Radial locking system for attaching rotor

Abstract

A driver head (20) of a centrifuge driver is used to detachably connect a rotor to a centrifuge. The driver head includes a driver head hub (74) having a plurality of recesses (98) spaced circumferentially and symmetrically about the driver head hub, a locking slider (80) movably retained within each of the plurality of recesses and radially movable therein, and a resilient element (102) disposed between the plurality of recesses (98) and the locking slider (80). A resilient element is located between each locking slider and the driver head hub for biasing each locking slider in a radially outward direction relative to the axis of rotation of the centrifuge driver. Each locking slider is configured to exert a radially outwardly directed force on an inner sidewall of a hub of the centrifuge rotor to prevent axial movement of the centrifuge rotor along a rotational axis of the centrifuge driver and rotational movement of the centrifuge rotor relative to the driver head, wherein the radially outwardly directed force increases as the rotational speed of the drive head increases.

Description

Technical Field

[0001] The present invention relates generally to centrifuges and, more particularly, to a drive head locking system for removably connecting a rotor to a centrifuge drive of a centrifuge. Background Art

[0002] Laboratory centrifuges typically include a rotor that is removably coupled to a drive that is used to spin the rotor at a specific speed required to centrifuge a sample stored in the rotor. Although centrifuge rotors can vary widely in structure and size, a common rotor configuration is a fixed angle rotor and a swing bucket rotor (also known as a swing-out rotor), each of which has a solid rotor body with a plurality of receiving chambers or rotor wells radially distributed within the rotor body and symmetrically arranged around the axis of rotation of the rotor. Samples in appropriately sized sample containers are placed in the plurality of rotor wells, allowing multiple samples to be centrifuged as the rotor is rotated by the centrifuge drive.

[0003] In order to rotate the rotor at a specific speed, the rotor is removably attached to the drive shaft or spindle driven by the motor of the centrifuge. In this regard, the centrifuge spindle generally includes a locking system, which is configured to be received by the rotor, for the rotor to be fixedly connected to the centrifuge driver and to transmit torque between the driver and the rotor so that the rotor rotates at a specific speed. A type of conventional locking system is a locking system operated by centrifugal force. In other words, as the rotating speed of the rotor increases, the coupling force applied to the rotor by the coupling device increases. However, the locking systems of these conventional types generally require the use of tools to initially connect the rotor and the centrifuge driver and to separate the rotor from the centrifuge driver. Other conventional locking system designs include integrated actuators or buttons, which are operable to, for example, initially connect the rotor and the centrifuge driver and to separate the rotor from the centrifuge driver. The use of tools or other mechanisms to mechanically couple the rotor to the centrifuge drive for this purpose is a result of the limited performance capabilities of centrifugally operated locking systems, which are limited by their ability to withstand the associated axial forces and torques caused by centrifugal forces during rotation of the centrifuge rotor by the centrifuge drive, particularly at high rotational speeds.

[0004] Therefore, there is a need to provide a centrifuge which ensures reliable locking against both rotational forces and axial lifting forces acting on the centrifuge rotor during a range of rotational speeds, but in particular at high rotational speeds, wherein the locking force increases with increasing rotational speed of the centrifuge rotor. Furthermore, the rotor should be mountable to and dismountable from the centrifuge drive in a very short time and, for example, without the use of tools, buttons or other mechanical actuators. Summary of the invention

[0005] The present invention overcomes the aforementioned and other disadvantages and drawbacks of centrifuge drive head locking systems for removably connecting a rotor to a centrifuge drive.Although the present invention will be discussed in conjunction with certain embodiments, it should be understood that the invention is not limited to the specific embodiments described herein.

[0006] According to one embodiment of the present invention, a driver head for a centrifuge driver is provided. The driver head is configured to be received in the hub of a centrifuge rotor for coupling the centrifuge rotor to the centrifuge driver so that the centrifuge rotor rotates around the rotation axis of the centrifuge driver through the centrifuge driver. The hub of the centrifuge rotor includes at least one drive pin for transmitting the rotational motion of the centrifuge driver to the centrifuge rotor. The driver head includes a driver head hub, which includes a central hole configured to receive a fastener passing therethrough to couple the driver head to the spindle of the centrifuge driver. The driver head hub includes: a plurality of recesses formed in the outer side wall of the driver head hub and circumferentially and symmetrically spaced about the driver head hub; a locking slider that is movably retained in each of the plurality of recesses and can be moved therein in a radially inward direction and a radially outward direction relative to the rotation axis of the centrifuge driver; and an elastic element located between each locking slider and the driver head hub for biasing each locking slider in a radially outward direction relative to the rotation axis of the centrifuge driver. Each locking slider is configured to exert a radially outwardly directed force on the inner side wall of the hub of the centrifuge rotor to prevent axial movement of the centrifuge rotor along the rotation axis of the centrifuge drive and rotational movement of the centrifuge rotor relative to the drive head, wherein the radially outwardly directed force increases with increasing rotational speed of the drive head.

[0007] According to one aspect of the invention, the driver head includes a crown attached to the top of the driver head hub. The crown includes a center hole and a plurality of torque grooves formed in the top surface of the crown, the center hole being configured to receive a fastener passing therethrough, the plurality of torque grooves being configured to receive at least one drive pin of the hub of the centrifuge rotor to transmit the rotational motion of the centrifuge driver to the centrifuge rotor. The driver head also includes a retaining plate attached to the base of the driver head hub. The retaining plate includes a center hole configured to receive the distal end of the spindle passing therethrough.

[0008] According to another aspect of the invention, each locking slide comprises a curved outer surface in cross section that matches the curvature of the inner side wall of the hub of the centrifuge rotor in cross section. According to one aspect, each locking slide comprises a chamfered surface extending between the curved outer surface and the top surface of each locking slide to facilitate insertion of the drive head into the hub of the centrifuge rotor.

[0009] According to another aspect of the present invention, each locking slider is movable between a first position and a second position, in which the first position, each locking slider is received in a corresponding one of the plurality of recesses in a radially inward direction relative to the rotation axis of the centrifuge drive to define a first outer diameter of the drive head hub, and in which the second position, each locking slider protrudes a certain distance from a corresponding one of the plurality of recesses in a radially outward direction relative to the rotation axis of the centrifuge drive to define a second outer diameter of the drive head hub, which is greater than the first outer diameter.

[0010] According to one aspect of the invention, a plurality of recesses are equally spaced around the circumference of the driver head hub to provide self-centering of the driver head within the centrifuge rotor hub by each locking slider. According to another aspect, each locking slider is capable of slidably engaging a base surface of the crown and a top surface of the retaining plate. According to yet another aspect, each locking slider includes a pair of shoulders configured to engage with an abutment surface of each recess to prevent the locking slider from over-extending from each recess by a resilient element.

[0011] According to one aspect, the driver head hub includes a boss protruding upward from the top surface of the driver head hub, the boss being configured to be received in a recess formed in the base of the crown for coupling the driver head hub to the crown. According to another aspect, the fit between the boss of the driver head hub and the recess of the crown is an interference fit.

[0012] According to yet another aspect of the invention, each torque slot is an arcuate blind hole. According to another aspect, a plurality of torque slots are circumferentially spaced around the central hole of the crown. According to one aspect, a first drive pin of the hub of the centrifuge rotor is configured to engage the side wall of the first torque slot to prevent rotation of the drive head relative to the centrifuge rotor during acceleration of the centrifuge rotor by the centrifuge drive. According to another aspect, a second drive pin of the hub of the centrifuge rotor is configured to engage the side wall of the second torque slot to prevent rotation of the drive head relative to the centrifuge rotor during deceleration of the centrifuge rotor by the centrifuge drive.

[0013] According to one aspect of the invention, a centrifuge is provided with a drive head and includes a centrifuge rotor having a hub configured to receive the drive head therein, the hub including at least one drive pin protruding from an inner surface of the hub in an axially downward direction relative to an axis of rotation of the centrifuge drive, the at least one drive pin being configured to transmit the rotational motion of the centrifuge drive to the centrifuge rotor.

[0014] According to another embodiment of the present invention, a driver head for a centrifuge driver is provided. The driver head is configured to be received in the hub of a centrifuge rotor for coupling the centrifuge rotor to the centrifuge driver so that the centrifuge rotor rotates around the axis of rotation of the centrifuge driver by the centrifuge driver. The hub of the centrifuge rotor includes at least one torque groove formed therein. The driver head includes a driver head hub, the driver head hub including a center hole, the center hole being configured to receive a fastener passing therethrough to couple the driver head to the spindle of the centrifuge driver. The drive head hub includes: a plurality of recesses formed in an outer side wall of the drive head hub and spaced circumferentially and symmetrically about the drive head hub; a locking slider movably retained within each of the plurality of recesses and movable therein in a radially inward direction and a radially outward direction relative to the rotational axis of the centrifuge drive; a resilient element located between each locking slider and the drive head hub for biasing each locking slider in a radially outward direction relative to the rotational axis of the centrifuge drive; and a crown attached to a top of the drive head hub, the crown including a central hole and at least one drive pin, the central hole being configured to receive a fastener therethrough, and the at least one drive pin being configured to engage at least one torque groove formed in the hub of the centrifuge rotor to transmit the rotational motion of the centrifuge drive to the centrifuge rotor. Each locking slider is configured to exert a radially outwardly directed force on the inner side wall of the hub of the centrifuge rotor to prevent axial movement of the centrifuge rotor along the rotation axis of the centrifuge drive and rotational movement of the centrifuge rotor relative to the drive head, wherein the radially outwardly directed force increases with increasing rotational speed of the drive head.

[0015] According to one aspect of the invention, a driver head includes a retention plate attached to a base of a driver head hub, the retention plate including a central aperture configured to receive a distal end of a spindle therethrough.

[0016] According to another aspect of the invention, each locking slider includes a curved outer surface in cross section that matches the curvature of the inner side wall of the hub of the centrifuge rotor in cross section. According to yet another aspect, each locking slider includes a chamfered surface that extends between the curved outer surface and the top surface of each locking slider to facilitate insertion of the drive head into the hub of the centrifuge rotor. According to yet another aspect, each locking slider is movable between a first position and a second position, in which each locking slider is received in a corresponding one of a plurality of recesses in a radially inward direction relative to the rotation axis of the centrifuge drive to define a first outer diameter of the drive head hub, and in which each locking slider protrudes a distance from a corresponding one of a plurality of recesses in a radially outward direction relative to the rotation axis of the centrifuge drive to define a second outer diameter of the drive head hub, the second outer diameter being greater than the first outer diameter.

[0017] According to one aspect, a plurality of recesses are equally spaced around the circumference of the drive head hub to provide self-centering of the drive head within the hub of the centrifuge rotor through each locking slider. According to another aspect, each locking slider is capable of slidably engaging the base surface of the crown and the top surface of the retaining plate. According to yet another aspect, each locking slider includes a pair of shoulders configured to engage with an abutting surface of a corresponding one of the plurality of recesses to prevent over-extension of the locking slider with the corresponding one of the plurality of recesses. According to one aspect, at least one drive pin includes a first drive pin, a second drive pin, and a third drive pin spaced circumferentially around the center hole of the crown.

[0018] According to another aspect of the present invention, a centrifuge including a driver head is provided. The centrifuge includes a centrifuge rotor having a hub configured to receive the driver head therein. The hub includes at least one torque slot formed therein, the at least one torque slot being configured to receive at least one drive pin of the crown for transmitting the rotational motion of the centrifuge driver to the centrifuge rotor. According to one aspect, each torque slot is an arc-shaped blind hole. According to another aspect, the at least one torque slot includes four torque slots spaced circumferentially around a center hole formed in the hub.

[0019] According to yet another aspect of the invention, the first drive pin of the crown is configured to engage the sidewall of the first torque slot to prevent rotation of the drive head relative to the centrifuge rotor during acceleration of the centrifuge rotor by the centrifuge drive. According to one aspect, the second drive pin of the crown of the centrifuge rotor is configured to engage the sidewall of the second torque slot to prevent rotation of the drive head relative to the centrifuge rotor during deceleration of the centrifuge rotor by the centrifuge drive.

[0020] According to another embodiment of the present invention, an adapter for mounting a driver head to a spindle of a centrifuge driver is provided. The driver head is configured to be received in the hub of a centrifuge rotor for coupling the centrifuge rotor to the centrifuge driver so that the centrifuge rotor rotates around the axis of rotation of the centrifuge driver by the centrifuge driver. The driver head includes a central hole configured to receive a fastener therethrough to couple the driver head to the distal end of the spindle of the centrifuge driver. The adapter includes: a first protrusion configured to be received in a recess formed in the driver head; a second protrusion protruding in an axially opposite direction to the first protrusion; and a mounting hole extending axially through the adapter and extending between a first opening leading to the mounting hole formed in the first protrusion of the adapter and a second opening leading to the mounting hole formed in the second protrusion of the adapter. The mounting hole is configured to receive the distal end of the spindle through the second opening so that the central hole of the drive head, the mounting hole and the threaded hole in the distal end of the spindle are coaxially arranged to receive a fastener therethrough to couple the drive head and the adapter to the distal end of the spindle of the centrifuge drive.

[0021] According to one aspect of the invention, the adapter comprises a cup-shaped flange axially located between the first and second projections. According to another aspect, the first projection is frustoconical in shape. According to yet another aspect, the mounting hole is frustoconical in shape.

[0022] Various additional features and advantages of the present invention will become more apparent to those of ordinary skill in the art upon reading the following detailed description of one or more illustrative embodiments in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate one or more embodiments of the present invention and, together with the general description given above and the detailed description given below, serve to explain one or more embodiments of the present invention.

[0024] Figure 1 is a cross-sectional view of a centrifuge according to a first embodiment of the present invention showing a centrifuge rotor coupled to a drive head of a centrifuge drive.

[0025] Figure 2 yes Figure 1 An enlarged partial cross-sectional view of a centrifuge showing a drive head received within a hub of a centrifuge rotor.

[0026] Figure 2A yes Figure 1-Figure 2Magnified view of a centrifuge showing the engagement between the annular lip of the hub of the centrifuge rotor and the surface of the locking slide.

[0027] Figure 3 is similar to Figure 2 sectional view showing a centrifuge rotor coupled to a drive head.

[0028] Figure 3A yes Figure 1-Figure 3 Magnified view of a centrifuge showing the engagement between the base of the locking slide and the annular lip of the hub of the centrifuge rotor.

[0029] Figure 4 is along Figure 3 The cross-sectional view taken along line 4-4 in Figure 1 shows the forces acting on the locking slide of the drive head when the drive head is stationary.

[0030] Figure 5 is similar to Figure 4 , showing the forces acting on the locking slide of the drive head when the drive head rotates a centrifuge rotor at a specific speed.

[0031] Figure 6 is along Figure 3 The cross-sectional view taken along line 6-6 in FIG. 1 shows the position of the drive pin relative to the corresponding torque slot in the drive head when the drive head rotates the centrifuge rotor in a counterclockwise direction at a particular speed.

[0032] Figure 7 is similar to Figure 6 , showing the position of the drive pin relative to the corresponding torque slot in the driver head as the driver head decelerates to a stop.

[0033] Figure 8 yes Figure 1-Figure 8 Exploded view of the drive head.

[0034] Fig. 9 is a cross-sectional view of a centrifuge according to a second embodiment of the present invention showing a centrifuge rotor coupled to a drive head of a centrifuge drive.

[0035] Fig.10 yes Fig. 9 An enlarged cross-sectional view of a centrifuge showing a drive head housed within the hub of a centrifuge rotor.

[0036] Fig.11 It is along Fig.10 The cross-sectional view taken along line 11-11 in FIG. 1 shows the position of the drive pin relative to the corresponding torque groove in the hub of the centrifuge rotor when the drive head rotates the centrifuge rotor in a counterclockwise direction at a particular speed.

[0037] Fig.12 is similar to Fig.11 , showing the position of the drive pin relative to the corresponding torque slot in the hub of the centrifuge rotor as the drive head slows to a stop.

[0038] Fig.13 is a cross-sectional view of a drive head attached to a spindle of a centrifuge with an adapter according to an embodiment of the present invention.

[0039] Fig.14 is a schematic diagram showing a centrifuge rotor installed in an exemplary centrifuge. DETAILED DESCRIPTION

[0040] Referring now to the drawings, and in particular to Figure 1 , shows an exemplary centrifuge 10 according to a first embodiment of the present invention, which does not have any substructures of the centrifuge 10. Figure 1 As shown, the centrifuge 10 includes a centrifuge rotor 12, which is operably connected to a centrifuge drive 14, which has a drive shaft or spindle 16 driven by a motor 18, for rotating the rotor 12 around an axis of rotation A1 to achieve high-speed, centrifugal rotation of the rotor 12. As shown, the centrifuge drive 14 includes a drive head 20 positioned at one end of the spindle 16, which is configured to be received in a hub 22 of the rotor 12, for removably connecting the rotor 12 to the centrifuge drive 14 in a tool-free manner, as will be described in further detail below. The connection between the drive head 20 and the rotor 12 not only axially fixes the rotor 12 to the centrifuge drive 14, but also facilitates the transmission of torque between the centrifuge drive 14 and the rotor 12, so that the rotor 12 rotates with the rotation required for the centrifugal sample contained therein. The connection also provides self-centering of the drive head 20 in the hub 22 of the rotor 12, as will be described in further detail below.

[0041] Continue to refer Figure 1, an exemplary centrifuge rotor 12 includes a rotor body 24 and a rotor cover 26, which is configured to be coupled to an open end of the rotor body 24, particularly, for example, during centrifugation of a sample. In this regard, the rotor body 24 is symmetrical about a common rotation axis A1 with the centrifuge drive 14. The rotor 12 includes a plurality of rotor wells 28 (also referred to as receiving chambers or cell well cavities) formed in the rotor body 24 and radially distributed around a vertical hole 30 formed through the axial center of the rotor 12 in a symmetrical arrangement. Each rotor well 28 formed in the rotor body 24 is substantially cylindrical in shape and is configured to receive a sample container (not shown) therein to centrifuge a sample held in the sample container. Each rotor well 28 can be formed in the rotor body 24 so as to have a fixed angular relationship relative to the rotation axis A1 of the rotor 12. For this purpose, the rotor 12 can be considered a high-speed, fixed-angle rotor 12, for example, which is designed to rotate at a speed ranging from about 8,000 rpm to about 30,000 rpm.

[0042] However, while the rotor 12 is shown and described in the context of a fixed angle rotor having certain characteristics, it should be understood that the same inventive concepts associated with embodiments of the present invention may be implemented with different types of centrifuge rotors, such as swing bucket rotors and vertical rotors, for example, without departing from the scope of the present invention. For example, the inventive concepts associated with embodiments of the present invention may be implemented using the following rotors (listed by model) commercially available from the assignee of the present disclosure: Fiberlite TM F10-6x250 LEX、Fiberlite TM F10-6x100 LEX、Fiberlite TM F15-6x100y, Fiberlite TM F15-8x50cy, Fiberlite TM F15-48x1.5 / 2.0, Fiberlite TM F10-14x50cy, H3-LV, Fiberlite TM F15-24x1.5 / 2.0、BIOShield TM -720, TX-100, TX-150, TX-200, TX-400, TX-750, HIGHTPlate TM -6000. For this purpose, the drawings are not intended to be limiting.

[0043] Continue to refer Figure 1, the rotor 12 includes a rotor insert 32 disposed within a central interior region of the rotor body 24, the rotor insert being configured to threadedly engage with the rotor hub 22. As shown, the rotor insert 32 is positioned about the rotation axis A1 and is configured to receive and threadedly engage the rotor hub 22 to hold the rotor hub 22 in position within the vertical bore 30 of the rotor 12. The engagement between the rotor insert 32 and the rotor hub 22 exposes an externally threaded top portion 34 of the hub 22 from the vertical bore 30, to which a hub retainer 36 is threadedly fastened to hold the hub 22 in position relative to the rotor body 24.

[0044] The rotor 12 also includes a cap screw 38 for securing the rotor cover 26 to the rotor body 24. The cap screw 38 is configured to be screwed into the internally threaded top portion 40 of the rotor hub 22, so that turning the cap screw 38 to engage the hub 22 presses the cap screw 38 down on the cover 26, thereby securing the cover 26 to the rotor 12. As shown, the cap screw 38, the hub 22, and the rotor insert 32 are coaxially arranged with the vertical hole 30 formed in the rotor body 24. The cover 26 seals and closes the open end of the rotor body 24 to prevent access to one or more sample containers held in the rotor well 28 during high-speed rotation of the rotor 12.

[0045] Now refer to Figure 1-Figure 3 , the hub 22 of the rotor 12 includes an internal cavity 46 that is configured to receive the drive head 20 of the centrifuge drive 14 therein for coupling the rotor 12 to the centrifuge drive 14. In this regard, the shape of the cavity 46 generally corresponds to the profile of the drive head 20. More specifically, the internal cavity 46 extends from the open end 48 of the hub 22 to the radially extending base surface 50 of the hub 22 to define a crown receiving portion 52 and a drive head hub receiving portion 54 of the cavity 46. The crown receiving portion 52 is defined by an inclined sidewall 56 and a first tubular sidewall 58 that extends in an axial direction between the base surface 50 and the inclined sidewall 56. The drive head hub receiving portion 54 is defined by a second tubular sidewall 60 that extends in an axial direction from the open end 48 of the hub 22 to the inclined sidewall 56. The second tubular sidewall 60 also includes an annular lip 62 that is configured to engage the driver head 20 during installation and removal of the rotor 12 therefrom, as described in further detail below.

[0046] The base surface 50 of the hub 22 includes a plurality of blind holes 64, each of which is configured to receive a corresponding drive pin 66 therein. The drive pins 66 are configured to engage the drive head 20 to transfer the rotational motion of the centrifuge drive 14 to the rotor 12, as described in further detail below. Figure 1-Figure 3As shown, each blind hole 64 is configured to receive a corresponding drive pin 66 therein, and in the illustrated embodiment, the hub 22 includes a combination of two blind holes 64 and drive pins 66. The combination of blind holes 64 and drive pins 66 are spaced 180° apart from each other about the axial center of the hub 22 coaxial with the rotation axis A1 (e.g., Figure 6 and Figure 7 ). However, the hub 22 may include fewer or more blind holes 64 and drive pin 66 combinations spaced apart in different configurations around the axial center of the hub 22. For example, the hub 22 may include three blind holes 64 and drive pin 66 combinations spaced 120° from each other around the axial center of the hub 22. In any case, the engagement between each drive pin 66 and the blind hole 64 is an interference fit, also known as a press fit. As a result, there may be a gap between the base of each blind hole 64 and the drive pin 66. However, it should be understood that the drive pin 66 can be attached to the hub 22 in other ways, such as by welding or by threaded engagement. In one embodiment, the hub 22 and the drive pin 66 can be integrally formed as a single piece.

[0047] Continue to refer Figure 1-Figure 3 , the details of the drive head 20 will now be described. As shown, the drive head 20 is permanently mounted to the distal end 70 of the spindle 16 using fasteners 72, and includes a drive head hub 74, a crown 76, and a retaining plate 78 coupled together in a coaxial arrangement. The drive head hub 74 includes a plurality of radially movable locking slides 80 that are configured to apply a radially outwardly directed force on the hub 22 of the rotor 12 that increases as the rotational speed of the drive head 20 increases. In this regard, the locking slides 80 are used to prevent axial movement of the centrifuge rotor 12 along the rotational axis A1 of the centrifuge drive 14 and rotational movement of the centrifuge rotor 12 relative to the drive head 20, and also provide self-centering of the drive head 20 within the hub 22 of the rotor 12, as described in further detail below. As Figure 3 As best shown in FIG. 1 , the crown 76 and the driver head hub 74 each include a central hole 82, 84, respectively, which is configured to receive the fastener 72 therethrough for attaching the driver head 20 to the distal end 70 of the spindle 16. The retaining plate 78 includes a central hole 86 that is configured to receive the distal end 70 of the spindle 16 therethrough. To this end, the fastener 72, which may be a bolt or screw, for example, is received through the aligned holes 82, 84 and threaded into a threaded hole 88 in the distal end 70 of the spindle 16.

[0048] Reference Figure 1-Figure 3 and Figure 8The driver head hub 74 includes a generally cylindrical boss 90 protruding upward from a top surface 92 of the driver head hub 74 and a recess 94 formed in a base 96 of the driver head hub 74. The recess 94 extends a distance from the base 96 into the driver head hub 74 in an axial direction and is configured to receive a portion of the distal end 70 of the spindle 16 therein, as shown. The structure of the recess 94 achieves the same effect as a locking cone or Morse taper, thereby causing a self-retaining frictional engagement between the surface of the recess 94 and the surface of the spindle 16. A central hole 84 formed in the driver head hub 74 extends between the boss 90 and the recess 94 in an axial direction and is configured to receive a fastener 72 therethrough. The driver head hub 74 also includes a plurality of recesses 98 formed in an outer side wall 100 of the driver head hub 74, each recess 98 being configured to movably retain a corresponding locking slide 80 therein.

[0049] like Figure 4 As shown, for example, a plurality of recesses 98 are equally spaced and circumferentially around the driver head hub 74 so as to be symmetrically arranged. In this regard, three locking sliders 80 are spaced 120° from each other around the axial center of the driver head hub 74 so as to be positioned at 0°, 120° and 240° around the axial center. A plurality of recesses 98 are symmetrically arranged around the driver head hub 74, and therefore the locking sliders 80 are symmetrically arranged. Self-centering of the driver head 20 within the hub 22 of the rotor 12 is provided, as will be described in further detail below. Although the driver head hub 74 includes three locking sliders 80, fewer or more locking sliders 80 may be provided. For example, the driver head hub 74 may include four locking sliders 80, which are spaced 90° from each other around the axial center of the driver head hub 74 so as to be positioned at 0°, 90°, 180° and 270° around the axial center.

[0050] As briefly described above, each locking slider 80 is movable in a radially inward direction and a radially outward direction within the corresponding recess 98 relative to the rotation axis A1 of the centrifuge drive 14. In particular, the elastic element 102 is located between each locking slider 80 and the drive head hub 74 to bias each locking slider 80 in a radially outward direction relative to the rotation axis A1 of the centrifuge drive 14. Figure 3 As shown, for example, the resilient element 102 can be a compression spring sandwiched between a substantially flat base surface 104 of each locking slide 80 and a substantially flat base surface 106 of each recess 98. To this end, the base surface 104 of the locking slide 80 can include a blind hole 108 formed therein, and the base surface 106 of the recess 98 can include a blind hole 110 formed therein, each blind hole being configured to receive a respective end of the compression spring, such as Figure 8 shown.

[0051] Reference Figure 8 , each locking slide 80 is generally "T" shaped in cross-section and includes a centrally located protrusion 112 defining a pair of shoulders 114. The protrusion 112 and the pair of shoulders 114 extend between a substantially flat top surface 116 and a substantially flat base surface 118 of each locking slide 80. The pair of shoulders 114 are configured to engage corresponding abutment surfaces 120 defined by the recesses 98 to provide a stop to prevent the locking slide 80 from over-extending from each recess 98. Figure 4 and Figure 5 As best shown in the figures, each locking slide 80 has a material thickness (i.e., the material thickness measured between the base surface 106 and the shoulder surface 114 of the locking slide 80) at each shoulder 114 that is less than the depth of each recess 98 (i.e., the distance between the base surface 104 and the adjacent surface 120 of each recess 98) to provide a certain range of radial movement of the locking slide 80 within the recess 98.

[0052] For example, Figure 4 and Figure 5 As shown, the protrusion 112 of each locking slider 80 defines a curved outer surface 122 that substantially matches the curvature of the second tubular sidewall 60 of the hub 22. To this end, each locking slider 80 is movable between at least a first compressed position and a second extended position, in which each locking slider 80 is received in a corresponding one of the plurality of recesses 98 in a radially inward direction relative to the rotation axis A1 of the centrifuge drive 14 to define a first outer diameter of the drive head hub 74, and in which each locking slider 80 (particularly each protrusion 112) extends a distance from a corresponding one of the plurality of recesses 98 in a radially outward direction relative to the rotation axis A1 of the centrifuge drive 14, so that the locking slider 80 defines a second outer diameter (e.g., greater than the first outer diameter) of the drive head hub 74. Figure 4 and Figure 5 ).

[0053] like Figure 2 and Figure 2A As shown, each locking slide 80 also includes a chamfered surface 124 extending between the curved outer surface 122 and the top surface 116 to facilitate insertion of the drive head 20 into the hub 22 of the centrifuge rotor 12, as described in further detail below. To this end, the curved outer surface 122 extends from the base surface 118 of the locking slide 80 to the chamfered surface 124, and the chamfered surface 124 extends from the top surface 116 to the curved outer surface 122 of the locking slide 80. The transition between the base surface 118 and the curved outer surface 122 can be rounded to form a rounded edge 125. As shown in FIG. Figure 2A As shown in FIG, the chamfered surface 124 extends from the top surface 116 to the curved outer surface 122 at an angle θ1 between 5° and 30° relative to the vertical direction (eg, the rotation axis A1). In the illustrated embodiment, the angle θ1 is between 5° and 30°.

[0054] Reference Figure 1-Figure 3A and Figure 8 , the crown 76 is configured to be attached to the driver head hub 74 and includes a recess 126 formed in a base 128 of the crown 76 that is configured to receive the boss 90 of the driver head hub 74 therein for coupling the crown 76 to the driver head hub 74. When the crown 76 is coupled to the driver head hub 74 (e.g., Figure 3 ), the boss 90 of the driver head hub 74 is completely contained in the recess 126 of the crown 76, thereby placing the base 128 of the crown 76 in engagement with the top surface 92 of the driver head hub 74. To this end, the fit between the recess 126 of the crown 76 and the boss 90 of the driver head hub 74 can be, for example, an interference fit. The crown 76 also includes a plurality of torque grooves 130 formed in the top surface 132 of the crown 76, each torque groove 130 being configured to receive a corresponding drive pin 66 therein to transmit the rotational motion of the centrifuge driver 14 to the centrifuge rotor 12, as described in further detail below. The center hole 82 formed in the crown 76 extends in an axial direction between the top surface 132 of the crown 76 and the recess 126, and can include a countersunk hole formed in the top surface 132, which is configured to receive the head of the fastener 72 therein, as shown.

[0055] Continue to refer to Figure 1-Figure 3A and Figure 8 , the retaining plate 78 is generally shaped as an annular disk and is configured to be attached to the base 96 of the driver head hub 74 to limit axial movement of each of the plurality of locking slides 80 within each corresponding recess 98 formed in the driver head hub 74. In this regard, each locking slide 80 is movable in a radial direction within each recess 98 so that the top surface 116 of each locking slide 80 can slidably engage the base surface 128 of the crown 76, and the bottom surface 118 of each locking slide 80 can slidably engage the top surface 134 of the retaining plate 78. In one embodiment, a first friction reducing insert can be positioned between each locking slide 80 and the base surface 128 of the crown 76, and a second friction reducing insert can be positioned between each locking slide 80 and the top surface 134 of the retaining plate 78. The friction reducing inserts can be made of an engineering plastic (e.g., ) or any other suitable low friction material. The retaining plate 78 is attached to the driver head hub 74 using fasteners 140, which are received through corresponding mounting holes 142 formed in the retaining plate 78. The fasteners 140 may be, for example, screws or bolts, and each mounting hole 142 may include a countersunk hole configured to receive the head of the fastener 140 therein, such as Figure 3 shown.

[0056] Now that certain details of the rotor 12 and drive head 20 of the centrifuge 10 have been described, the following will now be described in conjunction with Figure 1-Figure 3A The tool-free engagement between the driver head 20 and the hub 22 of the rotor 12 is described. In this regard, as Figure 2 As shown, when the rotor 12 is to be connected with the driver head 20, the rotor 12 is positioned above the driver head 20 to align the driver head 20 within the hub 22 of the rotor 12, and specifically the crown 76. The rotor 12 is then moved downwardly, as indicated by directional arrow A2, until the annular lip 62 engages with each locking slide 80. In particular, the annular lip 62 first engages with the chamfered surface 124 of each locking slide 80. The lowering of the rotor 12 and the continued engagement between the annular lip 62 and the chamfered surface 124 of each locking slide 80 cause the locking slide 80 to move in a radially inward direction into each corresponding recess 98, as indicated by directional arrow A3.

[0057] The open end 48 of the rotor hub 22 can slide past the locking slide 80 during further lowering of the rotor 12 in the axial direction A2 until the crown 76 is received in the crown receiving portion 52 of the rotor hub 22 and the driver head hub 20 is received in the driver head hub receiving portion 54 of the rotor hub 22, as shown. Figure 3 In this regard, the mating profiles of the crown receiving portion 52 and the crown 76 serve to align the drive head 20 within the rotor hub 22 as the rotor 12 is lowered over the drive head 20. In this manner, as the rotor 12 is lowered along the axial direction A2, the drive pin 66 is properly positioned within the corresponding torque slot 130 in the crown 76 for transmitting the rotational motion of the centrifuge drive 14 to the centrifuge rotor 12, as described in further detail below.

[0058] like Figure 3As shown, once the annular lip 62 passes the base surface 118 of each locking slider 80, each locking slider 80 moves in a radially outward direction, as shown by directional arrow A4, due to the elastic force exerted on each locking slider 80 by the elastic element 102, to place the curved outer surface 122 of each locking slider 80 into engagement with the second side wall 60 of the rotor hub 22. In this regard, the elastic force acting on each locking slider 80 is substantially perpendicular to the rotation axis A1, as shown in the figure. The symmetrical arrangement of the locking sliders 80 combined with the elastic force acting on each locking slider 80 causes a self-centering effect of the drive head 20 within the rotor hub 22. To this end, the drive head 20 can be received in the rotor hub 22 for coupling the rotor 12 to the centrifuge drive 14 in a tool-free manner without the need for additional assembly features or actuators to, for example, depress the locking slider 80.

[0059] like Figure 3 and Figure 3A As shown, when the driver head 20 is fully seated in the rotor hub 22, the radiused edge 125 of each locking slider 80 engages the upper radiused portion of the annular lip 62 of the rotor hub 22. The tangent plane T1 represents the plane defined by the surfaces of the curved edge 125 of each locking slider 80 and the upper radiused portion of the annular lip 62 that are in contact. As shown, the tangent plane T1 is angled relative to the horizontal plane to define a pressure angle θ2 that is less than 45°. In the illustrated embodiment, the pressure angle θ2 is 38°, however, other preferred angles for θ2 are, for example, 25° and 42°. During the removal of the rotor 12 from the driver head 20, a lifting force F is generated. L A lifting force F is generated between the hub 22 of the rotor 12 and each locking slider 80 along the contact line therebetween. Due to the engagement between the hub 22 of the rotor 12 and each locking slider 80, a lifting force F L Decomposed into the following components: and For this purpose, the pressure angle θ2 must be less than 45°, since the vertical component F L2 Should be smaller than the horizontal component F L1 , so that the rotor 12 can be removed from the locking head 20 by hand with minimal effort. During rotation of the rotor 12 by the driver head 20, the resultant forces between each locking slider 80 and the rotor hub 22 are balanced to produce a balanced force vector summation.

[0060] Now refer to Figure 4 and Figure 5, and as briefly described above, each locking slider 80 is configured to exert a radially outwardly directed force on the hub 22 of the rotor 12 that increases as the rotational speed of the drive head 20 increases. The radially outwardly directed force exerted by each locking slider 80 on the hub 22 of the rotor 12 is used to prevent axial movement of the centrifuge rotor 12 along the rotational axis A1 of the centrifuge drive 14 and rotational movement of the centrifuge rotor 12 relative to the drive head 20. In this regard, Figure 4 The contact force between each locking slider 80 and the hub 22 when the rotor 12 is stationary is shown. When the curvature of the curved outer surface 122 of each locking slider 80 matches or coincides with the curvature of the second side wall 60 of the rotor hub 22, the entire curved outer surface 122 of each locking slider 80 engages the second side wall 60. As a result, the elastic force from the elastic element 102 acting on each locking slider 80 is distributed on the curved outer surface 122 of each locking slider 80 to generate a first radial contact force between the curved outer surface 122 of each locking slider 80 and the second side wall 60, as shown by the direction arrow A5. For this purpose, the contact force A5 is perpendicular to the rotation axis A1.

[0061] Figure 5 The contact force between each locking slider 80 and the hub 22 is shown as shown by the direction arrow A6 when the rotor 12 rotates at a certain speed. During the rotation of the rotor 12 through the driver head 20, a second contact force is generated between each locking slider 80 and the hub 22, as shown by the direction arrow A7, which is greater than the above-mentioned second contact force. Figure 4 More specifically, the second contact force A7 is the elastic force from the elastic element 102 as described above and the centrifugal force component F based on the rotation speed of the driver head 20. c As shown in the figure, the second contact force A7 is also distributed between the curved outer surface 122 and the second side wall 60 of each locking slider 80. The centrifugal force component F of each slider c It can be determined using the following formula: c =m*r*Ω 2 Wherein, "m" is the weight of the locking slider 80, "r" is the distance between the rotation axis A1 of the rotor 12 and the center of mass of the locking slider 80, and "Ω" is the rotation speed of the rotor 12. As the rotation speed of the drive head 20 increases, and therefore the rotation speed of the rotor 12 increases, the centrifugal force component F acting on each locking slider 80 increases. c The combined centrifugal force (F ) applied by the locking sliders 80 to the rotor hub 22 is also increased, thereby increasing the second contact force A7 between each locking slider 80 and the hub 22. Tests were conducted on a prototype of the centrifuge 10 assembly described above to determine the combined centrifugal force (F ) applied by the locking sliders 80 to the rotor hub 22. c *3). Table 1 below shows these test results. Table 1 To this end, the deceleration of the rotor 12 reduces the second contact force A7 between each locking slide 80 and the hub 22 .

[0062] The contact forces A5, A7 between each locking slider 80 and the hub 22 cause a static friction coefficient F between each locking slider 80 and the side wall 60 of the rotor hub 22. sf (e.g. radial holding force and axial holding force, also called friction force). In this regard, the static friction coefficient F sc is a function of the coefficient of friction "μ" between the contact surfaces 122, 60 and the contact forces A5, A7. That is, F sf =μ*F c . Generally, as the contact forces A5, A7 increase with increasing speed of the rotor 12, the coefficient of static friction Fsf (radial retaining force and axial retaining force) also increases. Since the hub 22 of the rotor 12 and each locking slider 80 can be formed of steel (e.g., 316L stainless steel), the coefficient of friction μ between the curved outer surface 122 of each locking slider 80 and the side wall 60 of the rotor hub 22 can be, for example, between 0.3 and 0.5. However, the surface roughness of the curved outer surface 122 of each locking slider 80 and the side wall 60 of the rotor hub 22 can be changed to improve the coefficient of friction μ therebetween. For example, the surfaces 122, 60 can be machined and processed with different Ra (average roughness) (e.g., 15Ra) so that the coefficient of friction μ therebetween is in the range of, for example, between 0.3 and 0.8.

[0063] In view of the above, the weight of each locking slider 80 is an important design requirement for the operation of the drive head 20. In this regard, especially at lower rotation speeds of the rotor 12, the weight of each locking slider 80 should be as heavy as possible to increase F sf To this end, the three locking sliders 80 design provides a self-centering effect of the driver head hub 20 and a large size and mass of each locking slider 80. Therefore, although it is possible to have fewer or more locking sliders 80, such as two or four, each design sacrifices the self-centering effect (e.g., two locking sliders 80) or requires a smaller size and therefore smaller mass of each locking slider 80 (e.g., four locking sliders 80).

[0064] During the above-described testing, another advantage of the connection between drive head 20 and rotor 12 during operation of centrifuge 10 was observed. In this regard, centrifuge 10 was observed to be exceptionally quiet during operation, with a decibel (dB) output of 57.6 dB measured at 10,000 rpm.

[0065] Now refer to Figure 3 and Figure 6-Figure 8, when the driver head 20 is completely seated in the rotor hub 22, as Figure 3 As shown, the rotor 12 is considered to be mounted to the centrifuge drive 14. When so positioned, the drive pin 66 is received within the corresponding torque slot 130 and is configured to engage the side wall 144 of each corresponding torque slot 130 to minimize movement of the drive head 20 relative to the rotor 12 during initial acceleration or deceleration of the rotor 12 through the drive 14. The engagement between the drive pin 66 and the torque slot 130 can also transfer the rotational motion of the centrifuge drive 14 to the centrifuge rotor 12 during initial acceleration or deceleration of the rotor 12 through the drive 14. As shown in FIG. Figure 6-Figure 8 As shown, the torque grooves 130 are formed as oblong arc-shaped blind holes having a slightly curved profile that substantially conforms to the circumference of a top surface 132 of the crown 76. In this regard, the torque grooves 130 are formed in the top surface 132 of the crown 76 and are circumferentially spaced in an end-to-end symmetrical arrangement around the hole 82 formed through the axial center of the crown 76. For this purpose, although the crown 76 includes five torque grooves 130, fewer or more torque grooves 130 may be provided.

[0066] like Figure 6 and Figure 7 As shown, the driver head 20 is completely seated within the rotor hub 22 such that the first drive pin 66 is positioned in abutment or near abutment with the leftmost arcuate portion 146 of the side wall 144 of the first torque slot 130 (i.e., the leftmost portion of the torque slot side wall 144 measured in a radial direction around the axial center of the crown 76), and the second drive pin 66 is positioned in abutment or near abutment with the rightmost arcuate portion 148 of the side wall 144 of the second torque slot 130 (i.e., the rightmost portion of the torque slot side wall 144 measured in a radial direction around the axial center of the crown 74). As shown, the first drive pin 66 and the second drive pin 66 do not abut the arcuate portion 146 of the side wall 144 of the first torque slot 130 and the arcuate portion 148 of the side wall of the second torque slot at the same time. Instead, only one of the drive pins 60 is in abutment with the respective arcuate portion 146, 148 of the torque slot side wall 144, depending on whether the rotor 12 is accelerating or decelerating. This configuration allows for a smaller gap to be formed between the unengaged drive pin 60 and the corresponding side wall 144 , as described in further detail below.

[0067] Figure 6The rotor 12 is shown being accelerated to a particular rotational speed by the driver head 20, as indicated by directional arrow A8. As shown, during acceleration, the first drive pin 66 is in abutment with the leftmost arcuate portion 146 of the side wall 144 of the first torque slot 130 to transfer torque from the driver head 20 to the rotor 12, as indicated by directional arrow A9. To this end, the engagement between the first drive pin 66 and the first torque slot 130 prevents the driver head 20 from rotating relative to the rotor 12 during the acceleration of the rotor 12 by the centrifuge driver 14. Also during the acceleration of the rotor 12, the second drive pin 66 is spaced apart from the rightmost arcuate portion 148 of the side wall 144 of the second torque slot 130, so that a gap 150 is formed therebetween. The size of the gap 150 determines the range of motion, also referred to as rotational slip or play, of the rotor 12 in which it can rotate independently of the driver head 20.

[0068] Figure 7 The rotor 12 is shown during deceleration or braking of the rotor 12 by the driver 14. As shown by the directional arrow A10, the rotor 12 is moving at a speed less than Figure 6 14 and 15. In this regard, during deceleration of the rotor 12 by the driver 14, the second drive pin 66 is in abutment with the rightmost arcuate portion 148 of the side wall 144 of the second torque slot 130 to transfer torque from the drive head 20 to the rotor 12, as shown by the directional arrow A11. To this end, the engagement between the second drive pin 66 and the second torque slot 130 prevents rotation of the drive head 20 relative to the rotor 12 during deceleration of the rotor 12 by the centrifuge driver 14. Also during deceleration of the rotor 12, the first drive pin 66 is spaced apart from the leftmost arcuate portion 146 of the side wall 144 of the first torque slot 130 such that a gap 152 is formed therebetween. The size of the gap 152 may be similar to that described above with respect to Figure 6 Gap 150 is described.

[0069] Reference now Figure 9-12, wherein the same reference numerals represent the same features, another exemplary centrifuge 10a according to a second embodiment of the present invention is shown, which does not have any substructure. Centrifuge 10a includes a centrifuge rotor 160, which is operably connected to a centrifuge driver 14a, and the centrifuge driver has a drive shaft or spindle 16 driven by a motor 18, for rotating the rotor 160 around the axis of rotation A1 to achieve high-speed, centrifugal rotation of the rotor 160. As shown, the centrifuge driver 14a includes a drive head 20a positioned at one end of the spindle 16, which is configured to be received in a hub 162 of the rotor 160, for removably connecting the rotor 160 to the centrifuge driver 14a in a tool-free manner. The main difference between the centrifuge 10a of the present embodiment and the centrifuge 10 of the previously described embodiment is the construction of the drive head 20a. In order to adapt to the different constructions of the drive head 20a, the construction of the hub 162 of the rotor 160 is also different compared to the aforementioned embodiment.

[0070] Reference Fig. 9 , an exemplary centrifuge rotor 160 includes a rotor body 164 and a rotor cover 166, the rotor cover being configured to be coupled to an open end of the rotor body 164, and the rotor body 164 is symmetrical about a common rotation axis A1 with the centrifuge drive 14a. The rotor 160 includes a plurality of rotor wells 168 (also referred to as receiving chambers or cell well cavities) formed in the rotor body 164 and radially distributed around a vertical hole 170 formed through the axial center of the rotor 160 in a symmetrical arrangement. Each rotor well 168 formed in the rotor body 164 is substantially cylindrical in shape and is configured to receive a sample container (not shown) therein to centrifuge a sample held in the sample container. Each rotor well 168 can be formed in the rotor body 164 so as to have a fixed angular relationship relative to the rotation axis A1 of the rotor 160, and the rotor 160 can be considered, for example, as a high-speed angle-fixed rotor.

[0071] Continue to refer to Fig. 9 , the rotor 160 includes a rotor insert 172 disposed within a central interior region of the rotor body 164, the rotor insert being configured to threadedly engage with the rotor hub 162. In this regard, the rotor insert 172 is positioned about the rotation axis A1 and is configured to receive and threadedly engage the rotor hub 162 to hold the rotor hub 162 in position within the vertical bore 170 of the rotor 160. The engagement between the rotor insert 172 and the rotor hub 162 exposes an externally threaded top portion 174 of the hub 162 from the vertical bore 170, to which a hub retainer 176 is threadedly fastened to hold the hub 162 in position relative to the rotor body 164.

[0072] The rotor 160 also includes a cap screw 178 for securing the rotor cover 166 to the rotor body 164. The cap screw 178 is configured to be screwed into the internally threaded top portion 180 of the rotor hub 162, so that turning the cap screw 178 to engage the hub 162 presses the cap screw 178 down on the cover 166, thereby securing the cover 166 to the rotor 160. As shown, the cap screw 178, the hub 162, and the rotor insert 172 are coaxially arranged with the vertical hole 170 formed in the rotor body 164. To this end, the cover 166 seals and closes the open end of the rotor body 164 to prevent access to one or more sample containers held in the rotor well 168 during high-speed rotation of the rotor 160.

[0073] As shown, the hub 162 of the rotor 160 includes an internal cavity 182, which is configured to receive the driver head 20a of the centrifuge driver 14a therein for coupling the rotor 160 to the centrifuge driver 14a. In this regard, the shape of the cavity 182 generally corresponds to the shape of the driver head 20a. More specifically, the internal cavity 182 extends from the open end 184 of the hub 162 to the radially extending base surface 186 of the hub 162 in a stepped manner. In this regard, the internal cavity 182 is defined by a first tubular sidewall 188 extending from the base surface 186 of the hub 162 to the shoulder 190 and a second tubular sidewall 192 extending from the shoulder 190 to the open end 184 of the hub 162. For this purpose, the stepped profile of the rotor hub 162 is used to align the driver head 20a in the rotor hub 162 during the installation of the rotor 160 to the driver head 20a.

[0074] refer to Figure 9-12 , the base surface 186 of the rotor hub 162 includes a plurality of torque grooves 194 formed therein. Each torque groove 194 defines a sidewall 196 and is configured to receive a corresponding drive pin 66 of the drive head 20a therein to transfer the rotational motion of the centrifuge drive 14a to the centrifuge rotor 160, as described in further detail below. Fig.11 and Fig.12 As best shown in FIG. 1 , the torque slots 194 are formed as oblong arc-shaped blind holes having a slightly curved profile that substantially conforms to the circumference of the base surface 186 of the hub 162. In this regard, the torque slots 194 are formed in the base surface 186 of the rotor hub 162 and are circumferentially spaced in an end-to-end symmetrical arrangement about the axial center of the rotor hub 162. To this end, although the rotor hub 162 includes four torque slots 194, fewer or more torque slots 194 may be provided.

[0075] Reference Fig. 9 and Fig.10, the driver head 20a is mounted to the distal end 70 of the spindle 16 by a fastener 72, and includes a driver head hub 74, a crown 76a, and a retaining plate 78 coupled together in a coaxial arrangement. The crown 76a, the driver head hub 74, and the retaining plate 78 each include a central hole 198, 84, 86, respectively, which is configured to receive the fastener 72 therethrough for attaching the driver head 20a to the distal end 70 of the spindle 16. Similar to the above reference Figure 1-Figure 8 The driver head 20, the driver head hub 74 includes a plurality of radially movable locking sliders 80, which are configured to exert a radially outwardly directed force on the hub 162 of the rotor 160, which increases as the rotation speed of the driver head 20a increases. Each locking slider 80 is movably retained in a corresponding recess 98 formed in the outer side wall 100 of the driver head hub 74. The elastic element 102 is located between each locking slider 80 and the driver head hub 74, and each locking slider 80 is movable in the corresponding recess 98 along the radially inward direction and the radially outward direction relative to the rotation axis A1 of the centrifuge driver 14a. More specifically, each locking slider 80 is slidably engaged with the base surface 128a of the crown 76a and the top surface 134 of the retaining plate 78. To this end, each locking slider 80 is configured to exert a radially outwardly directed force on the second side wall 192 of the hub 162 of the centrifuge rotor 160, which force increases as the rotational speed of the drive head 20a increases, so as to prevent axial movement of the centrifuge rotor 160 along the rotation axis A1 of the centrifuge drive 14a and rotational movement of the centrifuge rotor 160 relative to the drive head 20a.

[0076] The crown 76a is configured to be attached to the driver head hub 74 and includes a recess 126a formed in the base 128a of the crown 76a that is configured to receive the boss 90 of the driver head hub 74 therein for coupling the crown 76a to the driver head hub 74. When the crown 76a is coupled to the driver head hub 74 (e.g., Fig. 9 and Fig.10 ), the boss 90 of the driver head hub 74 is fully received within the recess 126a of the crown 76a, thereby placing the base 128a of the crown 76a in engagement with the top surface 92 of the driver head hub 74. To this end, the fit between the recess 126a of the crown 76a and the boss 90 of the driver head hub 74 may be, for example, an interference fit.

[0077] The crown 76a has a generally stepped profile and includes an annular flange 200 that is configured to engage the top surface 92 of the drive head hub 74, as shown. A plurality of blind holes 202 are formed in the top surface 132a of the crown 76a that are configured to receive corresponding drive pins 66 therein. As shown, the drive pins 66 are configured to be received within corresponding torque slots 194 in the rotor hub 162 to transfer the rotational motion of the centrifuge driver 14a to the rotor 160, as described in further detail below. Fig.11 and Fig.12 As shown, the crown 76a includes a combination of three blind holes 202 and a drive pin 66. The combination of the blind holes 202 and the drive pin 66 is arranged around the rotation axis A1 (e.g., Fig. 9 ) The axial centers of the coaxial crowns 76a are spaced 120° apart from each other. However, the crown 76a may include fewer or more blind holes 202 and drive pin 66 combinations spaced apart in different configurations around the axial center of the crown 76a. For example, the crown 76a may include a combination of two blind holes 202 and a drive pin 66. In any case, the engagement between each drive pin 66 and the blind hole 202 is an interference fit, also known as a press fit. To this end, there may be a gap between the base of each blind hole 202 and the drive pin 66 to facilitate a press fit engagement therebetween, as shown. However, it should be understood that the drive pin 66 can be attached to the crown 76a in other ways, such as by welding. In one embodiment, the crown 76a and the drive pin 66 may be integrally formed as a single piece.

[0078] Reference Fig.11 and Fig.12 , the driver head 20a is completely seated within the rotor hub 162 such that the first drive pin 66 is positioned within the first torque slot 194, the second drive pin 66 is positioned within the second torque slot 194, and the third drive pin 66 is positioned within the third torque slot 194. In particular, the first drive pin 66 is in abutment or near abutment with a rightmost arcuate portion 204 of the side wall 196 of the first torque slot 194 (i.e., the rightmost portion of the torque slot side wall 196 measured in a radial direction around the axial center of the rotor hub 162), and the second drive pin 66 is positioned in abutment or near abutment with a leftmost arcuate portion 206 of the side wall 196 of the second torque slot 194 (i.e., the leftmost portion of the torque slot side wall 196 measured in a radial direction around the axial center of the rotor hub 162). The third drive pin 66 is centrally positioned within the third torque slot 194. Similar to the above description of Figure 1-Figure 8In the depicted embodiment, the first drive pin 66 and the second drive pin 66 do not abut both the arcuate portion 204 and the arcuate portion 206 of the sidewall 196 of the first torque slot 194. Instead, only one of the drive pins 66 is in abutting relationship with the respective arcuate portion 204, 206 of the sidewall 196 of the torque slot, depending on whether the rotor 160 is accelerating or decelerating.

[0079] Fig.11 The rotor 160 is shown accelerated to a particular rotational speed by the driver head 20a, as indicated by the directional arrow A12. As shown, during acceleration, the first drive pin 66 is in abutment with the rightmost arcuate portion 204 of the side wall 196 of the first torque slot 194 to transfer torque from the driver head 20a to the rotor 160, as indicated by the directional arrow A13. To this end, the engagement between the first drive pin 66 and the first torque slot 194 prevents the driver head 20a from rotating relative to the centrifuge rotor 160 during the acceleration of the centrifuge rotor 160 by the centrifuge driver 14a. Also during acceleration of the rotor 160, the second drive pin 66 is spaced apart from the leftmost arcuate portion 206 of the side wall 196 of the second torque slot 194, so that a gap 208 is formed therebetween.

[0080] Fig.12 The rotor 160 is shown during deceleration or braking, as indicated by directional arrow A14. In this regard, the rotor 160 is moving at a speed less than Fig.11 194 . As shown, during deceleration, the second drive pin 66 is in abutment with the leftmost arcuate portion 206 of the side wall 196 of the second torque slot 194 to transfer torque from the drive head 20a to the rotor 160, as shown by directional arrow A15. To this end, the engagement between the second drive pin 66 and the second torque slot 194 prevents rotation of the drive head 20a relative to the centrifuge rotor 160 during deceleration of the centrifuge rotor 160 by the centrifuge driver 14a. Also during deceleration of the rotor 160, the first drive pin 66 is spaced apart from the leftmost arcuate portion 204 of the side wall 196 of the first torque slot 194 such that a gap 210 is formed therebetween. Due to the construction of three drive pins 66 and four torque slots 194, the gaps 208, 210 are similar to those described above with reference to FIG. Figure 1-Figure 8 The described embodiment has smaller gaps 150, 152. As a result, during transient acceleration or braking of the rotor 160, slippage between the rotor 160 and the driver head 20a is negligible.

[0081] Now refer to Fig.13, wherein like reference numerals denote like features, details of an adapter 220 for attaching any of the above-described driver heads 20, 20a to a spindle 222 of a centrifuge (not shown) are shown according to another embodiment of the present invention, the spindle being of different dimensions than the spindle 16 of the above-described centrifuge 10, 10a. In this regard, the distal end 224 of the spindle 222 is smaller in diameter than the distal end 70 of the above-described spindle 16, and thus cannot be properly fitted within the recess 94 formed in the base 96 of the driver head hub 74. In another embodiment, an adapter may be provided to attach the driver head 20, 20a to a distal end 224 of a spindle that is larger in diameter than the distal end 70 of the above-described spindle 16. As described in further detail below, the adapter 220 is fitted to the distal end 224 of the spindle 222, and a portion of the adapter 220 is received within the recess 94 of the driver head hub 74, so that the driver head 20 can be operably coupled to the spindle 222.

[0082] Continue to refer Fig.13 , the adapter 220 includes a cup-shaped flange 226 and a mounting hole 228 that extends axially through the adapter 220 and extends between a first opening 230 leading to the mounting hole 228 formed in a first protrusion 232 of the adapter 220 and a second opening 234 leading to the mounting hole 228 formed in a second protrusion 236 of the adapter 220. The first protrusion 232 and the second protrusion 236 protrude from the flange in axially opposite directions so that the mounting hole 228 is formed through the axial center of the adapter 220. As shown, the axial center of the adapter 220 is coaxial with the rotation axis A16 of the spindle 222, the driver head 20, and the adapter 220. The diameter of the first opening 230 formed in the first protrusion 232 is smaller in size than the diameter of the second opening 234 formed in the second protrusion 236. In this regard, the diameter of the mounting hole 228 gradually decreases in size along the axial length of the mounting hole 228 and in a direction from the second opening 234 to the first opening 230. Thus, the mounting hole 228 is substantially truncated-conical in shape. To this end, the configuration of the mounting hole 228 may vary depending on the type of centrifuge being used.

[0083] As shown, the second opening 234 is configured to receive the distal end 224 of the spindle 222 therethrough, and the first opening 230 is configured to receive the fastener 238 therethrough for securing the adapter 220 and the driver head 20 to the spindle 222. In this regard, the distal end 224 of the spindle 222 is received into the mounting hole 228 through the second opening 234 to position the distal end 224 of the spindle 222 within the mounting hole 228, as shown. For example, the fit between the distal end 224 of the spindle 222 and the mounting hole 228 may be a friction fit to secure the adapter 220 to the spindle 222. To this end, the mounting hole 228 may have different configurations based on the configuration of the spindle 222. For example, the mounting hole 228 may have a constant diameter between the first opening 230 and the second opening 234.

[0084] As shown, the first protrusion 232 of the adapter 220 is substantially truncated cone-shaped and is sized to be received in the recess 94 of the driver head hub 74 to couple the driver head 20 to the adapter 220. That is, the outer contour of the first protrusion 232 substantially corresponds to the contour of the recess 94. The fit between the first protrusion 232 of the adapter 220 and the recess 94 of the driver head hub 74 may be, for example, a friction fit. The adapter 220 is configured to be sandwiched between the driver head 20 and the distal end 224 of the spindle 16 in a coaxial arrangement, as shown, wherein the driver head 20 and the adapter 220 are mounted to the distal end 70 of the spindle 222 using fasteners 238. To this end, a fastener 238, which may be a bolt or screw, for example, is received through the aligned holes 82, 84 and the mounting hole 228 of the adapter 220 and is screwed into the threaded hole 240 in the distal end 224 of the spindle 222 to secure the driver head 20 and the adapter 220 to the spindle 222.

[0085] Fig.14 An exemplary centrifuge 10, 10a is shown including a housing 212, a drive 14, 14a, and one of the above-described rotors 12, 160 coupled to the drive 14, 14a using one of the above-described drive heads 20, 20a. In operation, the drive 14, 14a imparts rotation to the spindle, which in turn provides a rotational torque to the rotor 12, 160 to rotate the rotor 12, 160 at a desired speed.

[0086] Although the present invention has been described by describing various embodiments of the present invention, and although the embodiments have been described in great detail, it is not intended that the scope of the appended claims be limited to such details or in any way limited to such details. Therefore, the various features discussed herein may be used alone or in any combination. Additional advantages and modifications will be clear to those skilled in the art. Therefore, the present invention in its broader aspects is not limited to the specific details and illustrative examples shown and described. Therefore, such details may be deviated from without departing from the scope of the general concept of the present invention.

Claims

1. A drive head for a centrifuge drive, the drive head being configured to be received in a hub of a centrifuge rotor for coupling the centrifuge rotor to the centrifuge drive so that the centrifuge rotor is rotated by the centrifuge drive about a rotation axis of the centrifuge drive, the hub of the centrifuge rotor having at least one drive pin for transmitting the rotational motion of the centrifuge drive to the centrifuge rotor, the drive head comprising: a drive head hub including a central bore configured to receive a fastener therethrough to couple the drive head to a spindle of the centrifuge drive, the drive head hub comprising: a plurality of recesses formed in an outer sidewall of the driver head hub and spaced circumferentially and symmetrically about the driver head hub; a locking slide movably retained within each of the plurality of recesses and movable within the recess in a radially inward direction and a radially outward direction relative to the rotational axis of the centrifuge drive; and a resilient element located between each locking slide and the drive head hub for biasing each locking slide in the radially outward direction relative to the rotational axis of the centrifuge drive, Each locking slider is configured to exert a radially outwardly directed force on the inner side wall of the hub of the centrifuge rotor to prevent axial movement of the centrifuge rotor along the rotation axis of the centrifuge drive and rotational movement of the centrifuge rotor relative to the drive head, wherein the radially outwardly directed force increases with increasing rotational speed of the drive head.

2. The drive head according to claim 1, characterized in that: Also includes: a crown attached to a top of the driver head hub, the crown including a central bore configured to receive the fastener therethrough and a plurality of torque slots formed in a top surface of the crown, the central bore configured to receive at least one drive pin of the hub of the centrifuge rotor to transfer rotational motion of the centrifuge drive to the centrifuge rotor; and A retention plate is attached to a base of the driver head hub, the retention plate including a central aperture configured to receive a distal end of the spindle therethrough.

3. The driver head according to claim 1, characterized in that: Each locking slide comprises a curved outer surface in cross section which matches in cross section the curvature of the inner side wall of the hub of the centrifuge rotor.

4. The driver head according to claim 3, characterized in that: Each locking slide includes a chamfered surface extending between the curved outer surface and a top surface of each locking slide to facilitate insertion of the drive head into the hub of the centrifuge rotor.

5. The driver head according to claim 1, characterized in that: Each locking slider can be moved between the following positions: a first position wherein each locking slide is received within a corresponding one of the plurality of recesses in a radially inward direction relative to the rotational axis of the centrifuge drive to define a first outer diameter of the drive head hub; and A second position wherein each locking slide protrudes a distance from the corresponding one of the plurality of recesses in a radially outward direction relative to the rotational axis of the centrifuge drive to define a second outer diameter of the drive head hub, the second outer diameter being greater than the first outer diameter.

6. The driver head according to claim 1, characterized in that: The plurality of recesses are equally spaced around the circumference of the drive head hub to provide self-centering of the drive head within the centrifuge rotor hub by each locking slide.

7. The driver head according to claim 2, characterized in that: Each locking slide slidably engages a base surface of the crown and a top surface of the retaining plate.

8. The driver head of claim 1, wherein each locking slide includes a pair of shoulders configured to engage an abutment surface of each recess to prevent the locking slide from over-extending from each recess by the resilient element.

9. The driver head according to claim 2, characterized in that: The driver head hub includes a boss protruding upward from a top surface of the driver head hub, the boss being configured to be received within a recess formed in a base of the crown for coupling the driver head hub to the crown.

10. The driver head according to claim 9, characterized in that The fit between the boss of the driver head hub and the recess of the crown is an interference fit.

11. The driver head according to claim 2, characterized in that: Each torque slot is an arc-shaped blind hole.

12. The driver head according to claim 11, characterized in that The plurality of torque grooves are spaced circumferentially about the central bore of the crown.

13. The driver head according to claim 2, characterized in that A first drive pin of the hub of the centrifuge rotor is configured to engage a sidewall of a first torque slot to prevent rotation of the drive head relative to the centrifuge rotor during acceleration of the centrifuge rotor by the centrifuge drive.

14. The driver head according to claim 13, characterized in that A second drive pin of the hub of the centrifuge rotor is configured to engage a sidewall of a second torque slot to prevent rotation of the drive head relative to the centrifuge rotor during deceleration of the centrifuge rotor by the centrifuge drive.

15. A centrifuge comprising: The driver head according to claim 1; and A centrifuge rotor comprising a hub configured to receive the drive head therein, the hub comprising at least one drive pin protruding from an inner surface of the hub in an axially downward direction relative to an axis of rotation of the centrifuge drive, the at least one drive pin configured to transmit rotational motion of the centrifuge drive to the centrifuge rotor.

16. A drive head for a centrifuge drive, the drive head being configured to be received within a hub of a centrifuge rotor for coupling the centrifuge rotor to the centrifuge drive such that the centrifuge rotor is rotated by the centrifuge drive about an axis of rotation of the centrifuge drive, the hub of the centrifuge rotor having at least one torque slot formed therein, the drive head comprising: a drive head hub including a central bore configured to receive a fastener therethrough to couple the drive head to a spindle of the centrifuge drive, the drive head hub comprising: a plurality of recesses formed in an outer sidewall of the driver head hub and spaced circumferentially and symmetrically about the driver head hub; a locking slide movably retained within each of the plurality of recesses and movable within the recess in a radially inward direction and a radially outward direction relative to the rotational axis of the centrifuge drive; and a resilient element located between each locking slide and the drive head hub for biasing each locking slide in the radially outward direction relative to the rotational axis of the centrifuge drive; and a crown attached to a top of the driver head hub, the crown including a central bore configured to receive a fastener therethrough, and at least one drive pin configured to engage the at least one torque slot formed in the hub of the centrifuge rotor to transfer rotational motion of the centrifuge drive to the centrifuge rotor, Each locking slider is configured to exert a radially outwardly directed force on the inner side wall of the hub of the centrifuge rotor to prevent axial movement of the centrifuge rotor along the rotation axis of the centrifuge drive and rotational movement of the centrifuge rotor relative to the drive head, wherein the radially outwardly directed force increases with increasing rotational speed of the drive head.

17. The driver head according to claim 16, characterized in that Also included is a retention plate attached to a base of the driver head hub, the retention plate including a central aperture configured to receive a distal end of the spindle therethrough.

18. The driver head according to claim 16, characterized in that Each locking slide comprises a curved outer surface in cross section which matches in cross section the curvature of an inner side wall of the hub of the centrifuge rotor.

19. The driver head according to claim 18, characterized in that Each locking slide includes a chamfered surface extending between the curved outer surface and a top surface of each locking slide to facilitate insertion of the drive head into the hub of the centrifuge rotor.

20. The driver head according to claim 16, wherein: Each locking slider can be moved between the following positions: a first position wherein each locking slide is received within a corresponding one of the plurality of recesses in a radially inward direction relative to the rotational axis of the centrifuge drive to define a first outer diameter of the drive head hub; and A second position wherein each locking slide protrudes a distance from the corresponding one of the plurality of recesses in a radially outward direction relative to the rotational axis of the centrifuge drive to define a second outer diameter of the drive head hub, the second outer diameter being greater than the first outer diameter.

21. The driver head according to claim 16, characterized in that The plurality of recesses are equally spaced around the circumference of the drive head hub to provide self-centering of the drive head within the hub of the centrifuge rotor by each locking slide.

22. The driver head according to claim 17, wherein: Each locking slide slidably engages a base surface of the crown and a top surface of the retaining plate.

23. The driver head according to claim 16, characterized in that Each locking slide includes a pair of shoulders configured to engage with an abutment surface of a corresponding one of the plurality of recesses to prevent over-extension of the locking slide from the corresponding one of the plurality of recesses.

24. The driver head according to claim 16, characterized in that The at least one drive pin includes a first drive pin, a second drive pin, and a third drive pin spaced circumferentially about the central bore of the crown.

25. A centrifuge comprising: The driver head according to claim 16; and A centrifuge rotor comprising a hub configured to receive the drive head therein, the hub comprising at least one torque slot formed therein, the at least one torque slot configured to receive at least one drive pin of the crown for transmitting rotational motion of the centrifuge drive to the centrifuge rotor.

26. The driver head according to claim 25, characterized in that Each torque slot is an arc-shaped blind hole.

27. The driver head according to claim 26, characterized in that The at least one torque slot includes four torque slots spaced circumferentially about a central bore formed in the hub.

28. The driver head according to claim 25, characterized in that The first drive pin of the crown is configured to engage a sidewall of the first torque slot to prevent rotation of the drive head relative to the centrifuge rotor during acceleration of the centrifuge rotor by the centrifuge drive.

29. The driver head according to claim 28, characterized in that A second drive pin of the crown of the centrifuge rotor is configured to engage a sidewall of a second torque slot to prevent rotation of the drive head relative to the centrifuge rotor during deceleration of the centrifuge rotor by the centrifuge drive.

30. An adapter for mounting a drive head to a spindle of a centrifuge drive, the drive head being configured to be received within a hub of a centrifuge rotor for coupling the centrifuge rotor to the centrifuge drive such that the centrifuge rotor is rotated by the centrifuge drive about an axis of rotation of the centrifuge drive, the drive head including a central bore configured to receive a fastener therethrough to couple the drive head to a distal end of a spindle of the centrifuge drive, the adapter comprising: a first protrusion configured to be received within a recess formed in the driver head; a second protrusion, the second protrusion protruding in a direction opposite to the axial direction of the first protrusion; and a mounting hole extending axially through the adapter and between a first opening to the mounting hole formed in the first projection of the adapter and a second opening to the mounting hole formed in the second projection of the adapter, wherein the mounting hole is configured to receive a distal end of the spindle through the second opening such that the central hole of the drive head, the mounting hole, and the threaded hole in the distal end of the spindle are coaxially arranged to receive the fastener therethrough to couple the drive head and the adapter to the distal end of the spindle of the centrifuge drive.

31. The adapter according to claim 30, characterized in that Also included is a cup-shaped flange located axially between the first protrusion and the second protrusion.

32. The adapter according to claim 30, characterized in that The first protrusion is truncated cone in shape.

33. The adapter according to claim 30, characterized in that The mounting hole is truncated cone in shape.

Images