Medical Device with an Optional Hydrophobic Filter Membrane and a Corresponding Front Support Structure

Abstract

The present disclosure relates to a medical device, in particular a blood cassette, having a device body and having at least one fluid reception chamber for receiving at least one first medical fluid, in particular blood. The blood cassette can also have a hydrophobic filter device through which the fluid reception chamber is supplied with at least a second gaseous fluid, in particular air. The filter device comprises a filter membrane welded to the fluid reception chamber. The filter device also comprises a front support structure on or at front side, which is arranged for supporting the filter membrane.

Claims

1.-16. (canceled)

17. A medical device comprising: a fluid system for receiving a first medical fluid; a device body; and at least one hydrophobic filter device with a filter surface through which at least a second gaseous fluid may be supplied to the fluid system, wherein the filter device comprises: at least one filter membrane having a front side and a rear side; and a front support structure at the at the front side of the filter membrane, wherein the rear side of the filter membrane is welded to a section of the device body along a weld section, and wherein the front support structure is arranged to contact the weld section through a first contact section of the front support structure.

18. The device according to claim 17, wherein the front support structure comprises a second contact section, wherein the front support structure is arranged to contact a support section of the device body through the second contact section of the front structure.

19. The device according to claim 18, wherein the second contact section is welded to the support section of the device body.

20. The device according to claim 19, wherein the weld section is a circumferential or closed section.

21. The device according to claim 19, wherein the first contact section is a circumferential or closed section.

22. The device according to claim 18, wherein the second contact section is clamped with the support section of the device body.

23. The device according to claim 17, wherein the first contact section of the front support structure is made of a softer material than other sections of the front support structure.

24. The device according to claim 17, wherein the front support structure is made of exactly only one material.

25. The device according to claim 17, wherein the first contact section of the front support structure protrudes or extends beyond the weld section of the device body in at least one direction or protrudes or extends at one side of the weld section.

26. The device according to claim 17, wherein the first contact section of the front support structure is connected to sections of the front support structure in a releasable manner.

27. The device according to claim 17, wherein the first contact section of the front support structure differs in color from sections of the front support structure.

28. The device according to claim 17, wherein the front support structure comprises one or more openings having a maximum diameter or width of 0.7 mm.

29. The device according to claim 17, wherein the front support structure comprises one or more openings having a maximum diameter or width of 0.5 mm.

30. The device according to claim 17, wherein the front support structure comprises a second filter membrane.

31. The device according to claim 17, wherein the front structure is a second filter membrane.

32. The device according to claim 17, wherein the medical device is a blood cassette.

33. The device according to claim 17, wherein the first contact section of the front support structure comprises a section made or formed by melting or temporary liquefying material during manufacturing of the device.

34. The device according to claim 17, wherein the first contact section of the front support structure is a section made or formed by melting or temporary liquefying material during manufacturing of the device.

35. A method for manufacturing a medical device, the method comprising: providing a device body of a medical device with a fluid system for a first medical fluid; providing a filter device with a filter surface through which a second gaseous fluid may be supplied, wherein the filter device comprises at least one filter membrane having a rear side and a front side, wherein the rear side of the filter membrane is welded to a section of the device body along a weld section; providing a front support structure; arranging the front support structure on or at the device body on the front side of the filter membrane such that it contacts the weld section through a first contact section of the front support structure; and welding together the front support structure and the front side of the filter membrane.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0198] FIG. 1 is a top view of a detail or section of the medical device as described herein, exemplarily configured as a blood cassette;

[0199] FIG. 2 is a cross-sectional view of a blood cassette as described herein;

[0200] FIG. 3 is an enlarged detail of the blood cassette shown in FIG. 2, shown in a longitudinal sectional view and tilted by 90 relative to FIG. 2 and relative to an arrangement during use of the blood cassette;

[0201] FIG. 4a is a view of a front support structure with a first contact section;

[0202] FIG. 4b is an enlarged view of details of the front support structure which is shown in FIG. 4a;

[0203] FIG. 5a-5d are highly simplified views of details of the blood cassette as described herein in different, exemplary embodiments;

[0204] FIG. 6a-6c are views of sections of both the cassette body and the front support structure in different, exemplary embodiments of the blood cassette;

[0205] FIG. 7a-7d are views of different embodiments of the second contact section and of the support section of the blood cassette as described herein;

[0206] FIG. 8 is a view of a device as described herein with a second filter membrane which is provided instead of the front support structure;

[0207] FIG. 9 is, like in FIG. 8, a view of an embodiment with a second filter membrane;

[0208] FIG. 10 is a view of a further embodiment as described herein of the front support structure prior to a melting of sections thereof;

[0209] FIG. 11 is a view of a further embodiment as described herein of the front support structure after a melting of sections thereof; and

[0210] FIG. 11a is a view of an enlarged detail of FIG. 11.

DETAILED DESCRIPTION OF THE FIGURES

[0211] FIG. 1 shows a top view of a detail of a medical device as described herein, embodied as a blood cassette 200 according to an exemplary embodiment.

[0212] Although the medical device as described herein is herein exemplarily embodied as a blood cassette 200 and although it is being discussed or elaborated on in this regard, the medical device shall not be limited thereto. The medical device as described herein may by way of example be a tubing system, a tubing set or (a) part of each.

[0213] The blood cassette 200 comprises a cassette body 201. The blood cassette 200 further comprises, optionally, a cover element 229, herein a film. The cover element 229, if provided, covers the cassette body 201 at least partially, possibly at an entire side thereof. The cover element 229 is made of a softer material than the cassette body 201 for which reason the latter is referred to as hard part. The cover element 229 covers the cassette body 201 against an exterior or an atmosphere.

[0214] The cassette body 201 comprises a fluid reception chamber 1 as well as an optional fluid supply chamber 3.

[0215] During use, there is a first medical fluid 5 temporarily present in the fluid reception chamber 1 which fluid 5 fills the fluid reception chamber 1 in FIG. 1 up to a fluid level 7.

[0216] The fluid supply chamber 3 which optionally comprises a filter device, of which a filter membrane 9 as well as a likewise optional rear support structure 11 are shown in FIG. 1.

[0217] The rear support structure 11 comprises a drainage structure 13. The rear support structure 11 is connected to the cassette body 201, e.g. to the fluid supply chamber 3, with the aid of fixation devices 15, for example rivet connections, weld seams or the like.

[0218] A fluid connector 17 is connected to the rear support structure 11 of the filter device.

[0219] Through the fluid connector 17, a second fluid 19 is introduced into the fluid reception chamber 1. The second fluid may be used for treating the first fluid 5, for example by applying pressure.

[0220] As is shown in the FIG. 1, the fluid reception chamber 1 represents a lower region 21 and the fluid supply chamber 3 represents an upper region 23.

[0221] The section of the blood cassette 200 shown in FIG. 1 is arranged such that the front side of the filter membrane 9 is viewed. The filter membrane 9 is disposed with its side lying behind the drawing plane on the rear support structure 11. The latter is denoted as rear support structure because the rear side faces the filter membrane 9 or is disposed on the rear side of the filter membrane 9.

[0222] FIG. 2 shows a blood cassette 200 in a cross-sectional view. The blood cassette 200 is pressed with or to a treatment apparatus 300.

[0223] The lower region 21 forms the deeper region, i.e., the fluid reception chamber 1. The upper region 23 forms the shallower region, i.e., the fluid supply chamber 3.

[0224] As is shown by the double arrow in FIG. 2, a second fluid 19 is introduced into the fluid supply chamber 3 through a fluid connector 17.

[0225] The fluid supply chamber 3 optionally comprises, as represented in FIG. 2, the rear support structure 11 which is fastened to the fluid supply chamber 3 by means of a sealing connection 25, for example a welded or bonded connection.

[0226] On the rear support structure 11 the filter membrane 9 is disposed, with a front support structure 27 in turn being provided on the latter.

[0227] The cassette body 201 of the blood cassette 200 is covered at one side by a cover element 229, for example a film.

[0228] By means of or through the intermediary of a rubber mat 301 which may serve for transmitting force and/or movements by sensors or actors of the treatment apparatus 300 to the blood cassette 200 or chambers and/or passages thereof, the blood cassette 200 is pressed with the treatment apparatus 300.

[0229] The rubber mat 301 may have a resilience structure 33.

[0230] In order to introduce or remove the fluids present inside the fluid reception chamber 1, the fluid reception chamber 1 may be provided with a fluid connection 35 at its bottom side.

[0231] FIG. 3 shows an enlarged detail or section of the blood cassette 200 of FIG. 2. To be more precise, it shows the filter device in a longitudinal sectional view.

[0232] In comparison with the representation of FIG. 2, the filter device was tilted by 90 degrees, so that the fluid connector 17 is directed upwardly in the representation of FIG. 3.

[0233] The tilting serves a better representation. During use of the blood cassette 200 the filter device takes or maintains or keeps its position of FIG. 1.

[0234] The filter membrane 9 which exemplarily comprises a membrane layer and a third support layer (not represented) in the form of a woven, is disposed between the rear support structure 11 and the front support structure 27.

[0235] For a detailed description of the single components, reference is made to the above explanations or embodiments.

[0236] In order to establish the sealing connection between the rear support structure 11 and the filter membrane 9, an optional first ring zone or first ring region 37 is provided. In order to establish the connection between the filter membrane 9 and the front support structure 27, an optional second ring zone or second ring region 39 is provided.

[0237] The arrows I of FIG. 3 show or point towards the inside or central section of the filter membrane 9. They point from the edge of the filter membrane 9 towards the inside.

[0238] The reference numeral 9a designates the rear side of the filter membrane 9, the reference numeral 9b designates the front side of the filter membrane 9.

[0239] The filter membrane 9 may have a carrier fleece on its rear side 9a and/or on its front side 9b. A carrier fleece may be a woven, it may comprise a Teflon layer.

[0240] FIG. 4a shows the front support structure 27 with a first contact section 27a. The illustration of FIG. 4a corresponds to the view of the side of the front support structure 27 which in turn faces, during use, the front side 9b of the filter membrane 9. The front support structure 27 comprises openings 28 passing through it, which are explained below with reference to FIG. 4b.

[0241] As is exemplarily shown in FIG. 4a, the first contact section 27a may be made of another or different material than the remaining sections or sections of the front support structure 27. For example, the first contact section 27a may be made of or may comprise silicon and may optionally be inserted for example as an O-ring into a groove or into a slot of the front support structure 27. Hence, the front support structure 27 may be substantially made of comparatively favorable or low-priced and harder material. At the same time, its first contact section 27a may be made of a softer material which may, although more expensive when compared to the harder material, advantageously cause no damage, unlike the harder material, when the first contact section 27a contacts the filter membrane 9 and when the front support structure 27 is being pressed against the filter membrane 9.

[0242] The first contact section 27a may, unlike what is shown in FIG. 4a, alternatively be made of the same material as the remaining sections or other sections of the front support structure 27. For example, the entire front support structure 27 including the first contact section 27a may be made of or may consist of silicon. This offers production advantages at rather higher material cost, as silicon is not a cost-effective material.

[0243] Some aspects as described herein encompass further embodiments by which, unlike the illustration of FIG. 4a, all sections of the front support structure 27 are made of, or consist of, a material, which material is not silicon. In this way, the front support structure 27 may be manufactured at low cost. The desired low hardness of the front support structure 27 is achieved when or upon connecting the front support structure 27 to the cassette body 201 during welding and due to welding the front support structure 27 in the area of the first contact section 27a to the cassette body 201.

[0244] FIG. 4b shows an enlarged detail of the front support structure 27 of FIG. 4a.

[0245] Openings 28 are shown, which make the front support structure 27 permeable for fluid which also can flow through the filter membrane 9. The permeability of the front support structure 27 for the fluid may optionally be rendered possible alone by the openings 28 as in the present example.

[0246] The diameter of (all or many of) the openings 28 comprises preferably a maximum of 0.7 mm, preferably not more than 0.5 mm. If the openings 28 are configured as slots, the previous measurements or dimensions apply analogously for the width of the slots.

[0247] FIG. 5a shows a schematically highly simplified detail of an exemplary embodiment of the blood cassette 200 having the cassette body 201 (as in FIGS. 5b to 5d shown in 180 side rotation relative to its illustration in FIG. 3), a filter membrane 9, a front support structure 27 and a rubber mat 301. The rubber mat 301 is part of a blood treatment apparatus 300, not shown in FIG. 5a, into which the blood cassette 200 is received.

[0248] The filter membrane 9 is welded to the cassette body 201 along a weld section 203. The weld section 203 may be circumferentially closed. This is not seen in FIG. 5a due to the cut illustration of this figure. The weld section 203 may be understood as the first ring region 37, see FIG. 2.

[0249] The front support structure 27 rests with a first contact section 27a at least partially or in-section on the weld section 203 or contacts the latter.

[0250] Preferably, the first contact section 27a extends or stands over the weld section 203 towards a direction I, i.e. towards the central section of the front support structure 27 or the filter membrane 9. This is shown and explained further in an enlarged view in FIG. 5d.

[0251] In the example of FIG. 5a, the front support structure 27 optionally comprises burls or protrusions 27b which preferably protrude or rise from the side of the front support structure 27 on which the front support structure 27 of the filter membrane 9 rests or with which it faces the filter membrane 9.

[0252] The burls or protrusions 27b are arranged on the edge side and/or in a middle area of the front support structure 27. They comprise slots in between so that a gas exchange or flow through said slots is rendered possible.

[0253] In the example of FIG. 5a the front support structure 27 comprises one or several burls or protrusions 27c, which preferably protrude from the side of the front support structure 27 which lies opposite to the side of the front support structure 27 which faces the filter membrane.

[0254] The rubber mat 301 further shown in FIG. 5a presses on the burls 27c of the front support structure 27.

[0255] The burls or protrusions 27c protrude preferably to a pre-determined extent in direction D. The direction D is perpendicular to the main extension plane of the filter membrane 9 and/or perpendicular to the main extension plane of the front support structure 27. This extent may be pre-determined such that the end sides 27c reach the rubber mat 301. This extent may be pre-determined such that the end sides 27c reach to a level N at which the cassette body 201 is covered in direction D with a film which is not shown in FIG. 5a.

[0256] In the example of FIG. 5a, the front support structure 27 optionally comprises a second contact section 27d. The second contact section 27d rests on a support section 204. The support section 204 may be configured as a protrusion or edge of the cassette body 201.

[0257] The support section 204 and/or the second contact section 27d may be circumferentially closed. This is not seen in FIG. 5c due to the cut illustration of this figure.

[0258] The first contact section 27a is disposed, with respect to the direction I, further inside than the second contact section 27d.

[0259] FIG. 5b shows a schematically highly simplified detail of the blood cassette 200 again in a further exemplary embodiment having the cassette body 201, a filter membrane 9, a front support structure 27 and a flanging or a flange edge 205. The flange edge 205 serves the clamping of the front support structure 27 at the cassette body 201 and in particular the pressing between the first contact section 27a and the weld section 203.

[0260] FIG. 5c shows a schematically highly simplified detail of the blood cassette 200 again in a further exemplary embodiment having the cassette body 201, a filter membrane 9, a front support structure 27 and a weld connection between the second contact section 27d of the front support structure 27 and the support section 204 of the cassette body 201.

[0261] The weld connection between the second contact section 27d and the support section 204 may be circumferentially closed. This is not seen in FIG. 5c due to the cut illustration of this figure.

[0262] FIG. 5d shows in an enlarged illustration that the first contact section 27a contacts or touches the weld section 203 as well as parts of the weld seam 203a, by means of which weld seam 203a the first contact section 27a contacts or is connected to the weld section 203.

[0263] It is also seen that the first contact section 27a comprises a section 203b which extends or stands over the weld section 203 inherein exemplarily exactly one direction I. The latter is an optional feature already shown in FIG. 5a to FIG. 5c.

[0264] A free space between the burls or protrusions 27b of the front support structure 27 on one hand and the filter membrane 9 on the other hand should not exceed 0.5 mm, preferably 0.3 mm. This space is indicated in FIG. 5d by double arrow. If it is larger than indicated supra, the filter membrane 9 may be too strongly bent before it comes to lie on the burls or protrusions 27b of the front support structure 27. A result thereof could be an undesirable high mechanical stress.

[0265] FIGS. 6a to 6c show sections of both the cassette body 201 and the front support structure 27 in diverse embodiments of the blood cassette 200.

[0266] The filter membrane 9 is not shown in FIGS. 6a to 6c, wherefore the weld section 203 cannot be shown in a welded state in these figures either.

[0267] The second contact section 27d is embodied in FIG. 6a as a closed surface which plane is or extends parallel to a main extension plane of the filter membrane 9, which is not shown, or to the main extension plane of the front support structure 27, like in the example shown in FIG. 5a.

[0268] A preferably likewise closed collar or edge 27e, whose inner and/or outer side may be perpendicular to the closed surface of the second contact section 27d, protrudes or rises on an inner side (left in FIG. 6a, see the arrow I). The edge 27e may be considered as a centering aid when inserting the front support structure 27 into the cassette body 201. It may serve when holding the front support structure 27, while the latter is being welded to the cassette body 201.

[0269] Although the edge 27e in FIG. 6a rests on an inner side of the second contact section 27d, it is intended to also alternatively provide it on the outer side of the second contact section 27d.

[0270] In FIG. 6b, the second contact section 27d and the protruding edge 27e merge into each other; the second contact section 27d may be considered as an end section of the protruding edge 27e.

[0271] In FIG. 6c, the second contact section 27d and the support section 204 of the cassette body 201 shown in a cross section in FIG. 6c are not flat, but curved, triangle or polygonal. This may support a centering effect. Moreover, an area or surface advantageously rises or elevates (ceteris paribus); said area being available for a contact between contact section 27d and the support section 204, e.g. for a welding. The aforementioned advantages may also be achieved when only the second contact section 27d or the support section 204 of the cassette body, but not both, are formed as described supra. Examples thereof are found in the following figures.

[0272] FIGS. 7a to 7d show different embodiments of the second contact section 27d and the support section 204 of the blood cassette 200.

[0273] FIG. 7a and FIG. 7b show embodiments which correspond to or resemble the embodiment according to FIG. 6c.

[0274] FIG. 7c shows an embodiment which corresponds to or resembles the embodiment according to FIG. 6a.

[0275] FIG. 7d shows an embodiment which corresponds to a combination of the embodiments according to FIGS. 6b and 6c.

[0276] FIGS. 7b and 7c thereby show embodiments which are particularly suitable in the light of shrinking during welding.

[0277] FIG. 8 shows a second filter membrane 10 which is provided instead of or in addition to the support structure 27.

[0278] The filter membrane 9, which in some exemplary embodiments could be referred to also as first filter membrane for better distinction, comprises a weld section or a welding 9c by means of which it is connected to a second filter membrane 10.

[0279] The second filter membrane 10 may be configured as the filter membrane 9 with regard to the features which contribute to filtering. This is optional, i.e. not necessarily required.

[0280] FIG. 9 shows as FIG. 8 a second filter membrane 10 which is provided instead of or in addition to the front support structure 27.

[0281] Both the filter membrane 9 and the second filter membrane 10 are divided into or comprise each a carrier fleece 9d or 10d, respectively and a Teflon layer or coating 9e or 10e, respectively.

[0282] Thereby, the filter membrane 9 and the second filter membrane 10 are arranged such that their carrier fleece 9d and 10d face each other, respectively. The Teflon layers 9e and 10e rest on the side of the carrier fleece 9d or 10d, respectively which faces away from the other filter membrane 10 or 9, respectively. In other words, the Teflon layers 9e or 10e thus point towards the outside, respectively.

[0283] In addition to the welding 9c of the filter membrane 9 with the second filter membrane 10 and the weld section 203 which are both known from FIG. 8, further two optional weld sections 9f and 10f are shown in FIG. 10.

[0284] Weld seam section 9f connects the carrier fleece 9d to the Teflon layer 9e by means of welding. Weld seam section 10f connects the carrier fleece 10d to the Teflon layer 10e by means of welding.

[0285] Weld seam section 9f may be provided in a closed manner like weld seam section 10f.

[0286] The Teflon layer 9e or 10e may each be made of, or comprise, PTFE (Polytetrafluoroethylene) or ePTFE (expanded Polytetrafluoroethylene).

[0287] FIG. 10 shows a further embodiment of the front support structure 27. This front support structure 27 comprises a profiled structure 29 in its area facing the weld section 203. The profiling 29 may be directed to the interior of the support structure 27 perpendicularly or almost perpendicularly or may extend such that channels are formed between the raised profiles. Such profiling 29 (combination between raised structures on the one side and channels on the other) may effect that when melting the structure for fastening the filter membrane to or on the front support structure 27, the material does not penetrate or only slightly penetrates into the central area of the filter membrane, but predominantly spreads or extends into or within the channel areas.

[0288] This is schematically shown in FIG. 11, where the material of the raised structures (shaded area of FIG. 10) extends into or within the area of the channels. The embodiment of FIG. 11 of the front support structure 27 may also be achievable by at least a partial melting of the raised portions of the front support structure 27 of FIG. 10. With that, the profiling 29 may at least be partially recognizable in the melted profiling 29b. The front support structure 27 may, deviating from the illustration of FIG. 11, be also designed as parallelogram.

[0289] The profiling 29 may be provided in a closed manner in the front support structure 27. This front support structure 27 may be designed as one-piece or may consist of one material. It has become evident that this embodiment may be suitable, even without additional softer support elements, to support the filter membrane which is sterilized by rays or e-beam so that a delamination of the filter membrane can be avoided.

[0290] Even though the following features are described with respect to the embodiment of FIG. 11, they may however be realized in all other embodiments as described herein as well. The front support structure 27 may comprise openings 28. These may be arranged in recesses 30 such that burls or protrusions 27b may be flatly formed between the openings 28. In the area of the openings 28, the front support structure 27 may also be formed thinner than in other areas. The principle is shown in FIG. 11 in the encircled areas in a front cut oblique view. Thus, the front support structure 27 may comprise in addition to the flat burls or protrusions 27b, which face the filter membrane, a profiling 31 on the side which faces away from the filter membrane. The thinner design of the support structure 27 in the area of the openings may allow gas to pass through easier (lower flow resistance); the additional profiling 31 may effect a stabilization by or in the form of higher bending strength.

[0291] All of the front support structures 27 and blood cassette bodies described above may comprise, or may consist of, polypropylene.

[0292] FIG. 11a shows an enlarged detail of FIG. 11.

LIST OF REFERENCE NUMERALS

[0293] 1 fluid reception chamber [0294] 3 fluid supply chamber [0295] 5 medical fluid [0296] 7 fluid level [0297] 9 filter membrane [0298] 9a rear side of the filter membrane [0299] 9b front side of the filter membrane [0300] 9c welding with a second filter membrane [0301] 9d carrier fleece [0302] 9e Teflon layer or coating [0303] 9f weld seam section [0304] 10 second filter membrane [0305] 10d fleece carrier [0306] 10e Teflon layer [0307] 10f weld seam section [0308] 11 rear support structure [0309] 11a burls or protrusions [0310] 13 drainage structure [0311] 15 fixation devices [0312] 17 fluid connector [0313] 19 second, gaseous fluid [0314] 21 lower region [0315] 23 upper region [0316] 25 sealing connection [0317] 27 front support structure [0318] 27a first contact section of the front support structure [0319] 27b burls or protrusions [0320] 27c burls or protrusions [0321] 27c end sides [0322] 27d second contact section [0323] 27e edge, collar [0324] 28 openings [0325] 29 profiling/profiled structure [0326] 29b melted profiling [0327] 30 recesses [0328] 31 profiling/profiled structure [0329] 33 resilience structure [0330] 35 fluid connection [0331] 200 blood cassette as an example of a medical device [0332] 201 cassette body or cassette main body, hard part [0333] 203 weld section [0334] 203a weld seam [0335] 203b section [0336] 204 support section [0337] 205 flanging or flange edge [0338] 229 cover element, film [0339] 300 blood treatment apparatus [0340] 301 rubber mat [0341] D direction [0342] I direction [0343] N level