Centrifuge and method for cleaning a centrifuge

Abstract

The invention relates to a centrifuge for cleaning a reaction vessel unit and a method for cleaning such a centrifuge. The centrifuge has a rotor and a rotor chamber in which the rotor is arranged and rotatably mounted, the rotor having a receiving area for receiving the reaction vessel unit. The rotor chamber is bounded by a housing, the housing having a drain for removing liquid discharged from the reaction vessels and an inlet for filling the rotor chamber with a cleaning solution such that, when the rotor rotates, it is at least partially immersed in the cleaning solution and the solution is distributed within the rotor chamber, and / or the inlet is designed such that the cleaning solution is distributed within the rotor chamber when fed in by the rotating rotor.

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 containing detergents, 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] WO 2018 / 234420 A1 discloses another centrifuge for cleaning reaction vessel units. This centrifuge has a rotor and a rotor chamber in which the rotor is rotatably mounted. A reaction vessel unit is inserted into the centrifuge with its openings facing outwards, so that the reagents contained therein are expelled from the respective reaction vessels when the rotor rotates. This allows the reaction vessels to be cleaned essentially residue-free. This centrifuge can have a dispensing unit, wherein the dispensing unit has a plurality of dispensing nozzles. The dispensing nozzles are preferably arranged adjacent to one another along a line, wherein this line extends transversely to the direction of movement of the reaction vessel unit during loading or unloading of the centrifuge. The nozzles of the dispensing unit are arranged adjacent to an opening for loading and unloading the centrifuge with the reaction vessel unit.

[0006] WO2017 / 125598 A1 discloses yet another centrifuge which again has a loading and unloading device in which reaction vessel units are positioned by means of a rigid displacement rod.

[0007] 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.

[0008] US 4,953,575 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.

[0009] 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.

[0010] JP 2007 / 178355 A discloses a system for cleaning printed circuit boards, in which one or more microtiter plates are placed in a rotating unit with a vertical rotation axis. The device has several nozzles that can spray the microtiter plates with a cleaning fluid from the outside.

[0011] JP S51 439 67 U discloses a centrifuge with a vertical axis of rotation, in which it is disclosed that the rotor can be cleaned by filling water into the chamber and rotating the rotor.

[0012] CN 113 000 230 A also discloses a centrifuge with a vertical axis of rotation for the automatic cleaning of disinfectants.

[0013] The invention is based on the object of creating a centrifuge for cleaning a reaction vessel unit, which has a rotor and a rotor chamber in which the rotor is rotatably mounted, wherein the centrifuge is intended to avoid contamination and to enable reliable operation over the long term.

[0014] This object is achieved by the subject matter according to the independent patent claims. Advantageous embodiments of the invention are specified in the respective subclaims.

[0015] A centrifuge according to the invention for cleaning a reaction vessel unit has a rotor and a rotor chamber in which the rotor is arranged and mounted, wherein the rotor has a receiving area for receiving the reaction vessel unit. The rotor chamber is delimited by a housing, wherein the housing has an outlet for removing liquid discharged from the reaction vessels and is provided with an inlet for filling the rotor chamber with a cleaning solution such that the cleaning solution is distributed by rotation of the rotor without reaction vessel units in the rotor chamber through contact with the rotor, so that the rotor chamber is cleaned. The rotation axis of the rotor runs parallel to a base surface.

[0016] This centrifuge can thus be fed with a cleaning solution and distributed throughout the rotor chamber. The rotor is used to distribute the cleaning solution. This will be discussed in more detail below when explaining the centrifuge cleaning process.

[0017] As the rotor rotates, it can be at least partially immersed in the cleaning solution, distributing it throughout the rotor chamber. The inlet is designed so that the cleaning solution is distributed throughout the rotor chamber as it is fed through the rotating rotor. The cleaning solution can come into contact with the rotor and be distributed by the centrifugal forces acting on the rotor, and / or be entrained by the air flow generated by the rotor and thus distributed.

[0018] Because the rotor's rotational axis runs parallel to a supporting surface, the cleaning solution is distributed throughout the entire rotor chamber when the rotor chamber is partially filled by partially immersing the rotor in the cleaning solution. It is not necessary to completely fill the entire rotor chamber with the cleaning solution. Therefore, the rotor chamber does not need to be perfectly sealed. Furthermore, in contrast to an arrangement in which the rotor's rotational axis runs perpendicular to a supporting surface, the cleaning solution is not distributed only radially outward by centrifugal force without being distributed throughout the entire rotor chamber.

[0019] Due to the parallel alignment of the rotation axis and the immersion, the cleaning solution in the rotor chamber is carried upwards by the rotor and evenly distributed in the rotor chamber by the resulting air flow.

[0020] When cleaning a reaction vessel unit in a centrifuge, where the contents of the reaction vessels are ejected from the reaction vessels in the reaction vessel unit, there is a risk that residues of the contents of the reaction vessels may remain in the rotor chamber and possibly be transferred to another reaction vessel unit. This is particularly critical when the reaction vessel units contain chemical or biological samples. With biological samples, a single molecule, such as a section of a DNA strand, transferred to another reaction vessel unit can represent intolerable contamination.

[0021] Such centrifuges for cleaning reaction vessel units are now used with great success. However, they must be cleaned at regular intervals. The inventive design of the centrifuge allows for independent or automatic cleaning. This allows the centrifuge to be part of an automated process and to be subjected to a cleaning procedure from time to time without the need for manual intervention by an operator. For example, the centrifuge can be cleaned multiple times in a workflow lasting several hours without requiring manual intervention. This is a significant advantage over conventional centrifuges for cleaning reaction vessel units.

[0022] The housing outlet can also form the inlet. For example, an opening in the housing that forms the outlet or the inlet can be connected to a fluid line that has a branch point, so that the fluid line branches into an inlet line and a drain line. The drain line is designed to discharge a fluid, and the inlet line is designed to supply a fluid. The drain line has a blocking element for blocking the drain line. If the drain line is blocked by the blocking element, the fluid or a cleaning solution can be supplied via the inlet line without flowing out via the drain line and being supplied exclusively to the rotor chamber.

[0023] The blocking element can be a valve or a preferably automatically actuated hose clamp if at least part of the drain line is designed as a hose. The hose clamp can be provided with an actuator for automatic actuation. The actuator can be designed as an eccentric or as an electric or pneumatic piston mechanism.

[0024] The inlet line can also be fluidically coupled to a dispensing device integrated into the centrifuge, so that a cleaning solution can be supplied to the inlet line via the dispensing device. In such a centrifuge embodiment, the dispensing device functions both to dispense solutions into reaction vessels of the reaction vessel units and to supply the cleaning solution to the rotor chamber.

[0025] The drain can be provided with a suction pump and a siphon, wherein the siphon is designed such that when the suction pump is not actuated, a liquid with a fill level below a predetermined fill level remains in the rotor chamber. By not actuating the suction pump, it can be ensured that any cleaning solution present in the rotor chamber remains in the rotor chamber, provided the fill level of the cleaning solution is not above the predetermined fill level. The level of this predetermined fill level is preferably selected such that a rotor is immersed in the liquid when rotating and at least partially carries it away. The siphon thus forms the blocking element with which the drain line is blocked up to a certain fill level, provided the suction pump is not actuated.

[0026] A level sensor can be provided in the rotor chamber to detect the liquid level. The level sensor can be an ultrasonic sensor that scans the surface of the liquid. It is advisable to rotate the rotor to a position where it does not interfere with the measurement. The level can also be provided by one or more temperature sensors mounted on the inner surface of the housing and used to measure a specific liquid level.

[0027] The inlet can be arranged above a rotational axis of the rotor so that when the cleaning solution is fed in, the cleaning solution can come into contact with the rotor. The rotor can of course be in a position where it does not come into contact with the cleaning solution fed in via the inlet, e.g. if it is aligned vertically. As a result, a cleaning liquid fed in in this way is entrained by a rotating, particularly fast-rotating rotor and distributed in the rotor chamber. Low speeds of just a few rpm are sufficient for this. As a rule, the rotor is rotated at speeds of at least 10 rpm or at least 50 rpm or more. The rotor should not rotate faster than 100 rpm if the cleaning solution has been introduced into the rotor chamber up to a predetermined level so that the rotor can be immersed in the cleaning solution. If, on the other hand, the cleaning solution is in the rotor chamber, e.g.If the cleaning solution is introduced by atomization without accumulating at the bottom of the rotor chamber, the rotor can also be operated at higher speeds of, for example, at least 100 rpm. In this case, speeds of at least 500 rpm or at least 1000 rpm may also be appropriate.

[0028] The inlet can also have one or more nozzles to atomize the cleaning solution into the rotor chamber. The cleaning fluid atomized in this way can also be evenly distributed throughout the rotor chamber by rotating the rotor.

[0029] A further aspect of the invention relates to a method for cleaning a centrifuge for cleaning a reaction vessel unit, wherein the centrifuge comprises 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 wherein the rotational axis of the rotor runs parallel to a base. In this method, the following steps are performed: The rotor chamber is filled with a cleaning liquid either at least to a predetermined level so that when the rotor rotates it is at least partially immersed in the cleaning solution, and / or the cleaning solution is supplied to the rotor chamber in such a way that it can either come into contact with the rotor and / or is introduced into an area of ​​the rotor chamber in which it is carried along by an air stream when the rotor rotates, the rotor is rotated / moved, whereby the cleaning solution is distributed in the rotor chamber, and the cleaning solution is removed from the rotor chamber.

[0030] When the cleaning solution is removed, the contaminants in the rotor chamber are removed. The cleaning solution can flow out via the drain and thus be removed from the rotor chamber. This can be controlled, for example, by opening a blocking element in a drain line.

[0031] The rotor in such a centrifuge has two functions. Firstly, the rotor serves to empty the reaction vessel units by spinning the contents out of the individual reaction vessels of the reaction vessel units as the rotor rotates. Secondly, the rotor also serves to distribute the cleaning solution in the rotor chamber, thus ensuring even and reliable cleaning of the rotor chamber. The cleaning solution can be distributed by the rotor being at least partially immersed in the cleaning solution as it rotates, thus carrying it along. However, the cleaning solution can also be supplied in such a way that it is carried directly by the rotor or by the airflow generated by the rotor and distributed in the rotor chamber. This is particularly true if the cleaning solution is atomized into the rotor chamber; in this case, a mist of the cleaning solution is evenly distributed throughout the rotor chamber by rotating the rotor.

[0032] The cleaning solution can be a non-foaming cleaning solution containing, for example, formaldehyde or paraformaldehyde. Such a non-foaming cleaning solution can drain from the rotor chamber independently, without any further action. The rotation of the rotor can drive the cleaning solution to the drain and remove it from the rotor chamber. However, the cleaning solution can also drain automatically when the rotor is stationary, provided the drain line is appropriately unblocked.

[0033] The cleaning solution can also be a foaming cleaning solution, especially one containing surfactants. As the cleaning solution is distributed through the rotor, it foams in the rotor chamber. To remove the foamed cleaning solution, a foam-decomposing solution, such as one containing alcohol, can be added to the rotor chamber. This causes the foam to collapse and flow out through the drain. The drainage or removal of the cleaning solution from the rotor chamber can also be assisted by rotating the rotor, just as with the non-foaming cleaning solution.

[0034] The foam-reducing solution can also be distributed in the rotor chamber during or after feeding by rotating the rotor in order to effectively distribute the foam-reducing solution in the rotor chamber.

[0035] In this process, a centrifuge as described above can be used.

[0036] The invention is explained in more detail below by way of example with reference to the drawings. The drawings show: Figure 1 a part of a centrifuge housing in perspective view, Figure 2 the part of the housing made of Figure 1 in a sectional view looking obliquely from the front, Figure 3 the part of the housing made of Figure 1 in a longitudinal section, Figure 4a the centrifuge according to a first embodiment with the housing part made of Figure 1 in a longitudinal section, and Figure 4b the centrifuge according to a second embodiment with the housing part made of Figure 1 in a longitudinal section.

[0037] A centrifuge 1 according to the invention ( Figure 4a ) has a rotor 2, a housing 3, a drive device 4 for rotating the rotor 2 about a rotation axis 5.

[0038] 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 vessel unit 7. Such a reaction vessel unit 7 can be inserted into a receiving area 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] Adjacent to this door 20, a dispensing unit 39 with several dispensing nozzles 40 and / or an optical detection unit, in particular in the form of a line scan camera, can be provided.

[0044] 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.

[0045] 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.

[0046] 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 4a ). 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.

[0047] 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.

[0048] 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.

[0049] 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, but only has a cylindrical curvature 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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 groove 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 groove can no longer be driven back into the rotor chamber. In principle, a groove with an approximately vertical side wall on the side of the groove 22 downstream of the direction of rotation 38 is sufficient. However, from a manufacturing perspective, it is expedient to produce a groove with two approximately vertical side walls 37a, 37b.

[0054] This design of the funnel 26 and the channel 22 eliminates the need for a suction pump.

[0055] The dispensing unit 30, which can also be referred to as a dispensing head, has several dispensing nozzles 31 arranged along a straight line with their openings pointing downward. The dispensing unit 30 is connected to a reagent line 32, via which reagents are supplied to the dispensing unit 30, which are then distributed downward via the individual dispensing nozzles 31. The dispensing unit basically has the function known from WO 2018 / 234420 A1, namely that reaction vessels of a reaction vessel unit 7 can be filled with reagents when the reaction vessel unit 7 is moved past the dispensing unit 30 by means of the loading and unloading device 8.

[0056] In the first embodiment of the present invention ( Figure 4a) the balcony 18 is formed in the area below the dispensing unit 30 with an upwardly open groove 33 in which the reagents dispensed by the dispensing nozzles 31 are collected if no reaction vessel unit 7 is arranged below the dispensing nozzles 31, as shown in Figure 4ais shown. The channel 33 is connected in a communicating manner to a collecting tube 34 so that the reagents collected in the channel 33 flow away via the collecting tube 34. The collecting tube 34 opens into the tube 25 at a branch 35. With regard to the rotor chamber 9, starting from the branch 35, the collecting tube forms an inlet line and the tube 25 forms an outlet line for discharging liquids from the rotor chamber 9. A blocking element 36 is arranged in the tube 25 downstream of the branch 35, with which blocking element the passage of the tube 25 can be blocked. The blocking element 36 can be a preferably electrically actuated valve in order to open or close the passage of the tube. The blocking element can also be a hose clamp, which can be opened or closed, for example, with an actuator or by means of an eccentric.

[0057] If the blocking element 36 blocks the passage of the hose 25 and a cleaning solution is supplied via the collection hose 34 with the dispensing unit 30, the cleaning solution flows via the hose 25 and the outlet opening 23 into the rotor chamber 9. The outlet opening 23 then serves as the inlet for the cleaning solution. In principle, it would be possible to supply cleaning solution to the rotor chamber 9 up to the level of the top of the balcony 18. However, it is advisable not to flood the ball bearings 14 of the shaft 15 with cleaning solution. The rotor chamber 9 is filled above the level 29 ( Figure 2 ) is filled with cleaning solution, so that when the rotor 2 rotates, it is immersed in the cleaning solution and takes part of the cleaning solution with it and distributes it in the rotor chamber 9. In practice, it has been shown that the rotor chamber 9 is filled at least up to a level 43, as Figure 2is shown. The level 43 is approximately 5% of the radius of the rotor 2 and preferably at least 10% of the radius of the rotor 2 above the level 29, which is just not touched during rotation of the rotor 2.

[0058] By rotating the rotor 2, the cleaning solution is distributed in the rotor chamber 9 so that all parts of the rotor chamber 9 come into contact with the cleaning solution.

[0059] While the cleaning solution is being distributed by rotating the rotor 2, cleaning solution can continue to be supplied via the dispensing unit 30 in order to slow down or prevent the level of the cleaning solution from dropping.

[0060] Once the cleaning solution is sufficiently distributed in the rotor chamber 9, a predetermined period of time can be allowed to elapse so that the cleaning solution can absorb the contaminants. During this time, the rotation of the rotor can be adjusted, or the rotor can be rotated further to ensure continuous swirling of the cleaning solution in the rotor chamber through the airflow.

[0061] Once this cleaning step is complete, the blocking element 36 is opened, allowing the cleaning solution to flow through the outlet opening 23. This can be assisted by further rotation of the rotor, forcing the cleaning solution into the channel 22.

[0062] This cleaning process of the rotor chamber 9 can be carried out fully automatically and is controlled by the central control device.

[0063] A non-foaming cleaning solution, such as formaldehyde or paraformaldehyde, is preferably used as the cleaning solution, with which the entire rotor chamber 9 can be reliably disinfected.

[0064] However, for biological samples, particularly samples containing bacteria, it is advantageous if the cleaning solution contains surfactants, which cause the cleaning solution to foam when the rotor rotates. Foaming of the cleaning solution causes a very rapid and even distribution of the cleaning solution in the rotor chamber 9, which is why the rotational speed and / or duration at which the rotor is rotated in the rotor chamber 9 can and should be significantly reduced compared to distributing non-foaming cleaning solution. In order to completely remove the foamed cleaning solution from the rotor chamber 9, a foam-decomposing solution is fed to the rotor chamber 9 via the dispensing unit 30 and the collection hose 34 and distributed by rotating the rotor 2. As a result, the foam in the rotor chamber 9 collapses, and the cleaning solution flows out of the rotor chamber 9 together with the foam-decomposing solution.Such a foam-reducing solution can contain alcohol, for example. An alcohol-containing solution also has the advantage that it evaporates very quickly, thus drying the rotor chamber 9 accordingly quickly.

[0065] A second embodiment of the centrifuge 1 ( Figure 4b) is designed essentially in the same way as the first exemplary embodiment, unless explained otherwise below, which is why identical parts are provided with the same reference numerals and are not explained again. The second exemplary embodiment does not have to have a dispensing unit. On the rear end wall 13, in the area above the shaft 15, there is a feed opening 39 which is connected to the reagent line 32 and opens into the rotor chamber 9. In the present exemplary embodiment, an atomizing nozzle 40 is arranged in the feed opening 39, with which reagents supplied via the reagent line 32 are atomized into the rotor chamber 9. By supplying a cleaning solution via the feed opening 39, this is introduced into the rotor chamber 9 and atomized by the atomizing nozzle 40 into a mist, which is distributed evenly in the rotor chamber 9 by rotation of the rotor 2.A portion of the cleaning solution settles in the channel 22 and drains out of the rotor chamber 9 via the outlet opening 23 and the hose 25. This allows the cleaning solution to be continuously circulated and removed in the rotor chamber 9 to remove contaminants from the rotor chamber 9. A blocking element 36 can optionally be provided in the hose 25 to block the passage of the hose 25 and retain the cleaning solution in the rotor chamber 9.

[0066] It may also be useful to rotate the rotor alternately in different directions during the cleaning process in order to achieve the most even distribution of the cleaning solution in the rotor chamber.

[0067] In principle, it is also possible not to arrange an atomizing nozzle 40 in the supply opening 39. This depends on the dimensions of the rotor chamber, the rotor, and the air flow generated thereby during rotation of the rotor. Thus, sufficient distribution of the cleaning solution can be achieved simply by rotating the rotor and the air flow generated thereby, without the need for atomizing nozzles. On the other hand, it may also be expedient to provide several supply openings 39, particularly on the upper shell 11, in order to achieve uniform distribution across the entire width of the rotor chamber 9 in the direction of the rotation axis 5.

[0068] A pressure nozzle can also be inserted into the feed opening(s) 39. A pressure nozzle is a nozzle that opens when the cleaning solution is fed to the nozzle at a predetermined pressure. This allows the timing of the cleaning solution feed into the rotor chamber to be precisely controlled. The pressure nozzle can also be an atomizing nozzle.

[0069] Furthermore, in the second embodiment, if the blocking element 36 is provided in the hose 25, as much cleaning solution can be introduced into the rotor chamber 9 via the feed opening 39 until a filling level corresponding to the level 43 of Figure 2 is achieved. Then, by rotating the rotor, as explained above with reference to the first embodiment, the cleaning solution can be evenly distributed in the rotor chamber 9.

[0070] Furthermore, the second embodiment can be modified in that the hose 25 is formed into a siphon 41 ( Figure 4b), i.e. the hose 25 is guided upwards a short distance from the outlet opening 23 and is then deflected downwards so that liquid flowing into the hose 25 only overcomes the siphon when the liquid level in the rotor chamber 9 has reached the height of the siphon. With such an arrangement of the hose 25, either a suction pump 42 must be provided in the hose 25 in order to completely suck the liquid out of the rotor chamber 9 via the siphon 41 if necessary, or a lifting mechanism can be provided which lowers the hose 25 in such a way that the siphon 41 is lifted and the liquid contained in the hose 25 flows out due to gravity alone.

[0071] In the second embodiment, non-foaming cleaning solutions or foaming cleaning solutions can also be supplied. If foaming cleaning solutions are used, it is expedient, just as in the first embodiment, to supply a foam-degrading solution to the rotor chamber 9 in order to remove the foaming cleaning solution from the rotor chamber 9.

[0072] The above embodiments and modifications show that the cleaning solution or solutions can be supplied to or removed from the rotor chamber 9 in different ways in order to clean the rotor chamber 9. Common to all embodiments and variants is that the rotor 2, which is inherently present in the centrifuge 1, is used to evenly distribute the cleaning solution in the rotor chamber 9. The rotational speed and the duration at which the rotor 2 is rotated must be adapted to the geometry of the rotor interior 9 and the behavior of the cleaning solution. In this case, it can be particularly expedient (regardless of the structural design of the centrifuge) to rotate the rotor 2 at least once clockwise and at least once counterclockwise in order to achieve the most even distribution of the cleaning solution in the rotor chamber 9.If one or more atomizing nozzles 40 are used, it is expedient to supply the cleaning solution under pressure so that the atomizing nozzles 40 effect efficient atomization of the cleaning solution.

[0073] The supply and even distribution as well as the removal of the cleaning solution from the rotor chamber 9 can be carried out fully automatically. This allows the centrifuge 1 to be used in an automated production process in which many reaction vessel units 7 are repeatedly cleaned, permanently ensuring that no contamination occurs from one reaction vessel unit 7 to another. The intervals between the cleaning processes of the rotor chamber 9 must be adapted to the quantity and reactivity of the reagents contained in the reaction vessel units 7. Such a cleaning process can, for example, be carried out at intervals of no more than 10 minutes or no more than 60 minutes. However, with less reactive reagents and small quantities, it may also be expedient to perform such a cleaning process only once a day.

[0074] The cleaning process can be used to completely disinfect the interior and reliably prevent contamination by viruses, bacteria or other infectious agents.

[0075] Furthermore, for DNA-containing samples, agents can be used as solvents that destroy nucleic acids and thus eliminate contamination. These agents include perchlorate, strong oxidizing agents, and / or enzymes such as DNAse.

[0076] If an unforeseen contamination of the rotor chamber 9 occurs, such as a reaction vessel unit 7 bursting during centrifugation, the system can be completely cleaned without having to open the interior or the device.

[0077] The invention can be briefly summarized as follows: The invention relates to a centrifuge 1 for cleaning a reaction vessel unit 7 and to a method for cleaning such a centrifuge 1. The centrifuge 1 has a rotor 2 and a rotor chamber 9 in which the rotor 2 is arranged and rotatably mounted, wherein the rotor 2 has a receiving area 6 for receiving the reaction vessel unit 7. The rotor chamber 9 is delimited by a housing 3, wherein the housing 3 has an outlet for removing liquid discharged from the reaction vessels and is provided with an inlet for filling the rotor chamber 9 with a cleaning solution in such a way that when the rotor 2 rotates, it is at least partially immersed in the cleaning solution and distributes this in the rotor chamber 9 and / or the inlet is designed such that the cleaning solution is distributed in the rotor chamber 9 when fed in by the rotating rotor 2.

[0078] The following are examples of the use of the centrifuge according to the invention. 1. A method for cleaning a centrifuge (1) for cleaning a reaction vessel unit (7), wherein the centrifuge (1) has a rotor (2) and a rotor chamber (9) in which the rotor (2) is arranged and rotatably mounted, wherein the rotor (2) has a receiving area (6) for receiving the reaction vessel unit (7), wherein the rotation axis (5) of the rotor (2) runs parallel to a base (16), and the following steps are carried out: the rotor chamber (9) is filled with a cleaning solution either at least to a predetermined level (43) so that when the rotor (2) rotates, it is at least partially immersed in the cleaning solution, and / or the cleaning solution is fed to the rotor chamber (9) such that it can either come into contact with the rotor (2) and / or is atomized into the rotor chamber (9), the rotor (2) is rotated, whereby the cleaning solution is distributed in the rotor chamber (9), and the cleaning solution is removed from the rotor chamber (9). 2.Method according to example 1, characterized in that the cleaning solution is a non-foaming cleaning solution which contains, for example, formaldehyde or paraformaldehyde. 3. Method according to example 2, characterized in that the cleaning solution is a foaming cleaning solution, in particular a cleaning solution containing surfactants, and in order to remove the cleaning solution, a foam-decomposing solution which contains, for example, alcohol is fed to the rotor chamber (9). 4. Method according to example 3, characterized in that during or after the feeding of the foam-decomposing solution, the rotor (2) is rotated in order to distribute the foam-decomposing solution in the rotor chamber (9). 5. Method according to one of examples 1 to 4, characterized in that a centrifuge (1) according to claims 1 to 8 is used. Reference symbol list

[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 Dispensing unit 31 Dispensing nozzle 32 Reagent line 33 Trough 34Collecting hose 35Branching 36Locking element 37aSide wall 37bSide wall 38Direction of rotation 39Feed opening 40Amp nozzle 41Siphon 42Suction pump 43Level

Claims

1. Centrifuge (1) for cleaning a reaction vessel unit (7) with a rotor (2) and a rotor chamber (9) in which the rotor (2) is arranged and rotatably mounted, wherein the rotor (2) has a receiving area (6) for receiving the reaction vessel unit (7), and the rotor chamber (9) is delimited by a housing (3), wherein the housing (3) has an outlet for removing liquid discharged from the reaction vessels and is provided with an inlet for supplying the rotor chamber (9) with a cleaning solution such that the cleaning solution is distributed by rotating the rotor (2) without reaction vessel units (7) in the rotor chamber (9) through contact with the rotor (2), so that the rotor chamber (9) is cleaned, wherein the rotation axis (5) of the rotor (2) runs parallel to a base (16), and wherein the centrifuge has a control device designed such thatthat - the rotor chamber (9) is filled with a cleaning solution at least to a level (43) such that when the rotor (2) rotates, it is at least partially immersed in the cleaning solution, - rotating the rotor (2), whereby the cleaning solution is distributed in the rotor chamber (9), and - removing the cleaning solution from the rotor chamber (9)., 2. Centrifuge (1) according to claim 1, characterized by that the outlet of the housing (3) also forms the inlet.

3. Centrifuge (1) according to claim 2, characterized by that an opening in the housing (3), which forms the outlet and the inlet, is connected to a fluid line which has a branch point and branches into an inlet line and a drain line, wherein the drain line is designed to discharge a fluid and the inlet line is designed to supply a fluid, and the drain line has a blocking element (36) for blocking the drain line.

4. Centrifuge (1) according to claim 3, characterized by that the inlet line is fluidically coupled to a dispensing device integrated in the centrifuge (1), so that a cleaning solution can be supplied to the inlet line by means of the dispensing device.

5. Centrifuge (1) according to one of claims 1 to 4, characterized by that the outlet comprises a suction pump and a siphon (41), wherein the siphon (41) is designed such that when the suction pump is not actuated, a liquid with a filling level below a predetermined filling level remains in the rotor chamber (9).

6. Centrifuge (1) according to one of claims 1 to 5, characterized by that a fill level sensor is provided for detecting the fill level in the rotor chamber (9).

7. Centrifuge (1) according to one of claims 1 to 6, characterized by that the inlet is arranged above a rotational axis of the rotor (2) so that when the cleaning solution is supplied, it can come into contact with the rotor (2).

8. Centrifuge (1) according to one of claims 1 to 7, characterized by that the inlet has one or more nozzles to atomize the cleaning solution into the rotor chamber (9).

9. Centrifuge (1) according to one of claims 1 to 8, characterized by that the rotor chamber (9) is filled with the cleaning solution up to a predetermined level, and that the rotor (2) is designed so that when rotating it is at least partially immersed in the cleaning solution and distributes it in the rotor chamber (9).

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