Portable air purge

Claim 2

A portable air purifying filter suitable for personal use comprising a tubular shell which includes two longitudinally matching half-tubes having registering longitudinal offset joints, said joints comprising a longitudinal parallel planar flange on both outer edges of one half tube and planar edge on each outer edge of the second half tube whereby when the edges of both half tubes are assembled and registered with each other, the exterior and interior surfaces of the resulting unitary tube are substantially cylindrical, axially spaced circumferential bands embracing said assembled half tubes to hold the same together in register, a carrying strap attached at its ends to said bands, a screened inlet at one end of the shell and a tangential outlet connected to and positioned adjacent the other end of the shell and a rotary blower with operating motor positioned in the other end of the shell and a filtering medium between the inlet and the said rotary blower.

Claim 3

The portable air purifying filter of claim 1 which further comprises a high efficiency particulate filter and an activated carbon filter in series between the inlet and the rotary blower.

Claim 4

The combination of claim 2 wherein said rotary blower is mounted in the shell co-axially, and said tangential outlet comprises a tangential discharge fitting, rotatable mounted about the axis of the rotary blower for selectively directing the discharge of the blower in various directions.

Claim 5

A filter comprising a substantially cylindrical shell composed of two longitudinally extending semi-cylindrical parts joined by offset longitudinal parallel flanges, the flanges of one part being disposed radially inside and nesting within the flanges on the other part, leaving a smooth cylindrical surface on the inside and on the outside of said shell, a band adjacent each end of said shell embracing said shell and holding said semi-cylindrical parts in circumferential registration with each other, a pre-filter fitting the inlet end of said shell, said pre-filter comprising a screen and a porous fibrous filter sheet extending across said screen, a high efficiency fibrous filter body disposed in said shell and filling the cross-section thereof, a cylindrical body of activated carbon particles disposed in said shell adjacent to but separate from said fibrous filter body by a rigid screen, said screen being attached at its periphery to the inside of the cylindrical shell, a second transverse screen in said cylindrical body resting against the cylindrical body of activated carbon, a compression spring in said cylindrical body engaging the second transverse screen at one end and engaging at the other end the inner periphery of said cylindrical shell to maintain the body of activated carbon under compression and against displacement, and a suction fan having a volute with its inlet communicating with the last said end of the body of activated carbon, said volute being disposed in a plane transverse to the longitudinal axis of the cylindrical shell and having a tangential discharge passage, and a driving motor for said fan said motor being disposed in the end of the shell remote from the inlet end.

Claim 6

A filter comprising a substantially cylindrical shell composed of two longitudinally extending semi-cylindrical parts joined by offset longitudinal parallel flanges, the flanges of one part being disposed radially inside and nesting within the flanges on the other part, leaving a smooth cylindrical surface on the inside and on the outside of said shell, a band adjacent each end of said shell embracing said shell and holding said semi-cylindrical parts in circumferential registration with each other, a pre-filter fitting the inlet end of said shell, said pre-filter comprising a screen and a porous fibrous filter sheet extending across said screen, a high efficiency fibrous filter body disposed in said shell and filling the cross-section thereof, a cylindrical body of activated carbon particles disposed in said shell adjacent to but separate from said fibrous filter body by a rigid screen, said screen being attached at its periphery to the inside of the cylindrical shell, a second transverse screen in said cylindrical body resting against the cylindrical body of activated carbon, a compression spring in said cylindrical body engaging the second transverse screen at one end and engaging at the other end the inner periphery of said cylindrical shell to maintain the body of activated carbon under compression and against displacement, and a suction fan having a volute with its inlet communicating with the last said end of the body of activated carbon, said volute being disposed in a plane transverse to the longitudinal axis of the cylindrical shell and having a tangential discharge passage, and a driving motor for said fan said motor being disposed in the end of the shell remote from the inlet end.