Pump device

Abstract

The invention relates to a pump device (1) comprising at least a pump (2) with a pressure side (3) and a suction side (4) and a drive unit (5) for the pump (2) arranged in a common housing (6), wherein the drive unit (5) is an axial electric drive comprising a stator (7) which is torsionally fixed to the housing (6) and a rotor (8) which is arranged in a rotatable manner relative to the housing (6), wherein the rotor (8) is arranged opposite the stator (7) along an axial direction (10) with a first end side (9) and forms an outer conveying means (11) of the pump (2) and has a first conveying contour (13) at an inner circumferential face (12) spaced apart from the first end side (9), wherein an inner conveying means (15) of the pump (2) is arranged in the rotor (8) along a radial direction (14) and has a second conveying contour (17) at an outer circumferential face (16) which cooperates with the first conveying contour (13) for conveying a fluid (18).

Description

TECHNICAL FIELD

[0001] The invention relates to a pump device comprising at least a pump and a drive unit for the pump arranged in a common housing. The drive unit is an axial electric drive comprising a stator which is torsionally fixed to the housing and a rotor which is arranged in a rotatable manner relative to the housing. The rotor forms an outer conveying means of the pump and has at an inner circumferential face a first conveying profile, for example a first toothing or a vane of a vane pump, wherein an inner conveying means of the pump is arranged radially within the rotor, which inner conveying means has at an outer circumferential face a second conveying profile, for example a second toothing or a cylindrical outer circumferential face, which second conveying profile cooperates with the first conveying profile for conveying a fluid and, if necessary, for driving the inner conveying means by the rotor in the case of a toothing. BACKGROUND

[0002] In known pump embodiments, the rotor of the pump is arranged on a shaft which is guided out of the housing of the pump device.

[0003] A pump device is known, for example, from DE 10 2015 207 748 A1. There, a fluid pump driven by an electric motor is described. Here, the pump rotor of the fluid pump is coupled to the electric motor. The electric motor is an axial electric motor, the electric motor rotor of which is also the pump rotor or drives the pump rotor. The pump rotor and the electric motor rotor are mounted in a common housing in which the pump rotor and the electric motor rotor are disc-shapedly integrated as a combined rotor rotating, wherein the common housing has a fluid inflow and a fluid outflow to the combined rotor. A pump chamber or fluid conveying chamber is arranged enclosed in the common housing and axially along the axis of rotation to the fluid inflow and the fluid outflow of the pump chamber.

[0004] From DE 10 2017 113 825 A1, a pump device is known which comprises at least a pump and a drive unit for the pump arranged in a common housing. The drive unit is an axial electric drive comprising a stator which is torsionally fixed to the housing and a rotor which is arranged in a rotatable manner relative to the housing. The rotor forms an outer conveying means of the pump, wherein an inner conveying means of the pump is arranged radially within the rotor, which inner conveying means cooperates with the first conveying profile for conveying a fluid and, if necessary, for driving the inner conveying means by the rotor in the case of a toothing. The inner conveying means is arranged on a sleeve. There is no mechanical bearing structure of the outer conveying means and the rotor. In order to set an operation as leak-tight as possible, the side wall surrounding the rotor is set via traction means according to a specific spacing from one another. SUMMARY

[0005] There is always a need to further simplify such a pump and to design such a pump to be robust and durable for operation. In particular, a compact pump device should be proposed, which can be manufactured as simply as possible and which can be operated as wear-free as possible.

[0006] A pump device with the features of claim 1 helps to solve this task. Advantageous design refinements are the subject of the dependent claims. The features mentioned in the claims one by one can be combined with one another in a technically reasonable manner and can be supplemented by the details of the description and / or the drawings, which illustrate further embodiments of the invention, by the elucidations.

[0007] A pump device is proposed, which comprises at least a pump with a pressure side and a suction side arranged in a common housing and a drive unit for the pump. The drive unit is an axial-flow electric drive, which comprises (exactly) one stator which is connected to the housing against rotation and (exactly) one rotor which is arranged in a rotatable manner relative to the housing. The rotor is arranged with a first end side axially opposite to the stator or to the housing on the stator side, i.e. the housing surrounding the stator, and forms an outer conveying means of the pump. The outer conveying means has a first conveying profile at an inner circumferential face. An inner conveying means of the pump is arranged radially within the rotor, which has a second conveying profile at an outer circumferential face, which cooperates with the first conveying profile for conveying the fluid. The conveying means is arranged spaced apart from the first end side. The inner conveying means is supported on a centering element which is connected to the housing against rotation. At least the rotor and the outer conveying means are provided for being supported (in a rotatable manner relative to the other components of the pump device) only by the fluid conveyed via the pump. A first fluid guiding structure is arranged at least between the first end side and the stator (or the housing on the stator side) and is connected to the pressure side, so that in the operation of the pump device a gap can be established between the first end side and the stator (or the housing on the stator side) by the fluid.

[0008] The electric drive generally comprises a stator and a rotor which are arranged coaxially to one another. The rotor is here referred to as a carrier of permanent magnets, the stator has a coil arrangement. In axial-flow motors, the rotor and the stator are arranged in particular one behind the other along the axial direction. Here, differently magnetized magnets are arranged alternately on the rotor in the circumferential direction.

[0009] The coil arrangement of the stator has cores, for example made of SMC, which are surrounded by current-carrying windings. Each core can be an element which is arranged to be magnetized when an electric current flows through the current-carrying windings surrounding the core. The current-carrying windings can be designed as coils.

[0010] SMC is formed, inter alia, from small particles of iron powder that are electrically insulated from one another. The iron losses in SMC components in an alternating electric field are generally low. It therefore seems worthwhile in this respect to expect that SMC will be used in electric machines at least partially in place of the most frequently used steel layers (steel sheets or electrical steel sheets). To form a component made of SMC, the particles are compacted and hardened. The SMC material is not sintered in this case. Rather, tempering below the melting point takes place, but this is sufficient for the material to permanently retain a defined geometry.

[0011] The rotor of the electric drive can have permanent magnets or soft-magnetic elements, for example in the recesses. A permanently excited synchronous or brushless direct-current motor, in short BLDC, can thus be formed as electric drive with permanent magnets, and a reluctance motor can be created as electric motor in axial, radial or transverse design, for example, with soft-magnetic elements.

[0012] The rotor and the stator together form a drive unit, in particular of a pump device.

[0013] The rotor has a first conveying contour (for example a first toothing) at the inner circumferential face, with which the internal conveying means cooperate with a second conveying contour (for example a second toothing) arranged at the outer circumferential face of the internal conveying means to convey the fluid. When the conveying contours are configured as toothings, the internal conveying means are driven by the external conveying means.

[0014] The internal conveying means do not need to be driven themselves, for example by means of an axis of the internal conveying means. The rotor and the internal conveying means together form, inter alia, a pump of a pump device, which conveys the fluid from a suction side or low-pressure side (fluid inlet) toward a pressure side or high-pressure side (fluid outlet).

[0015] Pistonic pumps and rotary pumps are suitable as pump devices. The rotor and the internal conveying means of the pump device are arranged in particular in a manner that is rotatable about a rotation axis. The rotor and the internal conveying means are arranged in particular in a manner that is rotatable about a rotation axis.

[0016] Likewise, vane pumps and roller vane pumps can be used as pump devices, wherein the external conveying means comprise vanes or rollers as first conveying contour, which are movable in the radial direction relative to the rotation axis. The second conveying contour is formed, for example, by a cylindrical outer circumferential face of the internal conveying means, which cooperates with the vanes or rollers.

[0017] The rotor and the conveying means are arranged in particular in a sliding bearing. In the sliding bearing arrangement, in particular in the bearing arrangement acting in the axial direction, a fluid film is formed, which reduces the friction between the different moving components.

[0018] The rotor, in particular together with the outer conveying means, is designed in particular without a shaft or arranged without support or only slidingly supported in relation to the radial direction.

[0019] In the operation of the axial-flow electric drive, forces occur in the axial direction which urge the rotor to be drawn onto the stator. In the embodiment with only one stator proposed here for a compact pump device, these forces can cause the rotating rotor to come into contact with the stator or with the housing surrounding the stator. This problem is exacerbated in pump devices in which the rotor is not arranged on a shaft or arranged without support in relation to the radial direction, since a shaftless rotor can easily tilt in operation. In the arrangement of the rotor which is only slightly bent (the end sides of the rotor cannot normally be produced exactly perpendicular to the axis of rotation), a partial contact between the rotor and the housing or the stator can occur. Here, a material-removing action of the rotor on the housing or the stator can occur, since this can permanently damage the pump device and significantly reduce its service life.

[0020] In the current pump devices, the tilting of the rotor is prevented or reduced in particular by the greatest possible diameter of the faces of the rotor which act as bearings in relation to the axial direction.

[0021] It is proposed here that a fluid-conducting structure is arranged between the first end side of the rotor and the stator or the stator-side housing and is connected to the pressure side, so that a gap can be established by the fluid between the first end side and the stator or the stator-side housing in the operation of the pump device. The pressure set by the pump device on the pressure side is used here to set and maintain the axial spacing between the first end side and the stator or the housing.

[0022] The spacing between the electromagnetic rotor part (magnet) and the electromagnetic stator part is in particular approximately 0.5 mm and is in particular not significantly influenced by the fluid. The spacing which is produced and formed by the fluid between the rotor and the stator or the stator-side housing in the operation of the pump device is in particular only provided to prevent friction between the components and thus to prevent wear. The gap, i.e. the spacing formed by the fluid, is in particular significantly smaller than the spacing between the electromagnetic components of the rotor and the stator.

[0023] The first fluid-conducting structure in particular comprises a channel structure which is configured at least on the surfaces forming the gap. These surfaces are formed at least by the first end side of the rotor and by the wall of the stator or the housing which is opposite the first end side. In particular, there is no gap with a constant gap size, but the gap size can vary locally as a result of the channel structure designed on at least one surface. The fluid can be conveyed through the channel structure in particular at least radially through the gap (and beyond the gap). Here, in particular at least one flow channel for the fluid is provided along which the fluid is conveyed through the gap (and beyond the gap).

[0024] The fluid is in particular to be delivered substantially into the gap in order to reduce the friction between the components there. The delivery of fluid beyond the gap is in particular only an unavoidable evil in order to deliver fluid into the gap. The fluid is in particular not to be delivered purposefully outside the gap, but rather internal leakage is to be kept as low as possible.

[0025] A substantially constant pressure of the fluid is in particular provided along the extension of the first fluid-conducting structure or along the channel structure in the gap. There is in particular no throttling section along the first fluid-conducting structure or along the flow channel of the channel structure, which would cause a gradual or continuous pressure drop. Here, it is entirely possible for there to be a throttled pressure between different flow channels of the channel structure.

[0026] The pump device is in particular designed in such a way that the axial forces acting between the stator and the rotor are (exactly) compensated by the fluid pressure generated in the pump device during operation at the pressure side. The fluid pressure present in the gap between the rotor and the stator can be set, if necessary, by a (adjustable or constant) throttle valve.

[0027] The rotor extends in particular in the axial direction between a first end side facing the stator and an oppositely arranged second end side through a first width, wherein the first delivery profile and the second delivery profile each extend through a smaller second width. The delivery profiles in particular have the same width, so that the end sides of the inner and outer delivery means can be arranged flush with one another in the radial direction.

[0028] The second delivery profile in particular cooperates with the first delivery profile to drive the inner delivery means, wherein the inner delivery means is rotatably supported on the centering element. Here, the inner delivery means is also supported only by the fluid delivered via the pump.

[0029] The gap between the rotor and the stator is in particular formed only by the first end side of the rotor and not by the outer or inner delivery means. The delivery means is arranged spaced apart from the first end side in the axial direction. The delivery means in particular extends to the second end side of the rotor. The rotor is thus in particular configured in the shape of a disc. The first fluid-conducting structure can thus be arranged on a large face, so that a large axial force generated in the operation of the electric drive can be compensated with fluid on said large face.

[0030] The housing in particular has a pressure line connected to the pressure side of the pump device at the second end side of the rotor, which is arranged opposite the first end side. The first fluid-conducting structure is in particular connected to the pressure line (only) via the centering element and / or via the delivery profiles.

[0031] The fluid is conveyed from the pressure line, in particular exclusively, via the centering element, toward the first fluid-conducting structure.

[0032] The rotor has, in particular, exclusively one through-opening which extends at least in the axial direction, through which the fluid is conveyed from the pressure line or from the pressure side toward the first fluid-conducting structure. The through-opening has, in particular, a maximum opening cross section which has at most 2%, preferably at most 1%, particularly preferably at most 0.5%, of the area of the first end side of the rotor.

[0033] The first fluid-conducting structure is connected to the pressure line, in particular exclusively, via the at least one through-opening.

[0034] The inner conveying means are supported, in particular in a rotatable manner, on the first outer circumferential surface of the centering element, wherein the second fluid-conducting structure is at least partially configured on the first outer circumferential surface in order to connect the pressure line to the first fluid-conducting structure. It is thus possible, in particular, to form a hydrodynamic or hydrostatic bearing of the inner conveying means on the centering element.

[0035] The second fluid-conducting structure is configured, in particular, in the type of the first fluid-conducting structure, wherein the second fluid-conducting structure is provided for producing a gap which extends parallel to the axis of rotation between the centering element and the inner conveying means.

[0036] The housing has, in particular, at the second end side of the rotor which is arranged opposite the first end side, a suction line which is connected to the suction side. The transfer of the fluid from the first fluid-conducting structure to the suction line, which will be referred to as leakage, is accomplished, in particular, by means of the second outer circumferential surface of the rotor. This leakage is used, in particular, for lubricating the mutually opposite surfaces of the rotor and the housing.

[0037] With the pump device, fluid can be conveyed from the suction line toward the pressure line via the conveying contour. The amount of fluid for lubricating and bearing parts and for ensuring the gap can flow at least partially (as leakage) from the pressure side via the gap toward the suction side (back).

[0038] The fluid is conveyed, in particular, from the pressure side via the centering element and via the second fluid-conducting structure and via the through-opening toward the first end side of the rotor. The fluid is conveyed, in particular, (then but particularly exclusively as leakage) along the gap between the first end side and the stator and at least radially outwardly over the gap. The fluid (then) flows via the second outer circumferential surface of the rotor (i.e. between the housing and the rotor) toward the second end side and toward the suction side arranged there.

[0039] The rotor and the outer conveying means are designed, in particular, in two parts, preferably made in two parts, i.e. separately from one another. The rotor and the outer conveying means are connected to one another, in particular, torsionally. The connection can be established, for example, by means of a connecting element, for example by means of a dowel, a screw structure, etc.

[0040] At least the components of the pump device which rotate during operation of the pump device (rotor, outer conveying means, inner conveying means) are arranged contactlessly, in particular, with respect to the stationary components of the pump device (housing, stator, centering element). In particular, no mechanical contact exists between the rotating components of the pump device and the stationary components of the pump device during operation of the pump device.

[0041] All rotating components are operated in particular in a fluid. In particular, the contact between the rotating components of the pump device and the stationary components of the pump device is prevented by the fluid or the contactless arrangement is ensured.

[0042] In particular, the tolerances of components which would otherwise have to be manufactured with high precision can be softened, so that the costs for manufacturing the pump device can be reduced. The perpendicularity which is generally required between the rotational axis and the first end side is in particular implemented here with less precision, since the gap between the rotor and the housing or the stator is ensured by the fluid.

[0043] In such a pump device, the parallelism of the end sides of the rotor is a remaining important tolerance which has to be implemented very precisely. These can all be manufactured more cost-effectively (for example by double-disc grinding).

[0044] At least the rotor is manufactured in particular by means of powder metallurgy. At least the stator is manufactured in particular by means of powder metallurgy. The rotor is in particular also manufactured by means of sintering.

[0045] It is preferred that the pump

[0046] is a gerotor pump or an internal gear pump (also called crescent gear pump) and the first conveying contour is a first toothing and the second conveying contour is a second toothing, wherein the toothing has a different number of teeth from one another; or

[0047] is a vane pump or a roller vane pump;

[0048] wherein the first rotational axis of the rotor and the second rotational axis of the inner conveying means are parallel to one another and arranged radially spaced apart from one another.

[0049] The pump device has in particular only static sealing structures, i.e. sealing structures which are arranged only between components of the anti-rotation arrangement. A secure and durable sealing can thus be ensured by only static sealing structures.

[0050] The pump device has in particular the following operating parameters:

[0051] - nominal power consumption in watts: 0 to 2000; preferably 50 to 200;

[0052] - nominal maximum operating pressure in bars: 0 to 100; preferably 4 to 12;

[0053] - volumetric power in l / min: 0 to 50; preferably 3 to 12;

[0054] - rotational speed of the rotor in rpm: 0 to 7000; preferably 1000 to 4000.

[0055] The gap between the first end side of the rotor, in particular not in the range of the magnet, and the housing or stator, i.e. in particular the gap forming the plain bearing or the gap formed by the first fluid guiding structure, is in particular at least 0.003 mm, preferably at most 0.1 mm, particularly preferably at most 0.05 mm or even at most 0.01 mm in the pump device operation.

[0056] The gap between the magnet and the housing or stator is in particular at least 0.2 mm, preferably at least 0.3 mm. The gap is at most 1.5 mm, particularly preferably at most 1.0 mm, in particular 0.3 to 0.7 mm in this range.

[0057] The use of the indefinite article ("a", "an", "one") in particular in the claims and in the specification reproducing these claims is thus not to be understood as a numeral. The terms or components introduced with these indefinite articles can thus be understood in such a way that these terms or components occur at least once, but can in particular also occur multiple times.

[0058] With caution, it is noted that the numerals used herein ("first", "second",...) are mainly (only) used to distinguish a plurality of identical objects, quantities or processes, i.e. in particular not to define the mutual relationship and / or sequence of these objects, quantities or processes. If a mutual relationship and / or sequence is intended, this is explicitly stated herein or is apparent to the person skilled in the art from the design solution described in detail. Insofar as components can occur multiple times ("at least once"), the specification of one of these components also applies to all or a part of these components, but this is not mandatory. BRIEF DESCRIPTION OF DRAWINGS

[0059] The application and the technical field are explained in more detail below with the aid of the drawings. It is pointed out that the application is not to be restricted to the embodiments listed. Insofar as this is not explicitly shown otherwise, it is in particular possible to extract some partial aspects of the facts explained in the drawings and to combine them with other components and knowledge from the current specification. In particular, it is pointed out that the drawings and in particular the dimensions shown are only schematic.

[0060] Figure 1 The pump device is shown in an exploded view in perspective;

[0061] Figure 2The side view shows the press in the section. Figure 1 The pump device; and

[0062] Figure 3 The rotor of the pump unit is shown in a perspective view;

[0063] Figure 4 The pump assembly and the flow direction from the pressure side to the first end side are shown in the side view in section.

[0064] Figure 5 A portion of the pump assembly and its components are shown in the perspective view. Figure 4 Part of the flow direction;

[0065] Figure 6 A portion of the pump assembly and its components are shown in the perspective view. Figure 4 Another part of the flow direction, which is immediately followed by... Figure 5 The direction of flow;

[0066] Figure 7 The three-dimensional view shows the press Figure 4 Part of the pump unit;

[0067] Figure 8 A portion of the pump assembly and its components are shown in the perspective view. Figure 4 A portion of the flow direction and the immediate following flow direction Figure 6 Another part of the flow direction; and

[0068] Figure 9 The section shown in the perspective view is pressed... Figure 2 Pump device. Detailed Implementation

[0069] Figure 1 Pump assembly 1 is shown in an exploded view in a perspective view. Figure 2 The pump unit 1 is shown in the side view in section. Figure 3 The rotor 8 of the pump unit 1 is shown in the perspective view. Figure 4 The pump assembly 1 and the flow path 34 from the pressure side 3 to the first end side 9 are shown in the side view in section. Figure 5 A portion of the pump unit 1 and its assembly are shown in the perspective view. Figure 4 The flow direction is part of 34. Figure 6 A portion of the pump assembly 11 and its components are shown in the perspective view. Figure 4 The flow direction followed immediately by Figure 5 The flow is directed towards another part of 34. Figure 7 The three-dimensional view shows the press Figure 4 It is part of the pump unit 1. Figure 8A part of the pump device 1 and a part of the flow course 34 according to Figure 4 and a further part of the flow course 34 according to Figure 6 are shown in a perspective view. Figure 9 The pump device 1 according to Figure 2 is shown in a perspective view in a sectional plane. The following is explained jointly. Figures 1 to 9

[0070] The pump device 1 comprises a pump 2 with a pressure side 3 and a suction side 4 and a drive unit 5 for the pump 2 arranged in a common housing 6. The drive unit 5 is an axial-flow electric drive which comprises exactly one stator 7 which is connected to the housing 6 against rotation and exactly one rotor 8 which is arranged in a manner rotatable relative to the housing 6. The rotor 8 is arranged opposite the stator 7 along an axial direction 10 with a first end side 9 and forms an outer conveying means 11 of the pump 2. The outer conveying means 11 has a first conveying contour 13 at an inner circumferential face 12. An inner conveying means 15 of the pump 2 is arranged in the rotor 8 along a radial direction 14, which inner conveying means has a second conveying contour 17 at an outer circumferential face 16 which cooperates with the first conveying contour 13 to convey a fluid 18. The conveying means 11, 15 are arranged spaced apart from the first end side 9. The inner conveying means 15 is supported on a centering element 19 which is connected to the housing 6 against rotation. The rotor 8 and the outer conveying means 11 are supported in a manner rotatable relative to the other components of the pump device 1 only via the fluid 18 conveyed by the pump 2. A first fluid guide structure 20 is arranged between the first end side 9 and the stator 7 and is connected to the pressure side 3, so that in the operation of the electric drive a gap 21 can be established between the first end side 9 and the stator 7 by the fluid 18.

[0071] The coil arrangement of the stator 7 has a core 32, for example made of SMC, which is surrounded by a current-carrying winding 31.

[0072] The rotor 8 of the electric drive has a magnet 33. The core 32 and the winding 31 are arranged spaced apart from the magnet 33 by a gap 31.

[0073] The rotor 8 has a first conveying contour 13, here a first toothing, at the inner circumferential face 12, with which the inner conveying means 15 cooperates with a second conveying contour 17, here a second toothing, arranged at the outer circumferential face 16 of the inner conveying means 15 to convey the fluid 18. When the conveying contours 13, 17 are configured as toothing, the inner conveying means 15 is driven by the outer conveying means 11. A first rotational axis 29 of the rotor 8 (and of the outer conveying means 11) and a second rotational axis 30 of the inner conveying means 15 are arranged parallel to one another and spaced apart from one another along the radial direction 14. The pump 2 is designed as an oscillating-piston pump.

[0074] ​In the axial direction 10 a force occurs which urges the rotor 8 to be drawn onto the stator 7 in the axial direction 10. By means of the first fluid guiding structure 20 which is arranged between the first end side 9 and the stator 7 and which is connected to the pressure side 3, a gap 21 is set between the first end side 9 and the stator 7 by means of the fluid 18 during the electric drive operation. The pressure which is set by the pump device 1 on the pressure side 3 by means of the fluid 18 serves here for setting and maintaining the axial distance between the first end side 9 and the stator 7 or the housing 6.

[0075] The rotor 8 extends in the axial direction 10 between the first end side 9 facing the stator 7 and the second end side 22 arranged opposite, through a first width 23, wherein the first conveying profile 13 and the second conveying profile 17 each extend through a second, smaller width 34.

[0076] The gap 21 between the rotor 8 and the stator 7 is formed exclusively by the first end side 9 of the rotor 8 and not by the conveying means 11, 15. The conveying means 11, 15 are arranged spaced apart from the first end side 9 in the axial direction 10. The conveying means 11, 15 extend to the second end side 22 of the rotor 8. The rotor 8 is configured in the shape of a disc.

[0077] The rotor 8 has a through-opening 35 which extends in the axial direction 10, through which the fluid 18 can be conveyed from the pressure line 24 or from the pressure side 3 towards the fluid guiding structure 20 along a flow run 38 (cf. Figure 4 , 8 , 9). The through-opening 35 has a maximum opening cross section 36.

[0078] The housing 6 has a pressure line 24 connected to the pressure side 3 at the second end side 22 of the rotor 8 which is arranged opposite the first end side 9, wherein the first fluid guiding structure 20 is connected to the pressure line 24 via the through-opening 35 and the centering element 19 and / or via the conveying profiles 13, 17.

[0079] The fluid 18 is conveyed from the pressure line 24 via the centering element 19 and the through-opening 35 towards the first fluid guiding structure 20 along a flow run 39 (cf. Figure 4 , 8 , 9).

[0080] The inner conveying means 15 is rotatably supported on the first outer circumferential face 25 of the centering element 19, wherein the second fluid guiding structure 26 is configured for connecting the pressure line 24 to the first fluid guiding structure 20 on the first outer circumferential face 25 (cf. Figures 4 to 6 and 8, 9).

[0081] The housing 6 has a suction line 27 connected with the suction side 4 at a second end side 22 of the rotor 8 arranged opposite the first end side 9, wherein a leakage of fluid from the first fluid guiding structure 20 via the second outer circumferential face 28 of the rotor 8 towards the suction line 27 occurs (cf. Figure 9 ).

[0082] The fluid 18 is fed from the pressure line 24 via the centering element 19 and via the second fluid guiding structure 26 and via the through opening 35 and if necessary via the delivery profile 13, 17 towards the first end side 9 of the rotor 8 (cf. Figure 4 , 8 and 9). The fluid 18 is then fed outwards along the gap 21 between the first end side 9 and the stator 7 and at least along the radial direction 14 through and over the gap 21 (cf. Figure 4 , 8 , 9). The fluid 18 then flows as a leakage via the second outer circumferential face 28 of the rotor 8, i.e. between the housing 6 and the rotor 8, towards the second end side 22 and towards the suction side 4 arranged there (cf. Figure 4 and 9 ).

[0083] The rotor 8 and the outer delivery means 11 are designed in two parts, i.e. are made in two parts or are manufactured separately from one another. The rotor 8 (or the disc-shaped part of the rotor 8) and the outer delivery means 11 are connected to one another in a torque-proof manner for the construction of the rotor 8. The connection is established by a connecting element 37, here by a dowel.

[0084] At least during the operation of the pump device 1, the rotating components (rotor 8, outer delivery means 11, inner delivery means 15) of the pump device 1 are arranged contactlessly relative to the stationary components (housing 6, stator 7, centering element 19) of the pump device 1. All rotating components are thus moved in the fluid 18. Contact between the rotating components of the pump device 1 and the stationary components of the pump device 1 is prevented by the fluid 18 or a contactless arrangement is ensured.

[0085] List of reference signs

[0086] 1 pump device

[0087] 2 pump

[0088] 3 pressure side

[0089] 4 suction side

[0090] 5 drive unit

[0091] 6 housing

[0092] 7 stator

[0093] 8 rotor

[0094] 9 first end side

[0095] 10 axial

[0096] 11 outer conveying means

[0097] 12 inner circumferential surface

[0098] 13 first conveying profile

[0099] 14 radial

[0100] 15 inner conveying means

[0101] 16 outer circumferential surface

[0102] 17 second conveying profile

[0103] 18 fluid

[0104] 19 centering element

[0105] 20 first fluid guiding structure

[0106] 21 gap

[0107] 22 second end side

[0108] 23 first width

[0109] 24 pressure line

[0110] 25 first outer circumferential surface

[0111] 26 second fluid guiding structure

[0112] 27 suction line

[0113] 28 second outer circumferential surface

[0114] 29 first rotational axis

[0115] 30 second rotational axis

[0116] 31 winding

[0117] 32 core

[0118] 33 magnet

[0119] 34 second width

[0120] 35 through opening

[0121] 36 opening cross section

[0122] 37 connecting means

[0123] 38 flow direction

[0124] 39 circumferential direction

Claims

1. A pump assembly (1), comprising at least a pump (2) having a pressure side (3) and a suction side (4) arranged in a common housing (6) and a drive unit (5) for said pump (2), wherein, The drive unit (5) is an axial-flow electric drive, which includes a stator (7) torsionally connected to the housing (6) and a rotor (8) arranged rotatably relative to the housing (6). The rotor (8) is arranged axially (10) opposite the stator (7) with a first end side (9) and forms an external conveying device (11) of the pump (2) and a first conveying profile (13) at an inner circumferential surface (12). An internal conveying device (15) of the pump (2) is arranged radially (14) inside the rotor (8), and the internal conveying device has a second conveying profile (17) at an outer circumferential surface (16). The second conveying profile is related to the first... A conveying profile (13) is configured to convey fluid (18), wherein conveying devices (11, 15) are spaced apart from the first end side (9), wherein the inner conveying device (15) is supported on a centering element (19) that is torsionally connected to the housing (6); wherein at least the rotor (8) and the outer conveying device (11) are configured to be supported only by fluid (18) conveyed via the pump (2), wherein a first fluid guiding structure (20) is arranged at least between the first end side (9) and the stator (7) and connected to the pressure side (3), thereby allowing a gap (21) to be established between the first end side (9) and the stator (7) by the fluid (18) during operation of the electric drive. The rotor (8) extends along the axial direction (10) through a first width (23) between a first end side (9) facing the stator (7) and a second end side (22) opposite to it. The first conveying profile (13) and the second conveying profile (17) extend through a smaller second width (34). The conveying profiles (13, 17) are arranged spaced apart from the first end side (9) along the axial direction (10).

2. The pump device (1) according to claim 1, wherein, The second conveying profile (17) cooperates with the first conveying profile (13) to drive the internal conveying device (15), wherein the internal conveying device (15) is rotatably supported on the centering element (19), and wherein the internal conveying device (15) is also supported only by the fluid (18) conveyed via the pump (2).

3. The pump device (1) according to claim 1, wherein, The housing (6) has a pressure line (24) connected to the pressure side (3) at a second end side (22) of the rotor (8) opposite to the first end side (9), wherein the first fluid guiding structure (20) is connected to the pressure line (24) via the centering element (19).

4. The pump device (1) according to claim 3, wherein, The internal delivery device (15) is rotatably supported on the first outer circumferential surface (25) of the centering element (19), wherein the second fluid guiding structure (26) is at least partially constructed on the first outer circumferential surface (25) for connecting the pressure line (24) to the first fluid guiding structure (20).

5. The pump device (1) according to claim 1, wherein, The housing (6) has a suction line (27) connected to the suction side (4) at a second end side (22) of the rotor (8) opposite to the first end side (9), wherein fluid leaks from the first fluid guiding structure (20) toward the suction line (27) via the second outer circumferential surface (28) of the rotor (8).

6. The pump device (1) according to claim 1, wherein, The rotor (8) and the external conveying device (11) are designed to consist of two parts, but are connected to each other in a torsionally resistant manner.

7. The pump device (1) according to claim 1, wherein, The components (8, 11, 15) of the pump device (1) that rotate during operation of the pump device (1) are arranged without contact with the fixed components (6, 7, 19) of the pump device (1).

8. The pump device (1) according to claim 1, wherein, The rotor (8) has a through opening (35) extending at least along the axial direction (10), through which fluid (18) can be transported from the pressure side (3) toward the first fluid guiding structure (20), wherein the through opening (35) has a maximum opening cross-section (36) having a maximum area of ​​2% of the area of ​​the first end side (9) of the rotor (8).

9. The pump device (1) according to claim 1, wherein, The pump (2) - is a cycloidal pump or an internal gear pump and the first delivery profile (13) is a first geared section and the second delivery profile (17) is a second geared section, wherein the geared sections have different numbers of teeth from each other; or - It is a vane pump or a roller vane pump; Furthermore, the first rotation axis (29) of the rotor (8) and the second rotation axis (30) of the internal conveying device (15) are arranged parallel to each other and spaced apart from each other along the radial direction (14).

Images