Vent for soil pipe stack

Claim 2

A filter for a soil pipe vent stack comprising an open ended cylindrical casing adapted to be mounted at the open upper end of a soil pipe vent stack so that the gases escaping from the vent stack are caused to flow upwardly through said casing, said casing having at least two sets of vertically spaced baffles therein, each set of said baffles extending substantially entirely across the cross section of said cylindrical casing and comprising a plurality of spaced apart vanes inclined to the vertical axis of the casing, the uppermost set of said baffles being located substantially below the upper end of said casing and defining the lower end Of a cylindrical chamber at the upper end of said casing and a gas filtering medium in said cylindrical chamber.

Claim 3

A filter as called for in claim 1 including a second open ended cylindrical casing disposed concentrically within said cylindrical chamber, said filter medium being disposed between said first and second casings and substantially filling the space therebetween.

Claim 4

A filter as called for in claim 2 wherein the cross-sectional area of the second cylindrical casing is relatively small in comparison with the cross-sectional area of the first cylindrical casing.

Claim 5

A filter as called for in claim 3 wherein said filter medium comprises a metal woollike material.

Claim 6

A filter as called for in claim 3 wherein the diameter of said second casing is not greater than about one-third the diameter of said first casing.

Claim 7

A filter as called for in claim 5 wherein said second casing extends from the upper set of baffles to adjacent the upper end of the first casing.

Claim 8

A filter as called for in claim 6 wherein said second casing has a length equal to about one-half the length of said first casing.

Claim 9

A filter as called for in claim 3 wherein said first casing is provided with a radially outwardly extending peripheral flange around the upper end thereof, said flange being adapted to engage the upper end of the vent stack when the filter is inserted therein to thereby support the filter within the open upper end of the vent stack.

Claim 10

A filter as called for in claim 8 including a plurality of spring clips on said peripheral flange for frictionally engaging the upper end of the vent stack.

Claim 11

In combination, a soil pipe vent stack having a vertically extending open upper end, a filter connected to said open upper end such that the gases emitted from said vent stack are constrained to flow through said filter, said filter comprising an open ended cylindrical casing having at least two sets of vertically spaced baffles therein, each set of said baffles extending substantially entirely across the cross section of said cylindrical casing and comprising a plurality of spaced apart inclined to the vertical axis of the casing, the uppermost set of said baffles being located substantially below the upper end of said casing and defining the lower end of a cylindrical chamber at the upper end of said casing and a gas filtering medium in said cylindrical chamber.

Claim 12

In combination, a soil pipe vent stack having a vertically extending open upper end, a filter connected to said open upper end such that the gases emitted from said vent stack are constrained to flow through said filter, said filter comprising an open ended cylindrical casing having at least two sets of vertically spaced baffles therein, each set of said baffles extending substantially entirely across the cross section of said cylindrical casing and comprising a plurality of spaced apart inclined to the vertical axis of the casing, the uppermost set of said baffles being located substantially below the upper end of said casing and defining the lower end of a cylindrical chamber at the upper end of said casing and a gas filtering medium in said cylindrical chamber.

Claim 13

The combination called for in claim 10 wherein said cylindrical casing is telescopically arranged within said open upper end of the vent stack and including means at the upper end of the filter for supporting the filter at said open upper end of the filter stack.

Claim 14

The combination called for in claim 11 wherein said last-mentioned means comprises a radially outwardly extending peripheral flange around said cylindrical casing, said peripheral flange having an outer diameter greater than the outer diameter of the vent stack so as to support the filter on the vent stack and to seal the space between the outer periphery of said casing and the inner periphery of the vent stack.

Claim 15

The combination called for in claim 12 including a second open ended cylindrical casing disposed concentrically within said cylindrical chamber, said filter medium being disposed between said first and second casing and substantially filling the space therebetween.

Claim 16

The combination called for in claim 13 wherein said filtering medium comprises a metal woollike material.

Claim 17

The combination called for in claim 14 wherein the diameter of said second casing is not greater than about one-third the diameter of said first casing.