WO2022038137A1

WO2022038137A1 - Pump assembly

Info

Publication number: WO2022038137A1
Application number: PCT/EP2021/072836
Authority: WO
Inventors: Tomasz MALOGOWSKI; Omar FRANCESCHI; Stefan TILLER; Hong Giang TO; Maurice ANDREE
Original assignee: Gkn Sinter Metals Engineering Gmbh
Priority date: 2020-08-20
Filing date: 2021-08-17
Publication date: 2022-02-24
Also published as: US20230304494A1; EP3957822A1; CN115943248A; EP3957822B1; SI3957822T1

Abstract

Disclosed is a pump assembly (1) at least comprising a pump (2) having a discharge side (3) and a suction side (4), and a drive unit (5) for the pump (2), the pump (2) and the drive unit (5) being arranged in a common housing (6), the drive unit (5) being an axial-flow electric drive comprising a stator (7), which is rotationally fixedly connected to the housing (6), and a rotor (8), which is rotatably arranged relative to the housing (6), a first end face (9) of the rotor (8) being oriented towards the stator (7) along an axial direction (10), the rotor (8) forming an outer pumping means (11) of the pump (2) and having a first pumping profile (13) on an inner circumferential surface (12); in a radial direction (14), an inner pumping means (15) of the pump (2) is arranged inside the rotor (8), said inner pumping means (15) having a second pumping profile (17) on an outer circumferential surface (16), said second pumping profile (17) interacting with the first pumping profile (13) to pump a fluid (18).

Description

hull arrangement

The invention relates to a pump arrangement, at least comprising a pump and a drive unit for the pump, which are arranged in a common housing. The drive unit is an axial flow electric drive, which comprises a stator which is non-rotatably connected to the housing and a rotor which is arranged such that it can rotate with respect to the housing. The rotor forms an outer conveying means of the pump and has a first conveying profile (e.g. a first set of teeth or vanes of a vane pump) on an inner peripheral surface, with an inner conveying means of the pump being arranged in a radial direction inside the rotor and on a Outer peripheral surface has a second conveying profile (e.g. a second toothing or a cylindrical outer peripheral surface), which interacts with the first conveying profile for conveying a fluid and optionally (in the case of the teeth) for driving the inner conveying means through the rotor.

In known pump designs, a rotor of the pump is arranged on an axle that is led out of a housing of the pump arrangement.

A pump assembly is z. B. known from DE 10 2015 207 748 A1. There, a fluid pump is described, which is driven by an electric motor. A pump rotor of the fluid pump is coupled to the electric motor. The electric motor is an axial flow electric motor whose electric motor rotor is also the pump rotor or drives a pump rotor. The pump rotor and the electric motor rotor are accommodated in a common housing in which the pump rotor and the electric motor rotor rotate integrated in a disk shape as a combination rotor, the common housing having a fluid inlet and a fluid outlet to the combination rotor. A pump chamber or fluid conveying chamber is closed off in the common housing and a fluid inflow and a fluid outflow to the pump chamber takes place axially along the axis of rotation.

A pump arrangement is known from DE 10 2017 113 825 A1, which comprises at least one pump and a drive unit for the pump, which are arranged in a common housing. The drive unit is an axial flow electric drive, which comprises a stator which is non-rotatably connected to the housing and a rotor which is arranged such that it can rotate with respect to the housing. The rotor forms an outer conveying means of the pump, with an inner conveying means of the pump being arranged in a radial direction inside the rotor, which is connected to the first conveying profile for conveying a fluid and, if necessary (in the case of the teeth) for driving the inner conveying means by the rotor interacts. The inner conveyor is arranged on a sleeve. A mechanical bearing of the outer conveyor and the rotor is not provided. In order to set an operation that is as leak-free as possible, the side walls surrounding the rotor are set at a certain distance from one another by means of a traction mechanism.

There is a constant need to further simplify such pumps and to make them robust and durable for operation. In particular, a compact pump arrangement is to be proposed which can be manufactured as simply as possible and can be operated largely without wear.

A pump arrangement with the features according to patent claim 1 contributes to the solution of these tasks. Advantageous developments are the subject matter of the dependent patent claims. The features listed individually in the patent claims can be combined with one another in a technologically meaningful manner and can be supplemented by explanatory facts from the description and/or details from the figures, with further embodiment variants of the invention being shown. A pump arrangement is proposed, at least comprising a pump with a pressure side and a suction side and a drive unit for the pump, which are arranged in a common housing. The drive unit is an axial flow electric drive, which (precisely) comprises a stator non-rotatably connected to the housing and (precisely) a rotor arranged rotatably relative to the housing. The rotor is arranged with a first end side opposite the stator or a stator-side housing (ie a housing enclosing the stator) along an axial direction and forms an external conveying means of the pump. The outer conveying means has a first conveying profile on an inner peripheral surface. An inner conveying means of the pump is arranged in a radial direction inside the rotor and has a second conveying profile on an outer peripheral surface, which interacts with the first conveying profile for conveying a fluid. The inner conveying means is mounted on a centering element which is non-rotatably connected to the housing. At least the rotor and the outer conveying means are set up to be mounted exclusively on the fluid conveyed by the pump (rotatable in relation to other components of the pump arrangement). A first fluid guide structure is arranged at least between the first end face (of the rotor/outer conveying means) and the stator (or the stator-side housing) and is connected to the pressure side, so that a gap between the first end face and the stator ( or the stator-side housing) can be produced by the fluid.

Electrical drives regularly include a stator and a rotor, which are arranged coaxially to one another. The rotor is referred to herein as the carrier of permanent magnets, while the stator comprises a coil assembly. In an axial flux motor, the rotor and stator are arranged one behind the other, in particular along the axial direction. Differently magnetized magnets are alternately arranged on the rotor along the circumferential direction.

The coil assembly of a stator has cores, e.g. B. from SMC, which are surrounded by current-carrying windings. Each kernel can be an element that arranged to become magnetized when a current is passed through live windings around the core. The current-carrying windings can be designed as coils.

In particular, SMC is formed from iron powder particles which are electrically insulated from one another. Iron losses in SMC parts in an alternating electric field are generally small. In this regard, it therefore seems desirable to use SMC in electrical machines, at least in part, instead of the most commonly used steel lamination (steel sheets or electrical steel). To form a component from SMC, the particles are compacted and hardened. The SMC material is not sintered here. Rather, tempering takes place below a melting temperature, which is however sufficient for the material to permanently retain the intended geometry.

The rotor of the electric drive can have permanent magnets or else soft-magnetic elements, for example in recesses. A permanently excited synchronous or brushless DC motor, abbreviated BLDC, can be formed with permanent magnets as an electric drive, while a reluctance motor can be created as an electric motor in an axial, radial or transverse design with soft magnetic elements, for example.

Rotor and stator together form in particular the drive unit of the pump arrangement.

The rotor has a first conveying profile (e.g. the first toothing) on the inner peripheral surface, via which the inner conveying means is connected to the second conveying profile (e.g. a second toothing) arranged on the outer peripheral surface of the inner conveying means for conveying the fluid works together. When the conveying profiles are designed as teeth, the inner conveying means is driven by the outer conveying means. A separate drive of the inner funding, z. B. on an axis of the inner funding is not required. In particular, the rotor and inner conveying means together form the pump of the pump arrangement, which conveys a fluid from a suction side or low-pressure side (fluid inlet) to a pressure side or high-pressure side (fluid outlet).

For such a pump arrangement z. B. Gerotor pumps and internal gear pumps (also referred to as sickle pumps) are suitable. Both pump types are characterized by rotors that are parallel but spaced apart from one another in the radial direction and have axes of rotation of the toothing (inner conveying means and outer conveying means). Due to the meshing teeth, one conveyor is driven by the drive of the other conveyor.

Vane cell pumps and roller cell pumps can also be used as the pump arrangement, with the outer conveying means comprising the vanes or rollers, which can be displaced in a radial direction relative to the axis of rotation, as the first conveying profile. The second funding profile is z. B. formed by a cylindrical outer peripheral surface of the inner conveyor, which cooperates with the wings or the rollers.

The rotor and the conveying means are arranged in particular with plain bearings. During operation of the pump arrangement, a fluid film builds up in the sliding bearing, in particular in the bearing acting opposite to the axial direction, which reduces the friction between components that move differently.

The rotor, in particular together with the outer conveying means, is in particular designed without a shaft or is arranged without bearings or only with sliding bearings in relation to the radial direction.

During operation of the axial flux electric drive, forces occur in the axial direction, which cause the rotor to be attracted along the axial direction towards the stator. works. In the embodiment proposed here for a compact pump arrangement with only one stator, these forces can result in the rotating rotor making contact with the stator or the housing surrounding the stator. This problem is exacerbated in pump arrangements in which the rotor is not arranged on a shaft or is not supported in relation to the radial direction, since the shaftless rotor can tilt more easily during operation. If the rotor is even slightly skewed (the end faces of the rotor generally cannot be produced perpendicular to the axis of rotation), only local contact between the rotor and the housing or stator can occur. The rotor can have a material-removing effect on the housing or the stator, which causes permanent damage to the pump arrangement and can significantly reduce its service life.

In the present pump arrangement, tilting of the rotor is prevented or reduced, among other things, in particular by the largest possible diameters of the surfaces of the rotor acting as bearings in relation to the axial direction.

It is proposed here that a first fluid guide structure is arranged between the first end face of the rotor and the stator or the stator-side housing and is connected to the pressure side, so that during operation of the pump arrangement there is a gap between the first end face and the stator or the stator-side Housing can be produced by the fluid. The pressure of the fluid set by the pump arrangement on the pressure side is used here to set and maintain the distance along the axial direction between the first end face and the stator or the housing.

The distance between the electromagnetic rotor part (the magnets) and the electromagnetic stator part is, in particular, approximately 0.5 mm and, in particular, is not appreciably influenced by the fluid. The distance that arises during operation of the pump arrangement between the rotor and stator or on the stator side Housing adjusts as a result of the fluid and forms the gap is in particular intended exclusively to prevent friction between the components and thus wear. The gap, ie the distance formed by the fluid, is in particular significantly smaller than the distance between the electromagnetic components of the rotor and stator.

The first fluid guide structure comprises in particular a channel structure which is formed at least on one of the surfaces forming the gap. These surfaces are formed at least by the first end face of the rotor and by the wall of the stator or housing lying opposite the first end face. In particular, therefore, there is no gap with a constant gap size, rather the gap size varies locally as a result of the channel structure implemented on at least one surface. The fluid can be conveyed through the gap (and across the gap) in particular at least along the radial direction via the channel structure. In particular, at least one flow channel is provided for the fluid, along which the fluid is conveyed through the gap (and across the gap).

In particular, the fluid should essentially be conveyed into the gap in order to reduce the friction between components there. In particular, conveying the fluid beyond the gap is only a technically necessary evil in order to convey the fluid into the gap. In particular, the fluid should not be conveyed in a targeted manner beyond the gap, but this internal leakage should be kept as small as possible.

In particular, a substantially constant pressure of the fluid is provided in the gap along the extension of the first fluid guide structure or along the channel structure. In particular, there are no throttling sections along the first fluid guide structure or along a flow channel of the channel structure that cause a gradual or continuous pressure drop. Included a throttled pressure can definitely exist between different flow channels of a channel structure.

In particular, the pump arrangement is designed in such a way that the pressure of the fluid on the pressure side generated during operation of the pump arrangement compensates for the axial forces acting between the stator and the rotor (straightforward). If necessary, the pressure of the fluid in the gap between the rotor and the stator can be adjusted via a (controllable or constant) throttle.

In particular, the rotor extends between a first end face facing the stator and a second end face arranged opposite along the axial direction over a width, with the first conveying profile and the second conveying profile each extending over the (same) width. In particular, the conveying profiles have the same width, so that the end faces of the inner conveying means and the outer conveying means can be arranged in alignment with one another along the radial direction.

In particular, the second conveying profile interacts with the first conveying profile to drive the inner conveying means, with the inner conveying means being rotatably mounted on the centering element. The inner conveying means is also stored exclusively via the fluid required by the pump.

In particular, the first fluid guide structure is also formed on the inner conveying means, so that a gap between the inner conveying means and the centering element can also be ensured here by the fluid during operation of the pump arrangement. In particular, the first fluid guide structure is designed differently here than between the rotor and stator, since the axial forces act essentially between the rotor and stator and are only transmitted via contact friction of the conveying profiles starting from the rotor or from the outer conveying means to the inner conveying means. In particular, on a second end face of the rotor arranged opposite the first end face, the housing has a pressure line connected to the pressure side of the pump arrangement. In particular, the first fluid guide structure is (exclusively) connected to the pressure line via the centering element and/or via the conveying profiles.

In particular, the fluid is conveyed from the pressure line (exclusively) via the centering element to the first fluid conducting structure.

In particular, the inner conveyor is rotatably mounted on a first outer peripheral surface of the centering element, with a second fluid conducting structure for connecting the pressure line to the first fluid conducting structure being formed at least partially on the first outer peripheral surface. In particular, hydrodynamic or hydrostatic mounting of the inner conveying means on the centering element can be implemented in this way.

The second fluid conducting structure can in particular be designed in the manner of the first fluid conducting structure, the second fluid conducting structure being provided for generating a gap running parallel to the axis of rotation between the centering element and the inner conveying means.

In particular, on a second end face of the rotor arranged opposite the first end face, the housing has a suction line connected to the suction side. A transfer of the fluid from the first fluid guide structure, which can be described as leakage, takes place in particular via a second outer peripheral surface of the rotor to the suction line. This leakage serves in particular to lubricate the opposing surfaces of the rotor and housing.

With the pump arrangement, a fluid can be conveyed through the conveying profiles, starting from the suction line to the pressure line. The amount used to lubricate and support the components and to ensure the gap of the fluid can flow (back) at least partially (as leakage) from the pressure side via the gap to the suction side.

In particular, the fluid is conveyed, starting from the pressure line, via the centering element and via the second fluid-guiding structure to the first end face of the rotor. In particular, the fluid (then, but in particular only as a leak) is conveyed outwards along the gap between the first end face and the stator and at least along the radial direction across the gap. The fluid (then) flows via the second outer peripheral surface of the rotor (ie between the housing and the rotor) towards the second end face and to the suction side arranged there.

In particular, the rotor and the outer conveying means are designed in one piece, preferably in one piece, ie manufactured together.

In particular, at least during operation of the pump arrangement, rotating components (rotor, outer conveying means, inner conveying means, the pump arrangement relative to stationary components (housing, stator, centering element) of the pump arrangement are arranged without contact. In particular, at least during operation of the pump arrangement, there is no mechanical contact between rotating components of the pump arrangement and fixed components of the pump assembly.

In particular, all rotating components run in the fluid. In particular, the fluid prevents contact between rotating components of the pump arrangement and stationary components of the pump arrangement, or ensures a non-contact arrangement.

In particular, tolerances of the components that would otherwise have to be produced with high precision can be softened, so that costs for the production of the pump arrangement can be reduced. The perpendicularity otherwise required between the axis of rotation and the first end face is here in particular with less accuracy perform, since the gap between the rotor and housing or stator is guaranteed by the fluid.

In particular, in this pump arrangement, the parallelism of the end faces of the rotor are the remaining important tolerances that have to be implemented very precisely. These can be produced much more cheaply (e.g. by double disc grinding).

In particular, at least the rotor is manufactured using powder metallurgy. In particular, at least the stator is manufactured by powder metallurgy. In particular, the rotor is also manufactured by sintering.

The pump is preferred

- A gerotor pump or an internal gear pump (also referred to as a sickle pump) and the first conveying profile is a first toothing and the second conveying profile is a second toothing, the toothings having different numbers of teeth from one another; or

- a vane pump or roller pump; wherein a first axis of rotation of the rotor and a second axis of rotation of the inner conveyor are arranged parallel to each other and spaced apart from each other in the radial direction.

In particular, the pump arrangement has exclusively static seals, that is to say seals which are only arranged between components which are arranged in a rotationally fixed manner. In this way, a secure and permanent seal can be guaranteed using exclusively static seals.

In particular, the pump arrangement has the following operating parameters:

- Rated power consumption in watts: from 0 to 2,000; preferably from 50 to 200;

- Nominal maximum working pressure in bar: from 0 to 100; preferably from 4 to 12;

- Flow rate in liters per minute: from 0 to 50; preferably from 3 to 12;

- Rotor speed in revolutions per minute: from 0 to 7,000; preferably from 1,000 to 4,000.

The gap between the first end face of the rotor (in particular not in the area of the magnets) and the housing or the stator, i.e. in particular the gap forming the sliding bearing or the gap formed by the first fluid conducting structure, is in particular at least 0.003 millimeters during operation of the pump arrangement , preferably at most 0.1 millimeters, particularly preferably at most 0.05 millimeters or even at most 0.01 millimeters.

In particular, the gap between the magnets and the housing or the stator is at least 0.2 millimeters, preferably at least 0.3 millimeters. The gap in this area is preferably at most 1.5 mm, particularly preferably at most 1.0 mm, in particular 0.3 to 0.7 mm.

The use of indefinite articles (“a”, “an”, “an” and “an”), particularly in the claims and the description reflecting them, is to be understood as such and not as a numeral. Correspondingly introduced terms or components are to be understood in such a way that they are present at least once and, in particular, can also be present several times.

As a precaution, it should be noted that the numerals used here (“first”, “second”, ...) primarily (only) serve to distinguish between several similar objects, sizes or processes, i.e. in particular no dependency and/or sequence of these objects, sizes or make processes mandatory for each other. Should a dependency and/or order be required, this is explicitly stated here or it is obvious to the Specialist in studying the specific configuration described. If a component can occur several times (“at least one”), the description of one of these components can apply equally to all or part of the majority of these components, but this is not mandatory.

The invention and the technical environment are explained in more detail below with reference to the accompanying figures. It should be pointed out that the invention should not be limited by the exemplary embodiments given. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in the figures and to combine them with other components and findings from the present description. In particular, it should be pointed out that the figures and in particular the proportions shown are only schematic. Show it:

Fig. 1: a pump assembly in an exploded view, in a perspective view;

Fig. 2: a pump assembly in a side view in section with a

Representation of the flow of the fluid from a pressure side to a suction side;

Fig. 3: the pump assembly in a side view in section with the

Flow path from the pressure side to the first end face;

FIG. 4: a part of the pump arrangement in a perspective view with part of the flow pattern according to FIG. 3;

FIG. 5: a part of the pump arrangement in a perspective view with a further part of the flow pattern according to FIG. 3, which follows the flow pattern according to FIG. 4; FIG. 6: a part of the pump arrangement according to FIG. 3 in a perspective view;

FIG. 7: a part of the pump arrangement in a perspective view with the part of the flow pattern according to FIG. 3 and a further part of the flow pattern which follows the flow pattern according to FIG. 5; and

FIG. 8: the pump arrangement according to FIG. 2 in a perspective view in section.

1 shows a pump assembly 1 in an exploded view, in a perspective view. Fig. 2 shows a pump arrangement 1 in a side view in section with an illustration of the flow path 34 of the fluid 18 from a pressure side 3 to a suction side 4. Fig. 3 shows the pump arrangement 1 in a side view in section with the flow path 34 from the pressure side 3 to the first end face 9. Fig. 4 shows a part of the pump assembly 1 in a perspective view with a part of the flow pattern 34 according to Fig. 3. Fig. 5 shows a part of the pump assembly 1 in a perspective view with a further part of the flow pattern 34 after 3, which follows the course of flow 34 according to FIG. FIG. 6 shows part of the pump arrangement 1 according to FIG. 3 in a perspective view. FIG. 7 shows a part of the pump arrangement 1 in a perspective view with the part of the flow path 34 according to FIG. 3 and a further part of the flow path 34 which follows the flow path 34 according to FIG. FIG. 8 shows the pump arrangement 1 according to FIG. 2 in a perspective view in section. 1 to 8 are described together below.

1 and 3 to 8 are not shown according to the invention only in relation to the rotor 8, the outer conveyor 11 and the inner conveyor 15. There, the rotor 8 is shown as an assembly consisting of two components. The funding Profiles 13, 17 of the conveying means 11, 15 do not extend as far as the first end face 9 but over a smaller width 23 than the rotor 8.

The pump arrangement 1 comprises a pump 2 with a pressure side 3 and a suction side 4 and a drive unit 5 for the pump 2, which are arranged in a common housing 6. The drive unit 5 is an axial flow electric drive, which includes precisely one stator 7 connected in a torque-proof manner to the housing 6 and precisely one rotor 8 arranged to be rotatable with respect to the housing 6 . The rotor 8 is arranged with a first end face 9 opposite the stator 7 along an axial direction 10 and forms an outer conveying means 11 of the pump 2 . The outer conveying means 11 has a first conveying profile 13 on an inner peripheral surface 12 . An inner conveying means 15 of the pump 2 is arranged in a radial direction 14 inside the rotor 8 and has a second conveying profile 17 on an outer peripheral surface 16 which interacts with the first conveying profile 13 for conveying a fluid 18 . The inner conveying means 15 is mounted on a centering element 19 which is non-rotatably connected to the housing 6 . The rotor 8 and the outer conveying means 11 are rotatably mounted relative to other components of the pump arrangement 1 exclusively via the fluid 18 conveyed by the pump 2 . A first fluid guide structure 20 is arranged between the first end face 9 and the stator 7 and is connected to the pressure side 3 so that a gap 21 can be created between the first end face 9 and the stator 7 through the fluid 18 during operation of the electric drive.

The coil assembly of the stator 7 has cores 32, e.g. B. from SMC, which are comprised of current-carrying windings 31.

The rotor 8 of the electric drive has magnets 33 . Cores 32 and windings 31 are spaced apart from magnets 33 by gap 21 . The rotor 8 has a first conveying profile 13 (here a first toothing) on the inner peripheral surface 12, via which the inner conveying means 15 and the second conveying profile 17 (here a second toothing) arranged on the outer peripheral surface 16 of the inner conveying means 15 for conveying the Fluid 18 interacts. When the conveying profiles 13, 17 are formed as toothings, the inner conveying means 15 is driven via the outer conveying means 11. A first axis of rotation 29 of the rotor 8 (and of the outer conveying means 11) and a second axis of rotation 30 of the inner conveying means 15 are arranged parallel to one another and spaced apart from one another in the radial direction 14 . Pump 2 is designed as a gerotor pump.

During operation of the axial flux electric drive, forces occur in the axial direction 10 which cause the rotor 8 to be attracted along the axial direction 10 towards the stator 7 . A gap 21 is set between the first end face 9 and the stator 7 by the fluid 18 during operation of the electric drive by the first fluid guide structure 20 which is arranged between the first end face 9 and the stator 7 and is connected to the pressure side 3 . The pressure of the fluid 18 set by the pump arrangement 1 on the pressure side 3 is used here to set and maintain the distance along the axial direction 10 between the first end face 9 and the stator 7 or the housing 6 .

The rotor 8 extends between a first end face 9 facing the stator 7 and an oppositely arranged second end face 22 along the axial direction 10 over a width 23, with the first conveying profile 13 and the second conveying profile 17 each extending over the same width 23, which according to FIG. 2 extend over the width 23 of the rotor 8 according to the invention and according to FIG. 1 and FIGS. 3 to 8 (not according to the invention) only over part of the width 23 of the rotor 8.

The housing 6 has a second end face 22 of the rotor 8 arranged opposite the first end face 9 and connected to the pressure side 3 Pressure line 24 (see Fig. 4), the first fluid guide structure 20 via the centering element 19 and/or via the conveying profiles 13, 17 (see Fig. 2, to the left of the axes of rotation 29, 30: connection between the pressure line 24 and the first fluid guide structure 20 also is connected to the pressure line 24 exclusively via conveyor profiles 13, 17).

The fluid 18 is starting from the pressure line 24 via the centering

19 and/or the conveying profiles 13, 17 are conveyed towards the first fluid guide structure 20 along a flow path 34 (see FIGS. 2 to 8).

The inner conveying means 15 is rotatably mounted on a first outer peripheral surface 25 of the centering element 19 , a second fluid conducting structure 26 for connecting the pressure line 24 to the first fluid conducting structure 20 being formed on the first outer peripheral surface 25 .

The housing 6 has, on a second end face 22 of the rotor 8 arranged opposite the first end face 9, a suction line 27 connected to the suction side 4, leakage of the fluid from the first fluid conduction structure

20 takes place via a second outer peripheral surface 28 of the rotor 8 towards the suction line 27 .

The fluid 18 is conveyed from the pressure line 24 via the centering element 19 and via the second fluid guide structure 26 and possibly via the conveying profiles 13, 17 to the first end face 9 of the rotor 8 (see FIGS. 2 to 8). Then the fluid 18 is forced along the gap 21 between the first end face 9 and the stator 7 and at least along the radial direction 14 through the gap 21 and as a leakage across the gap 21 to the outside (see Fig. 2, 3, 7 and 8) . The fluid 18 then flows as a leak over the second outer peripheral surface 28 of the rotor 8 (ie between the housing 6 and the rotor 8) towards the second end face 22 and the suction side 4 arranged there (see FIGS. 2 and 8). The components shown in Fig. 2 rotor 8 and outer conveyor 11 are together in one piece and thus designed according to the invention.

In the remaining FIGS. 1 and 3 to 8 , which are not according to the invention only in this respect, the rotor 8 comprises two components which are connected to one another via a connection which acts in a form-fitting manner in relation to a circumferential direction 35 . One component of the rotor 8 forms the first end face 9 and includes the magnets 33, the other component includes the outer conveyor 11. At least when the pump assembly 1 is in operation, rotating components (rotor 8, comprising the outer conveyor 11, inner conveyor 15) are the Pump assembly 1 relative to fixed components (housing 6, stator 7, centering element 19) of the pump assembly 1 kontaktff ei arranged. All rotating components are thus moved in the fluid 18 . The fluid 18 prevents contact between see rotating components of the pump arrangement 1 and stationary components of the pump arrangement 1 or ensures a non-contact arrangement.

reference number

1 pump arrangement

2 pump

3 print side

4 suction side

5 drive unit

6 housing

7 stator

8 rotors

9 first face

10 axial direction

11 outside funding

12 inner peripheral surface

13 first conveyor profile

14 radial direction

15 internal funding

16 outer peripheral surface

17 second conveyor profile

18 fluids

19 centering element

20 first fluid guide structure

21 column

22 second face

23 width

24 pressure line

25 first outer peripheral surface

26 second fluid guide structure

27 suction line

28 second outer peripheral surface 29 first axis of rotation

30 second axis of rotation

31 winding

32 core 33 magnet

34 flow pattern

35 circumferential direction

Claims

Patent claims Pump arrangement (1), at least comprising a pump (2) with a pressure side (3) and a suction side (4) and a drive unit (5) for the pump (2), which are arranged in a common housing (6), wherein the drive unit (5) is an axial flow electric drive, which comprises a stator (7) non-rotatably connected to the housing (6) and a rotor (8) arranged rotatably relative to the housing (6), the rotor (8) having is arranged opposite the stator (7) along an axial direction (10) on a first end face (9) and forms an outer conveying means (11) of the pump (2) and has a first conveying profile (13) on an inner peripheral surface (12), wherein An inner conveying means (15) of the pump (2) is arranged in a radial direction (14) inside the rotor (8) and has a second conveying profile (17) on an outer peripheral surface (16) which is connected to the first conveying profile (13). cooperates to convey a fluid (18); the inner conveyor (15) being integral with the housing

(6) non-rotatably connected centering element (19); at least the rotor (8) and the outer conveying means (11) being arranged to do so exclusively via the pump

(2) produced fluid (18) to be stored; at least between the first end face (9) and the stator

(7) a first fluid guide structure (20) is arranged and connected to the pressure side (3), so that during operation of the electric drive a gap (21) between the first end face (9) and the stator (7) through the fluid (18) is producible. Pump arrangement (1) according to claim 1, wherein the rotor (8) extends between the first end face (9) facing the stator (7) and an oppositely arranged second end face (22) along the axial direction (10) over a width (23) extends, the first conveying profile (13) and the second conveying profile (17) each extending across the width (23).

3. Pump arrangement (1) according to one of the preceding claims, wherein the second conveying profile (17) interacts with the first conveying profile (13) to drive the inner conveying means (15), the inner conveying means (15) being rotatable on the centering element (19). is stored; whereby the inner funding (15) exclusively through the pump

(2) funded fluid (18) is stored.

4. Pump assembly (1) according to any one of the preceding claims, wherein the housing (6) on one of the first end face (9) oppositely arranged second end face (22) of the rotor (8) with the pressure side

(3) has a connected pressure line (24), the first fluid guide structure (20) being connected to the pressure line (24) via the centering element (19).

5. Pump arrangement (1) according to claim 4, wherein the inner conveying means (15) is rotatably mounted on a first outer peripheral surface (25) of the centering element (19), wherein a second fluid guide structure (26) for connecting the pressure line (24) to the first fluid guide structure (20) is formed at least partially on the first outer peripheral surface (25).

6. Pump arrangement (1) according to one of the preceding claims, wherein the housing (6) on one of the first end face (9) arranged opposite the second end face (22) of the rotor (8) with the suction side

(4) has a connected suction line (27), with leakage of the fluid from the first fluid guide structure (20) via a second outer peripheral surface (28) of the rotor (8) towards the suction line (27).

7. Pump arrangement (1) according to any one of the preceding claims, wherein the rotor (8) and the outer conveying means (11) are made in one piece. Pump arrangement (1) according to one of the preceding claims, wherein rotating components (8, 11, 15) of the pump arrangement (1) are arranged without contact with respect to stationary components (6, 7, 19) of the pump arrangement (1), at least during operation of the pump arrangement (1). are. Pump arrangement (1) according to one of the preceding patent claims, wherein at least the rotor (8) is produced by powder metallurgy. Pump arrangement (1) according to one of the preceding patent claims, wherein the pump (2) is a gerotor pump or an internal gear pump and the first delivery profile (13) is a first toothing and the second delivery profile (17) is a second toothing, the toothings having different numbers of teeth from one another exhibit; or - is a vane cell or roller cell pump; and wherein a first axis of rotation (29) of the rotor (8) and a second axis of rotation (30) of the inner conveyor (15) are arranged parallel to one another and spaced apart from one another in the radial direction (14).