Gas separating and venting filter

Claim 2

A gas separating and venting filter that is capable of separating gases and liquids and of venting the gases in any position of the filter, comprising: a housing having walls defining an interior chamber, with inlet means in the housing for the flow of liquid into said chamber, and outlet means in the housing downstream of said inlet means for the flow of liquid out of said chamber; hydrophilic filter means between said inlet means and said outlet means for passing liquid only therethrough; hydrophobic filter means along substantially the entire length of one wall of said chamber between said inlet means and said outlet means and upstream of said hydrophilic filter means for passing gas but-not liquid therethrough; and vent means for venting gas which has passed through said hydrophobic filter means.

Claim 3

The filter of claim 1 wherein said vent means comprises a plurality of spaced vent holes through said one wall of the chamber.

Claim 4

The filter of claim 1 wherein said hydrophilic filter means is disposed along substantially the entire length of a'second wall of said chamber opposite said one wall, with passage means in said second wall leading to said outlet means.

Claim 5

The filter of claim 3 wherein said hydrophilic filter means is heat sealed to said second wall about said passage means.

Claim 6

The filter of claim 4 wherein said hydrophilic filter means comprises a continuous plastic filter membrane.

Claim 7

The filter of claim 5 wherein said membrane is ultrasonic welded to said second wall about the periphery of the membrane.

Claim 8

The filter of claim 1 wherein said hydrophobic filter means is heat sealed to said second wall.about said passage means.

Claim 9

The filter of claim 7 wherein said hydrophobic filter means comprises a continuous plastic liquid-repellant filter membrane.

Claim 10

The filter of claim 8 wherein said membrane 'is ultrasonic welded to said second wall about the periphery of the membrane.

Claim 11

A gas separating and venting filter that is capable of separating gases and liquids and of venting the gases from the filter, comprising: a housing having walls defining an interior chamber, with inlet means in the housing for the flow of liquid into said chamber, and outlet means in the housing downstream of said inlet means for the flow of liquid out of said chamber; hydrophobic filter means adjacent one wall of said chamber between said inlet means and said outlet means for passing gas but not liquid therethrough, with vent means for venting gas which has passed through said hydrophobic filter means; a flexible hydrophilic filter membrane along a second wall of said chamber for passing liquid only therethrough; and at least one passageway in said second wall extending along said filter membrane and leading toward said outlet means, said passageway having open sides along its length facing said membrane, and the passageway having a depth within the elastic limits of said flexible membrane, whereby the flexible membrane balloons into the passageway in response to a buildup of pressure in said chamber to restrict the flow of liquid through the passageway, until the membrane ultimately engages the opposite side of the passageway under extreme pressure to completely shut off the flow of liquid to said outlet means.

Claim 12

A gas separating and venting filter that is capable of separating gases and liquids and of venting the gases from the filter, comprising: a housing having walls defining an interior chamber, with inlet means in the housing for the flow of liquid into said chamber, and outlet means in the housing downstream of said inlet means for the flow of liquid out of said chamber; hydrophobic filter means adjacent one wall of said chamber between said inlet means and said outlet means for passing gas but not liquid therethrough, with vent means for venting gas which has passed through said hydrophobic filter means; a flexible hydrophilic filter membrane along a second wall of said chamber for passing liquid only therethrough; and at least one passageway in said second wall extending along said filter membrane and leading toward said outlet means, said passageway having open sides along its length facing said membrane, and the passageway having a depth within the elastic limits of said flexible membrane, whereby the flexible membrane balloons into the passageway in response to a buildup of pressure in said chamber to restrict the flow of liquid through the passageway, until the membrane ultimately engages the opposite side of the passageway under extreme pressure to completely shut off the flow of liquid to said outlet means.

Claim 13

The filter of claim 10 wherein said passageway has a concave cross-section generally perpendicular to the plane of said membrane.

Claim 14

The filter of claim 11 wherein said cross-section is that of a smooth longitudinal section of a cylinder.

Claim 15

The filter of claim. 10 wherein said membrane is heat sealed to said second wall about said passageway.

Claim 16

The filter of claim 3 wherein said membrane is ultrasonic welded to said second.wall about the periphery of the membrane.

Claim 17

The filter of claim 10 including a plurality of said open-sided passageways extending generally. parallel to each other and parallel to said membrane along said second wall.

Claim 18

The filter of claim 15 wherein said passageways comprise longitudinal cylindrical sections presenting smooth concave surfaces facing said membrane.

Claim 19

The filter of claim 16 wherein said passageways comprise longitudinal cylindrical sections of less than 1 80 0 , with the longitudinal edges of each passageway defining a mutual juncture with the adjacent passageway.

Claim 20

A gas separating and venting filter that is capable of separating gases and liquids and of venting the gases in any position of the filter, comprising: a housing having an interior chamber defined in part by a pair of longitudinally extending, opposed. major walls joined by opposite end walls, with inlet means in one of the end walls for the flow of liquid into said chamber, and outlet means in the opposite end wall downstream of the inlet means for the flow of liquid out of the chamber; hydrophilic filter means in the form of a continuous plastic filter membrane extending along one of said major walls, with passage means in said one major wall leading to said outlet means; hydrophobic filter means in the form of a continuous plastic liquid-repellant filter membrane extending along substantially the entire length of the second major wall of said chamber between said inlet means and said outlet means for passing gas but not liquid therethrough; a plurality of spaced vent holes through said second major wall of the chamber for venting gas which has passed through said hydrophobic filter membrane; said hydrophilic filter membrane being sealed about the periphery thereof to said first major wall; and said hydrophobic filter membrane being sealed about the periphery thereof to said second major wall.

Claim 21

A gas separating and venting filter that is capable of separating gases and liquids and of venting the gases in any position of the filter, comprising: a housing having an interior chamber defined in part by a pair of longitudinally extending, opposed. major walls joined by opposite end walls, with inlet means in one of the end walls for the flow of liquid into said chamber, and outlet means in the opposite end wall downstream of the inlet means for the flow of liquid out of the chamber; hydrophilic filter means in the form of a continuous plastic filter membrane extending along one of said major walls, with passage means in said one major wall leading to said outlet means; hydrophobic filter means in the form of a continuous plastic liquid-repellant filter membrane extending along substantially the entire length of the second major wall of said chamber between said inlet means and said outlet means for passing gas but not liquid therethrough; a plurality of spaced vent holes through said second major wall of the chamber for venting gas which has passed through said hydrophobic filter membrane; said hydrophilic filter membrane being sealed about the periphery thereof to said first major wall; and said hydrophobic filter membrane being sealed about the periphery thereof to said second major wall.

Claim 22

The filter of claim 18 wherein said hydrophilic and hydrophobic filter membranes are plastic and are ultrasonic welded to said first and second major walls, respectively, about the peripheries of the membranes.

Claim 23

The filter of claim 18 wherein said passage "means comprises a plurality of open-sided passageways in said first major wall extending generally parallel to each other and parallel to and facing said hydrophilic membrane along substantially the entire length of said first major wall.

Claim 24

A gas separating and venting filter that is capable of separating gases and liquids and of venting the gases from the filter, comprising: a molded plastic housing having a first part defining a longitudinally extending open-sided recess defined by a first longitudinally extending major wall and opposite end walls, with inlet means in one end wall for the flow of liquid into said housing and outlet means in the opposite end wall downstream of the inlet means for the flow of liquid out of said housing, and passage means in said first major wall leading to said outlet means; a hydrophilic plastic filter membrane sealed to said first major wall about said passage means; said housing including a second part sealed to said first part and defining a cap for closing the recess in said first part to define an interior chamber within said housing; a hydrophobic filter membrane along substantially the entire length of said second part on the interior thereof between said inlet means and said outlet means for passing gas but not liquid therethrough; and vent means through said second part for venting gas which has passed through said hydrophobic filter membrane.

Claim 25

A gas separating and venting filter that is capable of separating gases and liquids and of venting the gases from the filter, comprising: a molded plastic housing having a first part defining a longitudinally extending open-sided recess defined by a first longitudinally extending major wall and opposite end walls, with inlet means in one end wall for the flow of liquid into said housing and outlet means in the opposite end wall downstream of the inlet means for the flow of liquid out of said housing, and passage means in said first major wall leading to said outlet means; a hydrophilic plastic filter membrane sealed to said first major wall about said passage means; said housing including a second part sealed to said first part and defining a cap for closing the recess in said first part to define an interior chamber within said housing; a hydrophobic filter membrane along substantially the entire length of said second part on the interior thereof between said inlet means and said outlet means for passing gas but not liquid therethrough; and vent means through said second part for venting gas which has passed through said hydrophobic filter membrane.

Claim 26

The filter of claim 21 wherein said hydrophilic and hydrophobic filter membranes are plastic and are ultrasonic welded to said first and second major walls, respectively, about said passage means and said vent means, respectively.

Claim 29

The method of claim 23 wherein said filter membrane is plastic and including the step of ultrasonic welding the membrane to the housing about said vent means.

Claim 30

A gas separating and venting filter that is capable of separating gases and liquids and of venting the gases from the filter, comprising: a housing having walls defining an interior chamber, with inlet means in the housing for the flow of liquid into said chamber, and outlet means in the . housing downstream of said inlet means for the flow of liquid out of said chamber; hydrophobic filter means adjacent one wall of said chamber between said inlet means and said outlet means'for passing gas but not liquid therethrough, with vent means for venting gas which has passed through said hydrophobic filter means; a flexible hydrophilic filter membrane along a second wall of said chamber for passing liquid only therethrough; and a plurality of open-sided passageways in said second wall extending generally parallel to each other and parallel to and facing said filter membrane and leading toward said outlet means, each of said passageways comprising a longitudinal cylindrical section of less than 180 0 presenting a smooth concave surface facing said membrane, the composite depth of said passageways being within the elastic limits of said flexible membrane, whereby the flexible membrane balloons into the passageways in response to a build- up of pressure in said chamber to restrict the flow of liquid through the passageways, until the membrane ultimately engages the concave sides of the passageways under extreme pressure to completely shut off the flow of liquid to said outlet means.

Claim 31

A gas separating and venting filter that is capable of separating gases and liquids and of venting the gases from the filter, comprising: a housing having walls defining an interior chamber, with inlet means in the housing for the flow of liquid into said chamber, and outlet means in the . housing downstream of said inlet means for the flow of liquid out of said chamber; hydrophobic filter means adjacent one wall of said chamber between said inlet means and said outlet means'for passing gas but not liquid therethrough, with vent means for venting gas which has passed through said hydrophobic filter means; a flexible hydrophilic filter membrane along a second wall of said chamber for passing liquid only therethrough; and a plurality of open-sided passageways in said second wall extending generally parallel to each other and parallel to and facing said filter membrane and leading toward said outlet means, each of said passageways comprising a longitudinal cylindrical section of less than 180 0 presenting a smooth concave surface facing said membrane, the composite depth of said passageways being within the elastic limits of said flexible membrane, whereby the flexible membrane balloons into the passageways in response to a build- up of pressure in said chamber to restrict the flow of liquid through the passageways, until the membrane ultimately engages the concave sides of the passageways under extreme pressure to completely shut off the flow of liquid to said outlet means.

Claim 32

A liquid filter, comprising: a housing having a filter chamber with a flexible hydrophilic filter membrane in the chamber such that the membrane is capable of flexing in response to variations in the fluid pressure within the chamber, and means operatively associated with the membrane for automatically restricting the flow of liquid through the filter in response to an increase of said fluid pressure.

Claim 33

A liquid filter, comprising: a housing having a filter chamber with a flexible hydrophilic filter membrane in the chamber such that the membrane is capable of flexing in response to variations in the fluid pressure within the chamber, and means operatively associated with the membrane for automatically restricting the flow of liquid through the filter in response to an increase of said fluid pressure.

Claim 34

The filter of claim 26 wherein said last named means includes means for completely shutting off the flow of liquid in response to an extreme pressure.