GB2498953A

GB2498953A - Mechanism for orbital shaking motion

Info

Publication number: GB2498953A
Application number: GB1201632.5A
Authority: GB
Inventors: Andreas Vester
Original assignee: Quantifoil Instruments GmbH
Current assignee: Quantifoil Instruments GmbH
Priority date: 2012-01-31
Filing date: 2012-01-31
Publication date: 2013-08-07
Also published as: GB201201632D0

Abstract

Mechanism for orbital shaking motion for mixing a fluidic sample 38 in sample holder 14, 40, comprises a stationary or lockable first cogwheel 2 with first hole 30 and a plurality of first cogs 80 on an outer circumference, a movably second cogwheel 4 with second hole 32 and a plurality of second cogs 82 on an outer circumference, a drive shaft 3 with concentric first section 34 and eccentric second section 36, wherein the first section 34 passes through first hole and second section passes through second hole, and a coupling body 5 with a plurality of third cogs 84 on an inner circumference, wherein the coupling body is mounted with the first and second cogwheels such that the third cogs engage with part of the first cogs and second cogs wherein with the first cog locked, rotation of the drive shaft generates orbital shaking or oscillation motion of the second cogwheel and sample holder. The mechanism may comprise hollow shaft 11, clutches 12, 13 and first cog locking mechanism 19. Rotation of hollow shaft in direction A actives clutch 12 resulting in orbital shaking motion. Unlocking of first cog and rotation of hollow shaft in direction B actives clutch 13 resulting in rotation motion for centrifuging samples.

Description

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Cog-based mechanism for generating an orbital shaking motion

The invention relates to a mechanism for generating an orbital motion 5 for mixing, particularly for shaking, a fluidic sample to be accommodated by a sample holder.

Moreover, the invention relates to an apparatus for handling a fluidic sample.

Beyond this, the invention relates to a method of generating an orbital 10 motion for mixing, particularly for shaking, a fluidic sample accommodated by a sample holder.

US 2010/218620 of the same applicant Quantifoil Instruments discloses a sample handling device for handling a sample, the sample handling device 15 comprising a drive shaft being drivable by a drive unit, a base plate mounted to follow a motion of the drive shaft when being driven by the drive unit, wherein the base plate is configured to receive a sample carrier block mountable to follow a motion of the base plate, and a compensation weight mounted asymmetrically on the drive shaft in a manner to at least partially 20 compensate an unbalanced mass of the sample handling device during the motion.

JP 10277434 discloses a single apparatus to shake, agitate and centrifuge a sample in a tube by providing a shaker for sample mixing, particularly for shaking, a centrifugal tube (sample tube) in the center of a 25 rotor. A shaker shaft is eccentrically fixed to the upper part of a rotor shaft connected to the shaft of a DC motor with an eccentric distance to constitute a shaker. The shaker shaft is freely rotatable through a ball bearing, the upper end is firmly held to a disk, and the upper face of the disk is adhered to the lower face of an oscillator pad. When the motor shaft and rotor shaft are 30 rotated, the shaker shaft is eccentrically rotated with the eccentric distance. Since the shaker is provided in the center of a small-sized centrifuge and integrally housed therein in this way, the sample in a tube is shaken, agitated and centrifuged with only one device, and the device setting space is reduced.

However, efficiently generating an orbital motion may still be a

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challenge.

It is an object of the invention to efficiently generate an orbital motion for handling of fluidic samples.

5 In order to achieve the object defined above, the subject-matter accord ing to the independent claims is provided. Further embodiments are shown by the dependent claims.

According to an exemplary embodiment of the invention, a mechanism (or device) for generating an orbital motion for sample mixing, particularly for 10 shaking, a fluidic sample accommodated by a sample holder is provided, wherein the mechanism comprises 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 15 arranged along an outer circumference of the second cogwheel, and a drive shaft having a concentric first section and an eccentric second section. The first section is guided through the first through hole and the second section is guided through the second through hole. A coupling body having a plurality of third cogs arranged along an inner circumference of the coupling body is 20 provided, 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 to follow a motion of the second cogwheel upon rotating the first section of the drive shaft. 25 According to another exemplary embodiment of the invention, an apparatus for handling a fluidic sample is provided, wherein the apparatus comprises a mechanism having the above mentioned features for generating an orbital motion for mixing, particularly for shaking, the fluidic sample to be accommodated by a sample holder, and comprising the sample holder for 30 accommodating the fluidic sample and being coupled to the mechanism to follow a motion of the second cogwheel.

According to still another exemplary embodiment of the invention, a method of generating an orbital motion for mixing, particularly for shaking, a fluidic sample accommodated by a sample holder is provided, wherein the

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method comprises 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 5 outer circumference of the second cogwheel, and 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. The method further comprises mounting a coupling body, which has a plurality of third cogs arranged along an inner circumference of the coupling body, with 10 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 to follow a motion of the second cogwheel.

15 According to still another exemplary embodiment of the invention, a program element (for instance a software routine, in source code or in executable code) is provided, which, when being executed by a processor (such as a microprocessor or a CPU), is adapted to control or carry out a method having the above mentioned features.

20 According to yet another exemplary embodiment of the invention, a computer-readable medium (for instance a CD, a DVD, a USB stick, a floppy disk or a harddisk) is provided, in which a computer program is stored which, when being executed by a processor (such as a microprocessor or a CPU), is adapted to control or carry out a method having the above mentioned 25 features.

Orbital motion generation control which may be performed according to embodiments of the invention can be realized by a computer program, that is by software, or by using one or more special electronic optimization circuits, that is in hardware, or in hybrid form, that is by means of software 30 components and hardware components.

In the context of this application, the term "sample holder" may particularly denote any physical structure delimiting a sample accommodation volume and hence being configured for holding a fluidic sample or a fluidic sample container.

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In the context of this application, the term "fluidic sample" may particularly denote a sample comprising a fluid, i.e. a liquid and/or gaseous medium, optionally comprising solid particles as well. Examples for fluidic samples are chemical or biochemical solutions which may comprise, for 5 instance, one or more fractions of cells, proteins, genes, etc.

In the context of this application, the term "orbital motion", particularly orientation-fixed orbital motion, may particularly denote a motion along a trajectory which is obtained when a structure is rotating with a first angular frequency around a first central rotation axis with a superposed additional 10 rotation with a second angular frequency around a second rotation axis, which may be parallel to the first rotation axis. The second angular frequency may have an opposite sign and may have the same absolute value as the first angular frequency.

In the context of this application, the term "shaking" may particularly 15 denote a treatment of the fluidic sample for mixing components thereof. Shaking may be performed in a contamination-free and gentle manner by exposing the fluidic sample to an acceleration triggered by orbital motion.

In the context of this application, the term "stationary mounted" may particularly denote that the corresponding cogwheel is permanently fixed or 20 immobilized (for instance integrally formed) with a support structure or may be in an operation mode in which a lockable cogwheel is in fact locked. The term "lockable" may particularly denote that the corresponding cogwheel can be selectively unlocked to move or locked to be fixed (for instance with regard to a support structure).

25 In the context of this application, the term "cogs" may particularly denote physical structures such as rips, teeth or any other kind of protrusions of a physical body which are arranged in a sequence for being subsequently (and optionally partially simultaneously) engaged by corresponding cooperating grooves or indentation of another cooperating physical body for 30 providing a force coupling between the physical bodies.

In the context of this application, the term "concentric shaft section" may particularly denote a portion of a shaft in length direction which portion has a length axis being aligned to or identical to the rotation axis.

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In the context of this application, the term "eccentric shaft section" may particularly denote a portion of a shaft in length direction which portion has a length axis being parallel shifted or laterally spaced or displaced with regard to the rotation axis.

5 According to an exemplary embodiment of the invention, a cog-based mechanism for generating an orientation-fixed orbital shaking motion is provided. Particularly, two cogwheels with exterior cog sequences are surrounded - with a distance exceeding a mere clearance - by a coupling body having a correspondingly configured interior cog sequence. Upon rotating the 10 eccentrically mounted upper cogwheel which may be rigidly connected to a sample holder, the weak coupling between the spatially fixed lower cogwheel and the movably mounted upper cogwheel imparted by the coupling body overlays a further rolling motion to the rotating motion of the upper cogwheel, thereby generating in total an orbital motion of the upper cogwheel and hence 15 of the sample holder with high accuracy and low effort.

In the following, further exemplary embodiments of the mechanism will be explained. However, these embodiments also apply to the apparatus, the method, the computer-readable medium and the program element. 20 In an embodiment, the orbital motion generator and the rotary motion generator may be at least partially constituted by the same components (such as three cogwheels which contribute to the orbital motion generation as well as to the rotary motion generation). In this embodiment, the orbital motion generator and the rotary motion generator may at the same time be at least 25 partially constituted by different components (such as a drive shaft which contributes only to the orbital motion generation, but not to the rotary motion generation).

In an embodiment, each of the first cogwheel and the second cogwheel is a toothed belt disc and the coupling body is a toothed belt. Such a toothed 30 belt disk may be a disk-shaped or cylindrical body having a curved surface which includes a circumferential arrangement of rips. Correspondingly, the coupling body may be a belt, i.e. made of a flexible material and having indentations which have a shape corresponding to the rips of the first and

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second cogwheels. Hence, engagement between the rips and the indentations is possible to provide for a form closure based force transmission.

In an embodiment, each of the first cogwheel and the second cogwheel is a sprocket and the coupling body is a sprocket chain. Therefore, several 5 alternatives to a toothed belt configuration of the cogwheels are possible. For instance, a regular arrangement of indentations in a sprocket chain may cooperate with a corresponding arrangement of protrusions in a circumferential surface of a sprocket for force transmission.

In an embodiment, the coupling body is a flexible structure being 10 deformable but non-elongatable (it may also be basically non-elongatable, i.e. a slight elongation might be possible in view of a slight flexibility of the material of the coupling body) 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. The term "deformable 15 but non-elongatable" may denote a characteristic according to which the shape of the coupling body may be changed by applying a deforming force, but that the entire length along a circumference of the coupling body may remain constant or basically constant upon applying a deforming force. Hence, the coupling body may have an inelastic behavior. By manufacturing the coupling 20 body as a slightly flexible, but non-expandable structure, a weak coupling between the two cogwheels is enabled which provides for the necessary force transmission to generate an orbital motion. The coupling body may for instance be an annular structure made of a bendable material such as rubber covered by a non-expandable fabric or web so as to show, as a whole, the 25 described properties.

In an alternative embodiment, 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. In contrast to the previously 30 described embodiment, the coupling body can also be configured as an undeformable solid body (for example made of plastic), for instance a ring with an internal toothing.

In an embodiment, the coupling body is a closed annular structure, particularly a structure being quasi-rotationally symmetric in a force-free state.

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Such a ring-like structure may be basically rotationally symmetric with the particularity that the internal toothing provides for a slight deviation as compared to a completely rotationally symmetric arrangement.

In an embodiment, the coupling body is an annular structure having an 5 inner diameter which is larger than an outer diameter of the first cogwheel and the second cogwheel, particularly about one times of an eccentricity of the second section of the drive shaft larger. The largest inner extension of the coupling body may be larger, by the eccentricity, than the diameter of one of the cogwheels. The term "eccentricity" may denote a spatial, lateral shift of 10 the eccentric portion (more particularly of a center of gravity thereof) as compared to the concentric portion (more particularly of a center of gravity thereof) and the rotation axis of the shaft.

In an embodiment, the mechanism comprises a support body on which the second cogwheel, the drive shaft and the coupling body are mounted 15 (however, one or more of these components, particularly the coupling body, may be mounted so as to be still able to move relative to the support body), wherein the first cogwheel is configured as an integral portion of the support body. The support body may form a base of the apparatus. Since the first cogwheel may be stationarily mounted, it may be formed as part of the 20 support body or housing of the device, thereby allowing for a compact construction being manufacturable with reasonable effort.

In an embodiment, a number of the first cogs is the same as a number of the second cogs. In this case a smooth and low friction rolling of the two cogwheels on one another, coupled by the coupling element, can be obtained. 25 In an embodiment, the number of the first cogs and the number of the second cogs is smaller than a number of the third cogs. If the number of third cogs is larger than the number of the first cogs and the number of the second cogs, it can be ensured that in each operation mode only a portion of the first and second cogs is contacted by the third cogs, thereby promoting the desired 30 orbital motion.

In an embodiment, in the orbital motion mode, a coupling force resulting from the form closure of the coupling body with both the first cogwheel and the second cogwheel is larger than a friction force (for instance a bearing force or bearing load in bearings of the device) between the first

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cogwheel and the second cogwheel. The form closure is generated by an engagement of the cogs of the cogwheels between cogs of the coupling body. The friction force between the cogwheels has the tendency to prevent relative motion between the cogwheels, while the coupling force triggers such a 5 motion. By configuring the bearings, materials, surface roughness, driving force, etc., correspondingly, the requirement of a coupling force exceeding the friction force can be met.

In an embodiment, in the orbital motion mode, the coupling body is mounted with the first cogwheel and with the second cogwheel so as to form a 10 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. The two overlaid rotations of the second cogwheel with two parallel rotation axes allows 15 for the generation of the orbital motion. This particularly holds when the two rotational frequencies have the same absolute values but opposite signs.

In an embodiment, the mechanism comprises a drive unit, particularly an electric motor, being configured for moving, particularly rotating, the gear element. However, it is also possible that the drive unit is a handle or the like 20 which is operable by a user so as to initiate rotation by muscle force.

In an embodiment, the mechanism comprises 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. By providing a compensation weight which is 25 mounted asymmetrically on the drive shaft (for instance shaped as a half disk) it is possible to compensate for unbalanced forces acting around the circumference of the drift shaft in the orbital motion mode. Therefore, by providing such a compensation weight, wear of the mechanism may be efficiently suppressed. The system may also comprise a mechanism for 30 spatially fixing the compensation weight upon switching from the orbital motion mode to the rotary motion mode. Such a mechanism may be realized as a pin on a lid for covering a support body, wherein covering the support body with the lid may press the pin against the compensation weight thereby preventing motion of the compensation weight in the centrifuging mode.

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In an embodiment, the mechanism is configured for switching the sample holder accommodating the fluidic sample between an orbital motion mode for sample mixing, particularly for shaking, in which the orbital motion is performed, and a rotary motion mode for sample separation, particularly for 5 centrifuging, 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 comprises a gear element being drivable by a drive unit to move, 10 particularly to rotate, selectively in a first direction or in a second direction being inverse to the first direction, and a rotary motion generator configured for generating a rotary motion of the sample holder when being operated in the rotary motion mode. A one-way clutch arrangement may be provided and configured for selectively coupling the gear element with the orbital motion 15 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 (i.e. the corresponding functional part of the one-way clutch arrangement may freewheel without transmitting a force when the gear 20 element is driven in the second direction). The one-way clutch arrangement may be further configured for, in an alternative operation mode, selectively 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 25 direction and to freewheel when the gear element is driven in the first direction (i.e. the corresponding other functional part of the one-way clutch arrangement may freewheel without transmitting a force when the gear element is driven in the first direction). In the context of this application, the term "rotary motion" may particularly denote a motion along a trajectory 30 which is obtained when a structure is rotating with a certain angular frequency around one rotation axis. In the context of this application, the term "centrifuging" may particularly denote a treatment of the fluidic sample for separating components thereof into different fractions. Centrifuging may be performed in an efficient manner by rotating the fluidic sample, thereby

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separating components thereof due to different behavior of different fraction upon exerting a centrifugal force. In the context of this application, the term "gear element" may particularly denote a physical structure capable of transmitting a force between two members which are mechanically coupled by 5 the gear element. Such a gear element may be a hollow shaft coupling a first member accommodated within the hollow shaft with a second member accommodated around the hollow shaft. Alternatively, such a gear element may be a reciprocating element coupling a member coupled to one section of the reciprocating element with another member coupled to another section of 10 the reciprocating element, etc. In the context of this application, the term "one-way clutch" may particularly denote a clutch, i.e. a force coupling element, which transmits a drive force between two connected members in one motion direction (for instance in one rotation direction such as a clockwise rotation) but which inhibits or disables transmission of a drive force in another, 15 particularly opposite, direction (for instance in an inverse rotation direction such as a counterclockwise rotation).

According to such an embodiment, a mechanism is provided for activating either an orbital motion mode (particularly an orientation-fixed orbital shaking motion) or a rotary motion mode (particularly a centrifuging motion) merely by 20 inversing a drive direction of a drive unit which only provides the drive power. Particularly, a one-way clutch arrangement couples a gear element selectively to an orbital motion generator assembly for generating an orbital motion or to a rotary motion generator assembly for generating a rotary motion of a sample holder accommodating a sample. When the one-way clutch arrangement 25 couples the gear element to one of the orbital motion generator or the rotary motion generator for force transmission, the respectively other motion generator is deactivated by a freewheeling of the one-way clutch arrangement in this coupling direction. The selection whether the orbital motion mode or the rotary motion mode shall be activated can be made merely by selecting a 30 rotation direction of a drive unit such as an electric engine. Therefore, an easily operable dual-mode system is provided allowing to flexibly switch between an orbital mixing mode of the fluidic sample and a centrifuging mode of the fluidic sample merely by changing a rotation direction of the gear element. Hence, both functions may be integrated in a single device.

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In an embodiment, 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 5 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 (being a separate physical structure than the first 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 10 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. Hence, it is possible to constitute the one-way clutch arrangement from two different one-way clutches - one coupling a first section of the gear element with the orbital motion generator and the other one coupling a second 15 section of the gear element with the rotary motion generator. In this scenario, always only one of the two one-way clutches is active for force transmission and the respective other one is inactive or freewheels. This provides a mechanism which allows to select the motion mode merely by adjusting the rotation direction of the gear element.

20 However, as an alternative to two separate one-way clutches, the one way clutch arrangement may for instance be also realized by a shiftable locking pin (or any other kind of locking element) in combination with two freewheeling bearings between the gear element on the one hand and the orbital motion generator and the rotary motion generator, respectively, on the 25 other hand. By engaging the locking pin between gear element and orbital motion generator, these two components may be rigidly coupled so that an orbital motion mode is selected. At the same time, the locking pin has no influence on the freewheeling bearing between the gear element and the rotary motion generator so that the rotary motion mode is deactivated in this 30 configuration. Upon shifting the locking pin to another position in which it rigidly couples the gear element with the rotary motion generator while allowing the orbital motion generator to freewheel relative to the gear element by the freewheeling bearing, the rotary motion mode may be selected. The

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skilled person will understand that other alternatives for realizing the function of the one-way clutch arrangement are possible.

In an embodiment, the first one-way clutch and the second one-way clutch freewheel in opposite directions and lock in opposite directions. For 5 instance, the first one-way clutch may freewheel in a clockwise rotation direction while locking in a counterclockwise rotation direction, or vice versa. The second one-way clutch may then freewheel in the counterclockwise rotation direction while locking in the clockwise rotation direction, or vice versa. Therefore, by selecting a rotation direction of the gear element, it is 10 selectable which one of the one-way clutches locks and which one freewheels.

In an embodiment, the gear element is configured as a hollow shaft. Such a hollow shaft, which may have a tubular or hollow cylindrical geometry, may be directly coupled to a drive unit for providing the driving force or power, such as an electric motor.

15 In an embodiment, the first one-way clutch is arranged between an interior surface of the hollow shaft and an exterior surface of a drive shaft of the orbital motion generator. The second one-way clutch may be arranged between an exterior surface of the hollow shaft and an interior surface of a movably mounted cogwheel (or a tubular cogwheel extension shaft thereof) of 20 the rotary motion generator. Thus, an outer surface of the hollow cylindrical shaft may be coupled for transmitting rotary motion force, while an inner surface of the cylindrical hollow shaft may be coupled for transmitting orbital motion force. However, the arrangement may be also vice versa.

In an embodiment, the rotary motion generator comprises the second 25 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, 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 30 the rotary motion of the second cogwheel and a sample holder to be mounted to follow a motion of the second cogwheel upon rotating the gear element in the second direction. Upon activating the rotary motion mode, the gear element may transmit a driving force to the movably configured first cogwheel which, via the coupling body, also drives the second cogwheel which in turn

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rotates the sample holder for centrifugation.

In an embodiment, the mechanism further comprises 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 5 movably mounted state. Such a cogwheel locking element may be a locking pin which can be spatially shifted so as to trigger a rigid coupling between the first cogwheel and a support body or the like, or for decoupling these two elements from one another by disengaging the locking pin from the first cogwheel.

10 In an embodiment, the mechanism further comprises 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. Also the shaft locking element may be embodied as a shiftable pin which selectably allows to lock the drive shaft to a support body 15 or the like, or to decouple these two components from one another.

In an embodiment, the mechanism comprises a support body accommodating a part or all of the components of the mechanism and comprises a lid to be attached onto the support body, wherein the support body and the lid are configured to correspond to one another so that upon 20 attaching the lid onto the support body, the mechanism is triggered to be switched from the orbital motion mode to the rotary motion mode. Particularly, a lid attaching sensor may be provided at the lid and/or at the support body which may be configured for sensing attachment of the lid onto the support body and/or detachment of the lid from the support body. Such a provision 25 acts as a safety feature while at the same time allowing a user to easily adjust the rotary motion mode or the orbital motion mode. In this embodiment, when the support body is uncovered (i.e. the lid is detached), the orbital motion or shaking mode is activated. Upon attaching the lid to the support body, a switch may be actuated (for instance based on a sensor signal) which changes 30 rotation direction of the gear element. Merely by taking this measure, the motion mode is changed from the orbital motion mode to the rotary motion mode. Since centrifuging in the rotary motion mode involves in many cases significantly larger rotational forces and hence an increased risk in a lab,

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activating the centrifuging only upon putting the lid on the support body also increases the safety for a user.

In the following, further exemplary embodiments of the apparatus will 5 be explained. However, these embodiments also apply to the mechanism, the method, the computer-readable medium and the program element.

In an embodiment, the sample holder comprises one or more accommodation sections each having an accommodation recess each configured for receiving a container including one or more fluidic samples. In 10 one embodiment, exactly one fluidic sample is treated by the apparatus. Such a sample may be accommodated within a vial or any other container. It is however also possible that an arrangement of multiple fluidic samples is treated for mixing and/or centrifuging in the same apparatus at the same time. For instance, a circumferential arrangement of accommodation recesses 15 and corresponding samples may be provided. Alternatively, it is also possible that for instance two dimensional arrays of samples are treated by the apparatus such as well plates or the like. For instance, a 96 well plate sample holder may be used in conjunction with the apparatus. With regard to suitable sample holders, it is possible to have four tubes, four well plates, any other 20 number of tubes or well plates, common or separate structures for accommodating them, multiple samples, etc.

In an embodiment, each of the one or more accommodation sections is mounted to be pivotable around a pivoting axis being perpendicular to a rotation axis of the orbital motion and the rotary motion so as to be pivoted 25 only upon exceeding a predefined rotation force. By mounting the accommodation sections to be pivotable allows to increase the centrifuging efficiency while rotating the sample holders.

It is also possible to operate the apparatus in combination with an automatic sample transfer system. For example, it is possible to pipette fluidic 30 samples into sample containers of the apparatus. It is also possible to provide a temperature adjustment unit within the apparatus, for instance to perform PCR (Polymerase Chain Reaction) with the fluidic samples. It is also possible that the apparatus itself includes detector components such as an optical detector for detecting separated components of the sample. Alternatively, it is

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possible to move the apparatus into a separate detection system. For instance, a robot driven gripper arm may grip the apparatus and may transfer the apparatus towards a detector position.

It is possible that the samples are cooled (for instance by injecting an 5 air stream into the interior accommodation space of the apparatus) or heated during centrifuging and/or during mixing.

Merely as examples, apparatuses according to exemplary embodiments of the invention may be realized as one or more of the following: an orbital shaker for lab containers; an orbital shaker for well plates with a flat 10 construction and a high mixing frequency; a combination of an orbital shaker and a centrifuge for lab containers (also well plates); a combination of orbital shaker, centrifuge and a homogenizer (such a function may be implemented, for instance by a linear motion of a rotor, for instance reciprocating upwardly and downwardly); integration of an automatic container locking (for instance 15 an edge locking mechanism); an integration of a sample supply and/or sample remove unit or a pipette device; integration of an evaluation device (for instance an optical detector); integration of a precise positioning unit for positioning fluidic sample containers (for example, the containers may be pivoted at defined points in order to provide for a sample supply or an 20 evaluation here); integration of a temperature adjustment unit; etc.

The aspects defined above and further aspects of the invention are apparent from the examples of embodiment to be described hereinafter and are explained with reference to these examples of embodiment.

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

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 30 rotary motion mode for centrifuging.

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.

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

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

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.

Fig. 6 to Fig. 9 show plan views and cross-sectional views illustrating 10 cooperation between two cogwheels and a toothed belt in different angular states according to an exemplary embodiment of the invention.

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.

15 Fig. 11 shows the sample handling apparatus of Fig. 10 in an operation mode in which the lid is detached.

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

Fig. 13 shows a detailed view of the lid of the apparatus of Fig. 10. 20 Fig. 14 is a cross-sectional view of the apparatus of Fig. 10 showing an internal constitution thereof.

Fig. 15 shows another view of the apparatus of Fig. 10 while the accommodation sections are in an upright position.

Fig. 16 shows another operation mode of the apparatus of Fig. 10, 25 wherein the accommodation sections are in a pivoted position.

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

Fig. 18 is a cross-sectional view of the apparatus of Fig. 17 illustrating the internal construction thereof.

30 Fig. 19 is a three-dimensional view of an apparatus according to an exemplary embodiment of the invention with the removed lid.

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.

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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.

Fig. 22 shows a plan view, a three-dimensional view and a detail of a 5 mechanism illustrating an interaction between a coupling body and two cogwheels according to an exemplary embodiment of the invention.

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.

10 The illustration in the drawing is schematically. In different drawings,

similar or identical elements are provided with the same reference signs.

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 15 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 coi around a rotational axis of a drive unit. In order to keep the spatial 20 orientation of the lab container constant, the shaking shelf board can additionally be rotated by an angular frequency co2 around an axis which is not identical with an axis of the drive unit but which is parallel to this axis with a distance rO (eccentricity/orbital radius). In order to maintain this spatial orientation of the shaking shelf board, which is not essential but 25 advantageous, during the rotation, the condition -coi=co2 shall be fulfilled.

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 30 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

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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.

In biotechnology, centrifugation can be used for separating cells after 5 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 10 force in direction of the bottom of the container, for sample collection.

Fig. 1 illustrates a sample handling apparatus 50 according to an exemplary embodiment of the invention.

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 15 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 20 fractions thereof.

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).

This mechanism comprises a hollow cylindrical shaft 11 as a gear 25 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).

Reference numerals 2, 3, 4 and 5 denote components of an orbital 30 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

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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 5 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 10 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.

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 15 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.

As can be taken from Fig. 1, the first one-way clutch 12 is arranged 20 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 25 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.

The second one-way clutch 13 is configured for coupling the hollow shaft 30 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

- 20 -

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 5 the first cogwheel 2, when the hollow shaft 11 rotates in the first direction A.

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.

Most specifically, the rotary motion generator 2, 4, 5 comprises the 10 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 15 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 20 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.

A second cogwheel 4, also contributing to the rotary motion generator 2, 25 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 30 circumference of the second cogwheel 4 (see reference numerals 82 in Fig. 6 to Fig. 9).

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

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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 5 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.

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 10 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.

15 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 20 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 25 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).

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 30 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

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to the support body 1 as a result of the form closure with the cogwheel locking element 9.

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 5 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 rO). The first section 34 is guided 10 through the first through hole 30, whereas the second section 36 is guided through the second through hole 32.

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 15 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 20 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. 25 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 30 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 ro 11 s up on the first cogwheel 2.

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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 5 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.

For mixing in the orbital motion mode, the locking device 9 connects 10 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 15 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 20 compensation weight 7, an unbalanced mass is at least partially compensated.

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 25 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 30 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

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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, 5 4 are weakly coupled by the toothed belt 5. By additionally providing the oneway 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 10 by a user or an automatic handling device can be omitted.

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 15 transmission belt or the like to the drive shaft 3. Such a lateral geometry may result in a low height of the apparatus 50.

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 20 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.

As alternatives to the hollow shaft 11, another gear element such as a 25 cylinder or a pin or shank may be implemented as well.

With regard to the cogwheel system, both cogwheels 2, 4 may have the same number of cogs or teeth. The eccentricity rO 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 30 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 rO) as compared to the outer

- 25 -

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.

Fig. 2 illustrates an apparatus 50 according to another exemplary embodiment of the invention.

5 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.

10 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 15 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 20 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.

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 25 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.

Fig. 3 is a schematic illustration of an apparatus 50 according to an exemplary embodiment of the invention.

30 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 Zi 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

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of cogs or teeth zi is mounted on the eccentric cross-section 36 of the drive shaft 3. Toothed belt 5 has a number of cogs or teeth z2>zi. 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 5 support body 1 (for instance by fixation 6).

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.

When using a toothed belt 5, its shape always deviates from a circular 10 cross-section (x^y in Fig. 5) due to the eccentricity rO. 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.

In order to at least partially equilibrate unbalanced masses, it is possible 15 to provide the equilibration mass 7.

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.

For instance, cogwheel 2 may have z=60 teeth or cogs, and cogwheel 4 20 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 rO 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 25 providing a certain clearance, also for example r0=1.9 mm is possible.

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.

Fig. 4 shows a practical realization of an apparatus 50 according to the 30 schematic illustration of Fig. 3.

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.

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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.

5 6 to Fig. 9.

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 10 2,0 mm).

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 15 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.

In the following, an operation mode of using the apparatus 50 for an 20 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. 25 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 30 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,

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wherein the two cogwheels 2, 4 are always connected via toothed belt 5. At the upper cogwheel 4, the rotor 89 is fastened.

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 5 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 10 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 15 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.

20 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.

25 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.

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 30 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

- 29 -

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 5 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. 10 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).

15 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.

If the coupling body 5 is a rigid structure (such as an internally toothed 20 pinion or gearwheel) the scenario 2100 is obtained.

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

The inner diameter D (or more precisely the largest inner extension) of the coupling body 5 is larger, by the eccentricity r0, than twice of the radius ri 25 of the cogwheels 2, 4:

D = ri + ri + r0 = di + r0

Fig. 22 shows a plan view 2200, a three-dimensional view 2230 and a 30 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.

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

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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 (di = ri + ri) plus the eccentricity r0, i.e. D = ri + ri + r0 =di + r0.

5 b) The number z2 of teeth of the coupling body 5 should be larger, by at least one tooth, than the number zi of teeth of the cogwheels 2, 4: z2 > Zi + 1

c) The eccentricity r0 should be larger than the height h of the teeth (in order to enable a decoupling of the teeth from the coupling body 5): r0 > h d) The eccentricity r0 should be selected so that the number z2 of teeth 10 of the coupling body 5 is integer (plus some clearance, as the skilled person will understand): r0 = (L - Zi * p) / 2, wherein L = z2 * p is the circumferential length of the coupling body 5 and p is the tooth pitch.

Fig. 23 shows a plan view and Fig. 24 shows detailed views of a sample handling apparatus 2300 according to an exemplary embodiment of 15 the invention in which well plates (not shown) can be shaken.

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 20 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. 25 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.

It should also be noted that reference signs in the claims shall not be 30 construed as limiting the scope of the claims.

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Claims

1. A mechanism for generating an orbital motion for mixing, particularly for shaking, a fluidic sample (38) accommodated by a sample holder (14, 40), the mechanism comprising:

5 a stationary mounted or lockable first cogwheel (2) having a first through hole (30) and a plurality of first cogs (80) arranged along an outer circumference of the first cogwheel (2);

a movably mounted second cogwheel (4) having a second through hole (32) and a plurality of second cogs (82) arranged along an outer 10 circumference of the second cogwheel (4);

a drive shaft (3) having a concentric first section (34) and an eccentric second section (36), wherein the first section (34) is guided through the first through hole (30) and the second section (36) is guided through the second through hole (32);

15 a coupling body (5) having a plurality of third cogs (84) arranged along an inner circumference of the coupling body (5);

wherein the coupling body (5) is mounted with the first cogwheel (2) and with the second cogwheel (4) to engage part of the first cogs (80) and part of the second cogs (82) by part of the third cogs (84) to thereby generate 20 the orbital motion of the second cogwheel (4) and a sample holder (14, 40) to be mounted so as to follow a motion of the second cogwheel (4) upon rotating the first section (34) of the drive shaft (3).

2. The mechanism according to claim 1, wherein each of the first cogwheel (2) 25 and the second cogwheel (4) is a toothed belt disc and the coupling body (5) is a toothed belt.

3. The mechanism according to claim 1, wherein each of the first cogwheel (2) and the second cogwheel (4) is a sprocket and the coupling body (5) is a

30 sprocket chain.

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4. The mechanism according to any of claims 1 to 3, wherein the coupling body (5) is a flexible structure being deformable but basically non-elongatable upon rotating the drive shaft (3) so as to adapt its shape to follow motion of the second cogwheel (4) while maintaining the coupling between the first

5 cogwheel (2) and the second cogwheel (4).

5. The mechanism according to any of claims 1 to 3, wherein the coupling body (5) is a rigid, non-deformable structure which, upon rotating the drive shaft (3), follows, as a whole, motion of the second cogwheel (4) while

10 maintaining the coupling between the first cogwheel (2) and the second cogwheel (4).

6. The mechanism according to any of claims 1 to 5, wherein the coupling body (5) is a closed annular structure, particularly a structure being quasi-

15 rotationally symmetric in a force-free state.

7. The mechanism according to any of claims 1 to 6, wherein the coupling body (5) is an annular structure having an inner diameter which is larger than an outer diameter of the first cogwheel (2) and the second cogwheel (4),

20 particularly one times of an eccentricity (rO) of the second section (36) of the drive shaft (3) larger, wherein further particularly the largest inner extension of the coupling body (5) equals to an outer diameter of the first cogwheel (2) or the second cogwheel (4) plus an eccentricity (rO) of the second section (36) of the drive shaft (3).

25

8. The mechanism according to any of claims 1 to 7, comprising a support body(l) on which the second cogwheel (4), the drive shaft (3) and the coupling body (5) are mounted, wherein the first cogwheel (2) is configured as an integral portion of the support body (1).

30

9. The mechanism according to any of claims 1 to 8, wherein a number of the first cogs (80) is the same as a number of the second cogs (82).

10. The mechanism according to any of claims 1 to 9, wherein a number of the

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first cogs (80) and a number of the second cogs (82) are smaller than a number of the third cogs (84).

11. The mechanism according to any of claims 1 to 10, wherein a coupling 5 force resulting from the form closure of the coupling body (5) with both the first cogwheel (2) and the second cogwheel (4) is larger than a friction force, for instance a bearing force, between the first cogwheel (2), the second cogwheel (4) and the drive shaft (3).

10

12. The mechanism according to any of claims 1 to 11, wherein the coupling body (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

15 coupling body (5) limited by a rolling motion during which the coupling body

(5) rolls up on the first cogwheel (2).

13. The mechanism according to any of claims 1 to 12, comprising a drive unit (42), particularly an electric motor, being configured for rotating the first

20 section (34) of the drive shaft (3).

14. The mechanism according to any of claims 1 to 13, comprising a compensation weight (7) mounted asymmetrically on the drive shaft (3) and being configured so as to at least partially compensate for a mechanical load

25 acting on the drive shaft (3) upon generating the orbital motion.

15. The mechanism according to any of claims 1 to 14, configured for switching the sample holder (14, 40) for accommodating the fluidic sample (38) between an orbital motion mode for sample mixing, particularly for

30 shaking, in which the orbital motion is performed, and a rotary motion mode for sample separation, particularly for centrifuging, wherein the first cogwheel (2) in a locked stationarily mounted state, the second cogwheel (4), the drive shaft (3) and the coupling body (5) form an orbital motion generator (2 to 5) configured for generating the orbital motion of the sample holder (14, 40)

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when being operated in the orbital motion mode; the mechanism further comprising:

a gear element (11) being drivable by a drive unit (42) to move, particularly to rotate, selectively in a first direction (A) or in a second direction 5 (B) being inverse to the first direction (A);

a rotary motion generator (2, 4, 5) configured for generating a rotary motion of the sample holder (14, 40) when being operated in the rotary motion mode;

a one-way clutch arrangement (12, 13) configured for selectively: 10 coupling the gear element (11) with the orbital motion generator

(2 to 5) to transfer a driving force from the gear element (11) to the orbital motion generator (2 to 5) for generating the orbital motion when the gear element (11) is driven in the first direction (A) and to freewheel when the gear element (11) is driven in the second direction (B); or 15 coupling the gear element (11) with the rotary motion generator

(2, 4, 5) to transfer a driving force from the gear element (11) to the rotary motion generator (2, 4, 5) for generating the rotary motion when the gear element (11) is driven in the second direction (B) and to freewheel when the gear element (11) is driven in the first direction (A).

20

16. The mechanism according to claim 15, wherein the one-way clutch arrangement (12, 13) comprises:

a first one-way clutch (12) configured for coupling the gear element (11) with the orbital motion generator (2 to 5) to transfer the driving force 25 from the gear element (11) to the orbital motion generator (2 to 5) for generating the orbital motion when the gear element (11) is driven in the first direction (A) and to freewheel when the gear element (11) is driven in the second direction (B);

a second one-way clutch (13) configured for coupling the gear element 30 (11) with the rotary motion generator (2, 4, 5) to transfer the driving force from the gear element (11) to the rotary motion generator (2, 4, 5) for generating the rotary motion when the gear element (11) is driven in the second direction (B) and to freewheel when the gear element (11) is driven in the first direction (A).

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17. The mechanism according to claim 16, wherein the first one-way clutch (12) and the second one-way clutch (13) freewheel in mutually opposite directions and transmit force in mutually opposite directions.

5

18. The mechanism according to any of claims 15 to 17, wherein the gear element (11) is configured as a hollow shaft.

19. The mechanism according to claims 16 and 18, wherein the first one-way 10 clutch (12) is arranged between an interior curved surface of the hollow shaft

(11) and an exterior curved surface of a drive shaft (3) of the orbital motion generator (2 to 5).

20. The mechanism according to claims 16 and 18, wherein the second one-15 way clutch (13) is arranged between an exterior curved surface of the hollow shaft (11) and an interior curved surface of a movably mounted cogwheel (2) of the rotary motion generator (2, 4, 5).

21. The mechanism according to any of claims 15 to 20,

20 wherein the rotary motion generator (2, 4, 5) comprises the second cogwheel (4), the coupling body (5) and the selectively lockable first cogwheel (2) in an unlocked movably mounted state and being coupled to the gear element (11) via the one-way clutch arrangement (12, 13);

wherein the coupling body (5) is mounted with the first cogwheel (2) 25 and with the second cogwheel (4) to engage part of the first cogs (80) and part of the second cogs (82) by part of the third cogs (84) to thereby generate the rotary motion of the second cogwheel (4) and a sample holder (14, 40) to be mounted so as to follow a motion of the second cogwheel (4) upon rotating the gear element (11) in the second direction (B).

30

22. The mechanism according to claim 21, further comprising a cogwheel locking element (9) configured for selectively locking the first cogwheel (2) in the locked stationarily mounted state or for unlocking the first cogwheel (2) in the unlocked movably mounted state.

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23. The mechanism according to any of claims 15 to 22, further comprising a shaft locking element (10) configured for selectively locking the drive shaft (3) in a locked stationarily mounted state, particularly in the rotary motion mode,

5 or for unlocking the drive shaft (3) in an unlocked movably mounted state, particularly in the orbital motion mode.

24. The mechanism according to any of claims 15 to 23, comprising a support body (1) accommodating the components (2 to 5, 11 to 13) of the mechanism

10 and comprising a lid (45) to be attached onto the support body (1), wherein the support body (1) and the lid (45) are configured correspondingly to one another so that upon attaching the lid (45) onto the support body (1), the mechanism is triggered, particularly by a lid attaching sensor configured for sensing attachment of the lid (45) onto the support body (1), to be switched 15 from the orbital motion mode to the rotary motion mode.

25. An apparatus (50) for handling a fluidic sample (38), the apparatus (50) comprising:

a mechanism according to any of claims 1 to 24 for generating an orbital 20 motion for mixing, particularly for shaking, the fluidic sample (38) to be accommodated by a sample holder (14, 40); and the sample holder (14, 40) for accommodating the fluidic sample (38) and being coupled to the mechanism to follow a motion of the second cogwheel (4).

25

26. The apparatus (50) according to claim 25, wherein the sample holder (14, 40) comprises one or more accommodation sections (90, 92, 94, 96) each having an accommodation recess each configured for receiving a container (97) including one or more fluidic samples (38).

30

27. The apparatus (50) according to claim 26, wherein each of the one or more accommodation sections (90, 92, 94, 96) is mounted to be pivotable around a pivoting axis being perpendicular to a rotation axis of the drive shaft (3) so as to be pivoted upon exceeding a predefined rotation force.

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28. A method of generating an orbital motion for mixing, particularly for shaking, a fluidic sample (38) accommodated by a sample holder (14, 40), the method comprising:

5 stationarily mounting or locking a first cogwheel (2) having a first through hole (30) and a plurality of first cogs (80) arranged along an outer circumference of the first cogwheel (2);

movably mounting a second cogwheel (4) having a second through hole (32) and a plurality of second cogs (82) arranged along an outer 10 circumference of the second cogwheel (4);

guiding a first concentric section of a drive shaft (3) through a first through hole (30) and guiding a second eccentric section of the drive shaft (3) through the second through hole (32);

mounting a coupling body (5), which has a plurality of third cogs (84) 15 arranged along an inner circumference of the coupling body (5), with the first cogwheel (2) and with the second cogwheel (4) to engage part of the first cogs (80) and part of the second cogs (82) by part of the third cogs (84);

rotating the first section (34) of the drive shaft (3) to thereby generate the orbital motion of the second cogwheel (4) and a sample holder (14, 40) 20 mounted so as to follow a motion of the second cogwheel (4).