Apparatus for centrifugation

Abstract

A centrifuge comprising a rotor (12) that can be driven to rotate during a centrifugation process, the rotor having an axis of rotation and an outer edge, the rotor having an opening for receiving a sample holder (1), the opening being formed in a first surface of the rotor and positioned between the axis of rotation and the outer edge, the opening having an inner surface in which the sample holder can be received, the opening having an end wall facing generally towards the axis of rotation, the rotor including a lip (21) overlapping a portion of the opening in the region of the end wall, the lip being spaced from the inner surface and defining an area between the inner surface and an underside of the lip.

Description

[Technical field]

[0001] The present application relates to an apparatus for centrifugation. [Background technology]

[0002] When a liquid sample is analyzed by centrifugation, the sample is typically first collected using a relatively small, handheld device such as a cuvette, which is then placed in a centrifuge for analysis.

[0003] Generally, a centrifuge includes a disk-shaped component that can be driven to spin at high speeds about an axis. The disk includes an opening for receiving a cuvette, and in all or most instances, when the cuvette is received in the opening, the sample chamber of the cuvette is aligned or substantially aligned with the radial axis of the disk. Subsequent rotation of the disk causes separation of different phases or substances within the liquid sample, as is known in the art. Summary of the Invention [Problem to be solved by the invention]

[0004] The object of the present invention is to provide an improved device for centrifugation, in particular one which can be more easily operated by non-professional users, more particularly users who may have reduced or impaired eyesight and / or dexterity. [Means for solving the problem]

[0005] Representative features Representative features are described in the following clauses, which may be combined independently or in any combination with one or more features disclosed in the text and / or drawings of this specification.

[0006] One aspect of the present application provides a centrifuge comprising a rotor that can be driven to rotate during a centrifugation process, the rotor having an axis of rotation and an outer edge, the rotor having an opening for receiving a sample holder, the opening formed in a first surface of the rotor and positioned between the axis of rotation and the outer edge, the opening having an inner surface in which the sample holder can be received, the opening having an end wall facing generally toward the axis of rotation, the rotor including a lip overlying a portion of the opening in the area of ​​the end wall, the lip being spaced from the inner surface and defining an area between the inner surface and an underside of the lip.

[0007] Advantageously, the opening has an inner end closest to the axis of rotation and an outer end closest to the outer edge, and the lip overlaps part of the opening at or near the outer end.

[0008] Preferably, the rotor has a first surface with the opening formed therein, and the inner surface is offset from the first surface of the rotor.

[0009] Advantageously, in the region of the lip, the lip is parallel or substantially parallel to the first surface of the rotor.

[0010] Advantageously, in the region of the lip, the upper surface of the lip is aligned or substantially aligned with the first surface of the rotor.

[0011] Preferably, the openings do not extend through the entire thickness of the rotor.

[0012] Conveniently, the first surface of the rotor is its upper surface.

[0013] Advantageously, the rotor has a lower surface, the thickness of the rotor being defined between the upper and lower surfaces.

[0014] Preferably, the lip is adjacent the end wall.

[0015] Conveniently, a deflection surface is formed extending between the end wall and the underside of the lip, the deflection surface being at an angle to both the end wall and the underside of the lip.

[0016] Advantageously, a deflection surface is formed extending between the end wall and the inner surface, the deflection surface being at an angle relative to both the end wall and the inner surface.

[0017] Preferably, in the region of the lip, the opening has a width and the lip extends completely or substantially completely across the width.

[0018] Advantageously, the length of the lip is at least 5% of the length of the opening.

[0019] Advantageously, the centrifuge further comprises a housing in which the rotor is mounted, and a drive mechanism for driving the rotational movement of the rotor.

[0020] Preferably, the centrifuge does not have a cover that is placed directly over the opening during the centrifugation process.

[0021] Another aspect of the invention provides a centrifugation device comprising a centrifuge according to any one of the above and a cuvette, the cuvette capable of being received within the opening.

[0022] Conveniently, the cuvette can be placed in an initial position within the opening by advancing it into the opening in a direction substantially perpendicular to the axis of rotation of the rotor, so that the cuvette is received in an area of ​​the opening that is not the area between the inner surface and the underside of the lip.

[0023] Advantageously, from the initial position, the cuvette can be moved, without being removed from the opening, in a direction passing from the axis of rotation of the rotor towards the outer edge of the rotor to a second position in which a portion of the cuvette is received in the area between the inner surface and the underside of the lip.

[0024] Preferably, when the cuvette is in the initial position, rotation of the rotor about the axis of rotation at a sufficient speed drives the cuvette to the second position.

[0025] Conveniently, the opening includes one or more finger holes which comprise an area of ​​the opening not occupied by the cuvette when the cuvette is received within the opening.

[0026] Advantageously, the finger hole comprises an area of ​​the opening that is not occupied by the cuvette either in the initial position or in the second position.

[0027] Preferably, the opening includes two finger holes, the finger holes extending from substantially opposite sides of the opening.

[0028] Conveniently, the or each finger hole extends from the opening in a direction substantially perpendicular to a direction passing from the axis of rotation of the rotor to the outer edge of the rotor.

[0029] Advantageously, the cuvette has one or more protruding ridges and the inner surface of the rotor has one or more corresponding grooves formed therein, the one or more grooves being received in the respective grooves when the cuvette is positioned in the first or second position.

[0030] Preferably, the cuvette can be slid against the inner surface from a first position to a second position, with the one or more grooves remaining within their respective grooves. [Brief description of the drawings]

[0031] In order that the invention may be more readily understood, embodiments will now be described, by way of example, with reference to the accompanying drawings, in which: [Figure 1] 1 shows a first cuvette suitable for use in the present invention. [Diagram 2] 2 shows a rotor embodying the present invention suitable for use with the cuvette of FIG. 1; [Diagram 3] FIG. 3 is a cross-sectional view of the rotor of FIG. 2. [Figure 4]3 at various stages of using a rotor with the cuvette of FIG. 1. [Diagram 5] 3 at various stages of using a rotor with the cuvette of FIG. 1. [Figure 6] 3 at various stages of using a rotor with the cuvette of FIG. 1. [Figure 7] 1 illustrates preferred features of the cuvette. [Figure 8] 1 illustrates preferred features of the cuvette. [Figure 9] 3 shows an alternative arrangement for the lip of the rotor of FIG. 2; [Figure 10] 1 shows a second cuvette suitable for use in the present invention. [Figure 11] 11 shows a receiving opening of a rotor embodying the invention suitable for use with the cuvette of FIG. 10; [Figure 12] 10 is shown within the receiving opening of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Referring initially to Figure 1, there is shown a cuvette 1 suitable for use in the present application. For the avoidance of doubt, embodiments of the present invention may work with many different cuvette designs and the present invention is not limited to use with a cuvette of the design shown in Figure 1.

[0033] The cuvette 1 has a generally flat, substantially planar body 2. The front end 3 has a pointed apex portion 4, the tip of which provides the cuvette tip 34. The rear end 5 of the cuvette 1 has a generally flat trailing edge 6.

[0034] The body 2 has a generally planar top surface 7 and an opposing bottom surface 8. Over most of the area of ​​the body 2, the top surface 7 and the bottom surface 8 are generally parallel to each other and are separated by a distance corresponding to the depth of the body 2.

[0035] In the example shown, the cuvette 1 has opposing side edges 32, 33 that are parallel or substantially parallel to one another. In this example, the body 2 of the cuvette 1 is generally rectangular except for a pointed apex portion 4. Where the edges meet one another, the cuvette 1 has rounded corners for ease of handling.

[0036] On either side of the body 2 near the front end 3 of the cuvette 1, a protrusion 9 extends upwardly and downwardly from the plane of the body 2. In the embodiment shown, each protrusion 9 takes the form of a ridge that protrudes from the top surface 7 or bottom surface 8 and is aligned or substantially aligned with a central longitudinal axis of the cuvette 1, which in the example shown passes midway or approximately midway between the side edges 32, 33 along the length of the cuvette 1 from the front end 3 to the rear end 5.

[0037] Each protrusion 9 has a shape that is generally semicircular when viewed in the plane of the body 2 of the cuvette 1. In the example shown, the protrusions 9 protruding from the top and bottom faces 7 and 8 on each side of the body 2 are aligned with each other, i.e. each protrusion 9 on the top face 7 is directly opposite a corresponding protrusion on the bottom face 8. However, this does not have to be the case.

[0038] In use, the tip 4 of the cuvette 1 is brought into contact with a sample of liquid, for example a drop of blood. The liquid is drawn into the cuvette 1 and, in a first example, is received in a collection chamber. The collection chamber is not directly visible in Figure 1, but a first window 10 positioned at or near the tip 4 allows a user of the cuvette 1 to easily view the liquid in the collection chamber.

[0039] In a preferred embodiment, the majority of the exterior of the cuvette 1 has a textured or matte finish for ease of handling, and the first window 10 is transparent or substantially transparent.

[0040] Upon centrifugation, liquid received in the collection chamber is directed into the analysis chamber, which is elongated and preferably has a constant width and depth along its length. Again, the analysis chamber is not directly visible in FIG. 1, but a second window 11 allows a user of the cuvette 1 to view the liquid within the analysis chamber. The second window 11 is preferably elongated and generally aligned with a central longitudinal axis of the cuvette 1. Like the first window 10, the second window 11 is transparent or substantially transparent.

[0041] Referring to Figure 2, a portion of the disk 12 is shown. As will be described in more detail below, the disk 12 is the rotor of a centrifuge. The centrifuge includes other components (not shown) such as a housing in which the disk 12 is mounted or other components (not shown) that drive the rotational movement of the disk. The centrifuge also preferably includes an analysis mechanism for analyzing or otherwise obtaining data about the sample. The analysis mechanism may include, for example, one or more light sources and one or more light sensors.

[0042] In use, the disc 12 rotates about a central axis (not shown). For clarity, only a portion of the edge of the disc 12 is shown.

[0043] The disk 12 has a receiving opening 14 formed in its upper surface 13. In a preferred embodiment of the invention, the receiving opening 14 does not extend through the entire thickness of the disk 12.

[0044] The receiving opening 14 is adapted to receive the cuvette 1 shown in FIG.

[0045] Next, the shape of the receiving opening 14 will be described. Those skilled in the art will appreciate that some aspects of the shape are determined by the shape of the cuvette 1. As mentioned above, the present invention is not limited to the use of the cuvette shown in Figure 1, and if a cuvette of a different shape and / or design is used, the shape of the receiving opening 14 will vary accordingly.

[0046] An inner end 15 of the receiving opening 14 closest to the central axis of the disk 12 has a shape that at least approximately corresponds to the shape of the front end 3 of the cuvette 1. As can be seen in Figure 2, the inner end 15 has a shape that tapers towards a tip 16.

[0047] The receiving opening 14 extends from its inner end 15 toward its outer end 17, which is furthest from the axis of rotation and closest to the outer edge 18 of the disk 12, so that the receiving opening 14 has respective side edges 35, 36 (excluding the finger holes described below) and defines therebetween a width 19 which is the same as, approximately the same as, or slightly greater than the width of the body 2 of the cuvette 1.

[0048] Projecting outwardly from side edges 35, 36, respectively, of the receiving opening 14 are first and second finger holes 20. Each finger hole 20 takes the form of a region of the receiving opening 14 that extends laterally outward, and in the example shown in Figure 2, each finger hole 20 has a generally semicircular shape. In the example shown, the finger holes are opposed to one another in that they are the same distance or substantially the same distance from the axis of rotation of the disc 12.

[0049] Preferably, the two finger holes 20 are generally symmetrical, i.e., they are substantially mirror images of each other. However, this need not be the case.

[0050] The outer end 17 of the receiving opening 14, which is furthest from the axis of rotation of the disk 12, is provided with an overhanging lip 21, which will be described in more detail below.

[0051] The above-mentioned portions of the receiving opening 14 preferably have a substantially constant depth. The receiving opening 14 has an upwardly facing surface 26, which in the illustrated example is parallel or nearly parallel to the top surface 13 of the disk 12.

[0052] Towards the inner end 15 of the receiving opening 14, a pair of recessed grooves 22 are formed, one on each side of the receiving opening 14. The grooves 22 have a width and depth such that one of the projections 9 of the cuvette 1 can be received within each groove 22. The depth of each groove 22 is preferably sufficient to allow the projection 9 to be completely received in the groove 22 such that the body 2 of the cuvette 1 can be flat against the upper surface 26 of the receiving opening 14.

[0053] The length of the groove 22 is greater than the length of one of the protrusions 9. This means that when a protrusion 9 is received in one of the grooves 22, the cuvette 1 can slide relative to the disk 12 at least a certain distance in a direction parallel to the groove 22. The advantage of this will be explained in more detail below.

[0054] In the illustrated example, the analysis opening 47 is formed through the upwardly facing surface 26 of the receiving opening 14. The analysis opening 47 is formed through the entire thickness of the disk 12. The analysis opening 47 is preferably positioned such that when the cuvette 1 is placed in the receiving opening 14, the analysis opening 47 is aligned or substantially aligned with the second window 11 of the cuvette 1. The presence of the analysis opening 47 allows for analysis of a liquid sample in the analysis chamber of the cuvette 1 from the underside of the disk 12, as will be understood by those skilled in the art.

[0055] Referring to FIG. 3, a cross-sectional view of the disk 12 is shown.

[0056] As can be seen in FIG. 3, the receiving openings 14 (with the exception of the analysis openings 47 ) do not penetrate the entire depth of the disc 12 , but only extend partway from the top surface 13 to its opposing bottom surface 23 .

[0057] The majority of the receiving opening 14 is open, in that there is no obstruction between the top surface 26 of the receiving opening 14 and the area immediately above the top surface 13 of the disk 2. However, as noted above, the outer end 17 of the receiving opening 14 includes an overhanging lip 21 that is spaced from the top surface 26 to define a space 24 between the lip 21 and the top surface 26.

[0058] An underside 25 of lip 21 is preferably parallel or substantially parallel to an upper surface 26 of receiving opening 14. When viewed from directly above upper surface 13 of disk 12, an area of ​​upper surface 26 at outer edge 17 of receiving opening 14 is obscured by lip 21.

[0059] The distance between the underside 25 of the lip 21 and the upwardly facing surface 26 of the receiving opening 14 defines a depth that is at least as great as the thickness of the body 2 of the cuvette 1 .

[0060] The length of the receiving opening 14 is preferably sufficient to allow the cuvette 1 to be placed directly into the receiving opening 14 by advancing it into the receiving opening 14 in a direction perpendicular to the plane of the disk 12. Thus, the distance between the inner end 16 of the receiving opening 14 and the free end 27 of the overhanging lip 21 is at least as long as the overall length of the cuvette 1.

[0061] 2, the lip 21 has a first length in a central region of the receiving opening 14 and a second, longer length at the side edges 35, 36 of the receiving opening 14. The free end 39 of the lip 21 preferably describes a curved shape towards the side edges 35, 36 as it transitions from the first length to the second length.

[0062] The use of the cuvette 1 and disk 12 will now be described. As mentioned above, the cuvette 1 is used to collect a sample of a liquid, which in a preferred example may be blood. A subject may use a lancet or other instrument to pierce his / her skin, resulting in the production of a blood drop. The tip 34 of the cuvette 1 may be brought into contact with the blood drop, which causes a volume of blood to be drawn into the receiving chamber of the cuvette 1.

[0063] The cuvette 1 is then placed into the receiving opening 14 of the disk 12 with the tip 4 of the cuvette 1 generally aligned with the inner edge 15 of the receiving opening 14. The underside projections 9 of the cuvette 1 are received in each of the grooves 22 formed as part of the receiving opening 14. In this configuration, each projection 9 is received in (or near) the end of the respective groove 22 closest to the inner edge 15 of the receiving opening 14.

[0064] This situation is shown in Figure 4.

[0065] At this stage, the disk 12 has not yet started to rotate.

[0066] Those skilled in the art will appreciate that the finger holes 20 on either side of the receiving opening 14 increase the ease with which a user can place the cuvette 1 in the receiving opening 14. When a user grips the cuvette 1 to place it in the receiving opening 14, the user is likely to grip the left edge 32 and the right edge 33 of the cuvette 1 between their thumb and index finger. When a user uses this grip to place the cuvette 1 in the receiving opening 14, the presence of the finger holes 20 allows the tips of the user's thumb and index finger to be accommodated within the finger holes 20, thus making it more comfortable and easier to place the cuvette 1 in the receiving opening 14 and reducing the risk of the cuvette 1 dropping into the receiving opening 14 and the associated impact that could damage the cuvette 1 or displace part of the collected blood sample.

[0067] The presence of a groove 22 which receives and cooperates with a projection 9 provided on the underside of the cuvette 1 also makes it possible to unambiguously align the cuvette 1 with respect to the receiving opening 14 .

[0068] If the protrusions 9 are not located within the grooves 22 for any reason, the body 2 of the cuvette 1 will not lie flat against the disk 12, which is easily visible to the user. If the cuvette 1 does not fit properly into the receiving opening 14 for this reason, it is a simple matter for the user to grasp the upright areas of the cuvette 1 and move it until the protrusions 9 are aligned with the grooves 22, at which point the cuvette 1 will drop down so that it is aligned with the plane of the disk 12.

[0069] 4, once the cuvette 1 is placed in the receiving opening 14, centrifugation of the cuvette 1 can begin. The disk 12 rotates about its central axis, and in a preferred embodiment of the present invention, the disk can rotate at, for example, 2000-4000 RPM, for example, 3500 RPM.

[0070] Those skilled in the art will appreciate that as the disk 12 rotates in this manner, a force acts on the cuvette 1 tending to drive the cuvette 1 outwardly relative to the disk 12, i.e., radially away from its central axis toward its outer edge 18. Thus, the cuvette 1 moves radially outwardly relative to the disk 12, and the trailing end 5 of the cuvette 1 moves into the region 24 under the lip 21.

[0071] FIG. 5 shows the position of the cuvette 1 after it has begun to move in this manner, with the rear end 5 of the cuvette within the area 24 under the lip 21, but with a gap 28 between the rear end 5 of the cuvette 1 and the inner end wall 29 of the receiving opening 14.

[0072] As the rotation of the disk 12 continues, the cuvette 1 continues to be driven radially outward. Figure 6 shows the cuvette 1 being driven radially outward as far as possible, at which point the rear end 5 of the cuvette 1 contacts the inner end wall 29. At this point, radial movement of the cuvette 1 relative to the disk 12 stops.

[0073] The presence of the overhanging lip 21 helps to maintain the position of the cuvette 1 during centrifugation. The radial position of the cuvette 1 relative to the disk 12 is fixed and maintained by contact between the rear end 5 of the cuvette 1 and the inner end wall 29. Rapid rotation of the disk 12 results in a relatively high radial force acting on the cuvette 1, tending to engage the cuvette 1 with increasing firmness against the inner end wall 29.

[0074] Furthermore, the fact that the flat rear end 5 of the cuvette 1 is received in the space 24 under the overhanging lip 21 means that the orientation of the cuvette 1 relative to the disk 12 is maintained. The plane of the body 2 of the cuvette 1 is maintained in an orientation parallel or substantially parallel to the plane of the disk 12. Due to the interaction between the rear end 5 of the cuvette 1 and the overhanging lip 21, significant deviations from this alignment are not possible.

[0075] It will also be appreciated that if for any reason a force acts on the cuvette 1 tending to lift the tip 34 of the cuvette 1 out of the receiving opening 14 (and thus rotate the body 2 of the cuvette 1 out of the plane of the disk 12), the presence of the lip 21 will prevent the cuvette 1 from moving significantly in this manner.

[0076] Once the centrifugation process is complete, the rotation of the disk 12 stops. Once the cuvette 1 is removed, it can be grasped by the user and moved towards the inner end 16 of the receiving opening 14. Once this is done, the rear end 5 of the cuvette 1 is no longer within the area 24 under the overhanging lip 21 and the cuvette 1 can be easily removed from the disk 12 by lifting the cuvette 1 directly out of the plane of the disk 12. The finger holes 20 help the user to easily grip the cuvette 1 during this process.

[0077] FIG. 7 shows an enlarged view of the area of ​​outer end 17 of receiving opening 14, in accordance with a preferred embodiment of the present invention.

[0078] As noted above, the disk 12 has an overhanging lip 21 , an area 24 defined below the overhanging lip 21 , and a radially inwardly extending end wall 29 .

[0079] 7, where inward end wall 29 meets underside 31 of overhanging lip 21 there is an inclined surface 30. This inclined surface 30 is preferably set at an angle of about 30° to 60° with respect to the plane of disc 12, more preferably about 45°.

[0080] The rear end 5 of the cuvette 1 is also shown in Figure 7. In the position shown, the rear end 5 is not fully inserted into the space 24 under the overhanging lip 21.

[0081] 7, the depth of the cuvette 1 is less than the depth of the space 24 under the lip 21. However, the depth of the cuvette 1 is about the same as or greater than the depth between the top surface 26 of the receiving opening 14 and the point where the inclined surface 30 meets the inward-facing end wall 29.

[0082] However, the angled surface 30 is not required, and in other embodiments, the angled surface 30 may be absent. In such embodiments, the end wall 29 may meet the underside 25 of the lip 21 and the upper surface 26 of the receiving opening 14 at a right angle.

[0083] Figure 8 shows the centrifugation process at its full extent. As can be seen, the cuvette 1 has been driven radially outward relative to the disk 12, with the trailing end 5 of the cuvette 1 being pushed radially outward as far as possible relative to the disk 12. As this occurs, the trailing end 5 of the cuvette 1 interacts with the inclined surface 30 and is pushed downwards relative to the plane of the disk 12. At this point, further movement of the cuvette 1 relative to the disk 12 is stopped.

[0084] As one skilled in the art will appreciate, the presence of the inclined surface 30 allows the radial position of the cuvette 1 relative to the disk 12 to be maintained and also allows the angular orientation of the cuvette 1 relative to the plane of the disk 12 to be controlled and maintained through contact between the bottom surface 8 of the cuvette 1 and the top surface 26 of the receiving opening 14. One skilled in the art will appreciate that the faster the disk 12 rotates, the greater the radial outward force acting on the cuvette 1 and therefore the more tightly the position and orientation of the cuvette 1 relative to the disk 12 will be maintained.

[0085] Those skilled in the art will appreciate that the distance between the upper surface 26 of the receiving opening 14 and the underside 31 of the overhanging lip 21 must be greater than the depth of the rear end 5 of the cuvette 1, or the cuvette 1 will not fit securely into the space 24 below the lip 21.

[0086] Therefore, if the inclined surface 30 were not present, the rear end 5 of the cuvette 1 could move relative to the disk 12 during centrifugation, particularly since the centrifugation process could cause vibration of the disk 12.

[0087] However, the presence of the inclined surface 30 means that the position and angular orientation of the cuvette 1 relative to the disk 12 is firmly maintained, thus increasing the ease and reliability with which a liquid sample in the cuvette can be analysed.

[0088] In an embodiment of the invention, the rear end 5 of the cuvette 1 may include a beveled surface (not shown) having an angle that matches or substantially matches the angle of the beveled surface 30 formed as part of the disk.

[0089] In a preferred embodiment of the present invention, the cuvette 1 is symmetrical or substantially symmetrical with respect to the plane of the body 2, and therefore an inclined surface can be formed whether or not both the top surface 7 and the bottom surface 8 intersect with the rear end surface 37 of the cuvette 1.

[0090] In the example described above, the lip 21 extends from the end wall 29 of the receiving opening 14. However, in other embodiments, there may be a space 38 between the end wall 29 and the lip 21, as shown in Figure 9. As one skilled in the art will appreciate, the lip 21 is supported on either side of the receiving opening 14, in this example, via a connection to (or integrally formed with) a region of the disk 12.

[0091] In one example, the overall length of the cuvette 1 is 78.9 mm, and the length of the lip 21 is 3.46 mm at the center of the receiving opening and 7.23 mm at the side edges 35, 36. In general, the lip 21 is preferably long enough so that the rear end 5 of the cuvette 1 is fully received in the space 24 below the lip 21, and if the cuvette 1 rotates to lift its front end 3 upward from the receiving opening 14, the movement of the center of gravity of the cuvette 1 cannot move upward more than half the thickness of the cuvette 1. In the present example, this corresponds to a maximum rotation angle of the cuvette of 3.81°. On this basis, the minimum length of the lip 21 is about 5.4 mm (if the lip 21 has a length that varies across its width, as shown for example in FIG. 2, this applies to the longest portion of the lip 21).

[0092] The lip is effective in holding the cuvette 1 in place, but may be so long that it requires the disk 12 to be overly large to accommodate the cuvette, or so long that it is inconvenient for a user to remove the cuvette 1 from the lip 21 after a centrifugation operation, but it is preferred that the lip not have a length much longer than this.

[0093] In a preferred embodiment, the cuvette is 4.95 mm deep and the receiving opening is approximately 5.34 mm deep.

[0094] In a preferred embodiment, the length of the lip is at least 5% of the length of the receiving opening. The length of the lip may preferably be at least 7% of the length of the receiving opening. In a further embodiment, the length of the lip may be at least 10% of the length of the receiving opening.

[0095] In absolute terms, in preferred embodiments, the lip length may be at least 3 mm. More preferably, the lip length may be at least 5 mm. Even more preferably, the lip length may be at least 7 mm.

[0096] Where the length of lip 21 varies across its width (as in the example shown in FIG. 2), the lengths mentioned above preferably refer to the longest portion(s) of lip 21. In this example, the longest portion is the portion closest to the side edges 35, 26 of the receiving opening.

[0097] In the illustrated example, the lip 21 is provided at or near the end wall 29 at the end of the receiving opening 14 furthest from the axis of rotation of the disk 12. However, this need not be the case.

[0098] Referring to Figure 10, there is shown a further example of a cuvette 40 embodying the present invention. The further cuvette 40 is similar to the cuvette 1 shown in Figure 1, except that the further cuvette 40 has a pair of retaining arms 41 projecting from respective side edges 32, 33 thereof. Each retaining arm 41 has a straight or substantially straight edge 42 on a side facing generally away from the tip 34 of the cuvette 40, and is perpendicular or substantially perpendicular to the longitudinal axis of the cuvette 40.

[0099] In the illustrated example, the holding arms 41 are disposed approximately symmetrically on both sides of the cuvette 40 .

[0100] 11 shows a further receiving opening 43 suitable for use with a further cuvette 40. The further receiving opening 43 is similar to the retaining opening 14 described above, with the following differences.

[0101] The further receiving opening 43 does not have an overhanging lip at its outer end 17 .

[0102] The further receiving opening 43 has a pair of receiving areas 44 projecting outwardly from its side edges 35, 36. Each receiving area 44 is dimensioned to receive one of the retaining arms 41.

[0103] Each receiving area 44 has an end wall 45 that generally faces the axis of rotation of the disk 12 and is perpendicular or substantially perpendicular to the longitudinal axis of the cuvette 40. An overhanging lip 46 is provided in the region of each end wall 45 and is spaced apart from the upwardly facing surface 26 of the receiving opening 43 to define a space between the underside of the lip 46 and the upwardly facing surface 26 of the receiving opening 43. Those skilled in the art will appreciate that the lip 46 of each receiving area 44 is similar to the lip 21 of the example shown in Figures 2-9.

[0104] In use, the further cuvette 40 is placed in the further receiving opening 43 such that each retaining arm 41 is located in one of the receiving areas 44. When the disk 12 is subsequently centrifuged, the cuvette 40 is driven radially outwardly relative to the disk 12, with the straight edge 42 of each retaining arm 41 moving into the area under the lip 46 of the respective receiving area 44.

[0105] This situation is illustrated in Figure 12. The edges 42 of the retaining arms 41 are shown in Figure 12 for clarity, but it should be understood that these edges 42 are hidden behind the lips 46 of the respective receiving areas 44.

[0106] Those skilled in the art will appreciate that, for reasons similar to those discussed above with respect to the embodiment shown in Figures 1-9, the interaction between the overhanging lip 46 and the retaining arm 41 holds the cuvette 40 securely in place relative to the receiving opening 43 during the centrifugation process.

[0107] A ramp similar to that described above with respect to the embodiment shown in FIGS. 7 and 8 may be provided in the space beneath each of the lips 46. As shown in FIG.

[0108] In the embodiment of Figures 10-12, the cuvette 40 is held in place relative to the receiving opening 43 at two separate locations, and also at a location closer to the center of the cuvette 40 (in the direction from the tip 34 to the rear end 5 of the cuvette 40), so that the cuvette 40 can be held in place with greater reliability.

[0109] In yet a further embodiment (not shown), the receiving opening may have a receiving area 44 as shown in Figures 11 and 12, and an overhanging lip 21 at its outer end 17 as shown in Figures 2-9. Those skilled in the art will appreciate that this combination of features will hold the cuvette in place more reliably.

[0110] In conventional centrifuges utilizing a rotating component such as a disk, the disk has an opening in which a sample holder such as a cuvette is received so as to lie generally in the plane of the disk, and it is conventional to have a lid or cover that is placed over the disk during the centrifugation process. The cover may be hinged to the body of the centrifuge, or may be completely removable. In use, a user lifts the cover upward to expose all or a portion of the disk, inserts one or more sample holders into the corresponding openings in the disk, and then closes and secures the cover before the disk begins to spin. The centrifuge may have a safety interlock system that prevents the disk from being driven into rotation if the cover is not properly closed.

[0111] In embodiments of the present invention, the centrifuge may not have a lid or cover covering the top side of the disk 12. In use, when the disk 12 is driven to rotate as part of the centrifugation process, at least a portion of the disk 12 is exposed and may be accessed. In particular, when the disk 12 is stationary, the receiving opening 14 may be exposed, allowing a user to place a cuvette 1, 40 into the receiving opening 14 without a further lid or cover being moved into place to cover the disk 12 before the centrifugation process begins. In some embodiments, all or substantially all of the top surface 13 of the disk 12 is exposed during the centrifugation process.

[0112] This is possible because the cuvette 1, 40 is held securely in place during the centrifugation process by the presence of one or more lips 21, 46. In contrast, in conventional systems where the sample holder is placed in an opening in the top surface of the disk, the opening has no associated lip and the cuvette is very likely to fly out of the opening during the centrifugation operation, posing a serious hazard to the user.

[0113] The lack of a lid or cover makes the centrifuge of the present invention simpler and easier to use, especially for those with reduced or impaired vision and / or dexterity. The lack of a lid or cover also reduces the weight and cost of the centrifuge.

[0114] However, in other embodiments, the centrifuge may have a lid or cover that covers the top side of the disk 12 during centrifugation.

[0115] Those skilled in the art will appreciate that embodiments of the present invention provide a system for collecting and analyzing liquid samples that may be easily used by non-professionals and those without significant training in the use of the system, particularly users who may have impaired dexterity and / or vision. This is particularly important for use of the present invention to monitor the health of a subject at home, where the subject may be elderly and / or suffer from one or more diseases or conditions.

[0116] As used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. These terms are not to be interpreted as excluding the presence of other features, steps or components.

[0117] The invention may also broadly reside in any and all combinations of two or more of the moieties, elements, steps, examples and / or features referred to or indicated herein, individually or collectively. In particular, one or more features in any of the embodiments described herein may be combined with one or more features from any other embodiment(s) described herein.

[0118] Protection may be sought for any features disclosed in any one or more of the publications referenced herein in combination with this disclosure.

[0119] Although specific exemplary embodiments of the present invention have been described, the appended claims are not intended to be limited to only those embodiments, and the claims should be construed literally, intentionally, and / or to encompass equivalents.

Claims

1. A centrifuge comprising a rotor that can be driven to rotate during a centrifugal separation process, wherein the rotor has a rotating shaft and an outer edge, The rotor has an opening for receiving a sample holder, the opening is formed on a first surface of the rotor and is located between the rotation axis and the outer edge, and the opening has an inner surface into which the sample holder can be received. The opening generally has an end wall facing toward the axis of rotation, A centrifugal separator wherein the rotor includes a lip that overlaps a portion of the opening in the region of the end wall, the lip being spaced apart from the inner surface and defining a region between the inner surface and the lower side of the lip.

2. The centrifugal separator according to claim 1, wherein the opening has an inner end closest to the rotation axis and an outer end closest to the outer edge, and the lip overlaps a part of the opening at or near the outer end.

3. The centrifuge according to claim 1, wherein the rotor has a first surface on which the opening is formed, and the inner surface is offset from the first surface of the rotor.

4. The centrifugal separator according to claim 3, wherein in the region of the lip, the lip is parallel or substantially parallel to the first surface of the rotor.

5. The centrifugal separator according to claim 3, wherein in the region of the lip, the upper surface of the lip is aligned with or substantially aligned with the first surface of the rotor.

6. The centrifuge according to claim 3, wherein the opening does not penetrate the entire thickness of the rotor.

7. The centrifuge according to claim 6, wherein the first surface of the rotor is its upper surface.

8. The centrifugal separator according to claim 7, wherein the rotor has a lower surface, and the thickness of the rotor is defined between the upper surface and the lower surface.

9. The centrifuge according to claim 1, wherein the lip is adjacent to the end wall.

10. A deflection surface is formed between the end wall and the lower side of the lip, and the deflection surface is at an angle with respect to both the end wall and the lower side of the lip, according to claim 1.

11. A centrifugal separator according to claim 1, wherein a deflection surface is formed extending between the end wall and the inner surface, and the deflection surface forms an angle with respect to both the end wall and the inner surface.

12. The centrifugal separator according to claim 1, wherein in the region of the lip, the opening has a width, and the lip extends completely or substantially completely over the entire width.

13. The centrifugal separator according to claim 1, wherein the length of the lip is at least 5% of the length of the opening.

14. The centrifugal separator according to claim 1, further comprising a housing to which the rotor is attached, and a drive mechanism for driving the rotational motion of the rotor.

15. The centrifuge according to claim 1, wherein the centrifuge does not have a cover that is positioned directly above the opening during the centrifugal separation process.

16. A centrifugal separator according to claim 1, A centrifugal separator comprising a cuvette, the cuvette being capable of receiving a cuvette within the opening.

17. The centrifugal separator according to claim 16, wherein the cuvette may be positioned in an initial location within the opening by being advanced into the opening in a direction substantially perpendicular to the rotation axis of the rotor, and as a result the cuvette is received in a region of the opening other than the region between the inner surface and the lower side of the lip.

18. From the initial position, the cuvette can be moved to a second position in which a portion of the cuvette is received in the region between the inner surface and the lower side of the lip, in a direction passing from the rotation axis of the rotor toward the outer edge of the rotor, without being removed from the opening.

19. The centrifugal separator according to claim 18, wherein when the cuvette is in the initial position, rotation of the rotor around the rotation axis at a sufficient speed drives the cuvette to the second position.

20. The centrifugal separator according to claim 18, wherein the opening includes one or more finger holes that include a region of the opening that is not occupied by the cuvette when the cuvette is received in the opening.

21. The centrifugal separator according to claim 20, wherein the finger hole comprises a region of the opening that is not occupied by the cuvette in either the initial position or the second position.

22. The centrifugal separator according to claim 20, wherein the opening comprises two finger holes, the finger holes extending from substantially opposite the opening.

23. The centrifugal separator according to claim 20, wherein the finger holes or each of the finger holes extend from the opening in a direction substantially perpendicular to the direction passing from the rotation axis of the rotor to the outer edge of the rotor.

24. The centrifugal separator according to claim 18, wherein the cuvette has one or more protruding ridges, the inner surface of the rotor has one or more corresponding grooves formed therein, and when the cuvette is positioned in the first or second position, the one or more grooves are received in each groove.

25. The centrifugal separator according to claim 24, wherein the cuvette can slide against the inner surface from a first position to a second position, and one or more grooves remain within each of the grooves.

Images