CENTRIFUGE

Description

[0001] The present invention relates to a centrifuge for cleaning a reaction vessel unit having a rotor and a rotor chamber in which the rotor is arranged and rotatably mounted, wherein the rotor has a receiving area for receiving the reaction vessel unit.

[0002] EP 937502 A2 describes a method for handling a microtiter plate, wherein the microtiter plate is cleaned by centrifugation. For this purpose, the microtiter plate is placed in the rotating housing via a conveyor belt so that the openings of the microtiter plate are directed away from the rotation axis.

[0003] WO 2015 / 018878 A1 discloses another centrifuge which has an elastic arm with which microtiter plates can be pulled into or pushed out of a centrifuge rotor. The rotor is only very close to the surrounding housing and also to the drainage channel located in the lower area. This short section is intended to use the resulting circulating wind to drive the liquid leaking from the reaction vessels into the drainage channel and then pump it out using a pump. Due to the short distance, there is a risk that the liquid level will be above the drainage channel. This can cause the rotor to immerse itself in the liquid while rotating. This is particularly critical when the liquid is a washing solution or detergent, as the rotor then foams the liquid.This foam can quickly fill a large portion of the rotor's volume and escape through the door. Furthermore, the foaming material cannot be effectively pumped out by the pump described above, but rather remains in the rotor chamber or the drainage channel. The close proximity of the rotor to the drainage channel is primarily due to the cylindrical shape of the rotor chamber, which is designed to generate the desired circulating wind.

[0004] It is known that in cylindrical centrifuge rotor chambers, circulating winds are generated by the rotating rotor. In this context, reference is made to US 2007 / 0037684 A1, DE 103 55 179 A1, DBP 1033446, EP 2 705 903 A1, and DE 2404036.

[0005] DE 10 2008 042 971 A1 discloses a centrifuge in which a magnetic device is integrated in order to hold magnetizable particles within a reaction vessel by means of the magnetic force.

[0006] CN 102175855 A discloses a fully automatic 360° plate washer. The rotation axis of this machine runs parallel to the horizontal plane, allowing multiple plates to be washed simultaneously in one cabinet, thereby increasing efficiency and significantly reducing costs.

[0007] US 4,953,575 / DE 39 32 456 relates to a washing device for cuvettes. For this purpose, the cuvettes are placed in a holder within a rotor. The liquid is removed from the cuvettes by rotating the rotor. The disclosed centrifuge housing has an opening at its lowest point through which the removed liquid can exit the housing.

[0008] JP 2009264927 A discloses a device comprising a drum in which a microplate can be placed. The drum can be loaded with multiple microtiter plates, which then rotate about a horizontal axis of rotation. The drum is loaded with the microtiter plates such that their openings are directed toward the interior of the drum.

[0009] The invention is based on the object of providing a centrifuge for cleaning a reaction vessel unit, which has a rotor and a rotor chamber in which the rotor is rotatably mounted, so that the structure of the centrifuge is simpler than in the conventional centrifuges described above and reliable operation is possible.

[0010] A further object of the present invention is to further develop a centrifuge for cleaning a reaction vessel unit as described above in such a way that the risk of contamination of the reaction vessel units is reduced.

[0011] The basic object of the present invention is to provide a centrifuge for cleaning a reaction vessel unit, whereby a quick, thorough and reliable cleaning should be possible.

[0012] One or more of the aforementioned objects are achieved by the subject matter of the independent claims. Advantageous embodiments are specified in the respective subclaims.

[0013] According to a first aspect of the present invention, a centrifuge for cleaning a reaction vessel unit is provided, comprising a rotor and a rotor chamber in which the rotor is arranged and rotatably mounted, wherein the rotor has a receiving area for receiving the reaction vessel unit, and the rotor chamber is delimited by a housing, wherein the housing has a drainage channel below the rotor and the inner surfaces of the housing adjacent to the channel form a funnel which opens into the channel, characterized in that the housing comprises an upper and a lower shell, wherein the upper shell has a channel-shaped shape with a semicircular cross-section, and a loading and unloading device is provided, which comprises a rigid displacement rod for positioning a reaction vessel unit in or for removing a reaction vessel unit from the rotor, wherein the displacement rod is arranged displaceably in such a way thatthat it can be moved between an unloading position, in which it extends through the rotor in the rotor space, and a loading position, in which it is withdrawn at least from the area of ​​the rotor space that is occupied by the rotor during one revolution, and a linear drive for moving the sliding rod between the unloading position and the loading position.

[0014] By providing the funnel below the rotor, liquids ejected from the reaction vessel unit are collected in the trough so that they can flow out of the trough.

[0015] Surprisingly, it has been shown that no suction pump is necessary to drain the liquids from the centrifuge. Instead, the wind generated by the rotation of the rotor and the design of the funnel are sufficient to ensure that the liquids are reliably collected in the chute and drained away. Such a centrifuge can therefore be operated without a suction pump. It is even advantageous to operate the centrifuge without a suction pump, because if the suction pump fails, it creates a flow resistance that makes further operation of the centrifuge impossible, as the liquid can then no longer be drained from the centrifuge. Omitting the suction pump also represents a considerable simplification and cost saving. Using a centrifuge with a suction pump also requires that the centrifuge's control system be coupled to the suction pump, which entails additional technical complexity.

[0016] All of this can be avoided by the clever design of the housing, whereby the operation of the centrifuge is even more reliable, since the removal of the liquid from the rotor chamber cannot be affected by the failure of a suction pump.

[0017] Furthermore, by eliminating the suction pump, the flow path from the centrifuge housing to a collection container can be made significantly shorter and simpler. This container is easily accessible for maintenance work.

[0018] The inner surfaces of the housing forming the funnel have a curvature that is significantly greater than the curvature of a cylindrical surface covered by the rotor's outer edges during one revolution. The radius of curvature of these inner surfaces forming the funnel is preferably at least 0.5 m, in particular at least 1 m, and is preferably infinite, meaning that the inner surfaces forming the funnel are flat.

[0019] The inner surfaces forming the funnel, hereinafter referred to as funnel surfaces, preferably extend laterally from the channel to the outer edge of a rotational volume of the rotor, i.e., the funnel and the channel cover the entire vertical projection of the rotor in plan view. In other words, this means that the rotor, in any position, even in a horizontal position, does not extend beyond the lateral edge of the funnel.

[0020] Such a design of the funnel surfaces with a slight curvature has the effect that, as the rotor rotates, it comes closest to a central area of ​​the funnel surface and is at a greater distance from both the outer edge and the central edge, which is adjacent to the trough. In these areas at a greater distance from the rotor, there is a lower airflow when the rotor rotates, so that the liquids collect here and flow along the funnel surface.

[0021] The distance of the trough from a rotational axis around which the rotor rotates is preferably at least 1.31 times the maximum radius of the rotor, and in particular at least 1.2 times or 1.3 times the maximum radius of the rotor. This distance is measured from the upper edge of the trough to the rotational axis. This distance from the rotational axis, which is slightly larger than the radius of the rotor, creates a free space in the funnel in which liquid can temporarily accumulate. If a reaction vessel unit with large-volume reaction vessels that are almost completely filled is cleaned, a large portion of the liquid contained in the reaction vessels is emptied at once during the first or first few rotations of the rotor. This liquid can collect in this free space without coming into contact with the rotating rotor. The liquid can then gradually flow out of this free space via the trough.

[0022] The inner surface of the housing is preferably coated with a smooth layer, at least in the area of ​​the funnel and the channel. This layer can be a hydrophobic layer, which is advantageous for draining an aqueous solution. This layer can be made of PTFE (polytetrafluoroethylene), for example.

[0023] The rotational axis of the rotor is preferably arranged parallel to a base of the housing. As a result, the rotational axis of the rotor is arranged horizontally during operation. Such an arrangement of the rotational axis allows the centrifuge to be easily loaded with a reaction vessel unit, as the unit can be inserted into the rotor chamber with the openings of the reaction vessels facing upwards. In reaction vessel units with large-volume reaction vessels (e.g. microtiter plates with 96 reaction vessels), the liquid does not necessarily adhere completely to the reaction vessels due to capillary forces. With a horizontal arrangement of the rotational axis, such reaction vessel units can be turned once after being inserted into the rotor chamber or into the rotor by rotating the rotor 180° so that their openings point downwards towards the funnel. A large part of the liquid then flows out of the reaction vessel units and drips directly into the funnel.The remaining amounts of liquid in the reaction vessels, which are adhering due to surface tension, can then be removed by centrifugation.

[0024] The channel is preferably inclined relative to the base of the housing. At the lower end of the channel, it opens into an outlet opening in the housing. A hose can be connected to this outlet opening, which is used to direct the liquid into a container. This arrangement should be designed so that no backpressure develops when the liquid is drained. This can be achieved, for example, by providing a ventilation opening in the container.

[0025] Furthermore, it may be expedient for the housing to have a ventilation opening leading into the rotor chamber. If the rotor chamber is otherwise essentially hermetically sealed, a negative pressure could develop in the rotor chamber when the liquid flows out and completely fills the cross-section of the outlet opening, which would counteract further flow of the liquid. This is prevented by providing a ventilation opening. A filter, such as an activated carbon filter, is preferably provided in the ventilation opening to prevent germs from outside from entering the rotor chamber. Such a ventilation opening is preferably provided in the region of an end wall of the housing onto which liquid from the reaction vessel unit is not directly sprayed during centrifugation. The ventilation opening can also be shielded from the rotor chamber by a screen, wherein the screen is arranged at a distance from the ventilation opening.

[0026] Such a centrifuge has a housing with an opening for feeding and removing a reaction vessel unit to and from the rotor chamber. This opening can be closed by a door, which is typically operated automatically. If this door does not seal perfectly, it forms a ventilation opening even when closed. The door is preferably provided with a filter element arranged on its closing edges, so that the air flowing in at the edges of the door must pass through the filter.

[0027] According to a further aspect of the present invention, a centrifuge for cleaning a reaction vessel unit is provided, which comprises a rotor and a rotor chamber in which the rotor is arranged and rotatably mounted. The rotor has a receiving area for receiving a reaction vessel unit. The centrifuge is provided with a housing that delimits the rotor chamber. Furthermore, the centrifuge has a drive for rotating the rotor. The centrifuge is designed with an exchange module that comprises the rotor and a housing section of the housing, wherein this housing section encloses the rotor. The exchange module is designed to be detachable from the remaining parts of the centrifuge.

[0028] This makes it possible, after one or more uses of a centrifuge with such an exchange module, to remove the exchange module from the remaining parts of the centrifuge and clean it and / or replace it with another exchange module. This exchange module preferably contains only mechanical elements, such as the rotor, housing, bearings, etc., and no electronic components. This makes it possible to autoclave the exchange module and thus clean and sterilize it without leaving any residue.

[0029] In principle, such a centrifuge can be cleaned by introducing a cleaning agent, which is, for example, poured into the reaction vessel of a reaction vessel unit and then centrifuged in the centrifuge, or introduced into the rotor chamber via appropriate nozzles. However, such cleaning is not always completely residue-free.

[0030] A replacement module comprises a small number of mechanical parts, which account for only a small portion of the manufacturing costs of the entire centrifuge. Such a centrifuge has a drive for rotating the rotor, a control device for controlling the rotational movement of the centrifuge, and other components, such as a dispensing device and / or a loading and unloading device. Such a loading and unloading device can be relatively complex, particularly if it is equipped with a detection device for determining the position of a sliding rod of the loading and unloading device. By replacing the replacement module, a cost-effective component of the centrifuge can be replaced, while the remaining components can be used unchanged.This replacement module can therefore be a consumable item that is used only once or for a predetermined period of time or for a predetermined number of cleaning processes. If the replacement module is intended as a consumable item, it can also be expedient to provide parts thereof from plastic, in particular as injection-molded items, such as the rotor and / or the housing section of the replacement module. On the other hand, the replacement module can also be designed to be heat-resistant, so that it can, for example, reliably withstand temperatures of up to 100°C and preferably up to 150°C, so that the replacement module can be cleaned by autoclaving. Because the replacement module is separable from the electronic components of the centrifuge, it is possible to design the replacement module to be heat-resistant. This allows residue-free cleaning and reuse of the replacement module.

[0031] Such an exchange module preferably has a fastening mechanism with which it can be easily and quickly coupled to the other parts of the centrifuge, fixed and coupled to the other functional elements, such as drive device, pipetting device, camera and / or loading and unloading device in such a way that the function of these elements can be carried out.

[0032] The centrifuge according to one of the embodiments explained above is provided with a loading and unloading device comprising a rigid displacement rod for positioning a reaction vessel unit in or for removing a reaction vessel unit from the rotor. The displacement rod is arranged such that it can be moved between an unloading position, in which it extends through the rotor in the rotor chamber, and a loading position, in which it is withdrawn from at least the area of ​​the rotor chamber occupied by the rotor during one rotation. A linear drive is provided for moving the displacement rod between the unloading position and the loading position.

[0033] A coupling element can be arranged at a free end of the displacement rod located in the rotor chamber. The coupling element serves to reconnect the displacement rod to a reaction vessel unit or a support unit for a reaction vessel unit.

[0034] The coupling element can have a locking element which can engage with a counter-locking element provided on the reaction vessel unit or on the carrier unit, wherein at least the locking element or the counter-locking element is elastically mounted.

[0035] The counter-locking element of the reaction vessel unit or the carrier unit can be elastically mounted and coupled to a locking bracket, so that the locking bracket can pivot between two positions, wherein an unlocking position is assumed when the locking element and the counter-locking element are locked together, and a locking position is assumed when the locking element and the counter-locking element are separated from each other, wherein the locking bracket has a locking element which can engage with a corresponding counter-locking element in a locking position.

[0036] The sliding rod preferably has a smooth surface.

[0037] The displacement rod can be hollow and open at the rear end facing away from the rotor chamber, and a threaded rod can be provided coaxially to the displacement rod. The threaded rod can be in meshing engagement with a thread connected to the displacement rod, so that a rotational movement of the threaded rod causes a translational movement of the displacement rod. The threaded rod dips into the displacement rod at the rear end. The displacement rod can be guided through an opening in a housing wall, with a sealing element being provided in the region of the opening to seal the displacement rod from the housing wall. If a replacement module is provided, then an additional housing wall is preferably provided which is not part of the replacement module and in which the opening is formed with a sealing ring.A further sealing element can be provided in a corresponding opening in the housing wall of the replacement module.

[0038] A detection device may be provided to determine the position of the sliding rod. This detection device is preferably an optical detection device.

[0039] The centrifuge may have a pipetting or dispensing unit, wherein the dispensing unit preferably has a plurality of pipetting or dispensing nozzles. The dispensing nozzles are preferably arranged adjacent to one another along a line, with this line extending transversely to the direction of movement of the reaction vessel unit during loading or unloading. The nozzles of the dispensing unit are preferably arranged adjacent to an opening for loading and unloading the centrifuge with the reaction vessel unit.

[0040] Furthermore, an optical detection unit can be provided, which is arranged adjacent to the rotor chamber in the movement space of the reaction vessel unit for scanning the reaction vessel unit. This detection unit comprises, for example, a line-scan camera for scanning a reaction vessel unit in a line-like manner, with each scanning line aligned approximately perpendicular to the direction of movement of the reaction vessel unit.

[0041] The detection unit can comprise a color camera for spectrally scanning a reaction vessel unit. The optical detection unit can also be configured for 3D scanning.

[0042] The centrifuge may have an evaluation device with which the signals obtained by the optical detection device are automatically evaluated according to one or more of the following parameters: Color of the contents of at least one reaction vessel of the reaction vessel unit, fill level of at least one reaction vessel of the reaction vessel unit, position of the reaction vessel unit, type of the reaction vessel unit.

[0043] A spraying device for spraying a decontamination solution or cleaning solution into the interior can be provided in the rotor chamber.

[0044] The housing may be provided with one or more windows in the rotor chamber area.

[0045] The centrifuge may comprise a control device which detects the position of a reaction vessel unit or of a carrier of a reaction vessel unit and transmits this via an interface to another device, such as a robot or to another component in the centrifuge, such as a dispensing unit, so that the another device or the other component can receive the position of the reaction vessel unit or of the carrier of the reaction vessel unit.

[0046] Some of the components explained above are described and illustrated in DE 10 2016 101 163 and in the international patent application PCT / EP 2017 / 051289, which is why reference is made to these documents in their entirety.

[0047] The aspects, components and parts of a centrifuge explained above can basically be freely combined as desired.

[0048] According to a further aspect of the present invention, a method for cleaning a reaction vessel unit using a centrifuge with a rotor is provided. The reaction vessel unit is arranged in the rotor with the openings of the reaction vessels facing radially outward. The rotor is rotated together with the reaction vessel unit about a rotational axis, so that the contents of the reaction vessels are ejected. Solely by the rotational movement of the rotor and gravity, the contents of the reaction vessels are driven into the channel and from there outward. No suction pump is used to suck the liquid out of the rotor chamber.

[0049] According to a further aspect of the present invention, a method for cleaning a reaction vessel unit using a centrifuge with a rotor is provided, wherein the reaction vessel unit is arranged in the rotor with the openings of the reaction vessels facing radially outward. The rotor is rotated together with the reaction vessel unit about a rotation axis, so that the contents of the reaction vessels are ejected. After cleaning one or more reaction vessel units, a replacement module comprising a housing section and the rotor is separated from the remainder of the centrifuge and is either cleaned or replaced with another replacement module.

[0050] This method can be used with a centrifuge as explained above.

[0051] The invention is explained in more detail below by way of example with reference to the drawings.

[0052] The drawings show in: Figure 1a part of a housing of a centrifuge in perspective view, Figure 2the part of the housing from Figure 1 in a sectional view looking diagonally from the front, Figure 3 the part of the housing from Figure 1 in a longitudinal section, Figure 4Parts of a centrifuge with the housing part made of Figure 1 in a longitudinal section, Figure 5 schematically shows a further embodiment of a centrifuge with an exchange module, and Figure 6 schematically shows a further embodiment of a centrifuge with an exchange module in a longitudinal section.

[0053] A centrifuge 1 according to the invention ( Figure 4 ) has a rotor 2, a housing 3, a drive device 4 for rotating the rotor 2 about a rotation axis 5.

[0054] The rotor has at least one receiving area 6 for receiving a reaction vessel unit 7. The reaction vessel unit 7 is typically a microtiter plate. Such microtiter plates can be configured with a varying number of reaction vessels. Microtiter plates with six to 4096 reaction vessels are typical, with microtiter plates with 96, 384, or 1536 reaction vessels being the most common versions. In microtiter plates with 384 or 1536 reaction vessels, the individual reaction vessels are so thin that a liquid normally adheres to them due to capillary forces alone, so that even if such a microtiter plate is arranged with its openings facing downwards, the liquid does not flow out. This does not apply to microtiter plates with fewer, each larger, reaction vessels. Such a reaction vessel unit 7 can be inserted into a receiving device 6 on its own or on a carrier unit.Preferably, a carrier unit is used which has a coupling element that can be coupled to a loading and unloading device 8. Such a loading and unloading device is described, for example, in DE 10 2016 101 163. It is explained in more detail below.

[0055] The housing 3 defines a rotor chamber 9. In the present embodiment, the region of the housing 3 defining the rotor chamber 9 is formed from a lower shell 10, an upper shell 11, a front end wall 12, and a rear end wall 13. Further parts of the housing, which are not shown in the attached figures, adjoin the rear end wall.

[0056] The front end wall 12 and the rear end wall 13 each contain a ball bearing 14, in which a continuous shaft 15 of the rotor 2 is rotatably mounted. The center line of the shaft 15 forms the rotation axis 5. The rotation axis 5 runs parallel to a base surface 16 formed by the underside of the lower shell 10.

[0057] The rear end of the shaft 15 is coupled to the drive device 4. The further part of the housing, which adjoins the rear of the housing, contains the drive device 17, the loading and unloading device 8, and a central control device (not shown) with which all components of the centrifuge 1 are controlled.

[0058] A balcony 18 is attached to the outside of the front end wall 12, which serves to accommodate a reaction vessel unit 7. At the level of the balcony 18, a loading and unloading opening 19 is formed in the front end wall 12, through which a reaction vessel unit 7 can be inserted into and removed from the rotor chamber 9. The loading and unloading opening 19 is provided with a pivoting door 20 so that the rotor chamber can be closed.

[0059] Adjacent to this door 20, a dispenser unit with several dispenser nozzles and / or an optical detection unit, in particular in the form of a line scan camera, can be provided.

[0060] The loading and unloading device 8 has a displacement rod (not shown) which can be moved horizontally through the rotor chamber 9 with its free end through a through-opening 21 in the rear end wall 13. The loading and unloading device 8 has a linear drive for this purpose, so that the displacement rod can be moved linearly along its longitudinal direction. The displacement rod has a coupling element at its free end, which can be coupled to a corresponding coupling element on the carrier unit or on a reaction vessel unit 7, so that the carrier unit with a reaction vessel unit or the reaction vessel unit can be moved directly by moving the displacement rod from the balcony 18 through the loading and unloading opening 19 into the rotor chamber 9, wherein the rotor 2 is arranged with a receiving area 6 adjacent to the loading and unloading opening 19, so that the carrier unit orthe reaction vessel unit is moved into the receiving area 6 of the rotor 2. The coupling between the displacement rod and the carrier unit or the reaction vessel unit 7 can be released, so that the carrier unit or the reaction vessel unit is freely movable in the rotor 2 and the rotor can be rotated accordingly with this unit.

[0061] By means of the sliding rod of the loading and unloading device 8, the carrier unit or reaction vessel unit 7 can be pushed from the receiving area 6 of the rotor 2 through the loading and unloading opening 19 back onto the balcony 18. The reaction vessel unit 7 can be removed from the balcony 18, for example, by means of a robot.

[0062] The lower shell 10 has a groove 22 which runs approximately parallel to the rotation axis 5. The groove 22 extends from the rear end wall 13 to the area of ​​the front end wall 12, wherein it is inclined or sloping towards the front ( Figure 4 ). On the front of the lower bowl 10, an outlet opening 23 is formed, at which the channel 22 opens. At the outlet opening 23, a connection pin 24 is arranged, to which a hose 25 can be connected. The hose 25 usually opens into a receiving container (not shown) in which the liquids are collected which are spun out of the reaction vessels of the reaction vessel unit 7 in the centrifuge 1. The container preferably has a ventilation opening or the hose passes through the container with some play so that liquid flowing out of the centrifuge through the hose 25 does not create any back pressure in the container.

[0063] The lower shell 10 has inner surfaces adjacent to the channel 22, which extend from an upper edge of the channel 22 in an obliquely rising direction outwards ( Fig. 2 ). These inner surfaces thus form a funnel 26 and are referred to below as funnel surfaces 27. The funnel surfaces 27 are inclined at an angle of approximately 30° to 60° relative to the horizontal. Essentially planar means that the funnel surfaces have a radius of curvature of more than 0.5 m and preferably more than 1 m. In the present embodiment, the funnel surfaces 27 extend laterally beyond the area of ​​the rotor 2, even when it is in its horizontal position.

[0064] From the outer edge of the funnel 26 or the funnel surfaces 27, the inner surfaces of the lower shell 10 extend approximately vertically upwards. They thus form vertical surfaces 28.

[0065] The upper shell 11, which has a groove-like shape with a semicircular cross-section, is attached to the upper edge of the lower shell 10. The inner surface of the upper shell 11 merges flush with the vertical surface 28. The cross-section of the housing 3 is therefore not cylindrical, as is known from the prior art, but rather has a cylindrical curvature only in the upper region of the shell 11, whereas the lower shell 10 has a funnel-shaped cross-section and ends in the groove 22. The groove 22 is slightly offset downwards from the funnel-shaped lower shell 10 and has two approximately vertically arranged side walls 37a, 37b. The groove itself is designed with an incline so that any liquid contained therein drains away.

[0066] In the present embodiment, the lower shell 10 and the upper shell 11 are made of metal. The inner surfaces of the lower shell 10 and the upper shell 11 are coated with a smooth plastic layer, so that liquids ejected from the reaction vessels of the reaction vessel units 7 quickly flow along the inner surfaces, are guided by the funnel 26 to the channel 22, and there exit the rotor chamber 9. The plastic layer is made of PTFE.

[0067] The upper edge of the channel 22 is spaced from the rotation axis 5 by at least 1.32 times the maximum radius of the rotor 2. This creates a free space in the funnel 26 that is not touched by the rotor 2 during one rotation. Liquid can collect in this free space. Figure 2A maximum level 29 of the liquid is shown, which can accumulate in the funnel 26 without coming into contact with the rotor. This makes it possible, in the case of large-volume reaction vessels of a reaction vessel unit 7, to empty the majority of the liquid contained therein at once, collecting it in the funnel 26, and allowing it to gradually flow out through the outlet opening 23.

[0068] Furthermore, due to the large distance between the trough 22 and the rotor and the resulting large cross-section, the air flow generated by the rotor during rotation is at its lowest in this area, so that liquid can settle at the bottom of the funnel, i.e., in the trough 22, and flow out of the trough 22 through the outlet opening 23. Due to the low flow velocity, the risk of liquids located in the funnel-shaped area adjacent to the trough 22 being driven upwards by the air flow is also low.

[0069] Since the channel is delimited by approximately vertical side walls 37a, 37b, even if an air flow is generated in the direction of rotation 38, this cannot drive the liquid out of the channel. Once a liquid is in the channel 22, it is trapped there and can only exit through the outlet opening 23. Figure 2 In the embodiment shown, an air flow can strike the side wall 37a, which is arranged downstream of the channel 22 in the direction of rotation 38 of the rotor. However, since the side wall 37a is approximately perpendicular to the flow direction, the liquid in the channel can no longer be driven back into the rotor chamber. In principle, a channel with an approximately vertical side wall on the side of the channel 22 downstream of the direction of rotation 38 is sufficient. However, from a manufacturing perspective, it is expedient to produce a channel with two approximately vertical side walls 37a, 37b.

[0070] This design of the funnel 26 and the channel 22 eliminates the need for a suction pump, as is known from the prior art.

[0071] In the following, another embodiment of a centrifuge is explained, which is roughly simplified schematically in Figure 5 Unless otherwise stated, this embodiment is constructed in the same way as the embodiment explained above. Therefore, the same reference numerals are used for the same parts.

[0072] The centrifuge 1, in turn, has a housing 3 with a rotor 2, a drive device 4, a balcony 18, a loading and unloading device 8, and a central control device 30. A rotor chamber 17 is closed at the top by a pivoting lid 31. The pivoting lid 31 is connected to the rest of the housing 3 by a pivot joint, specifically in the area of ​​the rear end wall 13. The rotor 2 is again mounted in the rotor chamber 9, which, in this embodiment, is part of a replacement module 32. The replacement module 32 has a replacement module housing 33 that essentially completely encloses the rotor 2 and fits into the rotor chamber 17 of the housing 3 with minimal play. The replacement module housing 33 has a front end wall 12a, a rear end wall 13a, a lower shell 10a, and an upper shell 11a. These walls 12a, 13a, respectively.Shells 10a, 11a are thin-walled walls which preferably form inner surfaces that correspond to the shape of the inner surfaces of the rotor chamber 9 of the first embodiment explained above.

[0073] When the cover 31 is open, the exchange module 33 can be removed from the housing 3 in the vertical direction 34 and replaced with another exchange module 33 or cleaned and then reinserted. When the cover 31 is opened, the loading and unloading device 8 and the drive device 4 are each moved horizontally a short distance away from the rotor chamber 17. As a result, the free end of the sliding rod of the loading and unloading device 8 and a shaft journal of the drive device 4 are pulled out of the rotor chamber 17 so that they do not get in the way of an upward movement of the exchange module housing 33. When the pivoting cover 31 is closed, the loading and unloading device 8 and the drive device 4 are pushed back horizontally in the direction of arrow 34.If a replacement module is located in the housing 33 in the rotor chamber 17, the shaft journal of the drive device 4 is coupled to the shaft of the rotor 2 and the free end of the sliding rod into a corresponding through-opening of the replacement module housing 33. As a result, the replacement module housing 33 is automatically coupled into the housing 3 and connected to the corresponding functional parts.

[0074] At the lower edge, the replacement module housing 33 again has a groove 22 which opens into an outlet opening 23 of the housing 3.

[0075] Figure 6has a variant of the second embodiment, in which, instead of a pivotable cover 31 for delimiting the rotor chamber 17, a removable hood 35 is provided, which has the front end wall 12 and a ceiling wall 36 that delimits the rotor chamber 17 at the top. This hood 35 can be pulled off in the horizontal direction (arrow 34), so that the replacement module housing 33 is exposed. The replacement module housing 33 can be pulled off in the horizontal direction (arrow 34) from the remaining part of the housing 3. No mechanism for moving the drive device 4 or the loading and unloading device 8 is provided here.

[0076] When the housing 3 is opened, the replacement module housing 33 can be replaced or removed and reinserted for cleaning.

[0077] If the replacement module housing 33 is to be cleaned, for example by autoclaving, then it is expedient for it to be made of heat-resistant materials, such as metal. However, it may also be expedient to completely replace the replacement module after a certain period of use. On the one hand, the reaction vessel units can be cleaned of substances that attack the replacement module 32 and, for example, corrode it. In this case, it is expedient to completely replace the replacement module 32 after a predetermined operating period of several weeks to several months. If such replacement modules 32 are used as consumables, it may also be expedient to construct them essentially from plastic. The replacement module housing 33 is preferably made of a material with high chemical resistance, such as PTFE. The rotor is preferably made of a hard plastic material, in particular an injection-molded part.

[0078] Both the hood 35 and the pivoting cover 31 can be attached to the rest of the housing 3 using a locking or snap-in mechanism. List of reference symbols

[0079] 1 Centrifuge 2 Rotor 3 Housing 4 Drive unit 5 Rotation axis 6 Pick-up area 7 Reaction vessel unit 8 Loading and unloading device 9 Rotor chamber 10 Lower bowl 10a Lower bowl 11 Upper bowl 11a Upper bowl 12 Front end wall 12 Front end wall 13 Rear end wall 13a Rear end wall 14 Ball bearing 15 Shaft 16 Standing surface 17 Rotor chamber 18 Balcony 19 Ventilation opening 20 Door 21 Through opening 22 Trough 23 Outlet opening 24 Connection pin 25 Hose 26 Funnel 27 Funnel surface 28 Vertical surface 29 Level 30 Central control device 31 Pivoting lid 32 Exchange module 33 Exchange module housing 34Arrow 35Cover 36Ceiling wall 37aSide wall 37bSide wall 38Direction of rotation

Claims

1. A centrifuge (1) for cleaning a reaction vessel unit (7) comprising a rotor (2) and a rotor chamber (9) in which the rotor (2) is arranged and rotatably mounted, the rotor (2) comprising a receiving area (6) for receiving the reaction vessel unit (7), and the rotor chamber (9) being delimited by a housing (3), the housing (3) comprising a discharge channel (22) underneath the rotor (2) and the inner surfaces of the housing (3) forming a funnel (26) adjacent to the channel (22), which funnel opens into the channel (22), characterized in that the housing (3) comprises an upper shell (11) and a lower shell (10), the upper shell (11) having a channel-shaped form of a semicircular shape in cross-section, and a loading and unloading device (8) being provided, which comprises a rigid displacement rod for positioning the reaction vessel unit (7) in the rotor (2) or for removing the reaction vessel unit (7) from the rotor (2), the displacement rod being slidably arranged such that it can be moved between an unloading position, in which it extends through the rotor (2) in the rotor space (9), and a loading position, in which it is withdrawn at least from that area of the rotor space (9) which is occupied by the rotor (2) during one revolution, and a linear drive for moving the displacement rod between the unloading position and the loading position.

2. The centrifuge (1) according to claim 1, characterized in that the distance of the channel (22) from an axis of rotation (5), about which the rotor (2) rotates, is at least 1.1 times the radius of the rotor (2) and preferably at least 1.2 times the radius of the rotor (2), and / or the channel (22) comprises an inclination with respect to a standing surface (16) of the housing (3), and / or the channel (22) comprises at least one approximately vertically arranged side wall (37a).

3. The centrifuge (1) according to claim 1 or 2, characterized in that the inner surface of the housing (3), at least in the area of the funnel (26) and of the channel (22), is coated with a smooth, preferably hydrophobic layer, the layer preferably being formed from PTFE.

4. The centrifuge (1) according to any one of claims 1 to 3, characterized in that an axis of rotation (5) of the rotor (2) extends parallel to a standing surface (16) of the housing (3) and / or characterized in that the housing (3) comprises a ventilation opening (19) in which an air filter is preferably arranged.

5. The centrifuge (1) for cleaning a reaction vessel unit (7), according to any one of claims 1 to 4, comprising a rotor (2) and a rotor space (9) in which the rotor (2) is arranged and rotatably mounted, the rotor (2) comprising a receiving area (6) for receiving the reaction vessel unit (7), and a housing (3) which delimits the rotor chamber (9), a drive for rotating the rotor (2), wherein the centrifuge (1) comprises an exchange module (32) which encompasses the rotor (2) and a housing portion of the housing (3), this housing portion enclosing the rotor (2), and the exchange module (32) being designed such that it can be detached from the remaining parts of the centrifuge (1).

6. The centrifuge (1) according to any one of claims 1 to 5, characterized in that a coupling element is arranged on a free end of the displacement rod located in the rotor space (9), the coupling element being designed for reconnectable connection between the displacement rod and a reaction vessel unit (7) or a carrier unit for a reaction vessel unit (7).

7. The centrifuge (1) according to claim 6, characterized in that the coupling element comprises a latching element which can engage with a counter-latching element provided on the reaction vessel unit (7) or on the carrier unit, wherein at least the latching element or the counter-latching element is elastically mounted, and / or the displacement rod is hollow and formed so as to be open at the rear end pointing away from the rotor space (9), and a threaded rod is provided coaxially with the displacement rod, and the threaded rod is in meshing engagement with a thread connected to the displacement rod, so that a translational movement of the displacement rod is carried out by a rotational movement of the threaded rod, wherein the threaded rod can enter the displacement rod at the rear end.

8. The centrifuge (1) according to any of the preceding claims, characterized in that a detection device is provided to determine the position of the displacement rod in the direction of movement and / or characterized by a pipetting unit, the pipetting unit preferably comprising a plurality of pipetting nozzles.

9. The centrifuge (1) according to any one of claims 1 to 8, characterized by an optical detection unit, the optical detection unit preferably being designed and arranged in such a way that it can scan the reaction vessel unit (7) in the area of movement of the latter, adjacent to the rotor space (9).

10. The centrifuge (1) according to claim 9, characterized in that the detection unit comprises a line camera in order to scan a reaction vessel unit line by line, a scanning line being aligned approximately perpendicular to the direction of movement of the reaction vessel unit (7).

11. The centrifuge (1) according to claim 9 or 10, characterized in that the centrifuge (1) comprises an evaluation device by means of which the signals obtained with the optical detection device are automatically evaluated according to the following parameters: - color of the contents of at least one reaction vessel of the reaction vessel unit (7), - filling level of at least one reaction vessel of the reaction vessel unit (7), - position of the reaction vessel unit (7), - type of the reaction vessel unit (7).

12. A method of cleaning a reaction vessel unit (7) comprising a centrifuge (1) according to any one of claims 1 to 11 comprising a rotor (2), wherein the reaction vessel unit (7) is arranged in the rotor (2) with the openings of the reaction vessels pointing radially outwards, the rotor (2) together with the reaction vessel unit (7) is rotated about an axis of rotation (5) so that the content of the reaction vessels is centrifuged and driven into the channel (22) and from there towards outside solely by the rotational movement of the rotor (2) and by gravity.

13. The method of cleaning a reaction vessel unit (7) comprising a centrifuge (1) comprising a rotor (2), according to claim 12, wherein the reaction vessel unit (7) is arranged in the rotor (2) with the openings of the reaction vessels pointing radially outwards, the rotor (2) together with the reaction vessel unit (7) is rotated about an axis of rotation (5) so that the content of the reaction vessels is centrifuged, wherein an exchange module (32) comprising a housing portion and the rotor (2), after cleaning one or more reaction vessel units (7), is separated from the remaining part of the centrifuge (1) and either cleaned or replaced by another exchange module (32).