Cog-based mechanism for generating an orbital shaking motion

Abstract

A mechanism for generating an orbital motion for mixing a fluidic sample. The mechanism may comprise a first and second cogwheel each having a through hole and a plurality of cogs. A drive shaft having a concentric first section and an eccentric second section is guided through a respective through hole of the first and second cogwheel. A coupling body engages part of the cogs to thereby generate the orbital motion of the second cogwheel and a sample holder to be mounted so as to follow a motion of the second cogwheel upon rotating the first section of the drive shaft.

Claims

1. A mechanism for generating an orbital motion for mixing a fluidic sample accommodated by a sample holder, the mechanism comprising: a stationary mounted or lockable first cogwheel having a first through hole and a plurality of first cogs arranged along an outer circumference of the first cogwheel; a movably mounted second cogwheel having a second through hole and a plurality of second cogs arranged along an outer circumference of the second cogwheel; a drive shaft having a concentric first section and an eccentric second section, wherein the first section is guided through the first through hole and the second section is guided through the second through hole; and a coupling body having a plurality of third cogs arranged along an inner circumference of the coupling body, wherein the coupling body is mounted with the first cogwheel and with the second cogwheel to engage part of the first cogs and part of the second cogs by part of the third cogs to thereby generate the orbital motion of the second cogwheel and a sample holder to be mounted so as to follow a motion of the second cogwheel upon rotating the first section of the drive shaft.

2. The mechanism according to claim 1, wherein each of the first cogwheel and the second cogwheel is a toothed belt disc and the coupling body is a toothed belt.

3. The mechanism according to claim 1, wherein each of the first cogwheel and the second cogwheel is a sprocket and the coupling body is a sprocket chain.

4. The mechanism according to claim 1, wherein the coupling body is a flexible structure being deformable but basically non-elongatable upon rotating the drive shaft so as to adapt its shape to follow motion of the second cogwheel while maintaining the coupling between the first cogwheel and the second cogwheel.

5. The mechanism according to claim 1, wherein the coupling body is a rigid, non-deformable structure which, upon rotating the drive shaft, follows, as a whole, motion of the second cogwheel while maintaining the coupling between the first cogwheel and the second cogwheel.

6. The mechanism according to claim 1, wherein the coupling body is an annular structure having an inner diameter which is larger than an outer diameter of the first cogwheel and the second cogwheel by one times of an eccentricity (r0) of the second section of the drive shaft, wherein the largest inner extension of the coupling body equals to an outer diameter of the first cogwheel or the second cogwheel plus an eccentricity (r0) of the second section of the drive shaft.

7. The mechanism according to claim 1, comprising a support body on which the second cogwheel, the drive shaft and the coupling body are mounted, wherein the first cogwheel is configured as an integral portion of the support body.

8. The mechanism according to claim 1, wherein the coupling body is mounted with the first cogwheel and with the second cogwheel so as to form a form closure which superposes, to a rotating motion of the second cogwheel transmitted by the drive shaft, a rolling motion of the second cogwheel during which the second cogwheel rolls up on the coupling body limited by a rolling motion during which the coupling body rolls up on the first cogwheel.

9. The mechanism according to claim 1, comprising a drive unit being configured for rotating the first section of the drive shaft.

10. The mechanism according to claim 1, comprising a compensation weight mounted asymmetrically on the drive shaft and being configured so as to at least partially compensate for a mechanical load acting on the drive shaft upon generating the orbital motion.

11. The mechanism according to claim 1, configured for switching the sample holder for accommodating the fluidic sample between an orbital motion mode for sample mixing in which the orbital motion is performed, and a rotary motion mode for sample separation wherein the first cogwheel in a locked stationarily mounted state, the second cogwheel, the drive shaft and the coupling body form an orbital motion generator configured for generating the orbital motion of the sample holder when being operated in the orbital motion mode; the mechanism further comprising: a gear element being drivable by a drive unit to move selectively in a first direction or in a second direction being inverse to the first direction; a rotary motion generator configured for generating a rotary motion of the sample holder when being operated in the rotary motion mode; and a one-way clutch arrangement configured for selectively: coupling the gear element with the orbital motion generator to transfer a driving force from the gear element to the orbital motion generator for generating the orbital motion when the gear element is driven in the first direction and to freewheel when the gear element is driven in the second direction; or coupling the gear element with the rotary motion generator to transfer a driving force from the gear element to the rotary motion generator for generating the rotary motion when the gear element is driven in the second direction and to freewheel when the gear element is driven in the first direction.

12. The mechanism according to claim 11, wherein the one-way clutch arrangement comprises: a first one-way clutch configured for coupling the gear element with the orbital motion generator to transfer the driving force from the gear element to the orbital motion generator for generating the orbital motion when the gear element is driven in the first direction and to freewheel when the gear element is driven in the second direction; and a second one-way clutch configured for coupling the gear element with the rotary motion generator to transfer the driving force from the gear element to the rotary motion generator for generating the rotary motion when the gear element is driven in the second direction and to freewheel when the gear element is driven in the first direction.

13. The mechanism according to claim 12, wherein the first one-way clutch and the second one-way clutch freewheel in mutually opposite directions and transmit force in mutually opposite directions.

14. The mechanism according to claim 12, wherein the first one-way clutch is arranged between an interior curved surface of the gear element configured as a hollow shaft and an exterior curved surface of a drive shaft of the orbital motion generator.

15. The mechanism according to claim 12, wherein the second one-way clutch is arranged between an exterior curved surface of the gear element configured as a hollow shaft and an interior curved surface of a movably mounted cogwheel of the rotary motion generator.

16. The mechanism according to claim 11, wherein the rotary motion generator comprises the second cogwheel, the coupling body and the selectively lockable first cogwheel in an unlocked movably mounted state and being coupled to the gear element via the one-way clutch arrangement, and wherein the coupling body is mounted with the first cogwheel and with the second cogwheel to engage part of the first cogs and part of the second cogs by part of the third cogs to thereby generate the rotary motion of the second cogwheel and a sample holder to be mounted so as to follow a motion of the second cogwheel upon rotating the gear element in the second direction.

17. The mechanism according to claim 16, further comprising a cogwheel locking element configured for selectively locking the first cogwheel in the locked stationarily mounted state or for unlocking the first cogwheel in the unlocked movably mounted state.

18. The mechanism according to claim 11, further comprising a shaft locking element configured for selectively locking the drive shaft in a locked stationarily mounted state or for unlocking the drive shaft in an unlocked movably mounted state.

19. The mechanism according to claim 11, comprising a support body accommodating the components of the mechanism and comprising a lid to be attached onto the support body, wherein the support body and the lid are configured correspondingly to one another so that upon attaching the lid onto the support body, the mechanism is triggered, by a lid attaching sensor configured for sensing attachment of the lid onto the support body, to be switched from the orbital motion mode to the rotary motion mode.

20. The mechanism according to claim 11, further comprising a locking oneway clutch configured for coupling the drive shaft of the orbital motion generator with a stationary housing so as to selectively lock the drive shaft with the stationary housing to a locked stationarily mounted state when the gear element is driven in one direction, or to freewheel in an unlocked movably mounted state of the drive shaft when the gear element is driven in another direction, wherein the one direction equals to the second direction and the other direction equals to the first direction.

21. The mechanism according to claim 20, wherein the stationary housing comprises a lid detachably connectable to and/or pivotably mounted on a spatially fixed support body of the stationary housing, wherein the locking one-way clutch is configured for coupling the drive shaft with the lid.

22. The mechanism according to claim 11, further comprising a locking element configured for selectively locking the drive shaft of the orbital motion generator in a locked stationarily mounted state or for unlocking the drive shaft in an unlocked movably mounted state.

23. The mechanism according to claim 12, wherein the second one-way clutch is arranged to circumferentially surround the first one-way clutch, wherein the first one-way clutch and the second one-way clutch are arranged concentrically around a rotation axis of the mechanism, and wherein the first one-way clutch and the second one-way clutch are arranged in at least overlapping height ranges, in relation to a rotation axis of the mechanism.

24. The mechanism according to claim 11, wherein the one-way clutch arrangement is mounted so as to be immovable along a rotation axis of the mechanism.

25. The mechanism according to claim 12, wherein the gear element comprises a hollow shaft being located between the first one-way clutch and the second one-way clutch so as to circumferentially surround the first one-way clutch and to be circumferentially surrounded by the second one-way clutch.

26. The mechanism according to claim 11, wherein the orbital motion generator comprises the drive shaft having the eccentric section being eccentric with regard to a rotation axis around which the gear element is rotatable driven by the drive unit, wherein the eccentric section extends through the sample holder.

27. The mechanism according to claim 26, wherein the drive shaft has the concentric section being concentric with regard to the rotation axis, wherein at least a part of the concentric section, but not the eccentric section, is surrounded by at least a part of the one-way clutch arrangement.

28. The mechanism according to claim 11, wherein the cooperating cogwheels form part of both the orbital motion generator and the rotary motion generator.

29. The mechanism according to claim 12, wherein the drive shaft is to be coupled to the gear element via the one-way clutch arrangement and forms part of the orbital motion generator, but not of the rotary motion generator.

30. An apparatus for handling a fluidic sample, the apparatus comprising: the mechanism according to claim 1 for generating an orbital motion for mixing the fluidic sample to be accommodated by a sample holder; and the sample holder for accommodating the fluidic sample and being coupled to the mechanism to follow a motion of the second cogwheel.

31. A method of generating an orbital motion for mixing a fluidic sample accommodated by a sample holder, the method comprising: stationarily mounting or locking a first cogwheel having a first through hole and a plurality of first cogs arranged along an outer circumference of the first cogwheel; movably mounting a second cogwheel having a second through hole and a plurality of second cogs arranged along an outer circumference of the second cogwheel; guiding a first concentric section of a drive shaft through a first through hole and guiding a second eccentric section of the drive shaft through the second through hole; mounting a coupling body, which has a plurality of third cogs arranged along an inner circumference of the coupling body, with the first cogwheel and with the second cogwheel to engage part of the first cogs and part of the second cogs by part of the third cogs; and rotating the first section of the drive shaft to thereby generate the orbital motion of the second cogwheel and a sample holder mounted so as to follow a motion of the second cogwheel.

Description

(1) The invention will be described in more detail hereinafter with reference to examples of embodiment but to which the invention is not limited.

(2) FIG. 1 shows a sample handling apparatus according to an exemplary embodiment of the invention for selectively operating a sample holder accommodating fluidic samples in an orbital motion mode for shaking or in a rotary motion mode for centrifuging.

(3) FIG. 2 shows a sample handling apparatus according to another exemplary embodiment of the invention for selectively operating a sample holder accommodating fluidic samples in an orbital motion mode for shaking or in a rotary motion mode for centrifuging.

(4) FIG. 3 illustrates schematically a functioning principle of mechanisms and apparatuses according to exemplary embodiments of the invention providing for an orbital motion mode.

(5) FIG. 4 illustrates part of a sample handling apparatus according to an exemplary embodiment of the invention providing for an orbital motion mode.

(6) FIG. 5 illustrates cooperation between two cogwheels and a toothed belt according to an exemplary embodiment of the invention. It should be mentioned that the cogs of components are not illustrated in FIG. 5.

(7) FIG. 6 to FIG. 9 show plan views and cross-sectional views illustrating cooperation between two cogwheels and a toothed belt in different angular states according to an exemplary embodiment of the invention.

(8) FIG. 10 illustrates a sample handling apparatus according to an exemplary embodiment of the invention in an operation mode in which a lid is attached to cover an interior of a support body.

(9) FIG. 11 shows the sample handling apparatus of FIG. 10 in an operation mode in which the lid is detached.

(10) FIG. 12 shows an internal constitution of the apparatus of FIG. 10, wherein a support body is omitted to expose various internal parts.

(11) FIG. 13 shows a detailed view of the lid of the apparatus of FIG. 10.

(12) FIG. 14 is a cross-sectional view of the apparatus of FIG. 10 showing an internal constitution thereof.

(13) FIG. 15 shows another view of the apparatus of FIG. 10 while the accommodation sections are in an upright position.

(14) FIG. 16 shows another operation mode of the apparatus of FIG. 10, wherein the accommodation sections are in a pivoted position.

(15) FIG. 17 shows a sample handling apparatus according to an exemplary embodiment of the invention in which well plates can be shaken.

(16) FIG. 18 is a cross-sectional view of the apparatus of FIG. 17 illustrating the internal construction thereof.

(17) FIG. 19 is a three-dimensional view of an apparatus according to an exemplary embodiment of the invention with the removed lid.

(18) FIG. 20 shows the apparatus of FIG. 19 in an operation mode in which the accommodation sections are pivoted in response to an applied rotational force.

(19) FIG. 21 shows geometrical conditions in a section of a device according to an exemplary embodiment of the invention in which a rigid or a deformable coupling body interacts with two cogwheels.

(20) FIG. 22 shows a plan view, a three-dimensional view and a detail of a mechanism illustrating an interaction between a coupling body and two cogwheels according to an exemplary embodiment of the invention.

(21) FIG. 23 and FIG. 24 show a sample handling apparatus according to an exemplary embodiment of the invention in which well plates can be shaken.

(22) FIG. 25 shows a three-dimensional view of a sample handling apparatus according to another exemplary embodiment of the invention.

(23) FIG. 26 shows a three dimensional cross-sectional view of the sample handling apparatus of FIG. 25 together with two details illustrating certain features thereof.

(24) FIG. 27 shows a planar cross-sectional view of the sample handling apparatus of FIG. 25 together with two details illustrating certain features thereof.

(25) The illustration in the drawing is schematically. In different drawings, similar or identical elements are provided with the same reference signs.

(26) Exemplary embodiments of the invention allow to operate an apparatus in an operation mode in which an orientation fixed orbital motion is possible. A corresponding embodiment of the invention therefore relates to a mechanism for transferring a rotation motion of a driving motor into an orientation fixed orbital motion which is advantageous for a contamination free mixing of samples in lab containers. In this kind of motion, a shaking shelf board with at least one lab container attached thereto is moved with an angular frequency .sub.1 around a rotational axis of a drive unit. In order to keep the spatial orientation of the lab container constant, the shaking shelf board can additionally be rotated by an angular frequency .sub.2 around an axis which is not identical with an axis of the drive unit but which is parallel to this axis with a distance r0 (eccentricity/orbital radius). In order to maintain this spatial orientation of the shaking shelf board, which is not essential but advantageous, during the rotation, the condition .sub.1=.sub.2 shall be fulfilled.

(27) In contrast to such an orbital motion, centrifugation denotes a sample separation procedure which is based on a different behavior of different molecules in the gravitational field. The gravitational field required for separating such components thereby defines or determines the technical effort for realizing the separation. Therefore, a sufficiently high gravitational force shall be generated artificially. For this purpose, it is possible to rotate the samples within the containers around a certain spatial axis. In the thus generated centrifugal field, the separation procedures are more efficiently and faster as in the gravitational field of the earth, since the required separation forces can be significantly higher. Also a separation of mixtures of fractions of a fluidic sample with very small differences concerning density can be made possible by this procedure.

(28) In biotechnology, centrifugation can be used for separating cells after fermentation, separating of cell fragments after cell exposure, the separation of precipitated or crystallized products from liquids and the separation of liquid systems (extraction). Another application of centrifugation in a biotechnological lab is to collect sample amounts adhering to the surface of the container after execution of tempering or mixture procedures by a centrifugal force in direction of the bottom of the container, for sample collection.

(29) FIG. 1 illustrates a sample handling apparatus 50 according to an exemplary embodiment of the invention.

(30) The apparatus 50 comprises a sample holder constituted by a recessed sample holder plate 14 and tubes or test glasses 40 mounted on the sample holder plate 14. As can be taken from FIG. 1, fluidic samples 38 such as biological liquids are accommodated within the test glasses 40. The apparatus 50 combines two functions in one device, i.e. a shaking function by which the liquid samples 38 are shaken for mixing purposes and a rotary function by which the liquid samples 38 are centrifuged for separating components or fractions thereof.

(31) The sample holder 14, 40 is coupled to a mechanism for switching the sample holder 14, 40 between the orbital motion mode (for shaking) and the rotary motion mode (for centrifuging).

(32) This mechanism comprises a hollow cylindrical shaft 11 as a gear element which can be rotated selectively in a first rotation direction A or in a second rotation direction B around a rotation axis 49. The second rotation direction B is opposite or inverse to the first rotation direction A. The rotation can be powered by a drive engine (not shown in FIG. 1).

(33) Reference numerals 2, 3, 4 and 5 denote components of an orbital motion generator which is configured for generating the orbital motion of the sample holder 14, 40 when the apparatus 50 is operated in the orbital motion mode for mixing in accordance with the first rotation direction A. Furthermore, reference numerals 2, 4 and 5 denote components of a rotary motion generator which is configured to generating a rotary motion of the sample holder 14, 40 when the apparatus 50 is operated in the rotary motion mode in accordance with the second rotation direction B. Reference numerals 12 and 13 denote independently operating components of a one-way clutch arrangement, embodied as a first one-way clutch 12 and a second one-way clutch 13. The skilled person is aware of the fact that a one-way clutch may freewheel in one rotation direction, thereby disabling a force transmission between two connected components, while it enables a force transmission between two connected components in the opposite rotation direction. The two one-way clutches 12, 13 freewheeling in opposite directions are provided for switching between the centrifuging mechanism and the orbital shaking mechanism. Coupling between the two one-way clutches 12, 13 is performed by the hollow shaft 11.

(34) A detail in FIG. 1 shows an example as to how a one-way clutch 12, 13 may be configured. A plurality of circumferentially arranged balls 202 are connected via biasing springs 204 to a central hub 200. The balls 202 are further sandwiched between the hub 200 and an exterior annulus 206. In clockwise direction, rotation of the hub 200 is disabled (for reasons of form closure or force closure), while it is enabled in counterclockwise direction.

(35) As can be taken from FIG. 1, the first one-way clutch 12 is arranged between the hollow shaft 11 and a drive shaft 3. The one-way clutch 12 is configured in such a way that the driving force from the rotated hollow shaft 11 can be transferred to the orbital motion generator 2 to 5 for generating the orbital motion when the hollow shaft 11 is rotated in the first direction A. In other words, the first one-way clutch 12 couples the hollow shaft 11 with the drive shaft 3 when the first motion direction A of the hollow shaft 11 is activated. In contrast to this, the first one-way clutch 12 freewheels when the hollow shaft 11 is rotated in the second direction B. In this operation mode, no force transmission from the hollow shaft 11 to the drive shaft 3 is possible.

(36) The second one-way clutch 13 is configured for coupling the hollow shaft 11 with the rotary motion generator 2, 4, 5, particularly with a first cogwheel 2 of the rotary motion generator 2, 4, 5, to transfer the driving force from the rotating hollow shaft 11 to the rotary motion generator 2, 4, 5 for generating the rotary motion when the hollow shaft 11 is driven in the second direction B. In other words, in this operation mode, force is transmitted from the hollow shaft 11 rotating in direction B via the second one-way clutch 13 to the first cogwheel 2, more precisely to a shaft extension 71 of the first cogwheel 2. In contrast to this, the second one-way clutch 13 freewheels, i.e. does not transmit a force from the rotating hollow shaft 11 to the extension shaft 71 of the first cogwheel 2, when the hollow shaft 11 rotates in the first direction A.

(37) Hence, by simply adjusting the rotation direction of the hollow shaft 11, it is possible for a user to select either the rotary motion mode or the orbital motion mode.

(38) Most specifically, the rotary motion generator 2, 4, 5 comprises the selectively lockable first cogwheel 2. When the mechanism is operated in the rotary motion mode, the first cogwheel 2 is unlocked by correspondingly operating a cogwheel locking element 9. The cogwheel locking element 9 is configured for selectively locking the first cogwheel 2 to a support body 1 (see operation mode shown in FIG. 1) or for unlocking the first cogwheel 2 to assume the unlocked movably mounted state required for the rotary motion mode (in which the cogwheel locking element 9 is not in engagement with the first cogwheel 2, not shown in the figure). In the rotary motion mode, the cogwheel locking element 9 does not protrude into a corresponding recess in the first cogwheel 2. Therefore, the first cogwheel 2 can freely rotate relative to the support body 1 in the rotary motion mode. The first cogwheel 2 is coupled to the hollow shaft 11 via the second one-way clutch 13 and has a plurality of first cogs (see reference numeral 80 in FIG. 6 to FIG. 9) arranged along an outer circumference of the substantially disk-shaped first cogwheel 2.

(39) A second cogwheel 4, also contributing to the rotary motion generator 2, 4, 5, is arranged on top of the first cogwheel 2 and is mounted in a permanently movably way. Hence, the second cogwheel 4 cannot be fastened in the present embodiment, but can freely follow a rotation motion when a corresponding rotation force is exerted to the second cogwheel 4. The second cogwheel 4 also has a plurality of second cogs arranged along an outer circumference of the second cogwheel 4 (see reference numerals 82 in FIG. 6 to FIG. 9).

(40) Furthermore, a toothed belt 5, also contributing to the rotary motion generator 2, 4, 5, is provided as a deformable but non-elongatable coupling body which encloses or surrounds the entire circumference of both the first cogwheel 2 and the second cogwheel 4. The toothed belt 5 has, as can best be taken from reference numeral 84 in FIG. 6 to FIG. 9, a plurality of third cogs arranged along an inner circumference of the toothed belt 5. The toothed belt 5 is mounted with regard to the first cogwheel 2 and with regard to the second cogwheel 4 so as to engage, in each state during the rotation, a corresponding part of the first cogs 80 and a corresponding part of the second cogs 82 by a corresponding part of the third cogs 84.

(41) In this way, the rotary motion of the second cogwheel 4 and of the sample holder 14, 40 (rigidly connected to the second cogwheel 4 by fastening elements such as screws 73) is generated when the hollow shaft 11 is rotated in the second direction B. This transmits force from the hollow shaft 11 via the second one-way clutch 13 to the first cogwheel 2, and from the first cogwheel 2 via the toothed belt 5 to the second cogwheel 4 and from the second cogwheel 4 to the sample holder 14, 40.

(42) For centrifugation by the rotary motion, the locking device 10 connects drive shaft 3 with the support body 1, whereas locking device 9 is not in engagement with the first cogwheel 33. Via a rotary drive (direct drive or transmission by means of gears) a rotation of the hollow shaft 11 in direction B is generated. The introduced torque is transmitted at the exterior diameter of the hollow shaft 11 via the second one-way clutch 13 locking in this direction onto the cogwheel 2. The first one-way clutch 12 does not transmit any torque in this rotation direction B and freewheels. Via the toothed belt 5, the torque is transmitted towards the second cogwheel 4 which is thereby brought into rotation. By means of drive shaft 3, locked by means of locking device 10, a defined alignment of the drive shaft 3 is achieved during centrifugation, on the other hand the equilibration mass or compensation weight 7 fastened to the drive shaft 3 is prevented from rotating (by bearing friction).

(43) The orbital motion generator 2 to 5 is formed by the first cogwheel 2, the second cogwheel 4, the toothed belt 5 and additionally drive shaft 3. For executing the orbital motion mode, the first cogwheel 2 needs to be brought into a locked stationary mounted state as shown in FIG. 1. This is performed by the cogwheel locking element 9, which is embodied as some kind of displaceable pin, which is brought in engagement with a recess in the first cogwheel 2 as shown in FIG. 1 so that the first cogwheel 2 is stationary locked to the support body 1 as a result of the form closure with the cogwheel locking element 9.

(44) As can furthermore be taken from FIG. 1, the first cogwheel 2 has a central first through hole 30. Also the second cogwheel 4 has a central second through hole 32. The above mentioned drive shaft 3 is guided through the first through hole 30 and is guided through the second through hole 32 and is coupled to the hollow shaft 11 via the first one-way clutch 12. The drive shaft 4 is constituted by different sections including a concentric first section 34 and an eccentric second section 36 (eccentricity r0). The first section 34 is guided through the first through hole 30, whereas the second section 36 is guided through the second through hole 32.

(45) The toothed belt 5 is mounted with the first cogwheel 2 and with the second cogwheel 4 so as to engage part of the first cogs 80 and part of the second cogs 82 by part of the third cogs 84 also in the orbital motion mode to thereby generate the orbital motion of the second cogwheel 4 and the sample holder 14, 40 upon rotating the hollow shaft 11 in the first direction A. Again, the sample holder 14, 40 follows motion of the second cogwheel 4 since it is permanently fastened to the second cogwheel 4 by means of the fastening elements, in the shown embodiment the screws 73. This transmits force from the hollow shaft 11 via the first one-way clutch 12 to the drive shaft 3, and from the drive shaft 3 to the second cogwheel 4 and from the second cogwheel 4 to the sample holder 14, 40. The weak coupling between movable cogwheel 4 and fixed cogwheel 2 mediated via toothed belt 5 provides for two superposed rotation motions of the cogwheel 4, i.e. an orbital motion.

(46) In the orbital motion mode, a coupling force resulting from the form closure of the toothed belt 5 with both the first cogwheel 2 and the second cogwheel 4 is larger than a friction force between contacting surfaces of the first cogwheel 2 and the second cogwheel 4. Hence, the toothed belt 5 is mounted with the first cogwheel 2 and with the second cogwheel 4 so as to form a form closure which superposes, to a rotating motion of the second cogwheel 4 transmitted by the drive shaft 3, a rolling motion of the second cogwheel 4 during which the second cogwheel 4 rolls up on the toothed belt 5 limited by a rolling motion during which the toothed belt 5 rolls up on the first cogwheel 2.

(47) FIG. 1 also shows a non-rotationally symmetric compensation weight 7 (for instance shaped as a half disc) which is mounted asymmetrically on the drive shaft 3 and is configured to compensate for a mechanical load acting on the drive shaft 3 upon generating the orbital motion. The equilibration mass or compensation weight 7 is used for balancing out unbalanced masses. The compensation weight 7 is used for the shaking operation mode only, but not for centrifuging, because in the centrifuging mode the opposing sample holder sections automatically balances out the effects of uncompensated weights.

(48) For mixing in the orbital motion mode, the locking device 9 connects cogwheel 2 with the support body 1, whereas locking device 10 is out of engagement with drive shaft 3. Via a rotary drive (direct drive or transmission by means of an additional gear) a rotation of the hollow shaft 11 in direction A is generated. The introduced torque is transmitted at an inner diameter of the hollow shaft 11 via one-way clutch 12 locking in this direction onto the drive shaft 3 with the eccentric section 36, which also rotates in direction A. The second one-way clutch 13 which is fastened to the cogwheel 2 transmits no torque in this direction and freewheels. In view of the toothed belt 5 being always in engagement, an orientation fixed orbital motion results at the shaking shelf board or sample holder 14. By the co-rotating equilibration or compensation weight 7, an unbalanced mass is at least partially compensated.

(49) Thus, by the mere definition of the rotation direction (A or B) of the hollow shaft 11 powered by a not shown drive unit such as an electric motor, the complementary arrangement of the one-way clutches 12 and 13 ensures that at each time either the orbital motion mode or the rotary motion mode is activated. The apparatus 50 provides for a mechanism for generating an orientation fixed orbital movement when the drive shaft 3 is driven. In contrast to this, a centrifugation motion (rotation) can be activated by changing the rotation direction of the hollow shaft 11 by merely inverting the rotation direction of the drive unit powering the hollow shaft 11. Therefore, a single apparatus 50 is sufficient for providing both an orbital motion for shaking the fluidic sample 38 or a rotary motion for centrifuging the fluidic sample 38. Thus, the apparatus 50 provides for both, a gentle mixing of a sensitive biological sample 38 with an orbital motion, and an efficient separation of different fractions of the biological sample 38 by centrifugation. For adjusting a respective operation mode, a user merely has to adjust the rotation direction of the drive unit for driving the hollow shaft 11. The mechanism for generating the shaking motion along an orbital trajectory can be realized by the two cooperating cogwheels 2, 4 driven by drive shaft 3, wherein the cogwheels 2, 4 are weakly coupled by the toothed belt 5. By additionally providing the one-way clutches 12, 13 freewheeling into two opposite directions and therefore also blocking into opposite directions, the shaking function can be integrated in the same apparatus 50 as a centrifugation function. Thus, the operation of two separate devices is avoided and a sample transfer procedure to be performed by a user or an automatic handling device can be omitted.

(50) The actual drive unit (not shown) such as an electric motor can be aligned with the axis of the drive shaft 3. However, it is alternatively possible to arrange the drive unit laterally displaced with regard to the drive shaft 3, for instance by transmitting the drive force of the drive unit via a force transmission belt or the like to the drive shaft 3. Such a lateral geometry may result in a low height of the apparatus 50.

(51) FIG. 1 furthermore shows that an optional shaft locking element 10 can be provided which can also be embodied as a displaceable locking pin which can either be brought, for the rotary motion mode, in engagement with the drive shaft 3 for selective locking of the drive shaft 3 to the support body 1 (as shown in FIG. 1), or which can be brought, for the orbital motion mode, in a non-engaging state for unlocking the drive shaft 3 with respect to the support body 1.

(52) As alternatives to the hollow shaft 11, another gear element such as a cylinder or a pin or shank may be implemented as well.

(53) With regard to the cogwheel system, both cogwheels 2, 4 may have the same number of cogs or teeth. The eccentricity r0 of the drive shaft 3, i.e. the axis distance of shaft section 36 with regard to the rotation axis 49, can be a multiple integer of the distance of adjacent cogs or teeth on the circumferences of the cogwheels 2, 4. Some deviation from an integer value may be possible so as to provide for some clearance as well. The toothed belt 5 with the interior toothing may have a slightly larger inner diameter (for instance larger by about the eccentricity r0) as compared to the outer diameter of each of the cogwheels 2, 4. Then, the desired weak coupling between the two cogwheels 2, 4 can be mediated via the toothed belt 5.

(54) Drive shaft 3 has its eccentric section 36 being eccentric with regard to rotation axis 49 around which the gear element 11 is rotatable when driven by the drive unit 42. The eccentric section 36 extends through recessed sample holder plate 14 of the sample holder 14, 40. The drive shaft 3 further has its concentric section 34 concentric with regard to the rotation axis 49, wherein the concentric section 34, but not the eccentric section 36, is surrounded by the one-way clutches 12, 13. The concentric section 34 forms a bottom part of the drive shaft 3 and the eccentric section 36 forms a top part of the drive shaft 3. The drive shaft 3 bridges and extends over the entire range from the drive unit 42 to the sample holder 14, 40.

(55) FIG. 2 illustrates an apparatus 50 according to another exemplary embodiment of the invention.

(56) In the embodiment of FIG. 2, the two one-way clutches 12, 13 are substituted by bearings 77, 79. Both bearings 77, 79 couple the hollow shaft 11 to the first cogwheel 2 and to the drive shaft 3 so that no force is transmitted via these freewheeling bearings 77, 79. In other words, the bearings 77, 79 freewheel in both opposing directions.

(57) In the shown embodiment, the one-way clutch arrangement is realized by a one-way clutch pin 81 cooperating with the freewheeling bearings 77, 79. As can be taken from a detail shown in FIG. 2, the one-way clutch locking pin 81 can be brought in a first position 83 or in a second position 85. By shifting the pin towards the first position 83, the one-way clutch locking pin 81 rigidly couples the hollow shaft 11 with the first cogwheel 2, while in this operation moment the hollow shaft 11 is continuously freely rotatable relative to the drive shaft 3. In contrast to this, in the operation mode 85, the one-way clutch locking pin 81 has been shifted to the right hand side so that the hollow shaft 11 can freely rotate relative to the first cogwheel 2. In contrast to this, the drive shaft 3 is now rigidly coupled with the hollow shaft 11. In other words, the pin 81 in combination with the bearings 77, 79 freewheeling in both directions provide for the one-way clutch arrangement characteristic.

(58) Furthermore, the optional shaft locking pin 10 is omitted in FIG. 2 but can be foreseen in this embodiment as well. Although not essential, shaft locking pin 10 may be advantageous as well since frictional forces in bearings might otherwise result in a rotation or torsion of the shaft 3. In a low friction or frictionless state, shaft locking pin 10 may be omitted.

(59) FIG. 3 is a schematic illustration of an apparatus 50 according to an exemplary embodiment of the invention.

(60) The mechanism shown in FIG. 3 is constituted by a spatially fixed support body 1, a locked or lockable first cogwheel 2 with a number z.sub.1 of cogs or teeth, and a drive shaft 3 having an eccentric cross-section 36 and a concentric cross-section 34. The concentric cross-section 34 is guided through the first cogwheel 2. Further, a rotatably mounted cogwheel 4 with a number of cogs or teeth z.sub.1 is mounted on the eccentric cross-section 36 of the drive shaft 3. Toothed belt 5 has a number of cogs or teeth z.sub.2>z.sub.1. On the cogwheel 4, any desired shaking shelf board 14 (for instance for lab containers, vials or well plates) can be fastened. Cogwheel 2 is assembled torque proof on the support body 1 (for instance by fixation 6).

(61) Alternatively, it is also possible that the toothing or cogging of the fixed cogwheel 2 is directly integrated in the support body 1. Cogwheel 2 and support body 1 then form a common integral member.

(62) When using a toothed belt 5, its shape always deviates from a circular cross-section (xy in FIG. 5) due to the eccentricity r0. In another embodiment it is also possible that an interior toothed or cogged cogwheel (particularly from plastic material) is used rather than a toothed belt, so that in this scenario it is also possible that the condition x=y applies.

(63) In order to at least partially equilibrate unbalanced masses, it is possible to provide the equilibration mass 7.

(64) As an alternative to the arrangement of toothed belt 5 and cogwheels 2, 4, it is also possible to use two externally toothed and one internally toothed cogwheels, i.e. three cogwheels.

(65) For instance, cogwheel 2 may have z=60 teeth or cogs, and cogwheel 4 may have z=60 teeth or cogs. The toothed belt 5 may for instance have z=62 teeth or cogs. The tooth pitch p may be characterized by p=2 mm, and the eccentricity or the orbital radius r0 may be 2.0 mm (in practice, the value of the eccentricity may vary, for instance may be 1.9 mm or 1.95 mm or 1.85 mm to provide for a slight clearance between the components). For the sake of providing a certain clearance, also for example r0=1.9 mm is possible.

(66) In the scenario FIG. 3, the cogwheel 2 is fixed, and the cogwheel 4 remains orientation fixed during the entire rotation. Toothed belt 5 rotates at each rotation by two teeth or cogs in the rotation direction of the drive shaft 3.

(67) FIG. 4 shows a practical realization of an apparatus 50 according to the schematic illustration of FIG. 3.

(68) FIG. 5 shows a plan view of the cogwheels 2, 4 and of the toothed belt 5 as well as of the drive shaft 3. It should be mentioned that the cogs of components 2, 4, and 5 are not illustrated in FIG. 5.

(69) FIG. 6 to FIG. 9 shows the relative orientation and cooperation of the cogwheels 2, 4 and the toothed belt 5 during an entire rotation. In this illustration, the spatially fixed support body 1 corresponds to the cogwheel 2. The interaction between the cogs 80, 82 and 84 can be retraced based on FIG. 6 to FIG. 9.

(70) In the following, referring to FIG. 10 to FIG. 16, an apparatus 50 according to an exemplary embodiment of the invention will be explained. This apparatus 50 is compact in size and combines an orbital shaker with a centrifuge, for up to four sample containers (for instance Eppendorf Safelock 2.0 mm).

(71) Apparatus 50 comprises the support body 1, a lid 45 and a rotor 89, see FIG. 10 and FIG. 11. The lid 45 is detachably connectable to the support body 1 by pairs of permanent magnets. Advantageously, it is possible to further increase the safety of the user by a mechanical locking element (for instance a bayonet closure). At the support body 1, a turning knob 91 for a user-defined adjustment of the revolution speed of the apparatus 50 is provided. Each of four accommodation sections 90, 92, 94, 96 is capable of accommodating a respective sample container.

(72) In the following, an operation mode of using the apparatus 50 for an orbital motion (mixture of a fluidic sample) will be explained. The lid 45 is detached from the support body 1, see FIG. 11. In an edge of the support body 1, a Hall switch 93 is provided, see FIG. 12. In another edge, a locking device 95 is provided, which is shifted upwardly by a pair of permanent magnets 97. By this mechanism, disk 99 is connected to the support body 1.

(73) The locked disk 99 is fixedly connected (for instance screwed) with the hollow shaft having toothed belt toothing 4, see FIG. 14. A drive engine 42 rotates in one direction. The hollow shaft 11 which is directly connected to the engine shaft has a one-way clutch 12 which transfers a torque onto the drive shaft 3 in this direction. The drive shaft 3 has a concentric cross-section and an eccentric cross-section. The second one-way clutch 13 which is assembled in the hollow shaft 11 freewheels in this direction and does not transfer torque. By the drive shaft 3, cogwheel 4 fastened via a ball bearing on the eccentric cross-section, as well as the equilibration mass 7 are orbitally elongated, wherein the two cogwheels 2, 4 are always connected via toothed belt 5. At the upper cogwheel 4, the rotor 89 is fastened.

(74) For centrifugation, lid 45 is attached to the support body 1, see FIG. 15. One or more permanent magnets 107 integrated in the lid 45 unlock locking device 95 via opposingly (or antiparallel) poled permanent magnets (disk 99 and cogwheel 4 can be rotated with regard to the support body 1), see FIG. 13. Additionally, the equilibration mass 7 and consequently the drive shaft 3 with the eccentric cross-section 36 are connected to the lid 45 and the support body 1 in a torque proof way. As can be seen in FIG. 13 and FIG. 15, a pin 103 protrudes from a top plate 105 of the lid 45 and has an actuator 101 at an end thereof. By means of the actuator 101, a locking of the equilibration mass 7 to the lid 45 may be initiated. Hall switch 93 detects a permanent magnet 107 in the lid 45 and changes the rotation direction of the driving engine 42. Hollow shaft 11 transmits torque via one-way clutch 13 to cogwheel 2. Via the toothed belt 5, the introduced torque is transmitted onto the cogwheel 4 and hence to the rotor 89. One-way clutch 12 freewheels in this direction, i.e. no torque is transmitted to drive shaft 3. Rotor 89 rotates itself and the sample containers therein around its symmetry axis, whereby a centrifugation is started, see FIG. 16.

(75) FIG. 17 shows an apparatus 50 according to another exemplary embodiment of the invention in which the sample holder is realized by a plate 111 having positioning edges 113 in each of the edges of the apparatus 50 for clampingly engaging a well plate (not shown in FIG. 17) carrying various fluidic samples under examination.

(76) FIG. 18 shows a cross-section of the internal constitution of apparatus 50 of FIG. 17. The principles as shown and described above referring to FIG. 1 to FIG. 16 can be implemented here as well.

(77) FIG. 19 and FIG. 20 show a further feature of an apparatus 50 according to an exemplary embodiment of the invention. As can be taken from dashed lines in FIG. 19 and FIG. 20, the (in this case four) accommodation sections 90, 92, 94, 96 are mounted to be pivotable around a pivoting axis (dashed sections) which are perpendicular to a vertical rotation axis of the orbital motion and of the rotary motion so as to be pivoted upon exceeding a predefined rotation force. As shown in FIG. 19, when the rotation of the rotor 89 is slow or the mechanism is in orbital motion mode, the centrifugal force acting on the accommodation sections 90, 92, 94, 96 is small as well. However, upon exceeding a predefined threshold value of the centrifugal force, the accommodation sections 90, 92, 94, 96 will move upwardly as shown in FIG. 20 so that the centrifugation can be performed efficiently. Thus, the accommodation sections 90, 92, 94, 96 are foldable and tilt upon exceeding a certain centrifugal force. Optionally, permanent magnets or other biasing force elements may be provided which tend to keep the accommodation sections 90, 92, 94, 96 in the position of FIG. 19 in orbital motion mode.

(78) The vertical alignment of the accommodation sections 90, 92, 94, 96 may be maintained in the orbital motion mode by permanent magnets or resetting elements. In an embodiment, the accommodation sections 90, 92, 94, 96 do not pivot upon mixing, but only upon centrifuging (with a sufficiently high centrifuging force).

(79) FIG. 21 shows geometrical conditions in a section of a device according to an exemplary embodiment of the invention in which a rigid coupling body 5 (see left hand side) or a deformable coupling body 5 (see right hand side) interacts with two cogwheels 2, 4.

(80) If the coupling body 5 is a rigid structure (such as an internally toothed pinion or gearwheel) the scenario 2100 is obtained.

(81) If the coupling body 5 is a deformable structure (such as a toothed belt) the scenario 2150 is obtained.

(82) The inner diameter D (or more precisely the largest inner extension) of the coupling body 5 is larger, by the eccentricity r.sub.0, than twice of the radius r.sub.1 of the cogwheels 2, 4:
D=r.sub.1+r.sub.1+r.sub.0=d.sub.1+r.sub.0

(83) FIG. 22 shows a plan view 2200, a three-dimensional view 2230 and a detail 2260 of a mechanism illustrating an interaction between coupling body 5 and two cogwheels 2, 4 according to an exemplary embodiment of the invention.

(84) For a proper orbital motion, the following conditions should be fulfilled:

(85) a) Inner diameter D (in case of a rigid coupling body 5) or largest extension (in case of a deformable coupling body 5) of the coupling body 5 should ideally be the sum of the outer diameter of one of the cogwheels 2, 4 (d.sub.1=r.sub.1+r.sub.1) plus the eccentricity r.sub.0, i.e. D=r.sub.1+r.sub.1+r.sub.0=d.sub.1+r.sub.0.

(86) b) The number z.sub.2 of teeth of the coupling body 5 should be larger, by at least one tooth, than the number z.sub.1 of teeth of the cogwheels 2, 4: z.sub.2z.sub.1+1

(87) c) The eccentricity r.sub.0 should be larger than the height h of the teeth (in order to enable a decoupling of the teeth from the coupling body 5): r.sub.0>h

(88) d) The eccentricity r.sub.0 should be selected so that the number z.sub.2 of teeth of the coupling body 5 is integer (plus some clearance, as the skilled person will understand): r.sub.0=(Lz.sub.1*p)/2, wherein L=z.sub.2*p is the circumferential length of the coupling body 5 and p is the tooth pitch.

(89) FIG. 23 shows a plan view and FIG. 24 shows detailed views of a sample handling apparatus 2300 according to an exemplary embodiment of the invention in which well plates (not shown) can be shaken.

(90) The functionality of the sample handling apparatus 2300 equals to that of the embodiment of FIG. 17, i.e. it is an orbital shaker with a flat construction for handling well plates. The shown embodiment has implemented the function shaking by orbital motion. In contrast to the embodiment of FIG. 17, the embodiment of FIG. 23 has a direct driving mechanism for drive shaft 3, wherein FIG. 17 and FIG. 18 implement an indirect drive. Additionally, the positioning edges 113 have an edge locking mechanism (of the type as disclosed in WO 2011/113858). In this embodiment, a compensation weight 7 (not shown) can be advantageously attached on drive shaft 3.

(91) FIG. 25 shows a three-dimensional view of a sample handling apparatus 50 according to another exemplary embodiment of the invention. Construction of the sample handling apparatus 50 is similar to FIG. 10. The sample handling apparatus 50 has a support body 1 and a removable lid 45. However, the lid has a recess in a top surface thereof which is selectively closable openable by moving a slidable plate 2502. In the shown configuration, plate 2502 covers the recess in lid 45 so that the lid 45 is in a closed state. By operating an actuation pin 2504 along a rotation trajectory 2506, the plate 2502 is slid below the outer surface of the lid 45, thereby exposing an interior of the sample handling apparatus 50 to an external environment. This also allows to handle sample containers in accommodation sections 90, 92, 94, 96.

(92) FIG. 26 shows a three dimensional cross-sectional view of the sample handling apparatus 50 of FIG. 25 together with two details 2620, 2640 illustrating certain features thereof. FIG. 27 shows a corresponding planar cross-sectional view of the sample handling apparatus 50 together with two details 2720, 2740 illustrating certain features thereof.

(93) In the following, reference is made to the differences of the embodiment of FIG. 26 and FIG. 27 as compared to the embodiments described above. In the embodiment of FIG. 26 and FIG. 27, a shaft locking element 10 is omitted. In contrast to this, the sample handling apparatus 50 further comprises a locking one-way clutch 2602 configured for coupling drive shaft 3 of the orbital motion generator 2 to 5 with lid 45 on support body 1 so as to selectively lock the drive shaft 3 with the lid 45 on the support body 1 to a locked stationarily mounted state when the gear element 11 is driven in direction B (compare FIG. 1), or to freewheel in an unlocked movably mounted state of the drive shaft 3 when the gear element 11 is driven in the other direction A.

(94) As in the above embodiments, the second one-way clutch 13 is arranged to circumferentially surround the first one-way clutch 12. The first one-way clutch 12 and the second one-way clutch 13 are arranged concentrically around a rotation axis of drive shaft 3 of the orbital motion generator 2 to 5. The first one-way clutch 12 and the second one-way clutch 13 are arranged at overlapping height ranges in relation to the rotation axis of the drive shaft 3 of the orbital motion generator 2 to 5. As in the previously described embodiments, the gear element 11 comprises a hollow shaft being located between the first one-way clutch 12 and the second one-way clutch 13 so as to surround the first one-way clutch 12 and to be surrounded by the second one-way clutch 13.

(95) Also in FIG. 25 to FIG. 27, the mechanism comprises cooperating cogwheels 2, 4 forming part of both the orbital motion generator 2 to 5 and the rotary motion generator 2, 4, 5. Drive shaft 3 which is to be coupled to the gear element 11 via the one-way clutch 12 forms part of the orbital motion generator 2 to 5, but not of the rotary motion generator 2, 4, 5.

(96) In contrast to the previously described embodiments, the FIG. 26 and FIG. 27 embodiment omits shaft locking element and implements instead of this a third one-way clutch, i.e. locking one-way clutch 2602. The outer ring of the locking one-way clutch 2602 is connected to the stator housing (here lid 45, alternatively support body 1) of the sample handling apparatus 50 in a rotatably fixed or torque-proof way. Clamping elements of the locking one-way clutch 2602 run on drive shaft 3. By the locking one-way clutch 2602, rotation of the drive shaft 3 is disabled in one direction and is enabled in the opposite direction. In order to enable the locking one-way clutch 2602 to fulfil the function of the shaft locking element 10, locking one-way clutch 2602 freewheels in the same direction as the second one-way clutch 13 and freewheels in the opposite direction than the first one-way clutch 12. An advantage of the shown embodiment in contrast to the provision of shaft locking element 10 is that an automatic (i.e. without the need of an active control) locking and unlocking of the drive shaft 3 with regard to the stator housing is made possible with simple means.

(97) It should be noted that the term comprising does not exclude other elements or features and the a or an does not exclude a plurality. Also elements described in association with different embodiments may be combined.

(98) It should also be noted that reference signs in the claims shall not be construed as limiting the scope of the claims.