Evaporation loss control

Claim 2

A canister for use in a system for controlling loss of fuel vapor from a vehicle having a fuel reservoir and an internal combustion engine with an induction passage, said canister comprising means forming a generally cylindrical side wall and a pair of oppositely disposed end walls which define a chamber therewithin, one of said end walls having a central portion and an outer annular portion with said central portion disposed closer to the other of said end walls than said outer portion and connected to said outer portion by a generally cylindrical portion, a quantity of fuel vapor adsorbing material filling said chamber, fuel vapor inlet means connected to said central portion and adapted for connection to said reservoir whereby fuel vapor emitted from said reservoir may be dispersed into said adsorbing material from a mid-portion thereof, and fuel vapor outlet means connected to said outer portion and adapted for connection to said induction passage whereby fuel vapor may be purged from said adsorbing material to said induction passage through an area surrounding said midportion and axially removed therefrom.

Claim 3

The canister of claim 1 which further comprises additional fuel vapor outlet means connected to said central portion and adapted For connection to said induction passage whereby fuel vapor also may be purged from said mid-portion of said adsorbing material to said induction passage and directly from said reservoir to said induction passage.

Claim 4

The canister of claim 1 wherein said end walls are molded from a plastic material and comprise grids permitting fluid flow to and from said adsorbing material but preventing loss of said adsorbing material form said chamber.

Claim 5

The canister of claim 3 which further comprises filter means overlying said grids for preventing entrance of dust to said chamber and loss of said adsorbing material from said chamber.

Claim 6

A canister for use in a system for controlling loss of fuel vapor from a vehicle having a fuel reservoir and an internal combustion engine with an induction passage, said canister comprising a molded plastic body member having a generally cylindrical side wall with a vertical axis, an annular end wall intersecting said side wall at its upper end and extending inwardly therefrom, said end wall being molded in a grid defining a plurality of apertures extending therethrough, said end wall having an upwardly extending sealing lip circumscribing said grid, an upwardly opening generally frusto-conical inner wall disposed concentrically about said axis and intersecting said end wall and extending upwardly and downwardly therefrom, and an inner grid disposed at the lower end of said inner wall, said inner grid defining a plurality of apertures extending therethrough, a quantity of fuel vapor adsorbing material contained in the portion of said body member immediately below said annular end wall grid and said inner grid and surrounding the portion of said inner wall below said end wall, and a molded plastic cover member secured over said body member and engaging said sealing lip and said inner wall to define an annular chamber above said annular end wall grid and an inner chamber above said inner grid, said cover member having an inlet fitting opening to said inner chamber and adapted for connection to said fuel reservoir and a purge fitting opening from said annular chamber and adapted for connection to said induction system whereby fuel vapor emitted from said reservoir may be dispersed into said adsorbing material from a mid-portion thereof and whereby fuel vapor may be purged from said adsorbing material to said induction system through an area surrounding said midportion and axially removed therefrom.

Claim 7

A canister for use in a system for controlling loss of fuel vapor from a vehicle having a fuel reservoir and an internal combustion engine with an induction passage, said canister comprising a molded plastic body member having a generally cylindrical side wall with a vertical axis, an annular end wall intersecting said side wall at its upper end and extending inwardly therefrom, said end wall being molded in a grid defining a plurality of apertures extending therethrough, said end wall having an upwardly extending sealing lip circumscribing said grid, an upwardly opening generally frusto-conical inner wall disposed concentrically about said axis and intersecting said end wall and extending upwardly and downwardly therefrom, and an inner grid disposed at the lower end of said inner wall, said inner grid defining a plurality of apertures extending therethrough, a quantity of fuel vapor adsorbing material contained in the portion of said body member immediately below said annular end wall grid and said inner grid and surrounding the portion of said inner wall below said end wall, and a molded plastic cover member secured over said body member and engaging said sealing lip and said inner wall to define an annular chamber above said annular end wall grid and an inner chamber above said inner grid, said cover member having an inlet fitting opening to said inner chamber and adapted for connection to said fuel reservoir and a purge fitting opening from said annular chamber and adapted for connection to said induction system whereby fuel vapor emitted from said reservoir may be dispersed into said adsorbing material from a mid-portion thereof and whereby fuel vapor may be purged from said adsorbing material to said induction system through an area surrounding said midportion and axially removed therefrom.

Claim 8

The canister of claim 5 wherein said body member and said cover member are molded from heat stabilized nylon.

Claim 9

The canister of claim 5 wherein said annular end wall grid is formed by a plurality of flat ribs extending radially from said inner wall to said sealing lip and spaced circumferentially about said inner wall, a plurality of undulating ribs also extending radially from said inner wall to said sealing lip between said flat ribs and having a circumferential dimension substantially equal to the circumferential spacing between said flat ribs, said undulating ribs having peak portions disposed at the same height as said flat ribs and valley portions disposed lower than said flat ribs, and a plurality of circular ribs spaced between said inner wall and said sealing lip and interconnecting said peak portions of said undulating ribs with said flat ribs, whereby said apertures extending through said end wall grid are defined to open horizontally from spaces above said valley portions and between said circular ribs to spaces below said flat ribs and between said circular ribs.

Claim 10

The canister of claim 5 wherein said inner wall grid is defined by a plurality of spaced parallel flat ribs, a plurality of parallel undulating ribs disposed between said flat ribs and having a width substantially equal to the spacing between said flat ribs, said undulating ribs having peak portions disposed at the same height as said flat ribs and valley portions disposed lower than said flat ribs, and a plurality of cross ribs extending perpendicular to said flat and undulating ribs and interconnecting said peak portions of said undulating ribs with said flat ribs, whereby said apertures extending through said inner wall grid are defined to open horizontally from spaces above said valley portions and between said cross ribs to spaces below said flat ribs and between said cross ribs.

Claim 11

A canister for use in a system for controlling loss of fuel vapor from a fuel reservoir, said canister comprising means forming a generally cylindrical side wall and an end wall which define a chamber open at one end, fuel vapor inlet means opening into said chamber and adapted for connection to said reservoir whereby fuel vapor emitted from said reservoir may be conducted to said chamber, a quantity of fuel vapor adsorbing material disposed within said chamber, means forming a closure disposed adjacent said open end of said chamber and having its circumference slidably engaging said side wall, and spring means biasing said closure forming means toward said end wall whereby said adsorbing material is retained in a tightly packed manner therebetween.

Claim 12

A canister for use in a system for controlling loss of fuel vapor from a fuel reservoir, said canister comprising means forming a generally cylindrical side wall and an end wall which define a chamber open at one end, fuel vapor inlet means opening into said chamber and adapted for connection to said reservoir whereby fuel vapor emitted from said reservoir may be conducted to said chamber, a quantity of fuel vapor adsorbing material disposed within said chamber, means forming a closure disposed adjacent said open end of said chamber and having its circumference slidably engaging said side wall, and spring means biasing said closure forming means toward said end wall whereby said adsorbing material is retained in a tightly packed manner therebetween.

Claim 13

The canister of claim 9 which further comprises an annular spring seat portion extending inwardly from said side wall at said open end of said chamber and overlapping said circumference of said closure forming means, and wherein said spring means comprises a wave spring disposed between said spring seat portion and said closure forming means.

Claim 14

A canister for use in a system for controlling loss of fuel vapor from a fuel reservoir, said canister comprising means forming a generally cylindrical side wall and an end wall which define a chamber open at one end, fuel vapor inlet means opening into said chamber and adapted for connection to said reservoir whereby fuel vapor emitted from said reservoir may be conducted to said chamber, a quantity of fuel vapor adsorbing material disposed within said chamber, means forming a closure disposed adjacent said open end of said chamber, and compressed polyurethane pads disposed between said adsorbing material and said end wall and said closure to retain said adsorbing material in a tightly packed manner therebetween.

Claim 15

A canister for use in a system for controlling loss of fuel vapor from a fuel reservoir, said canister comprising means forming a generally cylindrical side wall and an end wall which define a chamber open at one end, fuel vapor inlet means opening into said chamber and adapted for connection to said reservoir whereby fuel vapor emitted from said reservoir may be conducted to said chamber, a quantity of fuel vapor adsorbing material disposed within said chamber, means forming a closure disposed adjacent said open end of said chamber, and compressed polyurethane pads disposed between said adsorbing material and said end wall and said closure to retain said adsorbing material in a tightly packed manner therebetween.

Claim 16

A canister for use in a system for controlling loss of fuel vapor from a vehicle having a fuel reservoir and an internal combustion engine with an induction passage, said canister comprising a molded plastic body member having a generally cylindrical side wall with a vertical axis, an annular end wall intersecting said side wall at its upper end and extending inwardly therefrom, said end wall being molded in a grid defining a plurality of apertures extending therethrough, said end wall having an upwardly extending sealing lip circumscribing said grid, an upwardly opening generally frusto-conical inner wall disposed concentrically about said axis and intersecting said end wall and extending upwardly and downwardly therefrom, and an inner grid disposed at the lower end of said inner wall, said inner grid defining a plurality of apertures extending therethrough, an annular polyurethane filter pad overlying said annular end wall grid, an inner polyurethane filter pad overlying said inner grid, a molded plastic cover member secured over said body member and engaging said sealing lip and said inner wall to define an annular chamber containing said annular filter pad and an inner chamber containing said inner filter pad, said cover member having an inlet fitting opening to said inner chamber and adapted for connection to said fuel reservoir and a purge fitting opening from said annular chamber and adapted for connection to said induction system, a quantity of fuel vapor adsorbing material contained in the portion of said body member immediately below said annular end wall grid and said inner grid and surrounding the portion of said inner wall below said end wall, a fine mesh nylon screen underlying said adsoRbing material, a molded plastic lower wall member underlying and supporting said screen and said adsorbing material, said lower wall member being molded in a grid defining a plurality of apertures therethrough, said lower wall member having a depending skirt biased into engagement with said side wall, a lower filter pad underlying said lower wall member grid, a molded plastic base member secured to the lower end of said side wall, said base member having an annular shoulder extending inwardly from said side wall and defining a central opening and having a bar extending diametrically across said opening to divide said opening into two portions, said shoulder and said bar supporting said lower filter pad, and a wave spring member supported on said shoulder and biasing said lower wall member upwardly against said adsorbing material to retain said material in a tightly packed condition.

Claim 17

A canister for use in a system for controlling loss of fuel vapor from a vehicle having a fuel reservoir and an internal combustion engine with an induction passage, said canister comprising a molded plastic body member having a generally cylindrical side wall with a vertical axis, an annular end wall intersecting said side wall at its upper end and extending inwardly therefrom, said end wall being molded in a grid defining a plurality of apertures extending therethrough, said end wall having an upwardly extending sealing lip circumscribing said grid, an upwardly opening generally frusto-conical inner wall disposed concentrically about said axis and intersecting said end wall and extending upwardly and downwardly therefrom, and an inner grid disposed at the lower end of said inner wall, said inner grid defining a plurality of apertures extending therethrough, an annular polyurethane filter pad overlying said annular end wall grid, an inner polyurethane filter pad overlying said inner grid, a molded plastic cover member secured over said body member and engaging said sealing lip and said inner wall to define an annular chamber containing said annular filter pad and an inner chamber containing said inner filter pad, said cover member having an inlet fitting opening to said inner chamber and adapted for connection to said fuel reservoir and a purge fitting opening from said annular chamber and adapted for connection to said induction system, a quantity of fuel vapor adsorbing material contained in the portion of said body member immediately below said annular end wall grid and said inner grid and surrounding the portion of said inner wall below said end wall, a fine mesh nylon screen underlying said adsoRbing material, a molded plastic lower wall member underlying and supporting said screen and said adsorbing material, said lower wall member being molded in a grid defining a plurality of apertures therethrough, said lower wall member having a depending skirt biased into engagement with said side wall, a lower filter pad underlying said lower wall member grid, a molded plastic base member secured to the lower end of said side wall, said base member having an annular shoulder extending inwardly from said side wall and defining a central opening and having a bar extending diametrically across said opening to divide said opening into two portions, said shoulder and said bar supporting said lower filter pad, and a wave spring member supported on said shoulder and biasing said lower wall member upwardly against said adsorbing material to retain said material in a tightly packed condition.

Claim 18

A canister for use in a system for controlling loss of fuel vapor from a vehicle having a fuel reservoir and an internal combustion engine with an induction passage, said canister comprising a molded plastic body member having a generally cylindrical side wall with a vertical axis, an annular end wall intersecting said side wall at its upper end and extending inwardly therefrom, said end wall being molded in a grid defining a plurality of apertures extending therethrough, said end wall having an upwardly extending sealing lip circumscribing said grid, an upwardly opening generally frusto-conical inner wall disposed concentrically about said axis and intersecting said end wall and extending upwardly and downwardly therefrom, and an inner grid disposed at the lower end of said inner wall, said inner grid defining a plurality of apertures extending therethrough, a molded plastic cover member secured over said body member and engaging said sealing lip and said inner wall to define an annular chamber above said annular end wall grid and an inner chamber above said inner grid, said cover member having an inlet fitting opening to said inner chamber and adapted for connection to said fuel reservoir and a purge fitting opening from said annular chamber and adapted fro connection to said induction system, a quantity of fuel vapor adsorbing material contained in the portion of said body member below said annular end wall grid and said inner grid and surrounding the portion of said inner wall below said end wall, a molded plastic lower wall member underlying and supporting said adsorbing material, said lower wall member secured to said side wall and being molded in a grid defining a plurality of apertures therethrough, a compressed annular polyurethane filter pad disposed between said annular end wall grid and said adsorbing material, a compressed inner polyurethane filter pad disposed between said inner grid and said adsorbing material, a compressed lower polyurethane pad disposed between said adsorbing material and said lower wall member, the compression of said polyurethane pads retaining said adsorbing material in a tightly packed manner, an air filter pad underlying said lower wall member grid, and a molded plastic base member secured to the lower end of said side wall, said base member having an annular shoulder extending inwardly from said side wall and defining a central opening and having a bar extending diametrically across said opening to divide said opening into two portions, said shoulder and said bar supporting said air filter pad.

Claim 19

A canister for use in a system for controlling loss of fuel vapor from a vehicle having a fuel reservoir and an internal combustion engine with an induction passage, said canister comprising a molded plastic body member having a generally cylindrical side wall with a vertical axis, an annular end wall intersecting said side wall at its upper end and extending inwardly therefrom, said end wall being molded in a grid defining a plurality of apertures extending therethrough, said end wall having an upwardly extending sealing lip circumscribing said grid, an upwardly opening generally frusto-conical inner wall disposed concentrically about said axis and intersecting said end wall and extending upwardly and downwardly therefrom, and an inner grid disposed at the lower end of said inner wall, said inner grid defining a plurality of apertures extending therethrough, a molded plastic cover member secured over said body member and engaging said sealing lip and said inner wall to define an annular chamber above said annular end wall grid and an inner chamber above said inner grid, said cover member having an inlet fitting opening to said inner chamber and adapted for connection to said fuel reservoir and a purge fitting opening from said annular chamber and adapted fro connection to said induction system, a quantity of fuel vapor adsorbing material contained in the portion of said body member below said annular end wall grid and said inner grid and surrounding the portion of said inner wall below said end wall, a molded plastic lower wall member underlying and supporting said adsorbing material, said lower wall member secured to said side wall and being molded in a grid defining a plurality of apertures therethrough, a compressed annular polyurethane filter pad disposed between said annular end wall grid and said adsorbing material, a compressed inner polyurethane filter pad disposed between said inner grid and said adsorbing material, a compressed lower polyurethane pad disposed between said adsorbing material and said lower wall member, the compression of said polyurethane pads retaining said adsorbing material in a tightly packed manner, an air filter pad underlying said lower wall member grid, and a molded plastic base member secured to the lower end of said side wall, said base member having an annular shoulder extending inwardly from said side wall and defining a central opening and having a bar extending diametrically across said opening to divide said opening into two portions, said shoulder and said bar supporting said air filter pad.