AU529112B2 - Dialyzer assembly - Google Patents

Description

AN-A PALTENT APPLICATION FORM (CONVENTION) Form 4 V Jo COMMONWkEALTH OF AUSTRALIA'

All; i Patents Act 1952

CONVENTION APPLI -TIN FOR A-PATENT ~36179 10' fl we a) BAXTER TRAVENOL LABORATORIES, INC. ofa

s) faf f b ter n of 01canD

UNITED STATES OF AMERICA

hereby apply for the grant of 0 atent for an invention entitled "WaqE'tkoc CE li cttroLC= A-kr- aet> U A ibta C&1ot Inset title (C)"AC NP.tX

04 ft. a ft..

ftC a which is described in the accompanying complete specification. This application is a convention, a S application and is based on the application or applications for a patent or patents or similar protection a made in the following country or countries on the following date or dates: a ft. C ft. Insert in-d)U on o "jtcyIn 'ft ft ft a I slihfirst in No. 9.Z~y4.7 -1 a ft.. ft i(d) :4Y s1 No. 4..

in on No. in(d on No. a basic se a application. in on No. ft ft 3ft*

ft I j/Our address for service is care of ARTHUR S. CAVE CO., Patent and Trade Mark Attorneys, ft ft. ft I Alfred Street, Sydney, New South Wales, Australia 2000. ft Iner d. Dated this day of 19 79.. BAXT E ft a. LABORATORIES, INC., Re Is bifdIgRbon On

ft. 1t Ri~8 to ()By I.t s P atent Att 6,rn.e ft ace ksitloni.s

ARTHUR S. CAVE CO. Saal. if any.

To:

TheiCaumi -SsJlonr fatents, IQ. SIELY. F. .P.A.A. EAU- i9 AUSTRALIA qX ZO. fAtV NEYS A~E4

'PATh2NT DEOLARATION FORM (CONVNI FbDrmn 8 * COMP0fONWAL1'H OF AUSTRALIA PatentsAct 19S2

flICLARAIIN 1N SUPPORT OF ACONVENTION APPLICATION UNDE R PART XVI FOR APATENT 01R PATENT OF ADDITION To be signed by the applicant(s) or in the case of a Company, to beA signed by a person authorised by the Company 45 2)3i6& In support of the Convention application mader for a patent rran invention entitled (atnwtltea) A CASING AND METHOD OF MANUFACTURE of invention.

Wblnwat full OW~ GLRD.ON S.I.ELX., namne(s) of VPta tore-. declarant(s).

m~s(c) of o l.Ak declarnt(s). SYDNEY, SQtea.WJJ'U L~-

do solemnly and sincerely declare as follows:

(OR, IN THW.CASE OF AN APPLICATION BY A BODY CORPORATE.) 1. 1lam/we-re authorisedhby ris 1 nc the applicant for the patent to make this declaration .94. 4.4. 4. kacIxivi"oc 4.4. 14. 4. on its behalf. /1 4.4. 4.. 99 2. The basic application(s) as definied by Section 141 of the Act *I&/were made in the following ~kK country or countries on the following date(s) namely: 4.4. 4. a, *e Jd) on M~i~r 2.QaA15 No. (0.888,a.0071 4.4. by B tS.B nran Wll m J Schnell1 4. 4. 4. wafied. in A o aA .y No. ,4)4nmi dama 4. ttfuic by aer.t Bda .adW11a on No.(f) TiAo by nfful q aze the nt-eel inetrs f te Y feto referred to *f A (,!HERE A PERSON OTHER THAN THE INVENTOR IS THE APPLICANT) V. insertfull nuns(s) of Pj n~ V *4.

I) inol(s) In"Irt 1l) of Qi) -5 .1ritin...treet Pak ide....1.inas..raD.68 44111k aidrealm) of

Wta ti- u n f.fei 4/ jWIae the actual inventor(s) ,f the invention and the facts upon whc entitled to make the application are as folloivs: teCmayi 4. 4.

4. (klt-uthow (kc)B.,§axter .Travenol Laboratories,.Inc...is the- ass.igan ee .4.4.4.4.4. 4. 4. duevesstitle 9f frm4~dX~ .f tb AI !inv4?nti~n..f m. the said )1 110,Ios 4. The basic application(s) referred to in paragraph 2 of this Declaration woe/were the first ntiyl ,applications) made in a Convention country in respect of the invention the subject of the application.

Deslazed rt SYD~NEy 14 day 9f 19 79 1I~o: N.S.W.

7 fAMES G. SIELY.F .I.P.A.A. (Signature of Declarant)

(12) SITRALIAN PATENT ABRIDGMENT (19 AU (11) AU-B-45236/79 Y) "y

(54) ,METHOD OF MAKING A DIALYZER ASSEMBLY (71) BAXTER TRAVENOL LABORATORIES, INC. (21) 45236/79 529112 (22) 19.3.79 (24) 20.3.78 (31) 888071 (32) 20.3.78 (33) US 928477 27.7.78 US

(43) 27.9.79 (44) 26.5.83 (51) 2 A61M 1/03 BOlD 13/00 (72) BERT-iS. BODNAR AND WILLI'AM J. SCHNELL (74) CA (56) 37767/78 BOD1 A61M 53596/69 444697 87.4 13749/66 452461 28.8, 00.8, 70. 4, 83.1

(57) Preferably, the sealant may be provi'vd through the side apertures in the casing by attaching the outlet port of a hollow, elongatedmember as a p./ting boat) to the side apertu-4es of (known the casing, and placing thi& iquid sealant into the hollow, eloigated member yprior to 'spnning the casing. The outlet ports of the potting boat are preferably positioned at its respective ends. Claii 1. The method of potting the ends of a bundle of hollow fibers positioned in d casing, which comprises: inserting said bundle of hollow fibers into said casing through an open end thereof; &ealingly closing the ends of said casing by attaching casing closure member means to said casing; attaching opposed, side-mounted outlet ports of a hollow, elongated potting boat member to side aperatures positioned in fluid communication with said casing; placing curable liquid sealant into said hollow, elongated member; and spinning said casing ends about an axis of rotation extending through a central portion of said casing; whereby said liquid sealant migrates by the centrifugal force of

D /2

D1 18 2

16:68

Hollow tubular casing lOa contains a hollow fiber

bundle 12a in a manner similar to the previous embodiment,

with the ends of bundle 12a projecting from each end of

(11) AI-B-45,23679 -2-

sai,d spinning to the interior ends of said casing through said side apertures to pot the ends of the fiber bundle within the casing; and, after said liquid sealant has cured, removing said casing ends and cutting through said sealant and hollow fibers at each casing end to expose the bores of said hollow fibers.

i' X<

116:68/9

the previous embodiment. The urethane sealant 39a is added

to fill each of the sealing members 55 and preferably part

of members 16a so that the inner edge of the sealant is at

least substantially within sleeve 52. As shown in Figure 8,

AUSTRALIA 5291 12 PATENTS ACT 1952-1973

COMPLET§, SPECIFICATION

(ORIGINAL) 45 2364ri nNumer:FOR Ap-,lictil, OFFICE USE Appicaie~n umbr:Class Into Class Lodged:

Complete specification Lodged: Accepted: Published %;1

Priority: 4 Related Art:

TO BE COMPLETED BY APPLICANT

:Name of Applicant: BAXTER TRAVENOL LABORATORIES, INC.

-Address of Applicant: One Baxter Parkway, *so Deerfield, Illinois 60015, UNITED STATES OF AMERICA :Actual Inventor: BR .BDA n WILLIAM J. SCHNELL

A-ddress for/,siervice:C/_ ARTHUR S. CAVE CO., Trade Mark Patent *ttvrmacys,. 1 Alfred*Street, Sydney, New South Wales 2000, Australia Complete Specification for the invention entitled,-- 9,.Aso&C~D~fO OF BANUFAeTURSO

Trhe fo1Llow inq statem ~nt is a full description rnf this invention, including thte best me~hod of performing it known to me:-

SE

*so: eTI IA PSII 1C

-or4 0 DL

TArOffKM 'wi

Hollow diber dialyzers are a well-known and in-

creasingly popular form of dialyzer for use as artificial

kidneys, as well as other desired uses. One liquid for

dialysis, typically blood, passes through the bore of a

bundle of hollow, semi-permeable fibers, while a second dial-

ysis liquid flows through the bundle against the exterior

surfaces of the fibers.

Conventionally, as in U.S. Patent Nos. 3,492,698

c1u and 3,442,002, the hollow fiber bundles are placed in a Cl generally tubular casing, and the ends are potted within

thecasing to provide a seal. After cure of the potting he

C compound, the potted areas are sliced to expose the bores

of the fibers in the bundle, and exterior manifold members C are placed over te ends of the casing so that blood or

other liquid can be conveyed to the ends of the fibers at

one end of the casing, and collected from the other ends

of the fibers at the other end of the casing. ',d 00CC In the usual manufacturing techniques, the casing

is spun about an axis of rotation extending through the

cen er Of the casing, so as to place a centrifugal force

C Cn upon the potting compound at opposite ends of the casing 0, while potting compound is added through the ends, and as it

cures. The ends of the casing are typically sealed by a re

O temporar mechanical end seal of the centrifuge apparatus,

to prevent the loss of sealant out of the open ends of the

casing.

2

i i'

It has been found that it is difficult to seal

the potting compound since the open ends are under a sub-

stantial G-force from the centrifuge. Accordingly, some

leakage of sealant often takes place, even when expensive,

high-performance mechanical end seals are provided to the

centrifuge and apparatus. S The invention in one broad form comprises the

method of potting the ends of a bundle of hollow fibers

positioned in a casing, which comprises: inserting said

bundle of hollow fibers into said casing through an open

end thereof; sealiily closing the ends of said casing by

attaching casing closure member means to said casing;

attaching opposed, side-mounted outlet ports of a hollow,

elongated potting boat menber to side apertures positioned,

in fluid communication with said casing; placing curable

liquid sealant into said hollow, elongated member; and

spinning said casing ends about an axis of rotation

extending through a central portion of said casing; where-

by said liquid sealant migrates by the centrifugal force

of said spinning to the interior ends of said casing

through said side apertures to pot the ends of the fiber

bundle within the casing; and, after said liquid sealant

has cured, removing said casing ends and cutting through said

sealant and hollow fibers at each casing end to expose the

bores of said hollow fibers.

3

The claims defining the invention are as follows:

i. The method of potting the ends of a bundle of

MiRMIPTION OF THE INVENTION

In accordance with this invention, a method is

provided for potting the ends of a bun le of hollow fibers

a positioned in a usually tubular casing,: The fiber bundle is inserted intothe casing through an open end thereof.

SThen the end or ends of the casing are sealingly closed

4 with preferably rigid casing closure member means to effec- Ct. tively seal the casing ends, for example by solvent or ultra- Cq Lfb sonic sealing of the closures to the casing to integrally.

;"incorporate the closures and casing. Alternatively, the casing

ends and casing closure members may carry screw threads to that

the closure members may be screwed on the ends for sealing and

later removed.

After closing the casing ends with the closure members,

15 one spins the casing ends about an axis of rotation extending a.

through a central portion of the casing, while inserting cur-

.r able liquid sealant through side apertures in the casing. Accor-

dingly, the liquid sealant migrates by the centrifugal force of

the spinning to the interior ends of the casing, to pot the ends a

20 of he fiber bundle within the casing. After the liquid sealant 9a. is cred, one may cut through the closure member means, and

also the cured sealant and hollow fibers at each casing end, to

expose the bores of the hollow fibers. Alternatively, one may

simply remove the closure member means as described above and

I'S then cut the sealant and fibers.

Thereafter, manifold means may be conventionally

placed on each end of the casing to facilitate liquid flow through

the open bores of the fibers in the bundle.

Preferably, the sealant may be provided through the

4

-yw ji-l~~ side apertures in the casing by attaching the outlet port of a hollow, elongated member (known as a potting boat) to the side apertures of the casing, and placing the liquid sealant into the hollow, elongated member prior to spinning the casing. The outlet ports of the potting boat are pre- ferably positioned at its respective ends.

Accordingly, upon centrifugation as described

above, the sealant is driven to the respective ends of the

potting boat, and from there through the outlet ports and

side apertures into the casing, where it migrates radially

outwardly into the casing closure member means to surround

and seal the ends of the fiber bundle. This is done without

spilling, because the casing closure member means can provide

an absolute seal, greatly improved over any temporary seal

member carried by the centrifuge which has been previously S* used to pot the ends of a casing from the exterior, while at

the same time attepting to hold the sealant in position against a

the centrifugal force generated by the centrifuge.

SAfter the sealant has cured, the rigid casing clos-

S ure member means is then opened, and the potted bundle end may S.

be cut in a two-step process as follows: first, a circumfer- 0a0 ential channel or notch may be cut through the casing or casing *a

S* closure member, for example, by the use of a parting tool, to

expose the potted bundle underneath the generally rigid plas-

tic of the casing closure members. Alternatively, the casing closure member may be simply removed for example, by unscrewing

it. Thereafter, the potted bundle end may be conventionally

sliced with a precision meat slicer or the like, through the

cut circumferential channel or notch, or at its exposed end

where the closure member is removed, to provide a flat surface which includes the opened bores of the fibers in the bundle.

If desired, the rigid casing closure means may

comprise plastic cup-shaped members, each sealed at their

rims to an end of the tubular casing. A portion of each cup-shaped member adjacent the rim may be of relatively en-

r larged diameter, relative to thi tubular casing, to serve

t3 as a manifold means for side apertures in the casing,

,which in their ultimate use nay serve as the inlet and Uoutlet ports for one of the fluids o be dialyzed.

Each of the cup-shaped members may also define an

extended cylindrical portion, preferably of equal or greater

length than the enlarged diameter portion, positioned re-

motely from the rim and having a diameter of less than the

relatively enlarged-diameter portion. This segment of the cup-shaped member receives an end of the hollow fiber

bundle, and is filled with the potting compound. Brxcau~e S of its reduced diameter, the amount of potting compound

used is reduced over various prior art techniques.

Alternatively, the casing closure means may

p simply be separate end plates, attached to and sealing each

end of the casing after insertion of the fiber bundle. In

this case, the casing itself may be cut open after the centri-

fugation step.

Referring to the drawings, Figure 1 is an elevation-

al vi'w, shown in partially diagramatic form, of a hollow fiber bundle positioned in a casing and carried by a centrifuge in

accordance with this invention.

Figure 2 is a longitudinal sectional view of one

end of the casing and fiber bundle shown in Figure 1, also

6

:;8ars~irrr u~*~ikwWWWWWWWAR WWOWWW"' sthwing the sealant migrating from the potting boat to the respective ends of the casing.

Figure 3 is a view similar to Figure 2 showing

how the closure member means is cut through by cutting of

a circumferential channel about the closure member.

Figure 4 is a view similar to Figure 2 showing how the end portion of the closure member is removed and

C the potted ends of the fiber bundles are sliced.

f Figure 5 is a perspective view of a separate,

hollow tubular casing of this invention into which a fiber

bundle is placed, and a separately molded closure member,

which is adapted to be sealed to an end of the casing.

Figure 6 is a perspective view of the finished, cut tubular casing and a manifold member about to be attached

thereto.

"S Figure 7 is a plan view of an indexing carous l

for semi-automated mass production of potted hollow fiber bundles in casings, in accordance with this invention.

Figure 8 is an elevational view of the end of a

hollow fiber bundle in another embodiment of the casing and

associated cup-shaped casing closure member of this inven-

tion. **Figure 9 is a fragmentary elevational view of an end

of the casing and fiber bundle shown in Figure 8, showing how

"SI the projected potted fiber bundle end may be cut.

Figure 10 is a fragmentary perspective view of an end of the casing and fiber bundle shown in Figure 9 at the

completion of the cutting step.

77

45236n7

r-31 ,-34

ReOrring ,to Figures -1 through 6, a method and Cy1isd a~paratus fo~rassembling a potted, hollow fiber bundle which within a casing is disclosed. A central, hollow tubular 24, ha casing 10 is shown to be initially loaded with a hollow larged fiber bundle 12, which preferably may be made in 5 tioned danee wit-. h h 41eeleserez3 :_4t ed, et U.S. JT Patent appli-tie Ne. ?67,711, fiL~ld bLeray 44, 41977, Ifj repres r-by any &t~ter- desired technique for assembling fiber with o bundles. Hollow fiber bundle 12 is shown to be longer than disclo 1.0 "d4 central casing 10, so that it protrudes out of bottk ends of

the casing 10 by a predetermined length. It is also pre- 12. ferable for the ends of fiber bundle'12 to be surrounded

and secured with tape 14 prior to insertion of the bundle closur 4P

into casing 10, for ease of insertion and to pr~eVent disrup- sonic "a5 a.. 41' tion of the bundled array of fibers. assemb 4u 4 Thereafter, generally cup-shaped casing closure 4r centri 4I a .r members a I 16 are sealed onto the ends 18 of casing 10, to being surround and enclose tb fiber bundle 12 by ultrasonic Arms 2 welding or the like for a permanent, hermetic seal bond. 4.4

a As shown, the sealing cup member 16 defines a closed end made c *4

wall 20, which may be positioned to be slightly spaced its ou I.

from its associated end of the fiber b-undle 12. 22 as .4r 9.

44 4rr Also, in this embodiment, the cup-shaped closure may be 4 a* member means 16 carries side aperture member 12 as an inte- may be gral part thereof. apertL "25. 4e a Furthezcmore, a portion 24 of the cup-shaped seal- casin ing member 16 is of relatively enlarged diameter, relative

to tubui.ar casing 10, to serve as a manifold area for fluids 34 int passing into or out of side apertures 22. Another extended,

-8-

i /.cnn" I~n

Cyliadrical portion 26 of the cup-shaped sealing member 16,

which is preferably of equal or greatr length to sectipn

S24, has a diameter which is less than the relatively en-

larged diameter portion 24 and is, as stated before, posi-

tioned to receive an end of the hollow fiber bundle 12.

J The structure as shown in Figure 2 typically

0D represents the structure as it is at both ends of the casing, CO C with one end being omitted for purposes of simplicity of disclosure.

Inner flange 25 may be used to help center bundle

12.

After ,sealing of a cup-shaped, rigid casing

closure member means 16 at each end of casing 10, by ultra-

sonic welding or any other desired technique, the resulting

assembly is mounted on a centrifuge rotor 28, operated by

centrifuge 36, both of which may be of convention1al design,

being adapted to firmly hold casing 10 and its related parts.

Arms 29 of the rotor grip casing 10 and end members 16.

A hollow, elongated potting boat 30 which may be

•cQ made of thermoformed plastic or tho likc, is attached with

its outlet ports 32 positioned within side aperture members

22 as illustrated in Figure 2. Any desired retention means 9

may be used. For example, the end of each outlet port 32

may be slightly bulbous, as shown, for a friction fit within

aperture members 22, and the boat 30 may be attached to

casing4i0 by rubber bands 31,

The top of potting boat 30 defines an open aperture

34 into which liquid-curable sealant, for example polyurethane

9

IIIIIIYlk -YICT-. C~Y II~- IC~ 1IY-III~1II1IPI c~--n

Swa~ ay be iiasertet, typically while thecentrifuge is

in eperatiGj, This is after installation of casing 10 and

Sthe potting boat 30 on centrifuge rotor 28.

The centrifuge 36 spins casing 10 about an axis

of rotation h extendincS through the center of the casing.

SThe urethane sealant 39 is driven radially outwardly toward

both ends of the potting boat 30. From there, the sealant

Qq migrates through 6Utlet port 32 and side aperture member 22,

to continue'the flow radially outwardly along the upper

0L edge of sealing cup members 16, to).fill the remotely posi-

tioned portion 26 of the sealing cup member, surrounding and

enveloping the ends of fiber bundle 12. Typically, an amount

S of sealant is used sufficient to permit the filling of portion

S 26 of the sealing cup member up to about the level of flange

38, which defines the junction between portion 26 and portion

24 of the sealing cup member'.

As a result of this, less sealant is'used, while at

Sthe same time the bundle 12 is thoroughly potted at its ends,

and bonded to the interior of the casing assembly.

.0 After the seilant/4~ has sufficiently cured, cen- t A

trifuge 36 is stopped. Casing 10 and its related parts may

be removed from the centrifuge, and potting boat 30 may be

removed as well, for either reuse or discard as desired.

After the sealant is completely cured, the casing

:2 assembiy may be opened at its ends, typically by the initial

*S step of cutting a circumferential channel or notch 40 through

each closure member means, specifically in section 26 of the-

clesare member biap. This is as shown in Figure 3, and may

e iNaprigto fdsrd oeps ie

Eattde ard cl~nted sealant at the bottom ofnotch 40. There- af et,* a emmaesial meat slicer or equivalent machine may

be used to cat through groove 40 to sever the potted

bundle end and remove the ends of the casing assembly

As shown in Figure 4, several sequential slicing cuts may

be used as desired in order to obtain a smooth cut, in

which the maximum number of fibers in the bundle have open,

-exposed bores, and also to provide a smooth surface which

y" does not stimulate blood clotting.

Thereafter, a conventional manifold member 41 may

be added to each end. It is preferable for the side port

members 22 of thb casing to be parallel to each other, to

facilitate attachments to the potting boat

Referring to Figure 7, an industrial layout making

use of the apparatus and method of this invention is dis-

closed.

Carousel platform 42 carries a plurality of centri-

o fuges 36 in a 'series of stations for continuous and multiple

manufacture of potted, hollow fiber bundle casings on a semi-

automated basis. Each centrifuge station 36 is adapted for

practicing the present invention as described above.

Accordingly, as each centrifuge station 36 is in-

dexed to position 44 by rotational indexing "f the carousel

42 0 a predetermined schedule, it may be unloaded of its

proessed hollow fiber bundle, casing, and reloaded with a

mew casing andpotting boat. Then, the predetermined amount

of sealanta-is inserted into the potting boat after the cen--

trifige 3#6 is turning, and the' carousel platform index onward

to pore'set aot-her ce~trifuge 36 to work station 44, while.

tih~e ft-eosy-l1oaded centrifuge is rotatiorpally moved -away K>

from the station,44 for automatic'centrifugal processing for airy desired length of time.

Accotdingly, -one operator can, if desired, service,

all of the centrifuges on thecarouzel platferm 42, while the remaining centrifuges 36 operate until the allotted cure

g~times elapsed,,

C*4 Preferably, carousel platf~rm 42 is enclosed in a

kM housing 46, equipped with a vent pipe 4'8 to remove fumes, Ze-

sulti ng from the curing of the sealant.

Alaso, carousel. platform 42 may carry recirculating K 22 J) forced air heaters 50 to heat the holor fiber bunide casings

and their related members to a te~iperature w.lich is pre-

#4 ferably higher than that of t1 polyurethane sealant, prior

T;S to injecting of the polyureth L L, into the,/ casing I0 for pot-

ting. The urethane then 'tends to-bond first to the dialyzer

casirig wal,1 an then as it builds in volume, moves slowly,

irnwiaxdly to bond the fibers togethei,, providing an improved

overall se-al. Generally, ELtemFp-e3)ature of 130'P. is desir-

Z'D able, IC ~4 I Alternative'ly, a second operating station could' *4 KIll

be provided, for er~ample 1800 around from the first work 4 4 .0 station 44,, or any~other' arrang~xnent may be used as may be

I desirable.

Referring now to F'igures 8 through 4 em1badirnext of the invention of this application is disclosed whaicb may beietcli ticure and manufacturing tech-

aiqe to, the emblodiment described in Figures 2 through 7,

eow&pt ats is indicated below.

12

L i 1, 1

116:68LB/8

Hollow tubular casing 10a contains a hollow fiber

bundle 12a in a manner similar to the previous embodiment,

with the ends of bundle 12a projecting from each end of

casing lOa.

In this embodiment, side aperture member 22a may be carried by end member 16a, which is sealed to tubular C casing lOa, as in the previous embodiment. C C4 In distinction from the previous embodiment, end

member 16a defines a terminal sleeve member 52 which is

610 equipped with helical screw threads 54. The opposed end of

casing lOa and end member 16a may be of similar design to

that shown in Figure 8.

After insertion of fiber bundle 12a into tubular casing lOa a generally cup-shaped casing closure member

is provided at each end of end member 16a. Closure member

which carries mating helical screw threads 56 at its lip, may

S I be simply screwed onto eacn end of member 16a to provide a i* hermetic seal to the ends of casing 10a. The emplaced cup-

shaped casing closure member 55 is shown in phantom lines in

20 Figure 8. *8

Closure member 55 defines a diametrically disposed Sblade 57 across its outer end to facilitate the emplacement

and removal of closure 55 on and from casing end members 16a. t 10a and the respective closure members 16a, Casing

i at each end of casing 10a may be attached through side

r.y* apertures 22a to a potting boat 30 in a manner similar to that shown in Figure 1. The centrifuge is activated to cause the k ure'-hane sealant 39a to flow to the ends of casing 10a and

to cure in a manner analogous to that shown and described in the previous embodiment. The urethane sealant 39a is added to fill each of the sealing,members 55 and preferably part of members 16a so that the inner edge of the sealant is at least substantially within sleeve 52. As shown in Figure 8, the sealant is then cured to assume the outline of the inner Schamber of each cup-shaped casing closure member 55. If

C.0 desired, the apparatus of Figure 7 and the preferred methods CO q of potting described previously may be used. Aftet the potting and curing step has taken place,

the centrifugation process is terminated, and each of the

closure members 55 is removed by simple unscrewing of the

closure member from the threaded sleeve 52 on end members 16a.

Thereafter, the ends of fiber bundle 12a, potted with cured sealant 39a, are .cut off, preferably by means of a round

g knife 60 positioned adjacent each end of the casing S.

Preferably, the casing lOa may be placed within a rotatable

drum with its ends projecting, and then rotated about its

longitudinal axis while being brought into cutting contact

with a pair of knives 60, positioned to make the cut at

each end of casing 10a at the desired positions. Arrow 62

indicates the direction of rotation of casing 10a and its

associated parts.

The result of this step is to expose the bores of

the hollow fibers of bundle 12a in a flat end surface 64,

which comprises the ends of the fibers of btiidle 12a and

cured sealant, with surface 64 generally projecting slightly

outwardly fromthe outer end of each sleeve 52 defined by

end tiember 16a.

-14

r

Following this, a conventional manifold member 41 of

the type used in the previous embodiment, but preferably

equipped with screw threads, may be simply screwed onto threads

54, to provide a tightly sealed manifold member at each end

of the casing 10a, resulting in a finished dialyzer.

L By the above techniques, a simple means is pro- vided to eliminate complex sealing apparatus carried by the

C centrifuge for preventing the outward migration and leakage

of the sealant from the ends of the casing 10 or 10a, with

the complex centrifuge seals being replaced with a simple

and disposable cup-shaped member having improved sealing

reliability.

I The above has been offered for illustrative pur-

poses only and is not intended to limit the invention of this application, which is as defined in the claims below. to o S. *1 S

4

t

S

*e

15 15

o i

Claims (1)

1. The claims defining the invention are as follows:

   1. The method of potting the ends of a bundle of of pr

   hollow fibers positioned in a casing, which comprises: cisin

   inserting said bundle of hollow fibers into said casing posit

   through an open end thereof; sealingly closing the ends carou

   of sa-c casing by attaching casing closure member means to said

   said casing; attaching opposed, side-mounted outlet ports the ci

   of a hollow, elongated potting boat member to side aperatures carou

   positioned in fluid communication with said casing; placing

   curable liquid sealant into said hollow, elongated member; means

   and spinning said casing ends about an axis of rotation H to the

   extending through a central portion of said casing; whereby of th

   said liquid sealant migrates by the centrifugal force of said said

   spinning to the interior ends of said casing through said side

   apertures to pot the ends of the fiber bvaidle within the means

   casing; and, after said liquid sealant has cured, removing about

   said casing ends and cutting through said sealant and hollow casin

   fibers at each casing end to expose the bores of said hollow

   fibers. pract

   2. The method of claim 1 in which said side apertures ends

   are positioned adjacent opposite ends of said casing and posit

   generally pointing in the same direction. carou I C*

   3. The method of claim 2 including the further step said

   of surrounding the ends of said bundle with tape prior to certr

   insertion of said bun>q.e into said casing. platf

   S means I -16-

   4. The method of claim 2 comprising the further step

   of practicing said method by simultaneously spinning the

   casing ends of a plurality of separate casings in centrifuges

   positioned in a series of stations mounted on a rotating

   carousel platform, and initiating said spinning, terminating

   said spinning, and loading and unloading said casings from

   the centrifuges at at least one station positioned at said

   carousel platform.

   The method of claim 1 in which said closure member

   means is removably attached by interlocking helical threads r* 4

   to the casing, and is removed from the casing without cutting 4 V. V of the casing closure means prior to the step of cutting of 4. said sealant and hollow fibers at each casing end. S...C 6. The method of claim 1 in which said closure member

   means is cut through by cutting a circumferential channel

   about said closure member means adjacent each end of said

   casing, and then slicing through said sealant and hollow fibers. .4

   The method of claim 1 comprising the further step of 4t practicing said method by simultaneously spinning the casing *P 4 ends of a plurality of separate casings in centrifuges

   positioned in a series of stations mounted on a rotating

   carousel platform, and initiating said spinning, terminating

   4; said spinning, and loading and unloading said casings from the

   certrifuges at at least one station positioned at said-carousel

   platform. 4 8. The method of claim 1 in which said closure member

   means is totally removed after said liquid sealant is cured.

   -17- (/i

   K

   Y1 I I U__i

   1 1-1 I

   9. The method of claim 1 in which the entire amount

   of curable liquid sealant used is placed centrally into said

   potting boat member prior to spinning said casing ends.

   The method according to claim 1 wherein said

   closure member means comprises a cup-shaped member connected

   in sealing relation at its rim to the ends of said tubular

   casing, a portion of said cup-shaped member adjacent said

   rim being of relatively enlarged diameter, relative to said

   tubular casing, each said cup-shaped member also defining

   an extended cylindrical portion, positioned remotely from said rim, having a diameter less than said relatively a

   enlarged diameter portion and receiving an end of said hollow

   fiber bundle. 11. The method of claim 10 in which each cup-shaped

   member is integrally sealed at its rim to an end of said

   tubular casing.

   0 12. The method of claim 1 substantially as hereinbefore a.

   described with reference to the accompanying drawings.

   13. An elongated, tubular casing containing a bundle

   of hollow fibers when prepared by the method of any one of

   a the preceding claims. 4

   DATED this 25th day of February, 1983

   BAXTER TRAVENOL LABORATORIES INC.

   By their Patent Attorneys

   ARTHUR S. CAVE CO

   -18-

   C" r^ i^ n -Ai

   II 1 1A 11 II L il

   ii

   45236M7

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