Pump Arrangement

Abstract

A pump arrangement (1) at least comprising a pump (2) having a pressure side (3) and an intake 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) which is connected to the housing (6) in a rotationally secure manner and a rotor (8) which is arranged so as to be able to be rotated with respect to the housing (6), wherein the rotor (8) is arranged with a first end face (9) opposite the stator (7) in an axial direction (10) and forms an outer conveying means (11) of the pump (2) and has with spacing from the first end face (9) on an inner circumferential face (12) a first conveying profile (13), wherein in a radial direction (14) inside the rotor (8) there is arranged an inner conveying means (15) of the pump (2) which has on an outer circumferential face (16) a second conveying profile (17) which cooperates with the first conveying profile (13) in order to convey a fluid (18).

Claims

1. A pump arrangement comprising a pump having a pressure side and an intake side and a drive unit for the pump which are arranged in a common housing, wherein the drive unit is an axial flow electric drive which comprises a stator which is connected to the housing in a rotationally secure manner and a rotor which is arranged so as to be able to be rotated with respect to the housing, wherein the rotor is arranged with a first end face opposite the stator in an axial direction and forms an outer conveying means of the pump and has on an inner circumferential face a first conveying profile, wherein in a radial direction inside the rotor there is arranged an inner conveying means of the pump which has on an outer circumferential face a second conveying profile which cooperates with the first conveying profile in order to convey a fluid; wherein the conveying means are arranged with spacing from the first end face; wherein the inner conveying means is supported on a centering element which is connected to the housing in a rotationally secure manner; wherein at least the rotor and the outer conveying means are configured to be supported exclusively via the fluid conveyed by the pump; wherein at least between the first end face and the stator a first fluid guiding structure is arranged and connected to the pressure side so that during operation of the electric drive a gap between the first end face and the stator is producible by the fluid.

2. The pump arrangement as claimed in claim 1, wherein the rotor extends between the first end face facing the stator and a second end face which is arranged opposite in the axial direction over a first width, wherein the first conveying profile and the second conveying profile each extend over a smaller second width, wherein the conveying profiles are arranged in the axial direction with spacing from the first end face.

3. The pump arrangement as claimed in claim 1, wherein the second conveying profile cooperates with the first conveying profile in order to drive the inner conveying means, wherein the inner conveying means is rotatably supported on the centering element; wherein the inner conveying means is also supported exclusively by the fluid conveyed by the pump.

4. The pump arrangement as claimed in claim 1, wherein the housing has at a second end face, which is arranged opposite the first end face, of the rotor a pressure line which is connected to the pressure side, wherein the first fluid guiding structure is connected to the pressure line via the centering element.

5. The pump arrangement as claimed in claim 4, wherein the inner conveying means is rotatably supported on a first outer circumferential face of the centering element, wherein a second fluid guiding structure for connecting the pressure line to the first fluid guiding structure is formed at least partially on the first outer circumferential face.

6. The pump arrangement as claimed in claim 1, wherein the housing has at a second end face, which is arranged opposite the first end face, of the rotor an intake line which is connected to the intake side, wherein a leakage of the fluid from the first fluid guiding structure s carried out via a second outer circumferential face of the rotor in the direction toward the intake line.

7. The pump arrangement as claimed in claim 1, wherein the rotor and the outer conveying means are configured in two pieces but are connected to each other in a rotationally secure manner.

8. The pump arrangement as claimed in claim 1, wherein at least components, which rotate during operation of the pump arrangement, of the pump arrangement are arranged in a contact-free manner with respect to fixed components of the pump arrangement.

9. The pump arrangement as claimed in claim 1, wherein the rotor has a through-opening which extends at least in the axial direction and via which the fluid is conveyable from the pressure side toward the first fluid guiding structure, wherein the through-opening has a largest opening cross section which has a maximum of two percent of the surface-area of the first end face of the rotor.

10. The pump arrangement as claimed in claim 1, wherein the pump is a gerotor pump or an internal gear pump and the first conveying profile is a first tooth arrangement and the second conveying profile is a second tooth arrangement, wherein the tooth arrangements have mutually different numbers of teeth; or is a vane cell pump or a roller cell pump; and wherein a first rotation axis of the rotor and a second rotation axis of the inner conveying means are arranged parallel with each other and spaced apart from each other in the radial direction.

Description

[0062] The invention and the technical environment are explained in greater detail below with reference to the appended Figures. It should be noted that the invention is not intended to be limited by the embodiments which are set out. In particular, unless otherwise explicitly set out, it is also possible to extract partial aspects of the content explained in the Figures and to combine them with other components and findings from the present description. In particular, it should be noted that the Figures and in particular the size relationships illustrated are only schematic. In the drawings:

[0063] FIG. 1: shows a pump arrangement as an exploded perspective illustration;

[0064] FIG. 2: shows a side view of the pump arrangement according to FIG. 1 in cross section; and

[0065] FIG. 3: shows the rotor of the pump arrangement as a perspective view;

[0066] FIG. 4: shows the pump arrangement as a side view in section with the flow path from the pressure side to the first end face;

[0067] FIG. 5: shows a portion of the pump arrangement as a perspective view with a portion of the flow path according to FIG. 4;

[0068] FIG. 6: shows a portion of the pump arrangement as a perspective view with another portion of the flow path, according to FIG. 4, which adjoins the flow path according to FIG. 5;

[0069] FIG. 7: shows a portion of the pump arrangement according to FIG. 4 as a perspective view;

[0070] FIG. 8: shows a portion of the pump arrangement as a perspective view with the portion of the flow path according to FIG. 4 and another portion of the flow path which adjoins the flow path according to FIG. 6; and

[0071] FIG. 9: shows the pump arrangement according to FIG. 2 as a perspective sectioned view.

[0072] FIG. 1 shows a pump arrangement 1 as an exploded perspective view. FIG. 2 shows a pump arrangement 1 as a sectioned side view. FIG. 3 shows the rotor 8 of the pump arrangement 1 as a perspective view. FIG. 4 shows the pump arrangement 1 as a sectioned side view with the flow path 34 from the pressure side 3 to the first end face 9. FIG. 5 shows a portion of the pump arrangement 1 as a perspective view with a portion of the flow path 34 according to FIG. 4. FIG. 6 shows a portion of the pump arrangement 1 as a perspective view with another portion of the flow path 34, according to FIG. 4, which adjoins the flow path 34 according to FIG. 5. FIG. 7 shows a portion of the pump arrangement 1 according to FIG. 4 as a perspective view. FIG. 8 shows a portion of the pump arrangement 1 as a perspective view with the portion of the flow path 34 according to FIG. 4 and another portion of the flow path 34 which adjoins the flow path 34 according to FIG. 6. FIG. 9 shows the pump arrangement 1 according to FIG. 2 as a sectioned perspective view. FIGS. 1 to 9 are described together below.

[0073] The pump arrangement 1 comprises a pump 2 having a pressure side and an intake 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 comprises precisely one stator 7 which is connected to the housing 6 in a rotationally secure manner and precisely one rotor 8 which is arranged so as to be able to be rotated relative to the housing 6. The rotor 8 is arranged with a first end face 9 opposite the stator 7 in an axial direction 10 and forms an outer conveying means 11 of the pump 2. The outer conveying means 11 has on an inner circumferential face 12 a first conveying profile 13. In a radial direction 14 inside the rotor 8 there is arranged an inner conveying means 15 of the pump 2 which has on an outer circumferential face 16 a second conveying profile 17 which cooperates with the first conveying profile 13 in order to convey a fluid 18. The conveying means 11, 15 are arranged with spacing from the first end face 9. The inner conveying means 15 is supported on a centering element 19 which is connected to the housing 6 in a rotationally secure manner. The rotor 8 and the outer conveying means 11 are rotatably supported with respect to other components of the pump arrangement 1 exclusively by means of the fluid 18 which is conveyed by the pump 2. Between the first end face 9 and the stator 7 a first fluid guiding structure 20 is arranged and connected to the pressure side 3 so that during operation of the electric drive a gap 21 can be produced between the first end face 9 and the stator 7 by the fluid 18.

[0074] The coil arrangement of the stator 7 has cores 32, for example, which are made of SMC and which are surrounded by current-carrying windings 21.

[0075] The rotor 8 of the electric drive has magnets 33. Cores 32 and windings 31 are arranged with spacing with respect to the magnets 33 by means of the gap 21.

[0076] The rotor 8 has on the inner circumferential face 12 a first conveying profile 13 (in this instance, a first tooth arrangement) via which the inner conveying means 15 cooperates with the second conveying profile 17 (in this instance, a second tooth arrangement) arranged on the outer circumferential face 16 of the inner conveying means 15 in order to convey the fluid 18. When the conveying profiles 13, 17 are in the form of tooth arrangements, the inner conveying means 15 is driven by the outer conveying means 11. A first rotation axis 29 of the rotor 8 (and the outer conveying means 11) and a second rotation axis 30 of the inner conveying means 15 are arranged parallel with each other and spaced apart from each other in the radial direction 14. The pump 2 is in the form of a gerotor pump.

[0077] During operation of the axial flow electric drive, forces which bring about an attraction of the rotor 8 in the axial direction 10 toward the stator 7 occur in the axial direction 10. As a result of the first fluid guiding structure 20 which is arranged between the first end face 9 and the stator 7 and which is connected to the pressure side 3, during operation of the electric drive a gap 21 is adjusted between the first end face 9 and the stator 7 by the fluid 18. The pressure of the fluid 18 adjusted by the pump arrangement 1 on the pressure side 3 is used in this instance to adjust and maintain the spacing in the axial direction 10 between the first end face 9 and the stator 7 or the housing 6.

[0078] The rotor 8 extends between a first end face 9 facing the stator 7 and a second end face 22 which is arranged opposite in the axial direction 10 via a first width 23, wherein the first conveying profile 13 and the second conveying profile 17 extend in each case over a smaller second width 34.

[0079] The gap 21 between the rotor 8 and stator 7 is formed exclusively by the first end face 9 of the rotor 8 and not by the conveying means 11, 15. The conveying means 11, 15 are arranged in the axial direction 10 with spacing from the first end face 9. The conveying means 11, 15 extend as far as the second end face 22 of the rotor 8. The rotor 8 is constructed in a disk-like manner.

[0080] The rotor 8 has a through-opening 35 which extends in the axial direction 10 and via which fluid 18 can be conveyed from the pressure line 24 or from the pressure side 3 in the direction toward the first fluid guiding structure 20 along the flow path 38 (see FIGS. 4, 8, 9). The through-opening 35 has a greatest opening cross section 36.

[0081] The housing 6 has at a second end face 22, which is arranged opposite the first end face 9, of the rotor 8 a pressure line 24 which is connected to the pressure side 3, 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.

[0082] The fluid 18 is conveyed from the pressure line 24 via the centering element 19 and the through-opening 35 toward the first fluid guiding structure 20 along the flow path 38 (see FIGS. 4, 8, 9).

[0083] The inner conveying means 15 is rotatably supported on a first outer circumferential face 25 of the centering element 19, wherein a second fluid guiding structure 26 is constructed to connect the pressure line 24 to the first fluid guiding structure 20 on the first outer circumferential face (see FIGS. 4 to 6 and 8, 9).

[0084] The housing 6 has at a second end face 22, which is arranged opposite the first end face 9, of the rotor 8 an intake line 27 which is connected to the intake side 4, wherein leakage of the fluid from the first fluid guiding structure 20 is carried out via a second outer circumferential face 28 of the rotor 8 in the direction toward the intake line 27 (see FIG. 9).

[0085] The fluid 18 is conveyed 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 where applicable via the conveying profiles 13, 17 in the direction toward the first end face 9 of the rotor 8 (see FIGS. 4, 8 and 9). The fluid 18 is then conveyed along the gap 21 between a first end face 9 and stator 7 and at least in the radial direction 14 through the gap 21 and as a leakage beyond the gap 21 toward the outer side (see FIGS. 4, 8, 9). The fluid 18 then flows as a leakage via the second outer circumferential face 28 of the rotor 8 (that is to say, between the housing 6 and rotor 8) toward the second end face 22 and to the intake side 4 which is arranged at that location (see FIGS. 4 and 9).

[0086] The rotor 8 and the outer conveying means 11 are constructed in two pieces, that is to say, produced in two pieces or separately from each other. The rotor 8 (or the disk-like portion of the rotor 8) and the outer conveying means 11 are connected to each other in a rotationally secure manner in order to form the rotor 8. The connection is produced by means of connection elements 37, in this instance by means of dowel pins.

[0087] At least during operation of the pump arrangement 1, rotating components (rotor 8, outer conveying means 11, inner conveying means 15) of the pump arrangement 1 are arranged in a contact-free manner with respect to fixed components (housing 6, stator 7, centering element 19) of the pump arrangement 1. All the rotating components are consequently moved in the fluid 18. As a result of the fluid 18, contact between rotating components of the pump arrangement 1 and fixed components of the pump arrangement 1 is prevented or a contact-free arrangement is ensured.

LIST OF REFERENCE NUMERALS

[0088] 1 Pump arrangement [0089] 2 Pump [0090] 3 Pressure side [0091] 4 Intake side [0092] 5 Drive unit [0093] 6 Housing [0094] 7 Stator [0095] 8 Rotor [0096] 9 First end face [0097] 10 Axial direction [0098] 11 Outer conveying means [0099] 12 Inner circumferential face [0100] 13 First conveying profile [0101] 14 Radial direction [0102] 15 Inner conveying means [0103] 16 Outer circumferential face [0104] 17 Second conveying profile [0105] 18 Fluid [0106] 19 Centering element [0107] 20 First fluid guiding structure [0108] 21 Gap [0109] 22 Second end face [0110] 23 First width [0111] 24 Pressure line [0112] 25 First outer circumferential face [0113] 26 Second fluid guiding structure [0114] 27 Intake line [0115] 28 Second outer circumferential face [0116] 29 First rotation axis [0117] 30 Second rotation axis [0118] 31 Winding [0119] 32 Core [0120] 33 Magnet [0121] 34 Second width [0122] 35 Through-opening [0123] 36 Opening cross section [0124] 37 Connection means [0125] 38 Flow path [0126] 39 Circumferential direction