DE102015015149B3 - A hollow fiber membrane filtration apparatus and method of making the same - Google Patents

Abstract

Suggested is u. a. a hollow fiber membrane filtration device (1) for body fluids comprising a bundle (3) of hollow fibers (4) and a housing (2) extending along the bundle (3) of hollow fibers (4). The housing (2) defines an internal space (7) for the bundle (3) hollow fibers (4), which is cast into a potting compound (9) at both ends. The housing (2) has at least one interlocking means (16) with a free end (16b), which interlocking means (16) of the potting compound (9) is at least partially enclosed. The positive-locking means (16) is formed by two or more extensions (16a) arranged at a distance from one another and connected at one end to the housing wall (6). Starting from an orthogonal (20) on a central longitudinal axis (10) of the housing (2) are the extensions (16 a) by an inclination angle "α" in the interior of the housing (2) into the one or the other end of the filtration device (1) formed inclined.

Description

The invention is based on the preamble of claim 1 of a hollow fiber membrane filtration device for body fluids, with a bundle of hollow fibers and with a longitudinally extending along the bundle of hollow fibers housing with a housing, which housing defines an interior in which the bundle is arranged hollow fibers, wherein the bundle of hollow fibers is cast into a potting compound at both ends, and wherein the housing has on the inside at least one positive locking means with a free end, which positive locking means is at least partially enclosed by the potting compound. According to claim 15 of the invention further relates to a method for producing a hollow fiber membrane device.

From the EP 0 305 687 B1 a filtering device is known whose both ends are disc-shaped curing potting compound enclosed in each case by an intermediate ring to which the potting compound does not adhere. In this case, said ring consists for example of polypropylene (PP) whereas the potting compound consists of, for example, polyurethane (PUR). By this relatively complex measure, a stress-free shrinkage of the potting compound should be ensured, which in turn should be prevented stress cracks in the potting compound. In addition, the disk-shaped potting compounds are supported so that a movement of the same is prevented in the longitudinal direction. This is effected by a radially directed flange of said ring. Such forces in the longitudinal direction are particularly noticeable when after pouring the ends of the hollow fiber bundle in said potting compound and curing the hollow fibers are opened by a cut. From the EP 0 844 015 B1 a filtration device with a housing is known, which housing has axial and resilient tooth or crenellated projections which in turn define an annular space arranged between them and the housing. The notches or incisions between the tooth or crenellated projections are partially incorporated into the potting compound, whereby a certain form fit between the projections and the potting compound is effected while ensuring a stress-free shrinkage of the potting compound. The tooth or crenellated projections may have radially outwardly directed projections at their ends. The housing consists of a material such as polypropylene (PP), which does not seal tightly with the potting compound of z. B. polyurethane (PUR) received. From the EP 1 926 546 B1 is a to the above EP 0 844 015 B1 leaning filter device with formed by free-running, axial notches or incisions tooth or crenellated projections of the housing of the filtration device, wherein the housing between the teeth or crenellated projections of these outgoing projections which extend to the adjacent tooth or crenellated projection. From the US 5,472,601 A a filtering device is known, the housing has a connecting element in the form of a so-called stop ring, which is cast in potting compound and whose thickness, starting from the housing wall increases from radially outside to radially inside. From the US 2005/0115885 A1 a filtration device with a housing is known, which has a ring with a radially inwardly directed and embedded in potting compound annular anchor element.

Further filtration devices of the generic type are further from the US 2015/0165106 A1 , of the US Pat. No. 6,830,685 B2 , of the EP 1 616 617 A1 and the JP 2005-161 305 A known. That's how it describes US 2015/0165106 A1 a filtration device, respectively a capillary dialyzer, which has at both ends a respective attached to the housing of the filtering device and cast in potting compound support ring. On the support ring a plurality of evenly distributed over the circumference of the same arranged ribs are formed. The US Pat. No. 6,830,685 B2 describes a filtering device, which has both ends a tightly attached to the housing of the same ring with an annular anchor. The said anchor is cast in potting compound. The ring with the anchor is made of polypropylene (PP), whereas the potting compound is made of polyurethane (PUR). The EP 1 616 617 A1 describes a filtering device which has a ring-shaped body with a radially inwardly facing, annular projection at both ends. The annular bodies are each supported so as to be spaced apart on the housing of the filtration device by means of a plurality of circumferentially distributed and radially outwardly facing projections so as to realize fluid passages or channels between the housing wall and the annular body. At least the radially inwardly facing annular projection is received by a sealing element not described in detail. The JP 2005-161 305 A describes a filtering device with a cylindrical housing, which is on the cap side each formed in the manner of an annular cage, with evenly distributed over the circumference of the same axially aligned rod elements, which are connected to each other at both ends. Between the respective cage and a cap closing off the housing, an annular space is formed. The incisions of the cage formed between the rod elements are partially embedded in casting resin.

All of these, known from the prior art solutions has in common that they are not reliably limit the resulting, for example, when opening the hollow fibers by trimming the ends of the same voltages and / or relatively expensive to implement.

The object of the invention is therefore to provide a hollow-fiber membrane filtration apparatus improved with respect to the state of the art, which, while retaining the advantages of the prior art, ensures in a particularly simple and advantageous manner a firm bond between the housing of the filtration apparatus and the potting compound. It is another object of the invention to provide a method for producing such a hollow-fiber membrane filtration device, which is particularly simple and inexpensive to carry out.

This object is achieved in the generic device by the features of claim 1. Further embodiments of the invention are the subject of the dependent claims 2 to 14.

According to the invention, the object is achieved in conjunction with the features in the preamble of claim 1, characterized in that the at least one positive locking means by two or more, seen in the circumferential direction of the housing spaced from each other and one end connected to the housing extensions formed, each starting are formed by an imaginary, the terminal portion of the relevant extension of the housing by passing through orthogonal to a central longitudinal axis of the housing by a defined angle of inclination "α" in the interior of the housing into one or to the other end of the filtration device out inclined.

Under said connection area, which may also be referred to as the foot area of the respective extension, the end of the extension opposite the free end of the respective extension is understood, which is supported on the housing wall and represents, so to speak, the transition from the extension to the housing wall.

By this measure, a filtering device is provided, which ensures the same with a simple production of a solid bond between the housing of the filtration device and the potting compound together with the bundled at its ends hollow fibers. Due to the deliberately inclined arrangement of the extensions of the applied to the cured potting compound resistance to axial withdrawal is increased, which is particularly advantageous if after pouring the ends of the hollow fiber bundle in said potting compound and curing the same hollow fibers by trimming the ends of the hollow fibers be opened transversely to the longitudinal extent of the same. In addition, the risk of damage to the hollow fibers is effectively avoided by excessive, acting on the hollow fibers tensile force due to said cut.

According to a first preferred embodiment of the invention, the at least one positive locking means is integrally formed with the housing, resulting in savings in particular material, manufacturing and assembly costs.

However, the invention is not limited to a one-piece design of the housing with the extensions according to the first preferred embodiment of the invention, but detected according to a second embodiment of the invention also extensions that collectively form at least one separately manufactured, for example, one-piece, annular attachment and the housing or the inner contour of the housing wall fixed, preferably firmly bonded fixed, in particular with the same or the same welded or glued. However, the at least one attachment itself may also be formed two or more parts, for example, be formed by ring segments, which is accordingly also covered by the invention.

In a further development of the invention it can be provided that the extensions of the at least one positive locking means are resiliently formed at least in their connection region to the housing wall. Due to the resilient design of at least the terminal portions of said extensions and the inclined orientation of the extensions a simple production of the housing of the filtration device including the integrally formed with the same extensions according to, for example, a plastic injection molding in a single step in a simple design demolding possible. While the demolding give way to the extensions, but can then take advantage of their desired inclined arrangement again automatically. However, the invention is not limited to the said plastic injection molding process, but covers any suitable, plastic processing method for producing the housing, such as the production of the same by 3D printing.

As far as the said second embodiment variant of the invention is concerned, in this case a resilient design of at least the connecting regions of said extensions is possible, but not absolutely necessary.

According to a practical embodiment of the invention, the inclination angle "α" is preferred formed between said orthogonal and an imaginary line, which straight line in the connection region of the relevant extension to the housing wall intersects the orthogonal and on the other connects the resulting intersection with one of the housing wall nearest point at the free end of the extension.

In a further development of the invention, it is further provided that, starting from the orthogonal, the angle of inclination "α" is determined by the relationship 0 ° <| α | <90 ° is selected.

In experiments on the subject of the application, in particular, an angle of inclination "α" has proven successful, which, starting from the orthogonal, ranges from preferably ± 10 ° to ± 80 °, more preferably from ± 40 ° to ± 70 °, even more preferably is selected from a range of ± 50 ° to ± 65 °.

A simple and functionally reliable embodiment of the invention is further achieved in that the connection regions of the extensions or all extensions of the respective positive locking means are preferably arranged in a common, aligned orthogonal to said central longitudinal axis of the housing first level. In contrast, it may also be indicated and is accordingly covered by the invention that the connection areas of a first part of the extensions of the respective positive locking means in a orthogonal to said central longitudinal axis of the housing aligned first level and the terminal portions of at least a second part of said extensions in one of first level parallel second level are arranged. As a result, viewed in the longitudinal direction of the housing, advantageously, a larger area of the housing wall is integrated into the introduction of force, as a result of which the local load on the housing wall is reduced and, as a consequence, this can be designed to be thinner-walled than is conventional. Furthermore, as a result, the most varied variants of the alignment and arrangement of the projections in one, two or more levels can be realized.

As the invention further provides, all extensions of the respective positive locking means can be arranged inclined to the one or to the other end of the housing. Alternatively, extensions of the respective positive locking means may also be arranged regularly or irregularly alternately to the one or to the other end of the housing inclined. Which variant is specifically taken into account depends in particular on the materials used for the potting compound and the extensions and on the currently acting longitudinal or axial forces. For those skilled in the art, it goes without saying that directed against the direction of action of the said longitudinal forces extensions apply the greatest resistance to axial withdrawal of the cured potting compound during the cutting of the bundle of hollow fibers transverse to the longitudinal extent of the hollow fibers.

Preferably, the extensions are uniform in the circumferential direction, d. H. arranged distributed with equal spacing to each other around the bundle of hollow fibers. As a result, the forces acting on the potting compound can be optimally introduced into the housing by means of the extensions.

In order to further increase the bond between the projections and the casting compound, it is preferably provided that at least one of the extensions has at least one opening, a recess, a bead-like formation and / or an angling at the free end of the extension. Due to the above-described resilient design of at least the terminal portions of the extensions can in the manufacture of the housing after, for example, a plastic injection molding consuming slide etc. for the formation of said openings, recesses, undercuts and / or the like. Be more unnecessary.

In order to further improve the bond between the potting compound and the extensions, it can be provided that the spacing between adjacent projections in the circumferential direction of the housing is taken up by an elastic wall element connecting at least partially the relevant extensions, wherein the elasticity of the wall element is greater than the elasticity the extensions is. It is thus a closed ring alternately formed with smaller sections and in relation to greater elasticity, whereby any tensile forces on the potting compound together with hollow fibers, which may arise when trimming the potting compound together with hollow fibers, better transferred to the total cross section of the potting compound together with hollow fibers and by the same Avoidance of damage can be effectively absorbed and / or introduced into the housing wall. In addition, the centering of the bundle of hollow fibers in the housing of the filtration device is optimized by this measure.

Preferably, the housing together with extensions or the housing together with the at least one attachment with projections made of a material that does not receive an adhesive bond with the potting compound. More preferably, in this case, the housing together with projections or the housing together with the at least one attachment with projections at least one polyolefin, in particular polypropylene (PP) or Polyethylene (PE), and the potting compound polyurethane (PUR), resulting in particular savings in material costs compared to widely used materials, such as polycarbonates (PC), which enter into a better adhesion with the potting compound. Preferably, the housing together with extensions or the housing together with the at least one attachment with projections material of uniform design. However, the invention is not limited to this preferred embodiment, but also covers a combination of different materials, which are processed for example by a multi-component plastic injection molding.

• a) Bereitstellung eines Gehäuses, das beidenends innenraumseitig wenigstens ein Formschlussmittel mit einem freien Ende aufweist, welches Formschlussmittel durch zwei oder mehrere, in Umfangsrichtung des Gehäuses gesehen voneinander beabstandet angeordnete und einenends an die Gehäusewandung angeschlossene Fortsätze gebildet ist, die jeweils ausgehend von einer gedachten, den Anschlussbereich des betreffenden Fortsatzes an die Gehäusewandung durchsetzenden Orthogonalen auf eine Mittenlängsachse des Gehäuses um einen definierten Neigungswinkel „α” in das Innere des Gehäuses hinein zu dem einen oder zu dem anderen Ende der Filtriervorrichtung hin geneigt ausgebildet sind,
• b) Anordnung eines Bündels Hohlfasern innerhalb des Gehäuses derart, dass die Enden des Bündels Hohlfasern von den Fortsätzen des zugeordneten wenigstens einen Formschlussmittels eingefasst sind,
• c) beidenends des Gehäuses Einbringen einer Vergussmasse in das Gehäuse derart, dass zum einen die Enden des Bündels Hohlfasern von der Vergussmasse umschlossen werden und zum anderen die Vergussmasse die Fortsätze zumindest teilweise einfasst, und
• d) nach Aushärten der Vergussmasse Öffnen der Enden der Hohlfasern durch einen Beschnitt der Enden der Hohlfasern quer zur Längserstreckung derselben.

According to claim 15 of the invention also relates to a method for producing a hollow fiber membrane filtration device of the type described above. This method is characterized by the following steps:

• a) providing a housing which has on both sides on the inside at least one positive locking means with a free end, which positive locking means is formed by two or more, viewed in the circumferential direction of the housing spaced apart and one end connected to the housing walls extensions, each starting from an imaginary, the connection region of the appendage to the housing wall passing through orthogonal to a central longitudinal axis of the housing by a defined angle of inclination "α" are formed in the interior of the housing into one or to the other end of the filtering device inclined towards
• b) arranging a bundle of hollow fibers within the housing such that the ends of the bundle of hollow fibers are enclosed by the extensions of the associated at least one positive locking means,
• c) both ends of the housing introducing a potting compound into the housing such that, on the one hand, the ends of the bundle of hollow fibers are enclosed by the potting compound and, on the other hand, the potting compound at least partially surrounds the extensions, and
• d) after curing of the potting compound opening the ends of the hollow fibers by trimming the ends of the hollow fibers transverse to the longitudinal extent thereof.

This method has the advantage that when changing the materials used, in particular when using non-adhesive materials for the production of a filter device according to the invention, only a very small effort and the existing production processes and production equipment can be largely retained.

The invention will be explained in more detail with reference to the embodiments schematically illustrated in the drawings. However, it is not limited to these, but covers all embodiments defined by the claims. Show it:

1 a side view of an inventively designed hollow fiber membrane filtration device,

2 a sectional view of the housing of the filtration device according to 1 with a form-fitting element according to the invention in the form of several extensions according to a first embodiment of the invention,

3 the housing of the filtration device after 2 Completed by a bundle of hollow fibers, which is poured into both sides of the housing in potting compound,

4 the detail "Z ₁ " after 2 (first embodiment),

5 the detail "Y" after 3 .

6 the detail "Z ₂ " after 2 according to a second embodiment,

7 the detail "Z ₃ " after 2 according to a third embodiment,

8th the detail "Z ₄ " after 2 according to a fourth embodiment,

9 the detail "Z ₅ " after 2 according to a fifth embodiment, and

10 according to the invention essential positive locking element 9 in a perspective individual representation.

Embodiment 1 (FIGS. 1 to 5):

According to the 1 to 3 consists of the hollow fiber membrane filtration device 1 for body fluids, in particular for hemodialysis, from a tubular housing 2 with exemplarily circular cross-section. The housing 2 consists of a plastic, preferably polypropylene (PP). The housing 2 has a middle housing section 2a and to the respective end thereof toward an end portion 2 B . 2c with one in each case in relation to the middle housing section 2a larger diameter.

Inside the case 2 is an elongated bundle 3 hollow fibers 4 arranged, which extends from one to the other end of the housing 2 extends and through the middle housing portion 2a of the housing 2 is centered in the same ( 3 ). The hollow fibers 4 are each formed by a semipermeable membrane and form by their non-illustrated tube or Kapillarröhren passages a first flow space 5 the filtration device 1 for said body fluid, in particular for blood. The housing 2 with its housing wall 6 extends along the bundle 3 hollow fibers 4 and defines an interior 7 and thus a second flow space 8th the filtration device 1 in which second flow space 8th a liquid, in the present case a dialysate is guided. The ends of the bundle 3 hollow fibers 4 are each in a potting compound 9 preferably polyurethane (PUR) cast or embedded. After hardening of the potting compound 9 this is largely disc-shaped.

This disc-shaped shape of the two ends of the housing 2 arranged potting compound 9 is caused by the fact that during the introduction of the potting compound 9 in the case 2 , the same preferably one perpendicular to the central longitudinal axis 10 of the housing 2 directed axis is centrifuged. The curing of the potting compound 9 takes place in temporarily provided and the respective end face of the housing 2 covering caps (not shown in the drawing), resulting in the potting compound 9 encircling the housing wall 6 and clings to the front caps. After curing of the respective potting compound 9 the end caps are removed. Thereafter, the respective potting compound 9 including the embedded or embedded hollow fibers 4 on its front side and transversely to the longitudinal extent of the hollow fibers 4 trimmed, whereby the process-related by the potting compound 9 closed tube or Kapillarröhrurchgänge the hollow fibers 4 be opened again. Of course, the steps may include removing the caps and trimming the potting compound 9 including hollow fibers 4 be performed in one step by said trimming (not shown in the drawing).

After removing the aforementioned caps is now the front side of the housing 2 one cap each 11a . 11b with first connection piece 12a . 12b attached, which measures the flow of body fluid (eg blood) through the hollow fibers 4 or the first flow space formed 5 guarantee. A cap 11a with connection piece 12a thus forms the inflow for the body fluid, whereas the other cap 11b with connection piece 12b forms the drain. Inflow and outflow are involved according to this embodiment in a flow circuit of a known per se and thus not graphically illustrated dialysis machine. The caps 11a . 11b including connection piece 12a . 12b are present non-positive / positive by screwing to the housing 2 connected. Of course, a cohesive joint connection can be provided by welding or gluing.

The said interior 7 of the housing 2 , also referred to as Dialysatraum, has in the region of its ends or in the region of the respective end portion 2 B . 2c one orthogonal to the central longitudinal axis 10 of the housing 2 aligned second connection piece 13a . 13b on. The second connecting pieces 13a . 13b serve the supply and discharge of the inner space 7 or second flow space 8th flowing through and thus the hollow fibers 4 around flowing dialysate. Also these connection pieces 13a . 13b are integrated in a flow circuit of the dialysis machine not shown in the drawing.

Because the potting compound 9 polyurethane (PUR) no adhesive bond and thus no tight joint connection with the housing 2 made of polypropylene (PP) and also causes the screw connection of the embodiment no liquid seal are in the region of the respective cap 11a . 11b two concentric ring seals 14 . 15 provided (cf. 5 ). The one, present radially inner ring seal 14 , seals the first flow space 5 against the second flow space 8th from and in particular supports axially on the potting compound 9 and on the adjacent cap 11a . 11b from. The second, radially outer ring seal 15 , seals the second flow space 8th against the outside atmosphere and supports in particular axially on a front edge of the housing 2 as well as on the adjacent cap 11a . 11b from. The ring seals 14 . 15 are within recesses of the housing 2 , the potting compound 9 and the cap in question 11a . 11b held so that they are fixed in the radial direction. The ring seals 14 . 15 can also be formed in one piece and thereby the first flow space 5 against the second flow space 8th and seal the outside atmosphere (not shown in the drawing). Any other suitable, known per se embodiments of the sealing of the flow spaces 5 . 8th to each other and to the outside atmosphere are of course included by the invention.

How very good from the 2 and 4 it can be seen has the housing 2 in the region of its two end sections 2 B . 2c each one positive locking means 16 with a free end 16b on. The respective positive locking means 16 is through several extensions 16a , according to this embodiment by twelve extensions 16a educated. All extensions 16a of the respective positive locking means 16 in the relevant end section 2 B . 2c are at one end to the housing 6 of the housing 2 connected and in a common, orthogonal to the center longitudinal axis 10 of the housing 2 arranged aligned first level.

Furthermore, the extensions 16a in the assembly of the housing 2 with the bundle 3 hollow fibers 4 and in the circumferential direction of the housing 2 preferably uniformly around the bundle 3 hollow fibers 4 distributed and spaced apart. The said extensions 16a are made according to this embodiment by a plastic injection molding and integral with the housing 2 or its housing wall 6 educated. This is done for example by means of a per se known plastic injection mold with two concentric mutually arranged Zugkernen for each side, which are movable only in the axial housing direction (not shown in the drawing).

In addition, all extensions are 16a of the respective positive locking means 16 in the relevant end section 2 B . 2c According to a preferred first embodiment variant of the invention, starting from an imaginary, the connection region of the respective extension 16a to the housing wall 6 enforcing orthogonal 20 on the middle longitudinal axis 10 of the housing 2 by a defined angle of inclination "α" in the interior of the housing 2 into the adjacent end of the filtration device 1 or to the respective adjacent cap 11a . 11b formed inclined towards the same (see, in particular 4 ). Furthermore, the extensions 16a at least in their connection area to the housing wall 6 spring-elastic design. Said spring elasticity of one piece with the housing 2 trained extensions 16a can be effected for example by a material thinning in said connection area. In contrast, the spring elasticity can also be effected by an elastomer, which is molded by a multi-component plastic injection molding process.

Under said connection area, which also serves as the foot area of the extension 16a This can be called the free end 16b of the respective extension 16a opposite end of the extension 16a understood, which is on the housing wall 6 supports and is firmly connected to the same and, so to speak, the transition from the extension 16a to the housing wall 6 represents, in this case due to integral formation of the extension 16a with the housing 2 or its housing wall 6 ,

By at least in the said connection area to the housing wall 6 elastic training of the extensions 16a is the demolding of the housing 2 simple and inexpensive accomplishable without the desired inclined orientation of the extensions 16a adversely affect. The inclination angle "α" is based on the orthogonal 20 according to the relation 0 ° <| α | <90 ° selected. In experiments on the subject of the application, an angle of inclination "α" has proven useful, starting from the orthogonal 20 is preferably selected from a range of ± 10 ° to ± 80 °, more preferably from a range of ± 40 ° to ± 70 °. However, particularly good results were obtained with an inclination angle "α" selected from a range of ± 50 ° to ± 65 °. With regard 4 is the inclination angle "α" according to this embodiment about 58 °. In experiments on the subject of the application, it has been found that it is precisely with this inclination angle "α" of approximately 58 ° that the extensions 16a can be particularly easily produced regardless of the chosen manufacturing process and the desired solid connection with the potting compound 9 and indirectly via said potting compound 9 with the hollow fibers 4 Offer.

As in particular the 2 . 4 and 5 it can be seen further, are the extensions 16a according to this embodiment, as far as possible in the manner of a free end 16b formed the same tapered cuboid and each have a radial opening 17 on. During the introduction of the potting compound 9 in the case 2 become the extensions 16a in the potting compound 9 embedded and so is a positive connection between the potting compound 9 and the extensions 16a causes. The potting compound penetrates 9 the extensions 16a through said openings 17 through, whereby the positive connection is further improved. However, the invention is not limited to said openings 17 but also detects, for example, recesses on the extensions 16a , bead-like formations leading to the interior of the case 2 or outside the case 2 may be directed, and / or one, two or more bends at the free end 16b of the respective extension 16a , which also to the interior of the housing 2 or outside the case 2 may be directed (not shown in the drawing). Furthermore, the invention is not limited to cuboid extensions 16a but also covers extensions 16a , for example, have a shape that is similar to the basic shape of a trapezium, a triangle or a ring segment (not shown in the drawing).

Embodiment 2 (FIG. 6):

The 6 shows a second embodiment of the invention, wherein functionally identical parts are denoted by the same reference numerals as in the preceding drawings, so that reference is also made to the explanation and understanding of the above description.

The above-described preferred first embodiment of the invention focuses on a housing 2 from where all are integral with the housing 2 trained extensions 16a of the respective positive locking means 16 in the relevant end section 2 B . 2c by a selected angle of inclination "α" to the respective adjacent end of the filtering device 1 or to the respective adjacent cap 11a . 11b are inclined towards. However, the invention also covers an embodiment of the invention, in accordance with 6 all in one piece with the housing 2 trained extensions 16a of the respective positive locking means 16 in the relevant end section 2 B . 2c by a defined or selected angle of inclination "α" not to the respective adjacent end of the filtration device 1 or to the respective adjacent cap 11a . 11b but each to the opposite end of the filtering device 1 or to each opposite arranged cap 11a . 11b are inclined towards. Likewise is an arrangement of extensions 16a of the respective positive locking means 16 in the relevant end section 2 B . 2c with recorded, at the extensions 16a regular, ie alternating, or irregularly changing to one or the other end of the filtering device 1 are inclined (not shown in the drawing). It is understood by regularly or alternately alternately that alternately an equal number of extensions 16a in one or the other direction are directed or inclined. In contrast, it is understood by changing irregularly that alternately an uneven number of extensions 16a in one or the other direction are directed or inclined.

Embodiment 3 (FIG. 7):

The 7 shows a third embodiment of the invention, wherein functionally identical parts are designated by the same reference numerals as in the previous drawings, so that reference is also made to the explanation and understanding of the above description.

Thereafter, the invention is not limited to a single orthogonal to the central longitudinal axis 10 of the housing 2 aligned first level per end section 2 B . 2c of the housing 2 with all extensions 16a of the respective positive locking means 16 in the relevant end section 2 B . 2c but also detects two or more levels per end section 2 B . 2c with extensions 16a , So shows 7 an embodiment of the invention, in which at least one of the end portions 2 B . 2c of the housing 2 parallel to each other a first and a second orthogonal to the central longitudinal axis 10 of the housing 2 aligned plane, each with several extensions 16a are provided. To thereby demolding the extensions 16a in the manufacture of the housing 2 to facilitate, are the extensions 16a the two mutually parallel planes arranged offset from each other such that the extensions 16a one plane in the longitudinal direction of the housing 2 seen in the area of the spacing between the extensions 16a the other level are arranged.

Embodiment 4 (FIG. 8):

The 8th shows a fourth embodiment of the invention, wherein functionally identical parts are designated by the same reference numerals as in the previous drawings, so that reference is also made to the explanation and understanding of the above description.

To the bond between the potting compound 9 and the extensions 16a To improve further is according to 8th the spacing between in the circumferential direction of the housing 2 seen adjacent extensions 16a by an at least partially the relevant extensions 16a connecting elastic wall element 18 ingested. The elasticity of the wall element 18 is greater than the elasticity of the extensions 16a set. As a result, a closed ring is formed alternately with portions less and in relation to greater elasticity. Any tensile forces when trimming the potting compound 9 including hollow fibers 4 transverse to the longitudinal extent of the hollow fibers 4 on the potting compound 9 including hollow fibers 4 can work better in the overall cross section of the potting compound 9 including hollow fibers 4 transferred and effectively absorbed by the same while avoiding damage and / or in the housing 6 be initiated. In other words, a stress reduction of the known sensitive hollow fibers 4 as the acting forces are better in the housing 2 be initiated. In addition, by this measure, the centering of the bundle 3 hollow fibers 4 in the case 2 the filtration device 1 optimized. It is advantageously avoided that during the assembly of the housing 2 including positive locking means 16 with the bundle 3 hollow fibers 4 by axially inserting the bundle 3 hollow fibers 4 in the case 2 , single hollow fibers 4 in the spacing between the extensions 16a the positive locking means 16 advised and experienced damage such as buckling. The ones with the extensions 16a connected wall elements 18 that prefers the entire spacing between the extensions 16a occupy, act in combination with the extensions 16a in that regard, as an additional centering means, which an expansion of the ends of the bundle 3 hollow fibers 4 Effectively prevent and in general the fixation of the bundle 3 hollow fibers 4 in the case 2 improve. Due to the relatively greater elasticity of the wall element 18 to the extensions 16a is following the removal of the housing 2 with the extensions 16a a resilient recoil of the extensions 16a not hindered in the desired inclined arrangement.

Embodiment 5 (FIGS. 9 and 10):

The 9 and 10 show a fifth embodiment of the invention, wherein functionally identical parts are designated by the same reference numerals as in the preceding drawings, so that reference is also made to the explanation and understanding of the above description.

The embodiment according to the 9 and 10 differs from the previously described only in that the extensions 16a of the respective positive locking means 16 in the relevant end section 2 B . 2c summarized by at least one separately manufactured and on the housing 2 fixed attachment 19 are formed. According to 9 is the said attachment 19 exemplarily one-piece and annular and formed on the housing 2 or the inner contour of the housing wall 6 fastened or fastened. All extensions 16a are arranged here in a common plane. The ring-shaped attachment 19 has an annular base body 19a on, on which the extensions 16a are connected at one end. The main body 19a forms a fastening area of the positive locking means, so to speak 16 respectively its extensions 16a to the housing wall 6 off and is with the housing wall 6 preferably cohesively connected by welding or gluing or connectable.

The at least one attachment 19 However, it can also be designed in several parts, for example, be formed by two or more ring segments, which is accordingly also covered by the invention. Likewise, the extensions can 16a based on the above-described embodiment of the variant 3 The invention may be arranged in two or more planes (not shown in the drawing). Are all provided extensions 16a of the respective positive locking means 16 in the relevant end section 2 B . 2c Arranged in a single, common plane, the spring-elastic design favored for the above exemplary embodiment is at least the connecting regions of said extensions 16a not mandatory. Otherwise it may behave due to the preferred plastic injection molding process, if said attachment 19 projections 16a which are arranged distributed over two or more levels. In this case, it may be beneficial to the extensions 16a at least in their connection area to the housing wall 6 , in the present case realized indirectly via the interposed and acting as a mounting area and on the housing wall 6 fixed body 19a , spring elastic form.

The main body 19a in this case has a wall thickness and accordingly a strength and / or stiffness, the function of the positive locking means 16 does justice. In experiments, an optimal function of the positive locking means has 16 result when the wall thickness of the housing wall 6 directly connected body 19a largely the material thickness of the extensions 16a corresponds to 10 ).

Again, it may be indicated and is accordingly covered by the invention, in the spacings between the extensions 16a the wall elements described above 18 to provide with the described advantages (not shown in the drawing).

LIST OF REFERENCE NUMBERS

1

filtering

2

casing

2a

middle housing section

2 B

end

2c

end

3

bunch

4

hollow fiber

5

first flow space

6

housing

7

inner space

8th

second flow space

9

potting compound

10

Center longitudinal axis (housing 2 )

11a

cap

11b

cap

12a

spigot

12b

spigot

13a

spigot

13b

spigot

14

ring seal

15

ring seal

16

Fit means

16a

extension

16b

free end (positive locking agent 16 / Extension 16a )

17

perforation

18

wall element

19

attachment

19a

body

20

orthogonal

21

Just

"Α"

Inclination angle (extension 16a )

Claims (15)

Hollow-fiber membrane filtration device ( 1 ) for body fluids, with a bundle ( 3 ) Hollow fibers ( 4 ) and one along the bundle ( 3 ) Hollow fiber extending housing ( 2 ) with a housing wall ( 6 ), which housing ( 2 ) an interior ( 7 ), in which the bundle ( 3 ) Hollow fibers ( 4 ) is arranged, the bundle ( 3 ) Hollow fibers ( 4 ) at both ends into a potting compound ( 9 ) and wherein the housing ( 2 ) on the inside at least one positive locking means ( 16 ) with a free end ( 16b ), which positive locking means ( 16 ) of the potting compound ( 9 ) Is at least partially enclosed, characterized in that the (at least one positive-locking means 16 ) by two or more, in the circumferential direction of the housing ( 2 ) seen spaced apart and at one end to the housing wall ( 6 ) connected extensions ( 16a ) is formed, each starting from an imaginary, the connection area of the relevant extension ( 16a ) to the housing wall ( 6 ) enforcing orthogonal ( 20 ) on a central longitudinal axis ( 10 ) of the housing ( 2 ) by a defined angle of inclination "α" in the interior of the housing ( 2 ) into one or the other end of the filtration device ( 1 ) are inclined downwards. Hollow-fiber membrane filtration device ( 1 ) according to claim 1, characterized in that the at least one positive locking means ( 16 ) in one piece with the housing ( 2 ) is trained. Hollow-fiber membrane filtration device ( 1 ) according to claim 1, characterized in that the at least one positive locking means ( 16 ) by at least one on the housing wall ( 6 ) of the housing ( 2 ) attached attachment ( 19 ) with two or more, in the circumferential direction of the housing ( 2 ) viewed from each other spaced extensions ( 16a ) is formed. Hollow-fiber membrane filtration device ( 1 ) according to claim 3, characterized in that the at least one attachment ( 19 ) is formed in one, two or more parts. Hollow-fiber membrane filtration device ( 1 ) according to one of claims 1 to 4, characterized in that the extensions ( 16a ) of the at least one positive locking means ( 16 ) at least in its connection region to the housing wall ( 6 ) are resilient. Hollow-fiber membrane filtration device ( 1 ) According to one of claims 1 to 5, characterized in that the angle of inclination "α" (between the said orthogonal 20 ) and an imaginary line ( 21 ) is formed which straight ( 21 ) on the one hand in the connection area of the relevant extension ( 16a ) on the housing wall ( 6 ) the orthogonal ( 20 ) and on the other hand, the resulting intersection with one of the housing ( 6 ) nearest point at the free end ( 16b ) of the extension ( 16a ) connects. Hollow-fiber membrane filtration device ( 1 ) according to one of claims 1 to 6, characterized in that the angle of inclination "α" starting from the orthogonal ( 20 ) according to the relation 0 ° <| α | <90 ° is selected. Hollow-fiber membrane filtration device ( 1 ) according to claim 7, characterized in that the angle of inclination "α" starting from the orthogonal ( 20 ) is preferably selected from a range of ± 10 ° to ± 80 °, more preferably selected from a range of ± 40 ° to ± 70 °, even more preferably from a range of ± 50 ° to ± 65 °. Hollow-fiber membrane filtration device ( 1 ) according to one of claims 1 to 8, characterized in that the connection areas of the extensions ( 16a ) of the respective positive locking means ( 16 ) in a common, orthogonal to said central longitudinal axis ( 10 ) of the housing ( 2 ) are arranged aligned first level. Hollow-fiber membrane filtration device ( 1 ) according to one of claims 1 to 8, characterized in that the connection areas of a first part of the extensions ( 16a ) of the respective positive locking means ( 16 ) in an orthogonal to said central longitudinal axis ( 10 ) of the housing ( 2 ) aligned first level and the terminal portions of at least a second part of said extensions ( 16a ) are arranged in a second plane parallel to the first plane. Hollow-fiber membrane filtration device ( 1 ) According to one of claims 1 to 10, characterized in that either all extensions ( 16a ) of the respective positive locking means ( 16 ) to one or the other end of the filtration device ( 1 ) are inclined or that extensions ( 16a ) of the respective positive locking means ( 16 ) changing regularly or irregularly to one or the other end of the filtering device ( 1 ) are inclined. Hollow-fiber membrane filtration device ( 1 ) according to one of claims 1 to 11, characterized in that at least one of the extensions ( 16a ) at least one opening ( 17 ), a recess, a bead-like shape and / or a bend at the free end ( 16b ) of the extension ( 16a ) having. Hollow-fiber membrane filtration device ( 1 ) according to one of claims 1 to 12, characterized in that the spacing between in the circumferential direction of the housing ( 2 ) seen adjacent extensions ( 16a ) by at least partially the relevant extensions ( 16a ) connecting elastic wall element ( 18 ) is taken, the elasticity of the wall element ( 18 ) greater the elasticity of the extensions ( 16a ). Hollow-fiber membrane filtration device ( 1 ) according to one of claims 1 to 13, characterized in that the housing ( 2 ) with extensions ( 16a ) or the housing ( 2 ) together with the at least one attachment ( 19 ) with extensions ( 16a ) consists of a material which does not have an adhesive bond with the potting compound ( 9 ) received. Process for producing a hollow fiber membrane filtration device ( 1 ) according to one of claims 1 to 14, characterized by the following steps: a) provision of a housing ( 2 ), the two ends on the inside at least one positive locking means ( 16 ) with a free end ( 16b ), which positive locking means ( 16 ) by two or more, in the circumferential direction of the housing ( 2 ) seen spaced apart and at one end to the housing wall ( 6 ) connected extensions ( 16a ) is formed, each starting from an imaginary, the connection area of the relevant extension ( 16a ) to the housing wall ( 6 ) enforcing orthogonal ( 20 ) on a central longitudinal axis ( 10 ) of the housing ( 2 ) by a defined angle of inclination "α" in the interior of the housing ( 2 ) into one or the other end of the filtration device ( 1 b) arrangement of a bundle ( 3 ) Hollow fibers ( 4 ) within the housing ( 2 ) such that the ends of the bundle ( 3 ) Hollow fibers ( 4 ) of the extensions ( 16a ) of the associated at least one positive locking means ( 16 ) c) at both ends of the housing ( 2 ) Introducing a potting compound ( 9 ) in the housing ( 2 ) such that on the one hand the ends of the bundle ( 3 ) Hollow fibers ( 4 ) of the potting compound ( 9 ) and on the other hand the potting compound ( 9 ) the extensions ( 16a ) is at least partially enclosed, and d) after hardening of the potting compound ( 9 ) Opening the ends of the hollow fibers ( 4 ) by trimming the ends of the hollow fibers ( 4 ) transverse to the longitudinal extent of the same.

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