CA1299552C

CA1299552C - Centrifuge rotor having a flexible carrier with restoring cap assembly

Info

Publication number: CA1299552C
Application number: CA000498144A
Authority: CA
Inventors: Paul Morrison Cole; William G. Johanson; Ronald Frank Mcconnell; William Edward Velvel; Peter Popper
Original assignee: EI Du Pont de Nemours and Co
Current assignee: EIDP Inc
Priority date: 1984-12-21
Filing date: 1985-12-19
Publication date: 1992-04-28
Anticipated expiration: 2009-04-28
Also published as: EP0186863A2; IE57312B1; IE853239L; GR853118B; EP0186863A3; DE3576467D1; EP0186863B1; DK598085A; DK598085D0

Abstract

A CENTRIFUGE ROTOR
HAVING A FLEXIBLE CARRIER
WITH RESTORING CAP ASSEMBLY

Abstract of the Disclosure A centrifuge rotor with a central hub is characterized by a flexible carrier formed from a plurality of fibers arranged in a predetermined textile structure. The carrier has a socket formed at the radially outer end thereof by the interconnection of the fibers. The socket may receive a vessel therein. A restoring cap assembly responds to centrifugal force to displace from its initial to final positions. As it returns the cap acts against the flexible carrier to assist the same to the first position.

Description

lZ~S~;2 A CENTRIFUGE ROTOR
H~VING A FLEXIBLE CARRIEP~ -WITH RESTORING CAP ASSEMBLY

Thi6 invention relates to a rotor for a cen~rifuge and in particular to a ~winging bucket centrifuge rotor whi~h includes a flexible carrier and which ha6 a re~toring cap as6embly opeLative to restore the ~ample carrier to a po6ition in which the axi6 of the 6ample container 6upported by the sample carrier lie6 substantially parallel to the axi6 of rotation of the rotor.

15DESCRIPTION OF THE PRIO~ ART
Swinging bucket centriEuge rotors are well ~nown in the art. Such devices are operative to expo~e a liquid fiample di6po~ed within a ~ample containe~ to a relatively high centrifugal force field. Such rotor~, when u6ed in device6 generally known as "ultracentri-fuge~, may be eitheL of the fixed angle or the 6winging bucket type.
~ ith a 6winging bucket-type centrifuge rotor the sample container6 are ~upported within carrier6 which are oriented 6uch that in an initial po6ition the axi6 of each carrier and the 6ample container therein extend6 parallel to the axi6 of rotation of the centrifuge rotor. However, during roto~ operation the carrier and the sample container therein pivot6 to an operational or working position wherein ~he axi~ of ~he ~ample container i6 perpend}cular to ~he ax~ of rotation of the rotor.
Due to the ext~emely high centrifugal force6 involved in ultracentrifuga~ion, ~generated by rotor speed~ that are often in exce~s of 50,000 revolution6 12~5S~

per minute), extreme care mu6t be taken ~o provide a 6ecure pivo~al at~achment for ~he carrier as it ~eciprocally piV0~6 between tha initial to the working po6itions. Typically ~uch pivoting arrangement6 use a hanger which include~ a hook-like appurtenance formed (ty~ically integrally) with the carrier. The hanger engage~ rod-like trunnion~ ~uitably mounted on the rotor body. ExemplaLy of ~uch pivoting arrangement~
are those 6hown in United States Patent 3,752,390 (Chulay) and United States Patent 4,190,195 ~Chul~y et al.). United States Patent 4,400,166 (Chulay et al.) relates to a modified carrier in which the Upp8L end thereof is provided with a tran~ver~ely extending opening through which a trunnion ba{ extend6. The bar i~ received at it6 extremities in vertically disposed guide ways provided in the body of the rotor.
One of the perceived di~advantage6 with the pre6ent generation of ultracentrifuge rotor~ of the ~winging bucket type i~ believed to involve the complexity of the hanger attachment on which ~he pivotal movement of the carrier occurs. Moreover, ince thi6 point of attachment i~ the weake~t link the ~winging bucket rotor must be ~ade nece~sarily bulky in order to provide the requisite 6upport for ~he carrier6. Thi6 bulk detract6 from the ro~or performance by increa6in~ acceleration and deceleration time6~ It al60 mandates increa6ed centrifuge rotor containment requirement~ and ~educes acce6sibility to the 6ample containe~.
Accordingly, in vie~ of the foregoing, i~ i~
believed advantag~ou6 ~o provide a swinging bucket centrifuge ro~o~ which uses the flexible deformation of the ~aterial of a flexible carrier to ~upport the ~ample containers and accommodate their movement from a fir~t, re~t, position to the 6econd, operational, ~29gS~

position which overcome6 the above-di6cu66ed perceived disadvantages of the prior art.
At the completion of a centrifuge run i~ i6 important that the carrier and ~ample container supported thereby be restored to it6 initial orien~ation so that g~adients formed by centrifugation will not be di6turbed. ~i~h ~his goal in mind i~ i~
believed advantageou6 to provide a rotor cap assembly o~erative to a~6i6t the return of the flexible ~ample carrier ~o the initial position.

SUMM~RY OF THE INVENTION
The pre~ent invention relate~ to a centrifuge of the ~winging bucket-type which, in its broade6t aspect. compri6e~: a centcal hub connectable to a source of motive energy; and a flexible sample carrier connectable to the hub. The carrier has a bendably deformable region in the vicinity of the periphery of the hub to permit a 6ample container carried and 6upported by the carrier to move under the application of centrifugal force from a fir6~, rest, position to a second, operational, po6ition. The motion of the sample container i6 accommodated by the flexible defor~ation of ~he material o~ the sam21e carrier rathec than by the pivotal motion of rigid member~
with respect to each other. The same material that deforms to accommodate motion of the container also accepts the ten6ile load impo6ed on the con~ainer and the carrier by centrifugal force.
In accoLdance with thi~ invention the sample carrier i~ fabricated from a plurality of fibers arranged in a textile structure. The fiberfi are 6uitably inte~connected to form at the radially outer end of ~he car~ier at lea~t one sling-like ~ocket.
The 60cket may be formed from the fibe~s connected to ~95~Z

themselves with or without the ufie of suitable "helperl' yarns and/oc rigidization so as to exhibit adequate strength to resi6t the hydro6~atic pre6sure developed within the liquid sample by centrifugation.
In thi~ event the 60cket may directly receive the 6ample container. Alternatively, the ~ocket may receive a vessel able to withstand the centrifugation pres6ure. The ve6sel i~ sized ~o accept the ~ample container. In the event that a ~es6el i~ provided a suitable force transmission arrangement, f or example, in ~he form of a footing or saddle, may be needed to transmit ten6ile load~ imposed on the ~ontainer and the vessel to the flexible carrier.
The fiber~ which form the carrier may be arranged in any textile structure, e.g., ~trand6, braids, o~
weaves. In addition, the fibers of the carrler may be arranged in the form twisted or plied structures or knits. The carrier may be rigidized, as by re~in impregnation, in the region of it6 attachment to the hub and/or at the radially outer end6. In the strand or braided embodiment6 the fibers are arranged 60 as to diverge from each other ~o define an opening throuqh which acce6s $o a sample container ~ay be afforded. In the weave embodiment the fibers are arranged in a woven stLap which i~ laid back on it~elf in which access to the sample container may be obtained from between the p}ies of the strapO
A rotor may be as6embled from a plurality of sa~ple carriers a~ de6cribed above which are layered acros6 the hub. Alternately a rotor may be formed without layering u~ing a flexible cacrier in which the plurality of 60ckets thereon are flexibly interconnected to define a central web region which is ~uitably attached to the hub.

1~9S52 In accordance with thi~ invention a cap as6embly i6 mounted to the ro~or for rotation therewith. The cap is responsive ~o centrifugal force a6 She rotor 6pins by moving from an initial ~o a final, rai6ed, po6ition to pe~mit the carrier to move from the first to the second positions. As the rotor ~lows the cap responds to gravity to move toward the initial po6ition. As ~he cap returnfi to the initial po~i~ion it in~eract6 with the carrisr to assis~ in restoring the carrier to the first po6ition.
The cap as~embly includes a central di~k with a skirt depending from the di6k. The skirt has an array of scallop6 therein. Each 6callop corresponds to a containe~ carried by the carrier. The height of each 8callop i6 arranged in accordance with the height above the hub that i6 occupied by the carrier corre6ponding to the scallop.
A lifting mechanism i~ as~ociated with the cap a~embly to as~i~e in raising the cap to its final position. In various embodiment~ the lifting mechanism u~e~ the ef~ect of centrifugal force on pivotally mounted cams, entrapped lug6 o~ projecting ~ibbon li~ter6 to raise the cap a~embly. In an alternate embodimen~ the cap incluaes 6pring aLm~
which are rai6ed in re~po~e to centrifugal force and which re6iliently act again6t the carrier to re6tore the 6ame to the fir~t po6ition. If the spring arms are utilized, the 6kirt is omitted.

BRTEF DESCRIPTION OF THE DRAWINGS
The in~ention ~ill be more fully under6tood from the following detailed de6cription thereo~ taken in connection with ~he accompanying drawing~ which ~orm a part of this application and in which:

g~Z99SS2 Figure 1 i~ a ~ide elevational view entirely in section of a centrifuge rotor having a layered 6tack of flexible carrier~ in accordance ~i~h one embodiment of ~he present inven~ion in which the textile 6tructure of each carrier i5 arranged in ~trands:
Figure 2 i~ a plan YieW ~aken along view lines 2-2 of Figure l;
Figu~es 3 and 4 are views 6imilar to Figures 1 and 2, re6pectively, illustrating a centrifuge ro~or ha~ing a layered 6tack of ~lexible cacrier6 in accordance with ~nother embodiment of the ~resent invention in which the textile structure o~ each carrier i6 arranged in a braid;
Figures 5 and 6 are view6 6imilac to Figures 3 and 4, re6pectively illu6trating a centeifuge rotor having a layered ~tack o~ flexible carriers in accordance with still anoth~r embodiment of ~he pre6ent invention in which the textile structure of each carrier i6 again arranged in a braid;
Figure 7 i6 an enlarged view of the arrangement of ~he braided 6tructure including helper yarn6 which cooperate to define the 60cket in the carrier ~hown in Figure6 S and 6;
Figure~ 8 and 9 are views 6i~ilar to Figures 3 ÆS and 4, re6pectively illu~trating a centrifuge rotor having a layered stack of flexible carriers in accordance with still another embodiment of the pre6ent invention in which the textile ~tructure of each carrier i~ arranged in a weave;
Pigure 10 i~ an enlarged view of the portion of the woven strap used ~o form the carrier 6hown in Figure6 8 and 9 in the vicinity of the rotor hub:
Pigure 11 i~ a highIy ~tylized per6pective view of an al~ernate embodiment of a flexible carrier in accordance wi~h the pres*nt invention:

~2~315~i~

Figure 12 i~ a side elevational view in 6ection of a re~toring cap as6embly generally u~ed with a flexible car~ier (shown in outline) in accordance with the present invention with the C3p on the left ~ide of the Figure in the initial position and on ~he right ~ide of ~he Figure in the rai6ed po~ition;
Figure 13 i~ a developed view of the skirt portion of the restoring cap a~6embly ~hown in Figure 12;
Figure~ 14 and 15 are, respectively, a front and a side elevational view of the re~toring cap a~sembly u6ed with a flexible carrier in accordance with the pre~ent invention with the cap in ~he initial position:
Figure 16 is a plan view taken of the re6toring 15 cap aB8embly taken along ~iew lines }6-16 of Figu~e 14 with portions broken away;
Figure 17 i6 a side 6ectional view of the re~toring cap as6embly shown in Figures 14 ancl lS with the sap in the rai6ed po6ition:
Figure 18 is a 6ide elevational view of an alternate embodiment of the re6toring cap ac6embly used wi~h a flexible carrier (~hown in outline) in accordance with the present invention while Figure 19 i6 a plan view thereof with ~ortion6 broken away:
Figure 20 is a side elevational view of yet another alternate embodimen~ of the restoring cap a~6embly used with a flexible carrier (shown in outline) in accordance with the present i~vention while Figu~e 21 i6 a plan view thereof: and Yigure 22 i~ a side elevational view of 6till ano~her embodimen~ of the r46toring cap assembly u6ed with a flexible carrier ~shown in outline) in accordance with the present invention and Figure 23 is a plan view thereof.

~LZ~ii52 DETAILED DESCRIPTIQN OF THE INNENTI~N
Th~oughout the following detailed de6cription, similaL reference nume~al6 refer to similar -elemen~s in all figures of the drawings.
A ~winging buc~et cent~ifuge rotor generally indicated by reference characte~ 10 in accordance with the the present invention includeE; a ~a~ple ~arrier generally indicated by ~eference character 38 which, in its b~oadest aspect. i6 f ormed of fîbers ar~anged in any predetermined tex~ile structure such that the carrier bendably deforms to accommodate ~otion from a first, rest, position ~o a second, ope~a~ional, po6ition. The rotor 10 described herein is primarily used in ult~acentrifuge in6truments wherein the rotational 6peed is in exce~s of 50,000 ~evolution6 ~er minute, although it shou}d be understood that its use i6 not limited exclu~ively thereto and thus may be used in any centLifuge insteument.
The centrifuge rotor 10 include6 a central hub generally indicated diagrammatically by refe~ence characte~ 12 that i6 connectable (as indicated by the schematic dri~e connection 16) to a suitable source of motive energy such a~ a drive ~OtOI ~4 for rotation of the hub 12 about a central vertical axi~ of rota~ion 2~ 12~. As is illustrated in Figure 1 the hub 12 includes a pede6tal 18 having a hollow 20 ~ormed therein. A ~uitable drive connector (not sho~n) is ~eceived within the hollow 20 to interconnect the rotor 10 wi~h the drive motor 14. The upper end of the pedestal lB includes a rece66 22 ~hich i~ ~ized to receive ~he shank 24 of a substantially disk-like base member 26. The upper surface 28 of the base member 26 i6 6ubstantially planar (althou~h, a~ developed herein, it ~ay be g~ooved) and p~ovided with a ~ounded periphery, a~ shown at 30. The pedestal 18 and the ~z99~

base member 26 are securely interconnected by a pres~
fit and 6ecured wi~h a threaded bolt 32. Rotative force i6 positively applied through the pede~tal 18 to the base 26 by mean~ of the pre6s fit and an array of drive pin~ 3~.
The embodiment of the flexible sample carrier 38 ~hown in Figure6 1 and 2 is bendably deformable in the vicinity ~0 o~ the periphery of the hub 12 to permit a ~ample container 42 carried and 6uppor~ed by the carrier 38 to move under the application of centrifugal force from the fir6t, rest, po6i~ion ~hown in the left ~ide of Figure 1) to a ~econd, operational, position (~hown in the right ~ide of Figure 1). In the first, rest, po6ition the axi~ 38A
o~ the portion of the car~ier 38 near to the 6ample container 42 i6 ~ubstantially parallel to the axi6 o~
rotation 12~. In the second, o~erational, po6ition the axi~ 38A of the carrier 38 near to the sa~le container 42 i~ 6ub6tantially perpendicular tO the axi~ 12A. The axi~ 38A of the carrier 3B i6 coilinear with the axis 42A of the ~ample container 42A. ~he ~ovement of the carLier 38 and the 6ample container 42 carried thereby i~ acco~modated by the flexible deformation of the material of the carrier 38 rather than by the pivotal movement of rigid member~ with re6pect ~o each other. The ~ame ~aterial ~hat deforms to accommodate mo~ion of the carrier al60 accept~ the tensile load impo6ed on the ~ample container 42 and the carrier 38 by centrifugal force.
A6 6een in ~igure6 1 and 2 each ~ample carrier 38 there 6hown i~ an elongated element in which the f iber~ are arranged in the textile structure o~
6~rand6 46. By "6trand~ it i~ meant any twi6ted, braided, interlaced, plaited or e66entially parallel array o~ fiber6 formed i~to a cord. Pref~Iably, but not neces~arily, the ~trand6 46 pass 6ubstantially radially acros~ the hub 12 and are attached at their midpoint6 to the hub 12. Alternatively, th~ 6trands may take a partial wrap of any predetermîned angular di~tance (including sub6tantially 180) about the hub 12. At least one radially outward end of the element 3~ the 6t~and6 46 are interconnected ~o define a ~ling-like ~ocket ~8. The ~trand~ 46 are formed from a high 6~rength fiber material such as the aramid fiber manufactured and sold by E. I. du Pont de Nemour6 and Co. under the trademark KEV~AR~. Of course, other suitable material6 may be used.
As will be developed the socket 48 may be formed by connecting the strands 46 to ~hemselves either with or without the use of suitable "helper" yarn6. In addition, as iB also set forth herein, each 60cket 4B
may be rlgldized, preferably by resin impregnation, to develop in the 60cket 48 s~fficient 6trength to resi6t the pre~6ure exerted within the ~aMple by centrifugation. If the socket 48 can be formed to exhibit the requisite strength the socket ~ay directly receive the sample container 42. Alternatively ~he ~ocket 48 accepts a ve66el 50. The vessel 50 i6 a thin walled element which provide6 a~ imperviou6 member about a liquid ~ample. The axis 50A of the vessel is collinear to the axis 38A. The u~e of a ve~#el 50 may mandate the use of a suitable force tran6mitting element 52 which prefeLably take~ the f orm of a saddle (Figure6 3 and 4) or a f ooting (Figure~ 8 and 9~. The tran6mitting element 52 6erve6 to tran6mit loads that are impo6ed on the 6ample container 42 to the flexible carrie~ 38 80 a~ to impart a 6ub6tan~ially unifo~m stre~6 to the fiber~ o~
the carrier.

~0 ~2~9~i5;~

The ~trands are relatively lightly inte~connected to provide a mo~e con~olidated 6tructure intermediate hub 12 and the radial end6 of the carrier but not to the extent where the flexibility of the car~ier i~
impaired. As the ~t~and6 46 pas6 radially inwardly toward the hub 12 they cooperate to define gap6 58 (Figure 2) through which acce~s i~ afforded to the ~ample container 42.
As alluded to ea~lier the car~ier 3B may be rigidized, a6 by resin impregnation, in a central region 60 that lie~ in the viciniey of the hub 12 and in ~he radial o~ter region6 62. However, tha~ portion of the carrier 38 inte~mediate the rigidi~ed region~
60 and 62 define~ the flexibly deformable region 40.
This region 40 may be impregnated with a nonrigidizing matLix that improves to ~urface characteri6tic6 without impairing its flexibi}ity.
To manufacture the ca~rier element 38 shown in Figures 1 and 2, a 6ingle ~trand of fiber may be looped about a central mandrel to form one. ~wo or more 60cke~. The mandrel may become a pe~manent part of ~he fabricated rotor or may be removed. A collar having a number of articulating arm~ i6 81ip ~it to the ~andrel. The arms can be extended and made ~igid during a winding pha6e and relaxed when the winding is complete. Each end of each arm may carry an end member which ~eplicate6 the ~ize and feature~ of a ve6~el carried in the 60cket. The 6trand is wound abou~ the mandrel and the number of ~nd~ to form the desired number of 60cket6. The strand ~hould uniformly 6urround each end and, therefore, the winding angle of each ~ass mu6t be slightly varied. A
matrix material or the addition of helper yarnE may be necea6ary to maintain the position o~ ~he ~t~and. The 6ample carrier may be imp~egnated to define the rigidized region6 60, 62 discu6sed above.

In Pigure6 1 and 2 the rotor 10 is 6hown a~
fabricated from a plurality, e.g.. three, sample carriers 3B-1, 38-2 and 38-3 which are layered over the hub 12. Of cour~e, any convenient number of carriers 38 may be received on the hub 12. The particular number and arrangement of carriers 38 selected will determine the sample capacity (in terms of container place6) of the rotor 10. The axis of each carrier 38 is arranged at a predetermined angle A
~Figure 2) with re6pect to the axi6 of the adjacent carrier. A clamp plate 66 i8 ~ecured to the hub 12, a~ by bolt~ S8, ~o 6ecure the layered car~ier~ 38 to the hub L20 The bolt6 68 appear in 6ide eleva~ion only in Figure 1.
To accommodate the plural layered carrier6 38 the lower ~urface of the clamp plate 66 and/or the upper 6urface of the ba6e 26 of the hub 12 are provided with radially extending groove~ 66-1, 66-2 and 66-3. In the Figure6 only the clamp plate 66 i6 grooved. The axi6 of each groove i6 coincident with the axi~ of one o:f ~he layered carLier~. The depth of any one of the grooves 66 i6 6U. ficient to accommodate the carrier received in that groove plu6 the carrier~
layered above it which }ie in other groove6.
Generall~ the de~th of each groove i~ an integer ~ultiple of the height dimension of a ~tacked carrier taken at the hub. Centering the car~ier6 38 within the grooves may be provided by adhering at lea~t one 6ide of each carrier to a thin metal plate 70 in the form of a modified cross that enter6 into at least two adjacent grsove~. The carrier6 38 may alternatively be drilled at their center or have a hole formed therein which allow6;the fiber6 in the carrier to pas~
therearound in a ~treamline fa6hion and a central 6houlder bolt 72 provided through the clam~ plate 66 ~9~52 and into the base 26. (The bolt 72 i6 6hown in phan~om only in the plan views of Pi~ure6 2, 4, 6 and 9~. The carrier 38 may be held in the correct posi~ion on the base 26 by mechanical expedient6 (e.g., clamps, pin6 or bolt6), by cemen~ or adhesive or by EpeCial geometrie~ (e.g., po6itioning plate6 or groove6 ~ .
In operation, as the rotor 10 i6 spun ~he ~ample containers 42 carried in the ve~6el6 5Q or directly received in the 60cket~ 48 move from the fir6t, re6t, position 6hown on the left side of Figure 1 (in ~hich the axis 38~ of each sf the carrier6 38 lies 6ub6tantially parallel ~o the ~pin axi6 12A~ to a second, operational, po~ition (in which the axis 38A
of each of the carrier~ 3B i~ substantially perpendicular to the 6pin axi6). The motion i~
accommodated by the ~lexing of the nonimpregnated flexibly de~o~mable region 40 of each carrier 38.
Under deceleration the cever6e motion occur6.
In accordance with another embodiment of the pre6ent invention carrier 38 i6 arranged in a braided textile ~tructure. In one a6pect the braided textile structure i~ defined ~rom a braided cord 76 attached to both the hub 12 and at least one foree tran6mitting element 52~ In the prefe~red ca6e the cord i6 provided wieh clo6ed eyelets 78A and 78B at each end thereof. The eyelet6 78 are preferably fo~med using an eye-splice in which the end of the cord 76 is 6~1iced back into the cord body to form an eyelet although any 6uitable technique may be used.
In the preferred in6tance the force tran6mitting element 52 ~ake6 the form of a hor6e6hoe-6haped ~addle 82. The ~addle 8~ i6 provided with a central bore 84 which receive6 the ves~el 50. A sample container ~ay be received in the ves6el 50. The exterior surface ~99~

of each 6addle 76 i~ provided ~ith an array of groove~
8B-l, B~-~. 88-3, and 88-4 to facilitate the wrapping of the saddles with the cord 7fi. A~ seen in ~igures 3 and 4 two saddle~ 82 are erovided on each c~rrier 38 and are denoted by the characters 82A and 82B
e6pectively, although it i~ to be noted that a carrier 38 in accordance with thi~ a6pect of ~he invention may be formed u6ing a single 6addle 82. In this in6tance both eyelet6 78~, 78B ~urround ~he same 6addle.
One winding pattern that has been found useful in forming a braided 6tructure f~om a cord 76 having eyelets 78A and 78B at each end thereof may be described. The eyelet 7BA i6 provided in the groove 88A-1 o the 6addle 88A. The cord 76 is then wrapped ~equentially around the groove6 88B~ 8A-l and 88B-l. Thereafter the cord 76 i6 wrapped about the ~rooves 08A-2. B8B-2, 88A-2 and ~8~-2. In order to form a mirror image the cord 76 i8 temporarily po6itioned (but not permitted to 6eat) in ~he groove 88A-3 and then provi6ionally positioned into the groove 88B-3. The cord 76 thereafter wrap~ around the groove 88~-3 underneath the previously depo6ited wrap, thence to the groove 88B-3 undernea~h the previou~ly depo~ited wrap. ~he provisionally held wraps are then 6eated. The cord 76 then provi~ionally loop~ the grooves 88A-4 and 88B-4~ The cord 76 wraps the groove 88A-4 underneath the previou61y depo~ited wrap and finally to the groove 88B-4 where the eyelet 7BB is ~i~po~ed underneath the previou61y deposited wrap.
The provi~ionally held wraps are then seated. To equalize leng~h~ the ~addle~ 82A and 8ZB are 06cilla~ed at load6 up to approximately twenty-five perce~t of the breaking strength of the sy~tem so formed or a minimum of ten repetition~. The 1~9~S52 apertureg 90 (Flgure 4) in each ~addle 62 facilitate the insertion onto the 06cillating device. The ~tructure may be rigidized by impLegnation -t-o define the region6 60, 62 therein. Acces~i opening6 58 are defined. A rotor 10 may be ~ormed of plural layer6 o~
carrier6 38 as di6cussed above.
In the embodiment of Figuce~ 5 and 5 the braided 6tructuce u6ed to form the carrier 3~ i6 defined from a plurality of cord6 92 (each of which i6 it~elf a braid in the ~o~t preferred case). The cords 92 are radially and coaxially di6po6ed in the vicinity of the hub 12 while the free ends thereof are braided to form the 60cket 48. The p~eferred mode o~ ~ormin~ ~he 60cket 48 i6 6hown in Figure 7 in which the cords 92 are interlaced by hel~er yarns 94 which pas6 over and under the cords 92. The free end~ of the helper yarns 94 and the free ends of the cord6 92 are consolidated, a~ at 96, by any 6uitable expedient, such as braiding. A}ternately. the fibers which form the braided cord~ 92 may be u~ed to braid the ~ocket 48, with the end~ suitably con601idated. In an alternative ~ode, the free end~ of the cords 92 and the helper yarns 94 ~or the ends of the fiber~ which form the cord6 92) ~ay be braided back onto themselve~, thus eli~inating the need for con601idated region 96. If the ~ocket 48 exhibit~ sufficient ~trength to contain pres6ure exerted by the li~uid ~ample during centrifugation the container 42 may be directly received within the ~ocket 48 (Figures 5 and 6).
Alternatively the ve~sel 50 is erovided within the 60cket 48.
The cacrier 38 i~ rigidized in both the central and radial outward region~ 60 and 62, respectively.
Rigidizin~ the ou~e~ region 62 a66i~t6 in maintaining the braid of the socket 48 regardle~ o~ the manner in which the 60cke~ i6 formed.

l~9~S52 The cord6 92 need not extend radially acros6 the hub 12, but may be bent 180 ~o that each end of each cord 92 is adjacent. The~e end6 may ~hen be- used to ~orm a carrier 38 wi~h a 6ingle socke~ 48. In thi~
ca6e a ~ubstantial load re~isting attachment must be provided to the hub. Suitable acces6 openings 58 may be provided wheLeby acce~6 to the container 42 may be had while the carrier 38 i6 in the first position.
Carriers 38 may be layered across the hub akin to the situation discu6sed in connection with Figures l and 2. The clamping action of the plate 66 in cooperative as60ciation with the base 26 secures the carriers 38 to the hub 12 a6 discu66ed above~ In both braided embodiments the cord 76 or the cord6 92 ~ay be made ~rom the same material as used for the strand6.
A6 ~een from Figures B and 9 the samp~e carcier 3B arranged in a woven textile structure is defined from a woven belt or ~trap 102. The strap 102 i~
woven from high strength fiber material ~uch as that used for the strand~ or the braids. Preferably a majority of the fiber6 of the belt 102 are arranged longitudinally, that i~, a~ the warp o~ the weave and para}lel to the axiç 38A. Thi~ pattern i6 preferred to enhance the ~rength of the belt 102 in the direction of it6 expo~ure to maximum load.
The belt 102 i~ overlaid back onto it6elf to form, in bowtie-like fa~hion, one or more lobe~ 104.
A paie of lobes 104A, 104B, one at each radial end of the carrier 38, i6 preferred. Preferably the belt 102 i~ overlaid in u~h a manner that a plurality of plies Qf woven material i~ defined. As seen from Figure lO
~he direction of looping i6 indicated with the numbered arrows illu~trating the plies in each direc~ion. Starting ~ith an end lO~ the belt 102 is ; 35 wrapped back on it~elf ~uch that at lea~t ~hree plies ~29~552 extend in each of two opposed radial directions acro~s the hub 12. The plies are thus overlapped six deep acro~s the face of the hub 12. In the vicinity of the periphe.ry 30 of the hub 12 the plies heading in opposed directions diverye to define the lobes 104.
The free end 110 of the belt 102 is di~posed eithar above or below the overlaid plies depending upon the di~ection of looping. At lea~t 8iX plie6 are preferred to enhance ~he radial 6~rength w~ile 6imultaneously providing flexibility o~ ~he carrier.
The stacked plies define a height dimension ~16.
~lternately the wovçn carrier 38 may be formed from a number o~ ne6ted endles6 strap6.
On the interior surface of the radially outer end6 of each lobe 104 is disposed a force transmitting member 52 in the form o footing 120. The exterior 6urface 122 of the footing 120 iB configured for clo6e fitting receipt on the curvlng interior turn o~ the respective lobe 104 in which the footing 120 i8 dispo6ed. The footing 120 has a pocket 12~ on the inner sucface the~eof. The vessel 50 having an enlarged cylindrical ba~e 126 i6 removably receivable in ~he pocket 124 in the footing 120. The ~ample container 42 carrying the 6amp}e under te~t may be received within the ve6sel 50. The ve6sel 50 is closed by a conical 6~0ppe~ 12~. The ve~el 50 is movable with re6pect to the footing 120 along the interface defined between the base 126. The ves6el 50 i~ removable ~idewise of the ca~rie~ 38 via the acce o~ening 5B defined between plies of the belt 102.
A plurality of carrier~ 38 may be layered, as in previous instance~, acro~6 the hub 12.
In some instance~ it may be desirable to form a rotor with a 6ample capacity (in terms of container place6) that i6 grea~er ~han two ~ithout the necessity ~L~99S~2 of layering a plurality of carLier6 38. Thi~ may be accomplished by a carrier 38' ~hown in Figure 11. In this e~bodimen~ the fibeI6 defining the individual ~ocket6 48~-1 through 48'-B are interconnected into a central web region 130 so that the carrier 38' is one inte~ral textile stIucture. one continuou6 yarn may be u6ed to form ~he carrier 38' or a number of yarn6 added and 6ub~racted during fabrication to in~ure a balanced, uniform stres6 pattern thLoughout the structure. The carrier 38' i~ suitably connected above or below the surface of the web 130 to the hub 12. The web 130 may be rigidized to define the ~egion 60, as di6cu6sed. The flexible region 40 ~s defined in the region between the periphery of the hub 12 and the radiating 60ckets 48. The 60ckets 48 may be rigidized in the web and at the ends, as discu66ed. A
vessel 5Q may be disposed within each ~ocket 4~
de ired or nece6sary. Each fiocket 48' iB provided with an acce66 610t 132 by which access to the interior ~o of the socket 48' may be afforded. In opeeation the movement of each socket 48' from the fir6t, re6t, po6ition in which its axis 48'~ i6 sub~tantially parallel to the axi6 of rotation 12A to ~he 6econd, operaSio~al, position in which the axis 4~'A i6 6ubstantially ~erpendicular to the axis 12A i6 accommodated by the flexible deformation of the carrier 38' in the regions 40'. The carrier 38' i~ formed in a braided textile structure i~ the preferred case.
--o--O--o--The stiffnes6 and thickness o~ the flexibly deformable region 40 i6 6uch that the weight of the carriers 3~, 38' and/or ve6sel6 and/or sa~ple containers load ~ay not permit gravity ~o fully re6~0re the ca~Liers ~com the operational to the rest ~o~ition. Accordingly it may be necessary to p~ovide 1~

~2~95S~

a mechani~m to a~6i~t in re6toring the carriers 38, 38~ to the fir~t, re6t, po6ition. Such a mechanism i~
pro~ided by a re~oring cap a6~embly 140 in accordance wi~h any embodiment of the pre~ent invention. It should be under~tood that any embsdiment of the re6toring cap a6sembly 140 ~hown in Figures 12 thro1lgh 21 may be used with any embodiment of the flexible carrier 38, 38' previou61y de~cribed 60 long a~
suitable provi~ion i~ made in the cap a~embly 140 to remove ~he sample from ~he cacrier 38, 38l in which it i8 6pun. In the Figure~ 12 through 23 the flexible carrier is shown only in oulline form.
The cap as6embly 140 in the embodiment 6hown in Figures 12 to 21 includes a substantially in~erted cu~
6haped member formed from an annular disk 142 with a central collar 144 ha~ing an aperture 145 therein. A
skirt 146 depends from the pe~iphery of the dis~ 142.
The lo~er end of the skirt 146 i8 provided with diametrical eair6 of scallop~ 148A, 148B and 14BC. as may be best 6een from the developed view of the skirt 146 shown in Figure 13. U6ing a baseline 150 defined by a line that ~a6ses through the lowest point on each 6callop 148 a~ a reference, it i6 seen that the 6callop6 148 extend variou6 predetermined height~ 152, 154, 156 above the ba6eline 150. Moreover the high points of adjacent 6callop6 148 are ~ertically offset, a~ 6hown ~t 158, 1~0 and 162.
In accordance ~ith this invention the number of pair6 of scallop~ 148 and ~he number of different predetermined height6 152, 154 and 156 that ~he scallop6 extend above the ba6elins 150 corre6ponds to the number of flexible sample carrier~ 3B u6ed on the rotor 10. In the in6tance illu6trated i~ Pigure6 12 and 13, if three carrier6 3B are used, three different di6tances D~152), D2(154) and D3(156) are defined.

~L2~SS~

The 6callop~ 148 having the greate6t height dimen~ion D3(156) are aligned ~ith the carrier 33-3 that i~ ~he uppermo~t of the layered carriers while the lea~t height dimen6ion Dl(152~ i6 radially aligned with the lowermost carrier 38-1. The 6kict 146 would be adju~ted to provide an appropriate number of ~callops 148 at the game predetermined height above the ba~eline 150 to accommodate the ~oc~ets 48' of a carrier 38'.
~ounted to the upper 6urface of the clamping plate 66 a6 by an axially extending bolt 168 i~ an up~anding po~t 170. The clamp plate 66, by vi~tue of it6 attach~ent to ~he di6k portion 26 by means of the counter6unk bolt6 68, may be es6entially viewed as a part of the hub 12. It i6 noted that the bolts 68 are 6hown only in Figure 12 for clarity of illu6tration.
It i8 to be under6tood that the clamp plate 66 shown in Figure6 14. 15. 16, 18, 20 and 22 i6 attached to the hub 12 for rota~ion therewith.. The upper end of the po6t 170 in ~he embodiment of Figure ~2 i6 provided with an enlarged head 172. The po6t 170 i6 dri~en with the clamp plate 66 by an ar~ay of drive pinB 173. The cap 140 i6 ~lidably received on the post 170 for movement in the direction of the arrow~
174, 176 ~arallel to the axi6 of rotation 12A.
Relative ro~ation theLebetween i6 prevented by a key 178 that extends radially from the post 170 and engage into notches 180 provided in the collar 144.
The operation of the cap as6embly 140 may be unde~tood ~rom Figure 12 in which the left hand side of the ~igure depic~6 the 6ituation extant with the sample carrier~ 38, 3~' in the first, re~t, position while the right 6ide of the Figure depict6 the 6ituation with the6e ele~ents in the second, opera~isnal, po6i~ion. At rest the radial end6 of the carrier6 3~, 38' hang o~er the rounded edge 30 o~ the hub 12 and the cap 140 occupie6 its initial po6ition in which the undersu~face of the disk 142 lays atop the upp0~ 6urface of the ~lamp plate 66. ~ the rotor 10 is spun the 6ample container~ are impelled to the 6econd po~ition. This movement is accommodated by the flexible deformation of the carLier 38, 38' as di6cu~sad above. A6 it moves ~he carrier 38 abuts the scallops 148 lifting the cap 140 in the direction 174 (parallel to the axi~ of rotation 12A). The cap 140 thu6 respond~ to centrifugal force to di~place in the direction 174 to the final, rai~ed, po6ition. The cap 140 remain6 elevated at it6 rai6ed po6ition while the rotor 10 iB at operating 6peed. The upward movement of the cap 140 i6 li~ited by abutment between the annular shoulder 144S on the ~ollar and the ~urface 172S on the under6ide of the enlarged head 172.
A8 the rotor L0 610w6 the cap 140 begin6 to move in the direction 176. The weight of the cap 140 is impre~6ed upon the ca~riers 38, 3B' a~ the cap 140 re6pond~ to gravity thereby a6sigting the return of ~he carrier~ 38, 38~ and the container6 carried thereby to the fir6t po~ition.
In 60me in6t~nce6 it may be de~irable to provide a lifting mechani m to a66i~t in li~ting the cap 140 to the ~aised po6ition. The embodimen~ o~ the invention shown in Figure~ 14 through 21 include 6uch a lifting mechani6m.
In the embodiment of the invention ~ho~n in Figures 14 through 17 the po6t 170' ha6 a hollow interior region as indicated at 172 and ha6 diametrically oppo6ed slots 180A, 180B (Figure 17) which extend ~ubstantially along the length hereof.
The collar 144 i6 61idably recei~ed on the ~ost 17Q' for relative motion in the direction6 174, 176 ~9SiS2 parallel to ~he axi~ of ro~ation 12A. The lower end of the po~t 170~ is provided with an snlarged base 182 whereby the po~t 170~ ~ay be secured to the clamp plate 66 by an array of bolt~ 16~. The under6ide of the di6k 14Z i6 rece~6ed, a6 at 184 ~Figure 17), to accommodate the head6 of the bolt6 168'. The collar 144 i6 provided with regi~tered openings 186A, 186B
which regi6ter with the slot6 lBOA, 180B, re~pectively.
The upper end of the po6t 173' i6 threaded to lo receive a guide holde~ l90 which i~ 6ecured nonro~ationally to ~he po~t 170' by 6et screw6 19Z
~Pigure 15). A pair of ~tepped 6eat6 194 are formed within the upper po~ti~n of the guide holder l90.
Each ~eat 194 receives a guide member 196. The guide~
196 are each provided with a groove 198 which, when registered, define an ax~ally extending channel 200 which communicate6 with the hollow interior 172 of the post 170'. The groove~ 198 continue over the u~per surface of the guides 196 and radially regi6ter with notche6 202 pro~ided in diametrically oppo6ed relation in the guide holder 190. The rim6 of the notche6 202 are rounded, a6 at 204. A cover ~late 206 is 6ui~ably ~ecured to the upper surface of ~he guide holder 190 by bolt6 208.
A pair of elongated ribbons 216A and 216B e~tend through the hollow interior 172 of the po6t 170', through ~he channel 200 defined between the con~ronting guide6 196, and cadially ou~wardly of the holder 190 th~ough the groove~ 19B and notche6 202.
~he lowe~ end of each ribbo~ is enlarged, a6 at 218 (Figure ~5), and i provided with an eye opening 220.
The cap a~6embly 1~0 i~ pinned to the ~ibbon~ 216 ~y a radially extendi~g pin 224 which extends through one o~ the opening6 186A in the collar 144, in~o the po~t : 35 170' through the 610t 180~ cor~e6ponding to the one . 23 o~ening 136A, through the regi6tered eyes 220 at the lower end~ of the ribbon~ 216, an~ then ~hrough ~he other of the ~lot~ 180B and the opening 1~6A. Spacer6 230 stand the pin 224 off the inner 6urace of the 5 po6t 170~. The ribbon~ 216 are formed of a 6uitably den~e material, as chrome steel, and configured to exert a predetermined lif~ing force on the cap assembly 140 deriYed in a manner to be discug~ed.
In operation, in the initial po6ition, be~t ~hown in Figure~ 14 and 15, the under~urface of the di6k 142 abut~ the ba6e 1a2 of the po~ 170'. A
predetermined length 234 (Pigure 1~) o~ the upper end of the ribbon6 216 extend6 radially outwardly of the guide holder 190. A6 the cotor rotate6 centrifugal force act6 on the radially projecting portion6 234 of the ribbon~ 216 drawing the ribbons radia}ly outwardly in the direction of the arrows 236. Concomitantly, the radial outward motion of the ribbons 216 lifts the cap as~e~bly 140 in the upward direction 174 via the interconnection of the lower end~ of the ribbons 216 to the collar 144 of the cap 1~0 through the pin 22~.
Thu6 a6 the rotor ~pins and the flexible carrier~ 38, 38' move a& earlier di~cussed the ribbon6 216 coopera~e to lift ~he cap 140 from the initial po6ition to the final, rai~ed, eosi~ion ~6hown in Figure 17). The action of the carrier 38, 38' again6t the 6kirt 146 as6i~t6 in lifting the cap 140. Upward ~otion of the cap a~6embly 140 i~ arre6ted by the abutment between the upper 6urface 144S of the collar 144 ~ith the annular under6houlder l9CS of the guide holder 190.
A6 the rotor ~low~ the cap a~sembly 140 is lowered in counter direction 176 a6 the weight of the cap 140 overbalance6 the lifting force generated by the action of centrifugal force on the ribbon6 216.

~2995~

The re~toring action of the 6kirt 146 on the carrier6 40 uLges the return of the ca~rier~ 38, 38' from the ~econd to the fi~t po&ition.
In the embodiment of the cap 140 ~hown in Figure~ 18 and 19 the po~t 170 i6 modified to ~rovide longitudinally extending 610t~ 23~ along a portion thereof. Pivotally mounted in the 610t6 238 are pivot element6 240. The elements 240 aLe mounted on pins 242 received in bore6 Z44 formed in ~he portion of the po6t 170 defining the ~Iot6 238. The inner ~urface of the core 142 i6 provided with cam follower surface 246.
In operation, while in the initial position 6hown in the left 6ide of Figure 18 the pivot element~
240 hang in a retracted po6ition within the 610t6 lS 238. A~ the rotor 10 6pins centrifugal force urge6 the pivot element6 240 radially outwardly into contact with the cam surfaces 242. This action lift~ the cap 140 along the post 170 in the upward direction of the a~row 174. A6 the rotor 610ws the weight of the cap 140 become6 do~inant, urging the car~ier6 38, 38' to the fir6t po~ition. ~ny predetermined number of pivot element6 240 and corre6ponding ~urface6 242 may be used .
With reference to Figure6 20 and 21 shown i8 6till another alternate embodiment of the cap a6sembly 140 embodying the teaching6 of the present invention.
In thi~ embodiment the disk L42 i6 provided with a tapering central member 248 having an array of radially outwardly extending arms 252. The di6k 14~
i~ ~lidable in the direction 17~, 176 along a guide : bolt 253 threaded to the clamp plate 66.
In this embodiment, at~ached to the upper 6urface of the clamping plate 66 by an array of bolt 168" i~ a central coLe 254. The cent~al core 254 include~ an array of gene~ally upwardly and outwardly ~2~95S2 inclined trackway~ 256. An array of radially extending ~lot6 260 i6 provided in the member 254 with each slot 260 interrupeing each ~rackway 256.- Trapped within each trackway 256 i8 a liftin~ lug 262. In the a66embled 6tate the arm~ 252 of the central portion 248 are rece;ved within the ~10~6 260 ~uch that the arms 252 pa~s through each trackway 256.
In operation, with the rotor 10 at the re6t as 6een in the left ~ide of Figure 20 the lugs 262 repo6e lower ends of the trackway6 256 with the lower edges Qf the arms 252 re6~ing above the lug6 262. A~ the ro~or 10 i6 ~pun the lug~ 262 are urged by centrifugal force to move within the trackways 256 in the direction of the arrows 266. The lug6 262 abut against the arm6 252 which pas6 through the track~ay 256. As the lug6 262 move in the trackway 256 they act again6t the acm6 252 li~ting the 6ame in the direction 174 alonq the guide bolt 253. The upward motion of the di6k 142 i6 limited by abutment with the ~houlder 142S on the di6k with the enlarged ~ead 253H
of the bolt 253, a6 6een in the right ~ide of Figure 20. A6 the rotor slow6, the lug~ 262 fall back into the lowest extremity o the trackway 256, with the arm6 252 following suit in the direction 176 to lower the skirt 146.
Shown in Figure6 22 and 23 are 6ide 6ectional and plan views 6howing an alternate embodiment of a cap a~6embly 140' of the pre6ent invention. In thi6 embodiment the cap a~6embly 140' includes a di6k 272 to which is appended an array of 6pring arm6 274. The di~k 272 and the arm6 274 are ~ecured to the plate 66 by the bolt6 276. The number of 6pring arm6 27~
correspond~ ~o the number of ~ample container6 40 ~upported in the socket6 48, 48' of the carrier6 38, 3~ on the rotor 10. The arm6 Z74 are fabricated from ~2~552 any 6uitable material, 6uch a~ chroma-vanadium 6pringsteel.
In operation, as the rotor 10 i6 . 6pun the centrifugal force effect~ on the flee end6 of the s 6pring arms 274 cau6es them to lift upwardly and outwardly in the direction of arrow~ 278 until the carrier6 38, 38~ and the arm~ 274 occupy the po~ition shown in the right 6ide of Figure 22. In this po6ition the end6 of the arm6 274 lie above the ends lo of carriers 38, 38'. A6 the rotor 610w6 the resiliency of ~he ~pring arms 274 again becomes dominant, urging ~he carriers 38, 38' in the direction 280 to the first po~ition.
Those skilled in the art may appreciate that in view of the preferred embodiment of the invention as above described numerou~ modification6 thereto may be effected. However the6e modi~ication6 are to be construed a6 lying within the scope of the pre6ent invention, ~fi s2t forth in the appended claims.

Claims

1. A swinging bucket centrifuge rotor for exposing a sample disposed within a sample container to a centrifugal force field comprising:
a central hub connectable to a source of motive energy for rotating the hub about an axis of rotation; and a sample carrier connectable to the hub, the sample carrier itself comprising a plurality of fibres arranged in a predetermined textile structure, the sample carrier having a flexibly deformable region such that the carrier is adapted to support the sample container during movement of the same in response to centrifugal force from a first, rest, position in which the axis of a portion of carrier in the vicinity of the container is substantially parallel to the axis of rotation to a second, operational, position in which the axis of the carrier is substantially perpendicular to the axis of rotation.

2. The centrifuge rotor of claim 1 wherein the hub has a periphery thereon and wherein the fibers are interconnected at a point radially outwardly of the periphery of the hub to define at least one sling-like socket adapted to receive the sample container therein, the carrier having a deformable region between the hub and socket which flexes to accommodate the movement of the carrier as it moves from the first to the second position.

3. The centrifuge rotor of claim 1 wherein the hub has a periphery thereon and wherein the fibers are interconnected at a point radially outwardly of the periphery of the hub to define at least oen sling-like socket, the socket being adapted to receive a vessel itself sized to receive the sample container therein, the carrier having a deformable region between the hub and socket which flexes to a accommodate the movement of the carrier as it moves from the first to the second position.

4. The centrifuge rotor of claim 1 wherein the hub has a periphery thereon and wherein the fibers are interconnected at a point radially outwardly of the periphery of the hub to define at least one sling-like socket, the socket being adapted to receive a vessel itself sized to receive the sample container therein; and a force transmitting arrangement adapted to transmit tensile loads imposed on the sample container and the vessel to the fiber textile structure; the carrier having a deformable region between the hub and socket which flexes to accommodate the movement of the carrier as it moves from the frist to the second position.

5. The centrifuge rotor of claim 2 wherein the socket further includes a helper yarn interconnected with the fibers defining the socket.

6. The centrifuge rotor of claim 3 wherein the socket further includes a helper yarn interconnected with the fibers defining the socket.

7. The centrifuge rotor of claim 4 wherein the socket further includes a helper yarn interconnected with the fibers defining the socket.

8. The centrifuge rotor of claim 2 wherein the socket is rigidized.

9. The centrifuge rotor of claim 3 wherein the socket is rigidized.

10. The centrifuge rotor of claim 4 wherein the socket is rigidized.

11. The centrifuge rotor of claim 5 wherein the socket is rigidized.

12. The centrifuge rotor of claim 6 wherein the socket is rigidized.

13. The centrifuge rotor of claim 7 wherein the socket is rigidized.

14. The centrifuge rotor of claim 2 wherein the textile structure takes the form of a pulrality of strands.

15. The centrifuge rotor of claim 3 wherein the textile structure takes the form of a plurality of strands.

16. The centrifuge rotor of claim 4 wherein the textile structure takes the form of a plurality of strands.

17. The centrifuge of claim 14 wherein the textile structure has gaps formed therein through which access to the sample container is afforded.

18. The centrifuge rotor of claim 15 wherein the textile structure has gaps formed therein through which access to the sample container is afforded.

19. The centrifuge rotor of claim 16 wherein the textile structure has gaps formed therein through which access to the sample container is afforded.

20. The centrifuge rotor of claim 2 wherein the textile structure takes the form of a weave.

21. The centrifuge rotor of claim 3 wherein the textile structure takes the form of a weave.

22. The centrifuge rotor of claim 4 wherein the textile structure takes the form of a weave.

23. The centrifuge rotor of claim 20 wherein the weave defines a belt of a high tensile strength material having at least one lobe spaced raidally outwardly of the hub.

24. The centrifuge rotor of claim 21 wherein the weave defines a belt of a high tensile strength material having at least one lobe spaced radially outwardly of the hub.

25. The centrifuge rotor of claim 22 wherein the weave defines a belt of a high tensile strength material having at least one lobe spaced radially outwardly of the hub and wherein the force transmitting arrangement comprises a footing having an exterior surface configured for close fitting receipt within the lobe, the vessel being removably mounted to the footing.

26. The centrifuge rotor of claim 23 wherein the belt is overlaid upon itself to define a plurality of plies over the hub and wherein the majority of the fibers forming the belt extend longitudinally thereof.

27. The centrifuge rotor of claim 24 wherein the belt is overlaid upon itself to define a plurality of plies over the hub. and wherein the majority of the fibers forming the belt extend longitudinally thereof.

28. The centrifuge rotor of claim 25 wherein the belt is overlaid upon itself to define a plurality of plies over the hub, and wherein the majority of the fibers forming the belt extend longitudinally thereof.

29. The centrifuge rotor of claim 25 wherein the vessel is movable with respect to the footing along an interface defined therebetween.

30. The centrifuge rotor of claim 2 wherein the textile structure takes the form of a braid.

31. The centrifuge rotor of claim 3 wherein the textile structure takes the form of a braid.

32. The centrifuge rotor of claim 4 wherein the textile structure takes the form of a braid.

33. The centrifuge rotor of claim 30 wherein the braid is defined by a plurality of cords each extending substantially radially across the hub in generally parallel relationship with the other cords, the radially outer ends of the cords being braided together to define the socket.

34. The centrifuge rotor of claim 31 wherein the braid is defined by a plurality of cords each extending substantially radially across the hub in generally parallel relationship with the other cords, the radially outer ends of the cords being braided together to define the socket.

35. The centrifuge rotor of claim 32 wherein the braid is defined by a plurality of cords each extending substantially radially across the hub in generally parallel relationship with the other cords, the radially outer ends of the cords being braided together to define the socket.

36. The centrifuge rotor of claim 33 wherein the socket also includes a helper yarn braided with cords.

37. The centrifuge rotor of claim 34 wherein the socket also includes a helper yarn braided with cords.

38. The centrifuge rotor of claim 35 wherein the socket also includes a helper yarn braided with cords.

39. The centrifuge rotor of claim 33 wherein the cords are consolidated at a point radially outwardly of the socket.

40. The centrifuge rotor of claim 34 wherein the cords are consolidated at a point radially outwardly of the socket.

41. The centrifuge rotor of claim 33 wherein the cords are braided back onto themselves in the region of the socket.

42. The centrifuge rotor of claim 34 wherein the cords are braided back onto themselves in the region of the socket.

43. The centrifuge rotor of claim 32 wherein the force transmitting arrangement comprises a saddle having grooves therein: and wherein the braid is defined by a cord which loops around the grooves in the saddle

44. The centrifuge rotor of claim 43 wherein the cord is terminated by an eyelet which is received in one of the grooves in the saddle.

45. The centrifuge rotor of claim 44 wherein the eyelet is defined by an eye splice.

46. The centrifuge rotor of claim 2 further a second carrier disposed in an overlying layered relationship with respect to the first carrier.

47. The centrifuge rotor of claim 3 further a second carrier disposed in an overlying layered relationship with respect to the first carrier.

48. The centrifuge rotor of claim 4 further a second carrier disposed in an overlying layered relationship with respect to the first carrier.

49. A swinging bucket centrifuge rotor for exposing a sample to a centrifugal force field comprising:
a central hub connectable to a source of motive energy for rotating the hub about an axis of rotation:
a sample carrier connectable to the hub, the carrier itself comprising: a woven belt of a high tensile strength fibers formed into a loop centered on the hub to define a first and a second lobe at each radial end of the carrier: a footing having an exterior surface configured for close fitting receipt within each lobe; and a vessel removably mounted to each footing, each vessel being adapted to receive a sample therein:
the sample carrier having flexibly deformable regions disposed intermediate the hub and the radially outer ends of each lobe, the carrier being adapted to accommodate by flexible deformation movement of the vessel in response to centrifugal force from a fist, rest, position in which the axis of the vessel is substantially parallel to the axis of rotation to a second, operational, position in which the axis of the vessel is substantially perpendicular to the axis of rotation.

50. The centrifuge rotor of claim 49 wherein the belt is woven with the majority of the fibers thereof extending longitudinally of the belt.

51. The swinging bucket rotor of claim 50 wherein the vessel is movable with respect to the footing along an interface defined therebetween.

52. A swinging bucket centrifuge rotor for exposing a sample to a centifugal force field comprising:
a hub connectable to a source of motive energy for rotating the hub about an axis of rotation; and a sample carrier connectable to the hub. the sample carrier comprising a braided cord having an eyelet at each end thereof, each eyelet surrounding a saddle member, the saddle being adapted to receive a vessel therein, the braided cord being looped about the saddle to form a structure having a flexibly deformable region disposed intermediate the hub and the saddle, the carrier being adapted to accommodate by flexible deformation movement of the vessel in response to centrifugal force from a first, rest, position in which the axis of the vessel is substantially parallel to the axis of rotation to a second, operational, position in which the axis of the vessel is substantially perpendicular to the axis of rotation.

53. The centrifuge rotor of claim 52 wherein each eyelet is defined by an eye splice.

54. A swinging bucket centrifuge rotor for exposing a sample to a centrifugal force field comprising:
a hub connectable to a source of motive energy for rotating the hub about an axis of rotation;
a sample carrier connectable to the hub, the carrier comprising a plurality of cords each extending substantially radially across the hub in a generally parallel relationship with the other cords, the radially outer ends of the cords being braided together to define a socket adapted to receive a sample therein:
the carrier having a flexibly deformable region intermediate the hub and the socket, the carrier being adapted to accommodate by flexible deformation movement from a first, rest, position in which the axis of the radially outer portion of the carrier is substantially parallel to the axis of rotation to a second, operational, position in which the axis of the radially outer portion of the carrier is substantially perpendicular to the axis of rotation.

55. The centrifuge rotor of claim 54 wherein the free ends of the cords radially outwardly of the socket are consolidated together.

56. The centrifuge rotor of claim 54 wherein the free ends of the cords are braided back into the socket.

57. A swinging bucket centrifuge rotor foe exposing a sample to a centrifugal force field comprising:
a hub connectable to a source of motive energy for rotating the hub about an axis of rotation; and a sample carrier connectable to the hub, the sample carrier comprising a central web portion having a plurality of sockets radiating therefrom. a flexibly deformable region being defined intermediate the web and each socket:
the carrier being adapted to accommodate, by flexible deformation movement of the socket from a first, rest, position in which the axis of the socket is substantially parallel to the axis of rotation to a second, operational, position in which the axis of the socket is substantially perpendicular to the axis of rotation.

58. A swinging bucket centrifuge rotor for exposing a sample to a centrifugal force field comprising:

a central hub connectable to a source of motive energy for rotating the hub about an axis of rotation;
a sample carrier flexibly connected to the hub, the sample carrier being adapted to support the sample during movement of the same in response to centrifugal force from a first, rest, position in which the axis of the carrier is substantially parallel to the axis of rotation to a second position in which the axis of the carrier is substantially perpendicular to the axis of rotation:
a cap assembly mountable to the rotor for rotation therewith, the cap assembly being responsive to centrifugal force as the rotor is spun by moving from an initial to a final position to permit the carrier to move from the first to the second position, the cap assembly being further responsive to gravity as the rotor slows to move toward the initial position, the cap being arranged to interact with the sample carrier as the cap responds to gravity thereby to assist in the restoration of the carrier to the first position.

59. The centrifuge rotor of claim 58 wherein the cap assembly comprises:
a central disk; and a skirt portion depending from the periphery of the core, the skirt being arranged to interact with the sample carrier as the cap responds to gravity to assist in restoring the carrier to the first position.

60. The centrifuge rotor of claim 59 wherein the hub has a central post upstanding therefrom, the post having a pivotable cam thereon and wherein the disk has a cam follower surface thereon engageable with the cam, the cam responding to centrifugal force by pivoting radially outwardly to engage the follower surface on the disk and thereby displace the disk and the skirt attached thereto from the initial to the final position.

61. The centrifuge rotor of claim 58 wherein the hub has a central post upstanding therefrom, the post having a pivotable cam thereon and wherein the cap assembly has a cam follower surface thereon engageable with the cam, the cam responding to centrifugal force by pivoting radially outwardly to engage the follower surface on the cap assembly and thereby displace the cap assembly from the initial to the final position.

62. The centrifuge rotor of claim 59 wherein the hub has a core attached thereto, the core having a radially outwardly extending trackway therein, a lug being movably disposed within the trackway, the disk having an arm thereon, a portion of the arm extending through the trackway, the lug being movable within the trackway in response to centrifugal force to engage against the arm on the core to thereby displace the disk and the skirt attached thereto from the initial to the final position.

63. The centrifuge rotor of claim 58 wherein the hub has a core attached thereto, the core having a radially outwardly extending trackway therein.

a lug being movably disposed within the trackway, the cap assembly having an arm thereon, a portion of the arm extending through the trackway, the lug being movable within the trackway in response to centrifugal force to engage against the arm on the cap assembly to thereby displace the cap assembly from the initial to the final position.

64. The centrifuge rotor of claim 58 wherein the cap assembly comprises a resilient arm connected to the hub with the free end of the arm engageable with the carrier, the arm being responsive to centrifugal force by deflecting from the initial to the final positions and, as the rotor slows, being also responsive to its resiliency to assist in the restoration of the carrier to the first position.

65. The centrifuge rotor of claim 59 wherein the hub has a hollow central post upstanding therefrom, a ribbon lifting element disposed within the hollow post, the lifting element being connected at one end to the disk, the other end of the ribbon element being disposed in a centrifugal force responsive orientation such that the ribbon element responds to centrifugal force to impose a lifting force on the disk and the skirt attached thereto to thereby displace the same from the initial to the final position.

66. The centrifuge rotor of claim 58 wherein the hub has a hollow central post upstanding therefrom, a ribbon lifting element disposed within the hollow post, the lifting element being connected at one end to the cap assembly, the other end of the ribbon element being disposed in a centrifugal force responsive orientation such that the ribbon element responds to centrifugal force to impose a lifting force on the cap assembly to thereby displace the same from the initial to the final position.

67. The centrifuge rotor of claim 59 wherein the skirt has an even number of scallops arranged into pairs, the number of pairs of scallops corresponding to the number of carriers of the rotor.

68. The centrifuge rotor of claim 60 wherein the skirt has an even number of scallops arranged into pairs, the number of pairs of scallops corresponding to the number of carriers on the rotor.

69. The centrifuge rotor of claim 62 wherein the skirt has an even number of scallops arranged into pairs, the number of pairs of scallops corresponding to the number of carriers on the rotor.

70. The centrifuge rotor of claim 65 wherein the skirt has an even number of scallops arranged into pairs, the number of pairs of scallops corresponding to the number of carriers on the rotor.

71. The centrifuge rotor of claim 59 wherein a first and a second carrier are layered accross the hub;
and wherein the skirt has an even number of scallops arranged in pairs, the number of pairs of scallops corresponding to the number of carriers on the rotor.
the height of each scallop in one pair as measured from a reference baseline being greater than the height of each scallop in the second pair.

72. The centrifuge rotor of claim 60 wherein a first and a second carrier are layered across the hub:
and wherein the skirt has an even number of scallops arranged in pairs, the number of pairs of scallops corresponding to the number of carriers on the rotor.
the height of each scallop in one pair as measured from a reference baseline being greater than the height of each scallop in the second pair.

73. The centrifuge rotor of claim 62 wherein a first and a second carrier are layered across the hub:
and wherein the skirt has an even number of scallops arranged in pairs, the number of pairs of scallops corresponding to the number of carriers on the rotor, the height of each scallop in one pair as measured from a reference baseline being greater than the height of each scallop in the second pair.

74. The centrifuge rotor of claim 65 wherein a first and a second carrier are layered across the hub;
and wherein the skirt has an even number of scallops arranged in pairs, the number of pairs of scallops corresponding to the number of carriers on the rotor, the height of each scallop in one pair as measured from a reference baseline being greater than the height of each scallop in the second pair.