High efficiency respirator
First Claim
Patent Images
1. An expanded area filtration face mask adapted to cover the mouth and nose of a wearer of the mask comprising:
- a filter member including at least one layer of filter material, said filter member having,a shape-retaining annular base adapted to fit confomingly against the face of a wearer of the mask and tending to hold said filter member in the opened position;
at least two sidewall portions generally extending away from said annular base;
a frontal portion bridging said sidewall portions; and
at least two supporting arch structures disposed at the junction of said sidewall and frontal portions, and intersecting said annular base;
the interior surface area of said filter member defined by said sidewall and frontal portions being greater than that of the segment of a sphere defined by a plane having the same area as enclosed by said annular base and a height equal to that of the interior of the filter member, whereby the pressure drop through said filter member is no more than 40 mm H2 O at a flow rate of 85 liters/minute;
said filter member being constituted such that upon removal of said annular base, said sidewall portion can be folded along with supporting arch, in face-to-face contact with said frontal portion to form a flat structure having an at least partially curved perimeter.
1 Assignment
0 Petitions
Accused Products
Abstract
The invention provides a filtration face mask which has an expanded filtration surface area and high filter efficiency. The mask includes at least two sidewall portions generally extending away from the face of the wearer and away from an annular base. A frontal portion bridges the sidewall portions and at least two supporting arche structures are disposed at the junction of the sidewall and frontal portions.
-
Citations
32 Claims
-
1. An expanded area filtration face mask adapted to cover the mouth and nose of a wearer of the mask comprising:
-
a filter member including at least one layer of filter material, said filter member having, a shape-retaining annular base adapted to fit confomingly against the face of a wearer of the mask and tending to hold said filter member in the opened position; at least two sidewall portions generally extending away from said annular base; a frontal portion bridging said sidewall portions; and at least two supporting arch structures disposed at the junction of said sidewall and frontal portions, and intersecting said annular base; the interior surface area of said filter member defined by said sidewall and frontal portions being greater than that of the segment of a sphere defined by a plane having the same area as enclosed by said annular base and a height equal to that of the interior of the filter member, whereby the pressure drop through said filter member is no more than 40 mm H2 O at a flow rate of 85 liters/minute; said filter member being constituted such that upon removal of said annular base, said sidewall portion can be folded along with supporting arch, in face-to-face contact with said frontal portion to form a flat structure having an at least partially curved perimeter. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. An expanded area filtration face mask adapted to cover the mouth and nose of a wearer of the mask comprising:
-
a filter member including at least one layer of filter material in sufficient thickness that the mask allows no more than about a 3% penetration of a 0.3 micrometer DOP at a flow rate of 85 liters/minute, said filter member having, a shape-retaining annular base adapted to fit conformingly against the face of a wearer of the mask and tending to hold said filter member in an open position; at least two sidewall portions generally extending away from said annular base; a frontal portion bridging said sidewall portions; and at least two supporting arch structures disposed at the junction of said sidewall and frontal portions, and intersecting said annular base; the interior surface area of the filter member defined by said sidewall and frontal portions being greater than that of the segment of a sphere defined by a plane having the same area as enclosed by said annular base and a height equal to that of the interior of the filter member, whereby the pressure drop through the filter member is not more than 40 mm H2 O at a flow rate of 85 liters/minute. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32)
-
-
18. The mask of claim 18 wherein said mask allows no more than a 0.1% penetration of 0.3 micrometer DOP particles at a flow rate of 85 liters/minute.
Specification