DEVICE FOR SUBSTANCE EXCHANGE AND METHOD FOR THE PRODUCTION THEREOF

Abstract

A device for substance exchange between a first medium, in particular blood, and a second medium, in particular a gas/gas mixture, includes a housing element in which there is arranged a hollow-fiber bundle containing substance-permeable hollow fibers which extend axially between the axial ends of the housing element and at their respective axial end region are potted with a potting compound, at least among one another, and around which the first medium can flow and through which the second medium can flow. Also, a method for producing the device is provided.

Claims

1. A device for substance exchange between a first medium and a second medium comprising a housing element in which there is arranged a hollow-fiber bundle containing substance-permeable hollow fibers which extend axially between axial ends of the housing element and at their respective axial end region are potted with a potting compound, at least among one another, and around which the first medium can flow and through which the second medium can flow, wherein the housing element, at at least one of the axial ends is closed by a cover element which has a media connection in fluidic communication with the axially open ends of the hollow fibers, wherein at at least one of the axial ends of the housing element an outer sealing ring surrounding the hollow-fiber bundle is formed from the potting compound arranged between the hollow fibers, which outer sealing ring extends in the radial direction at least in part between axial end faces of the housing element and of the cover element and is compressed between these, and at at least one of axial ends of a winding core which carries the hollow fibers an inner sealing ring arranged on an inner circumference of the hollow-fiber bundle is formed from the potting compound arranged between the hollow fibers, which inner sealing ring extends in the radial direction at least in part between axial end faces of the winding core and of a plug in the cover element and is compressed between these.

2. The device as claimed in claim 1, wherein the outer and/or inner sealing ring is in one piece with or cohesively bonded to the potting compound between the hollow fibers.

3. The device as claimed in claim 1, wherein the potting compound is formed by an elastomer.

4. The device as claimed in claim 1, wherein the axial end face of the housing element and/or of the cover element has, radially inwardly, an axially and radially inwardly open recess, in which the outer sealing ring lies compressed, and/or the axial end face of the winding core and/or of the plug in the cover element has, radially outwardly, an axially and radially outwardly open recess, in which the inner sealing ring lies compressed.

5. The device as claimed in claim 4, wherein an axial, annular projection is arranged radially inwardly on one of the end faces of housing element or cover element and lies at least in part in the axially open recess in the end face of the opposite element, or an axial, annular projection is arranged radially outwardly on one of the end faces of the winding core or of the plug in the cover element, which projection lies at least in part in the axially open recess in the end face of the opposite element.

6. The device as claimed in claim 5, wherein the outer sealing ring is extended in a radial direction outward beyond the projection and overhangs it and, by a stepped region at the recess of the opposite element, is bent axially into a region which is arranged set back radially outwardly from the projection and axially behind the projection, and/or the inner sealing ring is extended in the radial direction inwardly beyond the projection and overhangs it and, by a stepped region at the recess of the opposite element is bent axially into a region which is arranged set back radially inwardly from the projection and axially behind the projection.

7. A method for production of a device for substance exchange between a first medium and a second medium as claimed in claim 1, wherein a hollow-fiber bundle surrounding a winding core, with substance-permeable hollow fibers extending between axial ends of the housing element, is arranged in a housing element of the device, which hollow fibers, after closure of the housing element at at least one of its axial ends are potted at least among one another at their axial end region which is covered by a potting and, after the potting cover is removed, the potted hollow fibers are opened at their axial ends, and the housing element is tightly sealed with a cover element, wherein, simultaneously with the potting of the hollow fibers among one another, a sealing ring surrounding the hollow-fiber bundle radially on the outside is created from the potting compound, by the potting compound flowing into an annular gap formed between the end faces of housing element and potting cover and, simultaneously with the potting of the hollow fibers among one another at the inner circumference of the hollow-fiber bundle, an inner sealing ring is created from the potting compound, by the potting compound flowing into an annular gap formed between the end faces of a winding core, which carries the hollow-fiber bundle, and a cover element in the potting cover covering the winding core.

8. The method as claimed in claim 7, wherein the annular gap is defined by an axially and radially inwardly open recess in the end face of the housing element and/or of the potting cover, and/or the annular gap is defined by an axially and radially outwardly open recess in the end face of the winding core and/or of the cover element in the potting cover.

9. The method as claimed in claim 7, by cutting off potted hollow-fiber ends or also by separating hollow-fiber ends closed by the manufacturer, the outer sealing ring and/or the inner sealing ring is also separated from the bonded hollow-fiber bundle, wherein the outer sealing ring remains in a recess, open at least in the axial direction, in the end face of the housing element, and, by placement of the cover element, is compressed between the end faces of cover element and housing element, and/or the inner sealing ring remains in a recess, open at least in the axial direction, in the end face of the winding core, and, by placement of the plug, is compressed between the end faces of plug and winding core.

10. The method as claimed in claim 7, after the opening of the hollow-fiber ends by cutting off potted hollow fiber ends or also by separating hollow-fiber ends closed by the manufacturer, the outer sealing ring and/or the inner sealing ring remain attached to the hollow-fiber bundle by cohesive bonding or integral connection, wherein the outer sealing ring, by placement of the cover element, is compressed between the end faces of cover element and housing element, and/or the inner sealing ring, by placement of the plug, is compressed between the end faces of plug and winding core.

11. The method as claimed in claim 7, wherein the shape of the annular gap defined between potting cover and housing element forms an outer sealing ring which, after removal of the potting cover, a. lies in a recess arranged radially inwardly in the end face of the housing element, protruding in the axial direction beyond the end face region of the housing element surrounding the recess, and, by placement of the cover element is compressed into the recess by an axial projection arranged radially inwardly on the end face of the cover element, or b. rests at a predetermined height on a planar surface region of the end face of the housing element that is formed in the radial extent without a recess and, by placement of the cover element, is compressed in an axially and radially inwardly open recess in the end face of the cover element, to a depth less than the predetermined height, or c. covers a radially inner axial projection in the end face of the housing element and protrudes outward in the radial direction and, upon placement of the cover element, is compressed by a recess surrounding the projection in the end face of the cover element and bent in the axial direction.

12. The method as claimed in claim 7, wherein the shape of the annular gap defined between the cover element in the potting cover and the winding core forms an inner sealing ring which, after removal of the cover element and of the potting cover, a. lies in a recess arranged radially outwardly in the end face of the winding core, protruding in the axial direction beyond the end face region of the winding core lying radially inward from the recess, and, by placement of the plug, is compressed into the recess, in particular by an axial projection arranged radially outwardly on the end face of the plug, or b. rests at a predetermined height on a planar surface region of the end face of the winding core that is formed in the radial extent without a recess and, by placement of the plug, is compressed in an axially and radially outwardly open recess in the end face of the plug, to a depth less than the predetermined height, or c. covers a radially outer axial projection in the end face of the winding core and protrudes inward in the radial direction and, upon placement of the plug, is compressed by a recess surrounding the projection in the end face of the plug and bent in the axial direction.

Description

[0065] FIG. 1 shows a first step of the production method, in which a hollow-fiber bundle 2 is inserted into the housing element 1, which hollow-fiber bundle 2 protrudes axially beyond the parting plane TE between housing element 1 and potting cover 3 or the distal end face plane SE of the housing element 1. The housing element 1 is closed axially with the potting cover 3, and the end of the hollow-fiber bundle 2 is surrounded by a tubular portion 3a of the potting cover 3.

[0066] The hollow-fiber bundle is formed here, for example, by a winding of hollow fibers which are connected to at least one mat with warp threads, for example, with the winding being carried on a winding core 2a, which in particular can also remain subsequently in the housing element 1. A cover element 3b arranged on the potting cover 3 lies axially opposite the winding core 2a, in particular covering its axial end face and being in contact therewith. The cover element 3b can be formed in one piece with the potting cover 3 or is separate from it. For example, in the case of a separate design, it can be clamped between the potting cover 3 and the winding core 2a.

[0067] Both annular end faces of housing element 1 and potting cover 3 have respective radially inward recesses 1.1 and 3.1, which are open axially and radially inwardly and thus form an annular gap on the inner wall of the closed arrangement, i.e. of the whole housing. In this embodiment, the annular gap 1.1, 3.1 lies axially around the parting plane TE of the two elements 1, 3, which plane coincides with the distal end face plane SE of the housing element 1. The distal end face of the housing element preferably lies in the same plane as the distal end face of the winding core 2a.

[0068] In addition to the outer annular gap thus formed, which results radially on the outside around the hollow fibers and is provided at least in the invention, this embodiment also provides that an inner annular gap also results radially on the inside of the hollow fiber bundle 2. This inner annular gap is formed between the winding core 2a and the cover element 3b. For this purpose, the cover element 3b and the winding core 2a each have respective radially outward recesses 3b.1 and 2a.1, which are open axially and radially on the outside. The inner annular gap 2a.1, 3b.1 also lies axially around the parting plane TE.

[0069] FIG. 2 shows the same arrangement after potting at the axial end. The potting compound 4 has here covered the hollow-fiber ends, having possibly closed them if they were not closed by the manufacturer, and has also penetrated into the outer annular gap formed by the recesses 1.1 and 3.1 and also into the inner annular gap formed by the recesses 3b.1 and 2a.1 and has thus formed an outer sealing ring 5a, which surrounds the hollow-fiber bundle 2 on the outside, and formed an inner sealing ring 5b, which is arranged on the inside along the inner circumference of the hollow-fiber bundle 2.

[0070] FIG. 3a shows the arrangement after removal of the potting cover 3 and also of the cover element 3b. FIG. 3b shows the same arrangement after some of the potted hollow fibers have been separated in order to open them.

[0071] The separation takes place in the separation plane AE at a distance from the sealing rings 5a/5b which, in this embodiment, extends beyond the distal end face plane SE of the housing element 1.

[0072] FIG. 4 shows the situation after the cover element 6 of the device has been put in place. The cover element 6 is, in particular similarly to the potting cover 3, pot-shaped and has a top surface, preferably an outwardly curved top surface 6a, from which a tubular portion 6b extends axially in the direction of the housing element 1, which tubular portion 6b in part surrounds the potted hollow-fiber ends.

[0073] The cover element 6 also has a connection 6.3 in order to convey gas to the open hollow fibers and away from them. Here, the cover element 6 has no recess in the end face region interacting with the distal end face 1.2 of the housing element 1 for the purpose of sealing, and it compresses the outer sealing ring 5a when the end face is placed onto the axially projecting region of the outer sealing ring 5a.

[0074] The inner sealing ring 5b is compressed by a plug 6c, which in particular can be an integral part of the cover element 6 or can also be designed separately from the latter. The plug 6c lies in contact with the winding core 2a. In particular, the plug 6c, preferably when separate from the cover element 6, can be attached to the winding core 2a, e.g. by latching or screwing or the like. This may also apply in all possible embodiments, including those not shown.

[0075] FIG. 5a shows an alternative in which the end face of the housing element 1 lies in a single plane, i.e. has no recess. The equally steplessly planar end face of the winding core 2a lies in the same plane and also has no recess. An axially and radially inwardly open recess 3.1 is arranged only in the end face of the potting cover 3 in order to form the outer annular groove, and an axially and radially outwardly open recess 3b.1 is arranged only in the cover element 3b in order to form the inner annular groove.

[0076] In the finished device according to FIG. 5b, the outer sealing ring 5a lies only in a radially inwardly and axially open recess 6.1 and is compressed by the latter, since the depth of the recess 6.1 is less than the height of the sealing ring 5a above the end face of the housing element 1. The inner sealing ring 5b lies only in a radially outwardly and axially open recess 6c.1 and is compressed by the latter, since the depth of the recess 6c.1 in the plug 6c is less than the height of the sealing ring 5b above the end face of the winding core 2a.

[0077] FIG. 6a shows an embodiment in which only one radially inwardly and axially open recess 1.1 is arranged in the housing element 1. The axial end face of the potting cover 3 lies in a single plane (without a recess) and covers the recess 1.1 in the end face of the housing element 1, which is stepped by the recess 1.1.

[0078] The outer sealing ring 5a formed according to FIG. 6b thus lies in the distal end face plane SE of the housing element 1 and does not protrude beyond the recess 1.1. For compression, the cover element 6 now has, radially inwardly on its end face, an axial annular projection 6.2 which is directed toward the housing element 1 and which partially engages in the recess 1.1, filled with the sealing ring 5a, on the end face of the housing element 1.

[0079] As regards the inner sealing ring 5b, this too lies in the distal end face plane SE of the housing element 1 or of the winding core 2b and does not protrude beyond the recess 2b.1. For compression, the plug 6c now has, radially outwardly on its end face, an axial annular projection 6c.2 which is directed toward the winding core 2a and which partially engages in the recess 2a.1, filled with the sealing ring 5b, on the end face of the winding core 2a.

[0080] FIGS. 7a and 7b show an embodiment in which the finished outer sealing ring 5a in the finished device (FIG. 7b) covers a radially inner projection 1.2 in the housing element 1 and also projects radially beyond it in a radially outward direction. The protruding part of the sealing ring 5a is bent and compressed in the axial direction by a step 6.1.a of the axially and radially inwardly open recess 6.1 in the end face of the cover element 6. The step 6.1.a delimits the recess 6.1 radially on the outside.

[0081] It is also the case that the inner sealing ring 5b in the finished device (FIG. 7b) covers a radially outer projection 2a.2 in the winding core 2a and also protrudes radially beyond it in a radially inward direction. The protruding part of the sealing ring 5b is bent and compressed in the axial direction by a step of the axially and radially outwardly open recess 6c.1 in the end face of the plug 6c. The step delimits the recess 6c.1 radially on the inside.

[0082] In FIG. 7a it can be seen that an outer sealing ring 5a overhanging the projection 1.2 can be produced during potting by filling the radially outwardly recessed region radially behind the projection 1.2, for example with a filling ring 7a, which is removed again before the cover element 6 is put in place. The filling ring 7a results in a radially outer region of the annular gap 3.1 that is supported in the axial direction, such that an outer sealing ring 5a extending radially in a straight line can be produced, which protrudes outward beyond the projection 1.2 in the radial direction. In the region filled by the filling ring 7a during the potting process, the outer sealing ring 5a can be bent by the cover element 6 after the filling ring 7a has been removed.

[0083] Furthermore, an inner sealing ring 5b overhanging the projection 2a.2 can be produced during potting by filling the radially inwardly recessed region behind the projection 2a.2, e.g. with a filling ring 7b, which is removed again before the plug 6c is put in place. The filling ring 7b results in a radially inner region of the annular gap 3b.1 that is supported in the axial direction, such that an inner sealing ring 5b extending radially in a straight line can be produced, which protrudes inward beyond the projection 2a.2 in the radial direction. After removing the filling ring 7b, the inner sealing ring 5b can be bent by the plug 6c in the region filled by the filling ring 7b during the potting process.