orifice and that has a noncircular seal surface surrounding the orifice;
- and
- (ii) a flexible flap that is secured to the valve seat at a centroid of the orifice and that has a variable stiffness structure comprising a plurality of ribs that extend radially from the centroid of the flexible flap, where a first rib of the plurality of ribs has a cross-sectional area along a length of the first rib that is different from a cross-sectional area of a second rib of the plurality of ribs along a length of the second rib.
Dependencies are inferred from the claim text.