The present invention relates generally to centrifuge rotors and, more particularly, to a fixed-angle rotor configured to support samples within a centrifuge.
Centrifuge rotors are typically used in laboratory centrifuges to hold samples during centrifugation. While centrifuge rotors may vary significantly in construction and in size, one common rotor structure is the fixed angle rotor having a solid rotor body with a plurality of cell hole cavities distributed circumferentially within the rotor body and arranged symmetrically about an axis of rotation. Samples are placed in the cavities, allowing a plurality of samples to be subjected to centrifugation.
Conventional fixed angle centrifuge rotors may be made from metal or various other materials. However, a known improvement is to construct a centrifuge rotor by a compression molding and filament winding process wherein the rotor is fabricated from a suitable material such as composite carbon fiber. For example, a fixed angle centrifuge rotor may be compression molded from layers of resin-coated carbon fiber laminate material. Examples of fixed angle composite centrifuge rotors are described in U.S. Pat. Nos. 5,833,908, 6,056,910, 6,296,798, 8,147,392, and 8,273,202, each disclosure of which is expressly incorporated herein by reference in its entirety.
Because centrifuge rotors are commonly used in applications where the rotational speed of the centrifuges may exceed hundreds or even thousands of rotations per minute, it is important that centrifuge rotors are formed with structure designed to withstand the stresses and strains experienced during the high speed rotation of the loaded rotor. An improvement for providing structural rigidity to the rotor body during centrifugation is described in U.S. Pat. No. 8,323,169 (also owned by the common assignee), the disclosure of which is expressly incorporated herein by reference in its entirety. In that improvement, a pressure plate is coupled to a bottom portion of the rotor body, such that the pressure plate supports the tubular cavities during rotation, thereby minimizing the likelihood of rotor failure.
While a primary source of stresses and strains experienced by a rotor during centrifugation includes outwardly directed centrifugal forces exerted by loaded cavities, an additional source is torque exerted by the rotating centrifuge spindle. More specifically, a central portion of the rotor where a rotor hub couples to the centrifuge spindle generates high degrees of torque during rotation of the rotor, particularly during rotational acceleration and deceleration. This torque results in high degrees of concentrated stress on various components of the rotor. Whereas performance capabilities of conventional rotors may be limited by their ability to accommodate such torque and resulting stress in addition to that caused by centrifugal forces, a need exists for centrifuge rotors having improved structural rigidity for mitigating the stresses and strains caused by various sources, including torque, during centrifugation.
The present invention overcomes the foregoing and other shortcomings and drawbacks of centrifuge rotors heretofore known for use for centrifugation. While the invention will be discussed in connection with certain embodiments, it will be understood that the invention is not limited to these embodiments. On the contrary, the invention includes all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention.
In one embodiment, a fixed angle centrifuge rotor includes a rotor body having a circumferential sidewall and a plurality of circumferentially spaced tubular cavities. Each tubular cavity has an open end and a closed end, and is configured to receive a sample container therein. The rotor further includes a pressure plate operatively coupled to the rotor body so that the pressure plate, in combination with the plurality of tubular cavities and the circumferential sidewall of the rotor body, define a hollow chamber within the rotor. The rotor further includes a plurality of elongated torque transfer members supported by the rotor body. Each of the plurality of torque transfer members has a first end located between a respective pair of adjacent tubular cavities, and extends radially inward in a direction toward a rotational axis of the rotor.
In another embodiment, a fixed angle centrifuge rotor includes a rotor body having a circumferential sidewall and a plurality of circumferentially spaced tubular cavities. Each tubular cavity has an open end and a closed end, and is configured to receive a sample container therein. The rotor further includes a plurality of pockets, each being located between a respective pair of adjacent tubular cavities. The rotor further includes a pressure plate operatively coupled to the rotor body so that the pressure plate, in combination with the plurality of tubular cavities and the circumferential sidewall of the rotor body, define a hollow chamber within the rotor. A plurality of circumferentially spaced upstanding tabs is supported by the pressure plate. Each of the plurality of tabs is received in a respective one of the plurality of pockets.
In another embodiment, a method is provided for manufacturing a centrifuge rotor. The method includes forming a rotor body having a circumferential sidewall and a plurality of circumferentially spaced tubular cavities. Each tubular cavity has an open end and a closed end, and is configured to receive a sample container therein. The method further includes operatively coupling a pressure plate having a plurality of circumferentially spaced upstanding tabs to the rotor body such that each tab is received in a respective pocket between a respective pair of adjacent tubular cavities.
In another embodiment, a method for manufacturing a centrifuge rotor includes forming a rotor body having a circumferential sidewall and a plurality of circumferentially spaced tubular cavities. Each of the tubular cavities has an open end and a closed end, and is configured to receive a sample container therein. The method further includes forming a plurality of elongated torque transfer members on the rotor body such that each of the torque transfer members has a first end located between a respective pair of adjacent tubular cavities and extends radially inward in a direction toward a rotational axis of the rotor.
In yet another embodiment, a fixed angle centrifuge rotor includes a plurality of tubular cavities spaced circumferentially about a rotational axis of the rotor. Each tubular cavity has an open end and a closed end, and is configured to receive a sample container therein. The rotor further includes an annular containment groove disposed above and circumferentially surrounding the plurality of tubular cavities. The annular containment groove has an upper reentrant portion in which a profile of the groove curves radially inward toward the rotational axis and axially downward toward the plurality of tubular cavities. The annular containment groove, in combination with the upper reentrant portion, is configured to capture and retain stray material within the rotor during rotation of the rotor.
Various additional features and advantages of the invention will become more apparent to those of ordinary skill in the art upon review of the following detailed description of the illustrative embodiments taken in conjunction with the accompanying drawings.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate certain embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below, serve to explain the invention.
Referring now to the figures, and in particular to
As shown in
As shown in
The elongated reinforcement 26, which may be a helical winding, extends continuously around a generally smooth, exterior surface 28 of the circumferentially-extending sidewall 20. As used herein, the term “generally smooth” is intended to describe a surface 28 that does not have a stepped configuration, and is generally free of corners or sharp edges. In this regard, the above-defined term is not intended to define the surface roughness of the surface 28. The rotor body 12 may be formed such that the generally smooth exterior surface 28 requires no additional machining or finishing prior to the application of the reinforcement 26. In one embodiment, the rotor body 12 may be formed using the methods disclosed in U.S. Pat. Nos. 8,147,392 and 8,273,202, incorporated by reference above. The rotor body 12 may be formed of any suitable material or combination of materials, including carbon fiber, for example.
As best shown in
The illustrated embodiment of the rotor 10 includes ten tubular cell hole cavities 24, which may be of any suitable cavity volume. For example, in one embodiment, each of the ten tubular cavities 24 may be sized to receive a sample container having an internal volume of approximately 1,000 ml. Persons skilled in the art will appreciate that a rotor in accordance with the principles of the invention may be formed with any suitable number of tubular cavities 24, wherein each cavity 24 defines any suitable cavity volume. For example, in one alternative embodiment, described in greater detail below in connection with
Each of the tubular cell hole cavities 24 extends from the top wall 22 into an interior 30 of the rotor body 12, in a direction generally toward the lower end 12b of the rotor body 12 and angularly relative to the rotational axis A. As used herein, the term “interior” refers to the general portion of a centrifuge rotor that is enclosed by and disposed radially inward of the corresponding circumferential sidewall of the rotor body. Additionally, as used herein, the term “tubular” refers to cavities having any suitable cross-sectional shape, such as rounded shapes (e.g., oval, circular or conical), quadrilateral shapes, regular polygonal shapes, or irregular polygonal shapes, for example. Accordingly, this term is not intended to be limited to the generally circular cross-sectional profile of the exemplary tubular cavities illustrated in the figures.
Each tubular cavity 24 includes an open end 34 at the top wall 22 and an oppositely disposed closed end 36 oriented toward the lower end 12b. Each cavity 24 is defined by a sidewall 38 and a bottom wall 39, and is suitably sized and shaped to receive a sample container therein (not shown) for centrifugation about rotational axis A. Each cavity sidewall 38 includes an inner face 38a that receives and supports the respective sample container, and an outer face 38b that faces generally toward the interior 30 of the rotor body 12.
As best shown in
Referring to
As shown, the rotor 10 may include ten torque transfer members 50, such that one member 50 extends between each adjacent pair of tubular cavities 24. As described above, the rotor 10 may be formed with any suitable number of tubular cavities 24. Accordingly, the rotor 10 may be formed with any suitable number of torque transfer members 50, to maintain any desired ratio of torque transfer members 50 to tubular cavities 24. For example, as described below in connection with the alternative embodiment shown in
The rotor 10 may further include a torque transfer ring 60 supported by the rotor body 12, and which may be operatively coupled to the central interior portion 51 of the rotor body 12, according to one embodiment. As shown, the torque transfer ring 60 extends from a bottom surface of the top wall 22 into the interior 30, and thus into the hollow chamber 42. As shown, the torque transfer ring 60 is centrally located about the rotational axis A such that the second end 54 of each torque transfer member 50 extends radially toward and operatively couples to the torque transfer ring 60. In one embodiment, the torque transfer members 50 and torque transfer ring 60 may be formed integrally as one piece with the rotor body 12, including the top wall 22, the central interior portion 51, and the sidewalls 38 of the tubular cavities 24. In an alternative embodiment, either or both of the torque transfer members 50 and the torque transfer ring 60 may be releasably coupled to the rotor body 12.
Additionally, as shown in
As best shown in
The torque transfer members 50 extend generally axially from a bottom surface of the top wall 22 into the interior 30, and thus into the hollow chamber 42, such that the sidewalls 62, 64 define an axial thickness of a respective torque transfer member 50. As best shown in
The torque transfer members 50 and torque transfer ring 60 may be formed of any suitable material or combination of materials. For example, the torque transfer members 50 and/or the torque transfer ring 60 may be formed of a carbon fiber composite having an optimized fiber orientation. In an alternative embodiment, the torque transfer members 50 and/or the torque transfer ring 60 may be formed of a metal.
Referring to
The pressure plate 16 may be operatively coupled to the lower end 12b of the rotor body 12, such that the conical wall portion 70 is received within the interior 30 of the rotor body 12 and engages a radially inward-facing side portion of each of the outer faces 38b of the tubular cavities 24. The pressure plate 16 may be seated against the rotor body 12 such that the top wall portion 72 remains axially spaced from the top wall 22, the torque transfer members 50, and torque transfer ring 60 supported by the top wall 22. Thereby, the coupling of the pressure plate 16 to the rotor body 12 fully defines the hollow chamber 42, including the pockets 40. In particular, the hollow chamber 42 is bordered by the circumferential sidewall 20, the top wall 22, and the outer faces 38b of the rotor body 12, and by the conical wall portion 70, the top wall portion 72, and the bottom wall portion 74 of the pressure plate 16.
Accordingly, in the illustrated embodiment of rotor 10, a substantial portion of each of the outer faces 38b of the tubular cavities 24 is surrounded by hollow space including the hollow chamber 42 and a respective pair of adjacent pockets 40. As used herein, the term “substantial,” when used to describe the portion of an outer face of a tubular cavity surrounded by hollow space, is intended to describe an embodiment where at least about 40%, and preferably between about 40% and about 60%, of a particular outer face of a tubular cavity is surrounded by hollow space.
The annular bottom wall portion 74 of the pressure plate 16 includes a plurality of circumferentially-spaced depressions 76, and the conical wall portion 70 includes a corresponding plurality of circumferentially-spaced scallops 77 that extend downwardly toward and open to the depressions 76. In particular, the pressure plate 16 preferably includes one depression 76 and one scallop 77 for each tubular cavity 24 (i.e., ten depressions 76 and ten scallops 77 for the embodiment shown in
With continued reference to
The pressure plate 16 may further include a plurality of circumferentially-spaced ribs 78 extending angularly between the conical upstanding wall portion 70 and the annular bottom wall portion 74. In the embodiment shown, a rib 78 is provided between each pair of adjacent depressions 76 and scallops 77. When the pressure plate 16 is coupled to the rotor body 12, each rib 78 extends between a respective pair of adjacent tubular cavities 24, and partially into the respective pocket 40. The ribs 78 operate in a brace-like manner to provide additional structural support to the pressure plate 16, and thus also to the rotor body 12, during high-speed rotation of the rotor 10.
The pressure plate 16 may further include a plurality of circumferentially-spaced upstanding tabs 80 extending between the depressions 76, as best shown in
Coupling of the pressure plate 16 to the rotor body 12 may be facilitated by a fastener, such as a retaining nut 90, for example. In the embodiment shown, the retaining nut 90 threadedly engages an externally threaded portion 92 of a rotor hub 94. As described in greater detail below, the rotor hub 94 facilitates engagement of the rotor 10 with a centrifuge spindle (not shown) of the centrifuge 13 to enable high-speed rotation of the rotor 10 during centrifugation. Engagement of the nut 90 is effected from an underside of pressure plate 16, with such engagement thereby operatively securing the rotor hub 94 to the top wall portion 72 of the pressure plate 16. The nut 90 may include two or more circumferentially-spaced tool-engagement recesses 91 (
Coupling of the pressure plate 16 to the rotor body 12 may be further enhanced by compression-molding these two components together with the elongated reinforcement 26. In one embodiment, as disclosed in U.S. Pat. Nos. 8,147,392, 8,273,202, and 8,323,169, incorporated by reference above, the reinforcement 26 may be applied by helically winding a continuous strand of high strength fiber, such as a single tow or strand of carbon fiber (e.g., a resin-coated carbon fiber), around at least a portion of the exterior surface 28 of rotor body 12, and over exposed radially outer portions of the pressure plate 16. In particular, as disclosed in the above identified patents, the strand may be tightly wound repeatedly around the rotor body 12 and the pressure plate 16 such that the strand overlaps itself to define crossing points at regions that experience greatest stress during centrifugation, thereby forming a plurality of reinforcement layers 26. Persons of ordinary skill in the art will appreciate that various alternative methods of coupling the pressure plate 16 to the rotor body 12 may be used.
As described above, the rotor 10 of the illustrated embodiment includes a rotor insert 96 configured to receive and threadedly engage the rotor hub 94. As shown best in
The rotor insert 96 may be formed of any suitable material, such as a metal, and may be molded into the rotor body 12 during body formation, as disclosed by U.S. Pat. Nos. 8,147,392 and 8,273,202, incorporated by reference above. Additionally, as shown in
The rotor body 12, the rotor lid 14, and the pressure plate 16 may be formed using the compression molding methods disclosed in U.S. Pat. Nos. 8,147,392 and 8,273,202, incorporated by reference above. More specifically, a first mold (not shown) may be used having cavities that define the contours of the outer surfaces of the rotor body 12. The first mold may also include a centrally located mold core that supports the rotor insert 96. A plurality of disk-shaped woven fiber sheets, pre-impregnated with an epoxy matrix, may be stacked vertically within the first mold and around the mold core, the stacked sheets progressively varying in diameter such that their outer edges define the contoured circumferential sidewall 20 of the rotor body 12 being formed.
The woven fiber sheets, which may be carbon fiber sheets, may include fibers woven in two transverse directions, and the sheets may include circumferentially spaced circular openings for defining the tubular cavities 24. As the woven fiber sheets are stacked, each successive sheet may be oriented such that the woven fibers forming the sheet are rotated (about the rotational axis of the rotor body 12 being formed) approximately 45 degrees relative to the woven fibers forming the immediately adjacent woven sheet positioned beneath it. After stacking the woven fiber sheets, the tubular cavities 24 may be further defined by inserting pre-formed tubular inserts into the angled apertures defined by the circular openings in the stacked woven sheets. Each tubular insert may be formed by a corresponding plurality of woven fiber sheets, layered radially about a longitudinal axis of the tubular insert. Heat and pressure may then be applied to the first mold containing the stacked woven fiber sheets to form the rotor body 12, the torque transfer members 50 and the torque transfer ring 60. Using similar compression molding techniques, a second mold may be used to form the pressure plate 16, and a third mold may be used to form the rotor lid 14, the pressure plate 16 and rotor lid 14 each being formed of a corresponding plurality of stacked woven fiber sheets.
In use, the rotor 10, including the rotor hub 94 threadedly engaged with the rotor insert 96 and the retaining nut 90, is mounted and coupled to a centrifuge spindle (not shown) of the centrifuge 13, such that a projecting portion of the spindle is received within the rotor hub 94. As shown in
A lid screw retainer 118 may be coupled to the hub retainer 112, for example by threaded engagement, and be configured to threadedly receive a lid screw 120 for securing the rotor lid 14 to the rotor body 12. As shown in
Furthermore, in the embodiment shown, the rotor lid 14 may include a sealing element 122, and the lid screw 120 may include a sealing element 124. The sealing elements 122, 124 may be o-rings, for example, and further facilitate coupling of the rotor lid 14 to the rotor body 12, and the lid screw 120 to the lid screw retainer 118, respectively. While the embodiment shown herein illustrates one coupling method for securing the rotor lid 14 to the rotor body 12, persons skilled in the art will appreciate that various alternative coupling methods may also be used.
After mounting the rotor 10 to the centrifuge spindle, the centrifuge spindle may then be actuated to drive the rotor 10 into high-speed, centrifugal rotation. During rotation of the rotor 10 of the illustrated embodiment, the rotating spindle exerts a torque on the rotor hub 94, which in turn exerts a torque on the rotor insert 96, which in turn exerts a torque on the central interior portion 51 and additionally the torque transfer ring 60. The torque transfer ring 60 then transfers torque radially outward through the torque transfer members 50. More specifically, the torque transfer members 50, in addition to central interior portion 51, transfer the torque radially outward to the tubular cavities 24 and the sample containers held therein. Accordingly, the torque applied to the tubular cavities 24 is transferred through not just the central interior portion 51, but also through the torque transfer ring 60 and the torque transfer members 50. Thus, provision of the torque transfer ring 60 and the torque transfer members 50 advantageously provides the rotor 10 with added structural rigidity for withstanding the high degrees of torque experienced during high-speed rotation. Additionally, the circumferentially spaced depressions 76, ribs 78, and upstanding tabs 80 formed on the pressure plate 16 provide additional structural rigidity to the tubular cavities 24, and thus to the rotor body 12 as a whole, during high-speed rotation.
Referring to
The rotor 210 further includes an elongated reinforcement 226, which may be applied using similar methods described above in connection with reinforcement 26 such that it extends continuously around the rotor body 212 and radially outer portions of the pressure plate 216, thereby facilitating the coupling of the pressure plate 216 to the rotor body 212. The elongated reinforcement 226 may also extend above the upper end 212a of the rotor body 212 to form an upper reinforcement portion 226a that is configured to receive and support an outer circumferential edge of the rotor lid.
Referring to
The liquid containment groove 227 may be formed using an annular groove tool 229 having multiple portions, as shown schematically in
Following formation of the rotor body 212, for example using the compression molding methods described above, the groove tool 229 may be positioned above the upper end 212a of the rotor body 212. The strand forming the elongated reinforcement 226, as described above in connection with reinforcement 26, may then be wound around the groove tool 229, in combination with winding around the rotor body 212 and the pressure plate 216, to form the upper reinforcement portion 226a. Following formation of the upper reinforcement portion 226a, the groove tool 229 may then be disassembled sequentially, for example by first removing the lower tool portion 229b and then removing the upper tool portion 229a, as shown by the directional arrows in
As shown in
The scalloped configuration of the top wall 222, as described above, provides several advantages. For example, the top wall 222 may be formed using less material, thereby minimizing weight of the rotor body 212 and a minimizing a rotational moment of inertia of the centrifuge rotor 210 about the rotational axis A. Additionally, this scalloped configuration serves to expose upper portions of the sample containers facing inwardly toward the rotational axis A near the recessed lower region 222b. These exposed upper portions, which may be portions of the sample container closures, may be easily gripped by an operator for removal of the sample containers from their respective tubular cavities 224. Furthermore, the scalloped configuration of top wall 222 serves to minimize a wall thickness of each sloped connecting portion 222c in a circumferential direction, thereby permitting the upper portions of the sample containers to be positioned closer to the rotation axis A, and thus provide a more compact design.
In this embodiment, the rotor body 212 includes six tubular cell hole cavities 224, each of which may be sized to receive a sample container having an internal volume of approximately 2,000 ml, for example. As described above in connection with centrifuge rotor 10, alternative embodiments of centrifuge rotor 210 may include any suitable number of tubular cavities 224, wherein each cavity 224 defines any suitable cavity volume. In such alternative embodiments, additional features of the rotor 210 may be modified in quantity, size, and/or position as appropriate.
Each of the tubular cell hole cavities 224 extends from the top wall 222 into an interior 230 of the rotor body 212, in a direction generally toward the lower end 212b of the rotor body 212 and angularly relative to the rotational axis A. Each tubular cavity 224 includes an open end 234 at the top wall 222 and an oppositely disposed closed end 236 oriented toward the lower end 212b. Each tubular cavity 224 is defined by a sidewall 238 and a bottom wall 239, and is suitably sized and shaped to receive a sample container therein (not shown) for centrifugation about rotational axis A. Each cavity sidewall 238 includes an inner face 238a that receives and supports the respective sample container, and an outer face 238b that faces generally toward the interior 230 of the rotor body 212.
As best shown in
Referring to
As shown, the rotor 210 may include six torque transfer members 250, such that one member 250 extends between each adjacent pair of tubular cavities 224. As described above, the rotor 210 may be formed with any suitable number of tubular cavities 224. Accordingly, the rotor 210 may be formed with any suitable number of torque transfer members 250, to maintain any desired ratio of torque transfer members 250 to tubular cavities 224.
The rotor 210 may further include a torque transfer ring 260 supported by the rotor body 212, and which may be operatively coupled to the central interior portion 251 of the rotor body 212, according to one embodiment. As shown, the torque transfer ring 260 extends from a bottom surface of the top wall 222 into the interior 230, and thus into the hollow chamber 242. As shown, the torque transfer ring 260 is centrally located about the rotational axis A such that the second end 254 of each torque transfer member 250 extends radially toward and operatively couples to the torque transfer ring 260. In one embodiment, the torque transfer members 250 and torque transfer ring 260 may be formed integrally as one piece with the rotor body 212, including the top wall 222, the central interior portion 251, and the sidewalls 238 of the tubular cavities 224. In an alternative embodiment, either or both of the torque transfer members 250 and the torque transfer ring 260 may be releasably coupled to the rotor body 212.
As shown in
As best shown in
The torque transfer members 250 extend generally axially from a bottom surface of the top wall 222 into the interior 230, and thus into the hollow chamber 242, such that each arcuate sidewall 262 defines an axial thickness of its respective torque transfer members 250. As best shown in
The torque transfer members 250 and torque transfer ring 260 may be formed of any suitable material or combination of materials. For example, the torque transfer members 250 and/or the torque transfer ring 260 may be formed of a carbon fiber composite having an optimized fiber orientation. In an alternative embodiment, the torque transfer members 250 and/or the torque transfer ring 260 may be formed of a metal.
Referring to
As shown in
As best shown in
As shown in
Similarly, the scallops 277 are configured to receive and engage, in abutting relationship, the outer faces 238b of the tubular cavities 224. In particular, the scallops 277 are suitably sized and shaped such that each scallop 277 substantially conforms to the curvature of a lower portion of a respective outer face 38b.
The pressure plate 216 may be mated with the rotor body 212 such that each depression 276 and corresponding scallop 277 jointly engage a respective tubular cavity 224. In this manner, the depressions 276 provide structural support to the tubular cavities 224, thereby providing rigidity during high-speed rotation of the rotor 10, while the scallops 277 assist in maintaining circumferential alignment of the pressure plate 216 relative to the rotor body 212. In an alternative embodiment, the pressure plate 216 may include a quantity of depressions that is less than the quantity of tubular cavities 224, where each depression is suitably sized and shaped to receive and engage two or more tubular cavities 224.
The pressure plate 216 may further include a plurality of circumferentially-spaced raised sections 279 disposed on the annular bottom wall portion 274. As best shown in
Coupling of the pressure plate 216 to the rotor body 212 may be achieved with the assistance of mechanical coupling components substantially similar to those described above in connection with centrifuge rotor 10. Additionally, coupling between the pressure plate 216 and rotor body 212 may be further enhanced by application of the elongated reinforcement 226, which may be applied to the rotor body 212 and pressure plate 216 in a manner substantially similar to that described above in connection with elongated reinforcement 26 of rotor 10.
The rotor body 212 further includes a rotor insert 296 provided within an internal pocket 300 of a central interior portion 251, as best shown in
The rotor insert 296 is located about the rotational axis A such that it extends through an opening 302 formed in the top wall 222, the central interior portion 251, and the torque transfer ring 260. The rotor insert 296 includes a plurality of alternating, radially extending long arms 304a and short arms 304b that are received within a corresponding plurality of alternating, radially extending long channels 306a and short channels 306b of the internal pocket 300. In one embodiment, the rotor 210 may be formed such that the number of arms 304a, 304b and respective channels 306a, 306b is equal to the number of tubular cavities 224. More specifically, the number of long arms 304a may be equal to one-half of the number of tubular cavities 224. For example, in the embodiment shown, the rotor 210 includes six tubular cavities 224 and a rotor insert 296 having three long arms 304a and three short arms 304b, and an internal pocket 300 having three long channels 306a and three short channels 306b for receiving the respective arms 304a, 304b. Persons skilled in the art will appreciate that alternative embodiments of the rotor 210 may be formed with any desired ratio of tubular cavities 224 to rotor insert arms 304a, 304b and corresponding pocket channels 306a, 306b. Additionally, in alternative embodiments, the rotor insert arms and corresponding pocket channels may be formed with any suitable shapes and sizes.
The rotor insert 296 may be formed of any suitable material, such as a metal. Additionally, the radially extending arms 304a, 304b may each include a respective aperture 298a, 298b extending axially therethrough. for weight reduction purposes, for example. Additionally, the rotor insert 296 may be molded into the rotor body 212 during body formation, as disclosed by U.S. Pat. Nos. 8,147,392 and 8,273,202, incorporated by reference above. During molding process, liquid adhesive may flow into and substantially fill each of the apertures 298a, 298b extending through the rotor insert 296. The adhesive may then cure to form solid columns 299a and 299b extending through the respective apertures 298a, 298b. The columns 299a, 299b may operate to securely retain the rotor insert 296 within the central interior portion 251, and to provide the rotor body 212 with additional structural rigidity.
The rotor body 212 and the pressure plate 216 may be formed using the compression molding methods described above in connection with centrifuge rotor 10 and the U.S. patents incorporated herein. Additionally, the assembled centrifuge rotor 210 may be mounted to a centrifuge spindle (not shown) of the centrifuge 13 in a manner similar to, and with coupling components similar to, those described above in connection with centrifuge rotor 10. In other embodiments, the rotor 210 may be fitted with any suitable coupling components for coupling the rotor insert 296 with any suitable centrifuge spindle.
After mounting the rotor 210 to the centrifuge spindle, the centrifuge spindle may then be actuated to drive the rotor 210 into high-speed, centrifugal rotation. During rotation of the rotor 210, the components thereof may operate in a manner similar to those described above in connection with rotor 10. In particular, a torque is transferred from the rotating rotor spindle to the rotor insert 96, which in turn exerts a torque on the central interior portion 251 and additionally the torque transfer ring 260. The torque transfer ring 260 then transfers torque radially outward through the torque transfer members 250. More specifically, the torque transfer members 250, in addition to central interior portion 251, transfer the torque radially outward to the tubular cavities 224 and the sample containers held therein. Accordingly, the torque applied to the tubular cavities 224 is transferred through not just the central interior portion 251, but also through the torque transfer ring 260 and the torque transfer members 250. Thus, provision of the torque transfer ring 260 and the torque transfer members 250 advantageously provides the rotor 210 with added structural rigidity for withstanding the high degrees of torque experienced during high-speed rotation. Additionally, the annular support ring 275, circumferentially spaced depressions 276, and raised sections 279 may provide additional structural rigidity to the tubular cavities 224, and thus to the rotor body 212 as a whole, during high-speed rotation.
While the present invention has been illustrated by the description of specific embodiments thereof, and while the embodiments have been described in considerable detail, it is not intended to restrict or in any way limit the scope of the appended claims to such detail. The various features discussed herein may be used alone or in any combination. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the scope or spirit of the general inventive concept.
The present application is a Divisional of co-pending U.S. Ser. No. 14/589,532, filed Jan. 5, 2015, the disclosure of which is hereby incorporated herein by reference in its entirety.
Number | Date | Country | |
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Parent | 14589532 | Jan 2015 | US |
Child | 16112986 | US |