MIXING DEVICE AND A SINGLE-USE DEVICE FOR A MIXING DEVICE
20240253000 ยท 2024-08-01
Inventors
Cpc classification
B01F2101/44
PERFORMING OPERATIONS; TRANSPORTING
B01F33/453
PERFORMING OPERATIONS; TRANSPORTING
B01F35/511
PERFORMING OPERATIONS; TRANSPORTING
B01F35/3213
PERFORMING OPERATIONS; TRANSPORTING
B01F35/513
PERFORMING OPERATIONS; TRANSPORTING
B01F2215/0422
PERFORMING OPERATIONS; TRANSPORTING
B01F27/808
PERFORMING OPERATIONS; TRANSPORTING
International classification
B01F35/513
PERFORMING OPERATIONS; TRANSPORTING
B01F35/511
PERFORMING OPERATIONS; TRANSPORTING
B01F33/453
PERFORMING OPERATIONS; TRANSPORTING
B01F27/808
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A mixing device for mixing at least two substances includes a single-use device and a reusable device. The single-use device includes an impeller, vanes, and a cup for receiving the rotor housing. A magnetically effective core is in the rotor housing. The reusable device includes a stator to contactlessly magnetically drive the impeller about the axis of rotation and magnetically levitate the impeller with respect to the stator. A plurality of stabilizing elements is on the impeller for stabilizing the impeller against tilting. Each stabilizing element is arranged between two vanes and extends from a radial inner edge to a radial outer edge with respect to the radial direction, and each radial outer edge has a distance from the axis of rotation which is smaller than half the outer diameter of the impeller.
Claims
1. A mixing device for mixing at least two substances, comprising: a single-use device configured for single use; and a reusable device configured for multiple use, the single-use device comprising an impeller having a rotor housing and a plurality of vanes to mix the substances, and a cup to receive the rotor housing, the impeller configured to rotate about a desired axis of rotation defining an axial direction, the impeller having an outer diameter which is a maximum extension of the impeller in a radial direction perpendicular to the axial direction, a magnetically effective core disposed in the rotor housing, the cup configured in a dimensionally stable manner, the reusable device comprising a stator, by which, in the operating state, the impeller is capable of being contactlessly magnetically driven to rotate about the desired axis of rotation and magnetically levitated with respect to the stator, the stator comprising a plurality of windings to generate an electromagnetic rotating field to drive and levitate the impeller, and the stator having a stator housing with a recess configured to receive the cup with the rotor housing arranged therein, so that the cup is capable of being inserted into the recess, a plurality of stabilizing elements disposed at the impeller to stabilize the impeller against tilting, each stabilizing element of the plurality of stabilizing elements arranged between two vanes of the plurality of vanes and extending from a radial inner edge to a radial outer edge with respect to the radial direction, and each of the radial outer edges having a distance from the desired axis of rotation which is smaller than half the outer diameter of the impeller.
2. The mixing device according to claim 1, wherein each vane of the plurality of vanes is arranged with a radial distance from the desired axis of rotation with respect to the radial direction, the radial distance being different from zero, and the radial inner edge of each stabilizing element of the plurality of stabilizing elements has a distance from the desired axis of rotation which is greater than the radial distance.
3. The mixing device according to claim 1, wherein each vane of the plurality of vanes has a front side, a back side, an upper edge and a lower edge, the front side preceding the back side when the impeller rotates, for each vane of the plurality of vanes the lower edge and the upper edge delimit the vane with respect to the axial direction, the upper edge arranged at an end of the vane facing away from the rotor housing, and for each vane of the plurality of vanes, a stabilizing element of the plurality of stabilizing elements is arranged on the front side or on the back side of the vane.
4. The mixing device according to claim 3, wherein each stabilizing element of the plurality of stabilizing elements enclose an angle different from 0? and from 180? with the front side or with the back side of a respective vane.
5. The mixing device according to claim 3, wherein the plurality of stabilizing elements are arranged symmetrically, such that for each vane of the plurality of vanes, on the front side of which the stabilizing element of the plurality of stabilizing elements is disposed, another stabilizing element of the plurality of stabilizing elements is disposed on the back side.
6. The mixing device according to claim 3, wherein, for a respective vane, the stabilizing element of the plurality of stabilizing elements is arranged closer to the lower edge than to the upper edge.
7. The mixing device according to claim 3, wherein each vane of the plurality of vanes is designed in a curved manner so that the front side or the back side is concaved.
8. The mixing device according to claim 3, wherein the plurality of stabilizing elements comprise ring segments which each ring segment extending from the front side of a respective vane of the plurality of vanes to the back side of an adjacent vane of the plurality of vanes.
9. The mixing device according to claim 1, wherein the rotor housing is cylindrical with an outer housing diameter, and with an upper end face and with a lower end face, which delimit the rotor housing with respect to the axial direction, and on which the plurality of vanes are provided.
10. The mixing device according to claim 9, wherein the plurality of stabilizing elements are arranged on the upper end face of the rotor housing, and a distance of each radial outer edge from the desired axis of rotation is greater than half the housing diameter of the rotor housing.
11. The mixing device according to claim 9, wherein the upper end face or the lower end face of the rotor housing includes a chamfer which extends along an entire circumference of the end face.
12. The mixing device according to claim 1, further comprising at least one relief boreextending completely through the impeller in the axial direction.
13. A single-use device for a mixing device according to claim 1, wherein the single-use device comprises the impeller and the cup to receive the rotor housing.
14. The single-use device according to claim 13, further comprising a fixing device configured to magnetically retain the magnetically effective core in the cup, and the fixing device is configured to be removed by pulling.
15. The single-use device according to claim 13, further comprising a flexible mixing container for the substances to be mixed, the mixing container is sealingly connected to the cup to form an entirety, and the impeller is arranged in the entirety.
16. The mixing device according to claim 3, wherein each stabilizing element of the plurality of stabilizing elements enclose an angle in the range from 40? to 140? with the front side or with the back side of a respective vane.
17. The mixing device according to claim 1, wherein the rotor housing is cylindrical with an outer housing diameter, and with an upper end face and with a lower end face, which delimit the rotor housing with respect to the axial direction, a disk-shaped hub disk is arranged on the upper end face of the rotor housing, on which the plurality of vanes are provided.
18. The mixing device according to claim 17, wherein the plurality of stabilizing elements are arranged on the hub disk, and a distance of each radial outer edge from the desired axis of rotation is greater than half the housing diameter of the rotor housing.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] In the following, embodiments of the invention will be explained in more detail with reference to the drawings
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DETAILED DESCRIPTION
[0051]
[0052] In order to guarantee the purity or sterility of those components which come into contact with the substances to be mixed, the mixing device 1 according to the disclosure comprises a single-use device, which is designated in its entirety by the reference sign 100 and which is designed for single use, as well as a reusable device, which is designated in its entirety by the reference sign 200 and which is designed for permanent use, i.e. for multiple use. The single-use device 100 preferably comprises those components which come into contact with the substances to be mixed during the mixing process.
[0053] The term single-use device and other compositions with the component single-use, such as single-use part, single-use component, etc., refer to those devices, components or parts which are designed for single-use, i.e., which can be used only once as intended and are then disposed of. For a new application, a new, previously unused single-use part must then be used. When configuring or designing the single-use device 100, substantial aspects are therefore that the single-use device 100 can be produced as simply and economically as possible, generate few costs and can be produced from materials that are available at the lowest possible price. It is another substantial aspect that the single-use device 100 can be assembled as easily as possible with the reusable device. The single-use device 100 should therefore be able to be replaced very easily without the need for high assembly effort. Particularly preferably, the single-use device 100 should be able to be assembled with the reusable device 200 or separated from the reusable device 200 without the use of tools.
[0054] For a better understanding,
[0055] In the mixing device 1 (
[0056] The rotor housing 2 is designed cylindrically with an outer housing diameter DR. The rotor housing 2 has an upper end face 25 and a lower end face 26, which delimit the rotor housing 2 with respect to the axial direction A. In the embodiment described here, the five vanes 7 are arranged directly on the upper end face 25 of the rotor housing 2, wherein the vanes 7 are arranged equidistantly on the upper end face 25 with respect to the circumferential direction. For example, the vanes 7 can be placed on the upper end face 25 and attached there, for example by a clamp connection or a snap-lock connection, or the vanes 7 are glued or welded to the upper end face 25. It is also possible that the vanes 7 are an integral part of the rotor housing 2.
[0057] According to an also preferred variant (see
[0058] The impeller 10 with the rotor housing 2 is designed for rotating about a desired axis of rotation D, which defines the axial direction A, wherein the impeller 10 can be contactlessly magnetically driven and can be magnetically levitated. For this purpose, the magnetically effective core 3 is arranged in the rotor housing 2. The magnetically effective core 3 of the impeller 10 refers to that area of the impeller 10 which cooperates magnetically with a stator 4 for torque formation and for generating the magnetic levitating forces.
[0059] The impeller 10 has an outer diameter DA (
[0060] The cup 81 is designed in a dimensionally stable manner and is preferably made of a plastic. The cup 81 is designed substantially cylindrically and rotationally symmetrical with respect to the axial direction A.
[0061] The inner diameter of the cup 81 is dimensioned such that it is slightly larger than the housing diameter DR of the rotor housing 2. Here, slightly is to be understood in the sense that, on the one hand, the rotor housing 2 can rotate freely in the cup 81 without touching the inner wall of the cup 81 and, on the other hand, the distance between the cylindrical outer wall of the rotor housing 2 and the inner wall of the cup 81 is as small as possible in order to ensure an efficient magnetic levitation and an efficient magnetic drive of the impeller 10.
[0062] The reusable device 200 comprises the stator 4, with which the impeller in the operating state can be contactlessly magnetically driven for rotation about the desired axis of rotation D and can be magnetically levitated with respect to the stator 4, wherein the stator 4 comprises a plurality of windings 6 (see, for example,
[0063] The stator housing 5 is delimited with respect to the axial direction A by two end faces. A central recess 51 is disposed in one of the two end faces, which is designed for receiving the cup 81 with the rotor housing 2 arranged therein, so that the cup 81 can be inserted into the recess 51. Thus, the magnetically effective core 3 arranged in the rotor housing 2 can interact magnetically with the stator 4 and be driven for rotation without contact by the windings 6 of the stator 4. The recess 51 in the stator housing 5 is designed with respect to its radial dimension in such a way that, on the one hand, the cup 81 can be inserted into the recess 51 in a simple manner and that, on the other hand, the distance between the stator housing 5 and the magnetically effective core 3 measured in the radial direction is as small as possible. The dimensions of the cup 81 and the recess 51 are preferably adapted to each other in such a way that the recess 51 closely encloses the cup 81 in the assembled state and abuts with its wall against the shell surface of the cup 81.
[0064] Preferably, the single-use device 100 further comprises a flexible mixing container 110 for receiving the substances to be mixed, which is made of a plastic. The flexible mixing container 110 is indicated in
[0065] The mixing container 110 can have at least one inlet (not represented) in a manner known per se through which the substances to be mixed can be introduced into the mixing container 110. Furthermore, further inlets can be provided, for example for feeding additional substances, for accommodating probes or measuring sensors with which parameters are monitored during the mixing process, e.g., temperature, pressure, concentrations, etc. The inlets can also be used for mass transfer, in particular during the mixing process. In particular, necessary gases can be fed or discharged here, for example in an embodiment as a bioreactor. In particular in the cultivation of microorganisms or biological tissue or cells, it is often a necessity that oxygen or air can be fed to the mixing container 110 and other gases, in particular carbon dioxide, can be discharged from the mixing container 110. Furthermore, the mixing container 110 comprises at least one outlet (not represented) through which substances, for example the mixed substances, can be discharged.
[0066] Since the flexible mixing container 110 is often adapted to the specific application, for example with respect to the number and arrangement of the inlets, it is a preferred variant that the single-use device 100 is packaged and delivered to the user without the flexible mixing container 110. The user then provides the flexible mixing container 110 suitable for the specific application and sealingly connects it to the cup 81 of the single-use device 100 to form the entirety for receiving the substances to be mixed.
[0067] For use, the flexible mixing container 110 with the cup 81 attached thereto is inserted into a dimensionally stable support container 210, which is, for example, a component of the reusable device 200. The support container 210 is designed substantially cylindrically with a circular bottom plate 211 and a cylindrical side wall 212. The side wall 212 is indicated in
[0068] The substantially cylindrically designed supporting container 210 is open on its upper side, so that the mixing container 110 can be inserted into the support container 210 without difficulty. The support container 210 is designed, for example, as a tank and is made, for example, of steel, in particular a stainless steel.
[0069] A centrally arranged and circularly designed opening 213 is disposed in the bottom plate 211 of the support container 210, which opening 213 is dimensioned such that the cup 81 can be passed through this opening 213 and is supported at its edge by the bottom plate 211.
[0070] The stator housing 5 is arranged on the outside of the bottom plate 211 such that the central recess 51 in the stator housing 5 is aligned with the opening 213 in the bottom plate 211, so that the cup 81 can be inserted through the opening 213 in the bottom plate 211 into the recess 51 of the stator housing 5. Preferably, the stator housing 5 is attached to the outside of the bottom plate 211, for example by screws (not represented).
[0071] The assembly of the single-use device 100 and the reusable device 200 to form the mixing device 1 is extremely simple, as well as quick and, in particular, can be carried out without tools. For this purpose, the mixing container 110, which is usually folded up for storage, with the cup 81 sealingly attached thereto is placed in the support container 210, and the cup 81 with the impeller 10 arranged therein is inserted through the opening 213 in the bottom plate 211 into the recess 51 of the stator housing 5. Even then, the mixing device 1 is ready for use. After use, the mixing container 110 together with the cup 81 and the impeller 10 is simply pulled out of the support container 210. This particularly simple and trouble-free connection or separation of the single-use device 100 with or from the reusable device 200 thus takes account of a substantial aspect of the embodiment for single use.
[0072] Such embodiments are also possible in which the mixing container 110 is designed as a dimensionally stable mixing container 110, so that no support container 210 is required. If the mixing container 110 is designed as a dimensionally stable mixing container 110, it can be designed for single use and made, for example, of a plastic, or the mixing container 110 can be designed for multiple use, i.e., reusable, and made, for example, of a metallic material such as stainless steel.
[0073] If the mixing container 110 is designed as a dimensionally stable mixing container 110, it can also be designed in one piece with the cup 81 so that the cup 81 is an integral component of the mixing container. Of course, such embodiments are also possible in which the cup 81 is a separate component that can be sealingly connected to the dimensionally stable mixing container 110.
[0074] In the following, a preferred embodiment of the stator 4 of the mixing device 1 according to the disclosure is explained on the basis of
[0075] This electromagnetic rotary drive, which comprises the stator 4 and the magnetically effective core 3, is designed here as a temple motor.
[0076] In a temple motor, the stator 4 comprises a plurality of coil cores 45, here six coil cores 45, each of which comprises a rod-shaped longitudinal limb 46 extending from a first end 461 in the axial direction A to a second end 462, and a transverse limb 47 arranged at the second end 462 of the longitudinal limb 46. Each transverse limb 47 extends in a radial direction toward the magnetically effective core 3 and is delimited by an end face facing the magnetically effective core 3.
[0077] The first ends 461 of all longitudinal limbs 46 are magnetically conductively connected to each other via a reflux 42. The reflux 42 is preferably designed in a ring-shaped manner or comprises several segments that connect the longitudinal limbs 46 to one another. Both the reflux 42 and the coil cores 45 of the stator 4 are each made of a soft magnetic material because they serve as flux conducting elements to guide the magnetic flux. Suitable soft magnetic materials for the coil cores 45 and the reflux 42 are, for example, ferromagnetic or ferrimagnetic materials, i.e., in particular iron, nickel-iron, cobalt-iron, silicon iron or Mu-metal. In this case, a design as a stator sheet stack is preferred for the stator 4, in which the coil cores 45 and the reflux 42 are designed in sheet metal, i.e., they consist of several thin sheet metal elements, which are stacked.
[0078] Thus, each coil core 45 has a shape of an L, wherein the longitudinal limbs 46 each form the long limb of the L extending in the axial direction A, and the transverse limbs 47 extending perpendicular to the longitudinal limbs 26 in the radial direction toward the magnetically effective core 3 each form the short limb of the L. The plurality of the rod-shaped longitudinal limbs 46, which extend in the axial direction A and are reminiscent of the columns of a temple, have given the temple motor its name.
[0079] Each transverse limb 47 forms a stator pole 41 in each case. The stator poles 41 are arranged around the magnetically effective core 3, i.e., the magnetically effective core 3 of the impeller 10 is surrounded by the stator poles 41 in the operating state. The windings 6, which are preferably designed as concentrated windings 6, are arranged at the longitudinal limbs 46. One of the concentrated windings 6 is arranged at each longitudinal limb 46, which surrounds the respective longitudinal limb 46.
[0080] In this sense, the term temple motor is to be understood in the context of the present application.
[0081] The coil cores 45 are arranged equidistantly on a circular line so that the end faces of the transverse limbs 47 surround the magnetically effective core 3 of the impeller. The magnetically effective core 3 is designed as a permanent magnetic disk or as a permanent magnetic ring which is preferably diametrically magnetized. The magnetization of the magnetically effective core 3 is indicated in each case by the arrow without reference sign in
[0082] The stator 4 of the electromagnetic rotary drive is designed as a bearing and drive stator, with which the impeller 10 can be magnetically levitated without contact with respect to the stator 4 in the operating state.
[0083] In addition, the impeller-as already mentioned-can be magnetically driven without contact for rotation about the desired axis of rotation by the stator 4. The desired axis of rotation D refers to that axis about which the magnetically effective core 3 rotates in the operating state when the magnetically effective core 3 is in a centered and not tilted position with respect to the stator 4. This desired axis of rotation D defines the axial direction A. Usually, the desired axis of rotation D defining the axial direction A corresponds to the central axis of the stator 4.
[0084] Preferably, the electromagnetic rotary drive 1 is designed according to the principle of the bearingless motor and is operated according to this principle. The term bearingless motor means an electromagnetic rotary drive in which the magnetically effective core 3and thus the impeller 10is levitated completely magnetically with respect to the stator 4, wherein no separate magnetic bearings are provided. For this purpose, the stator 4 is designed as a bearing and drive stator, which is both the stator 4 of the electric drive and the stator of the magnetic levitation. A magnetic rotating field can be generated with the electrical windings 6 of the stator 4, which on the one hand exerts a torque on the impeller 10, which effects its rotation about the desired axis of rotation D, and which, on the other hand, exerts a shear force, which can be adjusted as desired, on the magnetically effective core 3 in a radial plane R (
[0085] Thus, three degrees of freedom of the impeller 10 can be actively regulated, namely its rotation and its radial position (two degrees of freedom). With respect to three further degrees of freedom, namely its position in the axial direction A and tilting with respect to the radial plane R perpendicular to the desired axis of rotation D (two degrees of freedom), the impeller 10 is passively magnetically levitated or stabilized by reluctance forces, i.e., it cannot be controlled. The absence of a separate magnetic bearing with a complete magnetic levitation of the magnetically effective core 3 is the property, which gives the bearingless motor its name. In the bearing and drive stator 4, the levitating function cannot be separated from the drive function.
[0086] In the case of a bearingless motor, in contrast to classical magnetic bearings, the magnetic levitation and the drive of the motor is realized by electromagnetic rotating fields. Typically, in the bearingless motor, the magnetic drive and levitation function is generated by the superposition of two magnetic rotating fields, which are usually designated as the drive and control fields. These two rotating fields generated by the windings 6 of the stator 4 usually have a pole pair number that differs by one. For example, if the drive field has the pole pair number p, the control field has the pole pair number p+1 or p?1. In this case, tangential forces acting on the magnetically effective core 3 in the radial plane are generated by the drive field, causing a torque, which causes the rotation about the axial direction A. Due to the superposition of the drive field and the control field, it is also possible to generate a shear force on the magnetically effective core 3 in the radial plane which can be adjusted as desired, with which the position of the magnetically effective core 3 in the radial plane can be regulated. Thus, it is not possible to divide the electromagnetic flux generated by the concentrated windings 6 into an (electro-) magnetic flux that only provides for driving the rotation and an (electro-) magnetic flux that only realizes the magnetic levitation.
[0087] To generate the drive field and the control field, it is possible on the one hand to use two different winding systems, namely one to generate the drive field and one to generate the control field. The coils for generating the drive field are then usually designated as drive coils and the coils for generating the control field as control coils. The current impressed in these coils is then designated as the drive current or the control current. On the other hand, it is also possible to generate the drive and levitation function with only one single winding system as in the embodiment described here, so that there is thus no distinction between drive coils and control coils. This can be realized in such a way that the values for the drive current and the control current determined in each case by a control device (not represented) are added or superimposed by calculationi.e., for example, with the aid of softwareand the resulting total current is impressed into the respective concentrated winding 6. In this case, of course, it is no longer possible to distinguish between control coils and drive coils.
[0088] In the embodiment of the stator 4 described here, exactly one concentrated winding 6 is thus arranged around each longitudinal limb 46. In the operating state, those electromagnetic rotating fields are generated with these concentrated windings 6 with which a torque is effected on the impeller 10 and with which a shear force, which can be adjusted as desired, can be exerted on the magnetically effective core 3 of the impeller 10 in the radial direction, so that the radial position of the magnetically effective core 3, i.e., its position in the radial plane R perpendicular to the axial direction A, can be actively controlled or regulated.
[0089] The control device, which comprises, for example, the power electronics for controlling and supplying the windings 6 as well as the signal processing electronics, is preferably arranged in the stator housing 5.
[0090] Further details on the structure and design of the bearingless motor can be found, for example, in EP 4 083 431.
[0091] The stator housing 5 preferably forms a jacket around the stator 4. The stator 4 is preferably encapsulated by the stator housing 5. Preferably, the encapsulation of the stator 4 is designed as a hermetic encapsulation. Preferably, the stator housing 5 is made of materials that are electrically non-conductive or at least only slightly conductive and yet durable. In addition, the stator housing 5 is made of materials that are solvent-resistant, so that the stator housing 5 can be cleaned with alcohol or other solvents. For example, plastics such as polyetheretherketone (PEEK) or polyoxymethylene copolymer (POM-C) belong to the non-conductive materials. Metal alloys such as Hastelloy or high-alloy titanium alloys (for example, Grade 5) belong to the relatively poorly conductive materials.
[0092] Furthermore, it is a preferred measure that the stator housing 5 with the components of the stator 4 arranged therein is preferably cast with a plastic, for example with an epoxy resin, polyurethane or silicone. This has the advantage that the stator 4 remains very dimensionally stable, even if the stator housing 5 is designed with a thin wall.
[0093]
[0094] The rotor housing 2 comprises the encapsulation 21 or is designed as an encapsulation, by which the magnetically effective core 3 is encapsulated. The encapsulation 21, which completely encloses the magnetically effective core 3, is preferably made of a plastic. For. example, it is possible to cast the magnetically effective core 3 in a plastic. It is also possible to design the rotor housing 2 in two parts, namely with a cup-shaped base part and a lid arranged thereon (not represented). The magnetically effective core 3 is then inserted into the base part and fixed there. Subsequently, the lid is placed on the base part and firmly connected to it, for example by welding or bonding. The fixing of the magnetically effective core 3 in the base part can be achieved by a press fit, for example, so that an interference fit is produced. However, it is also possible to cast the base part with a plastic after insertion of the magnetically effective core 3 in order to fix the magnetically effective core 3 with respect to the rotor housing 2.
[0095] In the embodiment represented in
[0096] As is known per se, the relief bore(s) 23 serves/serve to compensate at least partially for the axial thrust generated by the rotating vanes 7, thereby relieving the axial levitation of the impeller 10.
[0097] In the embodiment represented in
[0098] Each vane 7 extends in a generally radial direction from a radially inward beginning 75 to a radially outward end 76 which projects beyond the rotor housing 2 with respect to the radial direction. Each vane 7 is arranged with a radial distance D1 from the desired axis of rotation D, i.e., the radially inward beginning 75 of each vane 7 has the radial distance D1 different from zero from the desired axis of rotation D. Preferably, the radial distance D1 is identical for all vanes 7.
[0099] Each vane 7 has a front side 71, a back side 72, an upper edge 73 and a lower edge 74.
[0100] The front side 71 and the back side 72 are the faces of the vane 7 which are primarily responsible for mixing the substances. The front side 71 precedes the back side 72 when the impeller 10 rotates. The rotation of the impeller is indicated by the arrows with the reference sign U in
[0101] The upper edge 73 and the lower edge 74 delimit the vane 7 with respect to the axial direction A, wherein the upper edge 73 is arranged at that end of the vane 7, which faces away from the rotor housing 2, and wherein the lower edge 74 is that edge, which is arranged on or in the rotor housing 2.
[0102] Furthermore, a stabilizing element 9 is provided at each vane 7 for stabilizing the impeller 7 against tilting. The arrangement and design of the stabilizing elements 9 will be discussed in detail later.
[0103] Each stabilizing element 9 is arranged on the front side 71 or on the back side 72 of a vane 7. Of course, a stabilizing element 9 can also be arranged on each front side 71 and on each back side 72 in each case (see, for example,
[0104] Each stabilizing element 9 extends in each case with respect to the radial direction from a radial inner edge 91 to a radial outer edge 92 of the stabilizing element 9. Each stabilizing element 9 is designed and arranged in such a way that each radial outer edge 92 has a distance D92 from the desired axis of rotation D which is smaller than half the outer diameter DA of the impeller 10. This means that the stabilizing elements 9 are not arranged at the radially outward end 76 of the respective vane 7 but are spaced from it with respect to the radial direction. With respect to the radial direction, the stabilizing elements 9 thus end further inwards than the vanes 7.
[0105] Embodiments are possible in which each radial outer edge 92 has a distance D92 from the desired axis of rotation D which is at most 90% or at most 80% or at most 70% of half the outer diameter AD of the impeller 10.
[0106] Embodiments are also possible in which each radial outer edge 92 has a distance D92 from the desired axis of rotation D which is at most half, i.e. at most 50%, of half the outer diameter AD of the impeller 10, see e.g.
[0107] Furthermore, it is preferred that the radial inner edge 91 of each stabilizing element 9 has a distance D91 from the desired axis of rotation D which is greater than the radial distance D1 of the vanes 7 from the desired axis of rotation D. This means, with respect to the radial direction, the radial inner edges 91 of the stabilizing elements 9 lie further out than the radially inward beginning 75 of the vanes 7.
[0108]
[0109] The magnetically effective core 3 (not represented in
[0110] As can be recognized in
[0111] Alternatively, or complementarily, the lower end face 26 is designed with a chamfer 261 (not represented in
[0112] Particularly preferably, both the upper end face 25 and the lower end face 26 of the rotor housing 2 are each designed with a chamfer 251, 261. The tilting clearance which the impeller 10 has is increased by the chamfers 251, 261. The impeller 10 can be tilted further with the chamfers 251, 261, without the rotor housing 2 coming into physical contact with the cup 81.
[0113] The hub disk 78 is fixedly connected to the rotor housing 2. As this is represented in
[0114] Of course, it is also possible to attach the hub disk 78 to the upper face 25 by some other connection, for example by a bayonet connection or a snap-on connection, or with a non-detachable connection such as a weld or a gluing.
[0115] Several receptacles 781 are provided in the hub disk 78, into which the vanes 7 can be inserted. The receptacles 781 can be designed in such a way that they simultaneously cause a fixing of the respective vane 7 relative to the hub disk 78. Of course, it is also possible to fix the vanes 7 in the receptacles 781 by other methods, for example by gluing or welding.
[0116] Furthermore, embodiments are possible in which the vanes 7 are an integral part of the hub disk 78, i.e., they are designed in one piece with the hub disk 78.
[0117]
[0118] The single-use device 100 comprises the impeller 10, the cup 81 and the fixing means 120. The fixing means 120 is designed in such a way that it retains the magnetically effective core 3and thus the impeller 10in the cup 81 by means of magnetic forces.
[0119] For the preferred permanent magnetic embodiment of the magnetically effective core 3, the fixing means 120 comprises a soft magnetic disk 121 to which a strap 122 is attached.
[0120] The impeller 10 is inserted into the cup 81 so that the rotor housing 2 with the magnetically effective core 3 arranged therein rests on the bottom of the cup 81. Subsequently, the soft magnetic disk 121 is placed on the bottom of the cup 81 from the outside so that the bottom of the cup 81 is located between the rotor housing 2 and the soft magnetic disk 121. Due to the magnetic interaction between the soft magnetic disk 121 and the permanent magnetic designed magnetically effective core 3, the rotor housing 2and thus the impeller 10is fixed in the cup 81.
[0121] Before the cup 81 is inserted into the recess 51 of the stator housing 5, the fixing means 120 can be removed by pulling on the strap 122, thereby separating the soft magnetic disk 121 from the bottom of the cup 81.
[0122] The fixing means 120 is particularly advantageous for transporting the single-use device 100, because the impeller 10 is held in a well-defined position, namely in the cup 81 by the fixing means 120.
[0123] If the magnetically effective core 3 is designed as a reluctance rotor or without a permanent magnet, a permanent magnetic disk is used instead of the soft magnetic disk 121.
[0124] In the following, different variants for the embodiment of the impeller 10 with the stabilizing elements 9 are explained with reference to
[0125] Furthermore, it should be emphasized that specific measures which are explained by way of example on the basis of one of the variants can also be combined with measures and embodiments which are explained on the basis of other variants, i.e., the measures and embodiments explained in each case can also be combined with other variants.
[0126] It is also understood that each of the variants can also be designed with a hub disk.
[0127] With the exception of
[0128] In all variants described in the following, the impeller 10 is designed in each case with exactly five vanes 7, which are arranged equidistantly along the circumference of the impeller 10. Although the embodiment with exactly five vanes 7 is a preferred embodiment, the disclosure is of course not limited to a number of exactly five vanes. The impeller 10 can also be designed with fewer than five vanes 7, for example with exactly three or exactly four vanes 7, or with more than five vanes 7, for example with exactly six or exactly seven vanes 7.
[0129] According to the disclosure, the stabilizing elements 9 for stabilizing the impeller 10 against tilting are each arranged between two vanes 7. This feature comprises the two basic possibilities that the stabilizing elements 9 are arranged directly at the rotor housing 2 or, if present, at the hub disk 78, and with respect to the circumferential direction between two vanes 7, or that the stabilizing elements 9 are each arranged at the front side 71 or at the back side 72 of a vane 7. This stabilizing element 9 is arranged between two vanes 7 even in the case of the arrangement at the front side 71 or at the back side 72 of a vane 7, namely between the vane 7 at whose front side 71 or back side 72 the stabilizing element 9 is arranged and the adjacent vane 7 as seen in the circumferential direction. Combinations of these two possibilities can also be realized, namely embodiments of the impeller 10 in which stabilizing elements 9 are arranged both directly at the rotor housing 2 or at the hub disk 78 and at the front sides 71 or back sides 72 of the vanes 7.
[0130]
[0131] The stabilizing elements 9 are each arranged at the lower edge 74 of the vane 7 with respect to the axial direction A. The stabilizing elements 9 are arranged approximately centrally at the vane 7 with respect to the radial direction, so that the distance of the radial inner edge 91 of the stabilizing element 9 from the radially inward beginning 75 of the vane 7 is approximately the same as the distance of the radial outer edge 92 of the stabilizing element 9 from the radially outward end 76 of the vane 7.
[0132] Of course, it is also possible that the stabilizing elements 9 are each arranged at the front side 71 of a vane 7.
[0133] In the variant represented in
[0134]
[0135]
[0136]
[0137]
[0138] Of course, all positions with respect to the axial direction A and with respect to the radial direction are possible, in particular the positions represented in
[0139] The symmetrical arrangement is a particularly preferred measure.
[0140]
[0141] The radial inner edges 91 of the stabilizing elements 9 are designed in such a way that they are each drawn up to the upper end face 25 of the rotor housing 2, so that each stabilizing element 9 is physically connected not only to the respective vane 7 but also to the rotor housing 2. The resulting increase in the mechanical strength of the vane 7 allows larger and, in particular, longer vanes 7. As a result, the mixing device 1 can be operated with slower rotating vanes 7 while maintaining the same mixing efficiency, thus shifting the beginning of undesirable cavitations to higher torques.
[0142] As a further measure, the vanes 7 are designed in a curved manner as seen in the radial direction, so that the front side 71 of the vanes is designed in a convex manner in each case and the back side 72 is designed in a concave manner in each case.
[0143] As a further option, the upper edges 73 of the vanes 7 include a chamfer 731 in their radially outer area, so that the extension of the vane 7 in the axial direction A decreases in this radially outer area as the distance from the desired axis of rotation D increases. The chamfer 731 can be designed in a straight manner or in a curved manner.
[0144] Further possibilities for the embodiment are that the lower edge 74 of the vanes 7 is also designed with a chamfer in its radially outer area, or that the upper edge 73 and/or the lower edge 74 each include a straight-line or a curved chamfer in their radially inward area. Embodiments are also possible in which each vane 7 is designed in such a way that it tapers continuously with increasing distance from the desired axis of rotation D, i.e., it becomes narrower with respect to the extension in the axial direction A.
[0145]
[0146] In the embodiment shown in
[0147] In general, those embodiments are preferred in which the stabilizing elements 9 are arranged close to the magnetically effective core 3 with respect to the axial direction A and further inward with respect to the radial direction, i.e., closer to the desired axis of rotation D.
[0148] In
[0149] In the variant represented in
[0150] In the embodiment represented in
[0151]
[0152]
[0153] It is understood that in those embodiments in which the stabilizing elements 9 are arranged directly at the front side 71 and/or at the back side 72 of the vanes 7, a stabilizing element 9 need not be provided on each vane 7.
[0154]
[0155] Of course, there are many other possible embodiments, for example, the vanes 7in a straight designcan be arranged in such a way that they do not extend in the radial direction but are arranged inclined against the radial direction. Embodiments are also possible in which the vanes 7 are arranged inclined against the axial direction A in such a way that the lower edge 74 of the vane 7 is arranged offset with respect to the circumferential direction to the upper edge 73 of the same vane 7.
[0156] For the mixing device 1 according to the disclosure, which comprises the single-use device 100 and the reusable device 200, it is further an important aspect that the single-use device 100 must be sterilizable for some applications. In this regard, it is particularly advantageous if the single-use device 100 is gamma-sterilizable. In this type of sterilization, the element to be sterilized is applied with gamma radiation. The advantage of gamma sterilization, for example in comparison with steam sterilization, is in particular that sterilization can also take place through the package. For single-use devices in particular, it is a common practice that the parts are placed in the package after they are manufactured and then stored for a period of time before being shipped to the customer. Sterilization then usually takes place shortly before delivery to the customer or only by the customer. In such cases, sterilization takes place through the package, which is not possible with steam sterilization or other processes.
[0157] With regard to the single-use device 100, it is generally not necessary for it to be sterilizable more than once. This is a great advantage, particularly in the case of gamma sterilization, because the application of gamma radiation to plastics can lead to degradation, so that multiple gamma sterilization can render the plastic unusable.
[0158] Since sterilization under high temperatures and/or under high (steam) pressure can usually be dispensed with for single-use devices 100, less expensive plastics can be used, for example those that cannot withstand high temperatures or that cannot be subjected to multiple high temperature and pressure levels.
[0159] Considering all these aspects, it is therefore preferred to use such plastics that can be gamma-sterilized at least once for the manufacture of the single-use device 100. The materials should be gamma-stable for a dose of at least 40 kGy to enable a single gamma sterilization. In addition, no toxic substances should be generated during gamma sterilization. In addition, it is preferred that all materials that come into contact with the substances to be mixed or the intermixed substances meet USP Class VI standards.
[0160] For manufacturing the single-use device 100, the following plastics are suitable, for example: polyvinyl chloride (PVC), polypropylene (PP), polyethylene (PE), low density polyethylene (LDPE), ultra-low density polyethylene (ULDPE), high density polyethylene (HDPE), ethylene vinyl acetate (EVA), polyethylene terephthalate (PET), polyvinylidene fluoride (PVDF), acrylonitrile butadiene styrene (ABS), polyurethane (PU),polyacryl, polycarbonate (PC), polysulfones such as polysulfone (PSU), silicones.