Magnetic coupling pump assembly

Abstract

The present invention relates to a magnetic coupling pump assembly, wherein the magnetic coupling pump assembly comprises: an internal space (11) formed by a pump housing (2) of the pump assembly; a storage can (10) having a central longitudinal axis (B), wherein the chamber (12) enclosed by the storage can is hermetically sealed with respect to the internal space (11) formed by the pump housing (2); an impeller shaft (13) capable of being driven rotatable about a rotation axis (A); an impeller (16) mounted on one end of the impeller shaft (13); an inner rotor (17) mounted on the other end of the impeller shaft (13) and supporting a plurality of magnets (18); and an outer rotor (24) disposed on a driving shaft (20), interacting with the inner rotor (17) and supporting a plurality of magnets (23). According to the present invention, two magnets (23) adjacent in the axial direction of the outer rotor (24) are arranged to have a circumferential offset (V), and a virtual line (LV) extending through the same corner points of each of the two magnets (23) adjacent in the axial direction and a virtual line (L) extending parallel to the rotation axis (A) form an offset angle (α).

Description

Technology Field

[0001] The present invention relates to a magnetic drive pump assembly, wherein the magnetic drive pump assembly comprises: an internal space formed by a pump casing of the pump assembly; a storage can having a central longitudinal axis, wherein the chamber enclosed by the storage can is hermetically sealed to the internal space formed by the casing; an impeller shaft capable of being driven rotatably around a rotation axis; an impeller disposed at one end of the impeller shaft; an inner rotor disposed at the other end of the impeller shaft and also supporting a plurality of magnets; and an outer rotor disposed on a driving shaft, interacting with the inner rotor and supporting a plurality of magnets. Background Technology

[0002] Pumps without shaft seals like this are used to transport particularly dangerous or toxic media, as even small amounts of the transported medium can result in life-threatening consequences depending on the medium, and this is intended to prevent leakage.

[0003] In such pumps, a rotating magnetic field induces eddy currents in a metal housing can positioned between the inner rotor and the outer rotor. This statically positioned housing can, together with the casing cover and the pump casing itself, forms a pressure-bearing pump part, thereby allowing the inner rotor located inside the casing to be in continuous contact with the medium to be transported. To reduce eddy currents and, in this regard, prevent the medium from being continuously heated to its evaporation point, a metallic housing can material with high electrical resistance is generally used. In particular, expensive nickel-based alloys have been widely used for this purpose. The problem to be solved

[0004] The object of the present invention is to reduce eddy-current loss in a storage can within a magnetic region of a pump assembly, particularly a magnetic drive pump assembly. means of solving the problem

[0005] The above objective of the present invention is achieved by a configuration in which two magnets adjacent in the axial direction of the outer rotor are arranged to have a circumferential offset, and an imaginary line extending through the same corner points of the two magnets adjacent in the axial direction and an imaginary line extending parallel to the axis of rotation form an offset angle. According to the staggered configuration of the magnets, the effect of vortices flowing in an inclined direction through the storage can is produced. Due to the extension of the associated vortex path, resistance increases. Therefore, the vortices within the storage can are reduced, and thereby the vortex loss is also reduced.

[0006] It is advantageous for the axially adjacent magnets of the inner rotor to be arranged to have a circumferential offset. The offset arrangement of the magnets of the inner rotor compensates for the reduction in maximum transmissible torque caused by the load angle changing in the axial direction.

[0007] In another embodiment, one or both of the outer rotor and the inner rotor may be manufactured modularly into a plurality of axially continuous annular partial outer rotors or partial inner rotors. Here, the individual magnets are attached to the associated partial rotors, and the offset angle between axially adjacent magnets arises from the offset of the axially adjacent partial rotors.

[0008] For easy assembly of the above-mentioned partial rotors, each of the partial outer rotors and the partial inner rotors has a first end face and a second end face located opposite the first end face, and a plurality of through-holes extend from the first end face to the second end face through the individual partial rotors in a manner substantially parallel to the axis of rotation, and a rod extends through each of the through-holes, and the individual partial rotors are engaged with each other by the rods by means of appropriate means.

[0009] It is preferable that the above offset and the resulting offset angle be configured to have orientations that alternately face clockwise and counterclockwise along the axial direction, that is, to have a zigzag-like configuration. As a result, the length of the vortex path is extended, and the additional axial force generated due to the inclined configuration is compensated.

[0010] It has been found to be particularly advantageous to have a plurality of elevations on the outer lateral surface of the storage can, wherein the outer lateral surface has a substantial undulating form having a plurality of undulation peaks and a plurality of undulation troughs, and the elevations are arranged at an angle with respect to a virtual line extending parallel to the axis of rotation on the outer lateral surface, and an angle is formed by the virtual line corresponding to the elevations or the course of the elevations and the line extending through the same corner points of two magnets adjacent in the axial direction with respect to the virtual line corresponding to the course of the elevations, and the line forms an angle substantially between 45° and 135°, particularly substantially 90°.

[0011] It has been found that it is particularly advantageous for the above-mentioned inclined rising sections to have a direction reversal at or near the center of the cylindrical part of the storage can, and according to this configuration, a substantially mirror-inverted course of the rising sections is realized, and the magnets of the outer rotor are offset in the opposite direction. As a result, the advantage is obtained that the length of the vortex path is extended and the additional axial force generated due to the inclined configuration is compensated. Brief explanation of the drawing

[0012] Exemplary embodiments of the present invention will be described in detail below with reference to the attached drawings. FIG. 1 shows a cross-sectional view of a magnetic drive pump assembly according to the prior art. Figure 2 shows a three-dimensional view of a device including an inner rotor, a storage can, and an outer rotor. FIG. 3 shows a schematic diagram of a device according to the present invention having magnets of an inner rotor and an outer rotor. Figure 4 shows a schematic diagram of the vortex path in a storage can when the magnets are arranged in the conventional manner. FIG. 5 shows a schematic diagram of a vortex path in a storage can in the case of an exemplary device according to the present invention equipped with magnets. FIG. 6 shows a cross-sectional view of a device according to the present invention having an inner rotor, a storage can, and an outer rotor. Figure 7 shows a three-dimensional view of an additional device including an inner rotor, a storage can, and an outer rotor. Figure 8 shows a detailed view of the device illustrated in Figure 7. Figure 9 shows an additional detailed view of the device illustrated in Figure 7. FIG. 10 shows a detailed view of an alternative device including an inner rotor, a storage can, and an outer rotor. Figure 11 shows a detailed view of an additional alternative device including an inner rotor, a storage can, and an outer rotor. FIG. 12 illustrates a schematic diagram of a device according to the present invention having magnets of an outer rotor, wherein the storage can is shown having rising portions on the outer side surface. FIG. 13 shows a diagram of an apparatus according to the present invention having magnets of the outer rotor positioned relative to the rising portions of FIG. 12. FIGS. 14a and 14b show a simplified illustration of a device according to the present invention equipped with magnets of an outer rotor, in which additional variations of a storage can are shown. Specific details for implementing the invention

[0013] FIG. 1 illustrates a pump assembly (1) in the form of a magnetic drive pump assembly known as the prior art as an example. The pump assembly (1) comprises a multi-part pump casing (2) of a centrifugal pump, said pump casing comprising a hydraulic casing (3) in the form of a spiral casing, a casing cover (4), a bearing carrier intermediate bracket (5), a bearing carrier (6), and a bearing cover (7).

[0014] The fluid casing (3) has an inlet opening (8) for sucking in the medium to be transported and an outlet opening (9) for discharging the transported medium. A casing cover (4) is positioned on the side of the fluid casing (3) opposite the inlet opening (8). A bearing carrier intermediate bracket (5) is fastened on the side of the casing cover (4) facing away from the fluid casing (3). A bearing carrier (6) is attached to the side of the bearing carrier intermediate bracket (5) facing away from the casing cover (4). The bearing cover (7) is again fastened on the side of the bearing carrier (6) facing away from the bearing carrier intermediate bracket (5).

[0015] A storage can (10) is attached to the side of the casing cover (4) facing away from the fluid casing (3), and the storage can extends at least partially through an internal space (11), which is defined by a pump casing (2) (particularly the casing cover (4)), a bearing carrier intermediate bracket (5), and a bearing carrier (6). The storage can (10) hermetically seals the chamber (12) enclosed by the storage can with respect to the internal space (11).

[0016] An impeller shaft (13) rotatable around a rotation axis (A) extends from a flow chamber (14) enclosed by a fluid casing (3) and a casing cover (4) to a chamber (12) through an opening (15) provided in the casing cover (4).

[0017] The impeller (16) is connected to the shaft end of the impeller shaft (13) located within the flow chamber (14), and the inner rotor (17) is positioned at the opposite shaft end and is also positioned within the chamber (12). The inner rotor (17) is provided with a plurality of magnets (18) positioned on the inner rotor (17) side facing the storage can (10).

[0018] A bearing assembly (19) is disposed between the impeller (16) and the inner rotor (17), and the bearing assembly is operably connected to an impeller shaft (13) that can be driven to rotate about a rotation axis (A).

[0019] Preferably, a drive motor (not shown), which is an electric motor, drives the drive shaft (20). The drive shaft (20), which can be driven rotatably about a rotation axis (A), is positioned substantially coaxially with respect to the impeller shaft (13). The drive shaft (20) extends through a bearing cover (7) and a bearing carrier (6), and is also mounted within two ball bearings (21, 22) housed in the bearing carrier (6). An outer rotor (24) supporting a plurality of magnets (23) is positioned at the free end of the drive shaft (20). The magnets (23) are positioned on the side of the outer rotor (24) facing the storage can (10). The outer rotor (24) extends at least partially beyond the storage can (10) and interacts with the inner rotor (17), and by its magnetic force, the rotating outer rotor (24) causes rotational movement of the inner rotor (17), and furthermore the impeller shaft (13) and the impeller (16).

[0020] The structure of the inner rotor (17), single-wall storage can (10), and outer rotor (24) of the present invention, as illustrated in the enlarged view of FIG. 2, is provided to be installed in a pump assembly (1) as an example of various magnetic drive pump assemblies. The inner rotor (17) has a plurality of magnets (18) positioned on the side facing the storage can (10), particularly in the cylindrical wall region of the storage can (10). The outer rotor (24) has a plurality of magnets (23) similarly connected to face the storage can (10).

[0021] FIG. 3 illustrates a simplified illustration of the magnets (18) of the inner rotor (17) and the magnets (23) of the outer rotor (24) in a structure possible according to the present invention. For the sake of understanding, parts of the inner rotor and the outer rotor supporting the magnets (18, 23) are omitted from the illustration. For reference, a storage can (10) is illustrated between the magnets (18, 23). It can be seen that two magnets (23) adjacent in the axial direction of the outer rotor (24) are arranged to have a circumferential offset (V). A virtual line (L) extending through the same corner points (25, 25') of the two magnets (23) adjacent in the axial direction V A virtual line (L) extending parallel to the rotation axis (A) and the rotation axis (A) forms an offset angle (α). The offset angle (α) shown in an exemplary embodiment is 14.5°. Here, the offset angle (α) is formed clockwise with respect to the line (L).

[0022] The radial shift is denoted by V. In the illustrated exemplary embodiment, two magnets (18) adjacent to the inner rotor (17) in the axial direction are also offset by the same offset angle (α). The magnets (23) of the outer rotor (24) and the magnets (18) of the inner rotor (17) are arranged to form an areal overlap with each other, at least theoretically, or to be able to perform an areal overlap with each other, where different diameters of the outer rotor (24) and the inner rotor (17) are taken into account. However, a configuration in which only magnets adjacent to one rotor (inner rotor (17) or outer rotor (24)) in the axial direction are offset is also possible.

[0023] FIG. 4 schematically illustrates a vortex path (26) within a storage can (10) in which the magnets (18) of the inner rotor (17) or the magnets (23) of the outer rotor (24) are arranged in a known manner.

[0024] FIG. 5 schematically illustrates a vortex path (26') in the case where the magnets (18) of the inner rotor (17) or the magnets (23) of the outer rotor (24) are offset according to the present invention. Here, it can be seen that the vortex path (26') within the storage can (10) has a longer vortex path length than the vortex path (26) shown in FIG. 4. Thus, the vortex induced in the storage can (10), more specifically in the wall of the storage can, has an oblique profile.

[0025] FIG. 6 shows a cross-sectional view of the structure of the inner rotor (17), storage can (10), and outer rotor (24) shown in FIG. 2, where the radial offset (V) of the outer rotor is shown.

[0026] In the embodiment of FIG. 7, the inner rotor (17) is modularly composed of a plurality of annular partial inner rotors (17a, 17b, 17c, 17d) that are axially continuous. For better understanding, refer to FIG. 8, where only the magnets (23) of the outer rotor (24) are substantially illustrated, the outer rotor (24) is formed by a plurality of annular partial outer rotors (24a, 24b, 24c, 24d) that are axially continuous. The partial inner rotors (17a–17d) and the partial outer rotors (24a–24d) may be offset in rotational direction relative to each other in any necessary manner to set the offset (V) of the individual magnets (18, 23) (see FIG. 3 and 6). It can be seen that, if necessary, it is possible to manufacture only one of the inner rotor (17) and the outer rotor (24) using partial rotors (17a~17b or 24a~24b).

[0027] According to one example illustrated in FIG. 9, an outer rotor (24) is manufactured by assembling the partial outer rotors (24a–24d) of FIG. 7 and FIG. 8, and only the partial outer rotors (24c, 24d) are illustrated in FIG. 9. Each of the partial outer rotors (24a–24d) has a first end face (27) and a second end face (28) located on the opposite side of the first end face (27). A plurality of through holes (29) substantially parallel to the axis of rotation (A) extend through the partial outer rotors (24a–24d) from the first end face (27) to the second end face (28).

[0028] Additionally, rods (30) extend through through holes (29), and each rod (30) extends through all of the partial outer rotors (24a–24d). The partial outer rotors (24a–24d) can be engaged and secured to each other using appropriate means (not shown). The rods (30) may be in the form of, for example, threaded rods or may have threads on at least their free ends, and the partial outer rotors (24a–24d) can be engaged and secured to each other by screwing in threaded nuts. Also, the rods (30) may be in the form of rivets. It is obvious that the inner rotor (17) can also be configured in the same way.

[0029] In addition to the through holes (29) shown, additional through holes (29) spaced apart from each other may be provided, and accordingly, the desired offset (V) can be obtained by rotating the corresponding partial rotors (17a~17d or 24a~24d) around the axis of rotation (A) and then fitting them into the rods (30).

[0030] Apart from the rotational offset of adjacent partial rotors around the rotation axis (A), an additional rotational offset of 180° around the vertical axis (X) is also possible, which again increases the number of possible offset angles (α).

[0031] FIGS. 10 and 11 illustrate another embodiment of the present invention, wherein the axial offset (V) and the corresponding offset angle (α) alternately have clockwise and counterclockwise orientations to extend the vortex path length and compensate for additional axial forces generated due to the inclined configuration.

[0032] In the embodiment of FIG. 10, the offset size of the partial outer rotor (24a) with respect to the partial outer rotor (24b) is different from the offset size of the partial outer rotor (24b) with respect to the partial outer rotor (24c). In this example, the offset size of the partial outer rotor (24c) with respect to the partial outer rotor (24d) is larger than the offset size of the partial outer rotor (24a) with respect to the partial outer rotor (24b) and the offset size of the partial outer rotor (24b) with respect to the partial outer rotor (24c).

[0033] In the embodiment of FIG. 11, the size of the offset (V) of the partial outer rotor (24a) with respect to the partial outer rotor (24b) is the same as the size of the offset of the partial outer rotor (24b) with respect to the partial outer rotor (24c) and the size of the offset of the partial outer rotor (24c) with respect to the partial outer rotor (24d). Thus, the value of the offset angle (α) between the two magnets (23) of the axially adjacent outer rotors (24) is uniform.

[0034] FIG. 12 illustrates a simplified illustration of a possible arrangement of magnets (23) of an outer rotor (24) according to the present invention. For the sake of understanding, parts of the outer rotor supporting the magnets (23) are omitted from the illustration. In the illustrated embodiment, the storage can (10) has an outer lateral surface (31) having a plurality of rising portions (32). The outer lateral surface (31) has a substantially corrugated shape by having a plurality of corrugated upper portions (33) and a plurality of corrugated lower portions (34). Channel-shaped cavities (not illustrated) may extend through the rising portions (32).

[0035] In the region of the magnets (23), the rising portions (32) have a shape similar to a spiral or screw, that is, the rising portions (32) are positioned at an angle with respect to a virtual line (L) that extends parallel to the axis of rotation (A) of the outer lateral surface (31). In the illustrated embodiment, the virtual line (L) corresponding to the rising portions (32) or the course of the rising portions (32) E ) and the line (L) form an angle (β) of 45°. Here, the angle (β) is formed counterclockwise with respect to the line (L). The angle (β) may be in the range greater than 0° and less than 90°. Preferably, the angle (β) is located within the range between 30° and 70°. A virtual line (L) extending through the corner points of two axially adjacent magnets (23) V ) and the line (L) form an offset angle (α) of 14.5°.

[0036] Here, the offset angle (α) is formed clockwise with respect to the line (L).

[0037] As shown in FIG. 13, the line (L E ) and line(L V It has been proven to be particularly advantageous when ) forms a 90° angle (φ).

[0038] FIG. 14a and FIG. 14b, respectively, illustrate schematic diagrams of additionally possible configurations of the magnets (23) of the outer rotor (24) according to the present invention. The inclinedly extending risers (32) are reversed in direction at or near the center of the cylindrical portion of the storage can (10), so that the risers (32) are formed as a substantially mirror-inverted course. Accordingly, the magnets (23) are offset in opposite directions.

[0039] The present invention has been described based on an example in which the number of axially adjacent magnets (17 or 23) is three or four, but the actual number of axially adjacent magnets (17 or 23) may be greater than this.

Claims

Claim 1 As a magnetic drive pump assembly, the magnetic drive pump assembly comprises: - an internal space (11) formed by a pump casing (2) of the pump assembly; - a containment can (10) having a central longitudinal axis (B), which hermetically seals a chamber (12) enclosed by the containment can with respect to the internal space (11) formed by the casing (2); - an impeller shaft (13) capable of being driven rotatably about a rotation axis (A); - an impeller (16) disposed at one end of the impeller shaft (13); - an inner rotor (17) disposed at the other end of the impeller shaft (13) and supporting a plurality of magnets (18); and- comprising an outer rotor (24) disposed on a drive shaft (20), interacting with the inner rotor (17), and supporting a plurality of magnets (23); wherein two magnets (23) adjacent in the axial direction of the outer rotor (24) are arranged to have a circumferential offset (V), and an imaginary line (L) extending through the same corner points of the two magnets (23) adjacent in the axial direction V A magnetic drive pump assembly characterized in that a virtual line (L) extending parallel to the rotation axis (A) and the rotation axis (A) forms an offset angle (α). Claim 2 In claim 1, two magnets (18) adjacent in the axial direction of the inner rotor (17) are arranged to have a circumferential offset (V), and a virtual line (L) extending through the same corner points of two magnets (23) adjacent in the axial direction V A magnetic drive pump assembly characterized in that a virtual line (L) extending parallel to the rotation axis (A) and the rotation axis (A) forms an offset angle (α). Claim 3 A magnetic drive pump assembly according to claim 1 or 2, characterized in that the outer rotor (24) is manufactured in a modular fashion by means of a plurality of annular partial outer rotors (24a, 24b, 24c, 24d) that are continuous in the axial direction. Claim 4 A magnetic drive pump assembly according to any one of claims 1 to 3, wherein the inner rotor (17) is manufactured in a modular manner by means of a plurality of axially continuous ring-shaped inner rotors (17a, 17b, 17c, 17d). Claim 5 A magnetic drive pump assembly according to claim 3 or 4, wherein each partial outer rotor (24a, 24b, 24c, 24d) and partial inner rotor (17a, 17b, 17c, 17d) has a first end face (27) and a second end face (28) located opposite to the first end face (27), and a plurality of through-holes (29) extend from the first end face (27) to the second end face (28) through the individual partial rotors (17a, 17b, 17c, 17d, 24a, 24b, 24c, 24d) in a manner substantially parallel to the axis of rotation (A). Claim 6 A magnetic drive pump assembly according to claim 5, characterized in that a rod (30) extends through each of the through holes (29), and individual partial rotors (17a, 17b, 17c, 17d, 24a, 24b, 24c, 24d) are braced to each other by the rods (30). Claim 7 A magnetic drive pump assembly, characterized in that, in any one of claims 3 to 6, the offset (V) and the offset angle (α) have orientations that alternately face clockwise and counterclockwise along the axial direction. Claim 8 In any one of the preceding claims, the storage can (10) has an outer lateral surface (31) having a plurality of elevations (32), the outer lateral surface (31) has a substantial undulating form having a plurality of undulation peaks (33) and a plurality of undulation troughs (34), the elevations (32) are arranged at an angle with respect to a virtual line (L) extending parallel to the axis of rotation (A) on the outer lateral surface (31), and the virtual line (L) corresponding to the elevations (32) or the course of the elevations (32). E An angle (β) is formed by the line (L) and the above line, and a virtual line (L) corresponding to the course of the rising parts (32) E A line (L) extending through the same corner points of two axially adjacent magnets (23). V A magnetic drive pump assembly characterized by forming an angle (φ) substantially between 45° and 135°, particularly substantially 90°. Claim 9 A magnetic drive pump assembly according to claim 8, wherein the inclinedly extended rising portions (32) are reversed in direction at or near the center of the cylindrical part of the storage can (10) to form a substantially mirror-inverted course of the rising portions (32), and the magnets (23) are offset in opposite directions.

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