Parallel membranous layer type fluid diffusion cell

Claim 2

A fluid diffusion cell, including a selectively permeable diffusion membrane, folded to form laminae defining alternately positioned first and second sets of pockets, the first set of pockets opening at the opposite side of the membrane to the second set of pockets, the improvement comprising first fluid inlet means and first fluid outlet means in communication with the first set of pockets and located at the mouths thereof, and second fluid inlet means and second fluid outlet means in communication with the second set of pockets and located at the mouths thereof, each inlet and outlet means having an enlarged external chamber, open to the mouths of each pocket of a set, to provide flow paths to each pocket of approximately equal length, a medial member between each inlet and outlet means pressing against the mouths of said pockets to force fluid to flow into and through said pockets while passing from each inlet to each outlet means, the first and second sets of pockets defining separate parallel flow paths for respective fluids, and a support member disposed in each of said pockets for holding adjacent laminae apart from each other and for providing flow paths of predetermined thickness, the length of said flow paths in the pockets being greater than the dimension of said fluid diffusion cell which is perpendicular to said laminae.

Claim 3

The diffusion cell of claim 1 in which said support members in the pockets comprise screens made of a mesh of crossing strands.

Claim 4

The fluid diffusion cell of claim 1 in which said diffusion membrane comprises a mesh over which is applied a thin cover of silicone rubber sufficient to fill the spaces of said mesh.

Claim 5

The diffusion cell of claim 3 in which said support members in the pockets comprise screens made of a mesh of crossing strands.

Claim 6

The fluid diffusion cell of claim 4 in which end portions of the fluid diffusion cell are sealed with an elastomeric sealant.

Claim 7

The fluid diffusion cell of claim 5 in which one of said sets of pockets receives blood while the other of said sets of pockets receives oxygen.

Claim 8

A fluid diffusion cell including a selectively permeable diffusion membrane, folded to form laminae defining alternately positioned first and second sets of pockets, the first set of pockets opening at the opposite side of the membrane to the second set of pockets, manifold means in communication with the first and second sets of pockets and located at the mouths tHereof to feed and withdraw fluid in a flow path through said pockets, and support members disposed in each of said pockets for holding adjacent laminae apart from each other and for providing flow paths of predetermined thickness, the support members in the pockets of said first set extending the entire length of said pockets, while the support members in the pockets of the second set terminate short of the ends of said pockets, whereby unobstructed channels are defined in the ends of the pockets of the second set.

Claim 9

A fluid diffusion cell including a selectively permeable diffusion membrane, folded to form laminae defining alternately positioned first and second sets of pockets, the first set of pockets opening at the opposite side of the membrane to the second set of pockets, manifold means in communication with the first and second sets of pockets and located at the mouths tHereof to feed and withdraw fluid in a flow path through said pockets, and support members disposed in each of said pockets for holding adjacent laminae apart from each other and for providing flow paths of predetermined thickness, the support members in the pockets of said first set extending the entire length of said pockets, while the support members in the pockets of the second set terminate short of the ends of said pockets, whereby unobstructed channels are defined in the ends of the pockets of the second set.

Claim 10

A combination according to claim 7 in which each support member in the pockets of one set is of substantially uniform thickness and has opposite faces in contact with adjoining laminae, and each support member in the pockets of said other set has an enlarged medial section and opposed smaller end sections, said medial section and smaller end sections having opposite faces in contact with adjoining laminae for forming said channels.

Claim 11

A blood oxygenator including a selectively permeable diffusion membrane, folded to form laminae defining alternately positioned first and second sets of pockets, the first set of pockets opening at the opposite side of the membrane to the second set of pockets, manifold means in communication with the mouths of each of the first and second sets of pockets to feed and withdraw blood and oxygen in separate flow paths, each through a separate set of pockets, and a support member disposed in each of said pockets for holding adjacent laminae apart from each other and for providing flow paths of predetermined thickness, in which portions of said support members adjacent the ends thereof are of reduced aggregate thickness, to provide a portion of said blood flow path of increased thickness in contact with said membrane and oxygen flow path, whereby blood flowing through said blood flow path portion of increased thickness is conditioned for relatively increased carbon dioxide diffusion through said membrane, while along the portions of said support members remote from the ends thereof, blood is conditioned for relatively increased oxygen diffusion through said membrane.

Claim 12

A blood oxygenator including a selectively permeable diffusion membrane, folded to form laminae defining alternately positioned first and second sets of pockets, the first set of pockets opening at the opposite side of the membrane to the second set of pockets, manifold means in communication with the mouths of each of the first and second sets of pockets to feed and withdraw blood and oxygen in separate flow paths, each through a separate set of pockets, and a support member disposed in each of said pockets for holding adjacent laminae apart from each other and for providing flow paths of predetermined thickness, in which portions of said support members adjacent the ends thereof are of reduced aggregate thickness, to provide a portion of said blood flow path of increased thickness in contact with said membrane and oxygen flow path, whereby blood flowing through said blood flow path portion of increased thickness is conditioned for relatively increased carbon dioxide diffusion through said membrane, while along the portions of said support members remote from the ends thereof, blood is conditioned for relatively increased oxygen diffusion through said membrane.

Claim 13

The blood oxygenator of claim 9 in which said diffusion membrane comprises a mesh over which is applied a thin cover of silicone rubber sufficient to fill the spaces of said mesh.

Claim 14

The blood oxygenator of claim 9 in which said support members comprise screens made of a mesh of crossing strands.

Claim 15

The blood oxygenator of claim 9 in which the exchange surface area of said flow path portions of increased thickness is not less than 15 percent of the exchange surface area of the remaining flow path portions within said pockets.

Claim 16

A fluid diffusion cell, including a selectively permeable diffusion membrane, folded to form laminae defining alternately positioned first and second sets of pockets, the first set of pockets opening at the opposite side of the membrane to the second set of pockets, the improvement comprising first fluid inlet means and first fluid outlet means in communication with the first set of pockets and located at the mouths thereof, and second fluid inlet means and second fluid outlet means in communication with the second set of pockets and located at the mouth thereof, each inlet and outlet means having an enlarged external chamber, open to the mouths of each pocket of a set, to provide flow paths to each pocket of approximately equal length, a medial member between each inlet and outlet means pressing against the mouths of said pockets to force fluid to flow into and through said pockets while passing from each inlet to each outlet means, the first and second sets of pockets defining separate parallel flow paths for respective fluids, and a support member disposed in each of said pockets for holding adjacent laminae apart from each other and for providing flow paths of predetermined thickness, the length of said flow paths in the pockets being greater than the dimension of said fluid diffusion cell which is perpendicular To said laminae, said selectively permeable diffusion membrane comprising a meshlike support element of biologically inert material, in which the interstitial spaces defined by the meshlike support element are filled with a thin film of selectively permeable elastomer material.

Claim 17

A fluid diffusion cell, including a selectively permeable diffusion membrane, folded to form laminae defining alternately positioned first and second sets of pockets, the first set of pockets opening at the opposite side of the membrane to the second set of pockets, the improvement comprising first fluid inlet means and first fluid outlet means in communication with the first set of pockets and located at the mouths thereof, and second fluid inlet means and second fluid outlet means in communication with the second set of pockets and located at the mouth thereof, each inlet and outlet means having an enlarged external chamber, open to the mouths of each pocket of a set, to provide flow paths to each pocket of approximately equal length, a medial member between each inlet and outlet means pressing against the mouths of said pockets to force fluid to flow into and through said pockets while passing from each inlet to each outlet means, the first and second sets of pockets defining separate parallel flow paths for respective fluids, and a support member disposed in each of said pockets for holding adjacent laminae apart from each other and for providing flow paths of predetermined thickness, the length of said flow paths in the pockets being greater than the dimension of said fluid diffusion cell which is perpendicular To said laminae, said selectively permeable diffusion membrane comprising a meshlike support element of biologically inert material, in which the interstitial spaces defined by the meshlike support element are filled with a thin film of selectively permeable elastomer material.

Claim 18

The fluid diffusion cell of claim 13 in which said support members in the pockets comprise screens made of a mesh of crossing strands.