Pump assembly

Abstract

The invention relates to a pump assembly (1), in particular a magnetically coupled pump assembly, having an interior space (11) formed by a pump housing (2) of the pump assembly (1); a spacer tank (10) which hermetically seals a chamber surrounded by the spacer tank from an interior space (11) formed by the pump housing (2); an impeller shaft (20) rotatably drivable about an axis of rotation (A); an impeller (23) disposed at one end of the impeller shaft (20); an inner rotor (24) arranged at the other end of the impeller shaft (20); and an outer rotor (38) interacting with the inner rotor (24). A coupling flange (27) for fastening the spacer tank (10) to the pump housing (2) or to a component associated with the pump housing (2) is formed at the open end of the spacer tank (10).

Description

Technical Field

[0001] This invention relates to a pump assembly, particularly a magnetic coupling pump assembly (or magnetic coupling pump assembly, i.e., Magnetkupplungspumpenanordnung), the pump assembly having an internal space formed by a pump housing of the pump assembly; a spacer tank (or isolation sleeve, i.e., Spalttopf) that provides an airtight seal for a chamber surrounded by the spacer tank relative to the internal space formed by the pump housing; an impeller shaft rotatably driven about 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 an outer rotor that interacts with the inner rotor. Background Technology

[0002] A magnetically coupled pump (also known as a magnetically driven pump or magnetic coupling pump) is a type of centrifugal pump in which the driving power required by the pump is transmitted magnetically. Unlike traditional pumps, where there is a direct mechanical connection between the motor and the pump, a magnetically coupled pump uses magnetic coupling to transmit motion from the motor to the pump.

[0003] The magnetic coupling consists of two magnetic rotor assemblies isolated from each other by a housing. One rotor assembly is connected to a motor, while the other is connected to a pump. Both rotor assemblies are equipped with magnets that attract each other and thus transmit rotational motion. Through the magnetic field, the two rotor assemblies can rotate together without any mechanical connection.

[0004] The advantage of magnetic coupling pumps lies in the completely static seal provided for the medium being pumped. Because there is no direct mechanical connection between the pump shaft and the motor shaft, liquid or gas cannot reach the environment through potential leaks at dynamic seals. This makes magnetic coupling pumps ideally suited for demanding applications requiring high reliability and chemical resistance.

[0005] Such pump assemblies are known from DE 10 2004 003 400 A1, which, in order to broaden their application range, have a drive rotor constructed to be identical to that used for external drive elements. However, this only expands the application range to a certain extent. From a given set of structural parameters, matching the rotor parameters is unavoidable.

[0006] A modular structural kit for manufacturing pumps is known from EP 0 814 268 A1. This kit should provide the possibility of arbitrarily producing pumps from a small number of structural components according to application requirements. However, the proposed solution only allows for the replacement of components belonging to a single structural parameter.

[0007] DE 10 2014 214 929 A1 describes a magnetically coupled pump in which two stationary sliding ring seals are used. Therefore, the stationary spring element does not vibrate, thereby improving the service life and sealing effect of the sliding ring seals.

[0008] DE 10 2013 208 460 A1 illustrates the positioning of an axial support assembly in a magnetically coupled pump, wherein the lubrication of the support assembly is improved and the acting radial support force is reduced.

[0009] DE 10 2013 007 849 A1 discloses an auxiliary impeller arranged at the inner rotor of a magnetically coupled pump. This auxiliary impeller generates a forced circulation of lubricant flow during operation, which in particular lubricates the support components, and also removes heat generated by eddy current losses from the spacer tank area.

[0010] In known magnetic coupling pumps to date, the spacer tank is typically welded to a flange to secure it to the pump housing. This welded connection usually has a different microstructure than the spacer tank and / or flange, and thus may constitute a weakness in the sense of a predetermined fracture point during the operation of the magnetic coupling pump. Welded connections are costly, labor-intensive, and difficult to control. Summary of the Invention

[0011] The objective of this invention is to provide a pump assembly, particularly a magnetically coupled pump assembly, that does not have the aforementioned weak point at the spacer tank. The spacer tank should provide a durable, hermetically sealed seal for the pump assembly. Furthermore, the spacer tank should be characterized by a compact structural form. The structure of the spacer tank should facilitate the replacement of spare parts. The spacer tank should be simple and cost-effective to implement.

[0012] This task is solved according to the invention by a pump assembly, particularly a magnetically coupled pump assembly, as described in claim 1. Preferred variations can be obtained from the parallel independent claims, dependent claims, description, and drawings.

[0013] According to the invention, a connecting flange is provided at the open end of the spacer tank for fixing the spacer tank to the pump housing or to a component belonging to the pump housing, such as a housing cover.

[0014] For example, the connecting flange is constructed as an extended or thickened portion of the spacer tank, extending beyond the columnar dimensions of the spacer tank.

[0015] Additionally, the connecting flange preferably functions as a connector that links the spacer tank to the pump housing or components associated with the housing, particularly the housing cover. The connecting flange provides increased strength and stability and ensures a secure connection of the spacer tank to the housing or housing cover.

[0016] For example, the connecting flange also serves as a support element, providing additional stability and / or reinforcement to the spacer tank and thereby reducing the load on the seals. The special structure of the connecting flange protects the spacer tank from deformation and / or breakage.

[0017] In addition, the connecting flange preferably also performs specific functions, such as accommodating fixing elements for installing and / or removing spacers at the housing.

[0018] Ideally, the connecting flange and the spacer tank are constructed as a single unit.

[0019] Advantageously, the connecting flange and the spacer are manufactured in a modular fashion, and thus constructed together continuously through modular manufacturing processes. This eliminates the need for the otherwise common and separate welded connections. In this case, the flange and the spacer are designed and manufactured as a single unit from the outset. This means that the connecting flange and the spacer are already interconnected in their final shape and position.

[0020] In generative manufacturing processes, such as selective laser melting, the connecting flange and spacer are constructed in layers. Here, the connecting flange and spacer are printed as a single structure. The connecting flange and spacer are thus interconnected during the "printing process," forming a single, integrated structure.

[0021] In contrast to welding, bonding, or other joining techniques, the implementation of a one-piece structure involves the connecting flange and the spacer being designed and manufactured as a continuous component and a single unit from the outset. In this one-piece structure, the connecting flange and the spacer are not separate or isolated, but rather form a continuous, undivided structure. This provides the possibility, in a particular embodiment of the spacer, integrating the connection channel between the spacer, particularly the spacer's base, and the connecting flange. The outer circumferential surface of the base has multiple protrusions, within which hollow spaces are provided, extending into the connecting flange. The internal pressure of the hollow spaces can be monitored to prevent potential damage to the spacer and, consequently, spillage of the transported medium.

[0022] For example, the connecting flange and the spacer tank form a monolithic structure. The term "monolithic" means that the flange and the spacer tank are composed of a single piece, rather than being assembled as separate components. The term "monolithic" emphasizes the unity and integrity of the integrated structure, which is designed and manufactured as a continuous unit.

[0023] Preferably, the connecting flange is constructed as a ring element. The ring element relates to a structure having a closed loop shape.

[0024] Ideally, the connecting flange is fixed to the housing or to a component belonging to the housing, such as the housing cover of the pump housing. Thus, the spacer is secured in its position between the inner and outer rotors, and is arranged safely and permanently.

[0025] For example, the connecting flange has at least four, preferably at least eight, and especially at least twelve columnar sleeves. These sleeves serve as mounting holes in the embodiments to accommodate fastening elements, such as threaded parts, whose planar supports achieve a defined fixation at the housing or housing cover.

[0026] In an advantageous variant of the invention, the connecting flange has a protrusion that interacts with a sealing element and a groove in the housing or housing cover. The protrusion extends axially from the connecting flange toward the housing or a component associated with the housing, such as a housing cover. Preferably, the sealing element is implemented as a graphite sealing ring, which is press-fitted into a groove in the housing cover by the protrusion of the connecting flange. Alternatively, the seal may comprise, for example, PTFE, EPDM, etc. Thus, the spacer—especially in the area fixed to the housing or a component associated with the housing—can be implemented in a hermetically sealed manner, even under challenging pressure and / or temperature conditions.

[0027] Ideally, the connecting flange is not produced as a solid material, but rather has an advantageous structure consisting of multiple supporting elements. These elements are implemented, for example, as ribs and / or tabs.

[0028] Ribs and / or tabs are structural elements used to enhance the stiffness and strength of the connecting flange. Reinforcing ribs or tabs increase the bending stiffness of the connecting flange. This reduces the flexibility and bending of the connecting flange, resulting in improved structural integrity and enhanced load-bearing capacity. Furthermore, a self-supporting geometry is achieved, enabling unsupported manufacturing via selective laser melting, thus saving significant material in the manufacture of spacer tanks.

[0029] Alternatively or as a supplement, the connecting flange has a plate-like reinforcing structure.

[0030] Plate-like reinforcing structures are flat, plate-like elements that are integrated in a generative manner along the structure of the connecting flange to improve its stiffness, strength, and stability. Plate-like reinforcing structures can have different shapes and parameters related to the load specifications of the pump assembly, and they can be designed, for example, in rectangular, square, circular, or other geometries.

[0031] For example, the flange has multiple recesses in the form of bevels (or flanks, i.e., Fasen), which are preferably arranged as bevels next to and around ribs, tabs, and plate-like reinforcing structures. Here, the recesses, together with the ribs, tabs, and plate-like reinforcing structures, form a static and structural structure optimized for minimum mass and maximum bending stiffness.

[0032] In an advantageous variation, the connecting flange has at least one annular surface for a support structure required during manufacturing using an additive method. The support structure is created during the manufacturing process and then removed again, leaving only the support structure surface. In the advantageous variation, this surface is as small as possible to minimize the amount of support or auxiliary material required when using selective laser melting. This annular support structure surface, for example, forms the outer edge of the connecting flange.

[0033] Ideally, the annular support structure is constructed as a hollow column extending to the height of the flange. The support structure extends substantially coaxially with the base of the spacer tank and is built together with the spacer tank structure from the base plate or build platform of the 3D printer.

[0034] Additionally, the connecting flange may also have two and / or three and / or four radially spaced annular support structures. Here, the annular support structures may be interrupted by sleeves of the fixing elements, wherein the sleeves are advantageously supported in their arrangement and strength by the annular support structures. Therefore, ribs, tabs, and plate-like reinforcing structures originate from and / or converge at the annular support structures.

[0035] In an advantageous variation of the invention, the connecting flange and the spacer are constructed of a metallic material having properties comparable to those of conventional cast materials.

[0036] According to the present invention, the pump assembly, particularly the integral structure of the connecting flange and the spacer, is manufactured by means of a method in which the spacer with the connecting flange is produced by selectively melting a powder layer through energy radiation.

[0037] Selective laser melting (SLM) is an additive manufacturing method used to manufacture connecting flanges and spacer tanks from metal powder in an embodiment as a monolithic structure. Here, in the finished state, the material preferably possesses the properties of a castable material. A form of 3D printing is also involved, in which a high-power laser is used to selectively melt powder and build the spacer tank and connecting flange layer by layer.

[0038] The spacer tank with connecting flanges is constructed layer by layer by applying a thin layer of powder to a construction platform. A laser beam is then directed at a selected area, where it melts the metal powder and bonds it into a strong layer. New layers are then applied and the process is repeated until a spacer tank with connecting flanges is created.

[0039] Preferably, a high-power laser, such as a fiber laser or a CO2 laser, is used. The laser beam is precisely controlled to melt and fuse the metal powder. Laser parameters such as power, intensity, and speed are set according to process requirements and the selected material. For example, laser parameters can also be locally matched to achieve a defined and desired microstructure.

[0040] After laser melting, spacer tanks with connecting flanges may require post-processing, such as to achieve a flat surface for the protrusions and / or sleeves, or to remove the support structure.

[0041] Ideally, the combination of recesses with ribs, tabs, and plate-like reinforcing structures is conceived to have sufficient metal mass to dissipate heat during the selective laser melting process, but at the same time, the implementation of the recesses will not result in too much metal mass, which will lead to a large amount of heat dissipation.

[0042] Here, the height of the flange is set to ensure that the connecting flange is constructed with sufficient rigidity to prevent deformation and to achieve a seal by means of a sealing element.

[0043] The spacer tank has a base with multiple protrusions on its outer circumference, in which hollow spaces are provided, extending to the connecting flange.

[0044] According to the present invention, the pump assembly, together with the spacer tank and the connecting flange in an integrated structure, is used for the airtight and sealed delivery of fluids. Attached Figure Description

[0045] Other features and advantages of the invention are derived from the description of the embodiments with the aid of the accompanying drawings and from the drawings themselves.

[0046] This is shown here: Figure 1 The longitudinal section of the magnetically coupled pump assembly is shown. Figure 2 A perspective view of a spacer tank with a constructed flange is shown. Figure 3 A detailed cross-section through the flange is shown. Figure 4 A detailed cross-section is shown through the flange with two annular support structures. Figure 5 A top view of a flange with two annular support structures is shown. Detailed Implementation

[0047] Figure 1 An exemplary pump assembly 1 is shown in the form of a magnetically coupled pump assembly 1 as known in the prior art. The pump assembly 1 has a multi-piece pump housing 2 of a centrifugal pump, which includes a hydraulic housing 3 configured as a helical shell, a housing cover 4, a support cover 5, a support 6, and a support cover 7.

[0048] The hydraulic housing 3 has an inlet opening 8 for drawing in the conveying medium and an outlet opening 9 for discharging the conveying medium. The housing cover 4 is located on the side of the hydraulic housing 3 opposite to the inlet opening 8. The support cover 5 is fixed to the side of the housing cover 4 away from the hydraulic housing 3. The support 6 is located on the side of the support cover 5 opposite to the housing cover 4. The support cover 7 is also fixed to the side of the support 6 away from the support cover 5.

[0049] The spacer 10 is fixed to the side of the housing cover 4 opposite to the hydraulic housing 3 and extends at least partially through the internal space 11 defined by the pump housing 2, and in particular by the housing cover 4, the support cover 5, and the support 6. The spacer 10 provides an airtight seal for the chamber 12 it surrounds relative to the internal space 11.

[0050] An impeller shaft 13, which can rotate about the rotation axis A, extends from a flow chamber 14, which is limited by a hydraulic housing 3 and a housing cover 4, through an opening 15 provided in the housing cover 4, into the chamber 12.

[0051] An impeller 16 is fixed at the shaft end of the impeller shaft 13 located within the flow chamber 14, and an inner rotor 17 is arranged at the opposite shaft end within the chamber 12. The inner rotor 17 is equipped with a plurality of magnets 18, which are arranged on the side of the inner rotor 17 facing the spacer tank 10.

[0052] A support assembly 19 is arranged between the impeller 16 and the inner rotor 17 and is operatively connected to the impeller shaft 13, which is rotatably driven around the rotation axis A.

[0053] A drive shaft 20, preferably an electric motor (not shown), is driven by a drive motor. The drive shaft 20, rotatable about a rotation axis A, is substantially coaxial with the impeller shaft 13. The drive shaft 20 extends through the support cover 7 and the support seat 6 and is supported at two ball bearings 21, 22 mounted in the support seat 6. An outer rotor 24 carrying a plurality of magnets 23 is arranged at the free end of the drive shaft 20. The magnets 23 are arranged on the side of the outer rotor 24 facing the spacer tank 10. The outer rotor 24 extends at least partially over the spacer tank 10 and interacts with the inner rotor 17, such that the rotating outer rotor 24, by means of magnetic force, also puts the inner rotor 17 into rotational motion, and thus puts the impeller shaft 13 and the impeller 16 into rotational motion.

[0054] Figure 2 The spacer tank 10 shown in the mid-perspective is configured for mounting to various magnetically coupled pump assemblies, exemplarily in... Figure 1 In the pump assembly 1 shown, the spacer tank 10 has a substantially columnar base 25, the base having a shape consistent with that of the pump assembly 1 shown in the figure. Figure 1 The rotation axis A is substantially coaxial with the central longitudinal axis B. The base 25 is open on one side and closed on the opposite side by means of a substantially arched bottom 26. An annular connecting flange 27 is arranged on the open side, which is integrally constructed with the base 25.

[0055] The connecting flange 27 has multiple openings 28 extending parallel to the central longitudinal axis B, in Figure 1 The threaded part 34 shown can be inserted through the opening and screwed into according to Figure 1 In the corresponding threaded hole in the housing cover 4.

[0056] The bottom 26 is composed of a generally spherical cap region 29 and an eave region 30 located on the outside forming the transition region between the substrate 25 and the cap region 29.

[0057] The base 25 has an outer peripheral surface 31 with multiple protrusions 32. The outer peripheral surface 31 is substantially wavy, with corresponding multiple peaks 33 and troughs 34. The protrusions 32 are threaded or spindle-shaped. A hollow space (not shown) is provided in the protrusions 32. The hollow space can be used by a sensor monitoring and control module to detect damage to the spacer tank 10 before fracture occurs during pump operation and to switch the pump assembly 1 to a safe state.

[0058] In the illustrated implementation variant, the connecting flange 27 has twelve columnar sleeves 33 that define an opening 28. Figure 1 The threaded part 34 shown extends through the sleeve 33 or the opening 28 for securing the spacer 10 to the housing cover 4.

[0059] A plate-shaped reinforcing structure 35 is arranged at the transition between the spacer tank 10, particularly the base 25, and the connecting flange 27. The plate-shaped reinforcing structure 35 strengthens the embodiment of the connecting flange 27 and also serves as a support structure when constructing the spacer tank 10 with the connecting flange 27 during the selective laser melting process. Furthermore, the plate-shaped reinforcing structure 35 dissipates heat to the base 25 and the support structure required during manufacturing when melting metal powder to construct the connecting flange 27.

[0060] The spacer tank 10 has an annular first flange 36 in the area of ​​the connecting flange 27, which has a plurality of ribs 37 and tabs 38.

[0061] The stability and bending stiffness of the connecting flange 27 are achieved through the combination of the first flange with the rib 37 and the tab 38. Recesses 39 are created therebetween, reducing the amount of material required and minimizing the support structure surface 40 needed for selective laser melting. The columnar sleeve 33 is secured by the first flange 36.

[0062] The support structure, not shown in the figure, is created during the manufacturing process. After the spacer tank 10 is completed using a selective laser melting process, the support structure is removed again, leaving only the support structure surface 40.

[0063] The connecting flange 27 and the spacer tank 10 form a continuous, undivided structure, which provides the possibility of integrating a connecting channel 41 between the spacer tank 10, and in particular the base 25 of the spacer tank 10 and the connecting flange 27.

[0064] Figure 3 A detailed cross-section through the connecting flange 27 is shown. The connecting flange 27 includes an axial protrusion 42, which works in conjunction with a sealing element and a groove (not shown) in the housing cover 4 to also achieve an airtight seal design of the spacer tank 10 at the connection point.

[0065] The effective height X of the connecting flange 27 is a parameter that defines the stiffness of the connecting flange 27. The effective height X reduces the height of the recess 39. This reduces the mass of the connecting flange 27, and also reduces the amount of metal powder required and the cost-intensive build time in SLM (Selective Laser Melting).

[0066] The ribs 37, the connecting pieces 38, and the plate-like reinforcing structure 35 form, in the cross-sectional view, visible, interlocking first and second inclined surfaces 43 and 44, with the first and second inclined surfaces defining recesses 39. This reduces the support depth Z, which is typically required in fixed flanges in other cases, to a support depth Y, corresponding to the width of the annular support structure surface 40.

[0067] Figure 4 Basically corresponds to Figure 3 A detailed cross-section through another embodiment of the connecting flange 27 is shown. For the higher pressure within the spacer tank 10, it is necessary to construct the connecting flange 27 thicker in the axial direction. To save material for the required support structure during manufacturing using selective laser melting, the connecting flange 27, in addition to the first annular flange 36, has a second annular flange 45 arranged radially spaced from the first flange 36. The second flange 45 has a support structure surface 46.

[0068] exist Figure 5 The diagram shows a top view of the connecting flange 27, which has a first flange 36 and a second flange 45. At the transition between the spacer tank 10, particularly the base 25, and the connecting flange 27, a plate-like reinforcing structure 35 is constructed in an embodiment with a 45° bevel.

[0069] The stability and bending stiffness of the connecting flange 27 are achieved not only through the plate-shaped reinforcing structure 35, but also through the combination of the first flange 36, the rib 37, and the connecting piece 38. A recess 39 is arranged between them. The columnar sleeve 33 is fixed by the first flange 36 and the second flange 45.

Claims

1. A pump assembly (1), particularly a magnetically coupled pump assembly, the pump assembly having an internal space (11) formed by a pump housing (2) of the pump assembly (1); a spacer tank (10) that hermetically seals a chamber surrounded by the spacer tank relative to the internal space (11) formed by the pump housing (2); an impeller shaft (20) rotatably driven about a rotation axis (A); an impeller (23) disposed at one end of the impeller shaft (20); an inner rotor (24) disposed at the other end of the impeller shaft (20); and an outer rotor (38) acting in conjunction with the inner rotor (24). Its features are, A connecting flange (27) is provided at the open end of the spacer tank (10) for fixing the spacer tank (10) to the pump housing (2) or to a component belonging to the pump housing (2).

2. The pump assembly according to claim 1, characterized in that, The connecting flange (27) and the spacer tank (10) are constructed as a single unit.

3. The pump assembly according to claim 1 or 2, characterized in that, The connecting flange (27) is constructed as a ring element.

4. The pump assembly according to any one of claims 1 to 3, characterized in that, The connecting flange (27) has a protrusion (41) that interacts with the sealing element and with the groove of the housing cover (4).

5. The pump assembly according to any one of claims 1 to 4, characterized in that, The connecting flange (27) has multiple ribs (37) and / or tabs (38).

6. The pump assembly according to any one of claims 1 to 5, characterized in that, The connecting flange (27) has a plate-shaped reinforcing structure (35).

7. The pump assembly according to any one of claims 1 to 6, characterized in that, The connecting flange (27) has multiple recesses (39).

8. The pump assembly according to any one of claims 1 to 7, characterized in that, The connecting flange (27) has at least one annular support structure surface (40).

9. The pump assembly according to any one of claims 1 to 8, characterized in that, The connecting flange (27) has at least four, preferably at least eight, and especially at least twelve columnar sleeves (16).

10. The pump assembly according to any one of claims 1 to 9, characterized in that, The connecting flange (27) and the spacer tank (10) are constructed of metal.

11. The pump assembly according to any one of claims 1 to 10, characterized in that, The spacer tank (10) has a base (25) with a plurality of protrusions (32) on its outer peripheral surface (31), wherein a hollow space is provided in the protrusions (32) and the hollow space extends into the connecting flange.

12. A method for manufacturing a pump assembly (1), characterized in that, The integral structure of the connecting flange (27) and the spacer (10) is generated by selectively melting the powder layer through energy radiation.

13. A pump assembly (1) having an integral structure of the spacer tank (10) and the connecting flange (27) for use in the airtight conveying of fluids.

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