JPH0140631B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hollow fiber artificial kidney device using a hollow fiber bundle of the type disclosed in US Pat. No. 3,228,876.

After being commercially introduced in the United States by Cordis Dow Corporation in the late 1960s, artificial kidneys using a single Mahon-type fiber bundle consisting of several thousand semipermeable cellulose or cellulose acetate hollow fibers were developed. The production of such kidneys, which are accepted and used throughout the world, has increased continuously since that time.

A commercial variant of such an artificial kidney has the general shape of a tube and shell heat exchanger similar to that shown in U.S. Pat. No. 3,228,877.
Approximately 4-10 inches long (10.2-25.4cm), diameter 1.5-
They typically range from 4 inch (3.8 to 10.2 cm) shells and usually contain more than 5,000 but fewer than 25,000 individual hollow fibers. The shell is divided into two blood chambers, which are separated by an intervening dialysate chamber, within which are hollow semipermeable fibers that allow blood to flow inside them. are carried, and their outer surfaces are continuously immersed in dialysate. The fibers are fixed together in tube sheets of solidified resin, and the tube sheets are present at each end of the fibers and serve to seal the blood chamber from the intervening dialysate chamber. The majority of artificial kidneys of this type have used cylindrical dialysate chambers integrally attached to the end blood chambers, each blood chamber having a larger diameter than the dialysate chambers, these being e.g. , US patent
3228876, 3228877, and especially 3882024 shown in FIG. Tubesheets are typically made by centrifugally casting a castable synthetic resin around the fibers and simultaneously placing those fibers within the shell in such a way that the solidified tubesheets form the cylindrical shape of the enlarged blood chamber portion of the shell. Place it in This type of widely used fiber potting or centrifugal casting method is
Disclosed in US Pat. No. 3,442,002 and US Pat. No. 3,492,698. Other possible methods are shown in US Pat. No. 3,772,695 and US Pat. No. 3,755,034.

One inherent advantage of the method of centrifugal casting the support tube sheet directly into the shell of the artificial kidney is that the tube sheet automatically acts as a separation barrier between the dialysate chamber and the blood chamber. Moreover, this separation barrier simultaneously forms a fluid-tight seal between the dialysate chamber and the blood chamber, which seal is free from contact between the surface of the inner wall of the shell and the surface of the outer wall of the tube sheet at its rim. arise. Ideally,
The desired seal results from adhesion between the selected castable resin and the shell as the resin of the tube sheet solidifies within the shell. A large number of artificial kidneys have been successfully produced and used in commercial manufacture by this method. However, while the hollow fibers are fitted together in the tube sheet and bonded together, the connections between the shell and the tube sheet under the varying temperature and pressure conditions encountered when the artificial kidney is transported and used for its intended purpose. Care must be taken to select materials for shells, tube sheets and hollow fibers that maintain the necessary fluid-tight seal. The problems inherent in maintaining these practically important seals have been extensively studied. Epoxy type tube sheet compositions are disclosed in U.S. Patent Nos. 3,619,459 and 3,703,962.
was explored and clarified in Suitable permselective fibers are disclosed in U.S. Pat. No. 3,423,491, while polyurethane-based tube sheet compositions are disclosed in U.S. Pat.
3962094.

Despite the above research efforts, the peripheral dimensions and uniformity of those dimensions for individual elements with respect to ensuring and maintaining adequate sealing to meet manufacturing standards or the actual conditions encountered during clinical use. Manufacturing difficulties remain due to tight tolerance requirements. The hollow fibers swell under conditions of use, i.e., internally wetted with blood, externally surrounded by tube sheet resin, and contacted with dialysate at the outer surface of the fibers proximate to the inner edge of the tube sheet surface. The problem of trends also exists. It has been observed that such expansion can destroy the seal between the shell and the rim of the tube sheet. Similarly,
Cleavage between the shell and tube sheet occurs due to uneven shrinkage of the inner shell wall and tube sheet resin during solidification, or partial cleavage occurs when the fibers are not positioned in the tube sheet with respect to the shell. , which may occur during testing or during use. Another emerging problem sometimes encountered in commercial manufacturing using centrifugal potting to produce tube sheets containing off-center fibers is the stagnation zone at the tube sheet surface that exposes the open fiber ends to the blood pool in the blood chamber. This is a blood clot problem. The blood chamber is usually formed by a cup-shaped member that is sealed against the flat surface of the tube sheet by a conventional circular O-ring, such as that shown in FIG. 4 of U.S. Pat. No. 3,882,024. When the hollow fibers extending through the tube sheet are off-center, stagnation zones occur in the unrounded or arcuate segments surrounded by the circular O-rings. In that segment,
The tube sheet surface is solid and there are no open ends of fibers available to accept blood;
And stagnation of blood at that location during a portion of a hemodialysis procedure can cause blood clots. In addition to unwanted loss of blood to the patient, such clots are difficult to remove or wash when backwashing the kidney in preparation for possible reuse, and if not removed, the kidney must be discarded. must not. The primary objective of the present invention is to provide an improved artificial kidney device that overcomes the aforementioned problem of tube sheet-shell seal failure.

A second important object of the present invention is to provide an improved artificial kidney device that eliminates blood clotting problems caused by off-center fibers in the tube sheet.

Another object of the invention is to centrifugally cast semipermeable hollow fibers into a castable resin, during which time the fibers are positioned in the shell of an artificial kidney, thereby positioning the fibers in the tube sheet. An artificial kidney device is provided which extends over the circumferential surface of its tube sheet and ensures exposure of open fiber ends in its transverse plane into the interior of the blood chamber.

The invention includes: axially outer end portions 64, 74, which define an opening;
shell 10 ending at 90; header 4 sealingly coupled to the outer end portion of the shell by a slip ring 92 and defining blood chamber 14;
4; a bundle of semi-permeable hollow fibers 27 disposed within the shell and extending from the shell to the opening; and a tube sheet 28 made of solidified casting resin that binds the fibers together; The tubular sheet has an inner portion 32 whose periphery is in sealing fit with the outer end portion 74 of the shell all around the opening, with an axially outer frustoconical portion 30 extending into the blood chamber 14 and containing fibers. an artificial kidney device comprising a tube sheet 28 whose outer open end terminates in an axially outer end surface 34 abutting the blood chamber 14; A fluid seal is achieved between the circumference 81 of the outer frustoconical portion 30 all the way around the tube seat; this header includes a skirt 84 surrounding the outer surface of the axially outer end portion 64 of the shell; and the axially outer end portions of the shell have a sealing portion in sealing engagement; the sealing portion forms a gas-tight engagement when the header is moved axially inwardly relative to the shell by means of a slip ring 92. The artificial kidney device is characterized in that: a conical surface 88 is formed;

The improved artificial kidney device includes a novel tube sheet element having a frustoconically shaped axially positioned fiber-containing portion surrounded by a fiber-free portion of the disc or rim; a chamber means or header overlying the frusto-conical portion in pressure-sealing relationship with a circumferential surface adjacent the flat outer end of the frusto-conical portion;
This forms a generally cup-shaped blood chamber.

The rim or disc portion of the tube seat preferably forms and maintains a fluid and gas tight seal during use between the outer rim surface of the tube seat and the inner wall of the shell. However, the blood chamber means or header includes axially inwardly extending portions integral with the blood chamber wall means, and a second or supporting hermetic seal is provided between these portions and the outer end surface of the shell. Formed by pressure-tight contact with them. These inwardly extending header sections isolate the internal tube sheet rim-shell seal from the blood chamber and air outside the shell, thereby preventing ingress into the dialysate chamber if the internal seal is breached. prevent.

The trapezoidal portion of the tube sheet contains centrally located hollow fibers, each of which generally forms a conical outer surface as it approaches its outer plane exposing the opening. In other words, in the frustoconical plane, there is no or substantially no rim of fiber-free solidified resin outside the profile on the outer surface of the fibers in the bundle.

The method of the present invention comprises an end mold mounted in a shell and having a novel combination of fiber positioning, frustoconical tube sheet forming means.
The method consists of centrifugally casting a settable castable resin into and around the ends of a bundle of hollow semi-permeable fibers surrounded by a mold.
While centrifugally casting the resin into and around the fibers,
The combination means that during casting and curing of the resin,
It positions and maintains the fibers regardless of the forces that tend to deflect the fiber bundle from the center as the resin penetrates between the fibers. After curing, the solidified tube sheet is cut transversely at approximately the juncture of the inner end of the locating portion and the outer end of the frustoconically shaped portion of the combination means. The resulting cut tube sheet is the improved element described above.

FIG. 1 shows the configuration of a hollow fiber type artificial kidney. The shell 10 is a dialysate chamber 12 located in the center.
and a pair of spaced apart blood chambers 14 attached to both ends thereof. Each blood chamber 14 terminates in an axially located blood port 16 which is covered by blood port cap means, generally designated 18,20. The dialysate chamber 12 has conventional inlet and outlet dialysate ports 22,2.
4 and surrounding a bundle, generally designated 26, of axially extending hollow semipermeable fibers of the type disclosed in U.S. Pat. No. 3,228,876. The number of fiber bundles 26 is several thousand, for example, 3000 to 30000, preferably 5000.
Contains ~25,000 individual fibers, which are of currently well-known types, e.g.
It can be either cellulose made by deacetylating cellulose acetate as taught in US Pat. Alternatively, the fibers may be cellulose acetate or other celluloses, or polyesters, or polyamides or other permselective fibers, such as U.S. Pat.
It can be as described in . Fibers are thin, capillary-sized, and typically have an inner diameter of approximately
Ranges from 150 to about 300 microns, with wall thickness of about 20
~50 microns range. Fiber 2 in bundle 26
7 extends into a pair of spaced apart tube sheets generally designated 28 . The tube sheet 28, as best seen in FIG. 5, is significantly different from tube sheets conventionally used in commercial hollow fiber artificial kidneys, and is one of the basic elements of the improved device. Configure. A typical tube sheet is centrifugally cast and then laterally cut to form a disc-shaped element that closes the outer end of the shell and
It ended in a plane, exposing the open ends of the fibers encapsulated in the solidified resin. The plane of the tube sheet is generally cut as the inner surface of the cup-shaped blood chamber,
The blood chamber had an O-ring placed around the central portion of the plane to expose the open fibers, and a cup-shaped header pressure sealed to the O-ring. Such prior art tube sheet and tube sheet 2
The key difference between 8 and 8 is that the inner part 32 of the conventional mold
The installation of a frustoconical section 30 attached to and integral therewith. This conical portion 30 extends axially outwardly from the inner portion 32 and terminates in a plane 34 across that surface and exposing the fibers 27 to the periphery of the frustoconical portion 30 shown in FIG.
The fibers 27 have a generally parallel or helical orientation within the dialysate chamber 12 and are slightly outward at gently tapered portions 36, 38 that connect the chamber 12 to the end blood chambers generally designated 40 and 42. spread in the direction. This is because during centrifugal casting of the tube sheet the fibers 27 are circumferentially constrained and the fibers take on a shape that follows the taper of the section 30, so that the profile or contour of the fibers 26 as shown in FIGS. As best shown in the figure, it is circular in plane 34.

The frustoconical portion 30, particularly its tapered outer surface, is used in combination with a blood chamber forming means, or header, generally designated 44, to form or define the blood cavity 14. This will be explained in detail following the explanation of the tube sheet 28.

The method of manufacturing the tube sheet 28 of the present invention may be better understood with reference to FIGS. 4 and 5. The fiber bundle 26 is initially formed in a conventional belt winder by known methods, such as that described in U.S. Pat. It is assembled into a shape and secured tightly by band means 46, which may be nylon or polypropylene tape, into a small diameter flat end section which is equally represented at both ends of the bundle (FIG. 4).

The shell 10 of the device is made using ordinary molding technology.
It is separately formed from a number of medically acceptable resins, such as clear polystyrene, impact-resistant polystyrene, polypropylene, polyacrylate, etc., and its fabrication is not part of the novel features of this invention. The shell 10 or jacket of the device and the enlarged end blood chambers 40, 42 are circular in cross-section as illustrated, but other shapes, such as lenticular, oval or other curved cross-sections, are possible. It should be understood that those capable of enclosing or accommodating a variety of tube sheet shapes are equally useful and suitable, such as those shown, for example, in U.S. Pat. No. 4,138,460, Figures 3 and 6-10.

The first step in the method of making tube sheet 28 is to insert bundle 26 into the elongated shell of FIG. 1 such that bands 46 extend outwardly from each outer edge of the shell at approximately equal distances. With the bundle 26 in place, in FIGS. 4 and 9, a combination positioning and frustoconical tube sheet forming means, indicated generally at 48, is moved axially over the band means 46 along the fibers 27, where the combination Means 48 is shown in FIG.
oriented at a distance sufficient to juxtapose the Each locating finger 50 includes an axially outwardly extending portion 52 joined to a radially inwardly extending portion 54, each of which has a plurality of fibers under elastic or radial compressive force. 27 and has an arc of sufficient width or circumference to cover and contact them. The combination means 48 are fabricated from a selected thickness of material, e.g. polyethylene, polypropylene, etc., to form fingers 50 which have sufficient deflection resistance to maintain the band 4 during the entire period of centrifugal casting.
6 maintains the outer circular contour generated by the collected outer wall surface of the fibers present in the outermost annular layer 45 of fibers. This contour remains the same as the inner circular contour defined by the inner edge 49 of finger 50, and
0 together encircle the circumference of the bundle 26 in the plane of the inner surface 53. The reason or necessity for fingers 50 will be discussed in further detail with respect to the centrifugal casting process.
However, the means 48 is a disposable element or means, which functions during centrifugal casting and which is intended to be disposed of after transversely cutting the fiber and exposing the fiber ends. Should be observed.

The mating means 48 also includes a radially outwardly extending tapered portion 56 which extends axially inwardly from the joining means 57 with the axially inner end of the portion 52 of the finger 50. The axial length of the taper 56 determines the length of the trapezoid of the cone cast against it and thus the tube sheet 2
Determine the length of the truncated cone section of 8. This length can be varied as needed for different sizes of making equipment. The length is not critical, but the angle is from about 8° to about 32°, preferably from about 15° to about 25°, from a diametric plane that passes vertically through the shell of the device when the device is oriented vertically. Said length must be chosen such that the diameter can be reduced from the rim or inner portion 32 of the tube sheet 28 to the diameter of the plane of the frustoconical portion 30. Means 48
includes flange means 58 commencing at the inner axial end of the taper 56 and extending radially outwardly and joined at its outer edge by a skirt 62 further extending axially inwardly. . Skirt 60, 62
has an inner diameter that is substantially the same as the diameter of the outer end surface 64 of the shell.

The final assembly of the combination means 48 on the fiber bundle prepared for centrifugal casting consists of the skirt 60,
62 around the outer end surface of the shell, thereby defining the desired frustoconical cavity around the fibers 27.

When the combination means 48 is in place as described above, the centrifugal casting assembly is configured such that the inner tapered surface 66 of the mold 66 lies in surface contact with the outer wall surface of the taper 56 of the means 48 while the flange 58 of the end mold 66 This is completed by placing an end mold 66 around the means 48 so as to contact the support flange 59. In this position, the locating finger 50 and the directionally projecting band means 46 lie within the space within the axially outer end portion 70 of the end mold 66. The mold assembly is then placed in a conventional centrifugal casting machine,
For example, installed in the device of U.S. Patent No. 3,442,002,
and the selected resin, preferably US Pat. No. 3,962,094
The polyurethane resin of the type disclosed in
2 and 24 at the same time. The resulting centrifugal force propels the castable resin outwardly from the blood port 24 into the cavity defined by the inner surface of the axially outer end portion 64 and the frustoconical cavity extending axially outwardly therefrom. is defined by the inner wall of the taper 56 of the means 48 as previously described. The castable resin penetrates the spaces between the fibers 27, wets their outer surfaces, and solidifies the resulting axially inner end of the inner portion 32 of the tube sheet 28 and the frustoconical portion 30 during continued rotation.

Prior to this invention, U.S. Pat.
In centrifugal casting of tube sheets as disclosed in US Pat. It has been observed that there is a tendency for the band means 46 to float off the axis of the rotating device. An undesirable result is that the fibers 27 as a whole bundle are bent or moved to an off-axis position. When the casting resin solidifies, the fibers 27
remains in an off-axis position, and when the resulting tube sheet is cut transversely to expose the open ends of the fibers 27 at the outer end plane, the fibers are in an off-center position. Rotating the device in a vertical plane is better than rotating horizontally, but does not solve the problem. The off-center placement of the fibers in the plane of the tube sheet creates potential clotting problems in use and possible reuse, and its elimination has long been desired. According to the invention, centrifugal casting in a vertical or horizontal plane is possible when using various castable resins, including thermosetting or thermoplastic resins, when fingers 50 or equivalent means are in place during centrifugal casting. as long as the fiber bundle is surrounded by a tube sheet with the fibers positioned with respect to the longitudinal axis of the shell. The resulting improvements in the precision of the uniformity of fiber distribution and the precision of the axial positioning of the fibers when using the method of the present invention are particularly beneficial in the novel frustoconical tube sheets produced thereby.

Due to the pressure on the outer fiber layer by the fingers 50 and the surface 49, the fibers 27 are pressed against the tube sheet 2.
The conical or outer surface of the frustoconical portion 30 of 8 generally tapers. This fiber orientation is such that all fibers are gathered and bonded within the contour defined by the outer axial end surface portions 49 of all fingers 50 at the planar inner surface 53;
FIG. 4 results specifically from locating the transverse cut of the fiber bundle 26 inwardly from the inner end surface 53 to the plane 34. A preferred location for the lateral cut is along or near the lateral plane located at the junction 57 of the axially outward end of the taper 56 and the axially inward end of the portion 52 of the finger 50. When the cutting plane is located along this plane, the fibers 27 provide uniformly spaced open ends which are connected to the conical wall surface and the peripheral junction of the plane 34 of the frustoconical tube sheet 28. 72, extending completely or substantially completely.

After completing the transverse cutting, the resulting device 10
includes a pair of spaced apart disc-conical tube sheets 28 at opposite ends of the elongated shell. Typically, tube sheet 28 provides a fluid-tight seal between the outer surface of the rim portion and the inner surface, such as shown at 74, of axially outer end portion 64, between the shell and the material used in making tube sheet 28. Formed by adhesion of

Novel double sealed non-disassembly device 10
The improved apparatus incorporating the novel tube sheet 28 therein and the method of providing a double seal will be further described with particular reference to FIGS. 5-9.

The blood chamber means or header 44 is shown in assembled relation to the tube seat 28 in FIG.
It is shown enlarged in FIG. The header 44 is in the shape of a stepped funnel and consists of a tubular blood port 16, shown in FIG. 7, with a smooth outer connecting surface that can be slightly tapered if desired. A wide conical portion 78 is integral with blood port 16 and extends axially inwardly and radially outwardly therefrom. Assemble the header as shown in Figure 5,
And when the shell is oriented vertically, the angle that the wide conical portion 78 makes with respect to the vertical axis of the shell is not critical. Such angles vary from about 30° to about 90°, preferably from about 50° to about 80°. At its inner extremity, the conical wide portion 78 has an inner surface 80
join with. Inner surface 80 extends axially inwardly and radially outwardly from portion 78 at an acute angle of about 8 DEG to about 32 DEG from a vertical plane passing through the axis of header 44 and shell when oriented vertically. inner surface 8
0, and the angle chosen for the taper of the frustoconical portion 30 should be the same or within 1 degree or less.

Before final assembly, the inner surface 80 of the header may differ from the angle of the frustoconical portion 30, but when assembled, the engagement surfaces assume the same angle and an elongated sealing surface 81 is formed. This seal ensures proper mating at the interface 72 and prevents destruction of the fine fibers 27 adjacent to the inner surface 80 while eliminating blood entrapment spaces at the sealing surface. As shown in FIG. 5, the elongated sealing surface 81 is approximately half the length of the inner surface 80 of the header 44, but the length of the sealing engagement can vary and is typically lateral after centrifugal casting. The direction will vary as a function of cutting position.

The inner surface 80 of the header 44 terminates at its inner end in a radially extending flange 82 that is joined to an axially inwardly extending skirt 84 . The outer surface of the skirt 84 tapers slightly outwardly in a range of about 2 DEG to about 10 DEG, preferably about 5 DEG from the vertical axial plane when the header and shell are oriented vertically. The inner surface of the skirt 84 has a circumferentially extending annular projection 8 that projects inwardly.
It has 6.

Header 44 is assembled overlying tube sheet 28 to achieve a secondary or support seal. The outer end wall of the shell includes an axially elongated outer end portion 64 terminating in a conical surface 88 on its outer surface. The conical surface 88 extends from the vertical axial plane when the shell is oriented vertically, e.g.
Extending slightly radially outwardly from the surface 90 and axially inwardly from the outer end portion 90 of the shell at an angle of 5° to about 15°. Annular projection 86 is forced axially along conical surface 88 as header 44 moves to its assembled position as shown in FIGS. 5 and 6, and the internal pressure of the dialysate chamber is reduced to its negative It is sufficiently pressed against its surface to form an airtight seal, even when operating at the lower limits of approximately minus 700 mm Hg below atmospheric pressure. This hermetic seal is formed between the inner portion 32 and the inner wall surface of the shell at its outer end, e.g.
4, prevents air from entering when the seal is broken.

To complete the assembly of the shell, tube sheet 28 and header 44, as shown in FIG. It is necessary to place it in the position shown in the figure and FIG. The slip ring 92 is
It is a ring having an opening 94 at its inner end defined by an axially elongated surface 96. slip ring 92
has an outer end opening 97 at its outer end and an inwardly projecting undercut internal means 98 adjacent thereto, the opening 97 being somewhat smaller than the opening 94, and the internal means 98 being used as required. The cap means 18 is adapted to snap-in engagement and lock in place to maintain sterility when the cap is removed. Enlarged annular shelf 100 of the second undercut
is provided between the internal means 98 and the internal portion 96. The annular shelf 100 applies pressure to the radially extending flange 82 of the header 44, causing the header 44 to move axially inwardly as the slip ring 92 moves to its final assembled position, as shown. Furthermore, the slip ring 92
applies radial pressure to skirt 84 and compressive force to annular projection 86 .
6 is deformed or flattened against the conical surface 88.

Double sealed assemblies as described above may be achieved by any suitable means such as heat sealing the header to the shell and optional ring 92 to the header and/or shell, or by adhesive bonding, or preferably by ultrasonic bonding. By welding, we convert it into a permanent, non-disassembly unit. Slip ring 92 is adapted for ultrasonic welding directly to axially outer end portion 64 in a manner described below. The inner portion 96 has a slight taper axially inwardly and radially outwardly from a slightly inward position to the inner means 98, for example about 3 DEG to 10 DEG.
The inner portion 96 includes a plurality of inwardly projecting circumferentially spaced tabs or weldments 102.
has. The axially inner or upper surface of tab 102 is parallel to the longitudinal axis of ring 92 and shell 10 when in the assembled position. The diameter of the upper surface of tab 102 is slightly less than the outer diameter of axially outer end portion 64, and when slip ring 92 is moved to the final assembled position shown in FIG. chosen so that there is a slight pressure interference between the two. Ultrasonic welding of tab 102 to the shell wall surface is performed while maintaining the slip ring under sufficient pressure applied axially inward, thereby permanently joining all parts together. Unit.

The shell 10 optionally includes a tamper-proof sterilization cap 18, details of which
It is shown in Figure 4. In summary, cap 18
is a snap-in removable twistway lid for the outer end of each blood port.
Removal of the cap 18 requires breaking the collapsible window portion, where removal can be visually detected, thus ensuring sterility up to the intended removal prior to clinical use.

The cap 18 is frustoconically shaped, and its shape blends continuously and smoothly into the external curved surface of the slip ring 92 and engages around the external wall surface of the blood port 16 from the inside. The axially inwardly projecting tortuous passageway means, FIGS. 10 and 11, includes a cap receiving cup wall 104 having a plurality of tortuous passage grooves 106 defining the passageways. The groove provides a passageway connecting the outside atmosphere and the interior of the device 10 via the blood port, while ensuring eradication of bacteria due to the multiple 180° turns 107 in the passageway.

The cap 18 has deformable or pressure deflectable means, FIGS. 13 and 14, and includes circumferentially spaced portions 110 of the outer cap wall 108, which are arranged as shown in FIGS. To,
It extends from about 25 DEG to about 50 DEG around the periphery of wall 108 and is bracketed and weakened by slot 112. Slots 112 extend axially outwardly from end 110 a short distance and are circumferentially spaced to define edges 114 of deformable portion 110 .

In the preferred cap construction, two oppositely disposed sections 110 are provided, each wall section 110 having a radially outwardly extending ridge or snap-in section 116, the sections 116 having a It is discontinuous around the remainder of the inner end wall section 118 which extends only between the slots 112 and interconnects the opposing sections 110. wall 118
The outer diameter of the cap 18 is approximately the same as the inner diameter of the ridge 98 of the slip ring 92, such that the cap 18 allows the stop-in ridge 116 to pass inwardly and to be located beneath the inner means 98 when the deforming pressure is released. A slight inward radial deformation of wall portion 110 sufficient to allow the ring 92 to easily snap into place.

The cap 18 has tamper-proof window means, generally designated 120, FIG. 13, at two 180° spaced locations in the upper end portion of the wall 108, as shown. The window 120 consists of two side-by-side panels 122, 124 that are interconnected by an axially extending slot 126.
and are separated from cap wall 108 by axially spaced slots 128, 130, 132 and 134. panel 122,
124 is preferably thinner than wall 108 and made from an easily stretchable and tearable material, such as low density polyethylene. The panel is thus weak enough to easily stretch or tear or tear, allowing the thumb and first finger to be inserted into the slot 12.
6, which allows the upper wall 136 to be gripped, and by pulling axially, the cap 20 can be separated from the slip ring 92.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the improved artificial kidney device of the present invention. 2 is a side view of the apparatus of FIG. 1; FIG. FIG. 3 is an exploded perspective view of the apparatus of FIG. 1, consisting of, from right to left, a shell surrounding an integral frustoconical tube seat, a blood chamber means or header, a slip ring sealing means and a sterile blood port cap means; The component parts are shown below. Fourth
The figure is an exploded perspective view of the parts used in centrifugal casting prior to assembly, including, from right to left, the fiber bundle-containing shell, the combination positioning and frustoconical tube sheet forming means, and the end mold. FIG. 5 is a vertical cross-sectional view of the device of FIG. 2 taken along line 5--5. 6 is an enlarged view of the sealing element shown for the bottom portion of FIG. 5; FIG. FIG. 7 is an enlarged cross-sectional view of the blood chamber means, or header, shown diagrammatically in FIG. 3; 8 is a partial vertical sectional view of the end mold shown schematically in FIG. 4; FIG. FIG. 9 is schematically shown in FIG.
9 is an enlarged cross-sectional view of the combined positioning and frustoconical mold liner oriented with respect to the end mold of FIG. 8 for placement therein prior to centrifugal casting; FIG. FIG. 10 is an enlarged view of the blood ostium cap shown in FIG. 5. Figure 11 shows the arrow 11 in Figure 10.
It is a drawing of the cap seen from the direction -11. FIG. 12 is an enlarged view of the wall portion of the cap of FIG. 5; FIG. 13 is a partial cross-sectional view of the cap of FIG. 5 showing the tamper-proof access window. FIG. 14 is a cross-section taken along line 14--14 of FIG. 13 showing deformable means that can facilitate assembly. DESCRIPTION OF SYMBOLS 10... Shell, 14... Blood chamber, 16... Blood port, 18... Cap means, 27... Semi-permeable hollow fiber, 28... Tube sheet, 30... truncated conical part, 32... Inner part , 38... Means for making fluid tight, 44... Header, 64... Axial outer end portion, 74... Axial outer end portion, 78...
...Second conical wide portion, 80...Inner surface, 82
... flange, 84 ... skirt, 86 ... integral annular projection, 88 ... conical surface, 90 ... axially outer end portion, 92 ... slip ring, 94 ...
...Inner end opening, 96... Tapered inner portion, 97... Outer end opening, 98... Internal means,
100... annular shelf, 102... means.

Claims (1)

[Claims] 1. Axial outer end portions 64, 7 defining the opening
Shell 10 terminating at 4,90; header 4 sealingly coupled to the outer end portion of the shell by a slip ring 92 and defining blood chamber 14;
4; a bundle of semi-permeable hollow fibers 27 disposed within the shell and extending from the shell to the opening; and a tube sheet 28 made of solidified casting resin that binds the fibers together; The tubular sheet has an inner portion 32 whose periphery is in sealing fit with the outer end portion 74 of the shell all around the opening, with an axially outer frustoconical portion 30 extending into the blood chamber 14 and containing fibers. an artificial kidney device comprising a tube sheet 28 whose outer open end terminates in an axially outer end surface 34 abutting the blood chamber 14; A fluid seal is achieved between the circumference 81 of the outer frustoconical portion 30 all the way around the tube seat; this header includes a skirt 84 surrounding the outer surface of the axially outer end portion 64 of the shell; and the axially outer end portions of the shell have a sealing portion in sealing engagement; the sealing portion forms a gas-tight engagement when the header is moved axially inwardly relative to the shell by means of a slip ring 92. An artificial kidney device comprising: a conical surface 88; 2. The device of claim 1, wherein the conical surface 88 is located on the outer surface of the outer end portion of the shell and tapers conically to the end of the outer end portion of the shell. 3. The sealing portion of the skirt 84 includes an integral annular projection 86 extending radially inwardly from the axially inner end of the skirt 84 and sealingly engages a conical surface 88 at the outer end portion of the shell. Apparatus according to claim 2. 4. A device according to any one of claims 1 to 3, wherein said means for pushing the header axially inwardly is a slip ring 92 surrounding said skirt 84 and pushing it radially inwardly. 5. The axially outer portion of the tube seat 28 is frustoconically shaped over at least the entire shaft portion and is in pressure engagement with a corresponding conically tapered portion of the inner surface of the header for the fluid seal. The device according to any one of the ranges 1 to 4. 6. Apparatus according to claim 5, wherein the radially outer fibers 27 in the frustoconical section 30 of the tube sheet conform to the contour of said frustoconical section 30. 7 A conical portion of the inner surface of the header is located on the inner surface 80 of the header, and this portion includes a flange 82 that extends radially outwardly from the radially outer periphery from which said skirt 84 extends axially inwardly.
Apparatus according to claim 5 or 6, ending with . 8 The slip ring 92 has an inner end opening that receives and surrounds the skirt 84 of the header, which opening provides a fluid tight seal between the inner surface 80 of the header and the frustoconical portion 30 of the tube seat. and for pressurizing said skirt radially inward to enhance the airtightness between the annular projection 86 on the skirt of the header and the conical surface 88 on the outer end portion of the shell;
The slip ring also has a portion axially abutting the radial flange 82 of the header, which portion holds the header axially inwardly to effectuate the airtight engagement between the sealing portions of the header and the shell. 8. The device of claim 7, further comprising means for securing said slip ring to an outer end portion of the shell. 9. The header 44 is funnel-shaped and includes a blood port 16 that opens into a second wide conical portion 78, which is approximately 30 mm from the long axis of the shell 10.
extending axially inwardly and radially from said blood port 16 at an angle of about 8 to 90 degrees and extending axially inwardly and radially from said blood port 16 at an angle of about 8 to 90 degrees.
9. A device according to claim 7 or 8, terminating in said inner surface 80 extending axially inwardly and radially outwardly from the longitudinal axis of said shell at an angle of 32°. 10 The slip ring 92 includes: (a) an outer end opening 97 having a smaller diameter than the inner end opening 94; (b) a portion of the slip ring 92 located inside the outer end opening 97 and contacting the radial flange 82 of the header; (c) an inwardly conically tapered inner portion 96 extending axially inwardly and radially outwardly from said shelf; and (d) means on said inner tapered portion 96. 102 in a radial direction of said skirt 84 on header 44 to deform and force an inwardly extending annular projection 86 on skirt 84 into sealing engagement with a conical surface 88 on an outer end portion of said shell. 10. The device of claim 9, comprising: means for contacting the outer surface. 11 Each blood port 16 is connected to the slip ring 9
11. The device according to claim 9 or 10, wherein the device is covered by a sterility maintaining cap means (18) removably fitted to the outer end portion of the device. 12. The means for removably engaging the cap means comprises an internal means 98 adjacent the outer end opening of the slip ring 92 and a mating means on the inner end of the cap means 18, both of which means 12. A device according to claim 11, wherein the two are fixedly adapted to each other.